高原鼠兔和高原鼢鼠干扰下高寒草甸植物群落多样性与土壤生态化学计量的变化

Changes of plant community diversity and soil ecological stoichiometry in alpine meadow under the disturbance of plateau pika Ochotona curzoniae and plateau zokor Myospalax baileyi

中文关键词:高原鼠兔  高原鼢鼠  植物群落  物种多样性  群落结构  土壤化学计量

keywords:plateau pika  plateau zokor  plant community  species diversity  community structure  soil stoichiometry

中文摘要:为阐明高原鼠兔Ochotona curzoniae和高原鼢鼠Myospalax baileyi干扰下高寒草甸植物群落与土壤特性的变化，在青藏高原高寒草甸区选择不同干扰强度的高原鼠兔单独发生区以及高原鼠兔和高原鼢鼠混合发生区，调查其植物群落结构，测定其土壤化学性质，并运用冗余分析法解析高原鼠兔和高原鼢鼠干扰与植物群落及土壤化学因子的关系。结果表明：混合发生区中的植物群落盖度和均匀度指数均显著低于高原鼠兔单独发生区，其余植物群落和土壤指标在2个调查区间均无显著差异；在高原鼠兔单独发生区，随着干扰强度的增加，植物群落丰富度指数（95%置信限（confidence interval，CI）为0.355~0.853）显著增加，而植物高度（95% CI为1.006~1.566）和土壤有机碳含量（95% CI为7.270~16.270）显著降低；在混合发生区，随着干扰强度的增加，植物群落高度（95% CI为0.088~1.093）、土壤全氮含量（95% CI为-0.140~0.240）和土壤铵态氮含量（95% CI为0.146~1.109）显著升高，而植物群落丰富度指数（95% CI为0.168~0.858）显著降低。表明同区域分布的高原鼠兔和高原鼢鼠干扰对草地植物群落和土壤化学性质的影响高于高原鼠兔单独干扰，建议在鼠害防控中应重点关注鼠类混合发生区的分布及其为害情况，并根据为害等级制订相应的防控措施，以避免草地退化加剧。

Abstract:In order to clarify the changes of plant community and soil characteristics in alpine meadow disturbed by plateau pika Ochotona curzoniae and plateau zokor Myospalax baileyi, the plateau pika and plateau zokor co-existed areas with different interference intensities were selected in the alpine meadow area of the Qinghai-Tibet Plateau. The plant community structure was investigated, the soil chemical properties were determined, and the relationship among plateau pika and plateau zokor interference and plant community and soil chemical factors was analyzed by redundancy analysis. The results showed that the coverage and evenness index of plant communities in the mixed occurrence area were significantly lower than those in the single occurrence area of plateau pika, and there was no significant difference in other plant communities and soil indexes between the two investigation intervals. With the increase of population density in the plateau pika occurrence area, the plant species richness index (95% confidence interval (CI): 0.355-0.853) increased significantly, while the plant height (95% CI: 1.006-1.566) and soil organic carbon content (95% CI: 7.270-16.270) decreased significantly. With the increase of disturbance intensity in the mixed occurrence area, the community plant height (95% CI: 0.088- 1.093), soil total nitrogen content (95% CI: -0.140-0.240) and soil ammonium nitrogen content (95% CI: 0.146-1.109) increased significantly, while the plant community richness (95% CI: 0.168-0.858) decreased significantly. This indicates that the impact of the co-occurrence of plateau pika and plateau zokor on grassland plant communities and soil chemical properties is greater than that of plateau pika alone. It was recommended that attention should be focused on the distribution and damage situation in areas where both species co-exist for controlling small mammal pests. Appropriate control measures should be formulated based on the severity of the damage to prevent further degradation of the grasslands.