INRA, UMR 0980 BAGAP, BP 84215, 35042 Rennes, France; LTER - « Zone Atelier Armorique », Rennes, France.
INRA, UMR 0980 BAGAP, BP 84215, 35042 Rennes, France; LTER - « Zone Atelier Armorique », Rennes, France.
J Environ Manage. 2017 Dec 15;204(Pt 1):282-290. doi: 10.1016/j.jenvman.2017.08.054. Epub 2017 Sep 9.
Field margins are key features for the maintenance of biodiversity and associated ecosystem services in agricultural landscapes. Little is known about the effects of management practices of old semi-natural field margins, and their historical dimension regarding past management practices and landscape context is rarely considered. In this paper, the relative influence of recent and past management practices and landscape context (during the last five years) were assessed on the local biodiversity (species richness and composition) of carabid assemblages of field margins in agricultural landscapes of northwestern France. The results showed that recent patterns of carabid species richness and composition were best explained by management practices and landscape context measured four or five years ago. It suggests the existence of a time lag in the response of carabid assemblages to past environmental conditions of field margins. The relative contribution of past management practices and past landscape context varied depending on the spatial scale at which landscape context was taken into account. Carabid species richness was higher in grazed or sprayed field margins probably due to increased heterogeneity in habitat conditions. Field margins surrounded by grasslands and crops harbored species associated with open habitats whilst forest species dominated field margins surrounded by woodland. Landscape effect was higher at fine spatial scale, within 50 m around field margins. The present study highlights the importance of considering time-lagged responses of biodiversity when managing environment. It also suggests that old semi-natural field margins should not be considered as undisturbed habitats but more as management units being part of farming activities in agricultural landscapes, as for arable fields.
农田边缘是农业景观中维持生物多样性和相关生态系统服务的关键特征。人们对旧的半自然农田边缘的管理实践的影响知之甚少，而且很少考虑其过去管理实践和景观背景的历史维度。本文评估了最近和过去的管理实践和景观背景（过去五年）对法国西北部农业景观中农田边缘的鞘翅目昆虫群落的本地生物多样性（物种丰富度和组成）的相对影响。结果表明，最近的鞘翅目物种丰富度和组成模式最好通过四到五年前测量的管理实践和景观背景来解释。这表明鞘翅目昆虫群落对农田边缘过去环境条件的响应存在时间滞后。过去管理实践和过去景观背景的相对贡献取决于考虑景观背景的空间尺度。放牧或喷洒的农田边缘中鞘翅目物种的丰富度较高，可能是由于栖息地条件的异质性增加所致。被草地和作物环绕的农田边缘拥有与开阔栖息地相关的物种，而森林物种则占据了被林地环绕的农田边缘。在精细的空间尺度上，景观效应更高，在农田边缘周围 50 米范围内。本研究强调了在管理环境时考虑生物多样性的时滞响应的重要性。它还表明，旧的半自然农田边缘不应被视为未受干扰的栖息地，而应更多地被视为管理单元，作为农业景观中农业活动的一部分，就像耕地一样。
