Giáo trình thực tập Ba Vì

All of Ba Vi mountainous plant communities belong to the formation class of evergreen tropical monsoon forests, of which evergreen trees dominate, and grow well under tropical monsoon climate on different soil types.

TOPIC 3: ECOLOGY AND BIODIVERSITY

3.1 PURPOSE, REQUIREMENTS AND METHODS OF FIELD STUDY

Field study aims to approach and apply proficiency the field research methods (observation skills, diary notes from the field, the survey data collection, analysis and synthesis of data in the field )

This is the most important targets, aiming to train the field skills for studentsfrom the very first day they contact with nature Students not only learn how toidentify the species in the field, the practice of recording observations, collecting data,but also exercise the analytical skills, the failure logic, truthfulness, accuracy andmeticulous as a basis for building scientific research style in the future

Fieldwork practice the studying skill and spirit of scientists, uplifting endured hardships, overcoming difficulties, behavioral agility, endurance, a spirit of cooperation and discipline in work

In nature, students and lecturers have to live in difficult conditions, lackingliving facilities, unstable weather and sometimes lose the pathway in the forests or inthe field so the real condition requires that students must have the spirit toendurance and overcome difficulties, agile, resourceful, and ready to overcome theobstacles in the natture This is an opportunity to evaluate disciplinary, seriousness,solidarity to help each other, teamwork skills as the basis for building thecharacteristic of scientists on field research of natural science and environment

Field study enhance the love for nature and biodiversity, sense for protection and sustainable development of the environment, raise awareness and passion for this job

in scientific research.

During the entire curriculum, this is the only course for field experience, so this

is a rare opportunity for students to contact with nature, through which students canobtain the knowledge that they have learned from nature, and on the other hand thiscourse increase love for the rich and beautiful nature of our country Loving natureand protecting the environment are undeniable acts of environmental scientists Ifstudents want to get it, they have to have the passion to learn, explore, analyzeobservations to understand the current status of environmental resources, nature andecological biodiversity in research areas Students should build a good understanding

about the task of learning, promote creativity, independent thinking in order to fulfillthe task of learning and raise awareness in scientific research.

3.1.2 Requirements and duties of students

+ Full and active participation for all time and line surveysin the field as well asanalyzing research specimens collected in the field

+ Observe, take note all the information collected directly in the field Write fielddiary everyday by following each survey day, survey path, survey point

+ Study actively secondary literature research, interview experts, surroundingcommunity and indigenous peoples as well as the systematical approach in integratedassessment

+ Be serious in study and research group work, promote creativity, spirit ofcooperation in groups

+ Write a scientific report summarizing and evaluating training course, emphasize theindependent research evaluation characteristics and recommend scientific ideas

3.1.3 Methods and scientific research skills students need to train and practice

+ Research method that study reference materials related to the field of study andresearch: the most basic method to understand comprehensively research issues thosescientists has been published This is considered as the official document with thehighest scientific value The following is the archived documents at the agency,organization, or local stations This kind of documents is for reference and they arevery good for navigating the research In this textbook, many research results havebeen used and there are many valuable data to help students understand the knowledgebefore and during field experience Each student should study this textbook beforegoing to the study area to have an overview about issues that they will study in thefinal report

+ Method in line survey and point survey (case studies):

Skill of surveying by group: it is always applied in the field study, in order to avoid

risks in the field and collect the information faster and more accurate, more objective.Study by group is considered as specific skills of environmental science, and throughthis method, students will form independent thinking in the process of debate ormaking scientific ideas, learn how to share information, build more accurate researchdirections, train presentation skills, persuasive ability, cooperation ability, the ability

to manage The number of groups will depend on the research topics and practicecontent

Skill of setting survey line and survey point: it is the core methods of field research In

the study the ecology and biodiversity this is seen as the success or failure of researchresults in scientific research Frequently, during the field survey, due to limited time,funds, and manpower so that scientists can not investigate the entire study area and it

is not necessary to investigate the entire study area because nature often has repeatedrule in its units, thus it is important to set the survey line and the survey point in thestudy area The survey line and the survey point should be the representatives of theentire ecological characteristics and biodiversity in the region Therefore survey linehave to go through all ecosystems, biomes in the region but need not to be repeated somany times in the same study area Those survey lines and survey points areconsidered as "key" to determine the biodiversity and ecological characteristicsthroughout the study area

Skills of taking note, observing and data collection: in this method students need to

apply skills of observing, recording and writing by pen or writing by the field researchtools such as cameras, recorder Observations are usually oriented towards speciescomposition, habitats that contain species composition, the obvious comparison to seethe law of their distribution throughout the habitats, then the conditions differencesbetween ecological habitats create the diversity of ecosystems, the vegetation in theecosystem These observations must be recorded immediately in the field diary.Records usually describe the biological characteristics of the organism, thedistribution rules, evaluations of their role in the environment, the ideas aboutphenomena or rules of study field Recorded data can be collected through fieldmeasurements and observation For example, the average number of individuals in 1

ha, invasive plants, forest cover density, average trunk diameter, preliminary volumeestimates of biomass Notes can also be a result of the community interviews, inscientific conference, the opinions of experts to create a basis for comments whenwriting scientific reports In the field experience time each student needs to havetake-note skill to accumulate field knowledge, gather primary information objectivelyand honestly as the basis to develop field research experience to work aftergraduation

+ Method of data processing: the data collected in any form will be processedimmediately in time of field experience or after finishing field experience The data istypically processed by different methods For the study of biodiversity and ecology,frequently the data is processed by statistical methods in Microsoft excel to know thenumber of species, species composition, the component structure of the system,universal life forms After statistical results are obtained, scientists often use this data

to construct graphs showing the relationship or correlation rules in fluctuations ofdiversity biology After that scientists can feel easy to evaluate or give ideas forscientific solution of study issues Besides, students can use other professionalsoftware (MapInfo, Biodiversity, ArcGIS ) to handle data in the form of maps (ingeographic information systems), the matrix method to evaluate the correlation ofaction and the level of impact

+ Building scientific reports: at the end of field experience course, each student mustsummarize the knowledge they have harvested, then process and write into a smallnewspaper or scientific journal called the final report Content of the report includesthe following parts:

Introduction of the necessity of research directions, research content (Forexample, analysis of differentiation of the diverse ecosystems of Ba Vi, analyzingdiverse aquatic species Dam Long - Ba Vi and sustainable development ), placeand time of the study, the purpose and requirements for the study, the concentratedarea and the range of content of research report, the introduction of research team andwhich reference is group works, which is individual works

Overview of study

List the scientific works, the documents that were published or archive (ifallowed) related to the content of research, and students have to evaluate theachievements, and limitations that need to study further to build the basis for theirreport content

Students have to provides an overview of the study area (the natural conditions,socio-economic related research subjects) to draw the necessary issues for theresearch

The study results

In this part, students should analyze and evaluate the data collected during the study.The scientific value is higher if the report analysis is more comprehensive, precise,and convincing This section dependent on objects, methods and limited researchissues, should be explored and guidelines carefully before implementing

Conclusions and recommendations

Review summary of the research findings in the form of a conclusion on each issue, aconclusion usually about 70 – 100 words State the recommendations based on theoutstanding issues in the conclusions

References

Must specify the references used to write scientific reports References are writtenaccording to the final thesis form of Hanoi University of Science, Vietnam NationalUniversity.

3.2 PLANT BIODIVERSITY

Plant Biodiversity Ba Vi is interesting object of study and systematic

Vietnam is one of the areas having the highest plant biodiver sity in the world.The formation of the high biodiversity is determined by numerous ecological factors,such as geography, geology, topography, climatology, hydrology, pedology, andnatural development history of biota Besides, the geographical location of Vietnamindicates the profound influences of the two highest biodiversity center in the globe,namely the Hymalaya and the Indonesia - Malaysia These are unique characteristics

of the biodiversity of Vietnam, reflected in a lot of data on the biodiversity of floraand plant communities (vegetations)

Located in the Vietnam biodiversity hotspot, Ba Vi not only represents thegeneral biodiversity of Vietnam, but also holds its own identity which is hardly found

in other areas in the country Many botanists therefore have concentrated on research,and then have published precious scientify data Some noticeable monographs are:

- Flore générale de l'Indo-chine (General Flora of the Indochina), edited by H.

Lecomte (1907-1931) and then supplemented by additional volumes until 1952

- Flore du Cambodge, du Laos et du Vietnam (Flora of Cambodia, Laos and

Vietnam), comprising 28 published volumes (1960-1996), edited by A.Aubréville

- An Illustrated Flora of Vietnam, consisting of three volumes, edited by Pham

Hoang Ho

- Analyse aire-géographique et écologique de la flore du Vietnam Nord, edited

by T Pocs, Acta Acad., 1965

- The vegetation of Ha Tay and basic characteristics of the flora of Ba Vi, by

Tran Van Thuy, Le Chan Tran, Huynh Nhung and others (1994)

- Other data surveyed and conducted by the authors of this book after manyyears of investigating and teaching on Ba Vi nature

These above monographs and other publications about the flora of Ba Vi havegiven us a quite complete overview of the biodiversity of Ba Vi, in terms of both floradiversity and vegetation diversity

- These species play a dominant role in almost plant communities of differentecosystems (except some waterbodies and the Artic)

- The study of vascular plants is much more comprehensive and detailed thanthat of algae and fungi phyla

In line with this concept, in the administrative boundary of Vietnam with anarea of around 33 million ha, it is recorded that the flora of Vietnam has about 11611species classified in six vascular plant phyla, including Rhyniophyta (Psilotophyta),Lycopodiophyta, Equisetophyta, Polypodiophyta, Pinophyta, and Magnoliophyta(Pham Hoang Ho, 2000)

It is estimated that in each about 3000 ha there is one plant species appearing, while in

an area of above 7300 ha of the Ba Vi National Park and its buffer zones, there are atleast 1121 species having been identified, belonging to four plyla of vascular plant(Lycopodiophyta, Polypodiophyta, Pinophyta, Magnoliophyta), average of about 7 haappeared a species The above number of species shows that Ba Vì is one of thecentres of plant species diversity in Vietnam in general and in Northern Vietnam inparticular

Table 1 Area and species number in some national parks and over Vietnam

National

Cat Tien

3.2.1.2 Characteristics of flora structure

The flora of Ba Vi is made up by 1121 vascular plant species, grouped in 586genera, 173 families, and 4 phyla as shown in Table 2.

Table 2 Taxa diversity of the flora of Ba Vi

Scientific name Vietnamese name Quantity Percentage (%) Quantity Percentage (%) Quantity Percentage (%)

Magnoliophyta, with the phylum Magnoliophyta always playing the absolute

dominant role in the flora structure Lycopodiophyta is always the phylum having the

smallest species richness, as well as on the lower status in the plant phylogenic tree

The species diversity of the phylum Polypodiophyta clearly displays its role in the

ecosystem of primary tropical forests that is less affected In comparison with its

counterparts of other florae in the region, the native representatives of phylum

Pinophyta are of great significance to the ecosystem; Ba Vi is one of a few sites in the

country which are diverse in conifer species, with a total of 20 species in 14 genera of

7 families Although many of them are planted ones, the natural gymnosperm species

of Ba Vi are well-known, playing an important role in forest structure, for example

Calocedrus macrolepsis Kurz, Podocarpus neriifolius D.Don… The correlation

between the percentages of families, genera and species number in different phyla is

displayed in Figure 1

To denote the level of diversity and stability of a flora, people usually take intoaccount the species-genus ratio (average species number of a genus), the genus-

family ratio (average number of genera per family), and the average number of species

in a family The flora of Ba Vi has the average species-genus ratio of 1.9 (1.91

species/1 genus), the average genus-family ratio of 3.38 (3.38 genus per family), and

the mean number of species per family is 6.47 Compared with their equivalents of

general Vietnam flora (which are 4.4 species-genus, 8.4 genus per family and 37.9

species per family respectively), these coefficients are much lower; this is in

accordance with the law of flora distribution and indicates that the flora of Ba Vi isone of components of the biodiversity of Vietnam flora.

Figure 1 The correlation between taxa diversity rates of phyla in Ba Vi flora

The flora of Ba Vi have the high ratio of the species number of classMagnoliopsida to those in the class Liliopsida, namely 5.4 times, while that ratio inthe flora of Vietnam is only 3.2, in the flora of Cuc Phuong is 3.8 Maybe the result ofsurveys on Liliopsida is not sufficient and demanding additional investigations;however, these coefficients seem to be in conformity with De Candolle’s statement(quoted by Le Tran Chan 1999): “the proportion of monocots decreases while goingfrom the Arctic to the equator” This corroborates the ecological nature of the tropicalflora of Ba Vi

Table 3 The ratio between the species number in class Magnoliopsida and in class

level of species diversity of the flora For florae that are less diverse in the frigidzones, the aggregate of species numbers of the 10 richest families alwayspredominates, constituting more than 70% of the total number, while in a diverse flora

in tropical zones, this rate never exceeds 50% Regarding Ba Vi’s flora, the ten richestfamilies include Asteraceae, Fabaeceae, Euphorbiaceae, Poaceae, Rubiaceae,Lauraceae, Moraceae, Rutaceae, Annonaceae and Fagaceae These ten families havethe total number of species being 411, accounting for 36.6% of the total species plantnumber of Ba Vi In comparison with that of the flora of Northern Vietnam, thisproportion differs There are 8 mutual families (Fabaeceae, Euphorbiaceae,Asteraceae, Poaceae, Rubiaceae, Lauraceae, Fagaceae, Moraceae), while Annonaceaeand Rutaceae do not repeat Respecting the ten above families in the flora of NorthernVietnam, their aggregrate species number make up about 39.2% of the total (PócsT.1965) This difference reflects the dissimilarity between two florae’s sizes;however, the data of both show that they are diverse tropical florae, as well asconstituent parts of the tropical forest ecosystems which are less impacted

3.2.1.3 The flora of Ba Vi is diverse in ecological adaptability, shown in life forms of its species

Ecological adaptability of plants is understood as the diversity in life forms inorder to adapt to the most adverse living conditions, to survive and repeat the lifecycle To assess the ecological nature of the flora, we have to classify and assess lifeforms of plant species and their life-form spectra The first one who set up theclassification of life forms was C Raunkiaerl; it is hence named Raunkiær's plant lifeforms Raunkiær's plant life forms were originally published in 1907 by the Danishplant ecologist Christen C Raunkiær It summarizes his insights into the way in whichthe location of the shoot apical meristem(s) that is (are) responsible for a plant'srenewal growth reflects the prevailing conditions under which the plant grows and towhich it is adapted In this diagram the plant parts that persist from year to year areshown in solid black, while those parts that typically fall off (leaves, flowers, fruits) ordie back (leafy shoots, inflorescences) are shown in outline

1 Phanerophytes - Shoot apical meristems are borne more than 25 cm

above the soil surface Examples of phaneropytes are thus all trees and a greatmany shrubs, including primarily tropical, arboreal monocots such as palms.Mechanically dependant species (see below) that remain rooted in the soil, such

as climbers, lianas, or vines, could be considered phanerophytes Arguably,however, mechanically dependant species that are not rooted at ground level,warrant a class of their own, i.e should be classified as epiphytes (see below)

2 Erect Chamaephytes - Shoot apical meristems are borne less than 25

cm above the soil, and produce erect shoots and (or) inflorescences

3 Prostrate Chamaephytes - Shoot apical meristems are borne less than

25 cm above the soil surface, and produce prostrate shoots and (or)inflorescences

4 Hemicryptophytes - Shoot apical meristems are borne at or near soil

level, as in biennial and perennial rosette plants, likeDaucus, Taraxacum, orVerbascum As indicated in the diagram, the above-ground portions of theseplants die back, after flowering and (or) during adverse climatic conditions

5 Cryptophytes - Geophyte with rhizome - Shoot apical meristems are

borne below the soil level, at the tip of a more or less elongate undergroundstem, or rhizome These apical meristems may grow monopodially and producelateral inflorescences that form the above-ground, photosynthetic portion of theplant (see note at left) Alternatively, the onset of flowering may cause therhizome to become erect and finish off in a photosynthetic inflorescence In thiscase a lateral branch continues the (sympodial) growth of the rhizome

6 Cryptophytes - Geophyte with bulb - Shoot apical meristems are borne

below the soil level, at the center or tip of a compact underground stem (corm orbulb, respectively, depending on whether the stem or the leaf bases becomeenlarged for storage of nutrients and water) Examples include Crocus andAllium, respectively

7 Cryptophytes - Helophytes - Much as in geophytes, shoot apical

meristems are borne below the soil level, but under water These apicalmeristems give rise both to indeterminate growth of the underwater shoot systemand to an emergent, determinate, aerial inflorescence

8 Attached Hydrophytes - The shoot system is entirely underwater.

Leaves are underwater, or float on the surface Only the inflorescence mayemerge above the water surface

9 Free-floating Hydrophytes - The entire plant may exist within the water

column, or on the surface of the water, with no connection to the bottom of thewater body Only the inflorescence may emerge above the water surface

10 (not shown) Epiphytes (incl Aerophytes) - These have also been

termed "mechanically dependent species," and as such differ from phanerophytes

in depending on other plants or on a more or less erect substrate, for theirsupport The entire plant may exist above ground, in some cases obtainingmoisture directly from the atmosphere (aerophytes, e.g Tillandsia)

11 (not shown) Therophytes - Shoot apical meristems persist during

unfavorable climatic conditions only within seeds Annuals and desertephemerals are examples of therophytes

Later the concept about life forms of C Raunkiaer has been applied forstudying florae and elaborated more as follows:

A Phanerophytes:

1 Megaphanerophytes: trees with height of beyond 25 metres

2 Mesophanerophytes: trees with height of between 8m – 25m

3 Microphanerophytes : shrub-form trees and shrubs with height 2m-8m

4 Nanophanerophytes : dwaft shrubs, woody grasses 25 cm – 2 m in height

5 Epiphytes: perennial plants that grows upon another plant or rock

6 Lianas: woody vines, liana

7 Herbaceous: plants that have no persistent woody stem above ground (life

forms of Bamboo)

B Chamaephytes

8 Chamaephytes: buds on persistent shoots near the ground – woody plants

with perennating buds borne close to the ground, no more than 25 cmabove the soil surface

11 Therophytes: Annual plants, which survive the unfavorable season in

the form of seeds

On the basis of data and specimens collected at Ba Vi, we identify the life form

of each species, and have statistical table of percentages of life forms in the flora of

Ba Vi, as follows:

Table 4 Proportions of species number in various life forms in Ba Vi flora

- The flora of Northern Vietnam and Ba Vi are both dominated byphanerophytes, which are the main component of the plant communities ofevergreen tropical dense forests and secondary tropical shrubs This is also themain biotope in the region, accounting for the largest area, most diverse

- The heterogeneity of groups of plants in remaining life-forms is dependent onthe divergence of natural conditions, area of florae and investigative level

- In both of the flora, one can see the dominance of phanerophytes (Ph) in thephylum Magnoliophyta, of which woody plants make up a significantproportion (except the class Liliopsida) They are also the most valued timberresource in the flora in respects of both quantity and economic value

3.2.1.4 Ba Vi flora converging diverse geographical distribution of the species

Under the theory of flora, each plant species has only one distribution area at aspecific time, not depending on the genetic origins and history of natural evolution.Species of flora that have the same area of distribution is called a geographicalelement, of which boundaries usually coincide with the distribution borders of thesespecies Research about distribution zones of plants denotes the relationships of thestudied flora with others and recognizes its features by means of the number ofendemic species and geographical element spectrum

As regard to biogeography, the flora of the Northwest Vietnam in general and

of Ba Vi in particular belongs to palaeotropics zone, Indian – Malaysian sub-zone,Indochinese region and Northern Vietnamese – South Chinese flora They have kind

of diverse relationships owing to the complex interactions from different flora; theserelationships are first expressed by theirs common species, which have the samedistribution area i.e the same geographical element, especially mutual endemic oneshaving narrow distribution area

For a integrated review of the relationship between Ba Vi flora with other flora,the analyses of their distribution area through geographical element spectra need to bedone Based on the species collected and analyzed, the geographical element spectra

of the flora of Ba Vi can be listed as follows:

Table 5 The geographical element spectrum of Ba Vì

Geographical element No of species Percentage (%)

I Endemic element

1 Tonkinese endemic element

2 Vietnamese endemic element

3 Indochinese endemic element

357

99 44 214

31,9

8,8 3,9 19,2

II Indian elements

4 Hymalayan element

5 Indian element

142

6 136

12,8

0,6 12,2

III Malesian elements

3,5

1,9 1,0 0,6

IV Asian subtropical elements

9 North Chinese element

10 Asian subtropical element

164

108 56

14,7

9,7 5,0

V Asian tropical elements

11 Hainanese-Taiwanese-Filipino element

12 Ansian continental tropical element

282

41 241

25,2

3,6 21,6

VI Other tropical elements

13 Palaeotropical elements

14 Circumtropical elements

49

25 24

4,4

2,2 2,2

VII Other elements

15 Widely disposing elements

16 Modern migrant and imported elements

84

32 52

7,5

2,9 4,6

of integrity in forest ecosystems remains high and requires attention to conservation

Regarding species of Vietnamese endemic species: They are ones sharing the

distribution area in the territory of Vietnam, consisting of 44 species (3.9%), showingthat the relationship between Ba Vi flora and the florae of Central and SouthernVietnam is not as obvious as its relationship with neighboring florae in NorthernVietnam in terms of origins

The relationship between Ba Vi plants and the florae of neighboring countries: First of all, these flora share Indochinese endemic species, i.e all species

having distribution zones in Vietnam, Laos, Cambodia, the tropical parts of Myanmar,Thailand (except the southernmost Malaysia or lower) They consist of 214 species,constituting 19.2% of the total species number, making the second largest group afterthat of Asian continental tropical element The abundance of species orginated fromIndochina demonstrates the diverse relationship of the flora in studied area with theflorae of Laos, Cambodia, Thailand and Myanmar The most noticeable evident is thatmany species found in these countries has the distribution zones covering the entirestudy area

The relationship between Indian florae and Ba Vi’s: It is clear and ample,

demonstated in the large number of mutual species (ranked 3rd in the geographicalelements), namely 136 species i.e 12.2% of total species numer They havedistribution zones stretching from India to Indochina (including the species distributed

in Indochina and also India) Perhaps the species richness of this element has beenformed by the penetration of species favoring hot, dry conditions, along the migration

of plants from the west

There are less plant species at Ba Vi sharing distribution zones with those

of Malesian flora: There are only 38 mutual species (about 3.5% of total species),

which are distributed in the study area and also islands of Malaysia and Indonesia, oreven Australia, i.e the florae in the south of Southeast Asia The low rate of thesespecies shows the looser relationship between Ba Vi flora and those florae in the farsouth

Ba Vi flora has similarities with the flora of Southern China This

characteristic is relevant to the principle of ecological geographical distribution of thespecies present in both florae (with quantity of 108 species, making up about 9.7%).The evidence proves that Ba Vi flora is more related to the flora of Southern Chinathan flora in the south The species from the north usually exist in colder, moisterplaces; hence in the study area, there is relative affluent individuals of the species inthat such geographical element Of more geographical distance is the flora ofsubtropics in South Asia or near Central Asia, which have dwindling relationshipsexpressed by the low percentage of the species having the same distribution zones (56species, about 5%)

The flora of Ba Vi has few relationship with flora of tropical islands: This

feature partly reflects the obstacles in the process of extending plant species’distribution, owing to the seperation by oceans It is shown in the small number ofspecies belonging to Hainanese - Taiwanese – Filipino element, namely 41 species

accounted for only 3.6% of the total species counted It was also similar to the nature

of Vietnam flora (2.6%)

In addition to those species which are evidences of the apparent relationshipsbetween the studied flora and other florae in the region, Ba Vi flora also hold aprofusion of species confirming its geographical nature These species are distributed

in Asian tropics (241 species, 21.6%) and palaeo-tropics (of Asia, Africa) Many ofthem belong to the endemic families and genera (Musaceae, Pandaceae ), whichdemonstrates the distinct characteristics of the flora of Indochina - the pelaeo-tropicalregion and the third greatest center of species diversity in the globe

3.2.2 Biodiversity of algae and cyanobacteria at Ba Vi

So far there’s been almost no systematic research about this issue at Ba Vi.Therefore, the synthesis of the field is based on seperate studies of fresh water bodieslike Dong Mo, Suoi Hai, Ba Che and publications about freshwater algae inNorthern Vietnam and their possibility to distribute in waterbodies circulating here

From the above data, at Ba Vi the most abundant presence of two algae phyla,namely Green algae (Chlorophyta) and Diatioms (Bacillariophyta), can be recorded,

in addition to the presence of cyanobacteria (Cyanobacteriophyta)

Initial surveys at some sites at Ba Vi show that Green algae are mainly species

in the genera Actinastrum, Pediastrum, Scenedesmus, Coelastrum belonging to the

class Protococcophyceae Classes Conjugatophyceae and Volvocophyceae have thesmall number and low density Diatoms (Bacillariophyta) are abundant with species in

the genera Surirella, Cytotella Cyanobacteria (Cyanobacteriophyta) is not many in

species and individual number, often appearing in paddy fields or small ponds Theanalytical results reveal that in waterbodies at low areas (Ao Sen, foot of Ba Che),species composition of Chlorophyta increase greatly in both density and speciesnumber, while in flowing bodies of water or ponds with relatively good quality, thedominant group is Diatoms (Bacillariophyta), especially in streams at the elevation ofabove 700m Pursuant to the species composition of algae communities, it can be saidthat the nutrient level of the area is relatively low, and the best water quality is ofmoutainous bodies of running water

3.2.3 Biodiversity and ecological characteristics of Ba Vi vegetation

3.2.3.1 Overview of natural conditions and human impacts – the ecological to form the Ba Vi vegetation.

Geographic location:

Ba Vi National Park is limited in latitudes 20o55' – 21o07' N and longitudes

105o18' – 105o30' E, located in 5 districts: Ba Vi, Thach That, Quoc Oai (Hanoi), andLuong Son, Ky Son (Hoa Binh) It is 60 km from Hanoi along Highway 21A, 87 Thenorth border is with the communes Ba Trai, Ba Vi, Tan Linh of Ba Vi district, Hanoi

The south border is with the communes Phuc Tien, Dan Hoa of Ky Son district, LamSon commune of Luong Son dictrict, Hoa Binh The east border is with the communesVan Hoa, Yen Bai (Ba Vi), Yen Quang (Luong Son), Yen Binh, Yen Trung, TienXuan (Thach That), Dong Xuan (Quoc Oai) In the west of the park, it also shareborder with the communes Khanh Thuong, Minh Quang of Ba Vi district, Hanoi, andPhu Minh of Ky Son district, Hoa Binh

Geology - Geomorphology:

+ Geological foundation of Ba Vi mountainous area has the following principalformations:

Lower subformation (Pl - TlVN): this subformation consists of sedimentary rocks

of volcanic origin, such as sandstones, dark gray, light green and reddish slates, grayshaly siltstones and sandstones These rocks are exposed from above ground to theelevation of 200-250m around the foot of Tan Vien and Hang Hum mounts at Ba Vi.Upper subformation (P2 T1VN2): This subformation is made up by the rocksincluding xpilit stone blocks and anbitofa, basalt, porfirit… These rocks aredistributed in a large area, including Tan Vien mountainous region which embraces

Ba Vi, Hang Hum moutainous, Ba Vi range at the elevation of 400m and 600m

Terrigenous sedimentary formation of Middle-Upper Triassic ages: thiscomprises sedimentary sandstones, sand-siltstones and claystones with various levels

of foliation, prevalent in the northern and eastern part of the area

Quaternary alluvial sediments: distributed in the plains of the north, along thebanks of Da and Red River

+The topography of Ba Vi is kind of varied with the major types of terrain asfollows:

Medium mountains of erosion and denudation with altitude 1000m-1300m: Includethe high peaks above 1000m and they belong to Ba Vi and Tan Vien Mountain Thehighest peak is Ba Vi with altitude of 1296m Most of the slopes on the steepmountain peaks, sometimes up to 450-500 are mainly slope erosion and slope gravity,only on the watershed of the mountain we could see where the terrain is flat shapecomfortable wide saddle However, the slopes remain weathering crust layer withdifferent thickness

Erosion and denudation mountains with altitude from 500 – 1000m: Include themounts at Tản Viên Năm region in surrounding area of Ba Vi, Tan Vien Mount Theside slope is often steep, around 25 - 350, on the location of the saddle-shaped seamsthe watershed is pretty flat

Erosion and denudation mountains with low altitude from 200m – 500m: include themounts at Tan Vien, Ba Vi, Hang Hum; and they are distributed in the West and theSouth of the region

Erosion and denudation hills with steep slope and altitude from 100 – 200m: Includethe hills surrounded Ba Vi mountain group Typical examples are Lang Thang hillwith altitude 178m, U Rồng hill with altitude 150m, Nam Voi with altitude nearly200m The hill sides often have slope about 8 - 150 or 15-200.

Erosion and denudation hills with altitude 80 – 100m: Include the low hills withdiscontinuous distribution or sometimes link together into rolling hills, wavy form,more distributed in the central, north and northeast of the Hill’s sides often havegradual slope from 8 - 140, sometimes it can be as great as 15 - 200

Hill delta and delta with altitude 10 – 30m:

The hill deltas distribute mostly in the north, and partly in the east There are lots ofmounds, hills rolling shape linked to a wavy surface

The deltas are alluvial areas along Da and Red River, with large area in the north andnortheast

Artificial lake with a depth of 10m: The small and medium-sized artificial lake formed

by the dam that stops the water flow in the valley of Ba Vi

Climate – Hydrology:

+ Climate

Although Ba Vi fits in the tropical monsoon climate with cold winter, but thedifference nature of the Ba Vi climate is shown clearly in compare with surroundingareas climate because rainfall increase with altitude, rainfall distribution and waterevaporation mode, temperature is more stable Thus, Ba Vi climate is considered asthe tropical monsoon climate, with cold winters, rainy summers, without dryingseasons, and it is typical climate for mountains Average annual temperature in thearea is 23.40 C In the low area, lowest temperature can go down to 2.70 C, highesttemperature can go up to 420C At altitude of 400m, average annual temperature is20.60 C From altitude of 1000m and above, average annual temperature is 160C only.Absolute lowest temperature can go down to 0.20C Absolute highest temperature is33.10 C Average annual rainfall is 2500 mm, distributed unevenly in the whole year,with highest precipitations in July, August Air humidity is 86.1% Lowland is usuallydry in December, January From elevation of 400m and above, there is no dry season

In winter there is North wind with a frequency > 40% In summer there is Southeastand Southwest winds with frequency of 25% This is a favorable ecological conditionsfor evergreen woody plants and evergreen forests by they form and develop

+Hydrology

River systems in the region are largely derived from the upstream mountainous Ba Viand Vien Nam areas The major streams and tributaries flow to the north, northeastand are tributaries of the Red River To the west of the region, the short and steep

streams than streams in the north and east, and they are tributaries of the Da River.These streams often cause flood in rainy season During the dry season the smallstreams are often exhausted The major streams in the area include: Cai, Mit, Ninh,Yen Cu, Bon

Da River flows at the south of Ba Vi mountain The river is wide with thick streamssystem such as Oi, Ca, Mit, Xoan wich usually supply water for production andliving of residents in buffer area Besides, there are artificial lakes such as Suoi Hai,Dong Mo, Hooc Cua and other water reservoirs, which not only have the function ofproviding water storage for tens of thousands of hectares of agricultural land anddomestic activities, but also create the space with beautiful landscape, serving theneeds for relaxing and sightseeing tourists Groundwater in the area is relativelyabundant, and in the eastern side there is more water than inwestern side because there

is more rainfall and the topography is less steep

Soil conditions:

The study area has feralit soils in hills and mountains are formed from different parentrocks, feralit soil on ancient alluvia, slopes converge soil and alluvial soil for rice.+ Red yellow feralit on Spilit rock: in Ba Vi mountain this soil is widespread.According to pedology study of Ba Vi National Park, in 1994, the soil in Ba Vi isgenerally not acidic, rich in odor and nitrogen; phosphorus, potassium levels ismedium Composition of the soil particles is less variable, mainly varying bythickness In general, the soil cover depth is greater than 50cm

+Red yellow feralit soil on sandstone, siltstone, claystone: these soils mainlydistribute on the hills with altitude of 200m and lower In areas which have forest,shrubs, there are high content of soil humus, nitrogen, phosphorus, potassium Incontrast, areas which do not have scrub, and have grassland only, there are lowcontent of humus, nitrogen, phosphorus, potassium There is also the brown basalt soildistributing in the region

+Brown gold feralit soil on ancient alluvial: this is common soil type on hill withaverage altitude of 30m Distributed as a continuous strip in high platform above thealluvial plains

+Slopes converge soil: this type of mixed soil between feralit soil on sandstone,siltstone, claystone and product of delluvi deposition of surface runoff This isartificial soil has been terraced for rice and vegetables

Alluvial soil for rice cultivation: This soil occupies a certain area in the study area.Mainly alluvial soil in the dike annual accretion is not, improved regularly foragriculture

Flora

The flora of Ba Vi mountain is relatively rich with representatives of 4 vascular plantsphyla They are Lycopodiophyta, Polypodiophyta, Pinophyta and Magnoliophyta.The flora of Ba Vi mountain includes 1121 species in 173 vascular plant families Thefamilies has many species is Fegaceae, Fabacea, Poaceace Because the climate ofthe region has relatively high humidity, so in altitude belt of 400 - 800m and above,there are a lot of ferns (including woody ferns) In addition, flora of Ba Vi has 133endemic species (including endemic and endemic North Vietnam) Obviously, thishigh rate of endemism reflects the unique nature of the flora of the.

Flora in Ba Vi area has not only the scientific value, but also economic benefits In

1121 species, there are 304 species that can use for medical, 183 species for wood,

100 species for humans and livestock’s food Among the trees that have greateconomic value in Ba Vi, we have to mention about planted pines Planted pine forest

in Da Chong provides not only the beautiful landscape for suburban areas of Hanoi,but it is also a significant source of pine resin and wood for construction Moreover in

Ba Vi, there are some other precious plants(though they do not have large volume) as:

De, doi

Forests in Ba Vi has a huge role in the protection and regulation of hydrology andprevent the risk of flooding - drought, reduce soil erosion, and forest vegetation canalso contribute to regulate the climate, purify the air

Currently in Ba Vi there are some new planted foret trees such as Eucalyptus, Acacia auriculiformis, Acacia mangium and some other trees.

From the above analysis, we can give important conclusion is: without the influence

of man, surely evergreen forests with broad-leaved trees dominate covered the entireregion, from the highest mountains to plains and slow drainage swamp

However, after a long-term exposure of repeated human activiteis, today evergreenforests only cover a few peaks in the Ba Vi (from altitude of 600m and above) Manyforests with rare genetic resource has permanently destroyed The area of remainingnatural forest is valuable of genetic resources for studying the relationship betweenvegetation and environment, so that we have to have some methods that exploit thearea reasonably and sustainably

Human impacts

Before influenced by human activities, the whole area of Ba Vi National Parkwas covered by various types of tropical evergreen forests, from the lowlands of thefoothills to the highest mountain of this huge mountains However, today, due to thestrong impacts from many aspects humna, a large portion of the park has no primaryforest cover, or even no forest cover, which was replaced by secondary or artificialcover Human population in this region is increasing rapidly In 2008 the population in

Ba Vi mountain is 89 928 people The Muong people is 65 %, Kinh people is 33%,

Dao people is 1%, Thai and Cao Lan people are 1% Agricultural production is theirtraditional economic activity, with the main crops are: Paddy rice, upland rice, corn ,cassava This characteristic leads to some difficulties as well as the ease in the forestconservation and development plans.

+Advantages: the education propaganda of the staffs is quite good, so people in thearea are aware of environment and forest protection Nowadays there is almost nooneburning the forest to cultivate Forest resources have been maintained and well-developed The labor force is abundant in the area, so they can participate incontracting, protection, regeneration, and plating new forests Some programs, such asgovernmental programs 327/CP, 661/CP, 134/CP, have initially improvedinfrastructure conditions, so that forestry jobs develop quite good, then people haveaccumulated much of experience in forest development and raised awareness of forestprotection

+Difficulty: in Ba Vi National Park, the population is mostly ethnic minorities, inwhich the Muong population is majority, accounting for 77.3% of the population inthe region, however, people in there still have low literacy levels, outdated farmingpractices, and people's lives depend primarily on agricultural production with lowincome and lack of investment for production

In summary, human activities in Ba Vi have close relationship and strongimpact to the natural ecosystem overthere Thus, we need to have proper economic -social solution, that can be used to address the relationship between man and nature,

to help people live in harmony with nature and to develop regional economy in thecontext of ecological environment sustainability

From the above analysis suggests that, the natural conditions and the humanimpact effects arising out of the natural vegetation abundance and diversity andplantations by the use of different directions This is an important basis for assessingthe biological diversity of vegetation

3.2.3.2 Feature of biodiversity of Ba Vi vegetation

The diversity of plant communities based on topography and elevation geography

The distribution of flora and fauna depends on topographical and ecologicalcharacteristics such as climate, soils on different altitudinal zones At Ba Vimountains, the differentiation of terrain and base temperature on the different altitudescreate varied forest types distributed at such elevations The vegetation here is richand diverse; although its ecological nature is of tropical vegetation, due to thelowering of the base temperature by elevation, the species structure has both typicalspecies of tropics and substropics The long-term research by scientists at Ba Vi

mountainous region gave a scientific basis for the classification of plant communitiesand animal populations by altitude as follows:

- On hilly terrain with elevation of below 250m, there is mainly secodaryhuman-impacted communities, which are natural forest having been wiped out,then replaced by dominating secondary shrub and grass communities Torestore the forest cover, from 1990 to present, Ba Vi National Park has actively

develop plantation of mainly Acacia mangium There are invertebrates often

appearing, for instance insects, earthworms, and vertebrate animals, such asmice, small birds, snakes

- On moutainous terrain, above the height of 300m, there are various elevationsappropriate for species of different ecological amplitudes:

- At elevations of 260 ÷ 400: Most of the area prior to 1990 were bare hills, but

after 1990, many of the hills have been greened with trees like Pinus spp., Acacia magnum, Acacia auriculiformis, Lagerstroemia speciosa, and the most recently, Cunninghamia konishii which is transposed from Sa Pa The common

animals here are insects, earthworms, leeches, small mammals, birds andreptiles Besides, there are some areas of natural regeneration of forestswhich are ecologically meaningful to the environment

- From 400 to 600m in elevation is the naturally regenerated forests on

post-agricultural lands, with dominant plant species là Liquidamba formosana Hance, Macaranga denticulata (Blume) Muell – Argent, Mallotus apelta Muell - Argent, Trema orientalis (L.) Blume… In this layer, it is estimated that

there are 23 ÷ 27 animal species

- Altitudinal from 600 m to 800 m is the transitional belt between the typicaltropical forest ecosystem and the tropical forests on sub-moutains with sub-tropical temperature In addition to the common form which is secondary forestwith species composition similar to the above communities, there are someless-impacted forest remnants, specifically found in the remaining area of oldFrench-built villas around the elevation of 700m The canopy storey is mainlyspecies of the families as Meliaceae, Lauraceae, Sapindaceae, Fagaceae,Fabaceae This is the most diverse communities, having scientific values andneeding conservation focus

- At the elevation of 800 meters, in the area of the church, one may find

Podocarpus neriifolius D.Don, with diameter of 30cm, and many organisms of the genus Michelia spp and the species Toona sureni (Blume) Merr with trunk

diameter of 50cm The forests at this elevation is tropical forests on moutains, where the temperature is lower, hence the number of commonspecies is smaller, but there are species with great scientific and economic

sub-values, such as macaque, black bear, Sumatran serow, flying squirrel In therange of this elevation, forests are still abundant developing on steep slopes,less affected by humans so having the most ample composition of mammalsand birds at Ba Vi.

- At elevations of between 800m and 1200m: primary vegetation with big trees,higher than 25m However, this forest also has traces of human influences Thisprevalent forest type is evergreen broad-leaved forest, somewhere growingmixed with conifers This forest type illustrates the forming process of thetypical vegetation appearing in Northwest Vietnam, and the type in accordancewith the common forest types in Yunnan and Guizhou, or even more, inHimalaya

- At the elevation of 900m, there are some typical tree species growing in the

west of Tan Vien slopes as Calocedrus macrolepsis Kurz; and in the areas

around the ridge, there are communities dominated by species of the genera

Quercus, Cinnamomum, Michelia, mixed with Calocedrus macrolepsis Kurz at

some places In particular, on the crest of Tan Vien mount, due to the foggy,humid, windy climatic conditions and thin soil cover on basal conglomerates,

we can only see Calocedrus macrolepsis Kurz, some species of the genus Rhododendron, and dwarf grassland absolutely dominated by Arundinaria baviensis Balansa At altitudes of above 1200m, moss forests can be found At

the highest peak (King Peak, 1201m high), moss forest occupies a large areaand also a smaller area at Tan Vien The cloud forest thrives on bright yellowporphyric soils and oxisols, favorable for the growth of moss and lichen Thisforest type - poplular in the "fog belt" – is a very beautiful forest and alsoknown as "fairy forest" The diversity of animals is inversely proportional toaltitudes, as where there are high elevations, steep slopes, or extreme climaticconditions (too hot, too cold, too wet, too dry ), for instance the peaks of Ba

Vi National Park, animal species are hardly seen

Biodiversity of the vegetation by morphological – ecological structure

In view of UNESCO (1973), the units of vegetation are distinguished primarily

by morphological structure that is based on the biological characteristics ofcommunities, such as major life forms (trees, shrubs, grass ), canopy cover density(dense, sparse, open ), seasonal leaf phenotypes (evergreen, deciduous ), andecological features (at altitudinal zones, on different soil types, on the non-zonal soils,

on wetlands ) Based on these criteria, Ba Vi National Park there are two main types

of vegetation: Natural and human-impacted vegetations, which are identified andclassified by the following principles:

a Natural vegetation:

In principle, the method to determine and classify natural vegetations are made

by applying the framework of UNESCO's classification (1973), the scientific basis ofthe FAO classification system (1989) applied to tropical Asian countries

Pursuant to this method, the driving ecological factors of vegetations andgeographical distribution rules are defined as habitats in which all levels of theclassification of UNESCO are sorted

All units of climax vegetation, in the steadiest state in the environment, or asprimary ones prior to human impacts are placed in chief positions The secondaryunits deriving from climax states are arranged by natural ecological succession series.With this classification, the driving ecological factors will comprise entirely, even thesmallest level in classification hierachy – which involves species structure,morphology and composition This is "the classification which all botanists consent."(Thai Van Trung 1978)

Divergence of parent rocks, soils and submergence modes (to supply water forplant growth) are all contributing to vegetation classification The main criteria arespecies composition and biological characteristics of communities

The distribution of vegetation by elevation, is determined by the principles ofUNESCO, using indicators of regional climates These indicators are kind of in linewith the differentiation of species structure – composition of climax communities (theleast disturbed forest) The indicatorss based on temperature - humidity aresummarized in the publication of Pham Ngoc Toan, Phan Tat Dac (1993), NguyenKhanh Van et al (2000) and the data measured at local stations The altitudinalboundary of each belt is corrected in accordance with transition zones of vegetationdifferentiation by elevation (0m - 700m and 700m - 1600m) On this basis, it is likely

to recognize that all the natural plant communities belong to a group primaryformation of evergreen tropical monsoon dense forests The group formation is made

up mainly by trees with height of above 6m (± 1m), having closed canopies, which areoverlapped with each other (in vertical projection) to create a continuous screenblocking most sunlight The canopy layer never defoliate utterly The deciduousindividuals can penetrate, but never exceed 25% of total trees (Thai Van Trung, 1978;Schmid M., 1974) Every tree has buds for protection against dry, cold season orboth This formation still survive in the humid or rainny tropical monsoon climate

From this above group formation, it has diverged into four primary formationsdepending on the differences in prominent ecological conditions of soils or altitudinalclimatic zones Those four ones are:

1 Formation of plants on alluvial riparian zones and draining, slowlyconverging, sloping areas at foothills

2 Formation of aquatic plants

3 Formation of plants on draining lowland with elevation of below 700m

4 Formation of plants on low mountains with elevation of 70m - 1600m

These formation are continually divided into 5 sub-formations and 20 differentcommunities (listed below)

b Human-impacted vegetation

The driving ecological factor is human ecology The species structure,morphology, composition is determined entirely by farming practices, as well aslevels and methods of cultivation The formation of artificial communities do not rely

on whether they are adaptive to the natural environment or not, but depending onconditions prescribed by humans through forms of different farming methods andmaintaining regularly such methods Regarding the classification based on growthcycles of plants (perennial, annual or short-term), in the Ba Vi there are 10 human-impacted communities identified

BIODIVERSITY OF PLANT COMMUNITIES OF BA VI

NATURAL VEGETATION

1 Formation class of evergreen monsoon tropical forests

All of Ba Vi mountainous plant communities belong to the formation class ofevergreen tropical monsoon forests, of which evergreen trees dominate, and grow wellunder tropical monsoon climate on different soil types

1.a Formation of evergreen monsoon tropical dense forests on alluvial soils

This formation distributes on alluvial plains and riparian zones, which are silted

up or not, and have characteristics as described in Section 1 of the Classification ofVegetation

1.a(1) Sub-formation of evergreen monsoon tropical dense forests on alluvial riparian zones and draining, slowly converging, sloping areas

In the sub-formation, the whole of primitive communities has been devastated sothey no longer exist The secondary communities develop on base of primitive onesare:

1 Grass communities mid-height, secondary, dominated by Chysopogon aciculatus (Retz.) Trin., Cynodon dactylon L sometimes mixed with other grasses on

frequent grazing

These communities grow on natural pastures that are frequently trampled by

livestock The dominant species are Chysopogon aciculatus and Cynodon dactylon, but occasionally they grow mixed with other grass species, such as Imperata cylindrica (L.) P Beauv., and Digitaria violasens Link These communities live on

waste land which is not cultivated, sometimes having areas of homogeneous

populations of the dominant Chysopogon aciculatus and Cynodon dactylon.

1.b Formation of evergreen tropical monsoon broadleaf dense forests on swamps

This formation currently has only secondary communities scattered in theresearch area

1.b(1) Sub-formation of evergreen tropical monsoon broadleaf dense forests on swamps and its secondary communities

Primary communities have disappeared, replaced by secondary ones, which can

be met at low-lying areas and have supply of fresh water regularly or almostthroughout the year

2 Grass communities dominated by Phragmites vallatoria (L.) Veldk.

Distributed in the freshwater of Ba Vi area, from the water body of rivers and

streams to lakes, ponds and swamps in the area The dominant species is Phragmites vallatoria (L.) Veldk Other species growing together may be Panicum repens L., Ischaemum sp, Isachne sp… to form the grasslands These communities are kind ofpopular in the area, possible to be seen around streams, Dam Long, Ao Vua,waterbodies around Hoc Cua, lakes at Ba Che area…; they are indicators for waterquality and helpful in improving polluted water

3 Submerged and floating aquatic communities

The dominant species are Nelumbo nucifera Gaertn., Nymphaea sp, Hydrilla verticillata (L.f.) Royle, growing submerged and erect in the water Examples of floating species are Lemna minor L., Pistia stratioides L., and Azolla pinata R Br.

Like the above ones, these comnunities are distributed in and on waterbodies in thearea, such as ones at Dam Long, Ao Vua, Hoc Cua, Ba Che… It is worth noticing that

the community of Eichhornia crassipes (Mares) Solms - a highly competitive invasive

species - has been developing in almost waterbodies, along with other species which

have high ability to survive like Pistia stratioides L It should be noted monitoring and

management communities to ecosystem stability in region

1.c Formation of evergreen tropical monsoon broadleaf dense forests on draining lowland (below 700m)

Basic characteristics of this formation is developing under a hot, humid tropicalmonsoon climate, on various soil types ranging from old alluvial soils to zonal soilsthat develop on different types of parent rocks

1.c(1) Sub-formation of evergreen tropical monsoon broadleaf dense forests

on old alluvial soils and its secondary communities

Prior to human impacts, these primary communities were likely to cover entirebanks of Da River They grew on old alluvial soils, which are relatively thick, notsilted up, and having poor water retention.

4 Secondary shrub communities dominated by Melastoma septemervium (Lour.)

Merr. , Breynia fruticosa (L.) Hook.f , Mimosa pudica L

These species of low scrublands with average height below 0.5 meters Common

species include Melastoma septemervium (Lour.) Merr., Breynia fruticosa (L.) Hook.f., especially dominating on wastelands which are barren, rocky or aggressively eroded At some points, Mimosa pudica L appears and grows scattered or mixed with these above dominant species These communities occupy small, scattered areas

5 Low grass communities dominated by Chysopogon aciculatus (Retz.) Trin., Cynodon dactylon L ,

These are similar to the communities growing on alluvial soils, due to thephenomenon of convergence along stages of ecological succession Besides thesedominant species, sometimes there are other plants growing mixed, such as some

species of Digitaria and some species of Asteraceae family

1.c(2) Sub-formation of evergreen tropical monsoon with broadleaf plants

on ferelit soil, well-drained, weathered from various parent rocks and the secondary communities

This sub-formation distribute throughout hills, as well as lower parts of Ba Vimount, Hang Hum mount, and anonymous mounts in the Ba Vi mountain range Theygrow mainly on yellow-brown oxisols, which has been formed on alkalic extrusiveigneous rocks, having moderate thickness and average fertility They are under themountainous tropical monsoon climate, with the annual mean temperature being 200C,indicating warm weathers The annual average rainfall reaches 2000-2350m Beforeimpacted by human activities, communities of evergreen tropical monsoon broadleaf

forests had developed fully under the particular climate and on the soils formed by

this climate type, covering the entire research area Over long time, due to repetitivehuman impacts, these communities now occupy areas which are not large, andscattered on those mountains The current forest communities are mainly secondaryones, getting more and more impacted, deforested, and replaced by secondary shrub,grass and cultivated plant communities There are only a few remaining communitieswhich are less impacted scattered around elevation of 600 m in the old French resort

6 Less impacted communities of evergreen tropical monsoon dense forest These are the most unique and the most characteristic communities in theformation They have the structure typical for tropical communities, comprising threetree layers, one shrub and one herb layer The emergent layer is made up by big treeswith height above 30 m, small quantity, distributing sparse and unclear at some points

The diameter of trunk ranges between 70cm - 110cm; the canopy diameter varied ondifferent species, ranging between 7m and 14m The average density is 30 trees/ha.

The species identified include Amoora gigantea Pierre, Caryodaphnosis baviensis (Lecomte) Airy Shaw, Dracontomelum duperrealum Pierre, Madhuca pasquieri (Dub.) H.J.Lam., Ficus spp… A lot of trees have relatively large diameter but not

sufficient height, making their form look unhealthily twisted The presence of this treefloor indicates a long-term stability of communities under fixed natural conditions ofthe region

The ecological dominant storey distribute fairly evenly and continuously in thestudy area, with the height of approximately 25m, average trunk diameter of around35cm – 60cm, canopy cover being 50%, and relatively high density (about 200 - 300

trees/ha) The dominant species identified in the area are Caryodaphnosis baviensis (Lecomte) Airy Shaw (very popular), Michelia balansae (A.DC.) Dandy, Pometia pinata J.R et G Forst (popular), Toona sp, Litsea baviensis Hayata (popular), Michelia sp, Cryptocarya lenticellata Lecomte, Re Cinnamomum sp, Endospermum chinense Benth., Dracontomelum duperrealum Pierre, Madhuca pasquieri (Dub.) H.J.Lam (popular), Lithocarpus corneus (Lour.) Rebder (very popular), Elaeocarpus balansae A DC., Ficus spp, Peltophorum dasyrrachis var tonkinensis (Pierre) K et S.S Larsen, Canarium album (Lour.) Raeush ex DC

The understory tree is somewhat thick, continuous, having canopy cover beyond40%, relatively high density of 300-400 trees/ha, average height of 10m - 17m,average trunk diameter of 25cm, average canopy diameter of 6m Some examples of

the dominant species are Actinodaphne obovata Blume, Bischofia javanica Blume, Michelia sp, Neonauclea purpurea (Roxb.) Merr (in wet habitat), Cephalanthus angustifolius Lour., Elaeocarpus hainanensis Oliv Hydnocarpus hainamensis (Merr.) Sleurner, Hydnocarpus kurzii (King) Warb., Syzygium spp , Archidendron sp, Sauraunia sp, Garcinia spp, Wrightia lecomtei Pit, Pterospermum heterophyllum Hance, Croton tiglium L, Knema confera Warb., Schefflera octophylla (Lour.) Harms, Saraca dives Pierre (in wet habitat).

The shrub storey is quite sparse, mainly made up by regenerating tree species ofthe upper layers and other plant species With the average height ranging between 2-

5m, the common dominant species in this layer are classified into the genera Cyathea, Schefflera, Cinnamomum, Diospyros, Garcinia, Lithocarpus, Ficus, Evodia, Archidendron, Ardisia, Wendlandia, Sterculia, and other regenerating trees Their

density is about 3000 individuals per ha

The herb layer is rich in species diversity but sparse in individual density Fernplants consist of mainly representatives of the families Selaginellaceae,Angiopteridaceae, Schizeaceae, Gleicheniaceae, Polypodiaceae, Pteridaceae, and

Adiantaceae Seed plant species are representatives of some genera, for instance

Arenga, Calamus, Daemonorops, Amorphophalus, Phrynium, Musa, Amomum, Costus, Begonia,

The intermediate layer includes vine species belonging to the families Fabaceae,Asclepiadaceae, Cucurbitaceae, Vitaceae, Dioscoreaceae, and Smilacaceae,

Ephytes are abundant, primarily made up by organisms of the familiesAspleniaceae, Loranthaceae, Orchidaceae…

Overall, this are the most diverse and abundant communities in the area, as well

as the most difficult ones to study and analyze Mainly distributed in the boundary of

Ba Vi National Park, around elevation 600m - 700m The values of biodiversity ofthese communities also lie in that they have numerous species having scientific andeconomic worth, and many rare and endemic ones that are hardly found in other areas

7 Secondary, evergreen tropical broadleaf dense forest communities

They are derived from the least disturbed forest types above, through thedestruction or overexploitation or shifting cultivation and fallow This communityremains around altitude 400m - 700m, primary structure has been broken before, both

in terms of forest canopy structure and species composition The species of primarycommunity almost absent only species characterized by high light and droughttolerant These communities are dominated by the species Liquidamba formosana Hance, Macaranga denticulata (Blume) Muell - Argent, with a simple community

structure, consisting of only one tree layer, being 12m - 15m in height, 70% in canopy

cover and 500 trees - 800 trees / ha in community density Liquidamba formosana

Hance is the species which had been chosen to be the natural regenerating one, so itbecomes the most dominant tree species in the communities Subsidiary regenerating

species is Macaranga denticulata (Blume) Muell – Argent, growing under the canopy

of L formosna Other identified species are Mallotus apelta Muell - Argent, Phyllanthus reticulatus Poir.

On moist areas where secondary forests develop well, it is likely to find

Ormosia balansae Drake, Wrightia lecomtei Pit., and some other species scattered such as Ficus nervosa Heyne ex Roth, Ficus vasculosa Wall ex Miq., Dillenia hookeri Pierre.

In the tree storey, average trunk diameter is 15 cm, average height is about 13m.Density of trees (having trunk diameter of 10 cm - 30 cm and height of 7 m - 16 m)are estimated to be 650 trees / ha The species composition is simple, mainlycomposed of those species identified above These communities can be considered assecondary ones which have recovered relatively well in terms of spatial structure,biological properties and ecological adaptation Regarding species composition, they

are in the first stage of the secondary succession, and will have replacement in speciescomposition in the future in accordance with the inherent one.

They are also strongly affected, so ephytes are usually rare, and sometimesabsent The scrub and grass layer grows thicker with complicated compositions,mainly comprising species of the families Euphorbiaceae, Rubiaceae, Polypodiaceae,Melastomaceae, and Asteraceae - mostly invasive species This communities is lowtree density, some places is only about 40% - 60%, specially on the moist side wheretrees have been cut down sharply, appearance of bamboo species and they developstrongly, however, the size of is not large development form large forests ofbamboo.Though, it should be considered as the recession succession series obstacle tothe recovery and regeneration of forests

8 Secondary evergreen broadleaf shrub communities

These communities are scattered throughout hills and low mountains, includingthe foot of Tan Vien Mountain, Ba Vi Mountain, Hang Hum Mountain and severalother mountains The component species are mainly shrub plants, with height of from2m-5m, evergreen and broadleaf The shrubs are originally trees in the composition ofprimary communities, which have been devastated and now are regenerating alongwith other invasive species The canopy cover is 70% (including intermediate or

understory laters) Common species are Macaranga denticulata (Blume) Muell Argent, Mallotus apelta Muell - Argent, Phyllanthus reticulatus Poir; invasive species are Rhodomyrtus tomentosa (Aiton) Hassk., Melastoma septemervium (Lour.)

-Merr These shrub communities are very advantegeous to the natural regeneration offorests

9 Secondary average-height savanna communities

These include mainly rice-formed grass species, with average height of 0.5 m - 2

m, distributed on an area which had been cleared, farmed then left fallow throughout

low hills The dominant grasses are Imperata cylindrica L., Saccharum spontaneum L , sometimes we can see Miscanthus sinensis Andres, Neyraudia reynaudiana (Kunth)

Keng ex Hitchc Instrusive plants are few or not existing; the canopy cover of shrub isless than 10%

1.d Formation of evergreen tropical monsoon dense forests on mountains (700m - 1300m high is the limit of the highest peak), draining soil

sub-The formation develops on low mountains, on feralit soil formed by weatheringdifferent parent rocks, under the tropical monsoon climate with the lowering oftemperature due to elevation Owing to the development under the wet and relativelycool condition and enduring rainy periods, the formation is chiefly dominated byevergreen woody plants, fairly large in size, making up the storeys quite clearly inevergreen forests However, due to living in the cold climate of winter annually, the

trees are evergreen, but all enveloped by bud scales and having a significant winteringperiod The trunk is enveloped by thick and rough bark; many trees have bạnh vè.This formation has only one sub-formation.

1.d (1) Sub-formation of evergreen tropical monsoon forests on low mountains, soils formed from different parent rocks, and secondary communities

The elevation changes lead to change some features of climate, especiallymoisture regime and temperature rise caused formation, species composition, canopystructure is very clear changes, the forest usually have 4 storey including 2 storeytimber, on the peak and the watershed of mountains the forest storey sometimes only1-2 which has a wood storey, low height, pillow-shaped canopy, adapt to the intensity

of the wind Differences in topography lead to differences in microclimate, drainageregime and soil properties The features of the sub-formation as well as the formationare controlled within the boundaries of types of ferelit soil, weathered from differentparent rocks such as shale, sandstone All of these soil types are distributed onslopes, peak lines and surfaces, characterized by good drainage Above 1000m, due tolowering the temperature, the weathering process is affected, and microbial activity inthe decomposition process is not strong, leading to forming thick humus layer Thischaracteristic of the soil is also one of the factors differentiating the plant communitieswithin the same climatic belt

In this sub-formation, there are some following communities:

10 Broadleaf evergreen dense forest communities, less affected, developing onsteep slopes where the soil layer is still humid and thick

This forest type is considered vegetation close relationship with the formationNorth of Vietnam - South of China is forest developed from Yunnan - Guizhou toNorth of Vietnam This is evidenced by the structure of forest communities on thewestern slopes of Tan Vien peaks altitude around 900m The structure is quite

different communities including mixed broadleaf trees and conifers as Calocedrus macrolepis Kurz, Quercus platycalyx Hicket et A Camus, Manglietia fordiana (Hemsl.) Oliv., Lithocarpus sp, Michelia sp Also see this forest around peak Ngoc

Hoa The areas of slopes between the elevation of 900m and around 1000m all belong

to these communities, at altitude 900m or less can be seen different characteristics ofcommunity tropical evergreen forests of this elevation primarily because the structurestoreys and species composition The forests have a four-story structure, including twotree layers, storey rise above canopy trees that are not present, like other forestcommunities in other areas of the same high belt The trees are evergreen species, andmost of them are broadleaf trees; conifers can appear but cannot dominate and oftengrow mixed with broadleaf trees

In the ecological dominant layer, the identified dominant species include

broadleaf species such as Castanopsis hystrix DC in Seem , Castanopsis fissoides Chun et P.H.Ho Castanopsis tonkinensis Seem., Quercus platycalyx Hicket et A Camus, Manglietia fordiana (Hemsl.) Oliv., Lithocarpus sp, Michelia sp, besides the scattered appearance of coniferous species, for instance Podocarpus imbricatus (Blume) de Laub, and Calocedrus macrolepis Kurz The representatives of this tree

layer have heights of between 22m-25m, and the average trunk diameter of 100cm

70cm-The understory of tree mostly comprises of broadleaf evergreen trees: strongly

regenerating species of the Fagaceae and other species like Sauraunia sp, Cryptocarya lenticellata Lecomte, Re Cinnamomum sp, Wrightia sp, Michelia sp, Manglietia fordiana (Hemsl.) Oliv In these above layers, vines and epiphytes grow

fewer than those in the forest communities in high and low belt

The scrub storey is mainly made up by regenerating trees of the upper layers,with density of about 3000 individuals / ha In some points there is appearance of

other species of the genera Ficus, Schefflera, Litsea

The herb layer is less developed, primarily including individuals of the genera

Amomum, Begonia, Impatien, Pteris…

Like the less effected forest communities in low belt, these are the communitieshaving high biodiversity and conservation values, requiring conservation anddevelopment solutions

11 Broadleaf evergreen forest communities less affected, growing on peak linesand surfaces of peak

As a subtype of pedology from monsoon tropical evergreen dense forest on sub-,mountains typically developed in strong wind conditions, rapid drainage regime ontop Besides this place is influenced by moist regimes often clouds so facilitate thesmall trees scattered pillow, under strong wind development and lichens and mossesthrive So it is also called mossy forest or wonderland forest This forest type ismainly distributed on the King top with large area at altitude 1201m and a smallerarea at Tản Viên peak Forests usually have 2 stories , wood storey with big trees

growing from the slopes as the above communities (10) as Castanopsis hystrix DC in Seem Castanopsis fissoides Chun et P.H.Ho Castanopsis tonkinensis Seem Quercus platycalyx Hicket et A Camus, Manglietia fordiana (Hemsl.) Oliv., Lithocarpus sp, Michelia sp On the peak lines and peak surfaces, there are low-height tree communities appearing, dominated by Rhododendron simsii Planch., Enkianthus quinqueflorus Lour In areas around peaks where have thicker soil layers, it is possible to find other species such as Quercus platycalyx Hicket et A Camus, Quercus sp, Quercus bambusaefolia Hance in Seem, Calocedrus macrolepis Kurz.,

Pơmu Fokienia hodginsii (Dunn) A Henry et Thomas… These species are larger in

size, about 15 meters in average height, 40 cm in the average trunk diameter, and 70%

in canopy cover Some times species of gymnosperms as Calocedrus macrolepis

Kurz dominate in areas of about 1 - 3 ha around the peaks above 1000m

Especially on the top and the watershed, where thin soil layers often appear

grasslands height medium absolute superiority belongs to a species Arundinaria baviensis Balansa Epiphytes species of families as Loranthaceae, Orchidaceae, và

Asplendiaceae are abundant and epiphytes growing on trees and rocks Densityregenerated plants quite high equivalent to the above communities (10) about 3000trees/ha

This community is one of the rarest communities of Ba Vi national park, needing

to be focused on conservation and development

VEGETATION FORMED BY HUMAN

12 Planted community Acacia auriculaeformis Cunnell ex Benth

These communities occupy a relatively large area, mainly distributed in the lowhills and low mountains below 500m of Ba Vi Planted forest communities of the

species Acacia auriculiformis develop well, with height of from 5-15m and relatively

closed, continuous canopy The reason for the fine development of plantationcommunities is attributed to the influence of climate and soil The soils are oxysols,formed by weathering alkalic extrusive igneous rocks, having thick layers (more than50cm) and average fertility The mean temperature is 20 - 220C; the average annualrainfall is about 2000 mm The summer is hot and cool, while the winters has coldmonths

13 Planted communities Acacia magnum Willd.

Occupying a relatively large area, these communities are distributed sparsely at

foots of Ba Vi mountain or hills taller than 30 - 200m (hill Conma) Acacia mangium could develop to reach the height of 5-10m Acacia mangium is grown on feralit soil

and on shelves III where soil layer is thick and relatively humid It grows under themean temperature of 22 – 230C, annual rainfall of 1720 – 2000mm The summerclimate is hot, and the winters has cold months

14 Planted communities Eucalyptus spp,

These communities are distributed mainly on low hills or near large lakes: LakeStream, Lake Marble Son and the foot of Ba Vi Mountain Capable of reaching 10-

12m in height, the Eucalyptus spp communities has simple structure with only one

tree layer and grasses grow sparse Climate of low belt (10-200m) has the meantemperature of 22 - 230C, the annual rainfall of 1720 - 2000 mm, hot summer and coldmonths in winter

15 Planted communities Pinus merkusiana Cool et Gaussen

These communities were planted on remaining hills and mountains of Ba Traiand low areas of Ba Vi around the elevation of 400m The forest have only one treeyear Usually grown on degraded, strongly eroded, pine forests develop under the hotclimate with annual mean temperature of 22-230C, annual rainfall of 1720 - 2000 mm.

16 Planted communities Cunninghamia konishii Hayata

These communities occupy a small area, mainly distributed on hills andmountains left, as well as feet of mountains at the elevation of 30 - 200 meters Theplantations are in the testing phase Planting density is about 4m/trees, the average

height is about 7m; and the canopy is going to close Cunninghamia konishii Hayata

planted at low belt is unable to thrive due to incompatibility with climatic conditions,

as well as the competition of tropical plants which have higher vitality like Saraca spp., Schefflera octophylla (Lour.) Harms, Macaranga denticulata (Blume) Muell- Arg., Mallotus barbatus (Wall.) Muell , making it difficult to be able to reach the

maximum size

17 Association of Oryza sativa L.

The association are grown in form of intensive farming, mainly distributed indrainage basin in the region, on alluvial soils having renovated and proactiveirrigation The majority of crop acreage has two rice crops per year On areas that donot have initiative in irrigation, rice is intercropped with vegetable crops in the drier

season There are many varieties of Oryza sativa L used as main crops, since their

productivity and quality is dependent heavily cultivation mode, especially irrigationsystem

18 Communities of annual upland crops

These communities are cultivated on alluvial soils silted annually and alluvialsoils which do not have initiative in irrigation in the entire farming time of a year The

main crops include corn Zea mays L., sweet potato Ipomoea batatas (L.) Poir in Lamk., potato Solanum tuberosum L., cassave Manihot esculenta Crantz, and other

short-term vegetable and cash crops The primary products are purposed forconsumption locally; the acreage is settled and inable to be explanded, hence theattention should be paid to forms of cultivation and crops rather than increasingfarming scale and area

19 Shifting cultivation:

Existing because of former farming practice, the slash-and-burn cultivation isdiminishing and tending to be replaced On swiddens (temporary or regular), peopleusually grow rice and vegetables In some areas, grazing grasses are planted, for

example Pennisetum purpureum Schum., Panicum maximum Jacq

20 Planted communities around settlements:

Distributed along settlements and clearly differentiated by distribution

characteristics of each one The planted species are Melia azedarach L., Citrus sinensis (L.) Osb., Citrus aurantifolia (Christm & Panzer) Swingle, Dimocarpus longan Lour.; Carica papaya L.; Musa paradisiaca L.… and others On the highland tourist area, the effective crop is chayote Sechium edule (Jacq.) Swartz , potential to

be researched to be grown at large scale in the ecological sustainable economic model,

in order to serve tourist and urban needs

21 Concentrated area of perennial plant: Tea Camellia sinensis (L.) Kuntze

There are only small areas scattered in the buffer zone of the national park.Although it is a valuable cash crops, but currently the processing technologies here arepoor and the production is mainly family-sized, self-sufficient.

3.2.4 Biodiversity values of plant resources of Ba Vi National Park

Ba Vi is a center of diversity of medicinal species

The diversity of plant species along with their evolutionary history undervarious ecological conditions have generated an affluent plant resource which is vitalfor human life Ba Vi is one of the places endowed by nature with a profuse plantresource including medicinal plant one According to preliminary statistics, there are

up to 304 species of medicinal plants at Ba Vi, amounting to over 27% of totalspecies in the flora (detailed statistics in the list of plants in the Appendix) Amongthem, there a lot of plants very valuable, used widely and efficiently for herbalism.Here are 218 typial medicinal species at Ba Vi:

Table 6 Medicinal plants of the Ba Vi

1 Lycopodiella cernua (L.) Franco et Vasc. Thông đất

2 Selaginella delicatula (Desv.) Alston Quyển bá yếu

3 Selaginella uncinata (Desv.) Spring Quyển bá móc

6 Angiopteris evecta (J Forst.) Hoffm. Móng ngựa lá to

15 Celosia argentea L var cristata (L.)

Kuntze

Mào gà đỏ

16 Choerospondias axillaris (Roxb.) Burtt et

25 Kibatalia macrophylla (Pierre in Planch

ex Hua) Woodson (Kibatalia anceps

(Dunn et Williams) Woods)

Thần linh lá to

26 Rauvolfia serpentina (L.) Benth ex Kurz Ba gạc ấn độ

27 Rauvolfia verticillata (Lour.) Baill. Ba gạc lá vòng

31 Schefflera elliptica (Blume) Harms. Chân chim

32 Schefflera heptaphylla (L.) Frodin (S

octophylla (Lour.) Harms in Engl &

Prantl)

Đáng chân chim

34 Trevesia palmata (Roxb et Lindl.) Vis. Đu đủ rừng

56 Oroxylum indicum (L.)Vent. Núc nác

59 Raphanus sativus var longipinnatus

Baill

Cải củ

60 Canarium album (Lour.) Raeush ex DC. Trám trắng

63 Sambucus javanica Reinw ex Blume

67 Gymnopetalum cochinchinensis (Lour.)

Kurz

Cứt quạ

69 Momordica cochinchinensis (Lour.)

72 Alchornea rugosa (Lour.) Muell.-Argent Đom đóm

73 Alchornea trewioides (Benth.)

Muell.-Argent

Vông đỏ quả trơn

82 Bowringia callicarpa Champ ex Benth. Dây bánh nem

94 Leucaena leucocephala (Lam.) de Wit Keo dậu

96 Millettia reticulata Benth. Mát mạng

97 Millettia speciosa Champ ex Benth. Dây sâm nam

102 Flacourtia jangomas (Lour.) Raeusch. Mùng quân trắng

104 Elsholtzia blanda (Benth.) Benth. Kinh giới rừng

105 Elsholtzia ciliata (Thunb.) Hyland. Kinh giới

108 Mentha arvensis L var javanica Hook.f. Bạc hà

112 Cinnamomum cassia (Ness) Ness et

128 Artocarpus tonkinensis A.Chev ex

130 Ficus heterophylla L.f var heterophylla Vú bò lá to

139 Jasminum sambac (L.) Aiton Hoa nhài

149 Carrallia brachiata (Lour.) Merr. Trúc tiết

150 Eriobotrya japonica (Thunb.) Lindl. Tì bà

153 Canthium dicoccum (Gaertn.) Teysm et

156 Hedyotis capitellata Wall ex G.Don An điền đầu

160 Mussaenda cambodiana Pierre ex Pitard Bướm bạc cambốt

166 Citrus aurantifolia (C.Christm & Panzer)

Swingle

Chanh

167 Citrus medica var sarcodactylis (Sieb.)

171 Fortunella japonica (Thunb.) Swingle Quất

181 Boehmeria nivea (L.) Gaudin Gai

183 Clerodendrum japonicum (Thunb.) Sweet

(C kaempferi (Jack) Sieb ex Steyd.) Xích đồng nam

184 Clerodendron petasites (Lour.) Moore Bạch đồng nam

191 Allium odorum L (A tuberosum Rottler

196 Homalomena occulta (Lour.) Schott Thiên niên kiện

200 Dioscorea persimilis Prain et Burkill Củ mài

201 Peliosanthes teta Andre' subsp teta Sâm cau

204 Chrysopogon aciculatus (Retz.) Trin. Cỏ may

208 Thysanolaena maxima (Roxb.) Kuntze Cỏ chít

214 Amomum villosum Lour (A

echinosphaerum K Schum ex Gagnep.)

Sa nhân

In addition to ample number of medicinal species number, their uses are alsovarious Some major groups of uses are listed as follows: