贵阳喀斯特地区植被类型与季节变化对土壤微生物生物量和微生物呼吸的影响  

Influence of vegetation types and seasonal variation on soil microbial biomass and microbial respiration in Karst region of Guiyang,southwest China

作　　者：彭艳[1,2] 李心清[1] 程建中[1,2] 邢英[1,2] 闫慧[1,2] 

机构地区：[1]中国科学院地球化学研究所环境地球化学国家重点实验室,贵州贵阳550002 [2]中国科学院研究生院,北京100049

出　　处：《地球化学》2010年第3期266-273,共8页Geochimica

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-YW-306-3);国家重点基础研究发展计划项目(2006CB403205);中国科学院创新团队国际合作伙伴计划项目

摘　　要：土壤微生物特性是土壤修复的指示因子,近年来西南喀斯特地区退化土壤的相关研究较多,但不同植被类型的土壤微生物特性的变化研究相对较少。对贵阳郊区耕作土壤、灌丛、女贞人工纯林和马尾松人工纯林表层土壤(0～10cm)微生物生物量碳(SMBC)、微生物呼吸(MR)和微生物代谢熵(qCO2)的研究结果表明,土壤SMBC和MR均表现为次生林高于耕作土壤,灌丛最高;与qCO2相反,马尾松林土壤微生物活动显著弱于其他样地,不同植被类型土壤微生物活动均表现为在秋季相对较强。与植被类型的显著影响相比,季节变化、植被与季节的交互作用对SM-BC和MR的影响不明显。SMBC与土壤温度不相关,与土壤含水量呈极显著相关而土壤含水量季节变化不明显,MR与土壤温度和含水量均无显著相关性可能是季节变化对两者影响不明显的主要原因,但需要大量区域样本进一步证实。认为演替初期的灌丛比人工阔叶或针叶纯林更有利于土壤微生物群落的生长,土壤有机质积累较快,植被自然恢复是喀斯特退化土壤恢复初期更适合的途径。Soil microbial properties are direct indicators to soil remediation. Great efforts have been made to combat the soil degradation in the Karst regions in southwest China recent years, fewer researches, however, have been performed to examine changes of microbial characteristics of soils in different vegetation types. We measured soil microbial biomass C （SMBC）, microbial respiration （MR） and microbial metabolic quotient （qCO2） on surface soil （0 - 10 cm） in tilled field, shrub, Ligustrum lucidum forest and Pinus massoniana forest in Guiyang, Guizhou Province. The data revealed that SMBC and MR were higher in secondacy forests than in tilled field and the shrub plot had the highest values. Contrary to the qCO2, soil microbes activities were significantly weaker in the Pinus massoniana forest than other sampling plots and autumn had strong soil microbes activities among all vegetation types. Compared to the significant effect of vegetation types, seasonal variation and the interaction of vegetation and season had no impact on the SMBC and the MR. The SMBC was not correlated with soil temperature but significantly related to soil water content which had no obvious seasonal variation. Furthemlore, MR was not significantly related to either soil temperature or water content, which might be main reasons for no significant seasonal effect. A large number of regional samples are needed to further confirm this speculation. The resuhs suggested that shrub plant is preferable to the pure broad-leaf or needle plant for soil microbial communities and has more rapid accumulation rate of soil organic matter. Natural plant community development is the most appropriate way to the remediation of degraded Karst soils in the early stage of the soil remediation.

关 键 词：植被类型 季节变化 土壤微生物生物量 微生物呼吸 自发演替 

分 类 号：P595[天文地球—地球化学] S154.2[天文地球—地质学]