共查询到20条相似文献，搜索用时 31 毫秒
1.
Gary L. Latshaw 《Water, air, and soil pollution》1973,2(3):393-402
The ability of alternate highway designs, landscaping procedures, berms, and sound barriers to reduce the noise intrusion from highway traffic will be discussed. The effects of meteorology on the propagation of sound relative to these abatement techniques will also be presented. Traffic controls on speed and acceleration determine the noise emission levels from the traffic. The potential of these controls to reduce noise levels in the community is described. 相似文献
2.
Nicholas C. Yost 《Water, air, and soil pollution》1973,2(3):303-309
This paper deals primarily with state activity in the field of noise control. It covers motor vehicle noise, aircraft noise, noise and land use planning, and includes a discussion of what areas for future state legislation are left uncovered by federal preemption under the Noise Control Act of 1972. With regard to motor vehicle noise, California has been enforcing existing state laws that pertain both to sellers of new vehicles and to operators of all vehicles. The enactment of the Noise Control Act raises questions as to the continued legality of the existing new vehicle laws. California's aircraft noise regulations went into effect in December 1972. As a practical matter, full enforcement must await the satisfactory performance of the monitoring systems, none of which have been fully approved. The airlines have sued the state to invalidate the regulations. The outcome may well depend on the decision of the United States Supreme Court in Burbank v. Lockheed, that court's first aircraft noise regulation case, which was scheduled to be argued in February 1973. 相似文献
3.
基于区位势理论的农村居民点用地整治分区与模式 总被引：10，自引：8，他引：10
农村居民点整治是农村土地整治的重要抓手,也是新农村建设的必然选择.该文引入经济地理学的区位势理论,从区位角度对农村居民点开展定量研究,提出农村居民点区位势的概念,分析影响区位势的因素,构建农村居民点区位势模型,计算农村居民点的区位势和区位势能.以居民点区位势和区位势能为表征量,采用 GIS技术对农村居民点进行分区,并对居民点采用不同整治模式.以河北省曲周县为例,运用该技术方法对居民点用地进行整治,研究结果体现了影响农居点用地发展的各项因素和现势性,符合当地实际,在土地整治规划应用中取得良好的效果,验证了理论的可行和实用.该研究为实现农村居民点多元化和因地制宜的整治和发展模式,为农村居民点整治规划开辟了一条途径. 相似文献
4.
Riparian zones are important for the many ecosystem services they supply. In settled areas, the vegetation of such zones is shaped by human land-use; this often creates conditions under which alien plant species thrive. Alien plants have been shown to induce large-scale changes in riparian habitats, and they pose a major threat to the continued provision of key ecosystem services. We used direct gradient analysis to assess correlations between land-use and the composition of vegetation along a riparian river corridor in the highly transformed landscape surrounding Stellenbosch in South Africa’s Western Cape Province. Vegetation plots were sampled along the entire length of the river from headwaters to estuary (ca. 40 km). Plant community composition was analyzed in relation to land-use data collected in the field, and additional land-use variables computed from digital land-cover data. Patterns of plant community structure were found to be directly related to land-use, with measures of cover, richness, and diversity differing significantly among land-use types. Portions of the riparian zone adjacent to agricultural land had the greatest level of alien plant cover, while areas bordered by urban land maintained the highest alien species richness. Areas adjacent to grazing and natural lands showed intermediate and low levels of invasion, respectively. Several native species were found to persist in areas with high abundance and diversity of invasive alien plants, suggesting that they will be valuable focal species for future restoration attempts. Due to the level of human-mediated change in many areas of the riparian zone, restoration to historic conditions over most of the river is not considered feasible. These areas should be recognized as examples of novel ecosystems, and management efforts should focus on restoring or creating desirable ecosystem functions, rather than on achieving assemblages comprising only native species. 相似文献
5.
为了探索莱芜市土地利用变化规律,论文分别基于Markov模型与GM(1,1)模型对莱芜市进行了2015—2050年土地利用变化预测,分析讨论了预测结果。结果表明:(1)2种预测模型得出各地类变化趋势一致,短期内相应年份预测值吻合度高,说明短期内预测结果可信,中长期预测的趋势可作参考。(2)耕地在2015—2020年之间基本保持不变,2020—2050年呈小幅度减少趋势;而园地、林地、草地自始至终都为减少趋势,其中草地的减少幅度最大;城镇村及工矿用地、交通运输用地为增加趋势,其中城镇村及工矿用地增幅最大;水域及水利设施用地、其他土地略有减少,幅度很小。2种模型预测的短期内预测结果是可信的,可为莱芜市土地利用规划提供科学依据,预测方法可为土地利用变化预测提供参考。 相似文献
6.
The Ljubljana-Razdrto highway and the parallel Ljubljana-Trieste railway cut through critical brown bear (Ursus arctos) habitat in south-central Slovenia. These high speed, high volume traffic axes are located close to the main dispersal corridor for bears from the Dinaric Mountain range into the Alps. We analyzed radiotracking data of 15 individual bears that lived within 10 km of the highway, compared transportation related and overall known bear mortality, and analyzed the spatial distribution of bear-vehicle accidents. The highway posed a home range boundary to resident bears, but was not an absolute barrier. Transportation-related mortality was high in the vicinity of the highway and railway, and averaged 31% of the total known local mortality from 1992 to 1999. At present the detrimental impact of transportation routes on the bear population in Slovenia is modest due to the high density of bears and the low density of highways—but new highways are planned or already under construction. Managers have to be aware that, due to bears large home ranges and long dispersal distances, a single highway affects bears from a huge area—emphasizing the importance of international cooperation and a landscape approach in highway planning. 相似文献
7.
基于景观格局的农用地整理道路规划布局方法 总被引：3，自引：1，他引：2
探索基于景观格局理论的农用地整理道路规划布局方法,使农用地整理中道路规划布局与景观格局相结合。该文运用景观格局廊道特征指数建立农用地整理中道路规划布局标准,以arcGIS软件作为工具进行农用地整理道路规划布局。研究发现,运用景观格局廊道特征指数建立农用地整理中道路规划布局标准明确了改善项目区景观格局方面的目标,指导农用地整理从景观格局角度规划布局道路,可完善项目区景观功能及结构,提高项目区土地生态系统稳定性。 相似文献
8.
基于激光测距仪的温室机器人道路边缘检测与路径导航 总被引：1，自引：3，他引：1
针对温室内移动机器人的应用需求,该文提出了一种应用于温室内移动机器人自主行走的温室道路边缘检测与导航算法。此方法利用激光测距仪获取当前视场内路面、作物及障碍物信息,根据温室路面平整度高于作物冠层外表面的特点,检测道路边缘并生成移动机器人下一采样控制周期的期望航向,然后根据机器人几何与物理模型推算左右驱动轮速度调整指令,使移动机器人保持沿道路行走而不进入作物区中。该算法的有效性在温室移动机器人Walle平台上得到了验证,机器人偏离道路中心线的平均值为-1.2707 cm,均方误差为2.6772。 相似文献
9.
Dilek Turer 《Water, air, and soil pollution》2005,166(1-4):251-264
Soils along highway environments typically contain high concentrations of heavy metals because of non-point contamination sources, most commonly vehicle exhaust and wear of vehicle parts. Pb, Zn, Cu, Cr, Sb, Ba and Ra concentrations of soils along roadways with very low traffic volumes in a rural portion of San Patricio County, Texas, have been studied in order to distinguish the effects of a point source (an industrial waste landfill) from the effects of traffic. The highest concentrations of Zn, Cr, Sb, Ba and Ra were detected in soils along the access road to the landfill. The association of high Ba values with high Ra values suggests that the most probable sources of this contamination were oilfield waste from storage tank bottoms, which were disposed of in landfill waste pits and were also spread over roads within the landfill to decrease dust. Outside the landfill along a different roadway, a second contamination area which was characterized by very high Ba but low Sb and Ra concentrations compared to background values, has been detected. Drilling mud spill is the most probable source of this contamination. The contaminations caused by these two point sources differ from typical vehicle-sourced contamination in two ways: their areal extent was limited and contaminants were not typical for highway environments (like Ba and Ra). Like vehicular contamination, however, these areas were confined to the immediate vicinity of the roadways. Another difference is that Pb in most vehicle-contaminated areas is strongly bound to the soil constituents, mostly organic matter, whereas the point source Pb was found to be readily exchangeable and to have no association with organic matter. 相似文献
10.
我国土地利用规划环境影响评价研究进展及展望 总被引：2，自引：0，他引：2
我国土地利用环境问题日益突出,土地利用规划环境影响评价研究成为当前土地资源可持续利用研究的前沿课题.文章诠释了土地利用规划环境影响评价的概念;并且对当前土地利用规划环境影响评价研究的主要研究内容及研究进展进行了综述,提出了在系统分析土地利用规划环境影响机理的基础上,以环境友好型土地利用规划为导向的土地利用规划环境影响评价研究体系.其中基于土地利用规划层次性和空间性的环境影响评价指标体系的构建、评价方法的选择以及土地利用规划环境影响评价在土地利用规划中的应用研究仍是未来土地利用规划环境影响评价研究的主要研究方向. 相似文献
11.
基于土地评价的基本农田划定方法 总被引：30，自引：15，他引：15
为了在基本农田划定中实现数量与质量并重的目标,该文以辽宁省东港市为例,借助GIS技术,从耕地的自然条件和立地条件两方面考虑,选取耕地等别、坡度、道路通达度、水利设施状况以及与相邻土地利用类型的适宜性等因素作为评价指标,建立一种以土地评价为基础的“按质定量”的基本农田划定方法。研究结果表明：东港市评价分值≥90分的耕地较少,只占耕地总面积的23.73%,且无规律地散步在整个区域内;若使其基本农田保护率达到国家规定的指标,评价分值≥70分的耕地区域是理想的基本农田保护区。实证研究表明此种方法可以减少基本农田划定中人为因素的干扰,使得基本农田的划定更为科学合理。 相似文献
12.
车辆运动引起路面动力反应的研究 总被引：5，自引：0，他引：5
利用变分原理，研究分析了在车辆运动作用下，弹性Ｗ地基上的刚性路面的动力反应。讨论分析了路面位移的变化趋势并且对车辆的轮距、轴距、重量等参数对路面动力反应的影响进行了初步的探讨。该文的研究可为进一步的路面损伤研究提供理论依据 相似文献
13.
Michael L Gibeau Anthony P Clevenger Stephen HerreroJack Wierzchowski 《Biological conservation》2002,103(2):227-236
Few studies have reported the effects of multiple human activities on grizzly bears, Ursus arctos. We document the degree of grizzly bear response to various human developments as a function of multiple interacting variables based on observed median distances to roads, trails and development features in a landscape where human presence is widespread. Female grizzly bears remained further than males from paved roads regardless of habitat quality or time of day. Males were found closer to paved roads when within or adjacent to high quality habitat and during the period of least human activity. The combination of traffic volume and highway configuration, however, overrides a bear’s attraction to high quality habitats for high-speed, high-volume, highways. Avoidance of busy transportation corridors was strongest in the adult segment of the population. Bears were found closer to trails during the human inactive period when within high quality habitat and further from trails when distant to high quality habitat. Our data indicated an inverse relationship between the sexes in response to vehicles and traffic noise compared to the response to human settlement and encountering people. Female bears were found further away than males in relation to vehicles and traffic noise, yet found closer than males to human settlement and places where people may be encountered. Those males that were more willing to exploit high quality habitat near roads, did so at night and where hiding cover was present. Adult females were the most risk-averse cohort, choosing to avoid humans instead of seeking out high quality habitats. Adult female grizzly bears were influenced most by human activities and development. Management agencies must maintain access to high quality habitat, especially for adult females, and create new opportunities to support the reproductive potential of the population. 相似文献
14.
利用马尔柯夫过程预测蒙阴县土地利用/覆被格局变化 总被引：2，自引：0，他引：2
为了解蒙阴县土地利用/覆被的变化规律及其未来变化,由蒙阴县1997年和2007年2个时期的遥感图像获得的土地利用/覆被数据,确定土地利用/覆被的初始状态矩阵和转移概率矩阵,据此用马尔柯夫模型对研究区的土地利用/覆被格局的未来变化趋势进行了预测。结果表明:蒙阴县土地利用/覆被格局正处在一种变化状态,耕地、草地、水域及水利设施用地、未利用地面积在今后一段时期内仍呈减少趋势,到2017年耕地面积比例较2007年减少3.22%,林地、城镇村及工矿交通用地仍呈增加趋势,其中以林地增长幅度较大,到2017年其占比将达到43.45%。根据模拟结果可调整各类土地利用/覆被格局,为宏观决策提供科学依据。 相似文献
15.
How do butterflies define ecosystems? A comparison of ecological regionalization schemes 总被引：1，自引：0，他引：1
Ecological regionalizations, such as ecoregions or environmental clusters, are often used as coarse filters for conservation. To be effective biodiversity surrogates, regionalizations should contain distinct species assemblages. This condition is not frequently evaluated and regionalizations are rarely assessed comparatively. We used a national dataset of Canadian butterfly collections to evaluate four regionalizations (ecoregions, land cover and productivity regime classifications, and a spatial grid) at two thematic resolutions using analysis of similarity (ANOSIM) and species indicator values. Overall, the spatially constrained schemes (ecoregions and grids) best captured patterns of butterfly community composition and species affinities, indicating that butterfly communities are strongly structured by space at the continent scale. In contrast, when comparing regions only within spatial or environmental neighbourhoods (i.e., comparing between regions that are adjacent along geographic or environmental gradients), all regionalizations performed similarly. Adjacency in environmental space is thus as important as physical adjacency at determining community dissimilarity. Productivity regimes and land cover will be useful biodiversity surrogates when considered in conjunction with space or within a spatially constrained area. This finding was confirmed with two ecoregional case studies (of the Algonquin-Lake Nipissing and Thompson–Okanagan Plateau ecoregions), which also revealed that the relative performance of regionalizations depends upon the context of the study area. We conclude that including species data can improve the efficiency of environmental surrogates for systematic conservation planning. 相似文献
16.
基于用地竞争的矿业废弃地再利用用地类型判定 总被引：2，自引：1，他引：1
合理确定矿业废弃地再利用用地类型,对满足矿业资源经济转型用地需求、优化矿区土地利用结构具有重要意义。该文以泽州县长河流域为研究区域,从适宜性和驱动力2个层面构建了矿业废弃地再利用用地竞争力评价指标体系,进而构建了基于该指标体系的矿业废弃地再利用用地竞争评价模型,并基于研究区行政界线图及矿业废弃地分布图,以矿业废弃地图斑为评价单元,量化评价指标,评价矿业废弃地再利用用地竞争力。采用三角模型,根据用地竞争力组合,对矿业废弃地再利用用地类型进行理论判定。研究结果表明:研究区中占总量50%的矿业废弃地可再利用为建设用地,主要分布在经济基础较好的乡镇周边及省道两侧;40%的矿业废弃地可再利用为农用地,主要分布于村庄周围;10%的矿业废弃地可再利用为生态用地,主要位于山区及水域附近。该研究结果可为优化矿区土地利用结构及矿业废弃地整治规划提供决策依据。 相似文献
17.
This study focuses on farmers' perceptions of roadway safety and reviews specific and pertinent North Carolina rural road crash data to evaluate their perceptions and concerns. A survey was mailed to 1,357 prospective participants throughout North Carolina. Of these, 656 (48.3%) North Carolina farmers completed and returned the survey. The study revealed that while the majority of respondents took a number of specific safety measures to ensure their safety while driving their tractor on rural roads, most believed that driving their tractor on rural roads was more dangerous than it was five years ago. Few respondents believed that laws governing tractors on rural roads are well known by urban residents. While a majority of the respondents would support a law to mandate the use of a slow-moving vehicle (SMV) emblem on the back of slow-moving farm equipment, a majority also believed that a more effective way to mitigate potential crashes would be to ensure that all farm vehicles had blinking or flashing lights, that diamond-shaped caution signs depicting a tractor were posted on roadways with frequent tractor traffic, and that roadway shoulders were created or widened on roads with heavy farm traffic so that tractors could move off the roadway. Only 22% of respondents felt safe driving their tractor on rural roadways in North Carolina. Most respondents felt that the biggest problem with roadway safety was the lack of respect and increased speed of other drivers. Recent data indicate that in crashes involving farm vehicles, citations were issued to 34% of the non-farm vehicle operators and 24% to farm vehicle operators. For those driving non-farm vehicle who were deemed at fault, 66% were cited for failure to reduce speed. For those driving farm vehicles, the most frequent citation involved the lack of safe movement. 相似文献
18.
村域尺度的不同乡村发展类型多功能特征与振兴方略 总被引：4，自引：3，他引：1
村域是中国农村社会经济活动的基本单元,科学划分乡村发展类型是分区分类推进乡村振兴的基础和关键。该研究在考虑规划约束的前提下,从经济条件、交通区位、资源禀赋和生态环境质量4个维度构建密云区乡村综合发展评价指标体系,并借助SOFM网络模型和地理探测器工具系统划分乡村发展类型。结果表明:1)在经济发展、交通区位等综合影响下,密云区乡村发展的空间分异特征明显,其发展水平总体呈现"水库南部水库北部"的特点。其中,密云镇、穆家峪镇和十里堡镇内的乡村发展最为突出,其乡村发展均处于较高级别以上;古北口镇和新城子镇的乡村发展弱。2)将密云区乡村划分为经济交通主导高水平区、交通生态主导高水平区、资源生态主导中高水平区等7大类,其中交通生态主导高水平区和经济生态主导中高水平区是主要的乡村发展类型,集中分布在不老屯、大城子、巨各庄、穆家峪、西田各庄、冯家峪和溪翁庄等镇。交通生态主导高水平区村庄生态环境质量较高,交通区位优势明显,叠加上较强的经济实力,乡村综合发展水平高。经济生态主导中高水平区村庄具有较强的经济发展水平和生态环境质量,乡村综合发展水平也较高。3)基于多功能视角梳理各类型区的功能特征,遵循"重点发展优势功能、适度提升弱势功能"的思路提出村庄振兴建议,以期为制订差异化的乡村振兴策略提供依据。 相似文献
19.
We examined the spatial patterns and factors influencing small terrestrial vertebrate road-kill aggregations in the Bow River Valley, Alberta, Canada. We surveyed roads varying in traffic volume, configuration and adjacent landscape attributes for road-kills between 1997 and 2000. The spatial pattern of road-kills was described using neighbour K statistics. We investigated the importance of road-kills at three taxonomic levels using logistic regression. Mammal and bird road-kill indices were consistently higher on a low volume parkway than on the high-speed, high volume Trans-Canada highway (TCH). Birds were more vulnerable to collisions than mammals on the TCH. Road-kill aggregations were nonrandomly distributed. Parkway road-kills were aggregated on small scales and characterized by low clustering intensities compared to the TCH. Road-kills were less likely to occur on raised sections of road. Road-kills tended to occur close to vegetative cover and far from wildlife passages or culverts. Our findings reveal how two distinct road types can have different effects in terms of vertebrate mortality and their spatial pattern. We recommend a series of mitigation measures for existing roads or future road planning projects. 相似文献
20.
分析了乡镇土地利用总体规划编制存在的问题,探讨了乡镇土地利用总体规划编制的技术思路、技术要点,例举了应用实例,可供乡镇土地利用总体规划编制参考。 相似文献