摘要
对元阳梯田3个海拔梯度[高海拔(1 615～1 682 m)、中海拔(1 532～1 555 m)和低海拔(1 445～1 468 m)]表层土壤(0～30 cm)碳氮组分的含量现状与分布特征进行了研究。结果表明:元阳梯田表层土壤有机碳(TOC)总体达到二级水平,而土壤全氮(TN)、pH值和微生物量碳氮(MBC,MBN)含量较低,土壤溶解性有机碳氮(DOC,DON)含量及其占土壤有机碳、全氮的比值较高,土壤易氧化碳(ROC)和轻组碳氮(LFC,LFN)含量处于中等水平。上述指标均呈现出随海拔的下降而降低的趋势,且元阳梯田土壤DOC,DON,ROC,LFC和LFN与梯田海拔之间呈显著正相关关系(P<0.05)。元阳梯田土壤TOC,TN,MBC,MBN及NH4+-N含量在3个海拔梯度之间均没有显著差异性;而土壤pH值、DON,ROC,LFC和LFN含量均在高海拔梯度显著高于低海拔梯度(P<0.05)。
The carbon and nitrogen contents and distribution characteristics of surface layer soil （0 ～30 cm） at three altitudes [ High altitude （ 1 615 ～ 1 682 m）, Medium altitude （ 1 532 ～ 1 555 m） and Low altitude （ 1 445 ～1 468 m） ] in Yuanyang terraced paddy soils were studied. The resultsshowed that： the surface layer soil organic carbon （TOC） content was up to the ＂second＂ level in average, but the soil total nitrogen （TN） content, pH value and microbial biomass carbon and nitrogen（MBC, MBN） contents were low, the soil dissolved organic carbon and nitrogen （DOC, DON） contents, DOC/TOC ratio and DON/TN ratio were high, and the soil readily oxidizable organic carbon（ROC） content, light fraction carbon and nitrogen （LFC, LFN） contents were medium level. In general, all of the indexes mentioned above decreased along with the fall of altitude, and the altitudeshowed significant positive relation （P 〈 0.05 ） to the soil DOC, DON, ROC, LFC and LFN. There were no significant difference in soil TOC, TN, MBC, MBN and NH4^＋ -N contents among the three al-titudes, and the soil pH value, DON, ROC, LFC and LFN contents at high altitude were significantly higher than that at low altitude （P 〈 0.05 ）.
出处
《云南农业大学学报（自然科学版）》
CAS
CSCD
北大核心
2012年第5期763-769,共7页
Journal of Yunnan Agricultural University:Natural Science
基金
土壤与农业可持续发展国家重点实验室开放基金(0812000051)
国家自然科学基金(31101605)
云南省自然科学基金(2010ZC083)
关键词
溶解性有机碳、氮
微生物量碳、氮
易氧化碳
轻组碳
氮
海拔梯度
dissolved organic carbon and nitrogen
microbial biomass carbon and nitrogen
readilyoxidizable organic carbon
light fraction carbon and nitrogen
altitudinal gradient
