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1.
JHERIME L. KELLERMANN MATTHEW D. JOHNSON AMY M. STERCHO STEVEN C. HACKETT 《Conservation biology》2008,22(5):1177-1185
Abstract: Coffee farms can support significant biodiversity, yet intensification of farming practices is degrading agricultural habitats and compromising ecosystem services such as biological pest control. The coffee berry borer (Hypothenemus hampei) is the world's primary coffee pest. Researchers have demonstrated that birds reduce insect abundance on coffee farms but have not documented avian control of the berry borer or quantified avian benefits to crop yield or farm income. We conducted a bird‐exclosure experiment on coffee farms in the Blue Mountains, Jamaica, to measure avian pest control of berry borers, identify potential predator species, associate predator abundance and borer reductions with vegetation complexity, and quantify resulting increases in coffee yield. Coffee plants excluded from foraging birds had significantly higher borer infestation, more borer broods, and greater berry damage than control plants. We identified 17 potential predator species (73% were wintering Neotropical migrants), and 3 primary species composed 67% of migrant detections. Average relative bird abundance and diversity and relative resident predator abundance increased with greater shade‐tree cover. Although migrant predators overall did not respond to vegetation complexity variables, the 3 primary species increased with proximity to noncoffee habitat patches. Lower infestation on control plants was correlated with higher total bird abundance, but not with predator abundance or vegetation complexity. Infestation of fruit was 1–14% lower on control plants, resulting in a greater quantity of saleable fruits that had a market value of US$44–$105/ha in 2005/2006. Landscape heterogeneity in this region may allow mobile predators to provide pest control broadly, despite localized farming intensities. These results provide the first evidence that birds control coffee berry borers and thus increase coffee yield and farm income, a potentially important conservation incentive for producers. 相似文献
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控制和降低城市上空SO2的环境浓度对于改善城市环境,促进城市生态的良性循环具有十分重要的意义。本文从上海市绿化三维量分布模型、与SO2浓度分布模型的相关分析入手,以季节变化作为对比因子,讨论了城市绿化植物群的数量及分布对城市上空SO2浓度分布的宏观影响;并据此提出了可有效地控制城市上空SO2浓度的绿地建设的基本原则。 相似文献
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综述了我国的餐饮泔水油及废油脂资源浪费、破坏环境现状,对比介绍了新工艺显著的经济及环保效益。 相似文献
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云南省蔬菜产区的生态环境问题与防治对策 总被引:2,自引:0,他引:2
概述了云南省蔬菜产区的基本情况和生态环境状况,提出了菜区污染的防治对策,认为菜区面临的化肥、农药污染等生态环境问题,可通过建立生态农业示范区和发展无公害蔬菜产业,以及结合环境综合整治予以解决。 相似文献
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应用开顶式熏气装置,以油菜和白菜为材料,分别将其暴露于模拟酸雨(pH2.8—5.6)和模拟酸雨与0.1ppmSO_2环境中,测定单独污染与复合污染对蔬菜生长反应和产量的影响。结果表明,酸雨(pH2.8)和酸雨(pH4.6)与0.1ppmSO_2复合处理均对LAR有明显抑制,LAR最多可减少37.5%。模拟酸雨(pH2.8,3.6)使蔬菜减产1.4—8.7%,而模拟酸雨与SO_2复合污染可使蔬菜产量减少7.9—28.9%(P<0.05)。 相似文献
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红外分光光度法测定石油类和动植物油 总被引:8,自引:0,他引:8
油是污染物达标排放总量控制项目之一,红外分光光度法较重量法、荧光分光光度法、紫外分光光度法测量油准确、可比,且标准油易制备。利用红外分光测油仪,严格控制空白值,做空白试验,能准确、快速的测定水中的石油类和动植物油。 相似文献
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<正> According to the leading national classification of the climate of China, given by B. Huang (revised version 1986), Hainan falls into the tropical climatic realm, subdivided into a "peripheral tropical" type for the northern part and a "middle tropical" type for the southern part of the island. While all-year-round frost-free conditions define the tropics in general, the 20t-isotherm for the coldest month represents the boundary between the peripheral tropical and middle tropical types. Compared to the tropical climate in general, Hainan experiences distinctly lower winter temperatures which thus result in a larger annual temperature variation. In terms of precipitation, Hainan records a long rainy season through the southwest monsoon and typhoon seasons from May until October while winter precipitation is comparably lower. Representing two agroclimatic hazards, strong typhoon winds and cold waves seriously affect Hainan. Although to be defined as "marginal tropica-1", the climatic conditions on Hainan 相似文献
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