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101.
Urban allotment gardens (AG) in Portugal have increased in recent years, as in many other European countries and worldwide. The contribution of these gardens to the happiness and well-being of urban populations has been recognized, but evaluations of their benefits are still very scarce. The objective of this study was to evaluate this contribution, based on the urban organic AG of the Devesa Park in Vila Nova de Famalicão, Portugal. The sample included 65 gardeners who completed the self-administered questionnaires of Bem-Estar Pessoal (personal well-being scale), Felicidade Subjetiva (subjective happiness scale) and sociodemographic characteristics. Respondents were mainly adults under 65 years, married and academically well qualified and about half of them had a professional activity, with nearly one third being retired. They considered themselves happy with their life (Personal Well-being Index = 74.5%) and revealed an optimistic and positive attitude towards life, regardless of economic or social difficulties. The increased frequency of visits for gardening was positively related to a greater perception of subjective happiness. The gardeners who visited the AG more frequently considered themselves happier from a self-perspective and in comparison with peers. It can be suggested that urban organic AG represent a means for enhancing citizen well-being, contributing positively to their feelings of happiness and life satisfaction, changing behaviours and developing personal capacities. Beyond economic measures, urban AG can be recommended to capture the well-being of societies.  相似文献   
102.
Empirical evidence from many regions suggests that most species would be least negatively affected if human food demand were met through high-yield agricultural production and conservation of nonfarm ecosystems (land sparing), rather than through wildlife-friendly farming over a larger area (land sharing). However, repeated glaciation and a long history of agriculture may lead to different results in regions such as western Europe. We compared the consequences of land sparing and land sharing on breeding bird species in 2 lowland regions of England, The Fens, with 101 species, and Salisbury Plain, with 83. We derived density–yield responses for each species and then estimated regional population size under regional food production strategies, including land sharing and land sparing, a range of intermediate strategies, and a novel mixed strategy. In both regions, more species achieved maximum regional population size under land sparing than land sharing. In The Fens, the majority of birds were loser species (estimated to have smaller populations under all food production strategies than in the preagricultural baseline scenario), whereas in Salisbury Plain the majority were winners (smaller populations in the preagricultural baseline scenario). Loser species overwhelmingly achieved maximum regional population size under land sparing, whereas winner species achieved maximum regional population size under either land sharing or an intermediate strategy, highlighting the importance of defining which groups of species are the target of conservation. A novel 3-compartment strategy (combining high-yield farming, natural habitat, and low-yield farming) often performed better than either land sharing or land sparing. Our results support intermediate or 3-compartment land-sparing strategies to maximize bird populations across lowland agricultural landscapes. To deliver conservation outcomes, any shift toward land sparing must, however, ensure yield increases are sustainable in the long term, do not entail increased negative effects on surrounding areas, and are linked to allocation of land for nature.  相似文献   
103.
近年来国际上提出将持续农业作为农业生产发展的战略目标,本文综述了国际上发展持续农业的形式及特点,论述广东省持续农业的现状和发展持续农业面临的挑战,最后针对广东省目前的实际情况,提出今后的发展方向和对策.  相似文献   
104.
应用生态学和系统论的原理,把可利用的生物物质通过沼气厌氧发酵形成良性生态循环系统。这样既解决了农村能源,保护了森林资源和植被,又解决了环境保护等问题。同时,把种植业和养殖业有机地结合起来,取得了综合效益。福州市郊泉头村生态工程建设从1986年起经过8年的试点,采用了沼气多级发酵工艺,成功地建造了沼气生态系统工程,促进了生产的发展,1993年产值达6800万元,人均产值93400元,成为福州市重点商品猪基地之一和菜篮子工程项目。  相似文献   
105.
世界替代农业及其发展趋势   总被引:3,自引:0,他引:3  
本文对世界替代农业的主要类型和特点、中国的生态农业与发达国家的替代衣业的区别以及世界替代农业存在的主要问题进行了较详细的阐述,最后对世界替代农业的发展趋势作了展望。  相似文献   
106.
Xyleborini are a species-rich tribe of ambrosia beetles, which are haplodiploid and typically mate among siblings within their natal brood chamber. Several characteristics of this tribe would predict the evolution of higher levels of sociality: high genetic relatedness within galleries due to inbreeding, high costs of dispersal and the potential benefit of cooperation in brood care within the natal gallery (e.g. by fungus gardening, gallery extension, offspring feeding and cleaning). However, information on the social system of these beetles is very limited. We examined the potential for cooperative breeding in Xyleborinus saxeseni by monitoring dispersal in relation to brood size and composition. Results show that adult female offspring delay dispersal despite dispersal opportunities, and apparently some females never disperse. The females’ decision to stay seems to depend on the presence of eggs and dependent siblings. We found no indication that female offspring reproduce in their natal gallery, as colonies with many mature daughters do not contain more eggs than those with few or no daughters. There is a significant positive relationship between the number of females present and the number of dependent siblings (but not eggs), which suggests that cooperative brood care of female offspring raises colony productivity by improving survival rates of immatures. Our results suggest that cooperative breeding is likely to occur in X. saxeseni and possibly other xyleborine species. We argue that a closer look at sociality within this tribe may yield important information on the factors determining the evolution of cooperative breeding and advanced social organization.  相似文献   
107.
西南地区干旱规律与节水农业发展问题   总被引:11,自引:1,他引:11  
除西藏以外的中国西南地区人口、耕地和农林牧渔总产值分别占全国的19.2%、19.1%和14.9%,是我国十分重要且潜力巨大的农产品生产基地。干旱是制约本区农业发展的重要因素。文章分析了西南地区的干旱特征,揭示出该区季节性干旱严重、区域性干旱突出、干旱类型多、连旱频率大的干旱规律,提出对农业生产危害最严重的干旱类型是春旱、夏旱和伏旱。从自然和经济开发的角度,分析了该区干旱的主要成因是降雨分布不均、水资源可利用率低、水土流失严重和水利工程滞后。在此基础上,提出了提高降雨利用率、提高水资源开发程度及大力发展生物节水技术的对策,特别是农业结构调整、抗旱作物选用、节水农耕农艺技术和发展经济植物篱(埂)等生物节水技术。  相似文献   
108.
科学施肥与农业生产可持续发展   总被引:4,自引:0,他引:4  
何小霞  曾思坚 《生态环境》2005,14(3):443-444
化肥的施用,实现了农业的增产,一百多年来为解决中国人民的温饱问题做出了重大贡献。肥料仍然是粮食安全的重要保障。但不合理施用化肥造成环境污染和食品安全问题,使人们产生了对化肥的错误认识。文章认为必须树立起科学施肥的观念,努力提高化肥利用率,形成有机、无机肥料合理配合使用的格局,促进农业生产可持续发展。此外,还认为应加强肥料市场管理,使之有法可依,并能迎接入世的挑战。  相似文献   
109.
110.
杜森  高祥照 《生态环境》2002,11(2):189-193
综述了目前国外精准农业的主要技术理论,着重围绕其在农田施肥管理中的应用,讨论基于GPS、GIS应用的农田施肥管理系统的开发和应用,提出精准农业技术理论在我国农田施肥管理中的应用设想。  相似文献   
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