| 摘要: |
| 【目的】为了全面评价土地利用方式对喀斯特峡谷区土壤结构退化的影响。【方法】本文采用空间代替时间的方法，开展了不同土地利用方式对土壤水稳性团聚体分布特征及稳定性的研究。【结果】结果表明：1）不同土地利用方式均以>0.25mm粒径水稳性团聚体为主,其含量变化、MWD、GMD均表现为林草间作地>荒草地>退耕还草地>耕地；2）在不同土层中，不同土地利用方式土壤水稳性团聚体组成含量总体上随粒径的减小呈先增加后减少再增加的波浪型变化趋势，其中0~20cm土层，土壤各粒级水稳性团聚体含量分布及稳定性差异具有一定显著相关性，20cm~母质层差异不显著；3）5mm粒径团聚体成为土壤团聚体从微团聚体向大粒径团聚体团聚化过程中关键的临界点；4）GMD可以作为喀斯特峡谷区表层土壤及整个剖面土壤水稳性团聚体稳定性评价指标。【结论】综上可知，林草间作模式能够增强喀斯特峡谷区土壤结构的稳定性，对防止土壤结构退化具有重要作用。 |
| 关键词: 土地利用方式；水稳性团聚体；稳定性指标；喀斯特峡谷区 |
| DOI： |
| 分类号:S157.2 |
| 基金项目:喀斯特山区林草间作生态恢复过程中土壤质量演变规律及其评价-以贵州“晴隆模式”为例(31460133)；贵州科学院科技计划项目(黔科院字[2018]15号；黔科院人才[2019]07号)；贵州省财政专项资金项目“基于小流域基本单元的高标准农田建设标准、工程体系及效益评价” |
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| Effects of soil water-stable aggregates under different land-use patterns on Karst canyon region |
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xiaoshengyang
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Institute of Mountain Resources of Guizhou Province
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| Abstract: |
| 【Objective】In order to provide a theoretical basis for the comprehensive evaluation of the impact of land use on soil structure degradation in Karst Canyon region.【Method】The method of space instead of time was used to study the distribution characteristics and stability of soil water stable aggregates under different land use patterns.【Result】The results showed that the aggregate particle size of the four land use types was mainly＞0.25 mm, and their content changes, MWD and GMD were as follows: intercrop between forest and grass > barren grassland > returning farmland to grassland > cultivated land, FD value was opposite. In different soil layers，with the decrease of particle size, the content of soil water stable aggregates in different land-use patterns increased first, then decreased and then increased. The content distribution and stability difference of water stable aggregates in each particle class of soil have a certain significant correlation of the 0~20cm soil layer, but the difference in 20cm ~ parent material layer was not significant. In the process of soil aggregation from micro aggregate (< 0.25 mm) to large aggregate (> 5 mm), 5 mm particle size becomes the critical point. GMD can be used as an index for evaluating the stability of water-stable aggregates in the surface soil and the entire profile of the Karst canyon.【Conclusion】The intercrop between forest and grass model can enhance the stability of soil structure in Karst canyon region and play an important role in preventing soil structure degradation. |
| Key words: land-uses; water-stable aggregates; the stability indexes; karst canyon region |
