Data from: Tillage and herbicide reduction mitigate the gap between conventional and organic farming effects on foraging activity of insectivorous bats

The increased use of pesticides and tillage intensification is known to negatively affect biodiversity. Changes in these agricultural practices such as herbicide and tillage reduction have variable effects among taxa, especially at the top of the trophic network including insectivorous bats. Very few studies compared the effects of agricultural practices on such taxa, and overall, only as a comparison of conventional versus organic farming without accurately accounting for underlying practices, especially in conventional where many alternatives exist. Divergent results founded in these previous studies could be driven by this lack of clarification about some unconsidered practices inside both conventional and organic systems. We simultaneously compared, over whole nights, bat activity on contiguous wheat fields of one organic and three conventional farming systems located in an intensive agricultural landscape. The studied organic fields (OT) used tillage (i.e., inversion of soil) without chemical inputs. In studied conventional fields, differences consisted of the following: tillage using few herbicides (T), conservation tillage (i.e., no inversion of soil) using few herbicides (CT), and conservation tillage using more herbicide (CTH), to control weeds. Using 64 recording sites (OT = 12; T = 21; CT = 13; CTH = 18), we sampled several sites per system placed inside the fields each night. We showed that bat activity was always higher in OT than in T systems for two (Pipistrellus kuhlii and Pipistrellus pipistrellus) of three species and for one (Pipistrellus spp.) of two genera, as well as greater species richness. The same results were found for the CT versus T system comparison. CTH system showed higher activity than T for only one genus (Pipistrellus spp.). We did not detect any differences between OT and CT systems, and CT showed higher activity than CTH system for only one species (Pipistrellus kuhlii). Activity in OT of Pipistrellus spp. was overall 3.6 and 9.3 times higher than CTH and T systems, respectively, and 6.9 times higher in CT than T systems. Our results highlight an important benefit of organic farming and contrasted effects in conventional farming. That there were no differences detected between the organic and one conventional system is a major result. This demonstrates that even if organic farming is presently difficult to implement and requires a change of economic context for farmers, considerable and easy improvements in conventional farming are attainable, while maintaining yields and approaching the ecological benefits of organic methods.

众所周知，农药使用量增加与耕作强度提升会对生物多样性产生负面影响。此类农业实践的调整——如减少除草剂用量、简化耕作方式——对不同类群的影响存在差异，尤以营养网络（trophic network）顶层的食虫蝙蝠（insectivorous bats）类群最为显著。目前鲜有研究探讨农业实践对该类群的影响，且现有研究多仅比较常规农业（conventional farming）与有机农业（organic farming）的整体差异，未精准考量二者背后的具体耕作方式——尤其是存在多种替代方案的常规农业体系。既往研究中出现的相悖结果，可能正是由于未明确阐释常规与有机农业体系内未被纳入考量的具体耕作方式所致。本研究于夜间连续监测了集约化农业景观中1块有机农田与3类不同常规农业体系的相邻小麦田的蝙蝠活动情况。本研究中的有机农田（Organic Fields, OT）采用无化学投入的翻耕（即土壤翻转作业）方式。常规农田则分为三类：低除草剂使用的翻耕耕作（Tillage with low herbicide use, T）、低除草剂使用的保护性耕作（即无土壤翻转，Conservation Tillage with low herbicide, CT）以及高除草剂使用的保护性耕作（Conservation Tillage with high herbicide, CTH），三者均用于杂草防控。本研究共设置64个监测点位（OT组：12个；T组：21个；CT组：13个；CTH组：18个），每晚于各体系内的农田中选取多个点位开展采样监测。研究结果显示，在3个物种中的2个（库氏伏翼蝠Pipistrellus kuhlii、普通伏翼蝠Pipistrellus pipistrellus）以及2个属中的1个（伏翼蝠属Pipistrellus spp.）中，OT组的蝙蝠活动频次始终高于T组，且物种丰富度更高。CT组与T组的对比也得到了一致结果。仅在伏翼蝠属Pipistrellus spp.中，CTH组的蝙蝠活动频次高于T组。本研究未检测到OT组与CT组之间存在显著差异，且仅在库氏伏翼蝠Pipistrellus kuhlii中，CT组的蝙蝠活动频次高于CTH组。总体而言，OT组中伏翼蝠属Pipistrellus spp.的活动频次分别是CTH组与T组的3.6倍与9.3倍，CT组则是T组的6.9倍。本研究结果凸显了有机农业的重要生态效益，同时也揭示了不同常规农业体系间的差异化影响。本研究的一项核心结论为：有机农业体系与其中一种常规农业体系并无显著差异。这表明，尽管当前有机农业落地难度较高，且需要农户调整经济经营模式，但常规农业可通过简便易行的改进措施，在维持产量的同时逼近有机农业的生态效益。