西南喀斯特典型土壤在不同植被类型下的土壤呼吸特征

Soil respiration characteristic of on typical Karst soils with different vegetation in Karst region of southwest China

为了研究喀斯特地区不同植被类型覆盖下的典型土壤呼吸变化规律,采取野外原位观测的方法,监测了2种典型植被类型(林地和灌草地)下的红壤、棕色石灰土、黑色石灰土在不同时刻的土壤呼吸过程。通过对土壤呼吸的日变化、季节变化和在旱季、雨季的差异的分析,探讨了喀斯特典型土壤的土壤呼吸规律。结果表明,3种土壤不同植被呼吸速率相比,旱季红壤和棕色石灰土的土壤呼吸速率均有:林地>灌草地(P<0.05),黑色石灰土的土壤呼吸速率有:灌草地>林地(P<0.05);雨季为红壤:灌草地>林地(P<0.05),石灰土:林地>灌草地(P<0.05)。灌草地土壤呼吸速率对温度湿度的响应比林地敏感。西南喀斯特地区土壤呼吸特征的变化因植被类型不同而存在差异。不同的植被覆盖状况会影响到土壤呼吸对不同土壤类型的敏感程度。

In order to know soil respiration characteristic of on typical Karst soils with different vegetation in Karst region,a wild observation method was used to test two Karst soils（terra fusca and rendzina） and a contrast soil（red soil） soil respiration rate under shrub-grass or forest land.The soil respiration rate of daily variation,season variation,dry season and rainy season were studied to discuss the characteristics of soil respiration in Karst region of southwest China.The result showed that the soil respiration rate of dry season in three soils were all followed the order of forest land 〉 shrub-grass land（P〈0.05）;the soil respiration rate of rainy season was shrub-grass land 〉 forest land in red soil and forest land 〉 shrub-grass land in Karst soils（P〈0.05）.Soil respiration rate of the shrub-grass land was sensitively to temperature and humidity than of forest land.This implied that soil respiration rate has differences with different vegetation.Therefore,sensitive of soil respiration rate with different soil types were affected by different vegetation.