Research On Seasonal Changes Of Trace Elements Of The Przewalski's Gazelle And The Habitat In Qinhai Hudong Area

As a rare, endangered and endemic species in China, Przewalski's gazelle (Procapra przewalskii)once distributed in Inner Mongolia, Gansu, Ningxia and Qinghai. The gazelles are now only living around the Qinghai Lake. Qinhai Hudong is the main habitat of the Przewalski's gazelle. In recent year, due to the various natural factors such as globle climate warming and human sufferings such as unreasonably grazing, setting fence and illegally hunting and competition from sheep and yaks and infringement natural enemies, Przewalski's gazelle's habitat is continuously worsening, Przewalski's gazelle population is continuously reduced. In fact, Qinghai Hudong is the most area for Przewalski's gazelle. This paper studied the trace elements of Przewalski's gazelle and the habitat in Qinhai Hudong in different seasons. After microwave digesting, all samples including Przewalski's gazelle's blood and hair (mid-December) and water, soil and forage from summer(mid-June), autumn(mid-September)and winter (mid-December) were determined and analyzed by Inductively Coupled Plasma Atomic Emission Spectrometry, ICP-AES and atomic fluorescence spectrometry(used to determined Se) to obtain copper, manganese, iron, zinc, molybdenum and selenium. Different pasture types were analyzed by Fisher discriminant function. All these methods were measured in order to investigate and evaluate Przewalski's gazelle's microelement nutrition. This paper provided feasible scientific measures for wetland eco-environmental construction and Przewalski's gazelle populations' protection. The results are as follows.1. There was an obvious seasonal difference between the six trace elements Cu, Fe, Mn, Zn, Mo of water in the habitat of the Przewalski's gazelle, and the change trends was different, including the highest Fe content in summer 0.039±0.007 mg / L, the highest content in autumn was 0.08mg / L, and it was still 0.054±0.009 mg / L in winter, generally, the content of six kinds of trace elements in water was very low.2. The soil of the habitat of the Przewalski's gazelle was at a low Cu, low-Mo, low-Se state. The Cu content was in the highest in summer and lowest in winter,which changed between 8.86～17.24mg/kg; Mo content varied between 0.054～0.181mg/kg, of which 0～10cm, 20～30cm soil layer in the deposition of Mo was higher than in 10～20cm,and the Mo content of the soil in three seasons are lower than the China's average level of Mo in soil 1.7mg/kg; Se content was 0.02～0.178mg/kg, a serious shortage in summer, winter is the critical lack of Se, and Se content of the soil was in normal in autumn.3. The mixed forage trace elements content in underground sections was higher than it in the ground part in summer in Przewalski 's gazelle habitat. The trace elements Cu, Mo, Se was lacking in each season, and Fe, Mn, Zn content was normal. In different seasons, the seasonal variation of trace elements which in the ground parts of mixed forage was in different, Mo content had little change in different seasons, the content of Cu, Fe, Mn, Zn was higer in summer than it in autumn and was lowest in winter, while the Se content increased with the season gradually.4. Przewalski's gazelle choosed the Achnatherum splendens grassland as its foraging habitat which had a high abundant degree, good concealment condition and little diturbing from mankind.5. The main forge of Przewalski's gazelle was low Cu, low Mo, and low Se, and its favorite forage Astragalus membranaceus was high Se plant.6. According to the blood and hair sample, some of Przewaiski's gazelles may be affected by an ailment characterized anemia for Cu deficiency or may be caused low reproductive rate for Cu and Zn deficiency. Przewalski's gazelle was low Se nutrition.7. The Fisher linear discriminant model of different seasons and different grassland types had high accuracy and credibility, which established the science basic to study the trace element changemet of different grassland types in Hudong area.For increasing Przewaiski's gazelle's habitant and more food, Achnatherum splendens should be reseeded in degradation grassland and Astragalus membranaceus should be increased to achieve proper Se nutrition. In summer molybdenum fertilizer should be added in soil to make sure Cu:Mo equal 6～10:1.