Xiao County Old Yellow River Wetland Provincial Nature Reserve

Xiao County Old Yellow River Wetland Provincial Nature Reserve

The Xiao County Old Yellow River Wetland Provincial Nature Reserve is a provincial-level nature reserve.

Anhui Xiao County Old Yellow River Wetland Provincial Nature Reserve

I. General Overview

The Anhui Xiao County Old Yellow River Provincial Nature Reserve is based on the ancient course of the Yellow River. In 1194 AD, the Yellow River breached its banks in Yangwu, Henan, and flowed southward through Dangshan and Xiao County into the Huai River, eventually reaching the East China Sea. In 1855, the Yellow River changed its course northward, marking the end of its approximately 700-year flow through Xiao County. Currently, the Old Yellow River channel enters Xiao County from Xin Zhuang in the northwest, passing through the three towns of Yanglou, Liutao, with a total length of 46.6 km and a drainage area of 210.8 km². The Xiao County Old Yellow River Wetland Provincial Nature Reserve was approved for establishment by the Anhui Provincial People's Government in February 2012, covering an area of 3,200 km². Since 1956, the region has been under the administration of the two towns of Liutao and Yanglou in Xiao County.

The Xiao County Old Yellow River Wetland is located along the Old Yellow River channel and surrounding areas in the northeastern part of Xiao County, involving the towns of Xin Zhuang, Yanglou, and Liutao. Its geographical coordinates are between 116°42′51″ to 116°58′10″ east longitude and 34°18′44″ to 34°28′22″ north latitude.

II. Flora and Fauna Resources

Due to its location in the transitional zone from the warm temperate zone to the subtropical zone, the Xiao County Old Yellow River Wetland serves as a key stopover for many migratory birds. The favorable environment and abundant food sources have led to an increasing number of migratory birds resting and inhabiting the wetland. This area boasts relatively rich biological resources and is one of the most concentrated distributions of vertebrate species in Xiao County.

(1) Wetland Plants

According to survey and data analysis, a total of 68 plant species from 38 families have been recorded in the Xiao County Old Yellow River Wetland, including 30 species from 19 families of major aquatic vascular plants. Among these, there are 3 nationally protected Class II plant species: wild water caltrop, wild soybean, and lotus. The main cultivated economic plants in the wetland include fruit trees such as pear, peach, and apple, as well as aquatic plants such as lotus, cattail, and reed. Among the recorded plants, Poaceae, Cyperaceae, and Chenopodiaceae are dominant, with Poaceae having the highest number of species, totaling 11.

(2) Plankton and Benthic Animals

Plankton in the Xiao County Old Yellow River Wetland are mainly distributed in shallow river areas and marshes. Preliminary surveys have identified 23 species, including 4 species of protozoa, 12 species of rotifers, 4 species of cladocerans, and 3 species of copepods. Among the plankton, dominant species include Filinia longiseta, Polyarthra vulgaris, Diaptomus sanguineus, Eurytemora velox, Sinocalanus doerrii, and Canthocamptus calvus.

Preliminary surveys indicate that there are 15 species of benthic animals in the Xiao County Old Yellow River Wetland, mainly including hydrozoans from the Cnidaria phylum, oligochaetes and leeches from the Annelida phylum, freshwater snails and bivalves from the Mollusca phylum, and shrimp from the Arthropoda phylum. Common species include Pheretima communissima, Cipangopaludina chinensis, Anodonta woodiana, Hyriopsis cumingii, Procambarus clarkii, and river crabs.

(3) Fish and Amphibians/Reptiles

The Xiao County Old Yellow River Wetland is home to 30 fish species from 10 families across 5 orders. These include 22 species from 2 families of Cypriniformes, 2 species from 2 families of Siluriformes, 1 species from 1 family of Clupeiformes, 4 species from 4 families of Perciformes, and 1 species from 1 family of Gadiformes. Cyprinidae dominates the fish composition.

A total of 12 amphibian and reptile species from 6 families are found in the Xiao County Old Yellow River Wetland, comprising 6 species from 3 families of amphibians and 8 species from 6 families of reptiles. The overall species diversity is relatively limited, with 2 Anhui Provincial Class II protected animal species: the Bufo raddei and Bufo gargarizans. Among amphibians, Bufo gargarizans and Pelophylax nigromaculatus are the most common, while the other four species are relatively rare. Among reptiles, the Takydromus septentrionalis and Gekko japonicus are dominant, with other species being seldom seen or occasional.

(4) Mammals

The mammalian resources in the Xiao County Old Yellow River Wetland are all small-sized mammals, with a total of 10 species from 7 families across 5 orders. These include 2 species from 1 family of Eulipotyphla, 1 species from 1 family of Lagomorpha, 4 species from 2 families of Rodentia, and 1 species each from 1 family of Carnivora and Chiroptera.

(5) Birds

A total of 95 bird species from 32 families across 14 orders have been recorded in the Xiao County Old Yellow River Wetland, indicating a relatively rich species composition. Passeriformes has the highest number of species (40 species from 14 families), followed by Ciconiiformes, Anseriformes, Charadriiformes, Gruiformes, Falconiformes, Lariformes, Coraciiformes, Strigiformes, Cuculiformes, Columbiformes, Galliformes, and others, each with 1 family and 2 species.

There are 14 nationally protected Class II bird species (including the Little Swan, Mandarin Duck, Black Kite, Chinese Sparrowhawk, Common Buzzard, Eurasian Kestrel, Amur Falcon, Common Crane, Short-eared Owl, and Long-eared Owl). Additionally, there are 26 Anhui Provincial Key Protected Animal species (such as the Bean Goose, Greylag Goose, Northern Pintail, Mallard, Spot-billed Duck, Green-winged Teal, Common Pheasant, Common Quail, Eurasian Cuckoo, Oriental Cuckoo, Barn Swallow, Red-rumped Swallow, Brown Shrike, Bay-backed Shrike, Black-naped Oriole, and Slaty-backed Forktail).

III. Hydrology and Climate

Xiao County falls within the semi-humid monsoon climate zone of eastern China, characterized by distinct seasons, ample sunlight, moderate rainfall, and concurrent rain and heat. Spring is warm with rapidly rising temperatures and gradually increasing rainfall, dominated by easterly winds. Summer experiences abundant rainfall, with synchronized light, heat, and water, and prevailing southerly winds. Autumn is cool with ample sunshine, large diurnal temperature variations, and less rainfall. Winter often sees cold air intrusions, mostly clear skies, and little rainfall. The annual sunshine duration ranges from 2,220 to 2,480 hours, with an average annual temperature of 14.4°C, an average frost-free period of 208.3 days, and an average annual rainfall of 811.2 mm.