黄土区不同土地利用类型下砂质壤土地表CO_(2)通量变化特征——以清凉寺沟流域为例  

Study on the change of surface CO_(2) flux in sandy loamy soil under different land use types:An example from the Qingliangsi ditch watershed

作　　者：许志平 邵天杰 张连凯[2] 邵明玉 牛俊杰 XU Zhiping;SHAO Tianjie;ZHANG Liankai;SHAO Mingyu;NIU Junjie(School of Geographical Science and Tourism,Shaanxi Normal University,Xi’an 710119,Shaanxi,China;Institute of Karst Geology,Chinese Academy of Geological Sciences,Guilin 541004,Guangxi,China;Research Center for Scientific Development of Fenhe River Valley,Taiyuan Normal University,Taiyuan 030012,Shanxi,China)

机构地区：[1]陕西师范大学地理科学与旅游学院,陕西西安710119 [2]中国地质科学院岩溶地质研究所,广西桂林541004 [3]太原师范学院汾河流域科学发展研究中心,山西太原030012

出　　处：《干旱区研究》2021年第4期1000-1009,共10页Arid Zone Research

基　　金：国家自然科学基金面上基金项目(41671213);陕西省博士后科学基金项目(2016BSHEDZZ27)。

摘　　要：利用LI-8100A土壤碳通量自动测量系统对晋西北黄土丘陵沟壑区清凉寺沟流域地表土壤CO_(2)通量进行测量,探讨了CO_(2)通量时空变化特征、不同土地利用类型下的CO_(2)通量特征以及环境因子对CO_(2)通量的影响,对于晋西北黄土丘陵沟壑区小流域地区地表土壤CO_(2)通量的研究进行补充。结果表明:(1)CO_(2)通量在生长季呈现单峰变化,于日出前后达单日最低值,在16:00—22:00达到单日最高值;在非生长季则呈现不规律变化。(2)农耕地的CO_(2)通量相较于荒草地以及枣林地的CO_(2)通量要低;不同季节的CO_(2)通量关系为8月CO_(2)通量最大,5月CO_(2)通量次之,11月CO_(2)通量最低。(3)地表土壤CO_(2)通量与光合有效辐射、大气温度、土壤温度、土壤含水率、土壤有机质、土壤质地等因素密切相关,通过科学的土地利用方式可有效提高土壤的固碳能力。Global climate change is closely related to the carbon cycle,and exploring changes in surface carbon emissions is an essential aspect of climate change research.In this study,the CO_(2)fluxes of surface soils in Qingliangsigou watershed of Loess Hills and Gullies in northwest Shanxi were measured using an LI-8100A soil carbon flux automatic measurement system,the soil particle size was measured using a laser particle size analyzer(mastersizer 2000),the soil organic matter was measured using a chemical titration method,and the soil water content was measured using the drying method.Additionally,we explored the diurnal and spatial variation of surface soil CO_(2)fluxes,temporal and spatial changes,CO_(2)fluxes under different land use types,and the influence of environmental factors on surface soil CO_(2)fluxes to complement the study of surface soil CO_(2)fluxes in small watershed areas in the Loess Hills and Gullies of northwest Shanxi.We found that CO_(2)fluxes showed a single peak in variation during the growing season,reaching a single day minimum around sunrise and a single day maximum between 16:00 and 22:00,and in the non-growing season,there was irregular variation.The CO_(2)fluxes of farmland were lower than the CO_(2)fluxes of waste grassland and jujube forest land.The highest CO_(2)fluxes were observed in August,followed by May,and the lowest CO_(2)flux was in November.The CO_(2)flux of surface soil was closely related to photosynthetic effective radiation,atmospheric temperature,soil temperature,soil water content,soil organic matter,and soil texture.Therefore,the carbon fixation of soil can be effectively improved through scientific land use.In conclusion,the results of this study can be applied to most of the Loess Plateau and used to improve the ecological environment.

关 键 词：土壤CO_(2)通量 时空变化特征 影响因素 土地利用类型 黄土丘陵沟壑区 晋西北 

分 类 号：S154.1[农业科学—土壤学]