摘要
采用经典统计学和地统计学相结合的方法,研究广西10类主要森林类型不同土层(0~10、10~20、20~30、30~50、50~100 cm)土壤有机碳含量的空间异质性。结果表明:广西森林不同土层土壤有机碳平均含量变化为8.01~29.78 g·kg-1,变异系数在50.27%~74.89%之间;10~20 cm土层土壤有机碳的半变异函数符合球状模型,其余土层符合指数模型,且拟合效果均较好;各土层土壤有机碳半变异函数的块金效应为16.75%~49.33%,表现为强烈或中等强度的空间自相关性;Kriging插值结果显示,不同森林各土层土壤有机碳含量的分布具有一定相似的空间分布特征,总体表现为北高南低,最高和最低值分别出现在东北和东南;广西不同森林类型不同土壤深度土壤有机碳含量和变异系数不同,0~100 cm土壤有机碳平均含量的大小顺序为硬阔>杉木>石山林>软阔>竹林>八角>桉树>油茶>栎类>松树,总体上土壤有机碳含量随土壤深度的增加而降低,变异系数则相反。广西森林土壤的空间异质性受结构性和人为因素的共同制约,其中结构性因素起主导作用。因此,加强自然林封育和人工林保育、优化调控桉树林和经济林种植规模是提高广西森林固碳潜力的重要措施。
By combination of classical statistics,geostatistics and geographic information system,the spatial heterogeneity of soil organic carbon( SOC) in different layers( 0-10,10-20,20-30,30-50 and 50-100 cm) of ten kinds of major forest types in Guangxi were studied. Soil samples were collected from 115 sampling locations and 345 plots( 50 m ×20 m),according to 10 km × 10 km grid. The results showed that the average content of SOC in different forests in Guangxi ranged from 8.01 to 29.78 g·kg-1 and the coefficient of variation( CV) ranged from 50.27% to 74.89%. The semivariagram of SOC in 10-20 cm soil layer was best fitted with exponential model whereas those in other soil layers were best fitted with spherical model. The nugget effect of semivariagram of SOC in all soil layers ranged from 16.75% to49.33%,indicating a strong or a moderate spatial autocorrelation. Kriging interpolation results showed characteristics of spatial distribution of SOC in different soil layers were similar,i.e.,higher in the north while lower in the south,and the maximum and minimum occurred in the northeast and the southeast of Guangxi,respectively. The average of SOC and its CV varied with forest type and soil layer,and the average of SOC in 0-100 cm layer followed the order: Castanopsis >Cunninghamia lanceolata > Cyclobalanopsis glauca > Liquidambar > Bambusa multiplex > Octagon > Eucalyptus > Camellia oleifera > Quercus > Pinus. On the whole,SOC decreased with increasing soil depth,while the CV exhibited an opposite trend. The spatial heterogeneity of SOC in forest of Guangxi was synthetically influenced by structural and human factors,while the structural factors played a dominant role. It is suggested that expanding the area of natural forests and plantations like Cunninghamia lanceolata while reducing the area of Eucalyptus and certain economic forests like Camellia oleifera will help increase carbon sequestration potential in forest of Guangxi.
引文
CHEN X,2014.Estimation of soil organic carbon reserves in Guangxi and comparion study with some provinces in China[J].Sci Geogr Sin,34(10):1247-1253.[陈曦,2014.广西土壤有机碳储量估算及与全国部分省区的比较研究[J].地理科学,34(10):1247-1253.]
DING ZL,FU BJ,HAN XG,et al,2009.Brief introduction to a cluster of projects of“research in key issues of international negotiation with regard to coping with climate change”by CAS[J].Bull Chin Acad Sci,24(1):8-17.[丁仲礼,傅伯杰,韩兴国,等,2009.中国科学院“应对气候变化国际谈判的关键科学问题”项目简介[J].中国科学院院刊,24(1):8-17.]
DU H,ZENG FP,SONG TQ,et al,2016.Spatial pattern of soil organic carbon of the main forest soils and its influencing factors in Guangxi,China[J].Chin J Plan Ecol,40(4):282-291.[杜虎,曾馥平,宋同清,等,2016.广西主要森林土壤有机碳空间分布及其影响因素[J].植物生态学报,40(4):282-291.]
GOOVAERTS P,2001.Geostatistical modeling of uncertainty in soil science[J].Geoderma,103(1):3-26.
GUO XM,NIU DK,GUO X,et al,2006.Study on spatial variability of soil nutrients for Moso bamboo forest in Fengxin[J].Plant Nutr Fert Sci,12(3):420-425.[郭晓敏,牛德奎,郭熙,等,2006.奉新毛竹林土壤养分空间变异性研究[J].植物营养与肥料学报,12(3):420-425.]
GUO XD,FU BJ,MA KM,et al,2000.The spatio-temporal variability of soil nutrients in Zunhua plain of Hebei Province:semivariogram and kriging analysis[J].Acta Geogr Sin,11(4):557-563.[郭旭东,傅伯杰,马克明,等,2000.河北省遵化平原土壤养分的时空变异特征-变异函数与Kriging插值分析[J].地理学报,11(4):557-563.]
HUANG Y,SUN WJ,ZHANG W,et al,2010.Changes in soil organic carbon of terrestrial ecosystems in China:A mini-review[J].Sci China Life Sci,53(7):766-775.
JOHN R,DALLING JW,HARMS KE,et al,2007.Soil nutrients influence spatial distributions of tropical tree species[J].Proc Natl Acad Sci,104(3):864-869.
LI BH,ZHANG J,YAO XL,et al,2008.Seasonal dynamic sand spatial distribution patterns of herbs diversity in broad leaved Korean pine(Pinus koraiensis)mixed forest in Changbai Mountains[J].Chin J Appl Ecol,19(3):467-473.[李步杭,张健,姚晓琳,等,2008.长白山阔叶红松林草本植物多样性季节动态及空间分布格局[J].应用生态学报,19(3):467-473.]
LI SY,LIU HY,ZHANG XD,et al,2006.Spatial variability of soil fertility quality indices in northeast China[J].Chin JSoil Sci,37(2):220-225.[李双异,刘慧屿,张旭东,等,2006.东北黑土地区主要土壤肥力质量指标的空间变异性[J].土壤通报,37(2):220-225.]
LIU FC,SHI XZ,YU DS,et al,2004.Characteristics of spatial variability of total soil nitrogen in the typical area of Taihu Lake basin[J].Geogr Res,23(1):163-170.[刘付程,史学正,于东升,等,2004.太湖流域典型地区土壤全氮的空间变异特征[J].地理研究,23(1):163-170.]
LIU L,ZENG FP,SONG TQ,et al,2010.Spatial heterogeneity of soil nutrients in karst area’s Mulun National Nature Reserve[J].Chin J Appl Ecol,21(7):1667-1673.[刘璐,曾馥平,宋同清,等,2010.喀斯特木论自然保护区土壤养分的空间变异特征[J].应用生态学报,21(7):1667-1673.]
LU P,PENG PQ,SONG BL,et al,2005.Geostatistical and GISanalyses on soil total P in the typical area of Dongting Lake Plain[J].Sci Agric Sin,38(6):1204-1212.[路鹏,彭佩钦,宋变兰,等,2005.洞庭湖平原区土壤全磷含量地统计学和GIS分析[J].中国农业科学,38(6):1204-1212.]
LU P,HUANG DY,SONG BL,et al,2005.Spatial variability of soil nutrition in the typical landscape unit of red soil hilly in subtropical region[J].Plant Nutr Fert Sci,11(6):717-723.[路鹏,黄道友,宋变兰,等,2005.亚热带红壤丘陵区典型景观单元土壤养分的空间变异[J].植物营养与肥料学报,11(6):717-723.]
LUO YJ,ZHANG XQ,WANG XK,et al,2009.Forest biomass Estimation method and their prospcets[J].Sci Silv Sin,45(8):129-134.[罗云建,张小全,王效科,等,2009.森林生物量的估算及其研究进展[J].林业科学,45(8):129-134.]
LUYSSAERT S,SCHULZE ED,BORNER A,et al,2008.Old growth forests as global carbon sinks[J].Nature,455(7210):213-215.
MA FY,LI XR,ZHANG JG,et al,2006.Spatial heterogeneity of soilmoisture in Shapotou sand-fixing artificial vegetation area[J].Chin J Appl Ecol,17(5):789-795.[马风云,李新荣,张景光,等,2006.沙坡头人工固沙植被土壤水分空间异质性[J].应用生态学报,17(5):789-795.]
MA JM,LIANG SC,YANG DL,et al,2013.Characteristics of content and density of soil organic carbon in Eucalptus grandis×E.urophylla forest and the other three forest types in northern Guangxi[J].J Ecol Environ,22(8):1282-1287.[马姜明,梁士楚,杨栋林,等,2013.桂北地区桉树林及其他三种森林类型土壤有机碳含量及密度特征[J].生态环境学报,22(8):1282-1287.]
MCGRATH D,ZHANG CS,CARTON OT,2004.Geostatistical analyses and hazard assessment on soil lead in Silver mines area,Ireland[J].Environ Poll,127(2):239-248.
PAN Y,BIRDSEY RA,FANG J,et al,2011.A large and persistent carbon sink in the world’s forests[J].Science,333(6045):988-993.
PENMAN J,GYTARSKY M,HIRAISHI T,et al,2003.Good practice guidance for land use,land-use change and forestry[J].IPCC,35(5):103-105.
SONG TQ,PENG WX,ZENG FP,et al,2009.Spatial heterogeneity of soil moisture in dry season in Mulun National Nature Reserve in karst area[J].Chin J Appl Ecol,20(1):99-104.[宋同清,彭晚霞,曾馥平,等,2009.喀斯特木论自然保护区旱季土壤水分的空间异质性[J].应用生态学报,20(1):99-104.]
XIONG HF,WANG YH,2005.Spatial heterogeneity of soil nutrients in wetland of Liangzi Lake[J].Plant Nutr Fert Sci,11(5):584-589.[熊汉锋,王运华,2005.梁子湖湿地土壤养分的空间异质性[J].植物营养与肥料学报,11(5):584-589.]
WANG DP,WANG WB,ZHENG L,et al,2014.Compared of soil organic carbon of different plantations in China[J].JEcol Environ,23(4):698-704.[王大鹏,王文斌,郑亮,等,2014.中国主要人工林土壤有机碳的比较[J].生态环境学报,(4):698-704.]
WANG ZQ,1999.Statistics and its application in ecology[M].Beijing:Science Press:71-99.王政权,1999.地统计学及在生态学中的应用[M].北京:科学出版社:71-99.]
WOODWELL GM,WHITTAKER RH,REINERS WA,et al,1978.The biota and the world carbon budget[J].Science,199(4325):141-146.
WU JG,2002.Landscape ecology:pattern,process,scale and hierarchy[M].Beijing:Higher Education Press.[邬建国,2002.景观生态学:模式、流程、规模和层次结构[M].北京:高等教育出版社.]
WU ZF,ZHAO YF,QI L,et al,2012.Effect of scale of model on prediction of soil organic matter in complex landscape region[J].Acta Pedol Sin,50(2):296-305.[巫振富,赵彦锋,齐力,等,2013.复杂景观区土壤有机质预测模型的尺度效应[J].土壤学报,50(2):296-305.]
ZHANG JG,CHEN HS,SU YR,et al,2008.Spatial and temporal variability of surface soil moisture in the depression area of karst hilly region[J].Acta Pedol Sin,45(3):544-549.[张继光,陈洪松,苏以荣,等,2008.喀斯特山区洼地表层土壤水分的时空变异[J].土壤学报,45(3):544-549.]
ZHANG QZ,WANG CK,2010.Carbon density and distribution of six Chinese temperate forests[J].Sci China Life Sci,53(7):831-840.
ZHANG ZX,XU MX,WU YB,et al,2013.Spatial variability of soil organic carbon of croplands in the hilly Loess Plantau region of China:a case study in Zhuanglang County,Gansu Province[J].Plant Nutr Fert Sci,19(4):955-963.[张志霞,许明祥,吴永斌,等,2013.黄土丘陵区县域农田土壤有机碳空间变异性-以甘肃庄浪县为例[J].植物营养与肥料学报,19(4):955-963.]
ZHOU GY,LIU S,LI Z,et al,2007.Old-growth forests can accumulate carbon in soils[J].Science,314(5804):1417.