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Microbes remain active and play an important role in soil nitrogen (N) cycle during the winter in soil of the alpine zone
. A shift from microbial N immobilization process dominant during summer to prevailing microbial mineralization process during the winter is observed. Warmer soil under deep snow cover may increase the microbial activity and rate of organic matter decomposition over the winter. Furthermore, severe shortages of dissolved carbon (C) in the winter may cause microbial mortality and lyses. Thus, C limitation on microbial growth and activity may have an important effect on winter N mineralization and even on soil N pools. However, the combined effects of additional organic C (litter inputs) and snow cover on soil N biogeochemical processes in the Tibetan Plateau remain unclear.In the current study, the in situ effects of snowpack and litter decomposition on N dynamics in the alpine zone of the Eastern Tibetan Plateau were investigated. Intact soil core incubations in three different snow regimes (0, 30 and 100 cm depth snow) in the winter were used to solve the problem by measure concentrations of mineral form of soil N. In addition, the litter bag method was used to analyze the litter decomposition over the winter. Our results indicate that the snow cover reduced the ammonium (NH4+-N) content, accelerate N mineralization in soil, and did not significantly change the dissolvable organic nitrogen (DON) and microbial biomass nitrogen (MBN). Meanwhile, snowpack increased the litter N content and accelerated litter decomposition in late winter. Litter addition reduced the MBN and NH4+-N contents in soil, but increased the nitrate (NO3--N) content and net N mineralization, suggesting that N availability to plants during the spring thaw period may be enhanced
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The present paper analyses the changes in migration patterns of a Tibetan-style transhumance livelihood system for a period of 20 years in northwest Yunnan, China
. Between 1984 and 2005, the average number of pastures for rotational use in the 12 investigated villages decreased from 6.2 to 3.9, and the average number of stops on the annual migration route decreased from 8.3 to 5.8. The number of days during which the animals depend on stall feeding and low-elevation shrubs increased from 231.3 to 270, while those spent in forest belts decreased by 32.6% and those in alpine rangelands by 25.5%. These changes have intensified the pressure on low-elevation ecosystems and grazing resources. Winter fodder supply, rather than carrying capacity based on overall grazing resources at all elevations, should be used to determine the scale of pastoral development. Encroachment of woody plants is a major cause of alpine rangeland degradation, which used to be unjustifiably attributed to a growing livestock population. Reintroduction of traditional management tools such as burning can effectively increase the area of available rangeland resources and curb localised degradation processes by evening out grazing pressure
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Annotation :::: The paper provides gender analysis of rural migration, and examines data collected from the investigation through regression analysis to better understand migration willingness and migration intention of rural women in the urbanization process of the region
. Using the methods of documental study and a case study of the Yangtze River delta region, the paper identifies the four factors that have had a positive impact on migration willingness of rural women: age, level of education, work seniority outside of their home villages, and whether or not they have school age children. Economic considerations also remain an important factor that affects the migration decisions of women and men. Additionally, women pay more attention than men to the education of children, while men show more concern than women for self-development in the process of migration. Children’s education and self-development are the primary subjective reasons for women’s migration, while employment, business, and work transfer are the primary objective reason. Compared with migrant men, migrant women have very limited channels for seeking jobs, a narrow field for employment, and generally lower employment levels, which directly result in yearly income of women migrant being much lower than that of men migrant. Regarding the problems arising after migration, both men and women express concern about inter-personal relationships, and making a living, and children going to school and problems they may face in this regard
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