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61.
10年以来,河北农业大学林学院在人才培养、科学研究、队伍建设、学术交流、社会服务等方面得到了长足的发展。除了学校的重视和政策支持,林学院将学科建设作为整个学院工作的核心,从学科方向整合到重点学科建设,采取了一系列措施。在河北农业大学建校110周年之际,回顾过去,总结经验,在学科专业建设、师资队伍建设、科研工作与服务能力建设、学术交流取得阶段性成就的基础上,积极谋划未来,切实树立特色铸校、人才强校、质量立校的理念,为建设特色鲜明的高水平区域性大学而努力奋斗。  相似文献   
62.
乔木  陈模 《干旱区研究》1995,12(2):54-57
根据新疆同一地貌区域形态成因,水热及农业发展方向和改造利用条件的相似性或不同地貌区间的差异性原则,建立起构造、新构造运动、外力作用,地貌形态等农业区划樗,以及农业地貌各级区域标志。  相似文献   
63.
伊犁河流域地表水资源优势及开发利用潜力研究   总被引:3,自引:0,他引:3  
伊犁河流域是新疆地表水系最发达、径流最发育、水资源最丰富的内陆河流域,具有流域降水丰沛,径流补给充分,径流量大;水系发达,河川密布;水量变化较小、泥沙含量较少、水质较好的资源优势。但受经济发展水平及产业结构层次的限制,伊犁河流域水资源总体上仍处于利用效率低下、生产经营方式落后、综合利用潜力巨大的初级开发阶段。依据部颁SL201-9《江河流域规划编制规范》和流域整体规划目标,经过水资源多目标开发平衡分析与评价,给出了伊犁河流域水资源综合开发和合理配置远景规划方案。  相似文献   
64.
Introduction   总被引:1,自引:0,他引:1  
Pedroli  Bas  Harms  Bert 《Landscape Ecology》2002,17(1):1-12
The realization of strategies for sustainable land use assumes specificresearch concepts from the local to the global scale (micro-, meso- andmacroscale). Therefore, landscape ecological science has to provideinvestigation methods for all these different scales. By combiningtop-down and bottom-up approaches in addition tocoupled GIS-model applications and traditional methods, the investigation oflandscape ecological structures and processes seems to be possible. Thepresented studies show this approach on examples of two study areas in EasternGermany: A watershed of 400 km2 and an administrativedistrict of about 4000 km2. The scale-specificapplicability of several models and methods were tested for theseinvestigations, and the validation of the calculated results are presented. Animportant outcome of the project should be the prevention of conflicts betweenagriculture, water management and soil, and water and nature conservation;based onrecommendations for land use variants with decreased pollutant loading withinagricultural areas. The scale specific investigations can be considered as abase for establishing sustainable land use.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   
65.
Magnetic resonance (MR) images may be useful for radiation planning due to greater contrast resolution. One disadvantage of MR images for radiation planning is the inability to incorporate electron density information into the dose calculation algorithm. To assess the magnitude of this problem, we evaluated radiation dose distribution in canine brain by comparing computed tomography (CT)-based radiotherapy plans with and without electron density correction. Computerized radiotherapy plans were generated for 13 dogs with brain tumors using 6 MV photons. A tissue-contouring program was used to outline the gross tumor volume (GTV) and the planning target volume (PTV) for each patient. Two treatment plans were generated for each dog. First, the plan was optimized without heterogeneity correction. Then the heterogeneity correction was implemented without changing any other plan parameters. Isodose distributions and dose volume histograms (DVHs) were used to compare the two plans. The D95 (dose delivered to 95% of the volume) within the PTV was calculated for each treatment plan and differences in the D95s were compared. The mean D95s without and with heterogeneity correction were 49.1 +/- 0.7 and 48.9 +/- 1.0Gy, respectively. The absolute mean percent dose difference without and with heterogeneity correction was 1.0 - 0.9% (-1.3-3.2%) and was not considered to be clinically significant. We found no clinically significant difference between CT-based radiotherapy plans without and with heterogeneity correction for brain tumors in small animals, which supports the use of MR-based treatment planning for radiotherapy of small animal brain tumors.  相似文献   
66.
新世纪保护区面临的挑战及其有效对策   总被引:1,自引:0,他引:1  
道路、水库、建筑物、不断扩大的农田和土地退化正在使自然景观的完整性受到严重破坏。所保存的未经干扰或少受干扰的天然生态系统的面积日益缩小,犹如海洋中的孤岛。生物多样性受到严重的威胁。在自然保护区中,物种迁移和基因流动的可能性也在不断地降低。生物区域规划被认为是一种较好的选择,它力求把保护区和栽培地区视为一个有机整体,遵循保护和发展密切结合的方针,制定行动计划并予以实施。本文根据保护区的管理情况、工作条件和科研状况等,对保护区或区域的类型进行了划分,针对现实,提出了如何实施生物区域规划。  相似文献   
67.
Promoting and preserving biodiversity in the urban forest   总被引:1,自引:0,他引:1  
Efforts at mitigating global biodiversity loss have often focused on preserving large, intact natural habitats. However, preserving biodiversity should also be an important goal in the urban environment, especially in highly urbanized areas where little natural habitat remains. Increasingly, research at the city/county scale as well as at the landscape scale reveals that urban areas can contain relatively high levels of biodiversity. Important percentages of species found in the surrounding natural habitat, including endangered species, have been found in the urban forest.

This contribution concisely highlights some examples of urban biodiversity research from various areas of the world. Key issues involved in understanding the patterns and processes that affect urban biodiversity, such as the urban–rural gradient and biotic homogenization, are addressed. The potential for urban areas to harbor considerable amounts of biodiversity needs to be recognized by city planners and urban foresters so that management practices that preserve and promote that diversity can be pursued. Management options should focus on increasing biodiversity in all aspects of the urban forest, from street trees to urban parks and woodlots.  相似文献   

68.
Sustainable development requires, among other things, that development projects not result in the degradation of natural resources for outdoor recreation. There has been a rapid increase in knowledge regarding the importance of the external environment to our health and well-being. Stress is reduced significantly when people are exposed to health-promoting nature and landscape values. Many people are actively choosing to reduce their stress. Doctors today prescribe outdoor walks in peaceful environments for the same purpose. A high level of traffic noise increases stress. This paper discusses the application of silent values in an infrastructure development project, the extension of Sturup Airport, east of Malmö, Sweden and Copenhagen, Denmark. Through estimating the change in noise resulting from the development, it is possible to integrate mitigating and compensating measures in the planning process discussions. Such measures can be negotiated as conditions for authorization of the project. The airport is situated in an area rich in nature values for recreation. The airport expansion will mean both new noise impacting "silent" areas and increasing noise levels in already noise-affected areas. In this study, we have taken a positive stand on the silent areas, mostly agriculture land, where compensation measures could be taken, thus balancing the loss of silent nature values for recreation. Silent areas that will not be affected are suitable and feassible for compensation measures thus can be called compensation areas. In this way the development of new recreational areas, preferably designed as urban forests, are critical preconditions for the negotiations for the airport extension. The conclusion is that urban forest investments for health and well-being can be an important part of strategic decisions in spatial planning. As preconditions for a permit, the development and financing of new urban forests and green areas can be part of the total development plan. This is an issue of global interest, as many countries are in a process of rapid urbanization, and urban greening and urban forestry have an important role to play in the process of promoting quality of life and improving environmental quality.  相似文献   
69.
青岛梅园的建设及梅花品种的搜集与选育   总被引:3,自引:2,他引:1  
在简介青岛梅园这一北方“新星”后,着重报道了其在建园中完成的两项科研成果,即①梅园快速规划设计与施工;②梅花品种的搜集、整理与新品种选育  相似文献   
70.
研究目的:为科学编制镇级国土整治规划提供理论依据,为同类研究提供参考。研究方法:文献研究、理论研究、实证研究。研究结果:国土整治规划必须贯彻一体化管理思想;提出一体化管理国土整治规划思想的含义、特征及辩证关系。研究结论:一体化管理的国土整治规划思想是指导镇级国土整治行动及规划编制行之有效的思想。  相似文献   
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