长期模拟增温对矮嵩草草甸土壤理化性质与植物化学成分的影响  

Effects of long-term simulated warming on soil physicochemical properties and plant chemical components of Kobresia humilis meadow

作　　者：杨月娟[1,2] 周华坤[1] 姚步青[1] 王文颖[3] 董世魁[4] 余欣超 赵新全[1] 张灏[5] 

机构地区：[1]中国科学院西北高原生物研究所,西宁810008 [2]中国科学院大学,北京100049 [3]青海师范大学,西宁810008 [4]北京师范大学,北京100875 [5]山西农业大学,山西太谷030801

出　　处：《生态学杂志》2015年第3期781-789,共9页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(31172247;31201836;31472135);青海省自然科学基金项目(2013-Z-916);中国科学院战略性先导科技专项(XDA05070202);国家科技支撑专项(2011BAC09B06-02;2014BAC05B03);青海省重点实验室发展专项(2013-Z-Y07;2014-Z-Y01)资助

摘　　要：采用国际冻原计划(ITEX)长期模拟增温试验装置,研究了退化和未退化的矮嵩草草甸上植物化学成分(粗灰分、中性洗涤纤维、酸性洗涤纤维、木质素、粗脂肪、粗蛋白和无氮浸出物)含量、土壤环境因子(速效氮、速效钾、速效磷、全氮、全磷、全钾、有机质和土壤含水量)的变化及其相互关系。结果表明:长期模拟增温明显影响了土壤理化性质和3个功能群植物的化学成分含量(P<0.05);在退化的矮嵩草草甸上长期模拟增温,两者存在明显的交互效应(P<0.05),增温增加了植物可直接利用的土壤养分含量,但土壤中有机质、全氮、全磷、全钾和含水量均低于其各自对照,增温降低了优良牧草(禾草和莎草)粗脂肪、粗蛋白和无氮浸出物的含量,增加了粗灰分、中性洗涤纤维、酸性洗涤纤维和木质素含量,降低了牧草消化率;长期模拟增温条件下,土壤理化性质对植物化学成分的贡献大小依次是:速效氮>有机质>含水量>速效钾。典型对应分析表明,长期模拟增温进一步巩固了未退化矮嵩草草甸禾草类和莎草类优势牧草的地位,杂类草逐渐衰退;而在退化矮嵩草草甸样地上长期模拟增温,群落优势种的优势度下降,加剧了草地退化。By employing the long-term simulation temperature experimental test device recom- mended by the International Tundra Experiment （ITEX） , the responses of plant chemical compo- nents （crude ash, neutral detergent fiber, acid detergent fiber, lignin, crude fat, crude protein and nitrogen free extract） and soil physicochemical properties （available nitrogen, available po- tassium, available phosphorus, total nitrogen, total phosphorus, total potassium, organic matter, and moisture content） to warming on degraded and undegraded Kobresia humilis meadows were studied. The results showed that long-term simulated warming significantly affected soil physico- chemical properties, and plant chemical components of three functional groups （P〈0.05）. There were obvious interactive effects between plant chemical components and soil physieochemical properties in degraded K. humilis meadow under long-term simulated wanning （P〈 0.05 ）. The simulated warming increased soil available nutrients which could be directly used by plants, but decreased soil organic matter, total nitrogen, total phosphorus, total potassium and moisture con- tents in the degraded meadow, compared with the control. Meanwhile, warming decreased the contents of crude fat, crude protein and nitrogen free extract of high-quality herbage （ Gramineae and Cyperaceae ）, while increased the contents of some indigestible ingredients such as crude ash, neutral detergent fiber, acid detergent fiber, lignin, consequently, resulting in a decrease in ruminant assimilation ability. Under long-term simulated warming conditions, the contributions of soil environmental factors to plant chemical composition were as follows： available nitrogen 〉 organic matter 〉 moisture content 〉 available potassium. Canonical correspondence analysis showed that long-term warming further increased the advantages of Gramineae and Cyperaceae species in the non-degraded K. hurnilis meadow, while forbs gradually declined. In the degraded meadow, the dominance of d

关 键 词：长期增温 退化 功能类群 交互作用 典型对应分析 

分 类 号：Q945.79[生物学—植物学]