垦殖对桂林会仙喀斯特湿地土壤养分与微生物活性的影响  

Effects of Reclamation on Soil Nutrients and Microbial Activities in the Huixian Karst Wetland in Guilin

作　　者：黄科朝 沈育伊[2] 徐广平[1] 黄玉清[1] 张德楠[1] 孙英杰[1] 李艳琼[1] 何文[1] 周龙武 HUANG Ke-chao1, SHEN Yu-yi2, XU Guang-ping1 , HUANG Yu-qing1, ZHANG De-nan1, SUN Ying-jie1, LI Yan-qiong1 , HE Wen1, ZHOU Long-wu1(1. Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin 541006, China; 2. Guangxi Key Laboratory of Functional Phytochemieals Research and Utilization, Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Seiences, Guilin 541006, Chin)

机构地区：[1]广西壮族自治区中国科学院广西植物研究所广西喀斯特植物保育与恢复生态学重点实验室,桂林541006 [2]广西壮族自治区中国科学院广西植物研究所广西植物功能物质研究与利用重点实验室,桂林541006

出　　处：《环境科学》2018年第4期1813-1823,共11页Environmental Science

基　　金：国家自然科学基金项目(41361057;31760162;31360202);广西林业科技项目(桂林科字[2013]第14号);广西科技攻关计划项目(桂科攻14124004-3-5:桂科重1598014-3);国家科技支撑计划项目(2012BAC16B01);广西喀斯特植物保育与恢复生态学重点实验室基金项目(16-380-32)

摘　　要：选择桂林会仙喀斯特湿地不同垦殖方式的土壤为研究对象,通过研究原生沼泽湿地及其开垦21 a的水田和旱地0~40cm不同深度的土壤理化性质、微生物数量、酶活性、微生物呼吸等变化趋势,以揭示垦殖对会仙喀斯特湿地土壤质量的影响.结果表明:(1)垦殖导致会仙喀斯特湿地土壤呈现偏酸性和养分含量降低的趋势,垦殖后土壤有机碳(SOC)、全氮(TN)、速效氮(AN)、全磷(TP)、速效磷(AP)、全钾(TK)和速效钾(AK)总体上趋于减小,并且表层土壤减小的趋势最为显著.(2)垦殖改变了土壤微生物数量分布的相对比例关系,水田土壤的细菌和放线菌数量最高,而土壤真菌数量则在旱地最高(P<0.001).(3)垦殖降低了各土层蛋白酶、蔗糖酶、脲酶、过氧化氢酶和多酚氧化酶的活性,在旱地的数值最低.(4)垦殖后土壤微生物量碳(MBC)、微生物量氮(MBN)、基础呼吸(BR)、呼吸势(PR)和微生物熵(q MB)总体上均趋于减小,代谢熵(qCO_2)在湿地表现为先增大后减小的趋势,而在水田和旱地则一致表现为逐渐升高的趋势.各土层的MBC、MBN、BR、PR和q MB普遍呈现出湿地>水田>旱地的趋势.qCO_2在0~10 cm和10~20 cm土层表现为湿地>水田>旱地,而在20~30cm和30~40 cm土层则表现为旱地>水田>湿地.综上,垦殖显著降低了土壤的微生物活性,土壤质量呈现下降趋势,对旱地土壤影响较为严重.在会仙喀斯特湿地生态恢复过程中,应减少垦殖旱地和水田的面积,退耕恢复湿地面积.To investigate the effect of reclamation on soil quality in the Huixian Karst Wetland, samples from different soil levels were collected from marsh wetland, reclaimed paddy field, and reclaimed dry farmland, for analyzing soil nutrient （ carbon, nitrogen, phosphorous, and potassium） contents, microbial biomass carbon/nitrogen （MBC/MBN）, and microbial activity indicators [ i. e. basal respiration （BR） , potential respiration （PR） , microbial quotient （qMB） , and metabolic quotient （ qCO2 ） ]. The correlations between the soil nutrient contents and soil microbial activity indictors were examined. The results showed that： ①Artificial reclamation led to the trend of slight acidity in the soil and a marked loss in soil nutrients, while, the pH value, soil water content （SWC） , and the contents of soil organic carbon （SOC）, total nitrogen （TN）, available nitrogen （AN）, total phosphorus （TP）, available phosphorus （AP）, total potassium （TK）, and available potassium （AK） decreased with reclamation. ②Among all the microbes, bacteria were the most numerous, followed by actinomycetes, and fungi were the least numerous. The microbial quantity decreased with the increase in the soil depth on the whole. The proportion of bacteria and actinomycetes were much higher in the paddy field, and that of fungi was the highest in the dry farmland. ③ In total, protease, sucrase, urease, catalase, and polypheno] oxidase activities decreased with the increasing of soil depths. Soil reclamation reduced the soil enzyme activities. ④qCO2 decreased after an initial increase in the marsh wetland, while it rose gradually in the reclaimed paddy field and reclaimed dry farmland. The contents of MBC, MBN, BR, PR, and qMB were the highest in the marsh wetland, followed by those in the reclaimed paddy field, with the lowest contents occurring in the reclaimed dry farmland. The trend of qCO2 contents in the 0-10 cm and 10-20 cm soil layers followed the order of marsh wetland 〉 paddy fi

关 键 词：垦殖 喀斯特湿地 微生物活性 土壤理化性质 土层深度 

分 类 号：X172[环境科学与工程—环境科学]