Studies of Sulphur- and Iron-induced Copper Deficiency in Tibetan Sheep

The clinical signs of Tibetan sheep with sulphur- and iron-induced copper deficiency in Maqu County of Gansu Province were defined as thin, decreased appetite, neonatal ataxia, pica, emaciation, and loss of hair color and anemia. The mineral composition of soil and forage, and samples of liver, blood and hair from Tibetan sheep in affected ranches in this region were compared with those from unaffected areas. The mean concentration of iron in soil and forage in affected pasture was 19 675 ±791 and 1 763 ±197 μg/g, respectively, compared with 8 761 ±871 and 357 ±39 μg/g in unaffected pasture. The mean concentration of sulphur in soil and forage in affected pasture was 1.98% ±0.79% and 0.88% ±0.16%, respectively, compared with 1.16%±0.26% and 0.47%±0.16%in unaffected pasture. The mean copper concentrations in soil and forage from the affected pastures were 15.9±1.8 and 6.7±1.6 μg/g, respectively, compared with 16.7±1.9 and 8.9±2.7 μg/g in unaffected pasture.The mean concentration of Cu in blood, liver, and hair from the affected Tibetan sheep were 0.32±0.12, 51.2±3.1 and 2.16±0.65μg/g, respectively, compared with 0.76±0.21, 191±11 and 3.27±0.96 μg/g for healthy animals. Oral administration of CuClO(OH)3prevented and cured anemia. We conclude that wool eating of Tibetan sheep in this region is probably caused by secondary Cu deficiency, mainly due to the high iron and sulphur contents in soils and forage.

The Relationship Between Vegetation Characteristics and Altitudes in Transitional Permafrost Zone in Xidatan, Qinghai-Tibetan Plateau

Many studies showed that permafrost has profound influence on alpine ecosystem. However, former researches were mainly focused on typical points by temporal scales. There were few studies about the correlation between vegetation characteristics and different altitudes covering a large region in spatial pattern, especially in transitional permafrost(TP). There were continuous permafrost(CP) discontinuous permafrost(DCP) and seasonal frozen ground(SFG) in this study region. The types of permafrost changed from SFG to DCP, and finally become CP as the altitudes of Xidatan increase. In this paper, 112 845 points interpreted by HJ1-B(environment and disaster monitoring and prediction small satellite constellation), vegetation investigation points, thawing layer thickness research sites, ground temperature and water content observation plots were used to examine the spatial pattern of vegetation which were located in different altitudes in Xidatan, a typical TP region, in Qinghai-Tibetan Plateau. Vegetation characteristics, soil moisture content(SMC) and thaw depths were collected in 15 August to 25 August2012. Characteristics of vegetation were mainly represented by fractional vegetation cover(FVC) derived from the normalized difference vegetation index(NDVI), as well as above ground biomass(AGB). In this paper, we analyzed that the distinction of vegetation characteristics in each range through statistics data. These ranges were divided by varied altitudes. For examples, the ranges were divided into 50 m or 100 m. In this study we use a large area plots method to further discuss the relationship between the features of vegetation and the different regions of permafrost based on altitudes shifts in Xidatan. A diagram described the vegetation characteristics variability with rising altitudes in transitional permafrost region was drawn in this paper. Our results illustrated the FVCs first increased in SFG region and then decreased in DCP zone slowly, and in CP region FVCs soared then dropped dramatically. With the altitudes increased, the curve of FVCs indicated a parabolic distribution except a little difference in the first 200 m range.

Current Distribution of Vegetation Resources in Yunnan-Guizhou Plateau and Mechanism Research of Its Effects on Rocky Desertification Process

Yunnan-Guizhou Plateau is the core area of the rocky desertification in the Chinese southwest Karst regions, and the existing studies are very limited to describe the process of rocky desertification quantitatively. The vegetation resources are applied as the key indicators in quantitative description of the degree of rocky desertification damage, and the previous methods using only remote sensing datasets are not competent to distinguish the detailed information of vegetation type, coverage and patch fragmentation on a large scale. Previous research shows that the technology of unmanned aerial vehicle and the estimation software of fraction vegetation coverages and patches could be accurately and rapidly to exploit vegetation resource information. In this project, current distribution of vegetation resources in Yunnan-Guizhou Plateau was clarified to reveal the influence mechanism of the rocky desertification. The control factors of rocky desertification distribution and the driving reasons of its dynamic changes were explained by the data of terrain, climate, population, economics and policy. Therefore, it could get the current distribution of vegetation resources in Yunnan-Guizhou Plateau, especially the grassland resources could be updated, which could not provide research foundations and scientific implications for resolving the rocky desertification, but also could provide valuable background information for the programs of restoring ecological environment and increasing local people's income in Yunnan-Guizhou Plateau.