文献类型：期刊文献

中文题名：华北刺槐林与自然恢复植被土壤微生物量碳、氮含量四季动态

英文题名：Seasonal Dynamics of Microbial Biomass Carbon and Nitrogen in Soil of Robinia pseudoacacia Forests and Near-Naturally Restored Vegetation in Northern China

作者：王风芹[1] 田丽青[1] 宋安东[1] 桑玉强[2] 张劲松[3] 高峻[3]

第一作者：王风芹

机构：[1]河南农业大学生命科学学院农业部农业微生物酶工程重点实验室;[2]河南农业大学林学院;[3]中国林业科学研究院林业研究所国家林业局林木培育重点实验室

年份：2015

卷号：51

期号：3

起止页码：16-24

中文期刊名：林业科学

外文期刊名：Scientia Silvae Sinicae

收录：CSTPCD;;Scopus;北大核心:【北大核心2014】；CSCD:【CSCD2015_2016】；

基金：林业公益性行业科研专项项目(201404206-03;201104008)

语种：中文

中文关键词：华北土石山区;退耕还林;刺槐;自然恢复植被;微生物量碳/氮

外文关键词：rocky mountain of northern China; converting farmland to forest; Robinia pseudoacacia; naturally restored vegetation; microbial biomass carbon and nitrogen

分类号：S718.5

摘要：【目的】土壤微生物量碳、氮是植被所需碳、氮的重要＂源＂或＂库＂,是公认的综合评价土壤质量或肥力的重要指标,也是土壤生态系统变化的预警及敏感指标,研究其动态变化,可为退耕还林及后期管理决策提供科学依据,并为深入研究林地碳氮循环及温室气体排放提供参考。【方法】以农田（FL）为对照,研究华北土石山区10年生刺槐林、43年生刺槐林、自然恢复植被（NRV）土壤微生物量碳、氮的四季动态变化,并对各样地微生物量碳、氮对土壤营养库的贡献率进行对比研究。【结果】各样地微生物量碳、氮随土层加深而逐渐下降,其季节动态变化差异显著;农田、自然恢复植被、10和43年生刺槐林地0-20 cm土层微生物量碳、氮含量四季均值分别为251.94,290.68,150.66,197.34 mg·kg^-1和30.95,46.46,36.55,45.27 mg·kg^-1。其中：自然恢复植被的微生物量碳、氮含量四季均值最高,其微生物量碳含量分别是农田、10和43年生刺槐林的1.15,1.93和1.47倍,微生物量氮含量分别是它们的1.50,1.27和1.03倍;土壤微生物量碳、氮含量随刺槐树龄增大而升高,43年生刺槐林0-20 cm土层的微生物量碳、氮含量是10年生刺槐林的1.31和1.24倍。各植被样地不同层次土壤微生物量碳氮比季节差异明显,农田、自然恢复植被、10年和43年生刺槐林0-20 cm土层碳氮比四季均值分别为8.64,6.26,4.12和4.36;10,43年生刺槐林碳氮比分别是农田的0.48和0.50倍,是自然恢复植被的0.66和0.70倍。在0-20 cm土层中,农田、自然恢复植被、10和43年生刺槐林地微生物量碳对土壤有机碳平均贡献率分别为1.88%,2.00%,1.54%和1.24%,土壤微生物量氮对土壤全氮的平均贡献率分别为1.21%,5.44%,3.55%和2.26%。【结论】各样地土壤微生物量碳、氮之间显著相关,它们与土壤全氮、有机质和速效钾含量均显著相关;除此之外,土壤微生物量碳还与土壤硝态氮含量显著相关。随着树龄的增加刺槐林土壤微生物量尤其是微生物量氮含量显著提高,因而土壤的生物肥力也显著提高;由土壤微生物量碳、氮含量及其对土壤营养库的贡献率可知,自然恢复植被更利于土壤微生物结构、功能的恢复和生物活性的改善。
【Objective】Microbial biomass carbon and nitrogen are an important ＂source＂or ＂storeroom＂for vegetation＇s requirements. They are important index of comprehensive evaluation of soil quality or fertility,and also sensitive earlywarning indicators of soil ecosystem. This study aims at providing a scientific basis for converting farmland to forests and making decisions of forest management,and providing basis for further study on the C and N cycle and greenhouse gas emission at forestland. 【Method】Seasonal dynamics of soil microbial biomass C and N and their contribution rates to soilnutrition pools in the Robinia pseudoacacia plantation land with tree ages of 10-year-old（ RP10） and 43-year-old and naturally restored vegetation（ NRV） were studied and compared to those of the farmland（ FL） in the rocky mountain region of northern China. 【Results】Microbial biomass C and N of all lands were sharply decreased with increasing soil depth. Seasonal dynamics of microbial biomass C and N contents were different significantly among all these lands. Soil microbial biomass C and N contents in 0- 20 cm soil layer of FL,NRV,RP10 and RP43 were 251. 94,290. 68,150. 66,197. 34 mg·kg^-1and 30. 95,46. 46,36. 55,45. 27 mg·kg^-1,respectively. Soil microbial biomass C and N contents of NRV were much higher than that of other lands,1. 15,1. 93,1. 47 times,and 1. 50,1. 27,1. 03 times of that in FL,RP10 and RP43,respectively. Microbial biomass C and N contents in 0- 20 cm soil layer in RP43 were significantly higher than that of RP10（ 1. 31 and 1. 24 times,respectively）,indicating an increase with forest age.Seasonal dynamics of microbial biomass C- N ratio were different significantly among all lands,and the seasonal means of FL,NRV,RP10 and RP43 were 8. 64,6. 26,4. 12 and 4. 36,respectively. Soil microbial biomass C-N ratio of RP10 and RP43 were 0. 48 and 0. 50 times of that of FL,0. 66 and 0. 70 times of NRV. The average contribution rates of soil microbial biomass C to soil organic carbon in FL,NRV,RP10 and RP43 were 1. 88%,2. 00%,1. 54% and 1. 24% in0- 20 cm soil layer,respectively,and the contribution rates of soil microbial biomass N to soil total nitrogen were1. 21%,5. 44%,3. 55% and 2. 26%. A significantly positive correlation was found between soil microbial biomass C and N,and they were also significantly positively correlated with soil content of total N,organic matter and available potassium.In addition,soil microbial biomass C was also significantly positively correlated with soil ammonium-N content. Microbial biomass in soil,especially microbial biomass N,could be enhanced with increasing forest age of R. pseudoacacia to significantly elevate the soil biological fertility. Based on the comparison of soil microbial biomass C and N content and its contribution to soil N pools among the different lands,we can conclude that the naturally restored vegetation was more conducive to the recovery of soil microbial structure and function and could improve the biological activity of soil.