资源环境科技发展态势分析平台

Intensively managed pine (Pinus spp.) forests (IMPFs) in the southern U.S. are often harvested by clearcutting in conjunction with green tree retention (i.e., retention of unharvested or less-intensively harvested trees and other vegetation), which is thought to promote structural diversity and to benefit wildlife. Management units in IMPFs thus primarily consist of regenerating pineclearcuts (RCCs) plus retained cover in streamside management zones (SMZs: vegetative buffers along perennial and intermittent streams) and/or stringers (forested buffers along ephemeral drains). To understand relationships between retained structures and avian communities, we documented and compared species diversity of breeding bird species and avian guilds in three-year-old RCCs and associated SMZs and stringers on 60 IMPF management units within the South Central Plains ecoregion of the southeastern U.S. We detected 5617 individuals of 60 species. Eight species were considered "common birds in steep decline," one of which was frequently detected (Prairie Warbler, Setophaga discolor). Three of our 15 most frequently detected species were identified by Partners in Flight as "warranting management attention" for "moderate or high regional declines," and 19 other species were listed as "warranting management attention" but were uncommonly detected. Forty-two of 44 species documented in RCCs were also observed accessing retention cover areas. SMZs and stringers comprised an average of 17.4% of management unit area, but 27% of species were detected solely in retention cover types. There was an 84% species overlap between SMZs and stringers. Stringers augmented SMZ contributions to site avian diversity by hosting forest specialist guilds. Diversity of early-successional specialists was similar between stringers and RCCs, suggesting stringers also enhanced RCC contributions to site bird diversity. Furthermore, we detected several species only within stringers. Green tree retention land cover contributed to stand scale avian diversity disproportionately to its area, and in particular, stringer cover appeared to enhance the value to avifaunal species diversity of RCC and SMZ patches.