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1.
国外林区道路发展现状及启示   总被引:2,自引:2,他引:0       下载免费PDF全文
林区道路是林业和区域发展不可或缺的基础设施.德国、奥地利等较早实现工业化的欧洲国家林道建设起步早,现已形成了与本国林业生产作业体系相适应的完善的林道路网体系.奥地利林道密度已达到89 m/hm2,德国超过100m/hm2,英国、法国、美国、加拿大、澳大利亚和新西兰等国家也具备了密集的林道路网体系,而日本、印度、韩国和俄罗斯林道配置水平较低.文中概述了这些国家林区道路的发展现状和经验教训;针对我国林区道路总量不足、等级低下等严重滞后问题,提出合理提高林区道路密度和等级,林道建设要科学规划合理配置、重视森林生态保护,制定林道建设技术标准和规程,减少对环境的负面影响等建议.  相似文献
2.
东北林区伐区林道合理配置的研究   总被引:2,自引:0,他引:2  
卢成龙  郑登旋 《林业科学》1993,29(4):326-330
运用木材采运成本最低的理论,结合东北林区资源、自然条件,科学的确定林道间距和配置形式、达到适宜的集材距离,健全和完善了伐区林道规划体系,提高了路网理论的应用价值。  相似文献
3.
英国林区道路发展及启示   总被引:1,自引:1,他引:0       下载免费PDF全文
研究国外林区道路发展有利于借鉴相关成功经验。文中简介了英国林业发展概况,从林道功能演变及外部连通性、林区道路等级与林道网密度、林道网优化配置的影响因素和林道建设依据及关键技术指标方面概括了英国林区道路发展现状,从投资主体与审批、资金主要来源、林道投资管理以及私有林与国有林等方面分析了林道建设的投资及融资机制,从工程建设、项目质量、资金使用和环境评估方面总结了英国林道管理模式,从私有林主和政府共同投资林道建设、严格制定林区道路建设标准、以环境影响评估指导林道建设和促进林区道路的多功能利用等方面探讨了英国林道发展的4点主要启示,对于我国林区道路建设具有一定参考作用。  相似文献
4.
森林道路对山雀类利用人工鸟巢的影响   总被引:1,自引:0,他引:1  
于2002 年11月至2003年6 月间, 在韩国安养首尔大学冠岳植物园(37°25'05"N,126°56' 85"E)阔叶林、针叶林和针阔混交林内研究了森林道路对山雀类利用人工鸟巢的影响。对在人工巢箱中繁殖的山雀类,杂色山雀(Parus varius)、沼泽山雀( P. palustris)和大山雀(P. major)的繁殖对的数量、巢位、窝大小、卵重及卵大小进行了调查。调查结果显示,在 3 个研究区,杂色山雀在森林内部(距离道路 75–150m)的繁殖对数量,比森林边缘(距离道路 0–75 m)多,其窝大小、卵重等尺寸也明显比森林边缘高,但沼泽山雀基本不受森林道路的影响。在人类活动频繁的地区人工巢箱为洞穴鸟类提供良好的繁殖条件。人工鸟巢的设置将有利于这些鸟类的保护和管理。表 3 参 16。  相似文献
5.
In this study we developed a forest road design program based on a high-resolution digital elevation model (DEM) from a light detection and ranging (LIDAR) system. After a designer has located the intersection points on a horizontal plane, the model first generates the horizontal alignment and the ground profile. The model precisely generates cross-sections and accurately calculates earthwork volumes using a high-resolution DEM. The model then optimizes the vertical alignment based on construction and maintenance costs using a heuristic technique known as tabu search. As the distance between cross-sections affects the accuracy of earthwork volume calculations, the results were examined by comparing them with the exact earthwork volume calculated by the probabilistic Monte Carlo simulation method. The earthwork volumes calculated by the Pappus-based method were similar to those calculated by the Monte Carlo simulation when the distance between cross-sections was within 10m. The model was applied to a high-resolution DEM from the LIDAR of Capitol Forest in Washington State, USA. The model generated a horizontal alignment, length 827m, composed of five horizontal curves. We examined the number of grade change points. The results indicated that tabu search found the best solution ($61.42/m) with five grade change points. This was composed of two vertical curves that almost followed the ground profile. As the accuracy of a high-resolution DEM from LIDAR increases, the model would become a useful tool for a forest road designer because it eliminates or at least reduces the time-consuming process of road surveys.  相似文献
6.
基于GIS技术林区道路选线方案优化方法的研究   总被引:1,自引:1,他引:0  
根据林区道路修建的有关信息 ,建立了基于GIS技术的林区道路路线方案设计流程 ,在此基础上 ,应用层次分析法 ,建立林区道路路线方案优化的层次结构模型 ,对影响林区道路选线的多因素进行了综合分析 ,提出了基于GIS技术林区道路选线方案优化流程。该方法将对林区道路的修建提供一定参考价值  相似文献
7.
林道网密度研究中与经济有关的几个问题分析   总被引:1,自引:0,他引:1  
本文阐述了合理林道网密度的概念,它与实际布线的关系,以及推导公式过程中主要因子的选取。通过计算实例说明公式的适用条件,并对人员作业步行费问题进行了论述。  相似文献
8.
以竹林经营受益面积为指标,应用GIS空间分析、空间查询技术,研究竹林经营公路布线的合理性,以期为森林经营公路建设规划提供决策支持。  相似文献
9.
指出了超低等林区公路开设是速丰林基地建设的一项重要工作。通过对地形图相关知识的应用,提出了超低等林区公路开挖土方有效量化的方法,为工程发包单价设定提供基础数据。  相似文献
10.
A well developed network of roads must exist as a necessary infrastructure system in modern forestry to facilitate forest operations. But forest roads have the potential to disrupt the drainage characteristics of watersheds and lead to negative impacts on the environment with increased erosion and sediment yields. Numerous factors affect surface erosion of roads and sediment production potential; determining and ranking them could be a guide for management decisions to erosion control. In this study, the CULSED model (as an extension of ArcGIS) was used to estimate sediment delivery and the distribution of a road network, given the existing culverts. Using the model, some culverts were added to the road network around places with high sediment delivery in order to minimize it. After a correlation analysis and adjustment between sediment production and the factors, i.e., road width, road gradient, age of road and vegetation cover, the trend of changes in sediment delivery with model changes in the input was investigated with a sensitivity analysis of the model. The results show that adding new culverts to the road resulted in a significant reduction of sediment delivery. The most important factor affecting sediment delivery was road width, followed by road gradient, vegetation cover and age of road. Road width and gradient were positively correlated with sediment delivery, while vegetation cover and age of road were negatively correlated. The best model to show the relation between sediment delivery and road width as well as with road gradient was a linear model, for vegetation cover a cubic equation and for road age a power model. The results of sensitivity analysis showed that sediment delivery had the greatest sensitivity to changes of road width and was least sensitive to changes in the age of the road. This model can help to estimate sediment delivery with its spatial distribution, which can be used for optimization of cross drain systems and strategies of sediment control. Application of the model requires field trials to acquire the necessary input data. The reliability of our results is a function of the accuracy of inputs, especially digital elevation model.  相似文献
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