长期施肥和增水对半干旱草地土壤性质和植物性状的影响  

Effects of long-term fertilization and water addition on soil properties and plant community characteristics in a semiarid grassland

作　　者：姜勇[1] 徐柱文[1,2] 王汝振 李慧 张玉革[3] JIANG Yong;XU Zhu-wen;WANG Ru-zhen;LI Hui;ZHANG Yu-ge(Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China;School of Ecology and Environment,Inner Mongolia University,Hohhot 010021,China;College of Environment,Shenyang University,Shenyang 110044,China)

机构地区：[1]中国科学院沈阳应用生态研究所,沈阳110016 [2]内蒙古大学生态与环境学院,呼和浩特010021 [3]沈阳大学环境学院,沈阳110044

出　　处：《应用生态学报》2019年第7期2470-2480,共11页Chinese Journal of Applied Ecology

基　　金：国家重点研发计划项目(2016YFC0500707);国家自然科学基金项目(31870441,31770525,41371251,31370009,31300387,31000200);国家重点基础研究发展计划项目(2011CB403204)资助~~

摘　　要：本文对内蒙古多伦退化草地2005年建立的长期野外控制试验中施肥和增水对土壤性质和植物群落特征的影响进行了总结和综合评述.结果表明:加氮导致了表土酸化并降低酸缓冲容量,提高了表土中碳氮磷硫有效性及DTPA-浸提态铁锰铜含量,导致盐基离子钙镁钾钠总量的消耗,降低了土壤微生物群落多样性,促进了优势植物物种叶片对氮磷硫钾及锰铜锌的吸收,抑制植物叶片对铁的吸收,而对钙镁吸收无显著影响,增加了植物地上净初级生产力(ANPP),降低了植物物种多样性和群落稳定性.单独加磷增加了表土全磷和Olsen-P含量及真菌丰度,促进了植物叶片对氮、磷、硫的吸收,但对其他土壤基本化学性质及ANPP、物种多样性无显著影响.增水提高了植物群落对干旱的抵抗力,但对ANPP增长的贡献受到土壤氮有效性的限制.增水对于加氮导致的土壤酸化、植物和微生物多样性降低等具有一定的缓冲作用;加氮增水和加磷增水下,土壤微生物多样性及功能受地上植物群落结构及功能变化的影响.长期野外控制试验对于深入理解草地生态系统结构和功能对环境变化的响应具有重要意义,但单点的研究结果仍需与不同区域多点控制试验的联网研究相结合,深入开展地上与地下生态过程的关联研究,才能深入理解草地生态系统生态学的相关机制.We summarized the effects of fertilization and water addition on some soil properties and plant community characteristics in a long-term field experiment established in 2005 in a degraded grassland in Duolun, Inner Mongolia, China. The results showed that nitrogen(N) addition resulted in surface soil acidification and decreased acid buffering capacity, increased the availability of carbon(C), N, phosphorus(P), sulfur(S) and DTPA-extractable iron(Fe), manganese(Mn), and copper(Cu) contents, depleted the sum of base cations calcium(Ca), magnesium(Mg), potassium(K) and sodium(Na), decreased the diversity of soil microbial community. Nitrogen addition enhanced the uptake of N, P, S, K, Mn, Cu and Zn by plants, while inhibited plant Fe uptake, but with no effect on the uptake of Ca or Mg. Nitrogen addition increased aboveground net primary productivity(ANPP) but declined plant species diversity and community stability. Phosphorus addition alone increased total P and Olsen-P contents and fungal abundance in the surface soil, and improved N, P and S uptake by leaves, but had no significant influence on other soil basic chemical properties, ANPP, and plant species diversity. Water addition could improve the resistance of plant community, but its contribution to ANPP was limited by soil N availa-bility. Water addition could buffer soil acidification and the decline of microbial and plant diversity induced by N addition. Under the treatments of N and water addition or P and water addition, the diversity and function of soil microorganisms were affected by plant community structure and function. Long-term controlled field experiments were useful for understanding ecosystem structure and functions of grasslands. However, to uncover the underlying mechanisms in grassland ecosystem ecology, single-site experiments should be incorporated with multiple-site controlled field experiments in different regions. More attentions should be paid to the linkage of above-and below-ground ecological processes.

关 键 词：土壤酸化 氮沉降 养分有效性 微生物生态 生物多样性 

分 类 号：S812.2[农业科学—草业科学]