外来植物物种的引进对路域生态的影响

公路绿化立足本地资源选择绿化植物受几个方面的限制:(1)公路绿化的面积非常大,本地物种的数量不足;(2)野生资源没有得到充分的驯化,野生习性强烈,发芽和成活率非常低;(3)早期生长速度慢,不能及时覆盖裸地控制水土流失;(4)遗传上的保守性和多样性.     

贵州省高等级公路绿化现状及其对策

文章以贵州省高等级公路绿化工程为研究对象,阐述了该省公路绿化现状及存在的主要问题,提出了改善高等级公路生态环境绿化状况的对策和建议,为贵州省的公路绿化设计提供参考。     

公路绿化植物的选择与搭配设计研究

文章从分析我国公路绿化现状入手,综合相关多学科的知识,阐述了公路绿化植物的选择原则、公路平、纵、横断面绿化植物选择要求以及植物搭配的原则。对于提高公路绿化的科学性和合理性具有指导意义。     

公路生态绿化的发展与应用

<正>随着经济的高速发展,国内公路绿化的水平也在不断提高,由以往的普通绿化逐渐向生态绿化转变。然而,当前国内的公路生态绿化整体水平低下,"生态绿化"只不过是名不副实的"躯壳"。要将真正的生态绿化理念科学地、合理地融入公路建设,有必要了解公路生态绿化的发展与应用,以及综合评价公路绿化水平的方法。     

公路绿化造林成活率的探讨

根据青海省生态环境恶劣、自然条件差的实际,就如何提高公路绿化造林成活率作一叙述.     

公路绿化效果快速检定技术

提出一种基于无人机航拍技术和计算机图像处理技术的公路绿化效果快速检定技术,由无人机整体调查(普查并识别未绿化或效果较差的部位)和局部样方抽查(布设样方,调查样方里的绿化覆盖度)两部分组成,两者在不同的尺度发挥作用,优势互补(点面配合、粗细结合),实现客观、准确、定量的公路绿化效果检定。     

北方干旱地区高速公路绿化美化的几个关键问题

公路绿化美化应纳入公路建设项目之中,绿化美化公路可提高公路的服务功能,提高绿化美化效果质量要从设计抓起,绿化美化工程要加强管理、科学施工,在公路建设过程中做好环境保护是人类文明进步的要求。     

宁夏自治区公路绿化技术政策探讨

文章从宁夏公路绿化建设的实际出发,考虑宁夏所处的自然环境条件,降雨量少,蒸发量大,而且不同地区分布不均;同时公路上不同构造物的特点和行车安全。将公路绿化政策与国家保护生态安全的方针结合起来,首先要体现法规的严肃性;其次要满足多方面的需要;第三是保护沿线的生态环境;第四,要保证行车安全。为此提出:(1)预防为主,将清洁生产观念灌输到公路绿化建设的各个环节;(2)因地制宜,不同区域采用不同的绿化指标;(3)不同的公路构造物,采用不同的绿化设计方案;(4)规范绿化工作的基本程序;(5)制定有针对性的中间和最终验收标准。     

高等级公路景观设计与建设

高等级公路绿化、景观设计是公路建设的系统工程,沿线人文景观、自然环境是人们注意的焦点,是高等级公路建设管理水平的综合体现,结合我省高等级公路绿化、景观建设取得的经验,介绍高寒、干旱、生态环境脆弱等特定环境下的公路绿化、景观设计指导思想、设计原则,不同路段的绿化方式.     

浅谈高速公路中央隔离带绿化美化技术措施——以丹拉公路河北省张家口高速公路边坡防护为例

中央隔离带是高速公路绿化中最具有生机和活力的部分,是高速公路最主要的有机组成部分之一。但高速公路中央隔离带绿化也受水分、降雨、风力、蒸发量、车流量等很多条件制约,具有一定的难度。本文结合丹拉国道主干线宣化至老爷庙(冀蒙界)公路绿化中央隔离带的绿化经验,提出了中央隔离带绿化的3个重点和难点及控制方法。     

攀爬植物在高速公路中分带绿化中的应用

文章以南友高速公路中分带绿化改造工程为依托,介绍了西番莲和炮仗花两种藤本植物的生态学特征,阐述了搭设网架种植攀爬植物的具体施工技术,并对比分析了搭设网架种植攀爬植物的新型绿化模式的效果及优势,为高速公路中分带绿化提供参考。     

新疆高速公路边坡绿化防护方法

针对现有的高速公路边坡现状,结合新疆境内高速公路边坡绿化防护措施,探讨了几种边坡绿化防护方法。     

公路绿化与环保的研究分析

为推动公路建设水平,确保公路正常运营和沿线生态环境可持续发展,文章总结了公路绿化的特点和功能,从安全性、经济性、生物多样性、景观性等方面分析了公路绿化设计的原则,并探讨了公路中央分隔带、路基边坡、互通立交、服务区的绿化设计内容,从公路环保的重要性,认知公路环保的内容、功能及意义,并多方角度的加以分析和采取措施,达到预期效果,把建设和环境紧密协调统一。并对公路环保的设计理念、评价指标、评价方法及施工阶段的环保措施进行了论述。     

“以树养路”举措在百色农村公路的实践

经费短缺一直是农村公路养护中的“瓶颈”难题,文章介绍百色农村公路通过建立以树养路的管养模式,利用公路边坡有效的坡面面积,种植速生桉等经济林木,破解农村公路养护经费短缺的难题,实现了“有路必养”的目标。     

Unbalanced development of inter-provincial high-grade highway in China: Decomposing the Gini coefficient

This study discusses the unbalanced development of Chinese inter-provincial high-grade highway from 1997 to 2013. It does so from the viewpoint of the inter-provincial Gini coefficient based on per capita mileage of high-grade highway, which is decomposed according to such dimensions as the increment of the Gini coefficient, the Gini coefficient of different types of high-grade highway, and the Gini coefficient between and within inland and coastal areas. The Gini coefficient of China’s per capita mileage of inter-provincial high-grade highway shows a declining trend year by year. According to the results from the decomposition of the contribution rate of different types of high-grade highway, the unbalanced development of inter-provincial high-grade highway is caused mainly by that of first- and second-grade highway. According to the results from the decomposition related to the increment of the Gini coefficient of China’s per capita mileage of inter-provincial high-grade highway, the decrease of the Gini coefficient from 1997 to 2013 was mainly the result of balanced distribution of high-grade highway among regions in China. According to the results from the decomposition of the Gini coefficient between and within inland and coastal areas, the unbalanced development of inter-provincial high-grade highway in China from 1997 to 2013 was caused mainly by the unbalanced development of inter-provincial high-grade highway in inland areas. Therefore, the authors argue that the government should pay more attention to protecting the environment and providing a suitable scale of highway network, which could promote long-term sustainable development.     

Has the transport-led economic growth effect reached a peak in China? A panel threshold regression approach

Using China’s province-level panel data from 1987 to 2010, this study explores the optimal level of transport infrastructure accumulation maximizing the growth rate. We investigate under what circumstances can additional transportation infrastructure capacity positively affect economic growth, based on panel threshold regression models. Our empirical findings suggest that there is a non-monotonic relationship between the stock of transport infrastructure and the long-run growth rate. The magnitude of transport-led economic growth effect significantly depends on the level of the existing transport network. The empirical results identify two endogenous cut-off points of efficiency of transport-led economic growth effect. When the highway network density is lower than 0.17 km/km², an insignificant positive relationship between highway infrastructure accumulation and economic growth was found. When the highway density is estimated between 0.17 and 0.38 km/km² or higher than 0.38 km/km², expanding the highway network has a significant positive effect on economic growth, but the magnitude of the impact is weaker in the latter, with the estimated coefficients equal to 0.23 and 0.09 respectively. Although China still enjoys a positive economic growth effect led by building more large-scale highway infrastructure, the magnitude of the effects of most provinces in China has already passed the saturation point and continuously expanding the highway network is not very productive.     

常春油麻藤在公路边坡绿化中的应用

文章结合常春油麻藤的生物生态学特性,介绍了常春油麻藤在公路边坡绿化中的应用技术,评述了其绿化效果,为公路边坡绿化防护提供经验借鉴。     

提高岩溶桩基地质钻探正判率的方法

文章总结岩溶地区公路桥梁桩基地质钻探存在的问题,阐述了提高岩溶桩基地质钻探正判率的方法,提出应重视勘察方法的应用和岩溶地区地质钻探的原则,对公路桥梁桩基的勘察具有参考意义。     

对公路工程中黄土湿陷性问题的探究

文章通过对公路工程中黄土湿陷性的试验探究,在结合我国公路工程发展特点的基础上,提出黄土增湿陷性量计算的主要方法以及黄土增湿速率的基本方法,除此之外,并分析了在路堤填土小于或者大于相对高度的时候,对黄土地基的湿陷变形不予以考虑。     

The strategic transportation research study — Its origins and purposes

The highway industry in the United States spends about $35 to $40 billion annually. Management of the industry is almost wholly decentralized. This decentralization plus diminishing fuel tax revenues used to finance road improvements have caused road research efforts to decline to a very low level. Comparisons between funds for highway research and those spent by private firms in similar industries show that private firms spend from 5 to 12 times the rate of highway agencies. The problem of how much to spend on research is difficult both for private-sector and for public-sector enterprises. The level of research spending is shown to correlate well with both profitability and growth in U.S. firms. Four methods used for making research decisions in the private sector are discussed. The goals of the Strategic Transportation Research Study (STRS), which is being conducted by the Transportation Research Board to examine highway and transportation needs, are described.