养分添加对内蒙古贝加尔针茅草原植物多样性与生产力的影响

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 养分添加对内蒙古贝加尔针茅草原植物多样性与生产力的影响 DOI: 10.5846/stxb201407171461 作者: 作者单位: 沈阳农业大学;农业部环境保护科研监测所,农业部环境保护科研监测所,农业部环境保护科研监测所,沈阳农业大学,农业部环境保护科研监测所,农业部环境保护科研监测所 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(31170435);国家"十二五"科技计划项目(2012BAD13B07);中央级公益性科研院所基本科研业务费专项资金和农业部产地环境质量重点实验室资助项目;天津市农业环境与农产品安全重点实验室开放基金资助项目 Effects of nutrient addition on plant diversity and productivity in a Stipa baicalensis grassland in Inner Mongolia, China Author: Affiliation: Shenyang Agricultural University;Agro-environmental Protection Institute, Ministry of Agriculture,Agro-environmental Protection Institute, Ministry of Agriculture,Agro-environmental Protection Institute, Ministry of Agriculture,Shenyang Agricultural University,Agro-environmental Protection Institute, Ministry of Agriculture,Agro-environmental Protection Institute, Ministry of Agriculture 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:研究养分添加对草地群落植物组分、结构和多样性格局的影响,对退化草地生态系统恢复与重建具有重要的理论和实践意义。以内蒙古贝加尔针茅(Stipa baicalensis)草原为对象,研究了N、P、K养分添加对草地群落植物多样性和生产力的影响。结果表明:1)养分添加显著提升草原初级生产力,其中氮素添加的效果最明显,NPK复合添加,草原初级生产力与对照相比提高了1.31倍。2)养分添加使草地群落结构发生改变,N素添加显著提高了贝加尔针茅和羊草(Leymus chinensis)为主的禾本科植物功能群在草地群落中所占的比重,而豆科植物功能群在草地群落中所占的比重则显著降低。3)养分添加使草原植物多样性不同程度地减少,其中以N素添加的效应较为显著。 4)在养分添加条件下,植物多样性与草原生产力之间呈负线性相关关系,植物多样性、物种丰富度和物种均匀度与初级生产力的相关系数分别为-0.522、-0.391和-0.534。 Abstract:Stipa baicalensis grassland is a type of meadow steppe that plays an important role in livestock husbandry in China. In recent years, unsustainable grazing, mowing, and other overuse patterns have heavily affected China's grassland ecosystems, resulting in decreased productivity and losses in biological diversity and ecosystem stability. The restoration and sustainable use of grassland ecosystems has become a concern in grassland ecology. Low levels of soil nitrogen (N), phosphorus (P), and potassium (K) often become important factors that limit grassland productivity, while arational application of N, P, K and medium trace element fertilizers can obviously promote the productivityand quality of grasslands. Nutrient addition can affect the structure and diversity of grassland plant communities, and studies on the response of grasslands to adding nutrients will have important theoretical and practical significance to the recovery, reconstruction, and scientific management of degraded grassland ecosystems. We studied the effects of added N,P, and K in a S. baicalensis grasslandto provide a basis for the rational use and protection of grassland resources and the restoration and reconstruction of degraded grassland ecosystems, as well as to lay a foundation for a more general analysis of the relationship between biodiversity and productivity.A randomized block design experiment was conducted with six blocks of eight treatments each: C (control, no nutrient addition), K (K addition only, 100 kg/hm2), P (P addition only, 100 kg/hm2), N (N addition only, 100 kg/hm2), PK (mixed P and K addition, 100 kg/hm2of each element), NK (mixed N and K addition, 100 kg/hm2 of each element), NP (mixed N and P addition, 100 kg/hm2 of each element), and NPK (mixed N, P, and K addition, 100 kg/hm2 of each element).Forty-eight (8 m × 8 m)plots were established with 2 m and 5 m isolation belts between the subplots and main treatment areas, respectively. In 2010,nutrients were applied twice a year with 50% of the treatment amount applied on June 15 and 50% again on July 15 during the grass-growing season.Fieldwork was completed in mid-August during the grass-growing season in 2012. To eliminate edge effects,conditions were measured only in the 6 m × 6 m area in the center of each 8 m × 8 m plot.A 1 m2 (1 m × 1 m)quadrat in each 6 m × 6 m plot was used to record various biological and ecological characteristics including plant composition, plant height,percent ground cover, and vegetation density.We evaluated these characteristics to estimate primary productivity and plant diversity. One-way ANOVA was used to calculate the species richness, the Shannon-Wiener and Pielou indices, and to analyze aboveground biomass. The relationships between the diversity indices and aboveground biomass were determined through linear regression. The results showed that all treatments increased primary productivity and reduced plant diversity. N addition, with or without P or K addition,always significantly decreased the Shannon-Wiener and Pielou indices (except for the NP treatment which had no significant effect), but only the NP treatment resulted in a significant decrease in species richness. With the exception of the K treatment,all treatments resulted in significantly increased primary productivity. Among the three nutrients, N was the most effective treatment in increasing plant productivity and diversity; the NPK treatment had the greatest effect, increasing aboveground biomass 1.31 times compared to that of the control. Nutrient addition altered the community structure in that N addition significantly increased the proportion of grasses and reduced that of legumes, but the effects of nutrient addition on the proportion ofcyperaceae and forbs were negligible. With fertilization, plant diversity (correlation coefficient, -0.522), species richness (-0.391), and species evenness (-0.534) were all negatively linearly correlated with primary productivity. In conclusion, the NPK combination treatment resulted in maximum grassland productivity while effectively maintaining plant diversity, resulting in improved environmental conditions and achievingsustainable development. 参考文献 相似文献 引证文献