黄河流域是中国“一带一路”发展的重要经济廊道,维持黄河流域的生态健康对中国经济社会发展和生态安全具有十分重要的作用。受气候变化和人类活动的影响,黄河流域出现上游植被退化、中游水沙锐减、下游用水紧张、河口三角洲退缩等生态...黄河流域是中国“一带一路”发展的重要经济廊道,维持黄河流域的生态健康对中国经济社会发展和生态安全具有十分重要的作用。受气候变化和人类活动的影响,黄河流域出现上游植被退化、中游水沙锐减、下游用水紧张、河口三角洲退缩等生态危机,严重制约了流域内的生态文明进程和经济高质量发展。以1990—2020年间Web of Science数据库中收录的5190篇相关文献和145781条参考文献为研究样本,采用可视化知识网络分析和科学计量法,从文献产出规律、关键词共现网络和未来发展方向3个方面,多角度、深层次、定量化、可视化分析黄河流域生态水文研究现状、研究机构、载文期刊、高产作者和热点研究主题。展开更多
土壤微生物在维持和提高高寒草地植被生产力水平、改善土壤环境等方面起着重要作用,基于连续2年(2014和2015年)的小区施肥控制试验,探讨高寒草原土壤剖面微生物量碳、氮对氮、磷肥添加的响应。结果如下。1)施用无机氮、磷肥对土壤微生...土壤微生物在维持和提高高寒草地植被生产力水平、改善土壤环境等方面起着重要作用,基于连续2年(2014和2015年)的小区施肥控制试验,探讨高寒草原土壤剖面微生物量碳、氮对氮、磷肥添加的响应。结果如下。1)施用无机氮、磷肥对土壤微生物量碳的影响主要表现在0~10 cm土层,其均值分别是10~20 cm和20~30 cm土层的1.67倍和1.28倍。2)单施高量氮肥显著降低土壤微生物量碳、氮含量,N_2P_0(15 g N/m^2,0 g P_2O_5/m^2)处理0~10 cm和10~20 cm土层的微生物量碳分别比空白处理显著降低60.39%和29.2%;在施磷肥的基础上增施氮肥提高土壤微生物量碳、氮含量,当施磷30 g P_2O_5/m^2时,施氮15 g N/m^2处理0~10 cm土层微生物量碳比不施氮处理增加61.54%,差异显著。3)单施磷肥各土层微生物量碳、氮含量相对于空白均无显著差异;在施氮15 g N/m^2的基础上增施15和30 g P_2O_5/m^2磷肥,0~10 cm土层微生物量碳含量比不施磷处理分别显著增加159.8%和279.98%,10~20 cm土层微生物量氮含量分别显著增加53.78%和38.66%;施磷7.5 g P_2O_5/m^2时,10~20cm土层微生物量氮含量比不施磷处理显著增加68.35%。展开更多
In the context of climate change, precipitation is predicted to become more intense at the global scale. Such change may alter soil microbial communities and the microbially mediated carbon and nitrogen dynamics. In t...In the context of climate change, precipitation is predicted to become more intense at the global scale. Such change may alter soil microbial communities and the microbially mediated carbon and nitrogen dynamics. In this study, we experimentally repackaged precipitation patterns during the growing season(from June to September) of 2012 in a semi-arid temperate steppe of the Xilin River Basin in Inner Mongolia of China, based on the 60-year growing season precipitation data. Specifically, a total amount of 240 mm simulated precipitation was assigned to experimental plots by taking the following treatments:(1) P6(6 extreme precipitation events, near the 1^(st) percentile);(2) P10(10 extreme precipitation events, near the 5^(th) percentile);(3) P16(16 moderate precipitation events, near the 50^(th) percentile); and(4) P24(24 events, 60-year average precipitation, near the 50^(th) percentile). At the end of the growing season, we analyzed soil microbial community structure and biomass, bacterial abundance, fungal abundance and bacterial composition, by using phospholipid fatty acid(PLFA), real-time quantitative polymerase chain reaction(RT-qPCR) and 16S rRNA gene clone library methods. The extreme precipitation events did not change soil microbial community structure(represented by the ratio of PLFA concentration in fungi to PLFA concentration in bacteria, and the ratio of PLFA concentration in gram-positive bacterial biomass to PLFA concentration in gram-negative bacterial biomass). However, the extreme precipitation events significantly increased soil microbial activity(represented by soil microbial biomass nitrogen and soil bacterial 16S rRNA gene copy numbers). Soil fungal community showed no significant response to precipitation events. According to the redundancy analysis, both soil microbial biomass nitrogen and soil ammonium nitrogen(NH_4-N) were found to be significant in shaping soil microbial community. Acidobacteria, Actinobacteria and Proteobacteria were the dominant phyla in soil bacterial composition, and responded differently to the extreme precipitation events. Based on the results, we concluded that the extreme precipitation events altered the overall soil microbial activity, but did not impact how the processes would occur, since soil microbial community structure remained unchanged.展开更多
文摘黄河流域是中国“一带一路”发展的重要经济廊道,维持黄河流域的生态健康对中国经济社会发展和生态安全具有十分重要的作用。受气候变化和人类活动的影响,黄河流域出现上游植被退化、中游水沙锐减、下游用水紧张、河口三角洲退缩等生态危机,严重制约了流域内的生态文明进程和经济高质量发展。以1990—2020年间Web of Science数据库中收录的5190篇相关文献和145781条参考文献为研究样本,采用可视化知识网络分析和科学计量法,从文献产出规律、关键词共现网络和未来发展方向3个方面,多角度、深层次、定量化、可视化分析黄河流域生态水文研究现状、研究机构、载文期刊、高产作者和热点研究主题。
文摘土壤微生物在维持和提高高寒草地植被生产力水平、改善土壤环境等方面起着重要作用,基于连续2年(2014和2015年)的小区施肥控制试验,探讨高寒草原土壤剖面微生物量碳、氮对氮、磷肥添加的响应。结果如下。1)施用无机氮、磷肥对土壤微生物量碳的影响主要表现在0~10 cm土层,其均值分别是10~20 cm和20~30 cm土层的1.67倍和1.28倍。2)单施高量氮肥显著降低土壤微生物量碳、氮含量,N_2P_0(15 g N/m^2,0 g P_2O_5/m^2)处理0~10 cm和10~20 cm土层的微生物量碳分别比空白处理显著降低60.39%和29.2%;在施磷肥的基础上增施氮肥提高土壤微生物量碳、氮含量,当施磷30 g P_2O_5/m^2时,施氮15 g N/m^2处理0~10 cm土层微生物量碳比不施氮处理增加61.54%,差异显著。3)单施磷肥各土层微生物量碳、氮含量相对于空白均无显著差异;在施氮15 g N/m^2的基础上增施15和30 g P_2O_5/m^2磷肥,0~10 cm土层微生物量碳含量比不施磷处理分别显著增加159.8%和279.98%,10~20 cm土层微生物量氮含量分别显著增加53.78%和38.66%;施磷7.5 g P_2O_5/m^2时,10~20cm土层微生物量氮含量比不施磷处理显著增加68.35%。
基金financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA19030202)the International Cooperation and Exchange of National Natural Science Foundation of China (31761123001, 31761143018)
文摘In the context of climate change, precipitation is predicted to become more intense at the global scale. Such change may alter soil microbial communities and the microbially mediated carbon and nitrogen dynamics. In this study, we experimentally repackaged precipitation patterns during the growing season(from June to September) of 2012 in a semi-arid temperate steppe of the Xilin River Basin in Inner Mongolia of China, based on the 60-year growing season precipitation data. Specifically, a total amount of 240 mm simulated precipitation was assigned to experimental plots by taking the following treatments:(1) P6(6 extreme precipitation events, near the 1^(st) percentile);(2) P10(10 extreme precipitation events, near the 5^(th) percentile);(3) P16(16 moderate precipitation events, near the 50^(th) percentile); and(4) P24(24 events, 60-year average precipitation, near the 50^(th) percentile). At the end of the growing season, we analyzed soil microbial community structure and biomass, bacterial abundance, fungal abundance and bacterial composition, by using phospholipid fatty acid(PLFA), real-time quantitative polymerase chain reaction(RT-qPCR) and 16S rRNA gene clone library methods. The extreme precipitation events did not change soil microbial community structure(represented by the ratio of PLFA concentration in fungi to PLFA concentration in bacteria, and the ratio of PLFA concentration in gram-positive bacterial biomass to PLFA concentration in gram-negative bacterial biomass). However, the extreme precipitation events significantly increased soil microbial activity(represented by soil microbial biomass nitrogen and soil bacterial 16S rRNA gene copy numbers). Soil fungal community showed no significant response to precipitation events. According to the redundancy analysis, both soil microbial biomass nitrogen and soil ammonium nitrogen(NH_4-N) were found to be significant in shaping soil microbial community. Acidobacteria, Actinobacteria and Proteobacteria were the dominant phyla in soil bacterial composition, and responded differently to the extreme precipitation events. Based on the results, we concluded that the extreme precipitation events altered the overall soil microbial activity, but did not impact how the processes would occur, since soil microbial community structure remained unchanged.
