The thesis aims to obtain data on freshwater crustacean composition in the water bodies of Phong Nha - Ke Bang National Park. Identify the characteristics of quantity distribution of freshwater crustaceans in the study areas along with the changes of this group in terms of space and climate season. Proposing solutions to conservation of specific and important types of SE in limestone areas of Phong Nha and Quang Binh national parks.
0 MINISTRY OF EDUCATION AND TRAINING VIETNAM ACADEMY OF SCIENCE AND TECHNOLOGY GRADUATE UNIVERSITY SCIENCE AND TECHNOLOGY -*** - LE DANH MINH STUDY ON SPECIES COMPOSITION AND DISTRIBUTION CHARACTERISTICS OF FRESH WATER CRUSTACEAN (CRUSTACEA) IN WATER BODIES OF PHONG NHA – KE BANG NATIONAL PARK Major: Zoology Code: 42 01 03 SUMMARY OF BIOLOGY DOCTORAL THESIS HÀ NỘI – 2018 This dissertation is submitted to the Committee of the Graduate University of Science and Technology Supervisors: Asc Prof Dr Ho Thanh Hai Dr Tran Duc Luong Referee 1: Referee 2: Referee 3: The research has been carried out at the Graduate University of Science and Technology Date of Oral Presentation:……,… /…… /2018 Copy of this dissertation is available: National Library of Viet Nam Graduate University of Science and Technology INTRODUCTION The necessity of the research The Decapodal, Copepoda, Cladocera and Ostracoda taxonomy are the popular species of crustaceans in freshwater in general, and in the water bodies of karst in particular The biodiversity of these groups is reflected in the abundance of the species, number of individuals and distribution in the community They play a major role in the food chain and food net of aquatic ecosystem Many species are economically exploitable In the world, many studies on the fauna in general and the freshwater crustaceans in the water bodies of karst in particular, including cave underground water were realised with interestingly results which many new genus and species have been found In Vietnam, for the topographical karst in general and the limestone mountains of Phong Nha-Ke Bang National Park in Quang Binh Province in particular, especially for underground water bodies in the cave underground water bodie there are very few research on biodiversity characteristics, species composition of the aquatic fauna in general and the crustacean group in particular Previous studies on the environment and aquatic life in the Phong Nha-Ke Bang National Park have recorded 33 freshwater crustacean species, of which 12 species are found in the Phong Nha cave Of the species found in the river in the Phong Nha cave, two new Calanoida crustacean species for science are described These new species and genus are currently being considered endemic to Vietnam Certainly, these above results have not fully reflected the species composition and distribution characteristics of freshwater crustaceans in the topographical karst, espcially the cave underground water in the karst of Phong Nha-Ke Bang Therefore, we propose the research topic: "Study on species composition and distribution characteristics of freshwater custacean in water bodies of Phong Nha-Ke Bang National Park" Objective - Having sufficient data on the leading component of freshwater crustaceans in waters bodies of Phong Nha-Ke Bang National Park - Determining of the quantitative distribution of freshwater crustaceans in the study basins, along with the variability of this group in spatial and climatic seasons - Proposal of measures for conservation and sustainable use of freshwater crustaceans resources in study area Contents 3.1 To identifying the species composition of freshwater crustacean of the Calanoida, Cyclopoida, Harpacticoida (Copepoda), Diplostraca (Cladocera), Podocopida (Ostracoda), Amphipoda, Isopoda Decapoda in the study area 3.2 To comparing the number of species and composition of species in different water bodies, especially in groundwater and underground waters in the cave 3.3.To determining the number of individuals of the studied species in the water bodies, and to consider the dynamics of their density in each type of water body in spatial and climatic seasons 3.4.To studying the relationship between the basic characteristics of water environment (to, pH, DO, salinity ) of the watershed and some biological parameters of freshwater crustaceans 3.5 To proposing solutions for preservation and sustainable usage of wetlands and freshwater crustaceans in the study area Chapter LITERATURE 1.1 Studies on freshwater crustacean in the world 1.1.1 Studies on the classification of freshwater crustacean groups 1.1.1.1 Freshwater Copepoda Müller (1776), Jurine (1820), Milne-Edwards (1840), Brady (1883) did have the studies on taxonomy for Freshwater Copepoda based on morphological characteristics Currently, in the world there are about 24,000 species of 2,400 genera and 210 families described Among them, there are about 2,800 species of fresh water inland (Boxshall and Halsey, 2004; Boxshall and Defaye, 2010) In Malaysia and Indonesia there were the research works of Douwe (1901, 1907), Daday (1906), in Java and Sumatra; Fernando (1978) on Copepoda fauna in Malaysia The research on the species in Cambodia was published from studies of Brehm (1951, 1954) The freshwater Copepoda of Thailand is investigated the most thoroughly from the studies of Boonsom (1984), Chullasorn et al (2008) Shen, et al (1979) described 206 species of Crustacea Copepoda of inland waters of China 1.1.1.2 Freshwater Cladocera Cladoceran was studied very early by Muller (1776, 1777, 1785) with a genus was first published It can be said that the study of Lilljeborg (1901) described and drew illustrated of 102 species with a system Cladocera taxa in the most successful at that time According to Martin and Davis, 2001, about 620 species were known as freshwater Cladocera ranked in four sets: Anomopoda (537 species), Ctenopoda (50 species), Haplopoda (one species) and Onychopoda (32 species) In Southeast Asian, the prominent works are of Richard (1891, 1895, 1896), Johnson (1956), which were realised in the island Java, Sumatra (Indonesia) In Malaysia, there were many studies realised by Johnson (1962, 1963, 1965, 1975), Idris (1983) In Thailand, there are studies by Boonsom (1984), Sanoamuang et al (2001), Maiphae et al (2005) Lastly, Chiang and Du (1979) have listed 136 species in 45 genera and 10 families in China 1.1.1.3 Freshwater Ostracoda Studies on Crustacea Ostracoda taxonomy had been started in 17771778 by Muller According to Martens et al (2008), there were 2,000 species of inland freshwater crustaceans in Ostracoda that have been recorded all over the world, most of them are free-living, only about 12 species of parasitic live, all belonging to the Podocopida According to Fernando (1982), there are 87 species of 26 genus recorded in Southeast Asia (Malaysia, Indonesia and the Philippines) Recently, Savatenalinton & Martens (2010) has a comprehensive research on the species composition of the Cypricercinae subspecies and describe six new species in this area 1.1.1.4 Freshwater Decapoda Since the mid-nineteenth century, many studies on freshwater shrimps and crabs have been conducted in countries in Europe and Asia According to De Grave et al (2008), there were about 2,500 species of Caridea shrimp belonging to 31 families, living in saltwater, brackish and freshwater Of these, about 655 are freshwater species There were 1,476 species of freshwater crabs known in the world distributed in all geographic regions of animals, including 1,306 pure freshwater species The two most abundant species were the Potamidae (505 species and 95 genera) and the Gecarcinucidae (344 species and 59 species), which were concentrated in Southeast Asia and South Asia (Cumberlidge et al (2009) According to Cumberlidge et al (2009), there were 10 countries with the largest number of freshwater crab species, of which are in Asia: China (224 species), Thailand (101 species), Malaysia (92 species), India (78 species), Sri Lanka (50 species) In other countries, although not yet fully registered, have recorded relatively large number of species, such as Indonesia (83 species), Philippines (42 species), Vietnam (40 species) 1.1.2 Studies on the habitat and distribution of ecological groups living in water bodie in karst 1.1.2.1 The water bodies of karst Based on topography, hydrology, and water environment, the limestone karst can be divided into three major groups, including: Lotic Environments, Lentic Environments, Underground Aquatic Environments 1.1.2.2 The division of groups of living organisms in the aquatic environment Today, in the study of cave fauna, Schiner-Racovitz's classification system of the species of underground organisms is widely accepted and used: "Trogloxenes" includes species get lost or attracted to the humidity or food sources of the cave, but they not always live in this environment and not reproduce here "Troglophiles" consist of living animals in the habitat underground, usually in shallow areas and caves; they also spawn here However, these species can also be found in terrestrial environments "Troglobites" consist of live animals in dark environments in deep soil or in caves They deeply transform the biological and ecological features that adapt to the environment Their entire life cycle start & end in this area and can not be found on the ground 1.1.3 Crustacean species composition in fresh water areas in karst In South East Asia, there many studies had been realised by Ng (1988, 1991, 1992, 1996); Ng & Naiyanetr (1993) Camacho (2005) described two new genera with two new species (Paraeobathynella vietnamensis, Sketinella trontelji.) in Vietnam Camacho et al (2011) described new genus with new species (Siambathynella laorsriae) in Thailand Victor & Fernando (1981) describes a new subfamily, a new species of Ostracoda from Batu, Malaysia In Copepoda, there are studies by Menzel (1926), Chappuis (1931); Bruno & Cottarelli (1999), Pesce & Apostolov (1985); Brancelj et al (2010) and Watiroyram et al (2012) According to Stoch & Galassi (2010), 4,775 species of invertebrates have been recorded in cave basins around the world, of which the number of crustaceans accounts for most known species, including 3,400 species, contributes up to 71.2% of total species In which the Copepoda group has about 1,000 species, the Ostracoda group has about 300 species, the Amphipoda group has about 950 species, the Bathynellacea group has about 200 species, and the Decapoda group has about 300 species According to Bracelj et al.(2013), in Southeast Asia, 102 species of freshwater crustaceans have been recorded in the groundwater aquifers: most of which are Decapoda (34 species), Copepoda (23 species), Isopoda (21 species), Amphipoda (13 species), Syncarida (5 species), Thermosbaenacea (3 species) and Ostracoda species According to statistics, the Philippines has the largest number of species with 34 species, Thailand (24 species), Indonesia (17 species), Malaysia (14 species), Vietnam (9 species), Cambodia (3 species), Laos (1 species) and Myanmar have not recorded any species in this crustacean group From 2013 to 2016, the reseachers continued to study and published 10 new crustacean species in Southeast Asia, including Vietnam: species of shrimp, crabs of Decapoda family (Do & Nguyen, 2014) Ng & Vidthayanon, 2013; Cai & Vidthayanon, 2016), species of Copepoda (Tran & Chang, 2014; Tran & Hołyńska, 2015, Boonyanusith et al., 2013; Watiroyram et al., 2015a, 2015b, 2016), a species of Thermosbaenacea family (Rogers & Sanoamuang L, 2016) 1.2 The study of freshwater crustacean in Vietnam 1.2.1 Reseach on taxonomy 1.2.1.1 Copepoda and Cladocera Prior to 1945, studies on the composition of the microcrustacean in Vietnam were mainly done by foreign authors From 1960 up to now, many studies had been realised by Dang Ngoc Thanh (1965, 1977, 1980); Dang Ngoc Thanh, Ho Thanh Hai (1991, 1992, 2001) In 2001, Dang Ngoc Thanh and Ho Thanh Hai described the classification of 50 species of Cladocera and 31 species of Copepoda Then there were studies by other authors such as Reid and Kay (1992), Hołyńska and Vu Sinh Nam (2000), Tran Duc Luong and Hołyńska (2015) Ho Thanh Hai, Tran Duc Luong (2007, 2008, 2009) Tran Duc Luong (2012) recorded 105 species of Copepoda belonging to 45 genera, 13 families, in oder of Calanoida, Cyclopoida and Harpacticoida Among them, Calanoida has 39 species, Cyclopoida oder has 29 species, Harpacticoida has 37 species in the inland waters of Vietnam 1.2.1.2 Ostracoda In Vietnam, the results of research on Ostracoda are very limited Only one species was recorded by Brehm (1952) in Hai Duong Dang Ngoc Thanh et al (1980) described the taxonomy of eight species of the Cypridae family in fresh water bodies of North Vietnam 1.2.1.3 Decapoda Freshwater crayfish (Decapoda) in Vietnam was studied by Edwardo from 1869 On freshwater shrimps, the works of Bouvier (1904, 1920, 1925), Sollaud (1914), recorded only five species in Vietnam including two species of Coutierella tonkinensis and Leander mani and three species of Atyidae: Caridina nilotica typica, C.weberi sumatrensis and C tonkiensis In the period from 1945 to 1975, in the North of Vietnam, there were studies by Dang Ngoc Thanh (1961, 1967), Dang Ngoc Thanh and Nguyen Huy Yet (1972) In 1975, Dang Ngoc Thanh presented a list of 27 species of shrimp and crab found in the waters of North Vietnam On freshwater shrimp, Dang Ngoc Thanh et al (1980) had documented and described eight new Caridina species; Then there were the authors N X Quynh, Peter, K L Ng and Liang X Q (2002) Dang Ngoc Thanh, Do Van Tu (2007, 2010) described six new species Atyidae for science in Vietnam In the South there were some studies which had been realised by Nguyen Van Xuan (1978, 1979, 1981, 1992, 2003, 2004, 2006, 2010, 2011) On freshwater crabs, Dang Ngoc Thanh and Tran Ngoc Lan (1992) described two new species of the genus Orientalia (Orientalia rubra, O tankiensis) from specimens collected in Nghe An and Thanh Hoa Ng (1996), Peter, KL Ng & Darren, CJ Yeo (2001), Tohru Naruse, N X, Quynh and Darren CJ Yeo (2011) continued to document and describe some other freshwater crab species in Vietnam Dang Ngoc Thanh and Ho Thanh Hai (2012) provided a list of 42 species of shrimps and 36 species of crabs recorded in Vietnam Do Van Tu et al (2015) described a new genus and species in Vinh Tan, Binh Thuan province (Binhthuanomon vinhtan); Do Van Tu, Nguyen Tong Cuong and Le Hung Anh (2016) described a new species of crab found in Huong Pagoda (Indochinamon Chuahuong); Hsu-Te Shih & Chao Huang (2016) described a new species of crab found in streams in Ha Lang District, Cao Bang Province (Tiwaripotamon pluviosum) According to data to date, Vietnam has recorded 43 species of shrimp and 41 species of freshwater crab 1.2.2 Research on freshwater crustaceans in the karst of Vietnam In 1967, Borutzky record seven species of Harpacticoida (Copepoda) in the Viguierellidae and Canthocamptidae families Subsequent studies of Camacho (2005), Brancelj (2005), Apostolov (2007) Tran Duc Luong et al (2011) recorded 39 species crustacean of Copepoda (18 species), Cladocera (12 species), Amphipoda and Decapoda in Trang An - Ninh Binh limestone area Tran Duc Luong and Cheon Young Chang (2012) announced two new species for science: Microthridion thanhi, Nitokra vietnamensis In the Phong Nha-Ke Bang karst area, some studies realised by Dang Ngoc Thanh and Ho Thanh Hai (2001) described two new species belonging to Calanoida in the underground river section of Phong Nha cave; Ho Thanh Hai et al (2003) provided a list of species of aquatic organisms (phytoplankton, zooplankton, zoobenthos and fishes) in Phong Nha cave, including 12 species of microcrustacea (Copepoda and Cladocera) found in the river in the Phong Nha cave Tran Duc Luong and Cheon Young Chang (2012) described a new Cyclopoidae in Thien Duong Cave With the group of shrimps and crabs (Decapoda), Ng (1996) recorded a new species and genus of crab (Nemoron nomas) in the Dark Cave (Phong Nha - Ke Bang) In 2014, Do Van Tu et al described a new species of crayfish (Macrobrachium phongnhaense) in the Va cave of Phong Nha-Ke Bang National Park 1.3 Studies on Phong Nha - Ke Bang karst This part presents an overview of geography, climate, weather and hydrology in the study area Types of water bodies in Phong Nha-Ke Bang karst Based on differences in hydrological morphology, hydrological and water environment, it is possible to divide the types of water bodies in karst of Phong Nha - Ke Bang range into main types such as: streams, rivers, small floodplains seasonal are located in low tide, reservoirs and underground cave systems Underground water in the cave Based on survey data, drawings of caves in the limestone mountains of Quang Binh by Tran Nghi et al (2003), Limbert (2012), conditions of hydrological and environmental Accordingly, the water bodies in the karst mountain cave in Quang Binh can be divided into four main types: Water flows in the interstitial; underground river in the cave; puddle of temporary water reservoir and underground lake in the cave CHAPTER II OBJECT, LOCATION, TIME AND METHODOLOGY 2.1 Objects and scope of research - Objects of study: Freshwater crustaceans of the Calanoidae, Cyclopoidae, Harpacticoida (Copepoda), Diplostraca (Cladocera), Podocopida (Ostracoda), Amphipoda, Isopoda, Thermosbaenacea, Bathynellacea, Decapoda and some water environment indicators rescue (T0, pH, DO, NH4+, NO3-, PO43-) - Scope of study: Study on species composition, distribution, species composition and the number (density) of freshwater crustacean in the karstic waters of Phong Nha - Ke Bang National Park 2.2 Study sites The study in an area of waters of Phong Nha-Ke Bang National Park, include: stream, reservoirs on the ground and underground water in cave Location of survey sites A total of 22 watersheds in the Phong Nha-Ke Bang were collected In particular, there are many water bodies surveyed in many places, Son River (3 sites), Chay River (3 sites), Khe Rinh (1 sites), Phu Nhieu (1 sites) Tan Hoa (1 sites), Cha noi (1 sites), Yen Hop (1 sites), Khe van(1 sites), Khe Dat (1 sites) Thien Duong (1 sites), Rao Con (1 sites) Phong Nha cave (4 sites), Son Doong cave (4 sites), Thien Duong cave (3 sites), Dark cave (2 sites), E cave (4 sites), 35 Cave (1 sites), Va Cave (2 sites), Tu Lan cave (3 sites) and Yen Hop cave (1 sites) 2.3 The study period - year: From 2013 to 2017 - Crustacean sample were inherited from the two surveys in 8/ 2011 and 4/2013 - During the implementation period, the thesis continues to survey and expand the study sites with study tours in April 2014, August 2014, September 2014, April 2015 and August 2015 with the support of Young 11 new species was identified to genus as Brancelia sp it is distributed in the cave 3.1.3 Freshwater Ostracoda Three species Ostracoda (3,2% of total species); these include: Pseudostrandesia calapanensis (family Cyprididae), Meridiescandona lucerna (Family Candonidae) and Notodromas sp (Notodromadidae family) Among them are Meridiescandona lucerna and Notodromas sp., the first recorded in the cave of Vietnam Two species of Meridiescandona genus and Notodromas genus are found only in the cave, while P albacanensis is widespread, often in mountainous waters 3.1.4 Bathynellacea Themosbaenacea The results of the study have identified two crustacean species that are only classified genus as: Theosbaena sp belonging to the Thermosbaenacea family and the Siambathynella sp species belonging to the Bathynellacea family, which are typical cave dwellings species These are the first records for the Vietnamese aquatic system 3.1.5 Amphipoda Isopoda One species of Amphipoda belongs to the Bogidiellidae family and one species of Isopoda belong to the Corallanidae family have been recorded At present, Vietnam has only recorded species of Amphipods and species of Isopoda 3.1.6 Decapoda According to the analysis, there were 16 species of Decapoda (17,2% of total species) of genus, families, including 10 species of shrimp (10.7%), species of crabs (6,5%) The most abundant species were the Palaemonidae with seven species, the Atyidae and the Potamidae each with three species, the two species of Parathelphusidae and the Varunidae with one species Based on the results, 11 species have been added to the Decapoda crustacean system in the karst areas of Quang Binh Of the 16 species of Decapoda identified in the study area, seven species (46.6% of total species) are now endemic to Vietnam, including: Caridina subnilotica, C.auticaudata, Macrobrachium phongnhaense, Indochinamon phongnha, Nemoron nomas, Villopotamon sp., Somanniathelphusa pax A new species of shrimp (Macrobrachium phongnhaense) was first record and described during the study So far, this species has only been found in caves in Phong Nha-Ke Bang National Park, as: Va Cave, 35 Cave, Tu Lan Cave and Son Doong Cave A species of Varuna litterata 12 was recorded at the survey sites of the Son River The study also recorded a species of Villopotamon sp The species name is also likely to be new to science 3.2 Distribution characteristics of species composition and a number species 3.2.1 Distribution by types of water bodies There were 49 species in underground water of the cave (52,7% of total species), 55 species in the stream (59% of total species), 52 species in the river (55,9% of total species) and 41 species in reservoirs (44,1% of total species) 3.2.1.1 The ground water in cave Based on the survey results, we have collected 49 species Crustacea, accounting for 52,7% of the total number of 10 Order, 19 families and 37 genus Of these, the most abundant is the Cyclopoida (Copepoda), with 20 species (21,5% of total species and 40,8% of total species in the cave), Harpacticoida (Copepoda) has species, Diplostraca (Cladocera) has species, Calanoida has species, Ostracoda has species, Decapoda has species, Thermosbaenacea, Bathynellacea, Amphipoda and Isopoda each have only one species For Ecologically, crustaceans in the cave could be grouped into two groups: the typical cave species group (Stygobites) and the unidentified cave species group(stygophiles) Typical cave species (stygobites): These include species that are only found in cave basins, usually deep in the cave There are 24 species of crustaceans (49% of cave species and 25.8% of total species), 21 genus, 12 families and oder In particular, the Cyclopoida (Copepoda) has the largest number of species with 10 species, the Calanoida and the Ostracoda each have three species, the Harpacticoida (Copepoda), the Decapoda has two species, the remaining one each Isopoda does not recognize any species in this group Species of the cave are unofficial (stygophiles): typical of this group is distributed both in caves and in other terrestrial waters in topography karst (streams, rivers, lakes) There are 25 species (51% of cave species and 26,9% of total species) in 21 genus, 11 families and oder In particular, the Cyclopoida (Copepoda) has the largest number of species with 10 species, the Diplostraca (Cladocera) and the Harpacticoida (Copepoda) each have species, the Calanoida has two species and the Isopoda has one species The Podocopida, Thermosbaenacea, Bathynellacea, Amphipoda and Decapoda have not recorded any species 13 Group of caves with typical cave species predominate: There are species of stygobites in the Va Cave, accounting for 100% of the stygobites species and no stygophiles species; Thien Duong has 14 stygobites species, accounting for 87,5% (2 species of stygophiles, accounting for 13,5%); Dark caves have 11 stygobites species, accounting for 78,6% (3 species of stygophiles, accounting for 21,4%); Cave 35 has 15 stygobites species, accounting for 78,9% (4 species of stygophiles, accounting for 21,1%); Son Doong cave has 15 stygobites species, accounting for 68,2% (7 species of stygophiles, accounting for 31,8%) Group of caves with dominant atypical species composition: Yen Hop cave, Tu Lan cave, Phong Nha hang E cave Phong Nha cave has 20 species of stygophiles, accounting for 95,2% of species (only species of stygobites, accounting for 4,7%); There are 14 species of stygophiles, accounting for 93,3% (1 species of stygobites, accounting for 7,7%); Tu Lan cave with 11 species of stygophiles, accounting for 78,6% (3 species of stygobites, accounting for 21,4%) and Yen Hop caves have species of stygophiles, accounting for 61,5% ( species of stygobites, 38,5%) 3.2.1.2 Water bodies on the ground 69 species of crustaceans (74,2% of total species) in 46 genera, 21 families and orders (Diplostraca, Calanoida, Cyclopoida, Harpacticoida, Isopoda and Decapoda) were recoded The other four are Podocopida, Thermosbaenacea, Bathynellacea, Amphipoda not recorded species Of these, the Diplostraca (Cladocera) has 25 species (26,9% of the total species and 36,2% of the total on the ground), Cyclopoidae (Copepoda) has 17 species, Decapoda has 14 species, Harpacticoida (Copepoda) has species, Calanoida has species, Isopoda has species Ecologically, it is possible to distinguish crustacean species in terrestrial waters as two major groups: the typical grouping of terrestrial surface water bodies (epigean species) (species can only be found in groundwater (rivers, streams, lakes) not found in cave basins) and unidentified cave species (stygophiles) Species of the cave are unofficial (stygophiles): they are distributed in both the surface waters and cave (described above 3.2.1.1) Typical species for on the ground (epigean species): There are 44 species belonging to 35 genera, 18 families and oder (Diplostraca, Calanoida, Cyclopoida, Harpacticoida and Decapoda), accounting for 63,7% of species on the ground and 47,3% of total species The Podocopidae, Thermosbaenacea, Bathynellacea, Amphipoda and Isopoda have not recorded any species 14 Distribution according to types of terrestrial waters characteristic of the study area include rivers, streams and reservoirs Crustacean species were recorded in streams with 55 species (59,1% of total species), rivers with 52 species (55,9%) and lakes with 41 species (44,1%) The Diplostraces have 22 species in rivers and streams, 19 species in reservoirs Cyclopoids have 13 species in streams, 12 species in rivers and species in reservoirs; The Decapoda has river species, 13 species in the stream and species in the reservoir The Harpacticoida have species in the river, species in the stream and reservoir; Calanoida have species in the river species in the stream and species in the reservoir, the Isopoda have only one species in the river 3.2.2 Distribution between planktonic crustaceans and benthic crustaceans The research has identified 65 species of planktonic crustaceans (accounting for 69,9% of total species) and 39 species of benthic crustaceans (accounting for 41,9% of total species) Crustaceans live in the upper layer (planktonic crustaceans): Cycopoida have 27 species (29% of total species), Diplostraca have 25 species (26,9%), Calanoida have species (8,6%), Harpacticoida and Podocopia have only to species The Thermosbaenacea, Bathynellacea, Amphipoda, Isopoda and Decapoda have not recorded species Crustaceans living in the bottom layer (benthic crustacea): The Species composition is dominant in this group belongs to the Decapoda with 16 species (17,2% of total species), Harpacticoida have species (9,6%), Cylopoida have species (6,4%), Podocopia has species (3,2%), the other four oder (Thermosbaenacea, Bathynellacea, Amphipoda and Isopoda) each have only species (1%) For the Diplostraca with the dominant species at the surface level (25 species), however, no species was recorded at the bottom 3.2.3 Seasonal distribution There are 80 species of crustaceans in the dry season (86,0% of the total species) and 70 species in the rainy season (75,2% of the total species) In both seasons, there are representatives of freshwater crustacean in the karst The two most abundant oder are the Diplostraca (Cladocera) (21 species in dry season and 20 species in rainy season) and Cyclopoida (Copepoda) (22 species in dry season and 17 species in rainy season); The Decapoda with 15 species in dry season and 13 species in 15 rainy season At least one species of Isopoda is present in the dry season and no species appear in the rainy season 3.3 Distribution of density of the Crustacea 3.3.1 Crustaceans living in the upper (Planktonic Crustacea) The density of Planktonic crustaceans from 22 to 2131 individuals /m3, the average values ranged from 31,5 to 1440 individuals/m3, with the appearance of the Diplostraca (Cladocera), Calanoidae, Cyclopoida, Harpacticoida (Copeopoda), and Podocopida (Ostracoda), in which Cyclopoida and Diplostracia dominate Surface water bodies and cave basins also show differences in density and structure of Planktonic crustacean species For the underground water bodie in the cave: The average density from 46,3 to 152,0 individuals /m3, with the density advantage in most of the survey sites belonged to the Cyclopoida (39,5 – 79,4%) Total density of Diplostraces is lower (from 8,0 to 38,2%) The highest average density at Va cave was 152,0 ± 35 individuals /m3 and lowest in Phong Nha cave with 46,3 ± individuals /m3 For watershed on the ground: the average Planktonic crustacean density ranges from 74,7 to 1150,2 individuals/m3 with the density of species in the Diplostraca and Cyclopoida, from 25,2 – 65,8% of total densities in Diplostraca and 23,9 – 66,8% in Cyclopoida Density of planktonic crustacean groups in reservoirs: Dong Suon lake averaged from 380,7 to 879,0 individuals/m3 and Khe Ngang lake averages from 962,3 to 1440,0 individuals/m3 In the species composition, the predominant density of species groups is evident The Cyclopoidae, Diplostraca and Calanoida grow in numbers in standing or slow-moving water For streams, the average planktonic crustaceans ranged from 74,7 to 154,0 individuals/m3 In the composition of the species composition, the Diplostraca and the Cyclopoida have advantages For the Son and Chay River basins, the variability ranged from 175,2 to 327,3 individuals/m3 In terms of species composition, the Diplostraces and Cyclopoids still dominate (accounting for 25,2-66,8% of the population) These are species adapted to the flowing water environment Variation of plaktonic crustacean densities in season: For surveys (3 rainy season and rainy season), the variability of planktonic crustaceans in the water bodies was clearly shown: almost the dry season 16 density was higher than with the rainy season depending on the different water surface conditions For River, tream basins on the ground: The density of planktonic crustaceans in the dry season was higher than that of the rainy season with average density of 89,0 - 371,1 individuals /m3 in the dry season and (from 64,5 – 233,7 individuals / m3 in the rainy season) For underground water basins in cave: In underground streams with continuous flow from surface water bodies (E cave, Tu Lan cave): in the dry season, the density from 133,0 to 145,5 individuals/m3 is higher than that in the dry season With the rainy season, the average is from 81,8 to 90,0 individuals/m3 In the underground streams from the cave (Phong Nha cave, Dark cave, Son Doong cave, Thien Duong cave), the difference between the two seasons is negligible with the dry season (from 51,0 to 68,8 individuals/ m3) and rainy season (from 43,0 to 64,3 individuals /m3) In the small pond or lake in the cave (35 cave, Yen Hop cave and Va cave), the planktonic crustaceans in the rainy season (from 52,0 to 196,0 individuals/m3) higher than that in the dry season (from 42,0 to 130,0 individuals /m3) 3.3.2 The Benthic crustacean Based on the results of the reseach, the density of benthic crustacean from to 70 individuals /m2 in water bodies, with an average value of 20,2 - 40,9 individuals /m2 In which Cyclopoida, Harpacticoida (Copeopoda) completely dominate (accounting for 31,5 - 100,0% density) Through analysis, only three oder of Cyclopoida, Harpacticoida (Copeopoda), Podocopida (Ostracoda) are present in the samples both in the upper and lower layers The density of benthic crustaceans was 29,1 ± 4,9 individuals /m2 in suface water bodies and 32,9 ± 5,7 individuals /m2 in cave basins Composition of benthic crustacean in terrestrial surface water bodies consists of orders: Cyclopoida, Harpacticoida and Decapoda However, benthic crustacean in the basin of the cave have the appearance of species belonging to the Podocopidae, Thermosbaenacea, Amphipoda, which are typical species in the cave In water bodie on the ground, the diverticulata was 28,9 ± 6,2 individuals / m2, the streams were 27,5 ± 4,9 individuals/m2 and the reservoir was 31,7 ± 2,9 individuals/m2 The variability of benthic crustaceans tends to increase with the flow direction in the water bodies 17 The seasonal variation benthic crustacea of density: The seasonal variation in the terrestrial waters is more evident than groundwater bodies in cave The groundwater bodies in cave, seasonal fluctuations are not large, In Va cave, 35 cave, Heaven cave in rainy season is higher density than dry season, however, the difference is not large E cave, water bodie rive stream in the cave with frequent flowing water However, cave E is a creek in the cave with frequent flow of water and fluctuations in the flow between the rainy season and the dry season, therefore the dry season density (26,9 ± 11,8 individuals/m2) was higher than the rainy season (15,0 ± individuals/m2) For water bodies such as rivers and streams on the ground, the density of benthic crustaceans in dry season (31,3 ± individuals/ m2) was higher than that of rainy season (25,5 ± individuals /m2) The variation in density in the reservoir also had the difference in average dry season density of 35,9 ± 5,8 individuals/m2 higher than the rainy season with a density of 29,6 ± 3,9 individuals /m2 3.4 Biodiversity of freshwater crustaceans 3.4.1 The Planktonic Crustacean 3.4.1.1 The Margalef index (d) The Margalef index (d) of Planktonic crustacea ranges from 0,80 to 2,51 In particular, the lowest in the streams (1,47 ± 0,21), the cave basins (1,68 ± 0,25); in the reservoir (1,83 ± 0,11) and highest in the river (1,91 ± 0,21) The Margalef index ranges from 0,80 to 2,29 for the cave Some caves with high abundance index such as Tu Lan cave (d average 1,94 ± 0,10), Dark cave (1,84 ± 0,08), Phong Nha cave (1,83 ± 0,15 ) and E cave (1,77 ± 0,24) because they have regular water exchange with open water bodies The remaining water bodies have lower margalef such as cave Va (1,21 ± 0,16), Thien Duong cave (1,33 ± 0,26) and Yen Hop cave (1,64 ± 0,03) As these deep in the cave, the level of connection of water sources with water bodies on the ground is limited For water bodies on the ground: The species richness index in the two reservoirs was 1,83 ± 0,11, the difference in abundance of freshwater crustacean was not significant, d index from 1,39 to 2,19 For the streams, the d index was low (1,47 ± 0,21) and fluctuated considerably, from 1,12 to 1,95 The streams are located in the core zone of Phong Nha - Ke Bang National Park, such as Thien Duong (1,72 ± 0,09), Khe Dat (1,69 ± 0,21), Rao Con (1,45 ± 0,06) higher the streams in the buffer zone, Phu Nhieu stream (1,30 ± 0,23), Cha Noi stream (1,29 ± 0,12), Yen Hop stream (1,39 18 ± 0,06) and other streams near the residential area, Khe Rinh (1,46 ± 0,12), Tan Hoa stream (1,25 ± 0,07) Variable margalef index of freshwater crustaceans in seasonal In river, stream on the ground, richness index of Planktonic crustacean in dry season (average 2,04 ± 0,11 in rivers and 1,80 ± 0,19 in streams ) was higher than the rainy season (1,54 ± 0,14 in the river and 1,38 ± 0,15 in the stream) For underground water in cave, the rainy season (1,69 ± 0,22) was higher than the dry season (1,65 ± 0,24) In reservoirs, the difference richness index between the two seasons was similar, with an average of 1,83 ± 0,07 in the dry season and 1,84 ± 0,09 in the rainy season 3.4.1.2 Shannon-Weiner diversity index(H’) The diversity index of the freshwater Planktonic crustaceans ranges from 1.18 to 2.80 In particular, the lowest in the streams (1,63 ± 0,24), the cave (1,95 ± 0,01) and the highest in the lake (2,09 ± 0,12) and in the river (2,10 ± 0,25) Aquifers in the cave, the species diversity index H' from 1,32 to 2,31, the average value between the water areas ranged from 1,79 to 2,06 Results of variation in freshwater crustacean diversity indexes in seasonal watersheds: In river basins, stream on the ground, the abundance of crustaceans in the rainy season (2,04 ± 0,22 in the river and 1,54 ± 0,16 in the stream) were lower than those in the dry season (2,21 ± 0,13 in the river and 1,71 ± 0,16 in the stream) (with p> 0.05) For underground water in the cave, the difference in seasonal species diversity is negligible: H' average was 1,96 in the rainy season, higher in the dry season (1,92 ± 0,09 ) In the seasonal reservoir of the H 'diversity index in the rainy season (2,11 ± 0,09) tended to be higher than in the dry season (2,04 ± 0,10) 3.4.2 The benthic crustacean group 3.4.2.1 Margalef index (d) The richness index of freshwater benthic crustaceans ranged from 0,54 to 2,07 In particular, the highest abundance was found in the river (1,52 ± 0,22), reservoir (1,27 ± 0,14), cave basins (1,11 ± 0,16) ) and streams (1,13 ± 0,22) Seasonal survey: In rivers, the rainy season (1,67 ± 0,22) was higher than the dry season (0,41 ± 0,08) At the same time, the difference in species richness between dry and rainy seasons is not significant for other: in streams (1,07 ± 0,21 in dry season and 1,10 ± 0,11 in rainy season); lakes (1,12 ± 0,10 in the dry season and 1,32 ± 0,05 in 19 rainy season) and in the basin of the cave (1,12 ± 0,19 in the dry season and 1,07 ± 0,17 in rainy season) (with p> 0.05) 3.4.2.2 Shannon-Weiner diversity index(H’) Based on the results, the species diversity index (H ') ranged from 0,76 to 2,27 The survey sites in the streams with the lowest diversity index H ', the average was 1,31 ± 0,13, the basin in the cave (1,40 ± 0,19), the reservoir water (1,42 ± 0,11), Song Son and Chay River are the highest H', Son River (1,81 ± 0,24) and Chay River (1.57 ± 0.23) Seasonal survey: rainy season is usually higher than dry season, average 1,79 ± 0,25 in rainy season and 1,62 ± 0,10 in dry season Similar results for each type of water body are in lakes: (1,45 ± 0,09 in rainy season and 1,37 ± 0,07 in dry season); (1,30 ± 0,08 and 1,27 ± 0,06) in the stream and (1,41 ± 0,06 and 1,33 ± 0,15) in the basin of the cave These indicators show the relative stability of the habitat and aquatic communities at the bottom of the water bodies 3.5 Correlation between freshwater crustaceans and environmental factors 3.5.1 Water quality in the karst areas of Quang Binh Province Based on the analysis of indicators of physical and chemical factors water environment in Phong Nha - Ke Bang karstic waters, we can comment on the current state of the water environment Compared with the standard of surface water bodies environment used for daily life and protection of aquatic life; most of the surveyed indicators are within the allowable limits (QCVN 08: 2015, QCVN 09: 2015) There are some differences in the physical and chemical indicators between surface water bodies on the ground and cave basins The difference in this water environment is mainly due to the hydrological regime, the basin structure, the water body type, especially the sunlight mode (underground water in caves without sunlight) This shows that although there are certain connections between the inner and outer rivers in the rainy season, the habitat between the basin in the cave and the outer surface is completely different Nowadays, with the development of tourism and other activities of people here, more or less impact on the natural ecological environment in the Phong Nha-Ke Bang National Park, so there must be solutions To improve the people's consciousness in order to protect and maintain the current status of the water environment in these water basins, which is 20 also the basis for the sustainable development, harmony between environmental protection and economic development 3.5.2 Correlation between environmental factors and biological parameters of crustaceans For surface water bodies such as rivers, streams and lakes Physical factors such as temperature and light have a very weak correlation with the species index, density and diversity index Indicators such as pH, Stiffness and salinity are weakly correlated with the species, density of the freshwater crutacean The DO and NO3-content indexes have a mean correlation (0,12-0,35) and ammonium content (0,35-0,56), phosphorus (0,35-0,61) have a tight correlation Nutritional factors from ammonium salts (NO3-) and phosphates (PO43- ) have variable variability associated with changes in species index, density and diversity index As the nutrient content increases, the number of species, density and diversity tend to increase This result reflects the characteristics, in accordance with the results of the analysis of physical and chemical factors in the watershed here: poor nutrition For groundwater bodies in caves, water environment factors such as temperature, hardness, and pH have a weak correlation with species indexes, density and diversity indexes The chemical indices such as DO, NH4 +, NO3-, PO43- in groundwater bodies are positively correlated and fluctuate relatively closely with species variation (coefficient of correlation r from 0,58 – 0,73) Crustal density is strongly correlated with NO3- (0,81); PO43-, NH4+, DO have average correlation For the Margalef index (d) and the diversity index (H ') the correlation coefficient for water environment factors such as (DO, NH4+, NO3-, PO43-) ranged from medium to low (0,32-0,59) 3.6 Solutions for conservation and sustainable use of freshwater crustacean resources in the study area 3.6.1 Main threats to the aquatic ecosystem and crustacean communities in Phong Nha - Ke Bang At present, the decline of natural resources in general is taking place in many localities in the country With the impact of natural disasters and other human-induced activities, crustacean resources in Phong Nha-Ke Bang National Park are also seriously threatened, such as the effects of weather, due to climate change; Deforestation of watersheds, overexploitation of fishery resources, especially tourism activities have been strongly developed in Phong Nha - Ke Bang 21 3.6.2 Suggested solutions for conservation of ecosystem biodiversity and crustacean communities in caves in Phong Nha - Ke Bang Based on the results of the study and field surveys, five groups of solutions proposed to conserve and develop the biodiversity in general and the crustacean group in particular include: sustainable tourism development planning, Raise awareness on biodiversity conservation education; Build awareness of environmental protection for local communities and visitors; Develop scientific research projects and biodiversity monitoring; Control of invasive alien species CONCLUSION AND RECOMMENDATION I CONCLUSION Based on the results, 93 crustacean species have been identified in the karstic areas of Phong Nha-Ke Bang National Park, belonging to 61 genera, 27 families and 10 oders Among them, one species (Halicyclops songsonensis Tran, Le & Ho) has been new record to science For the first time, two oder of fresh water crustacean (Thermosbaenacea and Bathynellacea), families (Notodromadidae, Candonidae, Halosbaenidae, Parabathynellidae, Bogidiellidae), 11 genus (Acanthocyclops, Nitocrella, Brancelia, Bryocyclops, Graeteriella, Rybocyclops, Notodromas, Meridiescandona, Theosbaena, Siambathynella, Bogidiella) In addition, 14 species and unidentified species have many characteristics that differ from species currently known These may be new to science, but additional specimens and information are needed to ensure accuracy when describing species Identification of species distribution and composition of species by water type, water layer and season Of which, streams have the highest number of species (55 species, accounting for 59,1% of total species), rivers (52 species, accounting for 55.9%), underground water in caves (49 species, accounting for 53,7% % and reservoir (41 species, accounting for 44,1%) Surface of the water body has more species than the bottom (65 and 39 species respectively); Dry season recorded higher species than rainy season (80 species compared to 70 species) According to the distribution characteristics of freshwater crustaceans, the stygobites (24 species, accounting for 25,8%), stygophiles (25 species, accounting for 26,9%) and epigean species (44 species, accounting for 47,3%) Crustacean densities in the karstic areas of Phong Nha-Ke Bang National Park ranged from to 70 individuals/m2 in the benthic crustacean and in the plankthic crustacean from 22 to 2.131 22 individuals/m3 Characteristics of freshwater crustaceans are described by the type of surface water bodies (rivers, streams, reservoirs) and underground bodies in caves (underground rivers, puddles, underground siphon pools) In surface water bodies, the reservoirs have the highest density of crustaceans (from 380,7 to 1440 individuals/m3) For cave basins, the highest density of siphon reservoirs and the lowest seasonal lowland floods were from 46,3 to 63,3 individuals/m3) The Margalef diversity index (d) and the species diversity index (H') in crustacean waters of Phong Nha - Ke Bang National Park are average, with the plankthic crustacean ranging from 0,80 to 2,51 (d index) and 1,18 to 2,80 (H ') and for the benthic crustacean ranged from 0,54 to 2,07 (d) and 0.76 to 2,27 (H') The results show that the abundance index and diversity index in the underground water is equal to or higher than that of the stream The water environment in the karst areas of Phong Nha-Ke Bang National Park includes both surface water and underground water in the cave are good condition; Physical and chemical indicators are within the permitted limits as compared to Vietnamese standards In most of the karstic areas of Phong Nha-Ke Bang National Park, the characteristics of freshwater crustaceans (number of species, density, d, H') are weakly correlated with physical indices Temperature, pH, stiffness, while they are positively correlated, varies from medium to tight with chemical indices such as DO, ammonium salt, nitrate, phosphate in water It has been determined that the rapid development of tourism in Phong Nha - Ke Bang National Park is a major factor affecting the ecosystem of the cave and the crustacean Based on that, five solutions have been proposed to preserve cave ecosystem and endemic crustacean species in Phong Nha - Ke Bang National Park II RECOMMENDATION In the coming time, it is necessary to study and collecte more specimens, for unidentified crustaceans in the cave (14 species) and especially for the species with description In addition, studies on other aquatic organisms (molluscs, fish, etc.) should be extended to serve the management of biodiversity conservation in the cave basin Based on the research results of this thesis, light is an environmental factor that determines the ecological characteristics of the crustaceans living in caves only Therefore, it is necessary to orient the biological experiment to determine the intensity of light affecting the 23 behavior and habitat of this ecological group.The results of the study will be the basis for the identification of environmental indicator organisms in the cave aquifer THE NEW CONTRIBUTION OF THE THESIS - Based on the results of this thesis, we have provided the most complete data to date on the composition of freshwater crustacean in Phong Nha-Ke Bang National Park, including 93 species, 61 genus, 27 families in 10 oder - One species (Halicyclops songsonensis Tran, Le & Ho) has been newly recorded to science; provide data and specimens to describe and announce three new species for science: Mesocyclops sondoongensis, Nannodiaptomus haii and Macrobrachium phongnhaense The results of the study were supplemented with two oder of freshwater crustacean (Thermosbaenacea and Bathynellacea), five families (Notodromadidae, Candonidae, Halosbaenidae, Parabathynellidae, Bogidiellidae) and 11 species (Acanthocyclops, Nitocrella, Brancelia, Bryocyclops, Graeteriella, Rybocyclops, Notodromas, Meridiescandona, Theosbaena, Siambathynella, Bogidiella) Most of these taxa are official life representatives in cave basins - Distribution characteristics of species composition and density of freshwater crustacean communities in Phong Nha-Ke Bang karstic waters were analyzed and evaluated in detail by type of water bodies (49 species in basins, 55 species in streams, 52 species in rivers, 41 species in reservoirs), (65 species Planktonic crustacea and 39 species benthic crustacean) and seasonal climate (80 species in the dry season and 70 species in the rainy season) Classification of species groups based on ecological characteristics, distribution according to specific types of watersheds in the study area (24 the stygobites species, 25 stygophiles species and 44 epigean species ) These are new data of scientific and practical value in the research and management of biodiversity and conservation of limestone species in Phong Nha - Ke Bang - Determining the species diversity of freshwater crustacean species in Phong Nha-Ke Bang karstic areas, including rivers, streams, reservoirs and cave basins The results show that the abundance index and diversity index in the groundwater bodies in caves is equal to or higher than that of the stream 24 - Initially, the correlation between freshwater crustaceans and some basic water environment factors was investigated to investigate the adaptability of crustacean communities to the water bodies in karst The available data will be the basis for studies assessing the impact of environmental factors on karst aquatic communities as well as the ability to direct the biology of freshwater crustaceans for work on water environment 25 LIST OF WORKS HAS BEEN PUBLICATON Tran Duc Luong, Le Danh Minh, Ho Thanh Hai A new species of the genus Halicyclops (Copepoda, Cyclopoida, Cyclopidae)from freshwater in central Viet Nam, Journal of Biology, 2016, 38 (4), page 449 - 457 Tran Duc Luong, Ho Thanh Hai, Le Hung Anh, Le Danh Minh Biodiversity of cave – dwelling microcrustacea in Phong Nha – Ke Bang national park, Quang Binh Province, The 6-th National Scientific conference on Ecology and Biologycal resources, 2015, page 665 – 670 Nguyen Tong Cuong, Do Van Tu, Le Danh Minh, Dang Van Dong, Species composition of freshwate shrimp and crab in Phong Nha – Ke Bang national park, Quang Binh Province, The 6-th National Scientific conference on Ecology and Biologycal resources, 2015, page 493 - 497 Tran Duc Luong, Ho Thanh Hai, Le Danh Minh A new record of the genus Limnocletodes Borutzky, 1926 (Cletodidae: Harpacticoida) with redescription of three species from Viet Nam, Journal of Biology, 2013, 35 (1), page – 17 ... Phong Nha- Ke Bang National Park" Objective - Having sufficient data on the leading component of freshwater crustaceans in waters bodies of Phong Nha- Ke Bang National Park - Determining of the quantitative... crustacean in the karstic waters of Phong Nha - Ke Bang National Park 2.2 Study sites The study in an area of waters of Phong Nha- Ke Bang National Park, include: stream, reservoirs on the ground and. .. described a new species of crayfish (Macrobrachium phongnhaense) in the Va cave of Phong Nha- Ke Bang National Park 1.3 Studies on Phong Nha - Ke Bang karst This part presents an overview of geography,