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21.
广东省“十三五”环境保护战略思考   总被引:3,自引:0,他引:3  
"十二五"时期,在经济社会稳定发展的背景下,广东省环境保护取得了积极成效,但也存在结构性和格局性污染突出、污染呈现空间扩散态势等问题。在经济新常态背景下,为全面推进广东省"十三五"环境保护工作,在对当前环境问题分析及对未来环境形势研判的基础上,统筹谋划了广东省"十三五"环境保护目标指标及对策建议,以期对广东省率先基本实现现代化和全面建成小康社会起到推动作用。  相似文献   
22.
就"五水共治"规划中所涉及的复杂性问题,围绕"五水"间的协同性关系,明确县级"五水共治"规划的地位与作用,深化"五水共治"中的联动关系,从控制总量减少流域污染、改善生态降低洪水灾害、优化绿地功能减轻内涝、提高植被覆盖率保障山区型饮用水安全、动员社会节约水资源等主要途径,阐述了循环经济、滞洪湿地公共空间带、城市下凹式绿地等一系列相关技术手段,为编制县域"五水共治"总体规划提供基本思路、技术指导和支持。  相似文献   
23.
Honey bees, Apis mellifera L., bred for hygienic behavior uncap and remove diseased and mite-infested brood. We hypothesized that within a colony bred for hygienic behavior, there would be differences in olfactory sensitivity among bees of the same age. We predicted that bees that initiate the behavior by perforating and uncapping brood would have greater olfactory sensitivity to the odor of the diseased brood, and would be better able to discriminate between odors of healthy and diseased brood, compared to bees that complete the behavior by removing the uncapped brood from the cells. Electroantennogram recordings of 15- to 21-day-old bees from three colonies demonstrated that bees collected while uncapping dead brood had significantly greater olfactory sensitivity to all concentrations of diseased brood odor compared to bees collected while removing brood. Proboscis-extension reflex discrimination conditioning demonstrated that 15- to 21-day-old bees collected while uncapping discriminated significantly better and generalized significantly less between the odors of diseased and healthy brood compared to bees collected while removing, when the odor of diseased brood was rewarded, but not when the odor of healthy brood was rewarded. Bees collected while uncapping brood that had been pierced with a pin had significantly less olfactory sensitivity than bees collected while uncapping freeze-killed brood, most likely because the pierced brood had greater stimulus intensity. Initiation of hygienic behavior depends on the olfactory sensitivity of the bee and stimulus intensity of the abnormal brood. Differential olfactory sensitivity and responsiveness among hygienic bees could lead to the apparent partitioning of the behavior into uncapping and removing components.Communicated by R.F.A. Moritz  相似文献   
24.
Global information sampling in the honey bee   总被引:1,自引:0,他引:1  
Central to the question of task allocation in social insects is how workers acquire information. Patrolling is a curious behavior in which bees meander over the face of the comb inspecting cells. Several authors have suggested it allows bees to collect global information, but this has never been formally evaluated. This study explores this hypothesis by answering three questions. First, do bees gather information in a consistent manner as they patrol? Second, do they move far enough to get a sense of task demand in distant areas of the nest? And third, is patrolling a commonly performed task? Focal animal observations were used to address the first two predictions, while a scan sampling study was used to address the third. The results were affirmative for each question. While patrolling, workers collected information by performing periodic clusters of cell inspections. Patrolling bees not only traveled far enough to frequently change work zone; they often visited every part of the nest. Finally, the majority of the bees in the middle-age caste were shown to move throughout the nest over the course of a few hours in a manner suggestive of patrolling. Global information collection is contrary to much current theory, which assumes that workers respond to local information only. This study thus highlights the nonmutually exclusive nature of various information collection regimes in social insects.  相似文献   
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