晋西黄土区退耕还林20年后典型林地的持水能力  

Water-holding capacity of different forestlands 20 years after converted from farmland in loess region,western Shanxi Province

作　　者：王高敏[1] 杨宗儒 查同刚[3] 张志强[3] 吕志远[1] 张晓霞[3] 王红艳[3] 朱嘉磊[1] 

机构地区：[1]北京林业大学林学院 [2]山西省吉县林业服务中心 [3]北京林业大学水土保持学院,水土保持与荒漠化防治教育部重点实验室

出　　处：《北京林业大学学报》2015年第5期88-95,共8页Journal of Beijing Forestry University

基　　金：“十二五”国家科技支撑计划项目(2015BAD07B03)

摘　　要：为探究晋西黄土区退耕20年后典型林地间持水能力的差异,选取山西省吉县蔡家川流域退耕20年的次生林和油松人工林、刺槐人工林、油松×刺槐人工混交林4种典型林分为研究对象,同时以耕地作为对照,通过外业调查和室内测定,比较分析了该地区退耕林分间林地（枯落物层和土壤层）的最大持水量和有效持水量。结果表明：1）次生林枯落物层的最大持水量和有效持水量为201.20和154.32 t/hm2,分别是人工林的1.35～2.14倍和1.33～2.06倍,人工林之间表现为油松×刺槐人工混交林〉刺槐人工林〉油松人工林;2）退耕林地土壤层的最大和有效持水量分别介于5 102～5 563 t/hm2和1 007～1 251 t/hm2之间,均显著高于耕地的4 695和812 t/hm2;典型退耕林地间土壤有效持水量表现为次生林〉油松×刺槐人工混交林〉油松人工林〉刺槐人工林,最大持水量为次生林〉油松×刺槐人工混交林〉刺槐人工林〉油松人工林;3）与退耕引起土壤非毛管孔隙度增加相一致,林地的最大持水量和有效持水量较耕地分别增加了10.7%～22.8%和32.9%～73.1%,表明退耕对林地持水能力的影响在有效持水量方面更突出;4）退耕林分间林地持水能力表现为次生林〉油松×刺槐人工混交林〉刺槐人工林〉油松人工林。林地最大持水量和有效持水量显著高于耕地,这主要源于土壤性质改善引起的土壤层持水能力增强,同时枯落物层的持水功能也发挥了一定作用。总之,退耕20年后林地持水能力显著增强,不同林分间次生林持水能力较好,表明次生林宜作为该地区退耕后植被恢复的主要参考。To compare the water conservation capacity of four typical forest stands converted from farmland 20 years ago in loess region,western Shanxi Province,the maximum water-holding capacity（ WCm） and effective water-holding capacity（ WCe） of litter and soil layers in secondary forest（ SF）,Pinus tabuliformis plantation（ P）,Robinia pseudoacacia plantation（ R） and P. tabuliformis × R. pseudoacacia plantation（ P × R） were examined based on field investigations and laboratory analyses in July 2013,with the farmland as a control（ CK）. The results were as follows： 1） WCmand WCe of litter layer in secondary forest were 201. 20 and 154. 32 t / ha,respectively,which were 1. 35- 2. 14 times and 1. 33-2. 06 times of those in the plantations. Both WCmand WCeshowed the trend as P × R R P. 2）The WCeof the soil layer in four forest stands ranged between 5 102- 5 563 t / ha,and the WCewas 1 007-1 251 t / ha,which were significantly higher than 4 695 and 812 t / ha of the farmland（ CK）,respectively.The WCeshowed the trend as SF P × R P R,while WCmas SF P × R R P. 3） The WCeof the forestlands increased about 32. 9%-73. 1% and much higher than the WCmincrement about10. 7%-22. 8%,which was consistent with the changes of non-capillary porosity. This implied more significant effects of the conversion of farmland to forest（ CFF） on WCethan WCm. 4） The water-holding capacity of the converted forestlands showed the trend as SF P × R R P with significantly higher WCmand WCethan the farmland. This was mainly resulted from the improvement of soil characteristics and then the increase of water-holding capacity in the soil,and also certain water-holding effect of litter layers. In general,the water-holding ability has been significantly improved through the CFF in loess area of western Shanxi Province. The water-holding capacity of the secondary forest was better than the other three plantations,indicating that the secondary forest should be the main type of vegetation restoration in CFF program i

关 键 词：晋西黄土区 退耕还林 林地 最大持水量 有效持水量 

分 类 号：S715.7[农业科学—林学]