农业景观中非农景观要素结构特征对植物物种多样性的影响——以封丘县为例

农业景观中的非农生境对维持与提高农业景观的生物多样性具有非常关键的作用。为了探究非农生境的相关结构属性对农业景观中植物物种多样性的影响,选择黄河下游平原区的封丘县为研究区域,对研究区内42个样点的非农生境进行植物多样性调查,并对各个样点周围1 km范围内的非农景观要素进行了提取,分析不同非农生境中植物物种组成及其景观要素的构成、结构及空间配置对植物物种多样性的影响。研究结果表明:不同类型的非农生境中,物种组成共有种相对较多,特有种或指示种较少;林地与树篱具有相对较高的物种多样性,以沟渠为生境的植物物种组成与其它两种生境类型相比存在明显差异;林地与树篱/沟渠的组成比例相当时,植物物种丰富度最高;景观指数对不同非农生境中的植物物种具有明显影响,景观破碎化及人为干扰指数的影响较为显著。未来在对本区域内农业景观进行结构优化的过程中,应从非农景观要素的改造入手。通过调整和设置非农景观要素的不同类型及比例、合理改造其结构与空间配置,为最终实现农业景观的有效管理与可持续健康发展奠定重要的研究基础。

Non-agricultural landscape structure and the effect on plant species diversity in agricultural landscapes: a case study in Fengqiu County

Non-agricultural habitat is an important part of the agricultural landscape, and its complex structure and function play a vital role in maintaining and improving the biodiversity of the agricultural landscape. However, there is widespread evidence that the highly intensive global development of modern agriculture has led to the disappearance of many non-agricultural habitats, resulting in a simpler agricultural landscape. Therefore, the agro-ecosystem functions and services have been seriously damaged. Consequently, for the sustainable development of agriculture, studying the relationships between agricultural productivity and biodiversity, and landscape pattern and ecosystem functions and services are fundamental. To explore the structural attributes of non-agricultural landscape elements and the effect on plant species diversity in typical agricultural landscapes, we established a study area and developed 42 plots in Fengqiu County, Henan Province, which is a typical agricultural region in the lower reaches of the Yellow River. Within these plots, the vegetation in non-agricultural habitats (artificial forests, hedges, and ditches) was investigated using the Braun-Blanquet method. Based on remote sensing imagery and landscape pattern analysis, we extracted and classified the non-agricultural habitats of each sample within 1 km using ArcGIS 10.0, and analyzed the composition, structure, and spatial configuration of non-agricultural landscape elements. The results showed that 186 species belonging to 50 families and 164 genera were found in the study area, and six dominant families (Compositae, Gamineae, Leguminosae, Cruciferae, Labiatae, and Solanaceae) account for 51.6% of all species. The species diversity of artificial forests and hedges was relatively high, whereas the species composition of the ditches was different to the other habitats. In different types of non-agricultural landscape structure, the highest species richness of plants was found where the proportion of artificial forests was similar to hedge/ditches. The landscape metrics directly affect plant species diversity in different non-agricultural habitats, and the influence of landscape fragmentation and human disturbance is significant. From the results, to increase the quantity and quality of non-agricultural habitats in agricultural landscapes in the future, we should transform the non-agricultural landscape elements. New non-agricultural habitats should be developed, and the proportion of different types of habitats should be increased by adjusting the spatial structure and configuring different landscape elements. This would enhance the effective management and sustainable development of the agricultural landscape in the future.