青藏高原高寒草甸土壤物理性质及碳组分对增温和降水改变的响应

发布时间：2018-11-19 08:00

【摘要】：自2011年起,在青藏高原高寒草甸实施人工模拟增温和降水改变实验,2013年7月采集实验区土壤样品,监测土壤物理特性(土壤粒径和pH值)以及碳组分(全碳、有机碳、可提取有机碳、微生物生物量碳)的变化,得到如下结果。1)增温显著改变0~20 cm土壤温度和含水量,增水和减水显著提高和降低0~20 cm土壤含水量,但不影响土壤温度。2)在0~10 cm土层深度,增温显著降低土壤微生物生物量碳;增水降低土壤可提取有机碳含量,增加土壤微生物生物量碳;减水显著增加土壤黏粒比例和可提取有机碳含量,降低土壤砂粒比例和微生物生物量碳。在10~20 cm土层深度,增水显著降低土壤可提取有机碳含量。3)增温和降水改变对土壤测定指标的影响不存在交互作用。4)主成分分析结果表明,土壤总体格局发生趋同主要是因为降水改变,而不是增温。结果表明,在未来青藏高原高寒草甸降水持续增加的情景下,土壤黏粒比例和可提取有机碳含量的降低可能会进一步对高寒地区的植物生产力以及微生物群落产生重要影响。
[Abstract]:Since 2011, artificial simulated warming and precipitation change experiments have been carried out in alpine meadow of Qinghai-Tibet Plateau. Soil samples were collected in July 2013 to monitor soil physical properties (soil particle size and pH value) and carbon components (total carbon, organic carbon). The changes of organic carbon and microbial biomass carbon were obtained. 1) the temperature and water content of 0 ~ 20 cm soil were significantly changed by increasing temperature, and the soil water content of 0 ~ 20 cm was significantly increased and decreased by increasing water and reducing water. But it did not affect the soil temperature. 2) at the depth of 0 ~ 10 cm, the soil microbial biomass carbon was significantly decreased by increasing soil temperature. Increasing water can reduce soil organic carbon content and increase soil microbial biomass carbon, and water reduction can significantly increase soil clay ratio and extractable organic carbon content, and decrease soil sand content and microbial biomass carbon content. At the depth of 10 ~ 20 cm soil layer, increasing water significantly decreased the content of extractable organic carbon in soil. 3) there was no interaction between the changes of temperature and precipitation on the soil index. 4) the results of principal component analysis showed that there was no interaction between soil organic carbon content and soil organic carbon content. The general pattern of soil converges mainly because of the change of precipitation rather than the increase of temperature. The results show that the decrease of soil clay ratio and extractable organic carbon content may further affect plant productivity and microbial community in the alpine region under the situation of continuous increase of precipitation in alpine meadow over the Qinghai-Xizang Plateau in the future.
【作者单位】：地表过程分析与模拟教育部重点实验室北京大学城市与环境学院生态学系;高原生物进化与适应重点实验室中国科学院西北高原生物研究所;
【基金】：973计划重大科学研究计划项目(2014CB954003,2014CB954004)资助
【分类号】：S812.2

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