摘要
亚高山森林自采伐后,迹地上灌木迅速扩张形成的"灌丛岛"对土壤肥力、幼苗更新等有重要作用.为揭示川西亚高山采伐迹地上灌丛岛土壤持水性能及其影响因素,选择亚高山采伐迹地上4种典型灌丛(高山柳、鲜卑花、绣线菊和杜鹃)为研究对象,以草丛为对照,测定灌丛岛下土壤持水性能,并结合灌丛特征和土壤理化性质进行分析,结果显示:(1)采伐迹地上灌丛岛的形成明显影响土壤持水性能,杜鹃和高山柳灌丛土壤持水量与草丛差异显著.其中杜鹃灌丛土壤持水量和毛管持水量最高,分别较草丛增加了24.5%和23.0%;高山柳灌丛土壤非毛管持水量最高,较草丛增加了51.02%.(2)灌丛岛的形成也影响了土壤容重和孔隙度等物理特征,其效应大小依赖于灌丛岛类型.如与草丛相比,杜鹃与高山柳灌丛土壤容重分别显著降低25.7%和18.6%,总孔隙度分别显著增加5.4%和5.2%.(3)通过结构方程模型分析发现,灌丛岛土壤持水性能除受土壤物理结构特征(如容重和孔隙等)影响外,也与灌丛岛类型和大小等因素有关.因此,亚高山采伐迹地灌丛岛的形成通过影响土壤理化性质,进而导致土壤的持水性能差异;研究结果可为评估亚高山森林生态系统土壤生态功能提供科学参考.
Cutting of subalpine forests leads to the formation of"shrub islands"by the rapid expansion of shrubs on the slash.Shrub islands play an important role in soil fertility and seedling regeneration.However,there have been few studies on the ecological functions of shrub islands,such as soil water holding capacity,after their formation in high altitude areas.In this study,four typical shrubs(Salix cupularis,Sibiraea angustata,Spiraea alpina,and Rhododendron nivale)were selected as the research objects,and tussock was selected as the control to determine the water holding capacity of soil in shrub islands.At the same time,we combined the water holding capacity,shrub characteristics,and soil physicochemical properties to determine the soil water holding capacity and influence factors of shrub islands in the subalpine cutting slash.The results showed that(1)the formation of the shrub island significantly affected the soil water holding capacity,and the soil water holding capacity of R.nivale and S.cupularis was significantly different from that of tussock.Moreover,the soil water holding capacity and capillary water holding capacity of R.nivale were the highest,increasing by 24.5%and 23.0%,respectively,compared with those of tussock.The non-capillary water holding capacity of S.cupularis was the highest,increasing by 51.02%compared with that of tussock.(2)The formation of shrub islands also affected soil physical characteristics,such as bulk density and porosity,and the effect depended on the type of shrub island.For example,compared with tussock,the soil bulk density of R.nivale and S.cupularis decreased by 25.7%and 18.6%,respectively,and the total porosity increased by 5.4%and 5.2%,respectively.(3)By analyzing the structural equation model,it was found that the soil water holding capacity of the shrub islands was not only affected by soil physical structure characteristics,such as bulk density and porosity,but was also related to the type and size of the shrub islands.In summary,these results indicate that the formati
作者
何露露
庞学勇
HE Lulu;PANG Xueyong(CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province,Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdu 610041,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2021年第3期632-638,共7页
Chinese Journal of Applied and Environmental Biology
基金
国家重点研发计划项目(2017YFC0505002)
国家自然科学基金项目(31770658)
中国科学院重点部署项目(KFZD-SW-427,XDA20020401)
四川省科技计划项目(2018SZDZX0030)资助。
关键词
灌丛岛
土壤持水
土壤结构
影响因素
亚高山森林
shrub island
water holding capacity
soil structure
influence factor
subalpine forest
