论文部分内容阅读
贝壳堤生态系统具有典型性和脆弱性,土壤蓄水能力决定着贝壳堤系统的稳定性和植被生产力的高低.为阐明贝壳堤不同植被类型土壤蓄持水分能力及其影响因素,测定分析了贝壳砂土壤的基本物理参数、渗透性及土壤水分的温度响应特性,采用模糊数学隶属函数法评价了不同植被类型的土壤蓄水潜能.结果表明:酸枣林、杠柳林和草地能有效改善土壤通透性,土壤总孔隙度分别比裸地增加27.0%、19.3%和10.8%.在30℃和50℃恒温下,不同植被类型的土壤含水量随烘干时间的延长可分为土壤水分瞬变、渐变和平稳3个阶段.两种温度下,土壤饱和含水量、土壤达到恒重时间和失水率均表现为酸枣林>杠柳林>草地>裸地.Horton模型适宜模拟贝壳砂生境的土壤入渗特征,灌木林土壤入渗性能好于草地.杠柳林和酸枣林的稳渗速率分别比裸地增加27.1%和5.4%,而草地比裸地降低76.6%.反映土壤蓄持水分的主要指标一类是土壤容重和孔隙度,另一类是土壤粗砂粒、粉粘粒分布和稳渗速率.贝壳砂土壤蓄水潜能综合评价为灌木林好于草地,酸枣林强于杠柳林,而裸地较差.
Shell embankment ecosystem is typical and vulnerable, soil water storage capacity determines the stability of the shell embankment system and the level of vegetation productivity.In order to elucidate the capacity of soil holding moisture and its influencing factors in different types of shell embankment, The basic physical parameters and permeability of sandy soil and the temperature response of soil moisture were used to evaluate the soil water storage potential of different vegetation types by using the fuzzy mathematics membership function method.The results showed that the jujube forest, Permeability and soil total porosity increased by 27.0%, 19.3% and 10.8% respectively compared with the bare soil.When the water temperature was constant at 30 ℃ and 50 ℃, the soil moisture content of different vegetation types with the drying time could be divided into soil moisture transient , Gradual and stable in three stages.However, the saturated soil moisture content, the time to reach the constant weight and the soil water loss rate showed the jujube forest> barbarian forest> grassland> bare land under the two temperatures.Horton model is suitable for the simulation of the habitat of the shell sand Soil infiltration characteristics and soil infiltration of shrubbery were better than that of grassland. The steady infiltration rate of barbarian forest and jujube forest increased by 27.1% and 5.4% respectively compared with bare land, while that of grassland decreased by 76.6% compared with bare land. One of the main indicators of soil moisture storage is soil bulk density and porosity, and the other is the distribution of coarse grit and silt, and the steady infiltration rate.The comprehensive evaluation of soil water storage potential of scallop sandy soil is that shrub forest is better than grassland and jujube forest strong In the willow forest, and bare ground less.