INTRODUCTION
Forests are invaluable ecosystems that provide rare products and essential health benefits through various medicinal herbs They play a critical role in climate regulation and protect biodiversity, acting as the planet's lungs by purifying the air and supplying oxygen vital for human survival Additionally, forests serve as windbreaks, coastal sand compartments, and flood prevention systems in mountainous regions, helping to mitigate natural disasters Furthermore, they are rich natural reserves, home to thousands of bird species and rare animals, offering endless opportunities for biological research.
The rising demand for resources has created significant contradictions between nature conservation and development To address this conflict and meet human needs sustainably, it is essential to utilize resources, particularly forest resources, more effectively Unfortunately, forests have faced overexploitation, natural disasters have caused devastation, and climate change poses a serious threat to life on Earth.
According to the Food and Agriculture Organization (FAO), deforestation is causing the loss of 130,000 km² of forests annually, leading to a significant decline in biodiversity and the extinction of approximately 100 species each day Key factors contributing to this deforestation include the conversion of forests into agricultural land, land settlement, unsustainable timber harvesting, and inefficient land management practices Additionally, the World Bank highlights that deforestation accounts for 20% of global greenhouse gas emissions, underscoring its critical role in climate change.
Vietnam is experiencing a significant decline in forest cover, with the quality of the remaining natural forests deteriorating In 1943, forests spanned nearly 15 million hectares, accounting for 43% of the country's natural area However, the prolonged 30-year war, driven by various factors, severely impacted the forest ecosystem.
7 areas shrink rapidly, until 1993, only 9.5 million hectares remaining, covering 28% of the natural land of the country
Sustainable economic development requires balancing growth with the protection of natural resources and the environment, a key concern for many managers To achieve this balance, it is essential to investigate, monitor, and analyze fluctuations in forest areas Annual reports on the current state and changes in forest areas are crucial for forest managers to effectively manage and protect these vital ecosystems.
The urgent need for the protection and sustainable development of forest resources is recognized globally, with a focus on ecological stability, wood quality, and biodiversity conservation In Vietnam, as in many countries, natural forests are facing degradation, prompting a critical assessment of plant resources at Ba Vi National Park My thesis aims to evaluate fluctuations in these resources by analyzing historical survey data to determine the current status of forest areas and plant diversity This analysis will clarify whether the condition of forest plant resources has improved or declined over the years and assess the adequacy of existing forest protection measures Based on these findings, I will propose strategies to enhance forest management and sustainability.
AN OVERVIEW OF THE RESEARCH
In the world
On March 11, 2010, an international conference focused on major global forest areas was held in France, where participants addressed strategies to combat deforestation A key topic was the $3.5 billion financing commitment from six countries—France, Australia, Japan, Britain, Norway, and the US—aimed at supporting developing nations in reducing greenhouse gas emissions linked to deforestation, a pledge initially made during the Copenhagen summit in December 2009.
In his opening speech at the conference, French President Nicolas Sarkozy urged both developed and developing nations to unite in the fight against global deforestation, aiming for a 50% reduction by 2020 and complete elimination by 2030 He emphasized the importance of linking deforestation efforts to the livelihood security of impoverished communities, stating, "It is absurd to choose between protecting forests and the poverty of people living in and around these areas." Sarkozy called for research on the impacts of anti-deforestation programs on food security to identify effective solutions that balance environmental protection with the needs of vulnerable populations.
In 2011, the United Nations declared the International Year of the Forest to promote awareness of sustainable forest management and conservation, aiming to benefit both current and future generations.
The primary goal is to foster the management, conservation, and sustainable development of diverse forest types, while strengthening long-term political commitment among nations in line with the 1992 Rio Declaration and the Agenda 21 principles aimed at combating deforestation.
The UN aims to significantly increase global forest cover through sustainable forest management during the International Year of the Forest This includes initiatives for protection, restoration, reforestation, afforestation, and efforts to prevent forest degradation Additionally, the initiative seeks to mitigate the economic, social, and environmental impacts on forests by enhancing the livelihoods of communities that rely on them.
In Vietnam
On 24 September 2010, the Government of Vietnam issued a "Decree 99/2010 / ND-
The Decree on the policy for payment for forest environmental services mandates that state agencies, organizations, households, and individuals benefiting from forest resources must compensate the suppliers, including organizations, individuals, and forest communities Extensive research in Vietnam has focused on assessing forest vegetation, emphasizing its current status and development patterns, and proposing solutions for protection and restoration Notable projects have emerged from these proposals, highlighting the importance of sustainable forest management.
- Vu Tien Hinh (1991), "The regeneration characteristics of the natural forest ", Journal of Forestry
- Le Đong Tan (2000), “Study the natural recovery process some plant communities after cultivation in Son La serve the zoning”, Biology doctoral thesis, Hanoi
- Nguyen Tu Uong, Do Van Ban(2010) “Study forest plant resources in Vietnam”
- Tran Minh Tuan (2014) Research of diversity of vascular plants in Ba Vi National Park
The research on forest resource changes in Tran Ngu Phuong and Thai Van Trung highlights the varying laws of forest structure, focusing on the arrangement of trees both vertically and horizontally within the space.
RESEARCH OBJECTIVES AND METHOD
Goals and objectives
- Goal: Improve the effectiveness of management of forest resources in Ba Vi National Park
The analysis of survey results, in conjunction with historical data, reveals the trends in forest changes over the years, including variations in forest area and plant resources, while also facilitating the calculation of biodiversity indicators within the study area.
[2] Determining the causes of declining in plant resources and propose measurements to conserve plant diversity in Ba Vi National Park.
Study site and scope
- Study site: Ecological Restoration zone of Ba Vi National Park
- Forest type: Secondary natural forest in Ba Vi
Ba Vi National Park features a humid tropical climate influenced by its northern latitude and monsoon patterns, with an annual average temperature of 23.4°C, peaking at 42°C and dropping to as low as 2.7°C At elevations of 400m and above 1,000m, temperatures average 20.6°C and 16°C, respectively, with winter lows occasionally reaching 0.2°C The park receives approximately 2,500mm of rainfall annually, primarily between July and August, and maintains an air humidity of around 86.1% at 400m ASL, resulting in no distinct dry season These climatic conditions contribute to a rich ecological diversity, making Ba Vi National Park a sought-after destination for tourists Additionally, its higher elevation compared to Cuc Phuong National Park offers cooler weather and a greater variety of flora and fauna.
Ba Vi features a range of medium and low mountains, alongside notable high peaks including Vua Peak at 1,296 meters above sea level, Tan Vien Peak at 1,227 meters, Ngoc Hoa Peak at 1,131 meters, and Vien Nam Peak at 1,031 meters.
The Ba Vi mountain range features two primary ridges: the first extends 9 km from Oi stream to Dat bridge, passing through Vien and Lobster peak, while the second ridge stretches 11 km from Yen Vien Son to Quit mountain, reaching into Hoa Binh province The park is characterized by steep slopes, averaging around 25 degrees, which increase to an average of 35 degrees at elevations above 400 meters.
Figure 3.1 The location of study site
Methodologies
Over the past decade, a comprehensive assessment of forest vegetation resources at Ba Vi National Park has been conducted This phase involves the collection, examination, and evaluation of existing documentation and data, alongside field surveys tailored to meet the study's objectives The relevant data from the study area will be carefully selected and utilized for further analysis.
_ Collect data variation of plant resources in 10 years and the natural conditions, economic, and social studies area
_ Collect documents and records related to the service, the study of the subject
3.3.2 Field survey methods a) Setting up plots: Principle: plot area is the minimum area, relatively homogenous forest to ensure that the research data to meet the requirements and the research objectives proposed
When establishing fixed plots for forest representation, it's essential to select areas with relatively homogeneous terrain and evenly distributed trees that exhibit normal growth Avoid placing plots in cramped locations, such as narrow slots, on steep inclines, or along trails.
Selecting survey lines and research sites is crucial for capturing the diverse flora of the entire study area This selection process is informed by topographic maps, land use status maps of Ba Vi National Park, and insights from previous surveys.
The area and shape of sample plots: plot has the area of 5000m 2 (40m x 125m) in the north slopes of Mount Ba Vi
Structure of sample plots: multi-scale sampling plots
For each sample plot we will arrange as below:
Figure 3.2 Sample plot b) Method of investigation for fluctuations in forest state, fluctuations in forest area:
A preliminary survey of the forests at Ba Vi National Park was conducted to assess the current state of the forest over a 10-year period This involved collecting and tabulating data from previous years to analyze fluctuations in forested areas The study focused on comparing data from the years 2005 and 2010 with that of 2015.
Time Natural forest Plantation forest Area (ha)
2015 c) Research methodology of fluctuations of forest plants in Ba Vi National Park
The high tree layer, characterized by trees with crowns that form the primary forest canopy, consists of species with a diameter at breast height (DBH) exceeding 6 cm This layer plays a crucial role in forest ecology and silvicultural management.
*The indicators to be measured at tree layer:
_ Measuring the diameter at breast height (DBH) of all trees in plots with caliper, measured in two perpendicular dimensions and took the average
_ Measuring the tree high (H) and height under crown (h) of all trees in plots by height measuring machine Vertex
_ Measuring the diameter of tree crown (Dc) of all trees in plots by tape
_ Surveying the state of growth in two levels of good and bad (good growth trees with a good shape, foliage are not twisted, topless; on the contrary is bad)
When examining the tree layer, it's essential to assess the lower forest layer as well Each small tree should be numbered or marked with paint, and if the trees are too small, a numbered sign should be hung to ensure proper identification.
To accurately identify the species name, it is essential to analyze last year's survey results and compare them with the position diagram to assess the current status Any detected errors must be corrected or supplemented to ensure data integrity.
The measurement of growth indicators in trees is performed similarly to that of high tree layers This involves the precise assessment of various metrics, including the diameter at breast height (DBH), tree height (Hand h), crown diameter (Dc), and overall tree quality.
16 d) Methods to investigate the biodiversity indicators
This study utilized quantitative analysis to assess biological diversity through key indices such as the Shannon index (H) and Importance Value Index (IVI) A high value in these indices indicates a strong correlation between high diversity and significant biological value Implementing these research methods is essential for developing a comprehensive database that supports conservation efforts, policy-making, and the sustainable management of biodiversity resources.
To identify indicators of biodiversity of Ba Vi National Park, using survey methods according to plots At each plot, measure and collect information on:
_ Species composition (with sampling plant to specify the name for a number of species required); determine the name of the trees
_ The number of individuals for each species, diameter of each individual
- Determining important value IV index of tree species (IV, %) by using formula (1)
- IV%: important value index of tree species
- N%: percentage of the number of tree species
- G%: percentage of basal area of tree species Basal area (BA) = π (DBH/2) 2
- Determining diversity index of tree species, include: Formula (2), (3), (4), (5)
Where: d: diversity indicator Margalef S: total species in the plot
N: total individual in the plot + Diversity indicator Shannon - Wiener (H’)
H’: indicator Shannon - Wiener S: the number of species in the plot
N: total individual in the plot ni: the number of individual of i specie + Indicator Simpson (L - Lambada)
RESEARCH RESULTS AND DISCUSSIONS
Fluctuations in forest state and in forest area
Ba Vi National Park encompasses a total forest area of 10,814.6 hectares, divided into two main functional zones The Strict Protection Zone, covering 1,648.6 hectares (15.2% of the park), is dedicated to preserving the forest's natural state, prohibiting any activities that could alter its composition This zone, located at elevations above 400 meters, primarily supports scientific research and tourism In contrast, the Ecological Restoration Zones, comprising 8,823.5 hectares (81.6% of the park), lie below 400 meters and include 7,045.9 hectares of forested land, with 4,932.1 hectares classified as natural forests Additionally, there are 1,569.5 hectares of non-forest land within this zone The park's diverse forest types include areas of average and poor quality forests, particularly concentrated in three mountainous regions totaling 883.9 hectares.
Table 4.1 Comparing fluctuations of total forest area, natural forests area, and plantation forests area
Time period Natural forest (ha) Plantation forest (ha) Total area (ha)
Base on data collected, tabulated comparison showing forest area over the years to compare, evaluate, and review the status, condition of forests in Ba Vi National Park
*Review and explain fluctuations of types of forest
Ba Vi National Park has maintained a relatively stable forest quality over the past decade, experiencing only a slight decline From 2005 to 2015, the forest land area increased from 7,039.7 hectares to 7,045.9 hectares, indicating a positive trend in forest preservation.
Natural forests: In 2005, natural forests in Ba Vi National Park is 4,987.4 ha reached 45.6% coverage rate of forests; natural forests in 2010 was only 4,959.4 hectares, and from
2010 to 2015, decreased from 4,959.4 ha to 4,932.1 ha Thus, after 10 years, natural forest area have decreased 55.3 ha
The decline of natural forests is driven by several factors, including population growth and increased demand for firewood, timber, food crops, and industrial development Illegal logging remains a significant issue, with rangers reporting 30 cases and a loss of 38.1 m³ of wood from 2005 to 2015 Additionally, practices such as deforestation, slash-and-burn agriculture, and forest fires have exacerbated the situation Ineffective forest protection measures and uncontrolled encroachment further threaten these ecosystems The ongoing illegal activities have not only led to the direct destruction of species but have also altered the environment, diminishing the regeneration capacity of vegetation and reducing plant diversity in the region.
As of 2005, the area of plantation forests was 2,052.3 hectares, with a significant increase in afforestation rates observed from 2010 onwards, totaling an impressive 61.5 hectares over the past decade This growth is attributed to a thriving planting movement across various regions, alongside an ambitious plan to plant 5 million hectares of forestry at Ba Vi National Park Currently, the total forest area has expanded to 7,045.9 hectares, representing 65.15% of the overall forest area.
Fluctuations of forest plants in Ba Vi National Park
The high tree layer in forests significantly influences environmental conditions and the growth of native tree species beneath its canopy A survey conducted across ten plots in the research area identified two dominant species: Vai guoc (Xerospermum noronhianum) and Khao tang (Nothaphoebe baviensis).
4.2.1 Fluctuations in density of high tree layer
Density is a crucial indicator for assessing the high tree layer The frequency of Vai guoc is observed in 10 out of 10 plots, while Khao tang appears in 9 out of 10 plots The calculations of the high tree layer from 2005 to 2015 are detailed in Table 4.2.
Table 4.2.The density of high tree layer of regional in phase 2005 to 2015
The forest in the study area has maintained a high tree layer density, with an average increase of 1 to 2 trees per 500m² plot The highest density recorded was 10 trees in plot #6, while plot #8 had no trees This increase can be attributed to the well-protected status of the area, which has remained unaffected by deforestation, allowing the perennial woody plants to continue growing and thriving.
The upper layer of this forest consists of trees that have developed naturally, free from human influence However, the increasing demand for light and nutrients from the lower canopy trees is being hindered by the density of the upper layer, potentially negatively impacting the growth and development of these understory trees.
4.2.2 Fluctuations diameter at breast height (DBH) of high tree layer
The diameter at breast height (DBH) serves as a crucial indicator of forest tree growth, reflecting the impact of silvicultural techniques and the adaptability of species to their environment As a vital metric in the investigation and research of forest resources, DBH demonstrates consistent horizontal growth, with trees showing an increase in diameter over the years without any signs of decline For this study, I selected representative trees from various species to serve as typical indicators of DBH The data collected from research plots during the period of 2005 to 2015 is presented in Table 4.2.
Table 4.3 Fluctuations diameter at breast height (DBH) of high tree layer in phase 2005 to 2015
Tree names Plots number Years
According to Table 4.2, the findings indicate that each research plot shows an increase in diameter at breast height over time, suggesting that the high tree layer in the area is still in the growth stage.
We can see that the growth rate is relatively stable
In 2015, the diameter at breast height (DBH) varied significantly among different plots, with the highest measurement recorded at 56.1 cm in plot 2 and the lowest at 8.6 cm in plot 7 Generally, a higher DBH indicates a greater economic value of the forest, as it correlates with increased tree volume and age It is important to note that DBH typically develops at a slower rate compared to tree height (H).
The variance between the plots ranges from 5.3 to 9.2, primarily due to the natural growth of forests, with minimal impact from previous years Additionally, the age disparity of trees, ranging from 15 to 24 years, contributes to differences in Diameter at Breast Height (DBH).
4.2.3 The fluctuation the trees high (H) of high tree layer
Tree height serves as a crucial metric in assessing forest growth, revealing not only the development of individual trees but also the overall structure of the forest in a vertical context By analyzing tree height, we can discern various characteristics of the forest ecosystem.
H of high tree layer in the period (2005-2015) are shown in Table 4.2
Table 4.4 The average height of high tree layer in phase 2005 to 2015
Tree names Plots number Years
From table 4.3 we can see that: every year, the height of high tree layer in the region still rising, suggesting that tree growth and normal development
Over a five-year research period, the height of trees in the plots exhibited significant fluctuations, with the high tree layer measuring between 8.4 m and 25.0 m in 2015 The variance remained relatively stable, ranging from 2.5 to 3.7, indicating healthy plant growth and consistent height increase This height allows the high tree layer to dominate the canopy, effectively shielding lower tree layers and reducing light intensity, which benefits smaller shade-tolerant plants Additionally, the considerable variation in the height of the high tree layer suggests rapid plant growth driven by favorable climatic conditions and minimal external disturbances.
Investigative biodiversity indicators
Species with ecological significance in a community possess an important value index (IV %) of 5% or higher A 2015 study revealed that the number of species meeting this criterion varied between 2 and 10 within these communities Additionally, important value indices differ among species and fluctuate over the years.
In 10 plots there are 15 species that have highest IV%, in which 2 species have ecological significance, Khao tang (Nothaphoebe baviensis) and Re chum (Cinnamomum glaucescens) have the highest IV% values Percentage of plots where species appeared in varied from 60% to 90% 15 species which have the high important value indices (IV%) are shown in Table 4.4
No Name of species Family IV % (2015) IV % (2005)
1 Khao tang (Nothaphoebe baviensis) Lauraceae 2.54 – 18.51 1.82- 18.78
2 Re chum (Cinnamomum glaucescens) Lauraceae 0.92- 16.55 1.93 – 16.04
3 Ba dau (Croton roxburghii) Euphorbiaceae 2.18 – 12.36 3.24 – 12.04
4 Goi gac (Aphanamixis grandiflora) Meliaceae 1.41 – 8.12 1.91 -10.18
5 Nanh chuot (Cryptocarya lenticellata) Lauraceae 1.14 – 8.99 1.62 – 7.62
6 Tram trang (Eugenia wightiana) Myrtaceae 1.45 – 14.98 1.55 – 14.45
Khao luoi nai (Machilus thunbergii
9 Tram tia (Syzygium baviense) Myrtaceae 0.84 – 10.09 1.72 – 9.77
12 De la tre (Quercus bambusifolia) Fagaceae 1.95 – 9.56 2.34 – 11.04
13 Thung muc (Wrightia laevis) Apocynaceae 2.67 – 7.35 1.83 – 5.22
14 Re gung (Cinnamomum zeylanicum) Lauraceae 1.04 – 6.46 1.61 – 6.94
Vang ve (Adina globiflora Salisb var tonkinensis)
According to Thai Van Trung (2001), the dominant tree species must have IV value
The analysis reveals that 6 out of 10 investigated plots meet the condition of having over 50% ecological significance The index of ecologically significant species (IV%) ranges from 50.64% to 80.88%, highlighting the presence of various species including Khao, Nanh Chuot, Tram Tia, and Vai Guoc.
Re Chum, not only increases the specificity of forest plant communities, but also significance in nature conservation this area
Comparing important indicator between the two stages in 2005 and 2010 we can see that: Five species has highest IV% index are: Khao tang (Nothaphoebe baviensis), Re chum
(Cinnamomum glaucescens), Tram trang (Eugenia wightiana), Vai guoc (Xerospermum noronhianum), and Ba dau (Croton roxburghii) Important value index change not much in two stages
4.3.2 Diversity indices of tree species
Diversity indices of tree species in the studies area in 2005 and 2015 are shown in Table 4.5
Table 4.6 Diversity indices of tree species
Margalef’s Diversity Index (d) indicates the species richness in forest plant communities, with higher values reflecting a greater variety of species and fewer individuals per species In 2015, the index recorded a minimum value of 7.86 in plot 6 and a maximum of 16.02 in plot 10 Similarly, in 2005, the minimum value was 7.31 in plot 3, while the maximum reached 12.99 in plot 10.
The Shannon’s Diversity Index (H’) values ranged from 1.03 to 1.29, with an average of 1.16, indicating low species richness in 2015 In comparison, the values in 2005 varied from 0.95 to 1.25, averaging 1.1, also reflecting low diversity Research suggests that the highest values of H' can reach around 5.0, highlighting the need for increased species richness in these years.
In 2015, the values of Simpson's indices (D) varied between 0.88 and 0.95, averaging 0.91, while in 2005, the values ranged from 0.85 to 0.93, with an average of 0.89 An increase in the value of (D) indicates a greater dominance of species within the ecosystem.
Based on values of 4 indices indicators in Table 4.5 we can see that in two stages in
Between 2005 and 2015, the diversity indices of tree species showed minimal variation In both years, plot 10 exhibited the highest species diversity, while plot 6 in 2015 and plot 3 in 2005 recorded the lowest diversity levels Overall, the study area demonstrates a weak diversity index for tree species.
4.4 Proposed some solutions developed lower forest layer and forest management Ba Vi National Park
In recent years, the forest has developed naturally with minimal human impact, featuring plants that are between 10 to 15 years old Some species exhibit rapid growth and promising potential However, the presence of tall trees is negatively affecting the growth of the lower forest layer.
The lower forest layer, initially adapted to thrive in shaded conditions during their early growth, now faces increased demands for light and nutrients This shift has led to competition with the upper tree layer, which negatively impacts the growth and survival of the forest's lower strata Consequently, a conflict has emerged between the high tree layer and the lower forest layer regarding their respective needs for light and nutrients.
In addition, there is exists a contradiction between physiological needs, the ecology of the low trees layer with the ecological conditions in the region Therefore, research is needed
To identify the optimal physiological and ecological conditions for the growth of various species, it is essential to establish appropriate measurements for the affected individuals This approach will promote the growth and development of plants within the region.
4.5 Propose some solutions to protect and grow diverse plant resources in Ba Vi National Park
Overall protection in Ba Vi National Park is well but still exists some direct and indirect causes deterioration in forest plant resources
The study reveals that direct grazing accounts for 30.7% of land use, highlighting a low awareness of forest conservation at 24% Additionally, only 17% of agricultural land is utilized, while forest exploitation stands at 23.8% The analysis indicates that poverty affects 53% of the population, which is further exacerbated by timber harvesting at 19.8% and slash-and-burn practices at 18.2% Overall, the agricultural land remains a minor area, impacting sustainable land management and forest preservation efforts.
Poverty 53% unknown information fire warning 2% unknown information fire warning 24%
The board and staff of Ba Vi National Park have implemented effective solutions to mitigate forest damage, including enhancing information and communication, investing in agricultural land and infrastructure, and developing land use planning They are also conducting research to apply economic development models for local households, promoting trade development, and upgrading infrastructure for forest fire services Additionally, stricter penalties have been established for illegal logging and intentionally caused forest fires.
Ba Vi National Park features forest areas dominated by high tree layers, primarily consisting of tree species adapted to elevated ecological levels, which enhance land quality and environmental conditions This upper canopy fosters a favorable environment for the lower forest layers to thrive, ensuring a sustainable future for the region's forests The interdependent relationships within the forest ecosystem are crucial, with the high tree layer playing a pivotal role, while the lower layers serve as a potential source for future generations of trees.
The forest in the study area features a well-structured canopy and density, thriving naturally without human intervention Although the basal area and volume of the upper tree layer are substantial, there is a current conflict for space, nutrients, and light with the lower tree layer, highlighting the competition among different forest strata.
Research findings indicate a decline in species diversity, with 61 species recorded in 2015 compared to 56 in 2005 The total number of tree species also increased from 477 in 2005 to 701 in 2015 Additionally, the important value indices of woody species vary among different species and forest plant communities, highlighting the ecological significance of five key species.
(Nothaphoebe baviensis), Re chum (Cinnamomum glaucescens), Tram trang (Eugenia wightiana), Vai guoc (Xerospermum noronhianum), Ba dau (Croton roxburghii)] have high