中国水土保持科学2017,Vol.15Issue(4):25-34,10.DOI:10.16843/j.sswc.2017.04.004
2种草本植物根系对长汀县崩岗洪积扇土壤水分状况的影响
Effects of two types of herb plants' roots on soil moisture in the alluvial soil in Changting County
摘要
Abstract
[Background] Alluvial is an important part of collapsing gully,as a type of disturbed soil,alluvial feature high contents of gravel,sand,and loose materials,so that they are often weak in structure,low in cohesion and high in erodibility.Alluvial may bring hazards to ecological environment.Plant is the key to control soil and water loss.Planting vegetation on the alluvial can effectively reduce erosion and water conservation,increase stability of soil structure and soil water storage ability.[Methods] Two typical herbs Pennisetum sp.(deep-root system) and Paspalum wettsteinii (shallow-root system),which were planted in the alluvial soil,were chosen as the research object to analyze the effects of plants' root systems on the alluvial soil moisture.Soil samples were collected by layering sampling along the root,and soil physical properties including soil bulk density,porosity and maximum moisture capacity etc.were tested by cutting ring method,which were used to calculate the soil water storage capacity.In addition,the roots were separated from undisturbed soil samples,which were collected by big cutting ring (the inner diameter of 9.8 cm and 5.0 cm high).Root system parameters such as root length density,total surface area,total volume,average diameter,etc.were measured by WinRHIZO root analysis system.[Results] The indexes of root system characteristics of Pennisetum sp.and P.wettsteinii decreased with the increase of soil depth,all root indexes of Pennisetum sp.were greater than those of P.wettsteinii.Vegetation cover decreased the soil bulk densities compared to bare land,also the soil total porosity and capillary porosity of soil with vegetation covers were greater than those of bare land,decreasing with the increase of soil depth.In addition,plant root system increased the soil saturated water storage and capillary water storage,which were significantly different from those of bare land,so that showed the soil with root systems had a better effect on the soil water conservation than that of bare soil.In top soil,compared with Pennisetum sp.,P.wettsteinii greatly increased soil porosity and strengthened water-holding capacity more,the situation was on the contrary in deep soil.The capacity of root system to improve soil properties mainly depended on root length density and root total surface area,the roots whose diameters were smaller than 0.5 mm were the main effective factor of the soil moisture.[Conculsions] In summary,planting vegetation in the alluvial soil improves the soil structure,enhances the soil porosity,and raises the soil water storage capacity,thus the roots of vegetation are helpful in water conservation.In addition,these two measures are worthy of reference and popularization in the eroded area.关键词
洪积扇/巨菌草/宽叶雀稗/根系/土壤水分Key words
alluvial soil/Pennisetum sp./Paspalum wettsteinii/root systems/soil moisture分类
农业科技引用本文复制引用
何恺文,黄炎和,蒋芳市,林金石,程子捷,张凯,谢伟昆,黄兆祥..2种草本植物根系对长汀县崩岗洪积扇土壤水分状况的影响[J].中国水土保持科学,2017,15(4):25-34,10.基金项目
国家科技支撑计划项目“中小型崩岗区的生态修复技术与示范”(2014BAD15B0303) (2014BAD15B0303)
国家自然科学基金“花岗岩崩岗土体胶结物质与抗剪强度的关系研究”(41571272) (41571272)
福建省自然科学基金“组合指纹法分析强度侵蚀小流域产沙与迁移规律”(2015J01156) (2015J01156)