【作者】 王斐；

【导师】 王鹏程； 雷静品；

【作者基本信息】 华中农业大学 ， 生态学， 2008， 硕士

【摘要】 本研究在总结前人研究的基础之上,以库区退耕还林重点示范区域——兰陵溪小流域为研究区域,选择7种植被恢复模式的径流小区（针阔混交林、马尾松林、栎林、板栗林、柑橘林、茶林、竹林）,并以工程区坡耕地径流小区作为对照,对兰陵溪小流域不同植被恢复模式生态功能效益进行了详细的研究,主要研究成果如下:1.草本植物是各模式土壤种子库物种组成和个体组成的主要部分,种子库密度大小顺序是:坡耕地（12042.67粒/m²）＞柑橘林（10160粒/m²）＞针阔混交林（5605.33粒/m²）＞竹林（3653.33粒/m²）＞板栗林（3642.67粒/m²）＞茶林（3626.67粒/m²）＞栎林（2005.33粒/m²）＞马尾松林（1045.33粒/m²）。不同的植被恢复模式种子库相比较,物种丰富度的顺序为板栗林（23）=针阔混交林（23）＞栎林（21）＞马尾松林（20）＞柑橘林（16）=竹林（16）＞茶林（14）＞坡耕地（11）,而多样性指数顺序为:针阔混交林（3.19）＞栎林（3.17）＞马尾松林（3.12）＞竹林（3.05）＞板栗林（3.02）＞柑橘林（2.72）＞茶林（2.42）＞坡耕地（2.21）。8个林分两两间种子库组成成分相似性变化范围为37.50～86.67,但从总体上看并未表现出较大的异质性。其中坡耕地（参照）与其他植被恢复模式的相似性最小,板栗林、栎林、柑橘林的相似性最大。大多数植被恢复模式中,种子库萌发种子组成与地面原有物种有一些相似。各植被恢复模式中,针阔混交林物种多样性恢复最快,而柑橘林、茶林等群落结构相对较为简单。受人为干扰较少的针阔混交林、马尾松林、栎林、板栗林等植被恢复模式土壤种子库中虽然种子数量不多,但其物种丰富度、物种多样性等指标均优于其它退耕还林模式的土壤种子库,并且在草本植物占优势的前提下,前者种子库中乔、灌、草生活型的物种比例均优于其它模式土壤种子库。从三峡库区退耕还林各植被恢复模式的生物多样性维持和保护来讲,马尾松、针阔混交林是该地区较好的生态林恢复方式,竹林和柑橘是较好的经济林模式。2.各植被恢复模式林地,随着土层深度的增加,土壤容重也随之增大,土壤容重均值大小顺序为:板栗林(1.865g·cm^-3)＞马尾松林(1.815g·cm^-3)＞栎林(1.795g·cm^-3)＞柑橘(1.725g·cm^-3)＞针阔混交林(1.53g·cm^-3)＞茶林(1.51g·cm^-3)＞坡耕地(1.46g·cm^-3)＞竹林(1.375g·cm^-3)。土壤孔隙度均表现为A层高于B层,总孔隙度均值大小顺序为:竹林（44.885%）＞茶林（44.44%）＞针阔混交林（44.345%）＞坡耕地（44.3%）＞栎林（33.7%）＞柑橘林（32.25%）＞马尾松林（30.4%）＞板栗林（29.7%）。各种植被恢复模式有效蓄水量大小依次为竹林(510.34t·hm^-2)＞针阔混交林(307.30t·hm^-2)＞板栗林(305.80t·hm^-2)＞坡耕地(274.95t·hm^-2)＞马尾松林(261.80t·hm^-2)＞柑橘林(255.75t·hm^-2)＞茶林(242.00t·hm^-2)＞栎林(178.00t·hm^-2)。土壤初渗速率在0.03mm·min^-1～4.43 mm·min^-1之间,稳透速率为0.03 mm·min^-1～2.96 mm·min^-1。A层栎林和马尾松林的稳透速率最高,坡耕地最低;B层竹林最高,马尾松林和针阔混交林最低。3.3种有枯落物层的林分枯落物单位面积储量依次为:栎林(16.88t·hm^-2)＞马尾松林(13.24t·hm^-2)＞针阔混交林(6.88t·hm^-2)。枯落物单位质量最大持水量依次为针阔混交林(2863.0g·kg^-1)＞栎林(2696.9g·kg^-1)＞马尾松林(1796.0g·kg^-1)。枯落物的持水量（失水量）随浸泡时间（失水时间）的增加而增加,初期增长幅度较大,后期逐渐平稳。持水量（失水量）与浸泡时间（失水时间）呈对数关系。持水率（失水率）与浸泡时间（失水时间）呈幂函数关系。4.各林地的水土保持效果比还林前的坡耕地有了明显的改善,地表径流量呈明显的减少趋势,其中针阔混交林模式地表径流量最小,为220.7 m³/hm²,比坡耕地减少了86.42%,其次为板栗林、栎林、柑橘林、马尾松林、竹林和茶林,平均较坡耕地减少82.04%。径流系数变化范围在0.0195～0.0253之间,平均为0.0215,与坡耕地径流系数相比减少了83.72%。退耕还林后林地土壤的侵蚀模数均呈现明显减小趋势,减小范围为1608.87～1876.66t/km²·a^-1,以竹林模式土壤侵蚀模数最小,为85.8t/km²·a^-1,较坡耕地减少95.6%;其次为针阔混交林,较坡耕地减少93.1%;茶林模式土壤侵蚀量最大,352.63 t/km²·a^-1。研究区内土壤大多呈酸性,土壤有机质、N、P、K、交换性Ca²⁺、Mg²⁺量等营养元素含量与坡耕地对照样地相比较均有较大的提高,其中有机质含量栎林的提高最多,达到189%;水解氮马尾松林提高最多,为192%;全氮是板栗林提高最多,达到354%;速效磷则是马尾松林提高最多,为129%;全磷则是柑橘林提高最多,达到810%;速效钾板栗林提高最多,为176%;交换性阳离子变化幅度并不很大。5.利用主成分分析法,选取有机质、水解氮、全氮、速效磷、全磷、速效钾、交换性钙量、交换性镁量、pH值、容重、非毛管孔隙度共11个因子作为主成分分析法的评价指标,对不同植被恢复模式土壤质量进行评价。7种模式的土壤质量指数分别为:马尾松林（1.6170）＞板栗林（1.0239）＞栎林（0.7764）＞针阔混交林（0.2902）＞柑橘林（-0.3007）＞竹林（-0.7028）＞茶林（-1.1719）＞坡耕地（-1.5320）。不同的退耕还林模式相比,人为干扰较少的马尾松林等模式土壤质量明显优于茶林、竹林等受人类耕作影响较大的模式。在库区应该大力推荐的生态林植被恢复模式为马尾松林和板栗林,经济林为柑橘和竹林。更多还原

【Abstract】 Based on former studies,we chose seven typical vegetation restoration models （chestnut plantation,oak forest,citrus plantation,masson pine forest,tea plantation, bamboo forest and mixed conifer and broadleaved forest） in Lanlingxi small watershed in the Three Gorges Reservoir Area as study subjects,choosing slope land as reference.A detailed study on ecological benefit assessment of conversion of farmland to forest in different vegetation restoration models in the study area was made and principal results were as follows:1.The herb plants were the main components of the numbers of species and individuals in soil seed bank.The size order of density in soil seed bank was:slope land（12042.67grain/m²）,citrus plantation（10160 grain/m²）,mixed conifer and broadleaved forest（5605.33 grain/m²）,bamboo forest（3653.33 grain/m²）,chestnut plantation（3642.67 grain/m²）,tea garden（3626.67 grain/m²）,oak stand（2005.33 grain/m²）,masson pine forest（1045.33 grain/m²）.Species richness of soil seed banks in different vegetation restoration models was caculated,and the result was as follows: chestnut plantation（23）,mixed conifer and broadleaved forest（23）,oak stand（21）, masson pine forest（20）,citrus plantation（16）,bamboo forest（16）,tea garden（14）,slope land（11）.The diversity of soil seed banks was in order of mixed conifer and broadleaved forest（3.19）,oak stand（3.17）,masson pine forest（3.12）,bamboo forest（3.05）,chestnut plantation（3.02）,citrus plantation（2.72）,tea garden（2.42）,slope land（2.21）.The similarity range of composing species between every two patterns was 37.50～86.67,but overall didn’t exhibit a large heterogeneity.Among them,the similarity between slope land and other patterns was at minimum,but the similarity among chestnut plantation, oak stand and citrus plantation was larger than others.In these different vegetation restoration models,there were some similar species between soil seed banks and ground vegetation.In different vegetation restoration models,diversity of mixed conifer and broadleaved forest was restored rapidly,but the community structures of citrus plantation,tea garden were relatively simple.Although seed amount in models under less human disturbance such as mixed conifer and broadleaved forest,masson pine forest and oak stand was not large,their species richness and species diversity were larger than the others.On the premise of herb plants accounting for 88.1%,proportional composition of life forms of species in the former patterns was better than others.According to the maintenance and conservation of biodiversity of different vegetation restoration models in returning farmland to forest project in the Three Gorges Reservoir Area,masson pine forest and mixed conifer and broadleaved forest were better ecological forest models,and bamboo forest and citrus plantation were better economic forest models.2.In different vegetation restoration models,soil bulk density tended to increase with soil depth increasing.The order of soil bulk density was:chestnut plantation (1.865g·cm^-3),masson pine forest(1.815g·cm^-3),oak stand(1.795g·cm^-3),citrus plantation(1.725g·cm^-3),mixed conifer and broadleaved forest(1.53g·cm^-3),tea garden (1.51g·cm^-3),slope land(1.46g·cm^-3),bamboo forest(1.375g·cm^-3).The soil porosity sequence in size order was:bamboo forest（44.885%）,tea garden（44.44%）＞mixed conifer and broadleaved forest（44.345%）,slope land（44.3%）,oak stand（33.7%）,citrus plantation（32.25%）,masson pine forest（30.4%）,chestnut plantation（29.7%）.The order of efficient water storage capacity was:bamboo forest(510.34t·hm^-2), mixed conifer and broadleaved forest(307.30t·hm^-2),chestnut plantation(305.80t·hm^-2), slope land(274.95t·hm^-2),masson pine forest(261.80t·hm^-2),citrus plantation (255.75t·hm^-2),tea garden(242.00t·hm^-2),oak stand(178.00t·hm^-2).The stable percolation rate was 0.03mm·min^-1 to 4.43mm·min^-1,the stable percolation rate was between 0.03 mm.min^-1 and 2.96 mm·min^-1.The stable percolation rate of oak stand and masson pine forest was the highest in A layer;and slope land was the lowest as 0.96 mm·min^-1.In B layer,the stable percolation rate of bamboo forest was the highest (1.02mm·min^-1);masson pine forest and mixed forest of conifers and broad-leaved trees were the lowest(0.03 mm·min^-1).3.The amount of litter of the three forest types（oak stand,masson pine forest,mixed forest of conifers and broad-leaved trees） in per unit area were 16.88 t·hm^-2,13.24 t·hm^-2 and 6.88 t·hm^-2,respectivly.The maximum water-holding capacity of the three patterns in per unit weight was:mixed forest of conifers and broad-leaved trees(2863.g·kg^-1),oak stand(2696.9g·kg^-1),masson pine forest(1796.0g·kg^-1).The relationship between the water capacity（water-losing capacity） of litter production and immersion time （water-losing time） was a logarithm function.The relationship between the water absorption speed（water losing speed） of litter production and immersion time （water-losing time） was a power function.4.Compared with slope land,soil and water conservation effects of different vegetation restoration models had been improved obviously,and the surface runoff trended to decrease.Among them,the surface runoff in the pattern of mixed conifer and broadleaved forest was the minimum（220.7 m³/hm²）,which was decreased by 86.42% compared with slope land.The range of runoff coefficients of different models was 0.0195 to 0.0253,average being 0.0215,which was decreased by 83.72%compared with slope land.The soil erosion modulus in different vegetation restoration models trended to decrease and the range was 1608.87 t/km²·a^-1 to 1876.66t/km²·a^-1.The soil erosion modulus in bamboo forest was the minimum(85.8 t/km²·a^-1),which was decreased by 95.6%compared with slope land.Next came mixed conifer and broadleaved forest, which decreased by 93.1%.The maximum was tea garden(352.63 t/km²·a^-1).The research showed that most of the soil in study areas was a bit acidic,and nutrient content of soil organic matter,N,P,K,exchangeable Ca²⁺ and exchangeable Mg²⁺ trended to increase compared with slope land.The massion pine forest had the biggest increase in hydrolytic nitrogen（192%） and available phosphorus（129%）.The chestnut plantation had the biggest increase in total nitrogen（354%）,available potassium （176%） and soil organic matter（189%）.The citrus plantation had the biggest increase in total phosphorus（810%）.Variation range of exchangeable cation in different patterns was limited.5.Eleven factors(soil organic matter,hydrolytic nitrogen,total nitrogen,available phosphorus,total phosphorus,available potassium,exchangeable Ca²⁺,exchangeable Mg²⁺,pH,bulk density and non capillary porosity) were chosen as the evaluation index of the principal component analysis to evaluate the soil quality in different vegetation restoration models.Compared with the soil of slope land,the soil quality in seven models were better than slope land.The soil quality index of different models was respectively: masson pine forest（1.6170）,chestnut plantation（1.0239）,oak stand（0.7764）,mixed conifer and broadleaved forest（0.2902）,citrus plantation（-0.3007）,bamboo forest （-0.7028）,tea garden（-1.1719）,slope land（-1.5320）.The soil quality of models under less human disturbance such as chestnut plantation and masson pine forest was obviously better than those influenced by cultivation activities.So recommended ecological forest models in research area were masson pine forest and chestnut plantation,recommended economic forest models were citrus plantation and bamboo forest.更多还原