Tóm tắt luận án: Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.

Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.Ve giáp (Acari: Oribatida) ở hệ sinh thái đất cao nguyên Mộc Châu, tỉnh Sơn La.

MINISTRY OF EDUCATION AND TRAINING

HA NOI NATIONAL UNIVERSITY OF EDUCATION

SUMMARY OF PH.D THESIS IN BIOLOGY

Ha Noi - 2022

AT HANOI NATIONAL UNIVERSITY OF EDUCATION

Scientific Advisor: Prof D.Sc Vu Quang Manh

Referee 1: Assoc Prof Dr Nguyen Van Quang

Organization: Hanoi University of Sciences-Vietnam National University, Hanoi

Referee 2: Assoc Prof Dr Nguyen Thi Phuong Lien

Organization: Vietnam Academy of Sciences and Technology

Referee 3: Assoc Prof Dr Pham Dinh Sac

Organization: Vietnam National Museum of Nature

The thesis will be reported at the school assessment council

at Ha Noi National University of education

on date month the year 2022

The thesis can be found at:

- National Library of Vietnam

- Library of Hanoi National University of Education

INTRODUCTION

1 Scientific basis and importance of research issues

Soil microarthropods, especially oribatid mites (Acari: Oribatida) are an important component of soil biodiversity, playing an important role in the biological processes that take place in the soil ecosystem Soil oribatid community structures and their changes according to species diversity, population densities as well as vertical and partial distributions, are related to ecosystem conditions Therefore, an analysis of the oribatid community structures as bioindicators of soil quality, and as a factor that can contribute to the sustainable development of the soil ecosystem is a problem of great scientific and practical significance Due to their vital importance, oribatid community structures have been studied actively throughout the world Studies on Vietnam's oribatid community structures (Acari: Oribatida) are not enough, especially those taking part in the Northwest mountainous region The tea plantation at Moc Chau highland area is a good model for this study purpose Based on the scientific and practical importance, my Ph.D proposed study project is:

Oribatid mites (Acari: Oribatida) in the soil ecosystems at the Moc Chau plateau, Son

La province

2 Objectives of the study

To study species diversity and the change of the Oribatid community structure related to some natural factors and human impact in soil ecosystem at the Moc Chau plateau; and as the scientific basis for sustainable management biodiversity resources and soil ecosystem in Vietnam

3 Research content

1 To study the species diversity and taxonomic structure of the oribatid mite (Acari: Oribatida) community in the soil ecosystem at the Moc Chau plateau, Son La province and compare with some related areas

2 To study community structure of the oribatid mite (Acari: Oribatida) and the change according to five habitats: (a) Natural forest, (b) Man-made forest, (c) Scrub and grassland, (d) Cultivated land with perennial crops and (e) Agricultural land with annual crops

3 To study the community structure of the oribatid mite (Acari: Oribatida) and the change

in the years, and the cycle of day - night

4 First step role evaluation of the oribatid mite (Acari: Oribatida) in the soil ecosystem of the study area

4 New contributions of the thesis

1 The thesis has produced a full list have 151 of known species of the oribatid mite community, belonging to 94 genera, 49 families and 29 order families in the Moc Chau plateau, Son La province Recording 62 species for the first time for the fauna of oribatid mite in Moc Chau plateau, among them 44 species for the first recorded of Vietnam

2 Adding new data on the classification structure of oribatid communes in the study area were analyzed according to level family, genera, species, and compared with the Northeast Red river delta, and Northcentral region of Vietnam

3 Adding new data on the structure of the oribatid commune according to the ecological indicators including the number of species (S), individual average density, species abundance (d), species diversity (H’), Jaccard index (J’), Simpson index (1-lambda) Determining community structures have changed through habitats following the decline of forest cover, through the

seasonal cycle of the years, through the cycle of day and night

4 The study has determined six dominant species in the study area, including Arcoppia arcualis (Berlese, 1913), Rostrozetes ovulum (Berlese, 1908), Scheloribates mahunkai Subias,

2010, Perxylobates vietnamensis (Jeleva&Vu, 1987), Masthermannia mamillaris (Berlese, 1904)

và Tectocepheus minor Berlese, 1903 They can be considered as biological indicators, of the

effects of natural factors and human impact on the soil ecosystem in the study area

5 The layout of the thesis

The thesis consists of 132 pages, 3 opening pages, 28 overview pages, 12 pages of time, location and research method, 87 pages of results and discussions, 2 pages of conclusions The thesis has 16 tables and 28 pictures, 4 maps, 1 diagram There are 19 reference pages with 41 Vietnamese documents, 115 English documents and 24 other foreign language documents

CHAPTER 1: OVERVIEW 1.1 Overview of research on Oribatid mites (Acari: Oribatida) in the world

The fauna oribatid of the world currently knows about 11,207 species and subspecies, in more than 1,300 genera and 163 families (Subias, 2020) Europe is the birthplace of this major research with the first studies of Hooke (1665), Koch (1835) up to now, the number of researches works in this continent is still the most In Asia, America, Africa, Australia, the research was studied later, but the number of works also increased rapidly The current trend is to study the oribatid mites in Asia, especially in the tropical regions Research in the Arctic and Antarctica is less than in other parts of the world Research on oribatid mites in island areas is getting more and more attention

The main research directions for oribatid mites in the world are fauna research, species diversity investigation is still being increased, besides the publication and description of new species for science and biological characteristics of the oribatid mites Research on morphology

- anatomy, biological characteristics - development, reproduction, behavior, paleontology to investigate evolution and phylogeny, use of molecular genetics in taxonomy and evolution, origin and evolutionary tendency, classification, the ecological relationship of the oribatid with the environment, special attention to the role and significance of the bioindicator of they as well as the effects of some groups such as infectious vectors, parasitic helminths The biological geography, recently, the number of species of the oribatid mites recorded by geographical regions

in the world decreased in the order: 3.891 Paleárticas > 2.576 Orientales (India - Malaysia) > 2.312 Neotropicales > 1.939 Etiopicas> 1.488 Australians > 1.523 Neárticas > 137 Antárticas and Subantárticas (Subias, 2020)

1.2 Study on the oribatida mite (Acari: Oribatida) in Vietnam

Until now, the study of the oribatid mites in Vietnam is about 50 years, it divided into three periods: The period (1967-1986) building the first base for research of the oribatid mites general and Microarthropoda particular in Vietnam This period recorded 73 species Next, the period (1987- 2007) formed an in-depth research direction on the ecosystem and fauna research of the soil Arthropoda with two dominant groups are Oribatida and Collembola The research areas have been expanded, conclusion recorded 150 species The period 2008 - now The development

of the team of young qualified researchers is strongly increasing, the number of species oribatid recorded is highest in the period with 726 species belonging to 245 genera, 90 families and 41 order families

The research of the fauna oribatid Vietnam was conducted from North to South, but the most concentrated research in Northeast region and Red river detail region, Northwest has a small number of studies Recently, the East region and Southwest of Vietnam is studied a lot by foreign scientists

The main research direction in Vietnam includes species diversity survey, description and announce new species, the community structure of the oribatid mites related to the change of the environmental conditions, research for the role and significance of the bioindicator, determining the possibility of parasitic organisms carrying vector of the oribatid mites and the characteristics biological geography of the oribatid fauna

1.3 Study on oribatida mite (Acari: Oribatida) in Moc Chau plateau, Son La province

The study area is in Moc Chau district, Son La province, in the Northwest region of Vietnam In Son La province, there have been some studies by Vu Quang Manh et al., to evaluate the density and diversity of species composition, animal location characteristics, and the role of the group of the oribatid mites and springtails in the Northwest of Vietnam, in the period 1982,

1984, 1987 - 1996, 2000, 2003 - 2006, in Son La city and some places in Moc Chau district, including mount Pha Luong (1507 m high) in Tan Xuan commune, Xuan Nha nature reserve and

Na Hieng village in Xuan Nha commune Up to now, all the research on the oribatid mites has a little in the study area

1.4 Overview of natural and social conditions of the study area

1.4.1 Geographic location, topography and soil

Moc Chau is a mountainous district in the southeast of Son La province The average altitude above sea level is 1,050 m Geographic coordinates 20o63' N and 104o30' - 105o7' E Moc Chau has a Karst, the total area of natural land is 108,166 ha There are two basic types of soil: reddish-brown and ancient alluvial soil

1.4.2 Climate and hydrology

Due to the profound influence of the northeast monsoon, there is a subtropical climate element here The climate is cool, the average temperature is from 18oC to 23oC, the difference between day and night is 8oC; The average humidity is 85%, the average annual rainfall ranges from 1,400 mm to 1,500 mm Winters are cold and often get frost Moc Chau is the meeting place

of many rivers and streams, including the Da River flowing through which is a large river located

in the north of the district

1.4.3 Animal - plant resources and human factor

Area of special-use forest in Moc Chau is 2,338,112 ha; protection forest 27,690,867 ha; production forest 23,052,472 ha Forest cover 47% of the total natural area There are about 456 species

of plants in 4 branches and 48 species of wildlife belonging to 19 families, 8 orders

Moc Chau district has two towns, namely Nong Truong and Moc Chau The agriculture here develops in association with the cultivation of sloping land in which tea cultivation is popular Also, the climate here is an advantage for people to develop their economy with tropical flowers, fruits, and vegetables

CHAPTER 2 TIME, LOCATION AND RESEARCH METHOD

2.1 Subject, place and time of study

Subjects of study: The oribatids mites belonging to the Oribatida order, the Acari sub-class (Arachnida), class, the Arthropod sub-phylum (Chelicerata), the Arthropods phylum (Arthropoda), and the domain animals (Animalia)

Study location and time: The study began from 2016 to 2020, in the soil ecosystem of Moc Chau district, Son La province, according to the following contents: Collecting samples according

to the five habitat types of the study area: natural forests, man-made forest, scrub and grassland, cultivated land with perennial crops, and agricultural land with annual crops Sampling in four seasons (spring - summer - autumn - winter) and cycle day and night (6:00 - 12:00 - 18:00 - 24:00)

at the tea planting landscape of the study area Add more the qualitative samples collected at the man-made forest habitat in some places in Chieng Hac, Phieng Luong, Tan Lap, Cho Long, Chieng Son communes

The soil samples after being collected were filtered, analyzed, and classified for the oribatid mites at the practice room of the Department of Animals - Department of Biology, Center for Research and Education of Biodiversity (CEBRED) Hanoi National University of Education, some samples of the oribatid mites were analyzed with colleagues at the Bulgarian Academy of Sciences, Sofia

2.2 Research Methods

2.2.1 Soil sample collection

Follow the method of Ghilarov & Krivolutsky (1975) Depending on the characteristics of the studied habitat, samples are collected from 3-5 vertical deep layers of the soil ecosystem: (0) The layer of Forest litter samples; (-1) Surface layer in the ground, 0-10cm deep; (-2) The middle soil layer is deep in the ground, > 10-20cm; (-3) Soil layer deep in the ground, >20-30cm For the floor (0) collection with surface area (25x25) cm² For soil layers from (-1)  (-3) will be cut

by a metal box of size (5x5x10) cm3, surface area 25cm2 Each location was repeated 5-7 times,

a distance of about 3-5m The total number of soil samples collected is 302 samples

2.2.2 Oribatid extraction

Modifications of Berlese-Tullgren funnels were used for the extraction of oribatid mites from the obtained materials, as described in detail by Edwards (1991) An extraction lasted 7 days

in the laboratory at a normal condition of 27 ˚C -32˚C Extracted oribatid mites were preserved

in 70% ethanol Then under a microscope they were sorted and counted adults only Oribatids were mounted in lactic acid on temporary cavity slides, and identified to a species level as possible

2.2.3 Methods of analysis and species identification of Oribatid

Identification of species names was performed on microscopy with a room degree of 100X First, based on morphological characteristics separating the mites into groups of similar shapes Then transfer each oribatid to a concave microscope slide, a small amount of lactic acid that partially covered the depression, and cover the lamination Use your hands to move the lamel

40-to observe the oribatid mites in different positions with different magnifications Oribatid species were identified and classified according to Ghiljarov and Krivoluskij (1975), Balogh and Balogh (1992), Schatz et al (2011), and Subias (2020)

2.2.4 Methods of analysis and data processing

The structure of species composition, distribution characteristics of the oribatid mites populations were analyzed according to the mathematical-statistical method, using Primer V6.1.6 software and excel tool to calculate ecological indicators including species abundance (d), Peilou index (J '), Simpson's dominance index (1 - λ), Shannon-Weiner index (H'), Bray-Curtis similarity coefficient and dominance curve K-dominance

CHAPTER 3: RESEARCH RESULTS AND DISCUSSION 3.1 Diversity of the composition of Oribatid mited (Acari: Oribatida) in the study area

3.1.1 List of the composition of oribatid mites in the study area

Research results of 302 sample soils with 3728 individuals are obtained in the study area

It has recorded 151 species, of which 21 species were newly identified to genus "sp.", Belonging

to 94 genera, 49 families, and 29 families This result contributes 44 new species to the Viet Nam Fauna (accounting for 29.14% of the total species) and 62 new species to the Moc Chau plateau, Son La province (accounting for 41.06% of the total species) The results are presented in Table 3.1

Table 3.1 Diversity of species composition and distribution characteristics of the oribatid according to some major natural and human factors in the soil ecosystem

Moc Chau Plateau, Son La Province

Ordinal

Distribution characteristics

Habitat (a, b,

c, d, e)

Seasons (X, H,

T, Đ)

Day and night cycle (6:00, 12:00, 18:00, 24:00)

Soil vertical layers (+1, 0, -

1, -2, -3)

Number of individuals (+, ++, +++)

New species

Ordinal

Distribution characteristics

Habitat (a, b,

c, d, e)

Seasons (X, H,

T, Đ)

Day and night cycle (6:00, 12:00, 18:00, 24:00)

Soil vertical layers (+1, 0, -

1, -2, -3)

Number of individuals (+, ++, +++)

New species

Ordinal

Distribution characteristics

Habitat (a, b,

c, d, e)

Seasons (X, H,

T, Đ)

Day and night cycle (6:00, 12:00, 18:00, 24:00)

Soil vertical layers (+1, 0, -

1, -2, -3)

Number of individuals (+, ++, +++)

New species

19 Apoplophora pantotrema (Berlese,

25 Acrotritia sinensis Jacot, 1923

(Rhysotritia rasile Mahunka, 1982)

26 Microtritia tropica Märkel, 1964 X, T, Đ 6h, 12h,

18h, 24h, đt12h, đt24h

27 Hoplophorella hamata (Ewing, 1909)

(Hoplophorella cuneiseta Mahunka,

Ordinal

Distribution characteristics

Habitat (a, b,

c, d, e)

Seasons (X, H,

T, Đ)

Day and night cycle (6:00, 12:00, 18:00, 24:00)

Soil vertical layers (+1, 0, -

1, -2, -3)

Number of individuals (+, ++, +++)

New species

36 Nothrus pulchellus (Berlese, 1910)

(=Nothrus parvus Sitnikova, 1975)

Ordinal

Distribution characteristics

Habitat (a, b,

c, d, e)

Seasons (X, H,

T, Đ)

Day and night cycle (6:00, 12:00, 18:00, 24:00)

Soil vertical layers (+1, 0, -

1, -2, -3)

Number of individuals (+, ++, +++)

New species

43 Cultroribula lata Aoki, 1961 a, b, c, d,

Ordinal

Distribution characteristics

Habitat (a, b,

c, d, e)

Seasons (X, H,

T, Đ)

Day and night cycle (6:00, 12:00, 18:00, 24:00)

Soil vertical layers (+1, 0, -

1, -2, -3)

Number of individuals (+, ++, +++)

New species

58 Multioppia tamdao Mahunka, 1988 a, b, c, d,

e, đt b

X, T, Đ 6h, 12h,

18h, 24h, đt6h

66 Microppia minusminus (Paoli, 1908)

(Oppia minutissima Sellnick, 1950)

67 Lauroppia neerlandica (Oudemans,

0, -1, -2, -3

Ordinal

Distribution characteristics

Habitat (a, b,

c, d, e)

Seasons (X, H,

T, Đ)

Day and night cycle (6:00, 12:00, 18:00, 24:00)

Soil vertical layers (+1, 0, -

1, -2, -3)

Number of individuals (+, ++, +++)

New species

74 Machuella ventrisetosa Hammer,