不同生态治理措施下高寒沙化草地土壤氮素变化特征

发布时间：2018-04-29 04:39

本文选题：生态治理 + 植被恢复　；参考：《草业学报》2016年07期

【摘要】：草地沙化是我国最严重的生态环境问题之一。为研究不同生态治理措施对川西北高寒半湿润地区沙化草地土壤氮素的影响,本研究以围栏禁牧布设沙障燕麦和草种混播(YMCD)、围栏禁牧布设沙障播撒草种(RGCD)和围栏禁牧布设沙障自然恢复(WLCD)3种沙化草地治理措施为对象,以未修复沙化草地(CK)为对照,研究了沙化草地生态修复过程中0~60cm土层土壤氮素的变化特征。结果表明,生态修复3年后,YMCD、RGCD、WLCD 3种治理措施均显著促进地表植被的恢复、土壤物理性质的改善和氮素的积累。其中,YMCD治理措施效果最为显著,其次是RGCD,WLCD效果相对较小。土壤氮素增加幅度呈现出微生物量氮(MBN)硝态氮(NO_3~--N)铵态氮(NH_4~+-N)碱解氮(AN)全氮(TN)特征。与未修复沙化草地相比,YMCD沙地草地地表植被覆盖度增加至74.1%,土壤容重从1.45g/cm~3下降至1.39g/cm~3,夏季地表午温从41.5℃下降至23.0℃;TN、AN、NH4+-N、NO_3~--N和MBN含量分别增加了255.8%,270.2%,299.5%,357.8%和745.9%。相关性分析表明地表植被盖度和土壤容重对沙化土壤氮素含量有显著影响。
[Abstract]:Grassland desertification is one of the most serious ecological environment problems in China. In order to study the effects of different ecological treatment measures on soil nitrogen in sandy grassland of high and cold and semi humid areas in northwestern Sichuan, this study sets up sand barrier oat and grass seed mixed sowing (YMCD), fence grazing, sand barrier sowing grass (RGCD) and fence grazing to set sand barrier nature. To restore (WLCD) 3 kinds of Desertification Grassland treatment measures, the change characteristics of nitrogen in the soil layer of 0~60cm soil in the process of ecological restoration of sandy grassland were studied with the control of CK. The results showed that after 3 years of ecological restoration, the 3 treatments of YMCD, RGCD and WLCD all significantly promoted the restoration of the surface vegetation and the improvement of soil physical properties. And nitrogen accumulation. Among them, the effect of YMCD treatment is the most significant, followed by RGCD, WLCD effect is relatively small. The increase of soil nitrogen (MBN) nitrogen (MBN) nitrate nitrogen (NO_3~--N) ammonium nitrogen (NH_4~+-N) nitrogen (AN) total nitrogen (TN) characteristics. Compared with the unrepaired sandy grassland, the surface vegetation coverage in the desert grassland increased to 74. 1%, soil bulk density decreased from 1.45g/cm~3 to 1.39g/cm~3, and the meridian temperature dropped from 41.5 to 23 C in summer, and the content of TN, AN, NH4+-N, NO_3~--N and MBN increased by 255.8%, 270.2%, 299.5%, 357.8% and 745.9%. showed that the vegetation coverage and soil bulk density had significant influence on the nitrogen content in the sandy soil.

【作者单位】：四川农业大学资源学院;开江县国土资源局;
【基金】：国家支撑计划项目(2015BAC05B00) 四川省科技计划项目(2013SZ0110,2014SZ0057,2014SZ0159)资助
【分类号】：S812.2

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