Barré Kévin, Le Viol Isabelle, Julliard Romain, Chiron François, Kerbiriou Christian
Centre d'Ecologie et des Sciences de la Conservation Muséum national d'Histoire naturelle, UMR 7204 MNHN-CNRS-UPMC Paris France.
Agrosolutions Paris France.
Ecol Evol. 2017 Dec 30;8(3):1496-1506. doi: 10.1002/ece3.3688. eCollection 2018 Feb.
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 ( and ) of three species and for one ( 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 ( spp.). We did not detect any differences between OT and CT systems, and CT showed higher activity than CTH system for only one species (). Activity in OT of 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，农药使用的增加和耕作强度的加大对生物多样性有负面影响。这些农业实践的变化，如减少除草剂使用和耕作强度，对不同分类群有不同影响，尤其是在包括食虫蝙蝠在内的营养网络顶端。很少有研究比较农业实践对这类分类群的影响，总体而言，只是将传统农业与有机农业进行比较，而没有准确考虑其潜在实践，特别是在传统农业中存在多种选择的情况下。先前这些研究中出现的不同结果可能是由于对传统和有机系统中一些未考虑到的实践缺乏明确说明。我们在一个集约化农业景观中，对一块有机农田和三块传统农田相邻的麦田，进行了整夜的蝙蝠活动同步比较。所研究的有机农田（OT）采用不使用化学投入物的耕作方式（即土壤翻耕）。在研究的传统农田中，差异如下：使用少量除草剂的耕作方式（T）、使用少量除草剂的保护性耕作方式（即不进行土壤翻耕，CT）以及使用更多除草剂的保护性耕作方式（CTH），以控制杂草。我们使用了64个记录点（OT = 12；T = 21；CT = 13；CTH = 18），每晚在每个系统的农田内设置多个采样点。我们发现，对于三个物种中的两个物种（和）以及两个属中的一个属（ spp.），OT中的蝙蝠活动总是高于T系统中的活动，物种丰富度也更高。CT与T系统比较也得到了相同结果。CTH系统仅对一个属（ spp.）的活动高于T系统。我们未检测到OT和CT系统之间存在任何差异，CT仅对一个物种（）的活动高于CTH系统。 spp. 在OT中的活动总体分别比CTH和T系统高3.6倍和9.3倍，在CT中比T系统高6.9倍。我们的研究结果突出了有机农业的一个重要益处以及传统农业中的对比效应。在有机农业和一种传统系统之间未检测到差异是一个主要结果。这表明，即使目前有机农业难以实施，需要农民改变经济环境，但在保持产量并接近有机方法的生态效益的同时，传统农业仍可实现可观且容易的改进。
