The importance of spatial and temporal scale for agri-environment scheme delivery

摘要: There is currently little evidence that wider countryside agri-environment scheme (AES) management has led to population-level benefits for farmland birds and it timely consider why this might be the case, so AES options can improved if necessary. Two reasons particular not deliver landscape-scale population are they do take account of full temporal scale a resource gap provide resources at an appropriate spatial target population. This paper reviews published on both issues, focusing results field experiments used winter seed provision as model option. strong most existing measures aim over-winter food granivorous fail during late period, when need likely greatest. Consideration within-season changes, such vegetation growth height, could also increase value margins birds. Published research new data together suggest separation c. 1 km between patches would all individuals in local Chaffinch Fringilla coelebs Yellowhammer Emberiza citrinella populations with access resource. tallies well recommendation Environmental Stewardship England crop should sown no larger than 2 ha, more 3 ha/km . Spatial issues critical success terms degree which complementary resources, within or seasons, sufficiently close one another same need. Although based sound evidence, modern AESs still by revision their organization prescriptions. Revisions into will necessary bird recovery goals met. Such revisions include crops mixes managed specifically coordination agreements neighbouring farms ensure sufficient provided scale.