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1.
An extensive road system with rapidly increasing traffic produces diverse ecological effects that cover a large land area. Our objective was to evaluate the effect of roads with different traffic volumes on surrounding avian distributions, and its importance relative to other variables. Grassland bird data (5 years) for 84 open patches in an outer suburban/rural landscape near Boston were analyzed relative to: distance from roads with 3000–8000 to >30,000 vehicles/day; open-habitat patch size; area of quality microhabitat within a patch; adjacent land use; and distance to other open patches. Grassland bird presence and regular breeding correlated significantly with both distance from road and habitat patch size. Distance to nearest other open patch, irrespective of size, was not significant. Similarly, except for one species, adjacent land use, in this case built area, was not significant. A light traffic volume of 3000–8000 vehicles/day (local collector street here) had no significant effect on grassland bird distribution. For moderate traffic of 8000–15,000 (through street), there was no effect on bird presence although regular breeding was reduced for 400 m from a road. For heavier traffic of 15,000–30,000 (two-lane highway), both bird presence and breeding were decreased for 700 m. For a heavy traffic volume of ≥30,000 vehicles/day (multilane highway), bird presence and breeding were reduced for 1200 m from a road. The results suggest that avian studies and long-term surveys near busy roads may be strongly affected by traffic volume or changes in volume. We conclude that road ecology, especially the effects extending outward >100 m from roads with traffic, is a sine qua non for effective land-use and transportation policy.  相似文献   

2.
An extensive road system with rapidly increasing traffic produces diverse ecological effects that cover a large land area. Our objective was to evaluate the effect of roads with different traffic volumes on surrounding avian distributions, and its importance relative to other variables. Grassland bird data (5 years) for 84 open patches in an outer suburban/rural landscape near Boston were analyzed relative to: distance from roads with 3000–8000 to >30,000 vehicles/day; open-habitat patch size; area of quality microhabitat within a patch; adjacent land use; and distance to other open patches. Grassland bird presence and regular breeding correlated significantly with both distance from road and habitat patch size. Distance to nearest other open patch, irrespective of size, was not significant. Similarly, except for one species, adjacent land use, in this case built area, was not significant. A light traffic volume of 3000–8000 vehicles/day (local collector street here) had no significant effect on grassland bird distribution. For moderate traffic of 8000–15,000 (through street), there was no effect on bird presence although regular breeding was reduced for 400 m from a road. For heavier traffic of 15,000–30,000 (two-lane highway), both bird presence and breeding were decreased for 700 m. For a heavy traffic volume of ≥30,000 vehicles/day (multilane highway), bird presence and breeding were reduced for 1200 m from a road. The results suggest that avian studies and long-term surveys near busy roads may be strongly affected by traffic volume or changes in volume. We conclude that road ecology, especially the effects extending outward >100 m from roads with traffic, is a sine qua non for effective land-use and transportation policy.  相似文献   

3.
Vehicular Contamination of Dust in Amman, Jordan   总被引:1,自引:0,他引:1  
Road dust from four traffic areas; the city center, tunnels, closed car parks and a residential area was collected from the urban part of Amman and analyzed for polycyclic aromatic hydrocarbons (PAH) and heavy metals content.Total PAH and selected heavy metals were in the range of a few gg–1. The distribution of PAH was controlled by the arid climatic conditions. PAH distribution in the street dust tended to be dominated by 4- and 6-ring PAHs with significantly less 2- and 3-ring PAH reflecting volatilization of the latter under the hot and dry climatic conditions. However, both PAH and heavy metal concentrations were affected by the densities and conditions of traffic activity at the various sites. Generally, the highest concentrations of both PAH and heavy metals were found in the tunnels and the lowest in the residential areas.Significant correlation between PAH and total organic matter (TOM), lead and cadmium indicated that PAH and heavy metals in street dust of heavily traffic areas are strongly affected by automobile exhaust emission and that those in the residential areas have another source, most probably street material erosion.  相似文献   

4.
Electric arc furnace dust (EAFD) is one of the by-products of steelmaking industry which has been classified as hazardous due to containing some heavy metals such as Zinc, Cobalt, Copper, Lead or Cadmium. This research aims at solving the problem of this hazardous waste by solidification/stabilization through mixing it with asphalt cement to be used for road construction. EAFD was used as an additive to the asphalt concrete mixtures with five percentages (0%, 5%, 10%, 15% and 20%) by volume of binder. Penetration, ductility, specific gravity, softening point, flash point, fire point and rotational viscosity were analyzed. It was found that while the penetration and ductility were decreasing with the increase of EAFD concentration in the binder, specific gravity, softening point, flash point, fire point and rotational viscosity were increasing. Finally it has been concluded that the results are promising for dual achievement (1) to solve an environmental problem and (2) to use the EAFD for road construction.  相似文献   

5.
We combined a natural experiment with field surveys and GIS to investigate the effects of dust from recreational trails and access roads on the federally threatened Valley elderberry longhorn beetle (“VELB,” Desmocerus californicus dimorphus) and its host plant, elderberry (Sambucus mexicana). Dust is listed in the species recovery plan as a threat to the VELB and unpaved surfaces are common throughout the riparian corridors where the VELB lives, yet the effects of dust on the VELB have been untested. We found that dust deposition varied among sites and was highest within 10 m of trails and roads, but was similar adjacent to dirt and paved surfaces within sites. Elderberry density did not differ with distance from dirt surfaces. Despite similar within-site dust levels, elderberry adjacent to paved surfaces were less stressed than those near dirt ones, possibly because increased runoff from paved surfaces benefited elderberry. Dust deposition across sites was weakly correlated with elderberry stress symptoms (e.g., water stress, dead stems, smaller leaves), indicating that ambient dust (or unmeasured correlates) influenced elderberry. Direct studies of the VELB showed that its distribution was not negatively affected by the proximity to dirt surfaces. Dust from low traffic dirt and paved access roads and trails, therefore, affected VELB presence neither directly nor indirectly through changed elderberry condition. These results suggest that the placement of VELB mitigation, restoration, and conservation areas can proceed independently of access roads if dust and traffic levels do not exceed those in our study site. Furthermore, dust control measures are likely to be unnecessary under such conditions. The potential effects of increased traffic and dust levels are addressed through a literature review.  相似文献   

6.
为分析铁尾矿路用对道路沿线土壤环境质量影响的程度,对铁尾矿化学成分及有害物质进行测定,以秦巴山区的山地黄棕壤作为道路建设的耕土环境,把铁尾矿按70%~90%的推荐比例掺入,铁尾矿中的重金属按照最不利的全浸入式扩散进行分析,对黄棕壤中重金属含量超过限制要求的重金属进行安全修复,使铁尾矿道路沿线黄棕壤的重金属含量满足限制要求。结果表明:铁尾矿硫化物含量高达到2.89%,不满足配制混凝土的硫化物限量要求;铁尾矿路用的土壤中重金属Cr最大含量103.24 mg/kg、Cu最大含量116.4 mg/kg,国评标准污染等级均为Ⅱ级,其余重金属元素含量都在国家标准正常范围以内;高生物量的非超富集植物、细菌微生物、城市的污泥、工业粉煤灰(5%粉煤灰+50%尾矿砂+45%黄褐土)能够很好修复重金属Cr、Cu污染的土壤;含钙类物质的钝化剂处置重金属Cr、Cu污染效果好,腐殖酸、凹凸棒土、膨润土可以钝化土壤中的重金属Cu;高生物量非超富集植物、微生物钝化剂联合使用,具有更好的修复效果;当控制铁尾矿掺加比例不超过73%时,铁尾矿道路沿线的土壤重金属含量能够满足国家标准限值的要求。  相似文献   

7.
Polluting substances are spread as a consequence of the construction and use of roads. This article provides a summary of the substances with which traffic pollutes the environment on a local, regional and global level. The mechanisms of dispersion of pollutants to soil and groundwater are described. Based on environmental quality requirements established in rules and regulations in the Netherlands, the paper discusses mitigating measures necessary to limit the distribution of pollutants along highways. Most of the data in this article come from original research carried out by or by order of the Road and Hydraulic Institute. For comparison, other data from the Netherlands have been included. It is shown that source-oriented measures (volume and technical) will have more effect on environmental quality than measures with regard to treating runoff. The use of porous asphalt instead of nonporous asphalt on highways in the Netherlands has environmental benefits. The article also pays attention to combined use of the roadside verges for treatment of runoff using ecological engineering techniques in the form of natural processes in helophyte filter systems in combination with enhancement of ecological values along highways.  相似文献   

8.
The purpose of this study is to evaluate the methods of reducing elevated-road traffic-noise levels in rural residential areas by controlling the relative locations and morphological parameters and to investigate the effect of noise barriers on noise attenuation along elevated roads and building facades in villages. This study selected six morphological parameters and used noise-mapping techniques to estimate the noise attenuation in 60 village sites. The results indicate that ‘quiet areas’ increase by approximately 10% for each additional 100 m increase in the distance between the elevated road and the village. The best strategy for noise reduction is keeping the elevated road 1,000 m away from the village and raising the road height to 20 m. The building façade conditions only affect the traffic noise level attenuation when the buildings are within 100 m of the elevated road. It was found that the cost-effective length of the road noise barrier is 600 m on both sides of the village parallel to the road. The results highlight the importance of using morphology to improve the traffic noise resistance of villages. The landscape shape indices of buildings and roads are the most important parameters that affect the traffic noise attenuation of elevated roads.  相似文献   

9.
Roads function as prime habitats and corridors for invasive plant species. Yet despite the diversity of road types, there is little research on the influence of these types on the spread of invaders. Common ragweed (Ambrosia artemisiifolia), a plant producing large amounts of allergenic pollen, was selected as a species model for examining the impact of road type on the spread of invasive plants. We examined this relationship in an agricultural region of Quebec, Canada. We mapped plant distribution along different road types, and constructed a model of species presence. Common ragweed was found in almost all sampling sites located along regional (97%) and local paved (81%) roads. However, verges of unpaved local roads were rarely (13%) colonized by the plant. A model (53% of variance explained), constructed with only four variables (paved regional roads, paved local roads, recently mown road verges, forest cover), correctly predicted (success rate: 89%) the spatial distribution of common ragweed. Results support the hypothesis that attributes associated with paved roads strongly favour the spread of an opportunistic invasive plant species. Specifically, larger verges and greater disturbance associated with higher traffic volume create propitious conditions for common ragweed. To date, emphasis has been placed on controlling the plant in agricultural fields, even though roadsides are probably a much larger seed source. Strategies for controlling the weed along roads have only focused on major highways, even though the considerable populations along local roads also contribute to the production of pollen. Management prioritizations developed to control common ragweed are thus questionable.  相似文献   

10.
四川省高等级公路环保现状与存在问题   总被引:1,自引:0,他引:1  
宋国平  刘国东 《四川环境》2002,21(4):62-64,76
自1990年以来,四川省高等级公路发展迅速,已建成近2000公里,同时,公路环保也取得了很大成就,所有高等级公路都编制了环评报告书,边坡,中央分隔带和互通式立交区的绿化率达70%以上,路边30m范围内重要敏感点或迁移或受到保护,服务区污水处理后达标排放,取弃土场施行绿化或复耕,水土流失得到治理,但建设期的环境管理还有待加强,环保绿化技术尚须进一步提高,环境监理要尽快开展。  相似文献   

11.
Open road tolling (ORT) design has been considered as an effective means of smoothing highway traffic and reducing travel delay on toll highways. In this paper it is demonstrated that ORT can also achieve significant air quality benefits over the conventional toll plaza design. The near roadside carbon monoxide (CO) concentration levels can be reduced by up to 37%, and diesel particulate matter (DPM) emissions can decrease by as much as 58%. These large expected air quality benefits have great implications to the regional efforts of reducing mobile source air pollution toward achieving attainment status and healthier living environment.  相似文献   

12.
Air pollution in the areas affected by the Great Hanshin Earthquake (Hyogo, Japan) of 17 Jan. 1995 was quite serious. We performed three investigations of dust. In the first investigation, we measured the total suspended particulate (TSP) concentration in the greatly damaged areas, located around the Sannomiya Station where a few hundred thousand people walked by during the daytime of 3 February. The maximum concentration at five points reached 150 microg/m3. In the second investigation, eight samples, which were classified into three groups (concrete, mortar, and soil dusts) as sources, were analyzed elementally by X-ray fluorescence. The elements found in concrete dust (Ca and S) were similar to those found in mortar dust. These differed from those found in soil dust (Ti, Fe, and Zr). The elements found in soil dust were important from the viewpoint of heavy metal contamination. In the third investigation, the alkalinity of concrete dust was observed by dissolution. This solution was equivalent to pH 11 to 12 and electrical conductivity 20 to 30 microS/m. We suspect that the alkaline component in the dust from debris in all the devastated areas was approximately comparable with the alkaline solution by which the acid rain falling over the Hanshin district of Osaka Megalopolis in one year could be neutralized into water of pH 7.0.  相似文献   

13.
Summary Population exposure to toxic chemicals in the environment has become one of the most important, if not the most important, environmental issue of the 1980's. In response to finding high cancer mortality rates, the State of New Jersey organized an extensive program of research to determine public exposure to toxic substances in the environment. Three parts of that research are described. One focusing on toxic substances in the water has detected very low concentrations of many substances. These substances tend to be found in three distinct chemical groups: pesticides, light chlorinated hydrocarbons, and heavy metals. Gross pesticide contamination tends to occur in agricultural and forest areas; gross light chlorinated hydrocarbon pollution is in urban areas. The second component of the research is toxic substances in the air. Like the water studies, low levels of contamination have been found. Limited sampling to date has found groupings of ubiquitous organic chemicals in urban areas, two groups of specialized organic chemicals near industrial sites, and high lead levels near major highways. The third project is developing a computerized information bank about the use and disposal of 155 chemicals and will look for associations between industrial disposal practices and contamination of the environment.  相似文献   

14.
Solid waste management is one of the major environmental concerns around the world. Cement kiln dust (KKD), also known as by-pass dust, is a by-product of cement manufacturing. The environmental concerns related to Portland cement production, emission and disposal of CKD is becoming progressively significant. CKD is fine-grained, particulate material chiefly composed of oxidized, anhydrous, micron-sized particles collected from electrostatic precipitators during the high temperature production of clinker. Cement kiln dust so generated is partly reused in cement plant and landfilled. The beneficial uses of CKD are in highway uses, soil stabilization, use in cement mortar/concrete, CLSM, etc.Studies have shown that CKD could be used in making paste/mortar/concrete. This paper presents an overview of some of the research published on the use of CKD in cement paste/mortar/concrete. Effect of CKD on the cement paste/mortar/concrete properties like compressive strength, tensile strength properties (splitting tensile strength, flexural strength and toughness), durability (Freeze–thaw), hydration, setting time, sorptivity, electrical conductivity are presented. Use of CKD in making controlled low-strength materials (CLSM), asphalt concrete, as soil stabilizer, and leachate analysis are also discussed in this paper.  相似文献   

15.
Solid waste management is one of the major environmental concerns around the world. Cement kiln dust (KKD), also known as by-pass dust, is a by-product of cement manufacturing. The environmental concerns related to Portland cement production, emission and disposal of CKD is becoming progressively significant. CKD is fine-grained, particulate material chiefly composed of oxidized, anhydrous, micron-sized particles collected from electrostatic precipitators during the high temperature production of clinker. Cement kiln dust so generated is partly reused in cement plant and landfilled. The beneficial uses of CKD are in highway uses, soil stabilization, use in cement mortar/concrete, CLSM, etc.Studies have shown that CKD could be used in making paste/mortar/concrete. This paper presents an overview of some of the research published on the use of CKD in cement paste/mortar/concrete. Effect of CKD on the cement paste/mortar/concrete properties like compressive strength, tensile strength properties (splitting tensile strength, flexural strength and toughness), durability (Freeze–thaw), hydration, setting time, sorptivity, electrical conductivity are presented. Use of CKD in making controlled low-strength materials (CLSM), asphalt concrete, as soil stabilizer, and leachate analysis are also discussed in this paper.  相似文献   

16.
根据大庆油田主要交通干线噪声的监测结果与机动车流量、重车率、机动车运行速度及道路宽度等因素进行相关分析,找出了影响交通噪声的主要因素。回归分析表明:交通噪声与上述4个参数均呈正相关,其中机动车流量、道路宽度对交通噪声的影响较小,机动车运行速度对交通噪声的影响较大,对交通噪声影响最大的是重车率。根据分析结果,提出了交通噪声预测模式及控制交通噪声的建议。  相似文献   

17.
Soils of the Pampas show no signs of contamination with potentially toxic elements (PTEs), except in the areas that surround cities. The concentration of PTE in crops grown in this region is in most cases unknown. Our objective was to determine the PTE concentration in main field crops and pastures grown in 'a priori' non-contaminated areas and in potentially contaminated areas around cities. Forty-eight plots from farms located far from cities or roads and 36 plots from farms located very close to cities or to high traffic roads were sampled. The area ranged from 33 degrees 40' S to 36 degrees 0' S and from 57 degrees 35' W to 61 degrees 22' W. Maize, soybean, wheat, grazed grassland and pastures, and their top soils were sampled. All samples were acid digested. Cadmium, zinc, chromium, copper, nickel and lead were determined using ICPES. Standard t-tests were performed. All soils were within the known normal values of soil PTE concentrations, with the exception of a few cases around cities. PTE accumulation on grains and aerial biomass is considered almost negligible in crops grown in both studied areas, with the exception of a few elements in soybean. PTE concentrations in crops and pastures are in keeping with the low content of trace metals found in soils of the Pampas.  相似文献   

18.
Highway stormwater runoff quality data were collected from throughout California during 2000-2003. Samples were analyzed for conventional pollutants (pH, conductivity, hardness, and temperature); aggregates (TSS, TDS, TOC, DOC); total and dissolved metals (As, Cd, Cr, Cu, Ni, Pb, and Zn); and nutrients (NO(3)-N, TKN, total P, and ortho-P). Storm event and site characteristics for each sampling site were recorded. A statistical summary for chemical characteristics of highway runoff is provided based on statewide urban and non-urban highways. Constituent event mean concentrations (EMCs) were generally higher in urban highways than in non-urban highways. The chemical characteristics of highway runoff in California were compared with national highway runoff chemical characterization data. The results obtained in California were generally similar to those found in other states. The median EMC for Pb measured in studies conducted in previous decades was much higher than the current median Pb EMC in California. The lower Pb EMC in California compared to previous highway runoff monitoring is believed to be due to the elimination of leaded gasoline. An attempt was also made to identify surrogate constituents within a general family of water quality categories using Spearman correlations and selected pairs with Spearman coefficients greater than 0.8. The strongest correlations were observed among parameters associated with dissolved minerals (EC, TDS, and chloride); organic carbon (TOC and DOC); petroleum hydrocarbons (TPH and O & G); and particulate matter (TSS and turbidity). Within the metals category, total iron concentration was highly correlated with most total metal concentrations. The correlations between total and dissolved concentrations were all less than 0.8, even between total and dissolved concentrations of the same metals. Multiple linear regression (MLR) analyses were performed to evaluate the impact of various site and storm event variables on highway runoff constituent EMCs. Parameters found to have significant impacts on highway runoff constituent EMCs include: total event rainfall (TER); cumulative seasonal rainfall (CSR); antecedent dry period (ADP); contributing drainage area (DA); and annual average daily traffic (AADT). Surrounding land use and geographic regions were also determined to have a significant impact on runoff quality. The MLR model was also used to predict constituent EMCs. Model performance determined by comparing predicted and measured values showed good agreement for most constituents.  相似文献   

19.
Various wastes and by-product materials are generated in the Sultanate of Oman including reclaimed asphalt pavement (RAP) aggregate, demolition concrete, cement by-pass dust (CBPD), copper slag, petroleum-contaminated soils (PCS), discarded tires, incinerator ash, and others. Recycling of such materials in construction is not practiced. Research data are also minimal into the potential use of selected materials in construction applications. This paper will present the results of several laboratory studies conducted into the use of PCS in asphalt concrete mixtures; on the use of CBPD in soil stabilization and flowable fill mixtures; on the utilization of copper slag and CBPD as cementitious materials; on the use of incinerator ash in cement mortars; and on the use of RAP aggregate in road bases and sub-bases. Laboratory data generally indicate that it is feasible to partially reuse some of these materials in construction provided that economic incentives and environmental concerns are taken into consideration.  相似文献   

20.
分析了沥青混凝土搅拌设备的构成以及生产沥青混凝土的工艺及烟尘特点;通过应用工程实例,指出袋式除尘器是沥青混凝土搅拌设备最理想的除尘系统之一。  相似文献   

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