石羊河下游非地带性土壤对黑果枸杞(Lycium ruthenicum)种群空间分布格局影响机制

Lycium ruthenicum is a desert plant with special nutritional and medicinal values growing in the desert regions in Shiyang River Basin in northwest China. It is a pioneering species in Shiyang River Basin. The natural shrub communities consisting of Lycium ruthenicum played an important role in protecting the oasis in the downstream of Shiyang River Basin. It is also one of the important economic plant resources. In this study, Lycium ruthenicum communities as well as the soil were observed, the distribution pattern, age structure, interrelations among Lycium ruthenicum communities in different habitats and developmental stages, correlation between different soil habitat and the distribution pattern of Lycium ruthenicum are analyzed through the quantitative analysis, typical pattern analysis, spatial point pattern analysis and the methods such as clustering and ordering. The dynamic situation of population distribution is illustrated, and the changing trend is forecasted. The effects of soil on the spatial distribution pattern of Lycium ruthenicum are analyzed to determine whether the survival and variation of Lycium ruthenicum is adapting the or depending on the soil. The spatial distribution pattern of Lycium ruthenicu is raised, and the mechanism of soil affecting the distribution of Lycium ruthenicu is illustrated. The study will provide a theoretical reference for protecting Lycium ruthenicum community and the artificial plantation. It is of important significance for the study of the adaptive mechanisms and artificial plantation of Lycium ruthenicum, as well as the protection and utilization of ecological vegetation in the desert region.

黑果枸杞（Lycium ruthenicum）是我国西北荒漠区一种具有特殊营养和药理用途的植物，是石羊河下游植被的建群种之一，组成的天然灌木林对保障石羊河流域下游的绿洲生态安全起着至关重要的作用，也是重要的灌木草场和生物资源。本项目通过对石羊河下游黑果枸杞种群和土壤调查及室内实验，应用种群数量分析法、经典格局分析法、空间点格局法和聚类与排序等方法，分析其分布格局、年龄结构、种群关联度和不同土壤生境与黑果枸杞种群空间分布格局关系，阐明石羊河下游黑果枸杞种群分布及动态，预测黑果枸杞种群变化趋势；分析土壤在黑果枸杞种群空间格局形成的作用，确定种群生存和变化是适应土壤还是依赖土壤；提出黑果枸杞种群空间格局模型，阐明石羊河下游黑果枸杞种群分布格局的土壤影响机制。为科学制定黑果枸杞种群保护和人工种植提供理论依据，对今后研究黑果枸杞种群的环境适应机制、人工种植以及区域内生态植被保护和利用具有重要意义。

黑果枸杞（Lycium ruthenicum）是我国西北荒漠区一种具有特殊营养和药理用途的植物，是石羊河下游植被的建群种之一，组成的天然灌木林对保障石羊河流域下游的绿洲生态安全起着至关重要的作用，也是重要的灌木草场和生物资源。本项目通过对石羊河下游黑果枸杞种群和土壤调查及室内实验，应用种群数量分析方法、经典格局分析方法、空间点格局法和聚类与排序方法，分析其分布格局、年龄结构、种群关联度和不同土壤生境与黑果枸杞种群空间分布格局关系，阐明石羊河下游黑果枸杞种群分布及动态，预测黑果枸杞种群变化趋势；分析土壤在黑果枸杞种群空间格局形成的作用，提出黑果枸杞种群空间格局模型，阐明石羊河下游黑果枸杞种群分布格局的土壤影响机制。为科学制定黑果枸杞种群保护和人工种种植提供理论依据。项目圆满完成了各项研究任务，实现了预期目标。研究结果表明，1）研究区有30种植物，隶属8科27属，大多数为单科单属；群落丰富度和生态优势度指数较高，多样性指数偏低，群落间均匀度指数相差不大，植物物种分布极其不均匀，植被稳定性较低。2）在沙地和盐碱地中黑果枸杞的个体数量较多，聚集程度相对较高，黑果枸杞表现出以母株为中心的聚集分布繁殖策略；砾石样地中黑果枸杞的个体数量较少，由于受到生态挤压，所以有一定的随机趋势。在不同发育阶段，黑果枸杞种群多以聚集分布为主，随着龄级的增大，黑果枸杞种群呈现出由聚集分布趋向均匀分布的变化趋势。3）不同立地类型样地中土壤含水量随土层加深呈逐渐增加的趋势；各类型样地中细砂粒含量最高；土壤中大部分营养元素“表聚现象”明显，随着土层深度的增加，土壤微生物生物量和酶活性逐渐减小。4）过氧化氢酶、磷酸酶、全氮、全磷、pH值、电导率、HCO3-、SO42-是影响该地区黑果枸杞群落植物分布的关键因子，其中pH值是对群落物种多样性具有较大影响的土壤因子。