摘要：We attempted a complete review of the empirical literature on effects of roads and trafficon animal abundance and distribution. We found 79 studies, with results for 131 species and 30 speciesgroups. Overall, the number of documented negative effects of roads on animal abundance outnumberedthe number of positive effects by a factor of 5; 114 responses were negative, 22 were positive, and 56showed no effect. Amphibians and reptiles tended to show negative effects. Birds showed mainly negativeor no effects, with a few positive effects for some small birds and for vultures. Small mammals generallyshowed either positive effects or no effect, mid-sized mammals showed either negative effects or no effect,and large mammals showed predominantly negative effects. We synthesized this information, along withinformation on species attributes, to develop a set of predictions of the conditions that lead to negative orpositive effects or no effect of roads on animal abundance. Four species types are predicted to respondnegatively to roads: (i) species that are attracted to roads and are unable to avoid individual cars; (ii) specieswith large movement ranges, low reproductive rates, and low natural densities; and (iii and iv) small animalswhose populations are not limited by road-affected predators and either (a) avoid habitat near roads due totraffic disturbance or (b) show no avoidance of roads or traffic disturbance and are unable to avoid oncomingcars. Two species types are predicted to respond positively to roads: (i) species that are attracted to roadsfor an important resource (e.g., food) and are able to avoid oncoming cars, and (ii) species that do not avoidtraffic disturbance but do avoid roads, and whose main predators show negative population-level responsesto roads. Other conditions lead to weak or non-existent effects of roads and traffic on animal abundance.We identify areas where further research is needed, but we also argue that the evidence for population-level effects of roads and traffic is already strong enough to merit routine consideration of mitigation ofthese effects in all road construction and maintenance projects
关键词：environmental impact; landscape connectivity; mortality; population density; road network;road density; road effect zone; road mitigation; species distribution; species richness; traffic density; traffic;volume
