朱晓婷　王克勤　陈敏全　赵吉霞　华锦欣

(西南林业大学，昆明，650224)



昆明松华坝水源区不同土地利用方式对土壤有机碳及活性有机碳组分的影响1)

朱晓婷王克勤陈敏全赵吉霞华锦欣

(西南林业大学，昆明，650224)

以松华坝水源区3种主要的土地利用方式为研究对象，分析了不同土地利用方式0～20 cm的土壤有机碳和碳储量、活性有机碳组分(水溶性有机碳、易氧化有机碳、颗粒有机碳)质量分数及其月动态变化。研究结果表明：(1)不同土地利用方式下土壤有机碳差异显著(p<0.05)，灌木林地的有机碳质量分数为(17.21±0.04)～(22.00±0.15)g·kg-1，坡耕地的有机碳质量分数为(12.26±0.03)～(14.84±0.36)g·kg-1，荒地的有机碳质量分数为(6.13±0.04)～(7.54±0.25)g·kg-1。灌木林地的土壤有机碳明显高于其他样地，荒地的质量分数最低，土壤碳储量、水溶性有机碳、易氧化有机碳、颗粒有机碳的质量分数变化也呈现同样的规律。(2)灌木林地和坡耕地各项指标质量分数的月动态变化显著(p<0.05)，而荒地的则表现的较为平缓(p>0.05)。(3)土壤有机碳质量分数与活性有机碳组分之间及活性有机碳组分两两之间的相关性均达到极显著水平(p<0.01)。

土壤有机碳；土壤活性有机碳组分；土地利用方式；松华坝水源区

Three different land use types in Songhuaba was selected as the study object, we studied the contents of aggregates and total soil organic carbon and carbon storage, as well as soil active organic carbon fractions including dissolved organic carbon, readily oxidized organic carbon and particulate organic carbon in the 0-20 cm soil layer, and analyzed the monthly dynamic changes of soil organic carbon and soil active organic carbon fractions contents of every land use types. Soil organic carbon contents of different land use types showed significant differences (p<0.05), that of shrubland was ranged in (17.21±0.04)-(22.00±0.15)g·kg-1, that of slope cropland was ranged in (12.26±0.03)-(14.84±0.36)g·kg-1, and that of wasteland was ranged in (6.13±0.04)-(7.54±0.25)g·kg-1. Soil organic carbon in shrubland was much higher than that in the other sample plots, while that in wasteland was the lowest, the changes of carbon storage dissolved organic carbon, readily oxidized organic carbon and particulate organic carbon mass fractions also showed the same rule. The monthly dynamic changes of soil organic carbon and soil active organic carbon fractions contents of shrubland and slope cropland showed significant differences (p<0.05), while that of wasteland was comparatively gentle (p>0.05). The relativity of soil organic carbon and soil active organic carbon fractions showed a very significant level(p<0.01). There were significant correlation between any two groups of the soil active organic carbon fractions(p<0.01).

近百年来，全球温度逐渐升高，大气二氧化碳浓度随之升高且仍在持续上升，由此引起的恶劣天气等对人类赖以生存的环境造成极大的威胁。全球气候变暖的现象与二氧化碳、甲烷和氧化亚氮等温室气体的浓度升高有密切关系的理论已经被许多学者证实[1]。土壤有机碳可以评价土壤质量，利于土地可持续利用管理的重要指标。不合理的土地利用，会使土壤有机碳流失，在一定程度上加速了碳循环，陆地生态系统中有机碳储量减少，而大气中的CO2浓度随之增加，全球变暖的趋势急速加剧，从而导致生态系统不平衡，土壤肥力和作物产量受到直接影响。土地利用和土地覆被的变化作为影响土壤有机碳库的重要方式之一，越来越受到学术界的关注。……