川西亚高山/高山森林土壤养分动态及其对季节性冻融的响应

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 川西亚高山-高山森林土壤养分动态及其对季节性冻融的响应 DOI: 10.5846/stxb201312303063 作者: 作者单位: 四川农业大学,四川农业大学;绵阳师范学院,四川农业大学,四川农业大学 作者简介: 通讯作者: 中图分类号: S718.5 基金项目: 国家自然科学基金项目(31170423, 31270498); 国家"十二五"科技支撑计划(2011BAC09B05); 四川省杰出青年学术与技术带头人培育项目(2012JQ0008, 2012JQ0059); 高等学校博士学科点(博导类)专项科研基金(20105103110002)项目 Dynamics of soil nutrients and their response to seasonal freeze-thaw in the subalpine-alpine forests of western Sichuan Author: Affiliation: Key Laboratory of Ecological Forestry Engineering,Institute of Ecology Forestry,Sichuan Agricultural University,Key Laboratory of Ecological Forestry Engineering,Institute of Ecology Forestry,Sichuan Agricultural University;Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University,Key Laboratory of Ecological Forestry Engineering,Institute of Ecology Forestry,Sichuan Agricultural University,Key Laboratory of Ecological Forestry Engineering,Institute of Ecology Forestry,Sichuan Agricultural University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为深入了解川西亚高山-高山森林冬季生态学过程,于2008年11月-2009年10月,在土壤冻结初期、冻结期和融化期及植被生长季节,研究了不同海拔(3582 m、3298 m和3023 m)岷江冷杉林土壤养分动态及其对季节性冻融的响应。3个海拔森林土壤冬季具有较高养分含量,且随土壤冻融过程不断变化。土壤有机层可溶性碳和氮、铵态氮、硝态氮含量在冻结初期显著增加后快速降低,并随融化过程迅速增加后再次降低,而土壤可溶性碳和氮、硝态氮含量在冻结期变化不明显,铵态氮显著增加。矿质土壤层可溶性碳和氮、铵态氮含量也在冻结初期显著增加后降低,而土壤可溶性氮、铵态氮和硝态氮在冻结期显著增加,并在融化期经历一个明显的含量高峰。海拔和土层的交互作用显著影响土壤可溶性碳和硝态氮含量,土壤养分含量与土壤温度的相关性随海拔差异而不同。这表明季节性冻融期是土壤生态过程的重要时期,土壤冻融格局显著影响川西亚高山-高山森林土壤养分动态。 Abstract:Soils in subalpine and alpine ecosystems during winter experience extensive snow cover, freezing, thawing, and freeze-thaw cycle with air temperatures fluctuating above and below 0 ℃. Such conditions have profound repercussions on soil nutrient availability, microbial biomass, and enzyme activity in subalpine and alpine ecosystems during winter, yet systemic studies of these ecosystems are lacking. In order to deeply understand winter ecological processes in the subalpine and alpine forests of western Sichuan, three fir (Abies faxoniana) forests including primary fir forest at 3582 m altitude, fir and birch mixed forest at 3298 m altitude, and secondary fir forest at 3023 m altitude were chosen as study subjects. Soil was collected at different stages: at the onset of the soil freezing period, the soil frozen period, the soil thawing period, and the growing season from November 2008 to October 2009. Concentration of dissolved carbon and nitrogen, NH4+-N, and NO3--N were measured in each soil sample. Compared to the growing season, the content of measured nutrients was relatively high during winter in all sampled forests. Moreover, the dynamics of the measured soil nutrients changed with the processes of the soil freeze-thaw cycle. In the soil organic layer, the amount of dissolved carbon and nitrogen, NH4+-N, and NO3--N significantly increased followed by a decrease in both the onset of the soil freezing period and the soil thawing period, whereas they showed little change in the soil frozen period, except for NH4+-N. In the mineral soil layer, the content of the measured nutrients also significantly increased and then decreased with the onset of the soil freezing period. However, the content of the dissolved nitrogen, NH4+-N, and NO3--N visibly increased in the soil frozen period, reaching a peak in the soil thawing period. Additionally, the interaction of the altitude and soil layer affected the amount of dissolved carbon and NO3--N. Correlation between the concentration of soil nutrients and soil temperature varied with the altitude. The results suggested that the seasonal freeze-thaw period is a crucial stage for ecological processes in the soil, and the soil freeze-thaw pattern significantly affects the dynamics of soil nutrients in the subalpine and alpine forests of western Sichuan. 参考文献 相似文献 引证文献