石漠化地区核桃林生态经济效益分析VIP免费

毕业论文2012年05月20日题目广西凤山县石漠化地区核桃林生态经济效益分析学院（系）：专业：班级：学号：学生姓名：指导教师：摘要本文选取广西凤山县石漠化治理中大力较广种植的“核桃”作为研究对象，对其进行生态效益和经济效益分析。生态效益从林下植被多样性、土壤理化性质、生物量三个方面进行调查研究，经济效益通过调查核桃林历年来的投入成本和产出值记录，分析核桃的收入动态过程及其投入产出比。本文旨在为凤山县退耕还林的效益评价提供一定的参考依据，同时也为桂西北及其他石漠化地区的治理提供一定的借鉴。结果表明：（1）核桃林林下植物物种丰富度和物种多样性均较高，物种分布也比较均匀；（2）8年生核桃林总生物量为4.62t/hm2，乔木层的生物量为3.58t/hm2，灌草层生物量为1.04t/hm2；其乔木的单株生物量平均值为0.255714t/hm2，大于香椿单株生物量平均值为0.227778t/hm2；（3）核桃林土壤含水量大于坡耕地的土壤含水量；土壤总孔隙度分别为52.6%、51.8%，具有良好的通气性；土壤有机质含量、全N含量和速效N、P、K含量均高于坡耕地，说明核桃林的土壤肥力较好。（4）核桃林从第七年开始投产，随着年亩产量的增加每年产值不断增大，第9年可全部收回前期投入成本，全林开始盈利。全林年纯利润随着树龄的增长而增多。盛产期亩产值达到6000元/亩，且盛果期达100多年，经济效益显著。综述所述，核桃在凤山县石漠化治理中兼具良好生态效益和经济效益的树种。关键词：石漠化核桃生态效益经济效益ABSTRACTThepaperselectedtherepresentativestreespecies"JuglansregiaL."astheobjectofstudy,toexploretheirecologicalandeconomicbenefitsanalysis.Ecologicalbenefitsincludedthediversityofunderstoryvegetation,soilproperties,biomass.Economicbenefitsmainlyinvolvedwalnutplantation’sdynamicincomeanditsinput-outputratio.ThisarticleaimedtoprovideareferencebasistoevaluatetheresultofreturningfarmlandtoforestsinFengshan,butalsoforotherpartsofofthenorthwestGuangxiandotherrockydesertificationregion.Theresultsshowedthat:(1)walnutplantation’sspeciesrichnessandspeciesdiversitywerebothhigh,speciesdistributionwasalsoself;(2)8-years-oldwalnutplantation’sbiomasswas4.62t/hm2,arborlayer’sbiomasswas3.58t/hm2,shrubandherblayer’biomasswas1.04t/hm2;itseachwoodbiomasswas0.255714t/hm2,whichwashigherthantoon（0.227778t/hm2）;(3)walnutforest’ssoilmoisturecontentisgreaterthantheslopeofcultivatedland;theirtotalsoilporositywere52.6%and51.8%,whichbothhadgoodventilation;soilorganicmattercontent,totalNcontentandavailableN,P,Kcontentwerehigherthantheslopearableland,theaboveillustratedthatwalnutplantationhadgoodsoilfertility.(4)walnutplantationbegantobearfruitintheseventhyear,withtheincreasingofyield,theoutputvalueincreaseeveryyear.Itisnineyearswhenalltheinitialinvestmentwasrecover.Theflourishingtimewillhave6000yuanpermu,andtheflourishingtimewillcontinue100years,whichallshowedthatwalnutplantationhasasignificanteconomicbenefit.Summary,walnutplantationinFengshanrockydesertificationbothhasgoodecologicalandeconomicbenefit.KEYWORDS:Rockydesertification；JuglansregiaL.；Eco-efficiency；Economicbenefits目录摘要..........................................................................................................................iABSTRACT……………………………………………………………………....ii前言.........................................................................................................................1第一章绪论...........................................................................................................21.1喀斯特石漠化治理及效益评价………………………………………...21.2核桃的特性及其栽植技术…...