Studies on Wetland Biodiversity in China - Chinese Academy of ...

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Studies on Wetland Biodiversity in China ZHAO Kuiyi 1, HE Shunping 2& LI Wei 3 1

Northeast Institute of Geography and Agricultural, CAS, Changchun,130012 Institute of Hydrobiology, CAS,Wuhan,430072 3 Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, CAS, Wuhan, 430074 2

This paper briefly summarizes the history of wetland research, the evolvement of wetland science, and their impacts on the understanding of wetland biodiversity in China. A marsh is the key type and basic component of a wetland. Defining the marsh and wetland plants is the basis for understanding the wetland and its biodiversity. The comprehensive multiple factorial classification principles and the multiple developmental models of the wetland are two innovative feats achieved by Chinese scientists, and their application has further promoted ecological research. The CAS Wetland Research Center has made historic contributions to the study of the wetland and its biodiversity in China. Also, the paper discusses several important tasks of wetland and biodiversity research. Key words: biodiversity; wetland; study; China

Forty years ago, a group of ambitious new graduates stepped onto “the Great Northern Wilderness” of northeast China to conduct research into wetlands. Although green vegetations extend thousands of miles on this land, very few people had ever lived here. For decades, these young researchers walked through the marshes and swamps, enduring mosquito bites and facing the danger of various hidden traps, and made very careful examinations to collect accurate data. Their work paid off, opening the gate to a knowledge kingdom of wetland studies in China.

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Ecosystem Protection

Wetland plant communities dominated by Phragmites australis in Panjin in northeast China (photo by Zhao Kuiyi)

W

etland biodiversity refers to an ecosphere comprising wetland organisms, its environmental factors and associated biological processes. It involves millions of animals, plants, microbes, their genomes and the ecosystem formed by the interactions between these organisms and the wetland environment. As the wetland ecosphere contains the most abundant biodiversity with the highest ecological value, it is often called the “cradle of life.” In the past several decades, the wetland and biodiversity research in China has gone through several revolutionary changes. In April 1960, China’s first wetland research symposium was sponsored by the CAS Changchun Institute of Geography (which became the Northeast Institute of Geography and Agroecology, or NEIGAE in 2002) and the Northeast Normal University, with Prof. K. E. Ivanov, a distinguished wetland scientist from Russia, giving an invited speech at the meeting (Huang, 2003). It was followed by several pioneering efforts of Chinese researchers, including the publication of the first edition of

Mires of China (Zhao, 1999), the first volume of Wetland Vegetation of China (Editorial Committee, 1999), the first textbook An Introduction to Mire Science (Liu et al., 2006), the first Mire Maps of China (Wang, 1999), China’s first wetland herbarium, and China’s first wetland and marsh database. These achievements laid a cornerstone for the formation of the theories and disciplinary system of wetland science. Since then, wetland science and related biodiversity research have made progresses through the persistent exploration and innovation of Chinese researchers. The importance of these studies is increasingly recognized by the academia, the public and government officials at various levels. T h e y e a r 2 0 1 0 i s t h e “ I n t e r n a t i o n a l Ye a r o f Biodiversity.” Many countries in the world including China have set up their own national committees for International Biodiversity Year. The organization of the Chinese committee reflects the central government’s concern over biodiversity protection.

Retrospect and Current Status 1. Establishment of mire science 1.1 Exploration stage of mire research The mire is the main type and basic component of wetlands. It was called the “damp and low-lying land” in ancient China (Ji, 1995). However, the study of wetland did

not become an independent research discipline in China until the CAS Changchun Institute of Geography was founded in 1958 in northeast China, where wetland resources are most abundant. One of the Institute’s major tasks was to launch a nationwide survey of wetlands. The key theoretical issues in mire research are the

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definition, classification and development study of the wetland. In the beginning, Chinese researchers followed the “phylogeny group classification” system established by Russian scientists. The system argues that all wetlands should be classified by the various stages of a uniform development process, i.e., each wetland evolves from a low order to a high order or from a juvenile to senile stage. The different stages of maturity were used as the criteria for wetland classification. According to this theory, the Sanjiang Plain’s herbaceous wetland was considered in a low order or juvenile stage, which would gradually develop into a meso-position and high bog. However, based on the national survey, Chinese researchers did not find any successive evolving process from the herbaceous (low-order) wetland to a bryophyte (high-order) one from Northeast China’s Sanjiang and Songliao plains to the Yangtze Plain in the east and the Tibetan Plateau in the southwest. The Russian theory was questioned in the 1970s (Huang, 1988; Niu & Zhang, 1988). In the 1980s, Zhao Kuiyi went to the Nordic countries including Finland, Sweden and Norway where wetlands are abundant, and then to Canada and the United States for scientific investigations. He found that this theory is only tenable for frigid-temperate zones, such as the taiga coniferous forest regions, and it was only valid in the peat bog regions well-developed in Northern Europe. 1.2 Special projects CAS attaches special importance to wetland research. In 1992, the Academy launched a systematic survey and classification study into China’s lakes and wetlands as a special project of its basic research program on lakes and wetlands. The research involved a supplemental survey of China’s wetlands and the writing of Mires of China, which were undertaken by the Wetland Laboratory of the

Changchun Institute of Geography. For the survey, CAS researchers covered a vast area from northeast China’s Sanjiang Plain to the Tibetan Plateau, and from the southeast coastal areas to the northwest border regions. Thanks to the three-year survey, a one-million-character works Mires of China was published in 1999. It was a summary of the findings of four-decade field investigations by researchers from the Northeast Institute of Geography, as well as an introduction to the basic theories of wetland study and the evolutionary scenario of wetlands in a systematic and all-round way, laying a foundation for the booming development of wetland research in China. In Mires of China, a wetland is defined as a special natural complex with three interconnected and interconstrained properties: earth’s surface perennially inundated by stagnant water or water-soaked soil, the growth of wetland and mire plants, and peat accumulation or soil with obvious gley horizon. The standing water level of a wetland is usually about 2m deep. When water exceeds that depth, the land loses the three properties and should no longer be considered as a wetland. Instead, it forms a deep water body such as a lake or pond. The researchers also proposed, for the first time in China, the definition of wetland plants: a plant that grows and completes its life cycle in stagnant water or extremely wet soil. Further classification divides wetland plants into five groups: floating plants, floating-leaf plants, submerged plants, emerged plants and hygrophytes (Zhao, 2006). The clear definition of wetland plants is very important for determining the wetland area. For instance, forest wetlands are often distinguished by the presence of “indicator plant species” or “characteristic plant species.” The above two definitions can be used as the criteria for

Wetland plant communities dominated by Suaeda heteroptera in Panjin in northeast China (photo by Zhao Kuiyi)


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Wetland plant communities dominated by Nelumbo nucifera in the Sanjiang Plain Poyang Lake in northeast China (photo by Zhao Kuiyi)

differentiating various types of complex wetlands, and are fundamental for the study into wetland biodiversity. To depict the characteristics of China’s wetlands, CAS researchers proposed “the principles and systems for comprehensive classification of wetlands and the properties of basic wetland types”, as well as their “distribution and development patterns”. They stressed that the complexity of different types of wetlands indicates that its development in different places should follow different models (Huang, 1988). Using different grading criteria, the CAS researchers established a more comprehensive classification system for wetlands in China. It represented a breakthrough in the field with significant influences on the nation’s ecological studies. And the construction of a “wetland reserve network” was first proposed in essays like the Structure and Function of Wetland Ecosystem and the Utilization and Protection of Wetland Resources. Over the past 40 years, CAS researchers have collected more than 10,000 plant samples from wetlands all over the country. Now the specimens are preserved in the Chinese Wetland Herbarium, which is located at NEIGAE. A Primary Catalog of Wetland Plants in China was also published in 1995 (Zhao, Zheng, & Yi, 1995; Wang, Sun, & Yi, 1995). All these work epitomizes the biodiversity fecundity and biomass productivity of China’s wetland resources. The publication of Mires of China was highly appraised by wetland researchers and administrators across the country, saying the book has filled a gap for China’s wetlands research and laid a solid foundation for biodiversity studies. They believed that it had enriched

China’s ecological knowledge base and would play a significant role in promoting the scientific development and utilization of wetland resources.

2. Booming wetland research in China 2.1 Wetland research centers under CAS The Chinese government has attached great importance to the study and protection of wetlands. To deal with the challenges of global resources, population and environment, China joined the Convention on Wetlands of International Importance, especially as Waterfowl Habitat in 1992. In China’s Agenda 21, the preservation and proper utilization of wetland resources are among the top priorities. On June 27, 2004, the General Office of the State Council issued the Circular on Further Strengthening the Management of Wetland Protection, the first official document for the protection and management of domestic wetlands in China since 1949. The government’s move has spearheaded wetland protection across the nation, and corresponding research activities in this field have sprouted out rapidly. The CAS Wetland Research Center was inaugurated in Changchun in northeast China’s Jilin Province on August 7, 1995. Its opening ceremony was attended by Prof. CHEN Yiyu, then CAS vice president and the director of the Center, Deputy Governor of Jilin Province LIU Shuying, and other government officials and leading scientists from 13 CAS institutes, including the Changchun Institute of Geography, Nanjing Institute of Geography and Limnology, Wuhan Institute of Hydrobiology and Wuhan Institute of Botany.


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A Nymphoides peltata community in the Heilongjiang Reaches, northeast China (photo by Zhao Kuiyi)

While conducting large-scale surveys and research projects on China’s wetlands, and hosting seminars and workshops, the Center has trained many leading researchers in the field. It also assisted the State Forestry Administration to work out China Action Plan for Wetland Protection. In addition, the Center has made recommendations to decisionmakers on ways of properly protecting and utilizing wetland resources based on the real situation in China. An enormous amount of consultative work has been accomplished with significant outcomes. The Center’s work has impressed the wetland research community in China. Soon, “the Center for Wetland Resources and Environmental Studies for Universities” was sponsored by the Ministry of Education and jointly set up by the Northeast Normal University and East China Normal University. Later, several other centers for wetland research were built up, and the CAS Wetland Research Center played a leading role in the booming wetland research in China. 2.2 National surveys of wetland resources The government decided in the early 1990s to survey the wetlands across the country. In June 1995, the State Forestry Administration organized China’s first workshop on wetland survey technology in Yantai, east China’s Shandong Province. The CAS Changchun Institute of Geography was chosen by the Administration and CAS to give lectures at the workshop. In order to prepare teaching materials, the Institute set up a special panel of experts from various CAS institutes, including LIU Xingtu, ZHAO Kuiyi, LU Xianguo, JI Zhongchun, WANG Huaqun, LI Wencheng, FAN Chengxin, CHANG Jianbo and WANG Ziqing. After the edit of Zhao Kuiyi, the Instructions for


Wetland Survey in China was finalized and taught by the experts to trainees, who were officials and scholars from all over the country. Following the workshop, the State Forestry Administration initiated a seven-year-long nationwide survey. The survey involved tens of thousands of professionals and was fruitful in three major aspects. First of all, the workers thoroughly investigated all wetlands that are larger than 100 ha in China, identifying their types, areas and distributions, up to an entire area of 38 million ha of wetlands. Second, they identified the composition of wetland higher plants and the species and distribution of the rare ones. According to the survey, there was a total of 2,276 species of higher plants in China’s wetlands. They fall into 815 genera of 225 families, including bryophytes of 64 families, 139 genera and 267 species; ferns of 27 families, 42 genera and 70 species; gymnosperm of four families, nine genera and 20 species; and angiosperm of 130 families, 625 genera and 1919 species. Third, the researchers examined the wetland animals in China, including amphibians, reptiles, birds, beasts, fishes, and defined their species, geographical distributions and natural habitats (especially the rare species). The survey showed that the nation’s wetland trove was home to wild animals of 25 orders, 68 families and 724 species, including birds of 12 orders, 32 families and 271 species; amphibians of three orders, 11 families and 300 species; reptiles of three orders, 13 families and 122 species; and beasts of seven orders, 12 families and 31 species. The CAS Wetland Research Center has been actively involved in the ongoing second national wetland survey, which was initiated in 2009.

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Wetland plant communities dominated by Typha latifolia in the Longfeng Wetland in northeast China (photo by Zhao Kuiyi)

2.3 Wetland research stations In 1986, NEIGAE established an experimental station for wetland observation in northeast China’s Tongjiang City, the hinterland of the Sanjiang Plain. The Sanjiang Station became a base station of the Chinese Ecosystem Research Network (CERN) in 1992 and a state-level field station in 2005. Focusing on marsh and wetland studies on the Sanjiang Plain, the station carries out long-term monitoring of major ecological components and processes of the local wetlands. It is now a center for the comprehensive study of various ecological processes, resource protection, and ecological and environmental safety management of wetlands, and is the first key station in China for research into wetland and marsh ecology. In 2009, NEIGAE set up another three wetland observation stations in northeast China: the Xingkai Lake Station in Jixi City, Heilongjiang Province, the Daxing’anling Station in the Greater Khingan Range, and the Panjin Station in Panjin City, Liaoning Province. A wetland work station for CAS academicians at Minjiang River estuary was officially set up on June 21, 2010. Prof. LIU Xintu, a senior researcher with NEIGAE and Member of the Chinese Academy of Engineering cut the ribbon for its inauguration. As the first of its kind in China, the work station will conduct the monitoring of wetland ecology, implement wetland protection and rehabilitation, and build up a wetland database as well as a base station for PhD internship (Media: Wetland China, by Fujian Minjiang Hekou wetland 2010.6.23). The CAS Nanjing Institute of Geography and Limnology has made significant contributions to the study of river and pond wetlands. As early as in 1988, it founded

a work station by the Taihu Lake for ecological observation and research, which now as a field station of CERN shoulders major fieldwork of scientific monitoring in south China. In 2008, another comprehensive research station was set up by the CAS Nanjing Institute by the bank of Poyang Lake in Xingzi County, Jiangxi Province. The Poyang Lake Station now comprises of a standard weather station, several laboratories for biological, ecological, chemical and hydrological studies and a number of core facilities. It is going to build more experimental sites for materials transportation modeling, lake wetland ecology restoration and wetland plant ecology, as well as a lake-based automated hydrologic monitoring station. By far, several monitoring sites for the study of hydrology, weather, water resources and biology are operational on the periphery of Poyang Lake to regularly monitor the wetland resources in the area.

3 Conservation of wetland resources 3.1 Ex situ conservation of aquatic plants As a complex ecological group, freshwater angiosperms are secondarily aquatic. Based on traditional and modern molecular phylogenies, the return of different angiosperm families to the aquatic environment appears to have occurred often, maybe around 100 times (Cook, 1996). Many unusual evolutionary patterns of aquatic plants have received close attention (Barrett, Eckert, & Husband, 1993). With high economic, ecological and scientific values as well as unique biological and ecological characteristics, aquatic plants are an ideal group for biodiversity study both in theory and practice. The wetland is one of the habitats most seriously threatened in China. Habitat loss and fragmentation, water


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pollution and eutrophication and other factors greatly endanger the survival and growth of many aquatic plants, leading to the rapid decline or even extinction of many populations (Yu et al., 1998). Ex situ conservation is a main way to maintain the sustained survival of aquatic plants. The Wuhan Botanical Garden (WBG, formerly the Wuhan Institute of Botany) of CAS is one of the first national research institutes that carried out a comprehensive study into aquatic plants, which has been one of the garden’s main research domains since its foundation in the 1950s. Earlier research was focused on the taxonomy of aquatic plants and the collection, development and utilization of those with commercial or ornamental values (lotus and water lily for example), and was summarized in two monographs: Atlas of Aquatic Vascular Plants and Lotus of China (Wang, Zhang, & Huang, 1983; Ni and Zhao, 1987). Since the commencement of the Knowledge Innovation Program, WBG has become a key institute on aquatic plant study and a main base for ex situ conservation of aquatic macrophytes (following the definition of Cook, 1996). Now WBG has built the world’s largest collection of aquatic plant germplasm, preserving 421 species of aquatic higher plants (including all the rare and endangered species), and ca. 580, 150 and 30 varieties of lotuses, water lilies and fleur-de-lis respectively. All the collections provide abundant resources We t l a n d p l a n t c o m m u n i t i e s d o m i n a t e d b y M i s c a n t h u s sacchariflorus in the Poyang Lake in east Jiangxi Province (photo by

Zhao Kuiyi)

for the biological study of aquatic plants and the filtration and improvement of relevant germplasms. 3.2 Seedbanks and the conservation of aquatic plant diversity Seedbank is a common name for all the potential plant populations composed by organs capable of reproduction in soil, including vegetative propogules (rhizome etc.), seeds, moss fragments and spores (Li et al., 2002). The middle and lower reaches of the Yangtze River is now a main area in China for research into wetland seedbanks (Liu et al., 2007). Significant differences appear between hydrologically connected permanent marshes (fed by local runoff) and lakeshore marshes (more closely connected to a regulated river) in their species composition and distribution of seedbanks in this area. And different spatial scales played important roles in controlling their species diversities. Despite the potential for dispersal of propagules via the annually pulsing river system (hydrochory), at a regional and landscape scale, biodiversity is maintained mainly by large-scale temporal hydrological heterogeneity and smaller scale spatial and topographic heterogeneity (Liu et al., 2006a). Seedbanks usually show higher species diversities than the corresponding standing vegetation, and lower frequency genes of the endangered wetland plants, such as Oryza rufipogon Griff., were detected in its seedbank, which suggested the potential roles of seedbanks in conserving endangered plants and serving as the germplasm resources for wetland vegetation restoration (Liu et al., 2006b). Seedbank manipulation is considered a valuable way to restore the damaged aquatic ecosystems (Li, 2008). 3.3 The fishing ban and ecological restoration of rivers, lakes and wetlands in China The middle and lower reaches of the Yangtze River is a suitable habitat for fishes to dwell, as there are plenty of streams and lakes in the river. However, human activities are seriously undermining the restoration of fish population. Each year, a brief fishing ban period is followed by a more destructive practice of fishing. In order to restore fish population in the wetlands of middle and lower reaches of the Yangtze River, the introduction of a year-long fishing ban is needed. The possibility of fish population restoration would be slim unless effective measures are taken.

A Future Perspective Wetland biodiversity Study on the relationship between fish phylogenetics, molecular clock resetting and paleoclimate can be used to


evaluate the historical formation of wetland biodiversity. Fish makes up an important part of wetland biodiversity. Fish fauna results from the interaction between organisms and the wetland environment. Its formation is closely related with

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the changes of the wetland environment and paleoclimate. To protect fishes, we must learn more about the evolutionary process of their biodiversity so as to come up with specific protection strategies and methods. By reconstructing molecular phylogeny, resetting molecular clock and applying biogeography, we can obtain data on the formation process and formation time of fish biodiversity in a designated region. With data of paleogeography and paleoclimate, we can deduce the spatial and studies can provide theoretical and technological guidance for us to formulate protective measures. For instance, the molecular phylogenetic analysis of Cyprinidae reveals the independent origin of Eastern Asian Cyprinidae which originated from within the time range of 10 millions years ago and was greatly influenced by East Asian Monsoon (Liu & Chen, 1998). Research also finds that the fish fauna in the wetlands of middle and lower reaches of Yangtze River is vulnerable. If we do not set up more conservation regions and still neglect the long-term fishing moratorium practice, the restoration of fish population in these regions is likely to fail. To study seedbanks for recovering and reconstruction of wetlands A close relationship has been demonstrated between the wetland vegetation dynamics and its seedbank composition both quantitatively and qualitatively. The biological rhythm and seasonal variation of the above-ground vegetation can affect the seedbanks, and propogules in the seedbanks can participate in the turnover and succession of above-ground vegetation. More reserves and reserve networks are needed for the restoration and reconstruction of wetlands. A thorough fishing ban and development moratorium is required for restoring a healthy wetland environment for the recuperation of its organisms. In general, wetlands support higher biodiversity than land habitats do, and the wetland itself is an important germplasm pool, which means that conserving wetlands equals to building a germplasm bank.

Germplasms of wetland species To launch special investigations on germplasms of wetland species The plant germplasms of a marsh is the foundation of the sustainable development of our society, economy and people’s well-being. It is also one of the important fundamental resources for global strategic competition and national ecological security. The germplasm resources of wetland species, and those of wetland plants in particular, haven’t been systematically investigated, and little data is available so far. Hence, more investigation is needed. To establish a platform for sharing germplasm information on wetland species and organisms


A platform for sharing germplasm resources is crucial for researchers to work out strategies on the protection of wetland biodiversity across the country. Via a distributed database system we can integrate information about species biodiversity in wetlands in an all round way. The use of supercomputer and the establishment of the biodiversity database will effectively strengthen our monitoring over wetland biodiversity.

Monitoring of wetland biodiversity To establish a DNA-based identification system, a biodiversity information inquiring system and a real-time monitoring network Wetlands boast abundant varieties of species. The survey of such a complex system requires species identification conducted by multidisciplinary experts. However, the number of such experts available is too small for a largescale survey. What we need is an information inquiring system on biodiversity and a DNA-based identification system to meet the demand of wetland biodiversity conservation. Both systems can identify the taxonomic characteristics of samples rapidly through DNA sequencing and access to the internet (Hebert et al., 2003; Peng, Wang, & He, 2008). In fact, the DNA-based identification system is an extension of expert identification, and DNA sequencing is a media that connects the samples with the already identified specimens. A real-time monitoring system of the wetland can send data about wetland biodiversity and animal behaviors back to a computer platform for analysis with the help of LAN, Internet and different probes (above-water, underwater, hydrological, atmospheric or meteorological probes). It can help us accurately assess the biodiversity status of a designated area. For instance, the real-time monitoring system of the birds in the Bird Island, Qingdao Lake can accurately report the local ecology and the behavior of birds. To use e-Science, phylogenetic analysis and population genetic diversity for the evaluation of the historical formation of wetland biodiversity. The use of a supercomputer and the establishment of a massive database can greatly improve our monitoring ability on wetland biodiversity. For instance, we can use the method of e-Science to observe the behavior and population of birds and fishes. By placing infrared or visible-light probes underwater or on the land and connecting them to the monitoring network, scientists can carry out remote analysis with the image and data sent back by the probes via LAN and the Internet. Also, DNA barcode can be applied to identifying and managing the diversified wetland species, which is conducive for the sustainable utilization of species resources.


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Networking for conservation of wetland plant diversity (1) To enhance the construction of field stations Biodiversity conservation needs lasting efforts. By far, several different conservation systems have been built for wetland ecosystems, and many independent information systems for aquatic plants are also completed based on systematic classification. But there is still a long way to go for us to build a conservation network for wetland biodiversity preservation.

(2) To set up an integrated conservation system Although ex situ conservation of aquatic plants has achieved great progress, it is based on the collection of limited organism individuals which might lead to the gradual degradation of conserved species and the instability of aquatic vegetation in the long run. Therefore, an integrated conservation system should be built based on the traditional ex situ conservation. Some suggestions are as follows.

References

Barrett, S. C. H., Eckert, C. G., & Husband, B. C. (1993). Evolutionary process in aquatic plant populations. Aquatic Botany 44, 105–145. Cook, C. D. K. (1996). Aquatic plant book. Amsterdam: SPB Academic. Editorial Committee of Wetland vegetation of China. (1999). Wetland vegetation of China (pp.17-553). Beijing: Science Press. Hebert, P. D. N., Cywinska, A., Ball, S. L., & deWard, J. R. (2003). Biological identification through DNA barcodes. Proc. R. Soc. Lond. B. Biol. Sci. 270, 313-321. Huang, X.C. (1988). “An approach to the distribution and development law of mires”. In Huang Xichou (Ed.), Study of mires in China (pp.1-8). Beijing: Science Press. Huang, X.C. (2003). On building wetland science in China — Congratulations to the inauguration of Wetland Science magazine. Wetland Science 1(1), 2-6. Ji, Z.C. (1995). “Wetland study in ancient China and its historic contributions and significances”. In Chen Yiyu (Ed.), Study of wetlands in China (pp.104-108). Changchun: Jilin Science and Technology Publishing House. Li, W. (2008). Theory and methodology of restoring aquatic plant communities in eutrophicated lakes. Journal of Hydroecology 1(1), 8-13. Li, W., Liu, G. H., Zhou, J., & Huang, D.S. (2002). Studies on the seed bank of freshwater wetland: A review. Acta Ecologica Sinica 22(3), 395-402. Liu, G. H., Li, W., Li, E. H., Yuan, L. Y., & Davy, A. J. (2006a). Landscape-scale variation in the seed banks of floodplain wetlands with contrasting hydrology in China. Freshwater Biology 51, 1862-1878. Liu, G. H., Luo, L. M., Wang, B., Li, W., & Song, Z. P. (2006b). Comparison of genetic variation in populations of wild rice, Oryza rufipogon, plants and their soil seed banks. Conservation Genetics 7, 909-917. Liu, G. H., Xiao, C., Chen, S. F. & Zhang, Q. F. (2007). Roles of soil seedbanks in wetland restoration and biodiversity conservation in the middle-reaches of the Yangtze River. Progress in Natural Science 17(6), 741-747. Liu, H. Z., & Chen, Y. Y. (1998). Distribution pattern of freshwater fishes in China and its evolution in East Asia. Acta Animal Taxonomy Sinica 23, 10-16. Liu, X.T., Deng, W., & Liu, J.S. (2006). An introduction to mire science (pp.1-331). Changchun: Jilin Science and Technology Publishing House. Ni, X. M., & Zhao J. R. (1987). Lotus of China (pp.1-125). Beijing: Science Press. Niu, H.G., & Zhang, Y. Z. (1988). “Mires in Northeast China”. In Huang Xichou (Ed.), Study of mires in China (pp.46-58). Beijing: Science Press. Peng, J. L., Wang, X. Z., & He, S. P. (2008). Research and application of DNA barcoding technologies. Acta Aquatic Biology Sinica 32(6), 916-919. Wang, H.Q. (1999). Mire maps of China. Beijing: Science Press. Wang, N. Z., Zhang, S. F., & Huang, R. H. (Eds.). (1983). Atlas of Aquatic Vascular Plants in China. Wuhan: Hubei People’s Press. Wang, Z.Q., Sun, L. H., & Yi, F. K. (1995). A primary catalog of terrestrial animals in wetlands of China. In Chen Yiyu (Ed.), Study of wetlands in China (pp.307-356). Changchun: Jilin Science and Technology Publishing House. Yu, D., Zhong, Y. X., & Tu, M. H. et al. (1998). Study on endangered aquatic plant species in China. Biodiversity 6(1), 13-21. Zhang, N. M., & Chen, Y. Y. (2000). The distribution patterns of fish flora in late Mesozoic and Tertiary China. Acta Vertebrate Palaeontology Sinica 3, 161-175. Zhao, K.Y. (1999). Mires of China (pp.3-718). Beijing: Science Press. Zhao, K. Y. (2006). Wetland vegetation. In Liu Xingtu, Deng Wei & Liu Jingshuang (Eds.), An outline of mire science (pp. 177-221). Changchun: Jilin Science and Technology Publishing House. Zhao, K.Y., Zheng, X.F., & Yi, F.K. (1995). A primary catalog of wetland plants in China. In Chen Yiyu (Ed.), Study of wetlands in China (pp.307-356). Changchun: Jilin Science and Technology Publishing House.
