昆明松華壩水源區不同土地利用方式對土壤有機碳及活性有機碳組分的影響1)

朱曉婷　王克勤　陳敏全　趙吉霞　華錦欣

(西南林業大學，昆明，650224)

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昆明松華壩水源區不同土地利用方式對土壤有機碳及活性有機碳組分的影響1)

朱曉婷王克勤陳敏全趙吉霞華錦欣

(西南林業大學，昆明，650224)

以松華壩水源區3種主要的土地利用方式為研究對象，分析了不同土地利用方式0～20 cm的土壤有機碳和碳儲量、活性有機碳組分(水溶性有機碳、易氧化有機碳、顆粒有機碳)質量分數及其月動態變化。研究結果表明：(1)不同土地利用方式下土壤有機碳差異顯著(p<0.05)，灌木林地的有機碳質量分數為(17.21±0.04)～(22.00±0.15)g·kg-1，坡耕地的有機碳質量分數為(12.26±0.03)～(14.84±0.36)g·kg-1，荒地的有機碳質量分數為(6.13±0.04)～(7.54±0.25)g·kg-1。灌木林地的土壤有機碳明顯高于其他樣地，荒地的質量分數最低，土壤碳儲量、水溶性有機碳、易氧化有機碳、顆粒有機碳的質量分數變化也呈現同樣的規律。(2)灌木林地和坡耕地各項指標質量分數的月動態變化顯著(p<0.05)，而荒地的則表現的較為平緩(p>0.05)。(3)土壤有機碳質量分數與活性有機碳組分之間及活性有機碳組分兩兩之間的相關性均達到極顯著水平(p<0.01)。

土壤有機碳；土壤活性有機碳組分；土地利用方式；松華壩水源區

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).

近百年來，全球溫度逐漸升高，大氣二氧化碳濃度隨之升高且仍在持續上升，由此引起的惡劣天氣等對人類賴以生存的環境造成極大的威脅。全球氣候變暖的現象與二氧化碳、甲烷和氧化亞氮等溫室氣體的濃度升高有密切關系的理論已經被許多學者證實[1]。土壤有機碳可以評價土壤質量，利于土地可持續利用管理的重要指標。不合理的土地利用，會使土壤有機碳流失，在一定程度上加速了碳循環，陸地生態系統中有機碳儲量減少，而大氣中的CO2濃度隨之增加，全球變暖的趨勢急速加劇，從而導致生態系統不平衡，土壤肥力和作物產量受到直接影響。土地利用和土地覆被的變化作為影響土壤有機碳庫的重要方式之一，越來越受到學術界的關注。……