喷灌对藏北高寒草地生产力和物种多样性的影响

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 喷灌对藏北高寒草地生产力和物种多样性的影响 DOI: 10.5846/stxb201403310599 作者: 作者单位: 中国农业科学院农业环境与可持续发展研究所／农业部农业环境与气候变化重点实验室,北京市园林科学研究院,中国建筑设计咨询公司绿色建筑设计研究院／中国建筑设计研究院建筑节能与新能源工程中心,中国农业科学院农业环境与可持续发展研究所／农业部农业环境与气候变化重点实验室,中国农业科学院农业环境与可持续发展研究所／农业部农业环境与气候变化重点实验室,中国农业科学院农业环境与可持续发展研究所／农业部农业环境与气候变化重点实验室,西藏自治区那曲地区草原站,西藏自治区那曲地区草原站,西藏自治区那曲地区草原站 作者简介: 通讯作者: 中图分类号: 基金项目: 国家科技支撑课题(2012BAC01B02);国家自然科学基金项目(31170460);西藏那曲地区与中国农业科学院合作项目 Effects of irrigation on alpine grassland Northern Tibet Author: Affiliation: Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences/ Key Laboratory for Agro-Environment Climate Change,Ministry of Agriculture,Beijing Institute of Landscape architecture,China Building Design Consultants COCBDC/China Architecture design Research Group CAG,Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences/ Key Laboratory for Agro-Environment Climate Change,Ministry of Agriculture,Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences/ Key Laboratory for Agro-Environment Climate Change,Ministry of Agriculture,Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences/ Key Laboratory for Agro-Environment Climate Change,Ministry of Agriculture,Nagqu grassland station,Tibet Autonomous Region,Nagqu,Nagqu grassland station,Tibet Autonomous Region,Nagqu,Nagqu grassland station,Tibet Autonomous Region,Nagqu Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:通过3a(2008-2010年)的藏北高寒草地喷灌试验,研究了不同喷灌量对草地群落生产力和物种多样性的影响.结果表明,丰水年灌溉对藏北高寒草地的影响较小;而在相对干旱年份灌溉对高寒草地生产力和物种多样性影响显著.喷灌条件下高寒草地生物量显著提高,最高增幅出现在高水(GS)样地中,达到116%.喷灌明显促进物种重要值提高,其中灌木和阔叶杂草比例增加趋势更为明显.不同喷灌条件下优势物种相对重要值均有不同程度的降低,高水处理降低幅度最大.物种多样性方面,喷灌措施能够明显促进高寒草地Simpson指数和Shannon-weiner指数增加(P < 0.05),E. Pielou均匀度指数无显著变化(P > 0.05).Shannon-weiner指数与生物量之间存在显著正相关关系(P < 0.05).未来降水增多的气候条件可以减少干旱对高寒草地带来的负面影响,有利于提高草地生产力和维持草地物种多样性,促进高寒草地畜牧业健康发展. Abstract:Productivity and species diversity are important indicators of the service functions and basic factors of stability in grassland ecosystems. Precipitation is a main limiting factor of grassland productivity. There is a positive correlation between precipitation and productivity. Species diversity increases under precipitation enhancement; the water availability of the plant community has an important effect on community structure, composition, and species diversity. An increase in soil moisture content not only affects the grassland plant communities directly but also improves soil nutrient availability to promote plant growth. However, drought could lead to a series of negative effects on grassland ecosystems. Therefore, moisture is an important factor for productivity and species diversity, and it even affects the stability and sustainability of grassland ecosystems.Northern Tibet has low ecosystem stability, so external disturbances, such as climate change and human activities, easily result in variation in the pattern, process, and function of ecosystems. In recent years, Northern Tibet has experienced warming and increased precipitation. Increased precipitation will affect grassland productivity and species diversity, and will even influence animal husbandry. As a main measure of the adaptation strategy for climate change, irrigation could be a reasonable pathway to redistribute and make full use of increased precipitation.In this study, we conducted a growing season irrigation experiment in Northern Tibet (between 2008 and 2010) to simulate the precipitation enhancement in this area. We designed 4 irrigation gradients: CK (no irrigation), DS (low irrigation, plus 5% more than the ambient precipitation), ZS (moderate irrigation, plus 10% more than the ambient precipitation), and GS (high irrigation, plus 15% more than the ambient precipitation). We measured plant biomass, community composition, and species diversity under different amounts of irrigation. The results showed that irrigation had greater effects on alpine grassland productivity and species diversity in drought years than in wet years. Under the irrigation conditions, the grassland biomass increased significantly, and the highest increase was up to 116% in a high irrigation plot. Irrigation promoted the species importance values of alpine grasslands; in particular, the proportion of shrubs and broad-leaved forbs was increased. The proportion of dominant species decreased significantly under irrigation conditions, and the decrease was the highest in the high irrigation plot. The Simpson index and Shannon-Wiener index significantly increased under different amounts of irrigation (P < 0.05). The E. Pielou evenness index was not significantly influenced by irrigation (P > 0.05). There was a positive correlation between biomass and the Shannon-Wiener index (P < 0.05). In short, we can project that grassland biomass and species diversity will increase under future precipitation enhancement; this will reduce the negative impact of drought in alpine grasslands and promote the sustainable development of animal husbandry in alpine grasslands. 参考文献 相似文献 引证文献