桑科草原不同草地利用方式土壤呼吸的动态研究

为探寻更加合理的草地利用方式,以甘肃省夏河县桑科乡高寒草原为研究区,分别设置放牧草地,放牧+施肥草地,放牧+划破补播草地、封育草地、人工草地处理,测定不同草地利用方式土壤呼吸的动态变化。结果表明:(1)土壤呼吸速率大小顺序为放牧+施肥人工封育放牧+划破补播放牧,最大值10.41μmol/(m2·s),最小值4.69μmol/(m2·s),日变化和季节变化均呈单峰曲线,日变化峰值出现在13∶00~14∶00,7月各处理土壤呼吸速率达最大。(2)土壤呼吸温度敏感性Q10值为放牧+施肥放牧人工放牧+划破补播封育,最大值1.826,最小值1.157。(3)土壤呼吸与土壤湿度的非线性相关关系P值大小为放牧+划破补播放牧人工封育放牧+施肥。放牧+施肥处理为最优草地利用方式。

Study on soil respiration rate of alpine meadow under different utilization patterns in Sangkok of Gansu

In order to explore better grassland utilization and management,the soil respiration of alpine meadow under different utilization patterns (grazing,grazing+fertilizing,grazing+reseeding,sward ripping,ze-ro grazing,sown pasture)was studied in Sangkok of Gansu Province.The results showed that the rank of soil respiration rate was grazing+fertilizing > sown pasture >zero grazing >grazing+sward ripping > grazing. The maximum of soil respiration rate was 10.41 μmol/(m2 ·s)and the minimum was 4.69 μmol/(m2 ·s).The curve of daily and seasonal changes of soil respiration were unimodal type,and the daily and month peaks were 13∶00 to 14∶00 and July respectively.The rank of Q10 was grazing+fertilizing > grazing > sown pasture >grazing+sward ripping >zero grazing,the maximum and minimum of Q10 was 1.826 and 1.157 respectively. The rank of non-linear correlations value between soil respiration rate and soil humidity was grazing+sward ripping