不同田边植草带对地表节肢动物群落结构的影响

Effects of different field border grass belts on the community structure of surface arthropods

在耕地边缘构建植草带有利于提升农田生物多样性及其生态系统功能。为探究田边植草带对地表节肢动物的影响及其建植方法,本研究以华北集约化农田为研究区,设置了由不同植物物种组成(分别为2、4、6种和8种植物组合)的人工植草带,通过陷阱法采集地表节肢动物并探究其群落结构特征对不同植物组合的响应。结果表明:本研究中地表节肢动物的优势类群为鼠妇、蜘蛛、蟋蟀和山蛩虫,其中鼠妇为最主要的节肢动物类群,数量占总数的52.06%,而人工植草带中鼠妇的数量及相对丰度均高于荒地和农田处理;与农田对照处理(CKN)相比,人工种植的植草带显著增加了地表节肢动物的多度和类群数,其中6种植物组合(T6)处理和8种植物组合(T8)处理的地表节肢动物的多度与类群数显著高于4种和2种植物组合处理(T4和T2);对地表节肢动物营养功能群分析发现,人工植草带显著提高了地表节肢动物各个营养功能群的数量,特别是食碎屑类动物和捕食类动物,其中T6处理和T8处理的食碎屑类动物分别为荒地处理(CKH)的3.9倍和4.9倍,为CKN处理的6.3倍和7.9倍,而T6处理的捕食类动物分别为CKH和CKN处理的1.6倍和1.9倍;通过相关性分析发现,地表植被大多数生物多样性特征都与地表节肢动物的多度和类群数呈正相关,其中植被的盖度、地上生物量和物种数与地表节肢动物的类群数呈极显著正相关,而植被的多度与地表节肢动物的多度呈负相关,植被的盖度与地表节肢动物的多度不相关。总体而言,在华北地区,构建人工植草带显著增加了地表节肢动物的丰度和丰富度,能够涵养更多的节肢动物,特别是食碎屑动物和捕食类动物,有利于提升农业生态系统中的养分循环功能和生物控害功能。在四种人工建植的植物组合处理中,按照6种植物组合和8种植物组合建植的田边植草带更有利于华北地区地表节肢动物群落的建立和农田生态系统功能的提升。

The grass-planted strips at the edge of arable land is conducive to enhancing farmland biodiversity and ecosystem function.To investigate the effects of field margin grass strips on surface arthropods and their construction methods,artificial grass strips consisting of different plant species(two,four,six and eight plant combinations,respectively)were set up in an intensive farmland in north China as the study area,and surface arthropods were collected by the trap method and their community structure characteristics were investigated in response to different plant combinations.The results showed that the dominant taxa of surface arthropods in this study were woodlice,spiders,crickets,millipedes,among which woodlice were the most dominant arthropod taxa,accounting for 52.06%of the total number,and the number and relative abundance of woodlice in the artificially planted grass belts were higher than that in uncultivated land and farmland treatments.Compared with farmland control treatment(CKN),the artificially planted grass belts significantly increased the abundance and number of groups of surface arthropods,with those in treatments T6 and T8 significantly higher than that of T4 and T2.T6 and T8 treatments had significantly higher abundance and number of groups of surface arthropods than T4 and T2 treatments.Analyses of surface arthropod trophic functional groups revealed that the artificial planted grass strips significantly increased the number of surface arthropods in various trophic functional groups,especially detritivores and predators,with the T6 and T8 treatments having 2.9 and 3.9 times more detritivores than the wasteland treatment(CKH),5.3 and 6.9 times more detritivores than the farmland treatment CKN,respectively,while the T6 treatment had 60%and 90%more predators than the CKH and CKN treatments,respectively.Correlation analyses revealed that most of the biodiversity characteristics of surface vegetation were positively correlated with the abundance of surface arthropods and the number of groups.Among them,vegetation coverage,above-ground biomass and species were significantly and positively correlated with the number of groups of surface arthropods,while vegetation abundance was negatively correlated with the abundance of surface arthropods and vegetation coverage was not correlated with the abundance of surface arthropods.Overall,in north China,artificial grass belts significantly increased the abundance and diversity of surface arthropods,supporting more arthropods,especially detritivores and predators,which enhanced the nutrient cycling and biological pest control functions of agro-ecosystems.Among the treatments with four different artificial plant combinations,the marginal grass belts with the six plant species combination and eight plant species combination were more beneficial for the establishment of surface arthropod communities and the improvement of farmland ecosystem functions in north China.