植物生态学报 ›› 2008, Vol. 32 ›› Issue (4): 900-907.DOI: 10.3773/j.issn.1005-264x.2008.04.019

• 论文 • 上一篇    下一篇

紫茎泽兰与非洲狗尾草单、混种群落土壤酶活性和土壤养分的比较

蒋智林1, 刘万学1, 万方浩1,*(), 李正跃2   

  1. 1 植物病虫害生物学国家重点实验室, 中国农业科学院植物保护研究所,北京 100094
    2 云南农业大学植物保护学院农业生物多样性与病虫害控制教育部重点实验室,昆明 650201
  • 收稿日期:2007-03-02 接受日期:2008-01-11 出版日期:2008-03-02 发布日期:2008-07-30
  • 通讯作者: 万方浩
  • 作者简介:*E-mail:wanfangh@public3.bta.net.cn
  • 基金资助:
    “973”项目(2002CB111400);国际科技合作项目(2005DFA31090);云南省科技攻关项目(2006SG23);“十一五”国家科技支撑计划课题(2006BAD08A17)

COMPARATIVE STUDIES ON SEASONAL DYNAMICS OF SOIL ENZYMATIC ACTIVITIES AND SOIL NUTRIENT AVAILABILITY IN MONO- AND MIXED- CULTURE PLANT COMMUNITIES OF AGERATINA ADENOPHORAAND SETARIA SPHACLATA

JIANG Zhi-Lin1, LIU Wan-Xue1, WAN Fang-Hao1,*(), LI Zheng-Yue2   

  1. 1State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100094, China
    2Key Laboratory for Agricultural Biodiversity and Pest Management of Ministry of Education, Plant Protection College, Yunnan Agricultural University, Kunming 650201, China
  • Received:2007-03-02 Accepted:2008-01-11 Online:2008-03-02 Published:2008-07-30
  • Contact: WAN Fang-Hao

摘要:

植物对土壤有效养分的影响是植物竞争取胜的重要生态策略之一, 土壤酶活性对土壤有效养分的变化具有重要作用。该文研究了紫茎泽兰(Ageratina adenophora)单种(A)、非洲狗尾草(Setaria sphacelata)单种(S)和两物种混种(A+S)群落4种重要的土壤酶活性和土壤养分的变化及其规律, 并对土壤酶活性与土壤养分进行了相关分析。结果表明: 1)群落S土壤有效氮(NH4+-N和NO3--N)含量高于群落A对应养分含量, 而与群落A+S该养分含量没有显著差异; 群落S土壤有效磷和有效钾含量低于群落A对应指标, 而群落A+S其含量最低。2)群落S、A+S和A土壤蛋白酶和脲酶活性的高低次序分别为S>A+S>A、A+S>S>A; 群落A+S、S和A磷酸酶活性依次升高; 群落A+S、A和S蔗糖酶活性依次降低。3)在生长过程中, 3类群落土壤NO3--N、有效磷和有效钾含量在生长初期(5月)最高, 随后逐渐降低; 土壤NH4+-N含量呈现单峰趋势, 在生长后期(9月)最高。3类群落土壤蛋白酶和蔗糖酶活性随生长时间推移而升高, 在生长末期(11月)最高; 土壤磷酸酶和脲酶酶活性在生长过程中呈现单峰趋势, 在生长旺盛期(7月)最高。3类群落间土壤酶活性与土壤肥力具有较一致的相关性。由此推断, 非洲狗尾草对土壤含氮化合物的活化能力比紫茎泽兰强, 且在种间竞争中能够强烈抑制紫茎泽兰对土壤含磷、含钾化合物的活化能力是其竞争取胜的可能原因; 不同植物群落土壤酶活性的差异是引起土壤有效养分变化的重要驱动机制之一。

关键词: 紫茎泽兰, 非洲狗尾草, 植物竞争, 土壤酶活性, 土壤养分

Abstract:

Aims Our objectives were to determine: 1) the effect of different plant communities on soil enzymatic activities and soil nutrient availability to the plants, 2) the correlation between soil enzymatic activities and soil nutrient availability to the plants, and 3) the potential competition for resources among target species and competitive strategy of each species.

Methods We correlated four soil enzyme activities and availability of three major soil nutrients (N, P and K) in three plant communities: monoculture ofAgeratina adenophora (A), monoculture ofSetaria sphacelata (S), and mixed culture ofA. adenophora and S. sphacelata (A+S).

Important findings Concentrations of soil NH4+-N and NO3--N in community A were significantly lower than in S and A+S (p<0.01), but there was no significant difference between A and A+S (p>0.05). The available P and K in all communities decreased significantly in the order of A>S>A+S (p<0.01). Soil protease and urease activities in all communities decreased in the order of S>A+S>A and A+S>S>A (p<0.01), respectively. Soil phosphatase and invertase activities increased in the order of A+S<S<A and S<A<A+S (p<0.01), respectively. The soil NO3--N and available P and K in all communities decreased with increasing plant age. Soil NH4+-N contents showed a unimodal concentration curve peaking in September. Soil protease and urease activities increased in all communities with peak values in November. The activities of other soil enzymes peaked only once in July. Correlations between soil enzymatic activities and soil nutrient availability were consistent in all communities. S. sphacelata showed higher net ammonification and nitrification rates as compared to A. adenophora, but S. sphacelata showed higher reduction in available P and K. This may explain why S. sphacelata out-competed A. adenophora in community A+S. The differences in soil enzymatic activities of the different plant communities are due to a potential mechanism that resulted in variations in the nutrients availability.

Key words: Ageratina adenophora, Setaria sphacelata, plant competition, soil enzymatic activity, soil nutrients