在农业景观中,传粉昆虫的生存繁衍与半自然生境的面积大小有关.集约化生产方式使半自然生境比例逐渐减少,农田比例不断增加,随着景观简化梯度的变化(农田比例逐渐增大),传粉昆虫群落多样性将会发生怎样的变化？选择黄河中下游典型农区巩义市为研究区域,采用诱捕盘法(Pan traps)进行农田、林地的传粉昆虫取样,以21个样点作为景观简化梯度(农田比例范围5％-86％)的呈现,基于每个样点的传粉昆虫多度和丰富度变化来探究景观简化对传粉昆虫多样性的影响.结果显示:区内累计捕获传粉昆虫39660头,优势类群包括双翅目(Diptera)、膜翅目(Hymenoptera)、鞘翅目(Coleoptera)等.采用逐步回归分析及线性拟合后发现景观简化程度与传粉昆虫多度和丰富度呈显著负相关(P＜0.05);景观简化对传粉昆虫类群间的影响也是有差异的,其中对鞘翅目多度的影响最为密切(R2 =0.27),同时对膜翅目和双翅目也有较大影响(R2 =0.14、R2 =0.11),景观简化与鳞翅目多度呈正相关;随景观简化的程度加深,农田生境中膜翅目多度呈显著下降趋势(P＜0.05),而林地中膜翅目多度变化不明显.在未来的景观规划中,应着重考虑传粉昆虫中鞘翅目类群的栖息地变化及食物资源状况.依据研究结果建议林地生境中应注重保护现有的自然植被群落,在人工林中可以种植一定面积的蜜粉源植物;农田生境内对杂草群落、半自然生境斑块进行合理规划的基础上,还可以种植线性景观植物作为传粉昆虫的食物源.%In agricultural landscapes,the survival and reproduction of pollinators depends on the size of semi-natural habitats.The intensive agricultural production model has caused a decrease in semi-natural habitats and an increase in the proportion of land dedicated to agriculture.This study aimed to quantify any changes in the diversity of pollinators following this increase in the proportion of land dedicated to agriculture.Our study area was in Gongyi City,which is a typical agricultural region located near the lower reaches of the Yellow River.Twenty-one study sites were collected from the northeast to the central area.Pan traps were used to capture pollinators from farmland and woodland habitats.Using the Akaike Information Criterion (AIC),we calculated the optional characteristics scales of the pollinators and landscape features by 500m,where landscape simplifying was determined in terms of farmland proportion.Finally,the proportion of farmland was chosen as the basis of landscape simplification,which provided us with 21 sample points as the simplified gradient of the landscape (the ratio of farmland should be between 5％ and 86％).We then explored the impact of landscape simplification on pollinator diversity,which was based on the species abundance and richness of pollinators at each sample point.We caught a total of 39660 individual pollinators.The most common orders caught included Diptera (26236 individuals),Hymenoptera (13893 individuals),and Coleoptera (2033 individuals).Stepwise analysis and linear fitting showed that landscape simplification directly influenced the richness and abundance of pollinators,with greater proportions of farmland significantly negatively correlating with the richness and abundance of species caught (P＜0.05).The effect of landscape simplification on different pollinator groups was variable.The effect of landscape simplification was most significant on Coleoptera (R2 =0.27),followed by Hymenoptera (R2 =0.14),and Diptera (R2 =0.11).Landscape simplification was correlated with an increase in the number of Lepidoptera individuals caught (R2=0.09).Hymenoptera abundance was significantly decreased in farmland habitats,while there was no observable change in Hymenopteran abundance in woodlands.Overall,as the proportion of farmland increased,we observed significant changes in the abundance and richness of species caught.Our results showed that the proportion of farmland directly affected the abundance and richness of pollinators caught.In certain areas the balance between farmlands and semi-natural habitats is inappropriate and needs to be carefully reconsidered by decision makers and stakeholders.During land use planning,there should be an emphasis on the habitat and food resources needed by the Coleoptera taxa of pollinating insects in particular.Our results also suggested that more attention needed to be paid to the protection of existing natural vegetation communities in woodland habitats,while nectar-producing plants could be planted in artificial forests.Moreover,linear landscape plants could be planted as a food source for pollinators alongside farmlands.To protect natural habitats,such as weed communities,linear artificial landscapes of a suitable size could be planted on the boundary of farmlands,which would have a significant ecological impact and help to protect resource insects,such as Hymenopterans.
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