黄河下游平原农业景观中非农生境植物多样性

Plant species of the non-agricultural habitats in the lower reaches of the Yellow River plain agro-landscape

农业景观中的自然、半自然生境及其上的植物群落对维持农业生态系统功能意义重大。为了解黄河下游典型平原农业景观中非农生境植物多样性特征,在对研究区景观格局分析的基础上,使用典型样地法对区域内农业景观中主要自然、半自然生境(包括林地、树篱、田间道路、沟渠等)进行调查。结果显示:研究区总体上为农业景观,居民点和林地斑块散布其间;区内植物科的地理分布以世界分布和泛热带分布为主,属的地理成分复杂,具有中国15个种子植物属分布区类型中的13个,以温带分布、世界分布和泛热带分布为主,总体上以广布种为主,优势科属明显,缺少特有种;林地和树篱具有较高的物种丰富度和多样性,沟渠和林地的物种均匀度和群落盖度最高,田间道路上群落组成的变化幅度和分化程度最大(β多样性指数最高);林地、树篱和田间道路等生境间的群落相似性极高,但其群落盖度和优势种组成具有显著差异,沟渠作为一种特殊生境与其他生境间相似性较低。研究表明,在黄河下游平原农业景观中,林地和树篱在物种多样性维持中作用较大,沟渠为水生和湿生植物提供了庇护所,不同生境间极高的群落相似性仅是物种组成名录的反映,而其生态功能存在显著差异。未来区内的生物多样性保护应重在生态系统功能和服务的维持及提高,而如何进行景观要素配置,才能兼顾农业生产力的可持续性和生态系统功能维持,尚需进一步探讨。

The stabilization and sustainability of the agro-ecosystem functions and services are the basis of human survival and human well-being. Natural and semi-natural habitats of the agro-landscape, as well as the associated plant communities, have important ecological functions for the agro-ecosystem. Construct one of agro-landscape is very helpful to promote agricultural productivity and the protect biodiversity and ecosystem functions. However, the distributional and compositional patterns of plant species in agro-ecosystem functions are still unclear. In order to better understand the landscape patterns and plant community characteristics of the non-agricultural habitats in the lower reaches of the Yellow River plain, a total of 26 plots arranged in a grid were set up in Fengqiu county of Henan Province. Within these plots, the vegetation in natural and semi-natural habitats of the agro-landscape was investigated by using the Braun-Blanquet method. The surveyed habitats were mainly including the artificial forests, hedges, field roads, ditches. The results are as follows： （1） the study area is mainly dominated by agro-landscape, the residential area and forest patches are scattered in the agro-landscape; （2） the flora analysis showed that a total of 38 families, 107 genera, 127 species were founded in the study area. The cosmopolitan （15 families, 39.5%） and pantropic distribution （14 families, 36.8%） are mainly distribution types of the families. The complexly geographical composition of the genera comprises 13 of 15 distribution types of Chinese seed plants, in which the temperate, cosmopolitan and pantropic distribution are the dominated distribution types （71 genera, 69.84%）. In general, it is showed that the widespread species are dominating in the study area, and the dominant families and genera are obviously, but lack of endemic species; （3） the artificial forests and hedges have the highest species richness and diversity compared with the other kinds of non-agricultural habitats. Whereas the highest species evenness and coverage appeared in the ditches and artificial forests, and the field roads have highest variability and differentiation of the community composition （with a highest β-diversity index）; （4） the results about the community similarity analysis showed that the artificial forests, hedges and field roads have a very high similarity, by contrast, the ditches has a low similarity, the difference is mainly attributed to the special characteristic of it. However, the community similarity among different biotope was just the reflect of species list, the ecological functions of them are different obviously. According to the above results, we found that the artificial forests and hedges have an equally important role in species conservation of the agro-landscape of the lower reach of Yellow River plain, due to identical species diversity of them. while ditches provided a shelter for the hydrophytes and hygrophytes. Furthermore, if taking into account the maintenance of agricultural production and ecological functions under agro-landscape planning and management of the study area in the future, the construction of hedge corridors should be a good choice. For artificial forests it would be better to maintain higher species diversity to improve the ecological functions by appropriately transforming the forests＇ structure and species composition.Future studies are needed to examine how agricultural landscapes assemble processes maintain both agricultural productivity and ecosystem functioning.