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| 1 | Seasonal variations in the Sr-Nd isotopic compositions of suspended particulate matter in the lower Changjiang River:Provenance and erosion constraints显示文摘Suspended particulate matter samples were collected monthly for more than 2 years in Nanjing,China to examine seasonal changes in the Sr-Nd isotopic compositions of the lower Changjiang River(CR).The results indicate that the 87Sr/86Sr ratios of the samples ranges from 0.725352 to 0.738128,and the values ofεNd(0)ranges from-10.55 to-12.29.The Sr-Nd isotopic compositions show distinct seasonal variations.The samples had lower 87Sr/86Sr ratios and higherε Nd(0)values during the flood season than the dry seasons.The seasonal variations primarily reflect the controls of provenance rocks and erosion in different sub-catchments.The relative decrease in 87Sr/86Sr ratios and the increase inε Nd(0)values during the flood season may reflect an increasing in the mechanical erosion rate in the upper basin and the contribution of more sediment from the upper reaches.The end member values of 87Sr/86Sr andε Nd(0)of the samples were 0.728254 and?11.26,respectively. | MAO ChangPing CHEN Jun YUAN XuYin YANG ZhongFang JI JunFeng | 2011 | Chinese Science Bulletin2011，56，22： | 7 |
| 2 | Sustainable management of Chinese grasslands—issues and knowledge显示文摘China has almost 400 Mhm^2 of grasslands,90% of which is considered degraded to varying degrees,on which 16 million herders depend for their livelihoods and many more indirectly, along the value-adding chain.Since 1950, average stocking rates across China have increased 4-fold. National policies have focused over recent decades on finding ways to rehabilitate the degraded grasslands, to sustain livestock production from them, and to improve the livelihoods of herder households, who are among the poorest people in China. A large collaborative program commenced in the early 2000 s to help find solutions to the sustainable management of grasslands.This paper summarizes key findings of many research projects, identifies where knowledge is weak and argues that the successful rehabilitation of grasslands will also require policies that provide incentives and support for herders as they move from a focus on survival to a focus on production of higher quality products, for which consumers are increasingly willing to pay. A key focus is to emphasize the improvement of animal production per head. When this is done, it naturally leads to lower stocking rates, which in turn provides the opportunities for grasslands to recover. Across a range of experiments, farm demonstrations and analyses using models, in Inner Mongolia and Gansu, a consistent result has been that a 50% reduction in stocking rates, improves net household income and starts the process of grassland rehabilitation.Rather than focusing on stocking rates, better management of grasslands could be achieved by maintaining the grasslands above critical values for herbage mass, values that help optimize botanical composition, reduce soil erosion, optimize animal growth rates and aid ecosystem functions. Managing to critical values for herbage mass is likely to be more effective than efforts to calculate sustainable stocking rates. An early summer rest is valuable for aiding grassland rehabilitation and summer productivity, but a total grazing ban(typically for 5 years)may not achieve its aims as evidence shows it may take 10–15 years to achieve a better grassland state. Lessdesirable plant species often increase in degraded grasslands that are rested and grazing can help manage those species. Surveys of herders indicate they have very mixed views on the benefits of total grazing bans that are unlikely to rehabilitate grasslands to an ideal botanical composition.The current objective is to work with grasslands that herders now have and optimize the existing composition.Grazing grasslands in winter results primarily in weight loss by animals and there is now evidence of how winter grazing reduces grassland growth in the next summer. It is better to keep animals in well-built sheds and feed them better, improved feeding through the cold months is required. In addition to the application of results from national programs designed to improve grasslands, it will be important to train herders as they move from survival to production, to foster the development of better markets for their livestock products, to devise better financial support for herder businesses and to revise land tenure arrangements so that herders can expand the area of land they graze on better terms than apply at present. | David KEMP Guodong HAN Fujiang HOU Xiangyang HOU Zhiguo LI Yi SUN Zhongwu WANG Jianping WU Xiaoqing ZHANG Yingjun ZHANG Xuyin GONG | 2018 | Frontiers of Agricultural Science and Engineering2018，5，1： | 3 |
| 3 | Precipitation and seasonality affect grazing impacts on herbage nutritive values in alpine meadows on the Qinghai-Tibet Plateau显示文摘Aims Grasslands used for animal husbandry are chosen depending on the nutritive values of dominant herbage species.However,the influence of grazing in combination with precipitation and growing season on the nutritive values of dominant species has not been explicated.Methods To unveil the influence of the different grazing intensities on the nutritional values,an ecological study was formulated,namely fencing(G0),light grazing(G1),moderate grazing(G2)and high grazing(G3).This ambitious study was undertaken on the nutritive values of the four dominant species of herbage in an alpine meadow on the Qinghai-Tibet Plateau(QTP)during growing season(June–September)for two successive years,namely 2015(rainy year)and 2016(droughty year).Important Findings We found that(i)the nutritive value of Kobresia capillifolia,Polygonum viviparum and Caragana sinica was noticeably increased by grazing,but negligible effect on Potentilla fruticosa nutritive value was recorded.(ii)During the rainy year(2015),compared with G0,Polygonum viviparum and Potentilla fruticosa displayed 5.4 and 1.5%increases in the crude protein(CP)content and 8.5 and 2.4%increases in vitro true digestibility(IVTD),respectively,while the neutral detergent fibre(NDF)decreased by 13.5 and 0.9%,respectively.During the droughty year(2016),compared with G0,C.sinica and Potentilla fruticosa showed increases in the CP content by 4.3 and 1.3%and increases in the IVTD by 10.7 and 0.4%,respectively,during G3,while the NDF decreased by 6.0 and 1.0%,respectively.(iii)The nutritive values of all species were higher in the years when the rains were good.However,the nutritive values suffered heavily during drought conditions.Besides,the highest and lowest values of nutrition were detected in June and in September,respectively.The inter-seasonal and the inter-annual changes in the nutritional values of species were higher for K.capillifolia and Polygonum viviparum than for Potentilla fruticosa and C.sinica,suggesting that Potentilla fruticosa and C.sinica had higher water-use efficiency.(iv)Grazing clearly reduced the drought tolerance of three species and showed no effects on Potentilla fruticosa.(v)Grazing clearly increased the inter-month variation in the nutritional value of K.capillifolia and Polygonum viviparum but showed no effects on Potentilla fruticosa or C.sinica.Evidently,the grazing effects impacting the nutritional value of the dominant species of herbage exhibited conspicuous inter-annual and seasonal variations with species-specific influences and responses.Our findings are expected to have far-reaching implications enabling the authorities to arrive at strategic decisions and designing of relevant policies for the efficient management of the ecosystems ensuring the speed restoration of the QTP under severe grazing and extreme climatic circumstances. | Xixi Yao Jianping Wu Xuyin Gong | 2019 | Journal of Plant Ecology2019，12，6： | 3 |
| 4 | Speciation and potential remobilization of heavy metals in sediments of the Taihu Lake, China显示文摘The species of Cu, Pb, Zn, Cd and Cr in sediments of the Taihu Lake, China, have been analyzed using the sequential chemical extraction method. Variations in the chemical fractions of these metals and their geographic distributions have also been studied. For all five metals, the residual fraction is highest but the exchangeable fraction is lowest among all the fractions. Compared to other metals, Cd has the highest percentage in the exchangeable fraction, and Cr is associated mainly with the residual fraction. Cu in the organic fraction and Pb in the Fe-Mn fraction are the important species, whereas the lowest percentages are found for Cd in the organic fraction, Cu in the Fe-Mn oxide fraction and Pb in the carbonate fraction. With respect to spatial differences, the total contents in the non-residual fractions of the metals in bay sediments are found to be higher than those in other sediments. The fractions of Cd, Cu and Cr showed significant variations in different regions. The fractions of Pb and Zn, however, did not show significant variations in spatial distribution, suggesting different amounts and different paths of anthropogenic input for the metals. Comparisons of the metal speciation indicated that Cd might be the most bioavailable metal, followed by Pb. | YUAN Xuyin DENG Xu SHEN Zhiyong GAO Yun | 2007 | Chinese Journal Of Geochemistry2007，26，4： | 2 |
| 5 | Superhydrophobic silicon surfaces with micro-nano hierarchical structure via deep reactive ion etching and galvanic etching显示文摘 | Yang He Cheng Yujiang Heng Xuyin | 2011 | Journal of Colloid and Interface Science2011，364，1： | 1 |
| 6 | Annual net input fluxes of heavy metals of the agro-ecosystem in the Yangtze River delta, China显示文摘 | Qingye Hou Zhongfang Yang Junfeng Ji Tao Yu Guoguang Chen Juan Li Xueqi Xia Ming Zhang Xuyin Yuan | 2013 | Journal of Geochemical Exploration2013，，： | 1 |
| 7 | FSH stimulates expression of the em- bryonic gene HGA2 by downregulating let -7 in normal fimbrial epithelial ceils of ovarian high - grade serous carcinomas显示文摘 | Xuyin Zhang Jingxin Ding | 2013 | Exp Therap Med2013，5，： | 1 |
| 8 | Genetic transformation of lipid transfer protein encodinggene in Phalaenopsis amabilis to enhance cold resistance 显示文摘 | QIN Xuyin L1U Yang MAO Shanjing | 2011 | Eu- phytica2011，177，1： | 1 |
| 9 | First record of Ulva californica in the mainland of China:a single alien parthenogenetic population in discontinuous distribution显示文摘Molecular investigations have raised concerns about the ecological risks of green tides caused by alien Ulva species in new habitats.The green tide-forming species U.californica Wille was generally considered to be native to North America,but new records have been widely reported in Europe,Asia,and Oceania in recent decades,indicating a strong dispersal capacity of the species.In this study,the first record of U.californica on the coastline of China's Mainland was reported,following a combined identification with multi-molecular markers and morphological characterization.It was shown that this species has a discontinuous distribution pattern along the coast of China's Mainland,with northern populations in the Yellow Sea and southern populations in the East China Sea and South China Sea.According to results of examination for life cycles and identification with mating type(MT)genetic markers,it was indicated that all U.californica samples were male gametophytes,and reproduced themselves through parthenogenesis solely.Combined with the fact that southern and northern populations are highly genetically identical,here we believed that U.californica was a recent alien species to China's Mainland with a rapid local spread.This finding provided evidences that the ability to reproduce in a variety of ways may play an important role in the spread of Ulva species,as well as essential basic data for marine risk management of green tides in China.In addition,according to the phylogeographic analysis,the possible geographical origin and global dispersal routes of U.californica were also proposed. | Xiu WEI Wenzheng LIU Xuyin LIN Qianchun LIU Peng JIANG | 2022 | Journal of Oceanology and Limnology2022，40，6： | 1 |
| 10 | Contamination and bioavailability of heavy metals in sediments from the Yangtze River Delta Region显示文摘 | Xuyin YUAN Xu DENG Zhiyong SHEN Bing LIU Ying CHEN | 2006 | Chinese Journal Of Geochemistry2006，25，B08： | 0 |
| 11 | Characteristics of trace elements in contaminated rivers and their environmental significance显示文摘 | Xuyin YUAN Zhiyong SHEN Xu DENG Yun GAO | 2006 | Chinese Journal Of Geochemistry2006，25，B08： | 0 |
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