| As one of the most representative fish in Guangdong Province, White Cloud Mountain minnow(Tanichthys albonubes)has been listed in the second class state protected animals in China, and its status is extinct in nature in the China red data book of endangered animals. In 2003, the natural population of T. albonubes were rediscovered in CongHua city.Under the cooperation of the Administration Bureau of Shimen National Forest Park, a field survey was carried out that how the habitat of its natural population of Shimen National Forest Park, respectively from April in 2009 to March in 2010.Of the water quality of the park, plankton, the plant community composition around water, ecological habits and distribution pattern of T. albonubes,the relationship between influencing factors such as habitat, elevation etc. the predators and competitive species of of its and the relationship between feeding habits and larval fish environment. The main results are as follows.The T. albonubes in the 25.94mm-31.81mm long range, the average weight of 0. 179g. In addition to individual points, all samples of fish year-round distribution of the its; which in August the largest number, and in February the least; the annual distribution of the T. albonubes that shows each sample online has its habitat, including 3#,4#,7#,9#,10# and 11#, covering all kind of sample lines,.3# and 7# are the main habitat for juvenile fish Tang, the two places have in common is the water calm, rich in plants, low water depth and stability.There were three type of habitat of T. albonubes in natural distributions of Shimen National Forest Park, including U-type river,mud-sand-bottom stream and sand-stone-bottom stream. The characteristics of habitat are asfollows:1. It mainly lived in stream and marsh, sometimes its in streams downstream of the large surface on the edge;2. There are much aquatic plant in its habitat, sand-stone-bottom there are more leaves;3. Other fish are seldom in its habitat. No other fish appear in marsh, only several fish appear instream, such as Puntius semifasciolatus.4. Water temperature, water quality constant. Temperature between 22℃at 14℃.The T. albonubes distribution of the minimum altitude of 282m, up to 848m, the 280m and 800m intervals around the main distribution range around the region; Its depth distribution of not more than 0.7m, while the waters of variable width, is 0.4m～6.5m. Elevation, water width, water velocity and intensity of human disturbance affecting the T. albonubes habitat major factor, of which the water velocity and human disturbance to a separate embodiment of the habitat selection of; the depth of the riverbed composition on the T. albonubes habitat selection did not affect Great. Its habitat selection affected by pH, and nitrate, indicating that low levels of water pollution is a suitable habitat of it.Research in memory in the T. albonubes predators, including birds, fish, amphibians 14 species, seven for its main natural enemies, mainly birds, snakes, etc. the number of natural enemies directly affects the its population. Also found in competition relations between the T. albonubes and other species, in the same waters of protected areas, when the Cirrhinus molitorella, Cobitis sinensis number is higher, fewer fishes.Human activities on the impact of the T. albonubes caught mainly refers to man-made, power generation and water pollution. Storage water of power station, due to the dam to intercept, leading to the lower reaches of it can not swim well, so they can live in the upper stream only; when Station Drainage, due to higher flow rate, part of it taken by water downstream, thereby changing the location of it. When the water is contaminated, or contaminants to migrate its poison, thus changing the location and quantity of it.T. albonubes habitat and water quality and vegetation composition on the influential role, juveniles prefer quiet waters and a water plant distribution, low oxygen content. Suitable for other small zooplankton rotifer reproduction. And because adult fish larger zooplankton preference, the preference distribution in the high oxygen content and water satisfy some Cladocera breeding waters.In addition, our research showed that the decrease of habitat was negative to the natural resourceof T. albonubes, protecting the habitat of it was the most effective method.
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