Wetland Biodiversity Conservation and Sustainable Use in China
(CPR/98/G32/A/1G/99)
REPORT A.2
ASSESSMENT OF
BIODIVERSITY HOT-SPOTS
IN YANCHENG MARSHES,
JIANGSU PROVINCE, CHINA
by
Dr. XUE Dayuan
Biodiversity and Management Planning Specialist
assisted by
Dr. Nick Willoughby (International consultant) for editorial help, and
Dr. AN Shuqing (National consultant) for field work
Drafted April 2001: submitted September 2001
TABLE OF CONTENTS
Executive Summary (English)
Executive Summary (Chinese)
Section 2: BIODIVERSIY BACKGROUND IN YANCHENG COASTAL MARSHES
2.1 Location and Range
2.2 Physical Features
2.3 Biodiversity Features
2.3.1 Vegetation and successions
2.3.2 Species diversity
2.3.3 Biodiversity importance
Section 3: DESCRIPTION OF THE POTENTIAL HOTSPOTS
3.1 Criteria for Hotspot Selection
3.2 Descriptions of Potential Hotspots
3.2.1 Hotspot 1: Quandong Salt Farm and adjacent areas
3.2.2 Hotspot 2: Sheyang Salt Farm and adjacent areas
3.2.3 Hotspot 3: The core area of YNNR
3.2.4 Hotspot 4: Dafeng coastal marshes
3.2.5 Hotspot 5: Dongsha Islands
3.3 Threats to Potential Hotspots
Appendix 1: Worksheets of the mission’s field surveys (No.1 to No.5)
Appendix 2: Photos to Show Biodiversity in Yancheng Coastal Marshes
LIST OF ACRONYMS & ABBREVIATIONS|
CPMU |
Central Project Management Unit |
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DMNNR |
Dafeng Milu National Nature Reserve |
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GDSF |
Guandong Salt Farm |
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GEF |
Global Environment Facility |
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GXSF |
Guanxi Salt Farm |
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IUCN |
International Union for the Conservation of Nature and Natural Resources |
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MAB |
Man and Biosphere Programme (of UNESCO) |
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PAFD |
Provincial Agriculture and Forestry Department |
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PAS |
Protected Areas System |
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PEPB |
Provincial Environmental Protection Bureau |
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POD |
Provincial Oceanic Department |
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PPMU |
Provicial Project Management Unit |
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RDB |
Red Data Book |
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SEPA |
State Environmental Protection Administration |
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SFA |
State Forestry Administration |
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SOA |
State Oceanic Administration |
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SSF |
Sheyang Salt Farm |
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UNDP |
United Nations Development Programme |
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UNESCO |
United Nations Educational, Scientific and Cultural Organisation |
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YMG |
Yancheng Municipal Government |
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YNNR |
Yancheng National Nature Reserve |
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LIST OF MAPS
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EXECUTIVE SUMMARY (English)
Yancheng coastal marshes are located in the coastal zone of Jiangsu Province, East China. They stretch along the seashore line of the Yellow Sea for 582 km from north to south, ranging from 32o34’ N to 34o28’ N and 119o48’ E to 120o56’ E, from the sea dyke made in 1950s (as the western border) to the sea water (as the eastern border). The total area is 4553.3 km2, composed of 1673 km2 of above-tidal land, 1613.3 km2 of inter-tidal land and 1267 km2 of radiation sandbars.
In 1983, Yancheng National Nature Reserve (YNNR) was established for conserving rare birds and their habitats. Its core area is located in the center of the coastal marshland stretch, and the buffer zone and experiment zone covered the rest of the Yancheng marshes. Three year later, Dafeng Milu National Nature Reserve (DMNNR) was founded in Dafeng coastal area specially for the conservation and naturalization of Pere David’s Deer, a species which was extinct in China and was reintroduced from England.
Nowadays, a big proportion of this coastal marshland is interspersed with salt pans and aquaculture schemes, protected from the sea by dykes. Also a huge area of farmland has been developed for crops of cotton, rice, rape seeds, etc. As the local economy has developed very fast in the past years, some industries and harbor constructions are also appearing in the marshland. These activities have drained much of the brackish lakes and marshes and have led to the loss of a great proportion of the original wetland habitats.
However, this marshland still represents one of the most important areas for waterbirds in Asia, especially for the period of winter, when a huge number of wintering migratory waders, ducks, geese, and seabirds pass through the mudflats. As the marsh area has a rich biodiversity, YNNR was designated as a UNESCO Man and Biosphere Reserve in 1992 and was admitted as Northeast Asian Crane Reserve Network Site in 1997 and as an East Asia-Australian Migratory Shorebirds Network Site in 1999.
The vegetation in the coastal marshland is relative simple and usually dominated by saline plants. The vegetation can be divided into five different vegetation types with 14 main communities, such as Suaeda salsa and S. glauca, Salicornia europaea, Zoysia macrostachys, Aeluropus littoralis, Imperata cylindrica, Spatina anglica and S. alterniflora, Carex scabrifilia, Scripus planiculmis, Phragmites communis, Thyha anyustifolia, etc. Of the communities, Spartina is an alien plant introduced from Europe in 1960s for erosion protection, but it has spread out everywhere in saline wetlands. A unique vegetation succession is happening in the mudflats. As the salinity and humidity change, the previous communities are being replaced by the later ones.
Based on the concentrated scientific surveys conducted in the 1980s by a large team organized by Jiangsu Province Government and following surveys by YNNR, Yancheng marshes is known to contain a rich biodiversity. About 190 species of photoplankton and 98 of zooplankton are identified in seashore area`s. For inter-tidal animals, there are 53 species of annelids, 87 molluscs, 42 crustaceans and 16 others. There are rich shellfish resources in the mudflats with the main species being Meretrix meretrix, Cyclina synensis, Malta veneriformis, Bullacta exarata, and Onchidium struma. It is recorded that 183 benthic species are distributed in the inshore waters, of which 31 species are annelids, 78 molluscs, 62 crustaceans, 4 coelenterates, 6 echinoderm and 2 others. About 150 fish species are distributed in the inshore areas, belonging to 17 orders, 73 families and 119 genera. Furthermore, 19 species of amphibians and 47 mammals are identified in Yancheng marshlands, including the re-introduced Pere David’s Deer (Milu) with a herd of 462 head, and a native species of Chinese river deer which is listed for national protection. In addition, 311 plant species are recorded of which 223 are higher plants.
The bird diversity reflects the biodiversity importance in the area. In the 1980s provincial comprehensive surveys, only 104 bird species were recorded, but following surveys have revised their records. Now the record has been increased to 377 species belonging to 18 orders and 44 families, of which 45 species are residents and 332 are migrants. Many migrants are of international importance, among them being the following 8 species:
l Red-crowned Crane (Grus japonensis). An endangered IUCN Red Data Book Species. The core area of YNNR and surroundings support 30%-65 % of the entire world population of the crane during winter including almost the whole of the Chinese wintering population. YNNR and the adjacent areas supported a maximum of 1128 individuals in winter of 1999.
l Black-faced Spoonbill (Platalea minor). This is an IUCN Red Data Book species, with a very restricted global range. The core area of YNNR and Dongsha Islands supported a maximum of 48 birds in 1997, comprising almost 10% of the world population. This makes this area a very important site for this species.
l Saunder’s Gull (Larus saundersi) is a rare and endangered species in the world and is mainly confined to the eastern coast of China where it breeds and winters. The species is recorded throughout the coastal marshes. It was recorded at a maximum of 3000-4000 birds in 1994, comprising 80% of the world population for breeding and 30% for wintering there. The population has decreased since 1995.
l Spotted Greenshank (Tringa guttifer) is an another IUCN Red Data Book species. A total of 12 birds was recorded in Guandong Salt Farm in 1990. This comprises 1% of the estimated world population, thus fulfilling 3c of the Ramsar criteria.
l Red Knot (Calidris canutus). A single count of 1809 birds was recorded in Xintian Salt Farm in spring 1990. It is close to the 1% estimate of the global population of this species, indicating that this particular area may be of great importance to this species during the spring migration.
l Bean Goose (Anser fabalis). A count of 4950 birds was recorded in the core area in winter of 1996, supporting about 20% of the world population of this species. Another big count was of 3071 birds in Jan, 1992. These make the core area of YNNR very important for the Bean Goose.
l Swan Goose (Anser cygnoides). A single count of 738 birds was recorded in the core area of YNNR in winter 1996, comprising 1% of the world population of the goose.
l Greylag Goose (Anser anser). This goose also winters in the core area of YNNR. More than 1% of the world population is regularly recorded there. A count of 1371 in winter 1991 and another count of 4150 in winter 1996 were recorded in the core area of YNNR.
In line with the Ramsar Convention “Criteria for Identifying Internationally Important Wetlands” and Chinese “Criteria for Reserve Establishing”, five biodiversity hotspots were selected. They are Guandong Salt Farm and adjacent areas, Sheyang Salt Farm and adjacent areas, the core area of YNNR, Dafeng coastal marshes and Dongsha Islands. The bird biodiversity and international importance in these hotspots are all described in the report in order from north to south, mainly based on the data of bird surveys conducted in 1989/1990, 1991/1992, and 1996/1997.
The mission’s team made a field survey to all the proposed sites except Dongsha Islands which are difficult to access to. The team consisted of two international consultants, two national consultants and two scientific staff from YNNR. The survey lasted two weeks from Feb 26 to Mar 8, 2001, covering over 1000 km through the marshes. Though it was too late for a full survey of wintering birds, we still counted thousands of birds. The results of this survey have been incorporated into the descriptions and summarized data tables.
Guandong Salt Farm (GDSF) is located in the most northerly of the Yancheng marshes. It, together with the adjacent areas of Chenggang Shrimp Farm, Xinhuahe River Estuary Mudflats, Xintian Salt Farm and Quanxi Salt Farm (GXSF), has an area of 42,597 ha. On Oct 17, 1991, a single count of 42,511 birds was made in GDSF. Some rare birds such as spotted greenshank, Saunder’s gull, spoon-billed sandpiper, red-crowned crane and oriental white stork were recorded there.
Sheyang Salt Farm (SSF) is located in the buffer zone of YNNR near the core area. Its area is 26627 ha, together with adjacent Sheyang River estuary and the mudflats outside SSF. From 1990/1991 to 1996/1997, all the counts were up to over 100,000 wintering waterbirds, mainly of ducks and coots in the salt reservoirs of SSF. A large number of red-crowned crane and Saunder’s gull were counted, oriental white stork, black stork and spotted greenshank were also recorded
The core area of YNNR is the richest site for biodiversity compared with other hotspots. It is strictly protected and has an area of 17400 ha. Over 90 bird species have been recorded here including 433 red-crowned crane, 32 black-faced spoonbill, 24 oriental white stork and 410 Saunder’s gull recorded in the core area. A large flock of geese roost regularly here, with counts of 4,950 birds for bean goose, 738 for swan goose and 4150 for greylag goose.
Dafeng Coastal Marshes include several small hotspots of Si-mao-you mudflats (<2,000 ha), Wanggang/Dafeng Harbor areas (1,500 ha), Zhu/Chuan Mudflats (<3,000 ha) and the new core area of DMNNR (1,000 ha). There are not enough data available, but their importance is reflected in the rich biodiversity by the surveys in Si-mao-you area in 1991/1992 and 1996/1997. For example, 200 red-crowned crane, 429 Saunder’s gulls and over 5000 geese were recorded.
Dongsha Islands are located in the Yellow Sea near the southern Yancheng coast (32°55’ N 120°57’E to 33°19’N 121°21’E). They cover an area of over 70,495 ha above the zero low water mark. The survey in Sept 1997 counted over 250,000 birds mostly waders. Black-faced spoonbills were regularly recorded with a flock of 48 birds in 1997. Besides, 280 Saunders’ gulls and 305 relict gulls were counted.
The threats upon the hotspots are analyzed. These are mainly land use change (from salt pans to aquaculture ponds), marshland reclamation, industrial pollution, harbor construction and resource collection. Furthermore, conservation priorities and mechanisms are suggested in the report as below:
l To enhance the conservation in core area and try to maintain the original size of the core area;
l To establish conservation areas in Quandong Salt Farm and Sheyang Salt Farm;
l To establish strictly protected spots and conservation areas in Dafeng coastal marshes;
l To establish a new national wetland reserve in Dongsha Islands;
l To merge YNNR with DMNNR and set up a combined management mechanism in order to co-ordinate the conservation and sustainable use of the whole Yancheng coastal marshes.
EXECUTIVE SUMMARY (Chinese)
Section 1: INTRODUCTION
China has a large area of natural wetland distributed throughout the whole country. These wetlands are habitats for endangered or endemic plants and animals, and crucial staging and breeding areas for migratory bird populations, including many globally threatened species. However, due to a very big human population and food pressures in the country, many natural wetlands are under a constant threat of degradation, and a lot of significant lakes and coastal marshes have been dyked and used as farmlands. Along with the loss of wetlands go their economic values and benefits, such as the amelioration of flooding and local climate, and especially the loss of biodiversity.
There is an urgent need to conserve the biodiversity of wetlands and to use wetland resources for sustainable socio-economic development of local communities. The Chinese Government has paid great attention to the protection of the eco-environment. Recently, the Central Government issued the National Eco-protection Strategy, and a series of major counter-measures will be enforced during the next few years, including actions on wetland conservation.
International society has also responded to the challenge of wetland biodiversity conservation and sustainable use in China. In January 1999, the Global Environmental Facility (GEF) awarded the Government of China US$ 11.7 million to fund its initiatives on protection of wetlands in the country. Together with assistance from Australian Aid (US$ 2.592 million), parallel financing from OECF/Japan (US$ 1.5 million), UNDP (US$ 0.34 million), and the Chinese Government (US$ 20.297 million), this China/GEF-UNDP Project was launched in December 1999 for “Wetland Biodiversity Conservation and Sustainable Use in China”.
The Project is focused on the management of four distinct and representative wetland sites with globally significant biodiversity representing the full range of wetland biodiversity and socio-economic conditions in China. One of the selected four sites is Yancheng coastal marshes, Jiangsu Province, which include YNNR (Yancheng National Nature Reserve) and DMNNR (Dafeng Milu National Nature Reserve).
Yancheng coastal marshes stretch for 582 km along the coast in Jiangsu Province. The biotope is the most extensive example of inter-tidal mudflats, tidal creeks and river channels, salt marshes, reed beds and marshy grassland remaining in China. YNNR was designated in 1983 to protect the marshes ecosystem and migrating birds. It was also designated as a UNESCO Man and Biosphere Reserve in November 1992, as a Notheast Asian Crane Reserve Network Site in March 1997, and as an East Asia-Australian Migratory Shorebirds Network Site in 1999. The reserve is of global biodiversity significance as a habitat for rare and threatened waterbirds. The another important protected area, DMNNR was established in 1986, designated for the re-introduction of Pere David’s deer (Elaphurus davidianus) which originally lived in the area before it became extinct in the wild area in the 20th Century. DMNNR was extended by 1000 ha of mudflats which were to its core area in 1999.
The China/GEF-UNDP Project Document plans for a biodiversty and management plan scientist and an integrated coastal zone management planning specialist to work in Yancheng marshes to provide technical input and supervision to the protected area system (PAS) management and development. Under the arrangements of the Central Project Management Unit (CPMU) in Beijing and Jiangsu Provincial Project Management Unit (PPMU) in Nanjing, a core team was set up consisting of two international consultants. This pair was joined by two national consultants and assisted by several staff from YNNR and DMNNR during the field surveys. The team was divided into two sub-groups: Biodiversity Team and Planning Team.
In line with ToRs of the two international consultants, one focus for the team was to propose an expansion and re-alignment of the PAS to include additional biodiversity hotspots and coastal wetland eco-clines, and to improve PAS management and protection of globally threatened biodiversity in the core areas of YNNR. Aimed at the potential biodiversity hotspots, this mission made a field survey between Feb 26 and March 8, along the coastal marsh area. The team consisted of two international consultants (Dr. Nick Willoughby and Dr XUE Dayuan), two national consultants (Dr AN Shuqing and Ms CHEN Xiaoli), and two technical staff (Mr WANG Hui and Mr GAO Zhidong) from YNNR. Starting from Yancheng City, the team visited Quanyun, Xiangshui, Binhai, Sheyang, Dafeng and Dongtai counties. Field surveys were conducted from north to south in Quanxi Salt Farm, Quanhe River estuary, Quandong Salt Farm, Bian-dan-he estuary, She-yang-he estuary, Sheyang Salt Farm, the core area of YNNR, Wanggang mudflats, Dafeng Harbor and around areas, Zhugang/Chuan-dong-gang mudflats, core area of DMNNR, and Chuan-shui-gang estuary and mudflats. The survey covered more than 1000 km. Although it was not a good season because many wintering birds had already left the area, the survey revealed the significance of the potential areas, and several thousands of waterbirds are counted (worksheet in Annex 1). Some results of the field survey have been incorporated into this report.
During the past 10 years, many field surveys of birds counting have been conducted by experts, and some data are available, from the surveys in 1989/1990, 1991/1992, and 1996/1997. The biodiversity assessment in this report is mainly based mainly on this data.
Section 2: BIODIVERSIY BACKGROUND IN YANCHENG COASTAL MARSHES2.1 Location and Scope
Yancheng coastal marshes are located in the coastal zone of Jiangsu Province, East China (Map 1). They stretch along the seashore line of the Yellow Sea for 582 km from north to south, ranging from 32o34’ N to 34o28’ N and 119o48’ E to 120o56’ E, i.e. from the sea dyke made in 1950s (as the western border) to the sea water (as the eastern border). The total area is 4553.3 km2, composed of 1673 km2 of above-tidal land, 1613.3 km2 of inter-tidal land and 1267 km2 of radiation sandbars (Map 2). According to some documents, YNNR also covers 4553.3 km2, just the same area as that of Yancheng coastal marshes, so the concept of Yancheng coastal marshes is equal to YNNR for spatial distribution. The area covers all the coastal marshes under the jurisdiction of Yancheng Municipality including the five counties of Sheyang, Dafeng, Binhai, Xiangshui and Dongtai. The coast is accreting, with the mudflats moving about 100-300 metres/year seawards in the southern part of the area.
Although YNNR covers all Yancheng coastal marshes, it is not able to control all the land use within the area. According to the legal document issued by Yancheng Municipal Government in 1985, YNNR can legally control the land use only limited in the core area, about 17,400 ha, located in the border area between Sheyang and Dafeng counties. This ranges from the Xin-yang-gang estuary in the north to the Dou-long-gang estuary in the south; and from the Sea dyke (dyked in early 1950s) in west to minus 3.0 m depth of sea water in east. The rest of the large area marshes is designated as buffer zones and transition/experiment zones, but YNNR has been mandated only to protect birds and other wild animals within these zones, rather than controlling their land use.

Dafeng Milu National Nature Reserve (DMNNR) is located in the coastal area of Dafeng City (county level), about 140 km south of the core area of YNNR. DMNNR was set up in 1986, three years after YNNR. According to a legal document issued by Dafeng City in 1996, the reserve has since been extended to 2,666 ha for its whole core area. It now includes 1,000 ha of mudflats located outside the new sea dyke. This overlaps the transition zone of YNNR.
2.1 Physical Features
2.1.1 The climate
Yancheng coastal marshes are located in the transitional climatic zone between warm temperate and northern subtropical zones, receiving sunshine ranging from 2199 to 2362 hours per year and solar radiation ranging from 116.2 to 121.0 kcal/cm2 per year. The average temperature of January in winter ranges from minus 0.3 oC to minus 1.3 oC with an extreme minimum temperature of minus 17.3 oC. The average temperature of July in summer ranges from 26.7 oC to 27.4 oC with an extremely maximum of 39 oC. Annual precipitation ranges from 980 to 1070 mm, 70% of which falls between May and September. Catastrophic climatic events, including drought, flood, typhoon, cyclone, cold airwave and hail, often take place in the area.
2.1.2 The soil
From 1128 to 1855, the Yellow River had its estuary in the Yancheng coastal area, and brought a lot of sand and silt. It led to silting seawards during the period. In 1855, the Yellow River changed its course northwards to Shandong Province and the land accretion has slowed. Even erosion has been happening in the northern part of the marshes from the Guan River estuary to Biandan River estuary. From the low tide line to inland, the soil generally changes from saline soil to saline-tidal soil, mudflat soil, swamp soil, and meadow soil, though in some cases, this change order is simplified. .
2.1.3 The hydrology
The fresh ground-water in the coastal marshes comes mainly from the Huai River catchment and from local rainfall. There are more than 10 big river estuaries putting to Yellow Sea along the coastal line. These are the Guan River, the Zhongshan River, the Biandan River, the Abandoned Yellow River, the Sheyang River, the Huang-sha-gang River, the Xin-yang-gang River, the Dou-long-gang River, the Wanggang River, the Chuan-dong-gang River and the Dongtai River. The pH of their water ranges from 7.0 to 7.5, and the mineral degree ranges from 0.2 to 1.0 g/l in the northern and central parts, and >1.0 g/l in the southern part. The seawater submerges the inter-tidal mudflats by tides with an interval of 7-12 hours. The high tide range is 1.27 to 4.61m above datum. The seawater salinity ranges from 2.953% to 3.224%, and has a pH of 8.0.
2.2 Biodiversity Features
2.2.1 Vegetation and succession
Generally Yancheng coastal marshes are dominated by halophytic vegetation which can be divided into three different types within 14 main vegetation communities as follows:
(1) Land saline vegetation type
l Suaeda salsa + S. glauca Communities (Saline Seepweed and Common Seepweed). These are pioneer communities distributed in the salinized bare soils which are dispersed everywhere in the YNNR’s core area. The coverage can reach 50-80%. They are often replaced by Zoysia macrostachys (lawngrass) communities as the succession proceeds.
l Salicornia europaea Community (Marshfire Glasswort). These often grown sparsely and are mainly distributed in the abandoned reservoirs of salt farms.
l Zoysia macrostachys Community (Lawngrass). These are usually distributed in mudflats and cover a large area in the YNNR’s core zone and buffer zones. The coverage can reach 85%.
l Aeluropus littoralis var. sinensis Community (Chinese Aeluropus). These are mainly grown sparsely in salinized soils and are replaced by Imperata cylindrica communities as succession proceeds.
l Artemisia capillaris Community (Capillary Wormwood). This kind of community is sparsely distributed in bare mudflats and is gradually replaced by Imperata cylindrica communities.
l Imperata cylindrica var. major Community (Lalang Grass). As these communities are the final stage of the ecological succession, they usually cover large areas near the sea dyke. The coverage can reach to 70-80%. When the vegetation is developed to the lalang grass stage it indicates the soil has a reduced salt content and can be cultivated for farming use.
(2) Swamp saline vegetation type
l Spartina anglica + S. alterniflora Community (Cordgrass). The two cordgrass species were introduced from Europe in the 1960s. They are saline-tolerant with strong reproduction, and help soil silting and deposition. Now the cordgrasses are widely distributed and grow quickly. Usually Spartina grows in newly formed bare mudflats with a coverage of up to 90%.
l Carex scabrifilia Community (Scabrousleaf Sedge). This can be seen in the shallow swamps and is often replaced by reeds as the mudflats move seawards.
l Scripus planiculmis Community (Flatstalk Bulrush). This is usually distributed in estuary areas and is gradually replaced by reed communities.
l Phragmites communis Community (Reed). These grown widely in the swamp area, often with a large cover near the estuary areas. The coverage can be 60-70% and even up to 90-100% in some estuary reed beds. Reed communities will finally be replaced by Typha anyustifolia communities when the soil salinity is reduced.
l Typha anyustifolia Community (Narrowleaf Cattail). These are often mixed in reed communities and are distributed in river banks, ponds and brooks. As this kind of community is the final vegetation in swamp conditions, the coverage can be up to 90%.
(3) Saline aquatic vegetation type
l Ruppia rostellata Community (Beak Widgeonweed). This is the first seed plant community in the process of aquatic vegetation succession in coastal seawater. The communities are usually distributed in natural ponds along seashore lines and also live in abandoned salt pans. As the seawater is diluted they are replaced by Myriophyllum spicatum communities.
l Myriophyllum spicatum Community (Parrotfeather). This is distributed in rivers, brooks and ponds, where the community coverage can be up to 80%. As the water salinity decreases the communities are replaced by Potamageton crispus communities.
l Potamageton crispus Community (Curly Pondweed). This usually lives in water of up to 1 m in depth and with very lower salinity. As the water is reduced the community will be replaced by swamp vegetation.
2.1.1
Vegetation succession processes
As the soil or water salinity decreases, vegetation types will be succeeded by later one. The succession processes can be summarized as follows:
l The proto-succession process of land saline vegetation in the bare mudflats (community to community).
Zoysia macrostachys Imperata
cylindrica
l The vegetation succession process in secondary saline bare mudflats:
Suaeda salsa or Alenropus Artimisia Imperata
S. glauca littoralis capillaris cylindrica
l The succession process of swamp saline vegetation
Carex scabrifolia Scirpus planiculmis Reed Typha anyustifolia
l The succession process of aquatic saline vegetation
Ruppia Myriophyllum Potamogeton Swamp
rostellata
spicatum crispus plant
l The succession process of the artificial introduced Spartina
2.1.2
Species diversity
2.2.3 Species diversity
(1) Fauna and flora
Between 1980 and 1984, Jiangsu Provincial Government organized a large-scale field survey of natural resources in the mudflats of Yancheng coastal area. Hundreds of scientists from dozens of institutions and universities participated in the survey. Since that time, YNNR and DMNNR have also conducted many important resource surveys. The descriptions of the fauna and flora and their biomass in Yancheng marshes in this report are mainly based on these previous surveys.
l Plankton
Photoplankton are abundant in seashore area with 190 species identified as far, of which, 166 species are planktonic diatoms, 21 species are Pyrrophyta, 2 blue algae, and 1 golden algae. The floating diatoms are the dominant group, with four diatom species first records for China. These are Coscinodiscus perforatus, Cos. molleri, Cyclotella ladogensis, and Cyc. figida. Laver (Porphyra) is an economically important species in the coastal area, and during the mission’s field survey, some Porphyra farms were found in the seashore area near Guanxi Salt Farm.
98 zooplankton species have been recorded, of which 46 are water fleas, 33 jellyfishes, 2 Ctenophora and 17 others. The dominant species are Labidocera enchaeta, Calanus sinicus, Pseudeuphausis sinica, Sagitta crassa, etc.
l Inter-tidal animals
The Provincial Comprehensive Coastal Resources Survey showed that there are 198 animal species distributed in the inter-tidal mudflats, of which 53 species are annelids, 87 molluscs, 42 crustaceans and 16 others. The main economic species are Meretrix meretrix, Cyclina sinensis, Mactra veneriformis, Bullacta exarata (mud snail), Sinonovacula constricta (razor clam), Perinereis aibuhitensis (clam worm, or sand worm), Macrophthalmus japonicus (one kind of small crab), Moerella iridescens, Potamocorbula ustulata, Umbonium thomasi, Nassarius vericiferus,and Onchidium struma.
YNNR’s supplement surveys have increased the number of shellfish species and have clarified the resources amounts. The field investigation in 1993-1994 conducted by YNNR staff revealed that the shellfish resources within the whole Yancheng inter-tidal marshes (equal to the inter-tidal area of YNNR) was estimated as 31,058.46 ton in spring and 23,347.98 in autumn. The figures for the main species are listed in Table 1. The investigation showed that the distribution area for shellfish was about 154,000 ha, 14,580 ha less than in 1984, and decreasing at 4.7% per year, over the past nine years. The investigation also anticipated that the resource will decrease continuously because of over-harvesting and the land encroachment resulting from the artificially introduced plant, Spartina anglica, which now covers a very big area.
|
Shellfish species |
Common name |
Current resource deposit (ton/year) |
Current resource harvesting (ton/year) |
|
Meretrix meretrix |
Hard Clam |
3403.23 |
1500 |
Cyclina synensis |
Baby Clam |
1010.1 |
480 |
|
Mactra veneriformis |
Quadricorn Clam |
19929.88 |
7500 |
|
Bullacta exarata |
Mud Snail |
9726.81 |
2100 |
|
Onchidium struma |
Oncidium |
144.04 |
48 |
|
Total |
34214.06 |
11628 |
Data source: YNNR in 1995
l Inshore benthic animals
There are 183 benthic species distributed in the inshore waters (infauna and epifauna), of which 31 species are annelids, 78 molluscs, 62 crustaceans, 4 coelenterate, 6 echinoderm and 2 others. The dominant species are Arcasubcrenate lischke, Sepiola birostrata, Palaemon graviere, Penaeus arapenaeopsis, P. carinicauda, Trachypenaeus curvirostsis and Portunus trituberculafus. They are also economically important species for the inshore fishery.
l Nektonic species
About 150 fish species are present in the inshore area, belonging to 17 orders, 73 families and 119 genera. The dominant fish species are Setipinna taty, Collichthys lucidus, Pampus argenteus, Collia actenes, Trichiurus muticus, Pseudosciaena crocea, Ilisha elongata, Pampus cinereus, Scomberomorus niphonius, and Muraenesox cinereus,
There are 11 cephalopod species, of which 7 are nektonic cephalopods and 4 benthic species. They are Ommastrephes sloani pacificus, Loligo beka, L. bleekeri, L. japonica, Sepia andreana, S. esculenta, Sepiella maindroni, and the benthonic ones are S. birostrata, Euprymna morsei, Octopus ocellatus and O. Variabilis.
4 sea turtles and 9 sea mammals are recorded in the inshore area. The four turtle species are Eretmochelys imbricata, Caretta caretta gigas, Lepidochelys olivacea, Dermochelys coriacec,and the 9 mammals are Neophocaena phocaenoides, Pseudorca crassidens, Tursiops truncatus, Lagenorhynchus obliquidens, Balaenoptera physalus, B. edeni, Eumetopias jubata, Phoca largha, and P. hispida.
l Amphibians and reptiles
About 19 amphibians are distributed in the coastal marshes. The main species are Bufo bufo gargarizans, Rana nigromaculata, R. limnocharis and Kaloula borealis. 32 reptiles are recorded, the main species being Trionyx sinensis, Chinemys reevesii, Gekko swinhonis, Takydromus septentrionalis, Eumeces chinensis, Elaphe taeniura, E. rufodorsata, and Dinodon rufozonatum.
l Birds
There were only 104 bird species recorded by the Jiangsu Coastal Resources Comprehensive Survey during 1980 and 1984. However, as the reserve’s main management objective is to protect rare birds, YNNR has made a lot of bird surveys since 1984 and the results have supplemented and extended the original birds list. They have now identified 377 bird species belonging to 44 families and 18 orders, of which 45 species are residents and 332 are migrants. The important migratory wintering shorebirds include are Grus japonensis, G. grus, G. leucogeranus, Ciconia ciconia, Cygnus columbianus, C. cygnus, Platalea minor, and Larus saundersi. The detailed descriptions can be seen in Section 3.2.
l Mammals
Altogether 47 mammals have been recorded in the coastal zone including 12 marine mammals. However, very few mammal species live in the mudflats. The most important of these mudflat species is the Chinese River Deer (Hydropotes inermis). It is a nationally protected animal at “level 2”. The population of the deer was reported as 1700 head (Wang Hui 1993), but since 1993 the habitat area has been reduced dramatically through marshland reclamation. It is estimated that the population has dropped to less than 400 head and is limited to the core area of YNNR and DMNNR. The other mammals include Sorex araneus, Mus musculus, Rattus flavipectus, Lepns capensis, Pipistrellus abramus, Mustela sibirica, Felis bengalensis, etc.
Probably the most important mammal in the reserve area is Pére David’s Deer (milu in Chinese). It was re-introduced from England in 1986 and released in DMNNR as a partially captive animal. The population has increased from 39 to 462 by the end of 2000. In 1998, eight head of Milu were released to the wild and the wild herd has since increased to 10 head. It is expected that more animals will be released in the near future.
l Plants
Although 311 plant species were recorded in YNNR and 223 higher plants are listed in the Comprehensive Report of Scientific Survey in Jiangsu Milu Nature Reserve, the flora in coastal marshes is really not rich. As a special environment of salinized soil and water, the flora is just limited to dozens of plant species as listed in Table 2. It is significant to mention the exotic Cordgrass (Spartina anglica and S. alterniflora). Both of these were introduced from Europe in 1960s, but are now developed as dominant species in the salinized marsh vegetation.
|
Dominant plants distributed in the Land Saline Vegetation |
Dominant plants distributed in the Swamp Saline Vegetation |
Dominant plants distributed in the Aquatic Saline Vegetation |
|
Salicornia europaea, Suaeda salsa, S. glauca, Zoysia macrostachys, Aeluropus littoralis var. sinensis, Artemisia capillaris, Imperata cylindrica var. major, Calamagrostis epigejos, Phacelurus latifolius, Limonium sinensis. |
Spartina angelica, Carex scabrifolia, Scirpus planiculmis, Phragmites australis, Typha angustifolia. |
Ruppia rostellata, Myriophyllum spicatum, Potamogeton crispus, Ceratophyllum demersum. |
2.2.4 Biodiversity importance
(1) The habitats of internationally important species
Yancheng coastal mudflats are an important breeding and wintering site for many rare and endangered birds, some of which are of international significance. Due to its international importance, YNNR was received as a Northeastern Asian Crane Protection Network site in 1997, and admitted as an East Asia-Australia Shorebirds Protected Area Network site in 1999. Based on the data of field surveys during the past 18 years in YNNR, there are 31 bird species whose populations are more than 1% of their global populations. The other 10 birds have reached the Ramsar standard for stopping and rest.
l Red-crowned crane (Grus japonensis)
Red-crowned Crane is an endangered species listed in the IUCN Red Data Book. It breeds in Siberia (Russia) and in northeastern China, and winters in the coastal area of eastern China, with a boundary zone between North Korea and South Korea. About 600 individuals reside in Japan all the year. The wintering population in the reserve accounts for 30 - 65 % of the wild population in the world. It is estimated that the world population of red-crowned crane is about 2000. In addition, there is a traditional “Crane Culture” in China. The birds are usually taken as symbols of a long life, and a huge culture of products based on red-crowned cranes such as paintings, art, crafts and books are published or produced. Thus the bird is a widely known good-luck animal to all the people in China, and has become the flagship species for the Yancheng coastal marshes.
|
Years |
Core zoze |
Buffer zone (No) |
Experimental Zone (No) |
Total |
|
1982~1983 |
129 |
55 |
177 |
361 |
|
1988~1989 |
81 |
405 |
96 |
582 |
|
1989~1990 |
236 |
85 |
249 |
570 |
|
1990~1991 |
257 |
86 |
200 |
543 |
|
1991~1992 |
281 |
273 |
220 |
774 |
|
1992~1993 |
319 |
147 |
206 |
672 |
|
1993~1994 |
463 |
115 |
298 |
876 |
|
1994~1995 |
430 |
111 |
336 |
877 |
|
1995~1996 |
575 |
112 |
176 |
863 |
|
1996~1997 |
580 |
120 |
320 |
1020 |
|
1997~1998 |
795 |
|||
|
1998~1999 |
894 |
|||
|
1999~2000 |
1128 |
|||
|
2000~2001 |
898 |
Data sources: Liu Xi-ping, 1998 and YNNR
l Black-faced spoonbill (Platalea minor)
This is also an endangered species in the IUCN Red Data Book. The species breeds in Northeastern China and North Korea, and migrates to eastern China in the non-breeding period. The reserve harbors a maximum population of 38 individuals, comprising 10% of the world population.
l Saunder’s gull (Larus saundersi)
This is a rare and endangered species worldwide. The bird breeds in the coast of northeast China and eastern China and winters in the coast of eastern China and Southeast Asia. In 1994, nearly 4000 birds, about 80% of the world population bred in the reserve and 30% wintered there. The population has since decreased to about 2000.
l Spotted greenshank (Tringa guttifer)
This is an endangered Red Data Book species, 12 individuals of which were recorded in Guan-dong Salt Farm, within the experimental zone of YNNR. The population comprises 1% of the estimated world population.
l Red knot (Calidris canutus)
A single count of 1809 birds was recorded in Xintian Salt Farm in spring 1990. This is close to the 1% estimate of the global population of this species, indicating that this particular area may be of great importance to the species during its spring migration.
l Bean Goose (Anser fabalis)
A count of 4950 birds was recorded in the core area in the winter of 1996, respectively about 20% of the world population of this species. Another big count reached 3071 birds in January, 1992. These two counts indicate that the core area of YNNR is very important for the bean goose.
l Swan Goose (Anser cygnoides)
A single count of 738 birds was recorded in the core area of YNNR in winter 1996, comprising 1% of the world population of this goose.
l Greylag Goose (Anser anser)
This goose also winters in the core area of YNNR, with more than 1% of the world population regularly recorded there. A count of 1371 was made in winter 1991, and another count of 4150 in winter 1996 were recorded in the core area of YNNR.
l Pere David’s Deer (Elaphurus davidianus)
The species is endemic to China. It became extinct in the wild one hundreds years ago, but a linited and a limited population survived in the emperor’s garden. In the late 1800s, 18 animals were collected by British invaders who kept them in zoos and parks of England. Through a cooperation between IUCN, WWF and the Chinese Government, 39 head of the deer were re-introduced from England to China in 1986, and Dafeng Milu Reserve was specially established for their habitat. The captive population has extended to 452 head and another 10 animals are in the wild near the reserve.
l Chinese River Deer (Hydropotes inermis)
This endemic mammal is wildely distributed in the Yancheng marshes. However, the habitat becomes narrower and narrower the population has decreased from thousands to hundreds. It is estimated that only some 400 animals now survive in a few fragmentary marshes, mainly in the core area of YNNR and DMNNR.
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(2) Surviving refuge for the national protected species
Yancheng marshes are a refuge for many rare and endangered species, especially for birds. 70 bird species and 2 mammals recorded in Yancheng marshes are named in the List of Nationally Protected Animals, of which 12 species are at the Grade 1 and 60 are at the Grade 2 (Table 4). Also, many birds are listed as protected species under the Sino-Japan Agreement and Sino-Australia Agreement for Migratory Birds Protection. For example, more than 160 migratory bird species in Yancheng marshes are under the Sino-Japan Agreement, accounting for 70% of the whole 227 protected species. In addition, 17 waterbirds are listed in the China Red Data Book (RDB).
|
Species |
Natl. prot. Grade |
Breed-ing |
Resi- Dent |
Win. visitor |
Sum. visitor |
Pass- age |
Occa- sional |
China RDB |
Birds: |
||||||||
Red-necked Grebe (Podiceps grisegena) |
2 |
+ |
+ |
|||||
|
Horned Grebe (P. auritus) |
2 |
+ |
+ |
|||||
|
Spot-billed Pelican (Pelecanus philippensis) |
2 |
+ |
+ |
|||||
|
Eastern White Pelican (P. onocrotalus) |
2 |
I |
||||||
|
Sea Cormorant (Phalacrocorax pelagicus) |
2 |
+ |
+ |
|||||
|
Chinese Egret (Egretta eulophotes) |
2 |
P |
E |
|||||
|
Little Bittern (Ixobrychus minutus) |
2 |
+ |
||||||
|
Black Stork (Ciconia nigra) |
1 |
+ |
+ |
E |
||||
|
Oriental White Stork (C. boyciana) |
1 |
+ |
E |
|||||
|
White Ibis (Threskiornis melanocephalus) |
2 |
+ |
R |
|||||
|
White Spoonbill (Platalea leucorodia) |
2 |
+ |
+ |
V |
||||
|
Black-faced Spoonbill (P. minor) |
2 |
+ |
+ |
E |
||||
|
White-fronted Goose (Anser albifrons) |
2 |
+ |