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181.
呼伦贝尔沙地治理战略布局探讨 总被引:3,自引:0,他引:3
根据呼伦贝尔沙地自然地理条件和生态建设工程的实际状况,将呼伦贝尔沙地治理规划成3大措施区、5大治理类型区,在每个类型区提出了相应的治理重点和主攻方向,并结合工程治理、休牧禁牧、生态移民实现沙地的全面保护和治理,消除沙害,使沙区生态环境根本好转,实现沙区经济社会可持续发展。 相似文献
182.
以某农村防洪工程为例,根据流域规划、工程现状、地形条件等因素,按照防洪标准,确定堤线布置形式。提出堤型方案,通过技术经济比较,确定合理堤型,即采用梯形断面均质土堤。 相似文献
183.
从土地发生学与结构学的角度出发,通过对山地区域土地分异规律的研究,运用景观法的原理建立了土地类型划分体系,选取地形地貌、土壤与植被条件作为土地类型划分的主要分异因素,在此基础上,对云南省永胜县顺州乡土地进行了类型划分,并分析了土地类型的空间结构与数量结构,以期为土地利用与生态建设等提供参考依据。 相似文献
184.
为了满足多品种生产的需要,林海雅马哈摩托有限公司导入了雅马哈的PC-PYMAC生产管理系统。介绍了该系统的制造基础信息模块、计划模块、实绩管理模块和盘点模块;针对该系统在林海雅马哈摩托生产应用过程中产生的问题提出了相应的解决错施。 相似文献
185.
中医理论在园林景观中的应用类型探析 总被引:1,自引:0,他引:1
以中医学、生态学、景观美学和环境心理学为理论基础,研究了中医理论在园林景观中的应用类型及各应用类型之间的异同,总结了中医理论在园林景观中的应用方式,并分析了目前中医理论在园林景观中应用时存在的不足,以期为中医理论在园林景观中的应用提供理论依据。 相似文献
186.
为对比不同结构尼龙网不同风速下的防风效应,开展对均匀型(A)、上密下疏型(B)、上疏下密型(C)3种不同结构尼龙网在6 m·s~(-1)、9 m·s~(-1)、12 m·s~(-1)指示风速下的风洞模拟试验。通过对不同结构尼龙网各风速下加速率等值线图和防风效能的对比分析,结果表明:1 3种结构尼龙网风场存在相似性但差异明显。B型尼龙网风影区下部存在加速区,A、C型则不存在;C型风影区中心位置较低。2 A、C型尼龙网防风效应随风速增大而降低,B型则相反。3测量范围内C型尼龙网防风效应明显优于A、B型。实际应用中应综合考虑沙障结构、风况等因素,尼龙网栅栏的布设建议选用上疏下密型结构。 相似文献
187.
Paula Cederberg Jan-Gunnar Gustafsson 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):19-32
Abstract The potential for extending organic wine production in Chile is discussed in relation to its history and present situation. The main objective is to present an overview of the production of organic wine in Chile, its certification, and national and international markets. During the wine harvesting season in March and April 2006, the authors visited and interviewed staff at four Chilean organic wineries. The wineries were all situated in the wine-producing centre of the country and were of variable sizes. One of the certification bodies in Chile was also interviewed. In addition to the field studies and interviews in Chile, various written information has been used. Second to Argentina, Chile is the country that produces most wine in Latin America. Vineyards cover a total of 110 000 hectares of the country's two million hectares of arable land. A study carried out in 2005 showed that 2000 hectares (almost 2%) of vineyards are organically cultivated. The organic production is operated by 32 different companies, which produce organic wine mainly for exportation to the international market. In Chile, the number of certified organic wine producers has increased in recent years in a trend directed by international demand and possible competitive advantages for Chilean wines. In order for a wine to be called ‘organic’ or ‘wine made from organically grown grapes’, the cultivation and final product must be approved by a certification company. In Chile there are three main active certification bodies; one national (Certificadora Chile Orgánico, CCO) and two international (the Swiss company IMO and the German company BCS). The study reveals a country with innovation and energy but facing strong pressures from the international market and its jungle of laws and directives, and the differing prestige of different certifications and labels. Chile as a wine-producing country has many competitors, and the production of organic wine could be a way to find diversity and exploit new market ground where environmental consideration concerns and sustainability are important targets. 相似文献
188.
《Scandinavian Journal of Forest Research》2012,27(3):272-280
Abstract Biomass has become a popular alternative to satisfy expanding energy demand and as a substitute for fossil fuels and phased-out nuclear energy in Europe. The European Union White Paper stipulates that the utilization of biomass shall increase to 1566 TWh by 2010. However it is often overlooked that the forest resources are already, to a large extent, used by the forest industries. When promoting biomass for energy generation the consequences for the forest industries also need to be considered. Sweden is an excellent case study, as there are vast quantities of forest resources, nuclear power is starting to be phased out, there are restrictions on expanding hydropower and the political desire exists to “set an example” with respect to carbon dioxide emissions. This paper attempts to estimate and analyse the supply of two types of forest resource, namely, roundwood and harvesting residues derived from final harvesting and commercial thinnings. Two separate supply curves are estimated: one for roundwood and one for harvesting residues. The cost structure is based on an economic-engineering approach where the separate cost components are constructed from the lowest cost element into aggregates for labour, capital, materials and overhead costs for each forest resource. The results indicate an unutilized economic supply of 12 TWh of harvesting residues in Sweden. However, after these 12 TWh have been recovered it becomes more profitable to use roundwood for energy purposes than to continue extracting further amounts of harvesting residues. 相似文献
189.
190.
Mapping soil organic carbon (SOC) and establishing any change over time are important because of CO2 fluxes between soil and atmosphere and cropland decreases in SOC. The latter is one of the main causes of soil fertility decline and increased erodibility. As most analytical methods underestimate total SOC content, correction factors are needed to avoid methodological bias when comparing SOC data from sampling campaigns using different analytical procedures. The traditional method for SOC analysis used to be, and in most cases still is wet oxidation in potassium dichromate, better known as the Walkley & Black method. In this study, we aim to estimate correction factors for the classic and modified version of the Walkley & Black method for different land use and soil type combinations for agricultural soils in north Belgium. General correction factors of 1.47 for the classic Walkley & Black method and 1.20 for the modified Walkley & Black method are proposed. The results show that sandy grassland soils are characterised by lower recoveries than silt loam grassland soils. Furthermore, the correction factor appears to increase with soil wetness. 相似文献