起源喀斯特溶洞湿地稻田与旱地土壤的微生物数量、生物量及土壤酶活性比较  

Comparisons of Microbial Numbers, Biomasses and Soil Enzyme Activities Between Paddy Field and Dryland Origins in Karst Cave Wetland

作　　者：靳振江[1,2,3] 曾鸿鹄[1,3] 李强[2] 程亚平[1,3] 汤华峰 李敏[3] 黄炳富 

机构地区：[1]桂林理工大学广西环境污染控制理论与技术重点实验室,桂林541004 [2]中国地质科学院岩溶地质研究所,国土资源部/广西岩溶动力学重点实验室,桂林541004 [3]桂林理工大学环境科学与工程学院,桂林541004

出　　处：《环境科学》2016年第1期335-341,共7页Environmental Science

基　　金：国家自然科学基金项目(41361054,41003038,51268008);广西自然科学基金项目(2011GXNSFD018002,2011GXNSFA018006,2010GXNSFB013004);岩溶动力学重点实验室基金项目(KDL2010-02,KDL2011-10);广西高等学校立项科研项目(201204LX162,201106LX229);广西科学研究与技术开发计划项目(桂科合14123001-13);桂林市科学研究与技术开发计划项目(20140122-1);广西高等学校高水平创新团队及卓越学者计划项目

摘　　要：本研究的目的是比较起源于天然湿地的稻田湿地与旱地土壤微生物特征的差异.以桂林会仙喀斯特溶洞湿地系统内的稻田湿地、天然湿地和旱地表层(0~20 cm)土壤为研究对象,采用平板菌落计数法与氯仿熏蒸提取法和试剂盒提取法分别测定微生物数量与微生物生物量和微生物DNA,采用比色法测定土壤酶活性.结果表明,稻田湿地的细菌数量为(4.36±2.25)×10~7CFU·g^(-1),显著高于天然湿地和旱地;稻田湿地和旱地的真菌数量分别为(6.41±2.16)×10~4 CFU·g^(-1)和(6.52±1.55)×10~4 CFU·g^(-1),显著高于天然湿地,而旱地的放线菌数量为(2.65±0.72)×10~6 CFU·g^(-1),显著高于天然湿地.稻田湿地微生物DNA质量分数为(11.92±3.69)μg·g^(-1),显著高于旱地.稻田湿地的蔗糖酶活性为(66.87±18.61)mg·(g·24 h)^(-1),显著高于旱地,天然湿地的碱性磷酸酶活性为(2.07±0.99)mg·(g·2h)^(-1),显著高于旱地.统计分析显示,碱性磷酸酶活性、微生物生物量碳和微生物DNA质量分数与土壤pH、土壤有机碳、总氮、碱解氮、土壤水分、交换性Ca^(2+)和交换性Mg^(2+)呈显著的正相关关系,蔗糖酶活性与前4种土壤因子也呈显著的正相关关系.以上结果表明,微生物生物量和微生物功能活性对会仙喀斯特溶洞湿地土地利用方式变化的反应比较敏感,土壤含水量、pH、Ca^(2+)和Mg^(2+)等理化因子与土壤有机碳等养分是影响土壤微生物数量和活性的主要因子.鉴于天然湿地和稻田湿地土壤微生物特征的相似性,把适量稻田湿地作为一种特殊的人工湿地在喀斯特湿地系统的缓冲区和实验区中加以保留并加以保护较为合理.The purpose of this study is to compare microbial number,microbial biomass as well as soil enzyme activity between paddy field and dryland originated karst wetland ecosystems.The soil samples（0-20 cm） of uncultivated wetland,paddy field and dryland were collected in Huixian karst cave wetland,Guilin,China.Microbial numbers and biomass were detected using dilute plate incubation counting and chloroform fumigation-extraction,respectively.Microbial DNA was extracted according to the manufacturer＇s instructions of the kit.Microbial activity was examined using soil enzyme assays as well.The result showed that the bacteria number in paddy filed was（4.36 ±2.25）×10^7 CFU·g^-1,which was significantly higher than those in wetland and dryland.Fungi numbers were（6.41 ±2.16） ×10^4 CFU·g^-1 in rice paddy and（6.52 ± 1.55） ×10^4 CFU·g^-1 in wetland,which were higher than that in dryland.Actinomycetes number was（2.65 ± 0.72） ×10^6CFU·g^-1 in dryland,which was higher than that in wetland.Microbial DNA concentration in rice paddy was（11.92 ± 3.69） μg·g^-1,which was higher than that in dryland.Invertase activity was（66.87 ±18.61） mg·（g·24 h）^-1 in rice paddy and alkaline phosphatase activity was（2.07 ±0.99） mg·（g·2 h）^-1 in wetland,both of which were higher than those in dryland.Statistical analysis showed there was a significant positive correlation of microbial DNA content,alkaline phosphatase activity and microbial carbon with soil pH,soil organic carbon（SOC）,total nitrogen,alkali-hydrolyzable nitrogen,soil moisture,exchangeable Ca-（2＋） and exchangeable Mg-（2＋）,as well as a significant positive correlation of intervase activity with the former three microbial factors.The above results indicated that microbial biomass and function responded much more sensitively to land-use change than microbial number in karst cave wetland system.Soil moisture,SOC and some factors induced by land-use change could affect mainly microbiological characteristics.We suggest

关 键 词：土地利用 喀斯特溶洞湿地系统 稻田湿地 旱地 土壤微生物 

分 类 号：X172[环境科学与工程—环境科学]