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81.
彭璐  韦松林 《安徽农业科学》2007,35(27):8556-8557
在大力发展住区建设的同时,广州结合当地独特的地理气候特征和人文历史积淀,创造了一批高质量的安康住区。通过对新建居住小区环境建设的分析,指出当前居住小区环境建设中的问题,提出住区环境规划建设与生态结合的发展方向。  相似文献   
82.
The effects of short-term nutrient additions (NPKμ, 10 g·m- 2) and disturbances on the species diversity, functional traits, soil properties, and community assembly mechanisms of the herbaceous community in the Urat desert steppe were examined. A mixed linear model, principal component analysis, and null model methods were utilized and both disturbance and interaction treatments were found to significantly reduce species richness and β diversity. Short-term nutrient additions significantly reduced soil pH but increased soil electrical conductivity. Six functional traits of the dominant species (i.e. Stipa glareosa, Peganum harmala, Salsola collina, Corispermum mongolicum) and six community-weighted mean significant changes under the disturbance and nutrient addition treatments were identified. The disturbance and nutrient additions promoted the transformation of the dominant species in the community from conservative strategies to acquisitive strategies. The results of the two null models revealed that community assembly under the control tended to be a stochastic process, while the disturbance and interaction treatments tended to be deterministic processes, and that of the nutrient addition treatments tended to be weaker deterministic processes. Plant communities in the desert steppe responded and adapted to the nutrient additions and disturbances through changes in the dominant species and their crucial functional traits. © 2023 Chinese Academy of Sciences. All rights reserved.  相似文献   
83.
Ecotourism, by definition, aims to engage peoples’ interest in wildlife and the environment. The use of tourist roads and trails to access sites within protected areas (PAs) can detrimentally affect the behavior and distribution of species. The way mammals respond to anthropogenic pressures may differ across taxonomic, functional, and phylogenetic groups; nevertheless, how ecotourist trail-use affects these different diversity remains under-investigated. Here, we assessed 6 metrics of taxonomic, phylogenetic, and functional diversity for a mammal community in a PA in central China, recording how Trail use (using Trail type as a proxy) and habitat variables affected sightings and signs of mammals across 60 replicate 0.5 km transects. We then examined how Trail use affected the taxonomic, functional, and phylogenetic diversity indices of species (>1 kg). Using generalized liner mixed modeling, we identified that more used trail types had a greater adverse effect on all diversity richness indices than did less used trail types. Consequently, tourist pressure was associated with a general tendency to homogenize the site's mammal community. In contrast, the effects of Trail Types on all diversity evenness indices were non-significant. Furthermore, more developed and more heavily used trail types had a greater, significant negative effect on taxonomic, functional, and phylogenetic richness, whereas these richness indices were unaffected by minor trail types, used less intensively. As a general principle, lower biodiversity indices reduce ecosystem resilience, and so it is vital to better understand these responses to balance public access against biodiversity management in PAs.  相似文献   
84.
新农村视角下农民参与式小型水利   总被引:1,自引:0,他引:1  
用水户参与式灌溉管理是我国近年来在总结本国管理体制基础上结合国际管理经验提出的一项重大改革。新时期倡导“坚持以人为本,构建和谐社会”的社会主义“新农村”建设与发展过程中,国家高度重视农村基础设施的建设发展特别是农村水利设施,那么农村小型水利工程参与式管理体制目前状况如何、今后如何围绕“新农村”发展将是新时期农村水利管理体制发展所面临和需要解决的。  相似文献   
85.
科技推广作为农业综合开发土地治理项目的一项重要措施,应全面融入于项目区的整体建设之中。必须正确把握国家农业综合开发科技推广的特征与要求,实现思维定势上的创新;国家把解决“三农”问题放在各项战略任务的首位,强调坚持统筹城乡经济社会发展,扎实推进社会主义新农村建设。必须正确理解和准确把握社会主义新农村建设的内涵,实现科技推广工作中技术构建上的创新;同时要正确把握农村现实状况,实现运行机制上的创新。  相似文献   
86.
现代化的农机装备作为先进的劳动工具,推动了生产力和文明社会的快速发展。建设社会主义新农村,农业机械化既是充要条件,又是必要条件;农业机械化是实现生产发展、生活宽裕、村容整洁、环境和谐的手段、条件、保证。没有农业的机械化,不可能有真正意义上的社会主义新农村建设。  相似文献   
87.
石墨炉原子吸收光谱法测定新资源食品中的硒含量   总被引:1,自引:0,他引:1  
建立一种简便、快速、准确的食品中硒的测定方法;检测新资源食品芝麻叶、野生四叶参、野生菜葛根、野生葛花及桑蚕蛹中的硒含量。用1mg·mL-1硝酸镍为基体改进剂,加入体积分数为0.1%TritonX-100和0.5%硝酸(1∶1),以改善样液的表面张力。用HITACHIZ-5000型石墨炉原子吸收光谱仪及全自动进样方法进行硒含量测定。石墨炉采用光控升温方式,硒的灰化温度按程序升温方式进行,程序升温分为干燥、灰化、原子化和净化。该方法的测定限为18.6μg/L,精密度为3.26% ̄9.29%(RSD),加标回收率为92.1% ̄108.8%。该方法具有测定简便、快速和准确等特点,可作为食品中硒含量测定的良好方法。  相似文献   
88.
89.
Under the background of the new rural construction in China, it is an important scientific question and an urgent social task to construct the harmonious society and to achieve the sustainable regional development on how to construct concentrative residence and manage the human habitat environment in the fast industrializing and typically urbanizing area. This paper analyzed the problems in the construction of the human habitat envi- ronment in the rural area of southern Jiangsu, discussed the methodologies of planning and design for rural con- centrative residence, researched the human habitat environment improvement technologies, and put forward the resolution of the recycling community for the rural inhabitation, which aimed at demonstrating the practicing in rapidly urbanizing regions.  相似文献   
90.
The modernization has been the dream that Chinese nation has wished eagerly to realize all the time. In some sense, the modernization of China means urbanization. The reform and opening - up over the past 20 years , built and made the enormous achievement in urbanization of China, have changed the appearance of the city of China greatly. But to numerous traditional historical zones, what kind of urbanization way should on earth be taken, it has been the question long - term in dispute of the planning circles all the time. In this paper, Ciqikou community of Chongqing as an example, doing some discussions from sociology on this question, the author hopes, that for such difficult problem, by this settlement a piece of breach can be found as soon as possible.  相似文献   
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