喀斯特地区不同退耕还林土壤理化特性分析——以贵州省修文县为例 摘要为揭示喀斯特地区不同退耕还林的土地利用方式对土壤理化属性演变的影响，本研究以贵州省修文县石漠化退耕还林区为研究区，进行实地调查，对不同类型的土壤进行采样分析。运用数理统计方法，以坡耕地为参照样地，从物理属性和化学属性两个角度来研究梨树、滇柏、刺槐3种不同退耕还林模式的土壤剖面（0-20cm、20-40cm）理化属性特征。研究结果表明：3种不同的退耕还林模式的土壤理化属性存在显著差异，并进行理化属性变化的原因分析。与参照样地(坡耕地)相比，修文县退耕还林15年后，退耕为梨树后土壤容重呈降低的趋势，土壤酸化严重，土壤中的P和K的含量降低。退耕为滇柏会使土壤的容重有所下降，使土壤的PH偏碱性，对N、P含量变化不明显。植刺槐使土壤中的容重升高，土壤中＞2mm石砾含量升高，使土壤中的N、P和有机质的含量降低。滇柏对研究区退耕还林土壤的改良效果最好，建议作为贵州省修文县未来退耕还林推广植被。71856

毕业论文关键词：退耕还林  土壤理化属性特征  修文县

Different characteristics of returning farmland to forest soil physical and chemical properties, Karst area in Guizhou Province by the county as an example

Abstract To reveal different returning farmland to forest land use on soil physical and chemical properties change in Karst region,this study takes farmland to forest area in Guizhou as the research area,and conducts field investigation to analysis of different types of soil samples。Using the mathematical statistics method and taking farmland as reference sample。Study three different modes (pear, Yunnan parker, acacia parker )of returning farmland to forest soil profile (0 ~ 20 cm, 20 ~40 cm) characteristics of physical and chemical properties from physical properties and chemical properties 。The results showed that there were significant differences in Three different model of returning farmland to forest soil physical and chemical properties 。Conducting the analysis of the causes of physical and chemical properties change。Compared with the reference sample (slope) by Xiuwen County , the soil bulk density of returning farmland to pear trees had a trend of decrease after 15 years。Soil acidification is serious and the content of P and K in the soil decrease。Returning farmland to Yunnan cypress can make the soil bulk density decreased, soil PH alkaline,N and P content change is not obvious。Planting acacia can raise the soil bulk density and soil (> 2 mm )gravel content, make the content of N, P and organic matter in the soil decreased。Yunnan cypress is the best effect on returning farmland to forest in the studied area soil improvement ,Suggested as future promotion on returning farmland to forest vegetation by Xiuwen County in Guizhou Province。

Key words: returning farmland to forest  Characteristics of soil physical and chemical properties   Xiuwen County

目  录

摘  要 I

Abstract II

目  录 III

图清单 IV

表清单 IV

1 绪论 1

1。1 目的意义 1

1。2 国内外研究进展 1

1。3 研究思路与技术路线 2

2  研究区概况 2

2。1研究区贵州省修文县区位图 3

2。2采样区不同植被种植类型土壤概况