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Copyright of Journal of Modern Medicine & Health is the property of Journal of Modern Medicine & Health and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The form and available state of elements are important indexes to evaluate the activity of elements. Research on the relationship between the available state and form of selenium (Se) and zinc (Zn) in farmland soil is an important basis for accurate land quality evaluation. In this paper, the available states and different forms of Se and Zn in the soil of high Se background area in Luoyang farmland were studied. The results show that the available Se in wheat soil can be replaced by the sum of water-soluble state, ion state and carbonate state. The available Se in the soil of corn, millet, sesame, peanut and sweet potato can be replaced by the sum of water-soluble state and ion state. Available Zn can be represented by the sum of water-soluble, ionic and carbonate states. The active Zn in the farmland soil developed in the basalt area was low and similar to the water-soluble Zn. The available state and forms of Se and Zn in farmland soil were mainly affected by total amount, but also by cultivated crops, pH and organic matter. It is necessary to consider agricultural planting, pH and organic matter to evaluate the availability of Se and Zn by using the form instead of the available state in farmland soil. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Agrometeorology is the property of Editorial Board of Chinese Journal of Agrometeorology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The daily meteorological variables observed at weather stations in the Qiangtang Nature Reserve of Tibet (QNRT), including average temperature, precipitation, and sunshine duration from 1971 to 2019, were analyzed with the criteria on the 5 °C threshold temperature. Based on the variation characteristics of the green grass seasons(GGS) of alpine grasslands and their hydrothermal climate conditions in the recent 49 years were revealed with the support of the statistical analyses of the linear regression, the Mann-Kendall test method and the R/S method. In addition, the possible changes of the GGS were also assessed under RCP2.6, RCP4.5 and RCP& 5 emission scenarios, in order to well understand and accurately predict the dynamic change of the terrestrial ecosystems in the future. The study results indicate that the start date of GGS has been advanced at a rate of 2.81d-10y-1 while the end date has been delayed with a rate of 2.74d-10y-1, which has contributed to an increase in duration by 5.56 days per decade. The increasing trends in cumulative temperature, precipitation, and sunshine duration were significant, with the rates of 75.860 d-10y-15 15.84mm-10y-1 and 27.58h-10y-15 respectively. In terms of the decadal variation characteristics, the start dates were late while the end dates were early at all stations from 1970s to 1990s, leading to the shorter duration of GGS and the unfavorable hydrothermal conditions. In contrast, the start dates were early while the end dates were late at all stations from 2000s to 2010s, which contributed to the longer duration of GGS and the abundant hydrothermal resource. It was detected by M-K methods that the abrupt changes of start date, end date, and duration of GGS occurred in 2006, 1991, and 1988, respectively. In addition, the abrupt increases in cumulative temperature, precipitation, and sunshine duration of GGS were also detected in 1988, 1999, and 1981, respectively. All values of H were larger than 0.5, indicating that the trends in early start date, late end date, longer duration will continue, and the increases in cumulative temperature, precipitation, and sunshine duration will remain unchanged in the future. Under RCP4.5 emission scenario, the start date of GGS will be advanced by 10 days, while the end date will be delayed by 9 days, and the duration of GGS will prolonged by 17 days in QNRT in the next 80 years, which will be beneficial to pasture growth and livestock fattening, and also play a positive role in pasture production and restoration of the grassland ecosystem in this highland region. [ABSTRACT FROM AUTHOR]

This paper is based on the meteorological observation data of the five meteorological stations (Shiquanhe, Gerze, Xianza, Bangoin and Amdo) near Qiangtang National Nature Reserve, the climate of Qiangtang National Nature Reserve from 1960 to 1990 and the estimated grid data in the future issued by IPCC5. The Miami model, Thornthwaite Memorial model, and tendency rate were used. The statistical analysis methods were used to study the spatiotemporal evolution of Net Primary Productivity in Qiangtang National Nature Reserve and its response to climate change. The results showed that: (1) the average annual temperature decreases from the west to the east, and the annual precipitation increases from the west to the east. The annual mean temperature(T) showed a significant increasing trend, while the annual precipitation(R) and annual evapotranspiration(E) showed a slight increasing trend. NPP of Temperature(NPPt) and NPP of precipitation(NPPr) showed a slight increasing trend at all stations, and NPP of evapotranspiration(NPPe) and standard NPP(NPPb) showed a slight increasing trend at most stations. (2) NPPt gradually decreased from the west to the east, NPPr gradually increased from the west to the east, NPPe and NPPb first increased and then decreased from the west to the east. The limiting factor of NPP was precipitation in Shiquanhe station and Gerze station, evapotranspiration in Xianza station and Bangoin station, and evapotranspiration or air temperature in Amdo station. (3) The NPPt, NPPr, NPPe and NPPb in different periods of the 21st century were significantly higher than those in all periods of the 20th century. The NPPt, NPPr, NPPe and NPPb were significantly increased in the future under different emission scenarios compared with those from 1960 to 1990. Under the trend of "warming and wetness" in the past 48 years and in the future, the NPP of vegetation increased, and the increase was larger in the cold and humid area in the southeast, but less in the cold and arid area in the northwest. The future climate is conducive to the improvement of local vegetation NPP and the improvement of local ecological environment. Assessing the possible impact of future climate change on the ecological environment of Qiangtang Plateau. The results not only provide a basic method for studying the Net Primary Productivity of vegetation in no man's land at regional scale, but also have important reference value for estimating ecological security research and ecological function planning. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)