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1.
Timber harvesting and oil and gas extraction create ecological change beyond just the footprint of the resource extraction. These activities also create a permanent network of roads that can have lasting effects on forest ecology. Grizzly bears (Ursus arctos) suffer higher mortality when in close proximity to roads, yet bears in the foothills of west-central Alberta, continue to use these high-risk areas. We examined the hypothesis that bears were not necessarily attracted to logging roads but that these roads were placed in habitats that bears preferred. Using a resource selection function, we examined patterns in road placement and identified areas that had characteristics similar to roaded habitats (henceforth road-like habitats). We then quantified grizzly bear response to roads and road-like habitats. Of the 30 bears sampled, we found that 17 selected areas closer to roads than random and 11 selected road-like habitats. Road-like habitats were selected by subadults and some adult females but were not a good predictor of adult male habitat selection. Seasonally, grizzly bears selected habitats closer to roads in spring and early summer but selected road-like habitats more in late summer and fall, indicating that bears may be attracted to disturbed habitats in spring and undisturbed habitats in fall. We conclude that roaded habitats were selected by some grizzly bears but road placement in low-elevation valleys alone does not account for the strong selection preference. Although road placement likely plays a role, other factors such as clearcut association with roads may compound the attractiveness of roaded habitats to grizzly bears. The tradeoff between mortality risk and high-quality forage near roads must be addressed to prevent these areas from acting as attractive sinks.  相似文献   

2.
We examined if clearcuts were selected as habitats by grizzly bears (Ursus arctos L.) in west-central Alberta during three seasons: hypophagia, early hyperphagia, and late hyperphagia. Our objectives were to describe seasonal habitat selection of clearcuts using resource selection functions at two scales. At the first scale, we assessed patch or third-order selection by comparing use (radiotelemetry) with study area-wide random locations and a dummy variable identifying whether locations occurred within or outside of clear-cut boundaries. At the second scale, we assessed within-patch or fourth-order selection by comparing locations (use and random) found within clearcuts and environmental covariates of terrain, silviculture, and landscape metrics. Finally, we examined diurnal versus crepuscular/nocturnal use of clearcuts by comparing the two with an expected 50:50 ratio.At the third-order scale, grizzly bears used clearcuts with respect to their availability for hypophagia and late hyperphagia, while selecting clearcuts more than expected during early hyperphagia. Fourth-order habitat selection revealed that landscape metrics, silviculture, and terrain were important predictors of grizzly bear use during hypophagia and late hyperphagia, while terrain appeared to be the most important predictor during early hyperphagia. Overall, grizzly bears avoided clear-cut interiors and preferred clearcuts with higher perimeter-to-edge ratios. Clearcuts were significantly more likely to be used during crepuscular/nocturnal periods. Intermediate-aged (∼30 years old) clearcuts were selected during hypophagia, whereas recent and old clearcuts were selected during late hyperphagia. Bears tended to avoid clearcuts with Donaren mound preparation, while selecting clearcuts with Bracke or shark-fin barrel dragging. These results suggest that landscape metrics, site preparation history, terrain, and season were important factors determining the use of clearcuts by grizzly bears. Future forest planning should strive to maximize habitat quality by: (1) increasing perimeter-to-edge ratio for clear-cut shapes; (2) using low impact and/or positively associated site preparation treatments like Bracke and shark-fin barrel dragging; and (3) limiting human access to areas predicted as high-quality habitat.  相似文献   

3.
Roads and topography can determine patterns of land use and distribution of forest cover, particularly in tropical regions. We evaluated how road density, land use, and topography affected forest fragmentation, deforestation and forest regrowth in a Brazilian Atlantic Forest region near the city of São Paulo. We mapped roads and land use/land cover for three years (1962, 1981 and 2000) from historical aerial photographs, and summarized the distribution of roads, land use/land cover and topography within a grid of 94 non-overlapping 100 ha squares. We used generalized least squares regression models for data analysis. Our models showed that forest fragmentation and deforestation depended on topography, land use and road density, whereas forest regrowth depended primarily on land use. However, the relationships between these variables and forest dynamics changed in the two studied periods; land use and slope were the strongest predictors from 1962 to 1981, and past (1962) road density and land use were the strongest predictors for the following period (1981–2000). Roads had the strongest relationship with deforestation and forest fragmentation when the expansions of agriculture and buildings were limited to already deforested areas, and when there was a rapid expansion of development, under influence of São Paulo city. Furthermore, the past (1962) road network was more important than the recent road network (1981) when explaining forest dynamics between 1981 and 2000, suggesting a long-term effect of roads. Roads are permanent scars on the landscape and facilitate deforestation and forest fragmentation due to increased accessibility and land valorization, which control land-use and land-cover dynamics. Topography directly affected deforestation, agriculture and road expansion, mainly between 1962 and 1981. Forest are thus in peril where there are more roads, and long-term conservation strategies should consider ways to mitigate roads as permanent landscape features and drivers facilitators of deforestation and forest fragmentation.  相似文献   

4.
We compared stand structure and plant species occurrence on the shoulders of 3-, 10- and 20-year-old roads in a subtropical evergreen broad-leaved forest to document temporal changes in edge effects of forest roads. We recorded 154 vascular species in the study plots, including 3 non-native species. We used generalized linear mixed models to analyze changes in forest structure and plant species composition in relationship to the distance from forest roads. The spatial patterns in stand structure at different distances from roads differed with road age. The large canopy openness on the edge of 3-year-old roads decreased with time after the construction. A progressive decrease in tree height on roadsides was observed after the road construction, suggesting tall trees could not withstand the dry and windy roadside environment. The edge effect on the canopy tended to be larger at higher elevation sites. The spatio-temporal pattern of species occurrence based on distance from roads differed by species. Typical pioneer species such as Schima wallichii and Eurya japonica increased along the edge, while less aggressive pioneer species and understory species decreased. As time passed after the road construction, some climax and understory species decreased at the forest edge, while other climax and understory species increased. The modeling methods proposed in this study could be applied to different roadside and edge study sites.  相似文献   

5.
国外林区道路发展现状及启示   总被引：4，自引：2，他引：2  
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100 m/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   

6.
The Rocky Mountains in Alberta, Canada are subject to a growing number of human activities that cause landscape disturbances. This region is important for large carnivore species such as grizzly bears, whose population decline is a serious management concern. Understanding the impact of landscape disturbance on grizzly bear habitat use is necessary to effectively manage this region and beyond. The goal of this research is to explore the spatial–temporal pattern of habitat use and to characterize the impact of disturbance on use through time. Research was conducted using radio-telemetry location data of female grizzly bears from 1999 to 2003. Kernel home ranges were created annually for three foraging seasons: hypophagia, early hyperphagia, and late hyperphagia. For each season, locations (30 m × 30 m grid cells) were characterized by the temporal persistence or variability in annual use by grizzly bears. Spatial–temporal trends were then compared for disturbed and undisturbed landscapes. Results indicate that in some foraging seasons, particularly hypophagia, the grizzly bear population's use of disturbed areas was proportionally higher than use in undisturbed areas. In other foraging seasons the trends are less clear, but all show instances of preferential selection of disturbed areas. Given that grizzly bear mortality tends to rise when bears use disturbed areas, this preferential selection of disturbed areas is a management concern. To enhance conservation efforts it may be beneficial to control human use in high-quality habitats. This protection may be most important for high-quality habitats used in the spring, as bears appeared to use smaller areas during this period.  相似文献   

7.
Predation risk is an important factor influencing the distribution of ungulates and their impact on forest structure. However, simultaneous predation risk by wolves and humans is rarely considered in the analyses of habitat selection by ungulates. We counted ungulate pellets on transects to analyse the influence of wolves and humans on ungulate density distribution in the Białowieża Forest, Poland. We assessed whether (1) forest exploitation influenced ungulate habitat selection, (2) ungulate density was higher in areas without human hunting, (3) ungulates avoided the surroundings of a major road, (4) prey density was higher in the strife zone between home ranges of wolf packs both in the presence and absence of human hunting, (5) ungulates avoided areas selected by wolves, and (6) wolf kill sites were in high prey density areas. Red deer (Cervus elaphus) and wild boar (Sus scrofa) selected unexploited over exploited forests and areas without hunting, whereas roe deer (Capreolus capreolus) preferred exploited forests. Wild boar and European bison (Bison bonasus) avoided the area within 300 m of a major road, whereas we could not detect any avoidance by red or roe deer. Prey density was not higher in wolf strife zones, regardless of human hunting. Ungulates did not avoid areas selected by wolves. Wolves killed red deer in areas with prey density of about 4 red deer/km2, regardless of whether the average red deer density in those areas was higher or lower. We conclude that habitat alteration by forest exploitation and hunting by humans influenced the density distribution of ungulates more than predation risk by wolves.  相似文献   

8.
In this study, we combined a program to optimize forest road alignments with a method for prediction of surface erosion and related sediment delivered to streams. Combining the forest road design program with the high-resolution digital elevation model made it possible to estimate soil sediment based on a standard methodology, because a relatively accurate road prism could be generated. The combined program properly places and spaces drainage structures based on the Washington State Forest practice board manual. We applied the program to a part of Capitol State Forest in Washington State and optimized horizontal and vertical alignments while estimating movement of soil sediment from roads to streams. We discussed the effects of road surface materials, near-stream culvert distance to stream, and out-sloped forest road template on total road costs and soil sediment delivered to streams. Using lower quality rock surfacing reduced total costs, but the amount of soil sediment from lower quality rock surfacing was 1.5 times more than that on a higher quality rock traction surface. Therefore, lower quality rock surfacing should not be used near the stream. The placement of near-stream culverts 15 m upstream and out-sloped road template were examined using a traction surface on 15-m sections upstream and lower quality rock surfacing on other sections in order to reduce soil sediments to the stream and total costs. As a result, placing near-stream culverts 15 m upstream and using an out-sloped road template significantly reduced total road cost and soil sediment. Finally, we optimized horizontal and vertical alignments while limiting soil sediment to a specified maximum level. The model successfully optimized forest road alignments, which reduced total road cost as well as soil sediment.  相似文献   

9.
Roads are recognised as having different ecological roles such as barrier, corridor or habitat, but the spatial extent of road effects on plant communities in forests remains unclear. We studied the effect of forest road distance on plant understory diversity at 20 sites in young and adult oak stands in a French lowland forest with a long history of management and road construction. All vascular and bryophyte species were collected at five distances ranging from the road verge to 100 m into the adjacent forest stand. We analysed species composition, individual species response, a priori life-history traits response – life form, habitat preference and dispersal mode – and environmental indicator values in relation to road distance and stand age. Plant composition strongly differed between road verge and forest interior habitats. The main road effect extended less than 5 m into the forest stand. A third habitat was detected at the forest-road edge resulting from the road effect on light and soil conditions, and from edge-specific topography. Non-forest species were almost absent from the forest interior. In contrast, many bryophytes and several vascular plants kept away from the road. We identified a posteriori six species groups that better explained the variability of plant response profiles than a priori life-history traits. Plant response to road distance was also dependent on stand age: some species colonised from the road into the forest interior in young stands following regeneration cutting, while other species displayed the reverse pattern in adult stands once canopy closed above the forest road. Even if the depth of forest road effect measured in lowland managed stands was narrow, building of a new forest road has non-negligible effects on plant population dynamics. Forest managers should take into account the impacts of roads on biodiversity, since the expected intensification of silviculture in response to global changes is set to accentuate the effect of forest roads. We recommend further study on the role of dispersal by vehicles (i.e. agestochory) in road effects.  相似文献   

10.
A forest road network in northeastern Italy was explored by field investigations to evaluate the cost of covering annual demand of woodchips according to three scenarios. The first scenario (A) considered the current extent of the forest road network (mainly tractor road) and the associated qualitative characteristics; the second scenario (B) evaluated the possibility of increasing the availability of the technical amount of forest biomass by extending the forest road network by three tractor roads (3.9 km); the third scenario (C) considered the impact on woodchip supply of converting 9.3 km of tractor forest road into truck forest road. At a woodchip price of 60 € t−1, the cost–supply curve of scenario C indicated a woodchip amount of 2886 t year−1, which was 561 t year−1 greater than scenario A and 161 t year−1 greater than scenario B.  相似文献   

11.
It has been suggested that during the past several decades, the frequency and the intensity of wildfires have markedly increased in the Mediterranean basin. We came to assess this postulation in the forested region of Mount Carmel, Israel. This region is characterized by Quercus spp. and Pistacia spp. maquis and has been intensely afforested with Pinus spp. stands since the 1920s. We compiled a GIS-based database of the fires recorded in the region since 1983, in addition to archiving data beginning from the 1940s. The data were collected from land stewardship agencies’ archives, fire departments and aerial photographs. Prior to the early 1980s, no systematic documentation of the fires was available, rather just sporadic qualitative documentation of the large forest fires that occurred. Between 1944 and 1982, only 6 large fires were documented, while after that 11 large fires occurred. Analysis indicated that the spatial distribution of the fires does not occur at random, and their locations are significantly closer to roadsides compared to an expected random distribution. The annual number of fires and the areas burned during the last two decades were not correlated with annual precipitation in any manner. Accordingly, we suggest that the increased number of large forest fires during the last decades is associated with the maturation and senescence of the planted forest coupled with increased human activities.  相似文献   

12.
An experiment was conducted in southern Chile to study the effect of tree cover (0 or 200 stems of 13-year-old Pinus radiate/ha), grazing severity (8 or 12 cm height at commencement of grazing by sheep) and fertilizer application rate (low or high) on the establishment and growth of Lotus uliginosus and Trifolium subterraneum, when sown in conjunction with Festuca arundinacea. The establishment of both legumes was greater in the agroforestry than the open field, and the percentage of viable seeds that were established was greater for Trifolium than Lotus. Festuca established better when sown in conjunction with Lotus in the open field. During the two years after stand establishment there was a greater reduction in the ground cover and dry matter (DM) yield of both legumes, but in particular Trifolium, in the agroforestry than in the open field. In the second year of grazing Trifolium contributed less than 9% of total DM yield in the agroforestry, compared with 22% for Lotus. The ground cover of Lotus was increased by a tall grazing height in the agroforestry, whereas Trifolium increased its cover when the grazing height was short. Additional fertilizer at establishment had a greater effect in increasing herbage yield in the open field than in agroforestry. It is concluded that both Lotus and Trifolium establishments are greater in agroforestry than in an open field, but that in agroforestry there is a reduction in legume yield over time, particularly of Trifolium. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

13.
Controversy surrounds postfire logging, often because of negative effects on snag-dependent wildlife species. Few studies, however, have examined effects on early-seral species that may benefit from postfire logging, nor effects on trophic relationships. We studied the effects of postfire logging on trophic dynamics between wolves (Canis lupus), three ungulate species and ungulate forage biomass during the first 3 years in a large burn in the Canadian Rockies, Alberta, Canada. We examined plant biomass and ungulate responses to two treatments (post- and prefire logging) compared to a burned but unlogged area (control). We evaluated resource selection for the three treatments by elk (Cervus elaphus) using radiotelemetry and for deer (Odocoileus spp.), moose (Alces alces), and, secondarily, elk using pellet counts. Elk resource selection was modeled as a function of the trade-off between wolf predation risk and herbaceous forage biomass to test for trophic impacts of postfire treatments. Postfire logging had transient effects on total herbaceous biomass; while forb biomass was reduced, increases in graminoid biomass more than compensated by the third year. Prefire logging areas were dominated by a few species, but had generally higher forage biomass by the third year. Ungulates avoided postfire and prefire logged areas despite greater herbaceous biomass. Only when we considered elk resource selection as a function of both forage and wolf predation risk was the extent to which trophic interactions affected by postfire logging revealed. Wolves selected proximity to roads and the higher forage biomass associated with postfire logging in open logged areas. This translated to the highest predation risk for elk in postfire logged areas. Thus, ungulates avoided postfire logged areas because of human alteration of top-down predation risk despite enhancements to bottom-up forage biomass. Managers should consider trophic consequences of postfire logging on the interactions among species when gauging logging effects on terrestrial ecosystems. Making use of existing roads, minimizing the construction of new roads, and managing road removal following postfire logging will help mitigate the negative effects of postfire logging on terrestrial ecosystems.  相似文献   

14.
Xu Li  Li Li  Yang Xiujuan 《林业研究》1997,8(2):115-116
From 1991 to 1992, we observed behavior of 7 brown bears (5 females, 2 males) in mating season. Results showed that the oestrus of brown bears was mainly from May to July. The oestrus of most individuals occurred at the end of May and the beginning of June. There were some differences in the oestrus among individuals. Average duration of the oestrus was 30.8 days (16–50 days). The mating behavior was mainly observed during 8.00–9.00 a.m., and 15.00–16.00 p.m., Rest and sleep were the next behavior after mating for most bears, especially for male bears. All bears had poor appetite. The pattern and process of a successful mating was that a male bear approached a female, smelled the pudendum of the female, climbed on female hip, mated, parted and rested. Oestrus females approached males sometimes. (Responsible Editor: Sun Yueqi)  相似文献   

15.
Researchers and managers undertaking wildlife habitat assessments commonly require spatially explicit environmental map layers such as those derived from forest inventory and remote sensing. However, end users of geospatial products must often make choices regarding the source and level of detail required for characterizing habitat elements, with few published resources available for guidance. We appraised three environmental data sources that represent options often available to researchers and managers in wildlife ecological studies: (i) a pre-existing forest inventory; (ii) a general-purpose, single-attribute remote sensing land cover map; and (iii) a specific-purpose, multi-attribute remote sensing database. The three information sources were evaluated with two complementary analyses: the first designed to appraise levels of map quality (assessed on the basis of accuracy, vagueness, completion, consistency, level of measurement, and detail) and the second designed to assess their relative capacity to explain patterns of grizzly bear (Ursus arctos) telemetry locations across a 100,000-km2 study area in west-central Alberta, Canada. We found the forest inventory database to be reasonably functional in its ability to support resource selection analysis in regions where coverage was available, but overall, the data suffered from quality issues related to completeness accuracy, and consistency. The general-purpose remote sensing land cover product ranked higher in terms of overall map quality, but demonstrated a lower capacity for explaining observed patterns of grizzly bear habitat use. We found the best results using the specific-purpose, multi-attribute remote sensing database, and recommend that similar information sources be used as the foundation for wildlife habitat studies whenever possible, particularly those involving large areas that span jurisdictional boundaries.  相似文献   

16.
为探讨马尾松不同类型林地土壤微生物区系及其季节变化,对三峡库区云阳县马尾松近熟龄天然林、中龄天然林和人工林林地土壤可培养细菌、芽孢杆菌(Bacillus spp.)和真菌进行了分析。结果表明,林地土壤微生物优势种群种类和数量因不同森林类型林地和季节有所差异。中龄天然林的细菌数量显著高于近熟龄天然林和人工林,其四季变化也最大,而近熟龄天然林和人工林则相对平缓。林地土壤细菌优势种群主要是芽孢杆菌(Bacillus spp.)和假单胞菌(Pseudomonas spp.),尤以蜡状芽孢杆菌(Bacillus cereus)居多,在四季中冬季细菌的优势种群数量所占比例最高(近熟龄天然林＞人工林＞中龄天然林),优势种群近熟龄天然林为芽孢杆菌,占39.74%;人工林为假单胞菌,占37.26%;中龄天然林为蜡状芽孢杆菌,占24.91%。三种林地类型土壤的芽孢杆菌在不同季节都以蜡状芽孢杆菌(占20% - 49%)和芽孢杆菌科(Bacillaceae)一种(种名未定)为优势种群。三种林地类型土壤真菌优势种群在秋季所占比例最高,且人工林＞近熟龄天然林＞中龄天然林;优势种群数量及所占比例人工林为核盘菌(Sclerotinia sclerotiorum),33.08%,近熟龄天然林为核盘菌, 31.7%,中龄天然林为瓦克青霉(Penicillium waksmanii), 25.15%。  相似文献   

17.
To better understand tree regeneration trajectories and the resultant coexistence of Abies with co-dominants, Picea jezoensis var. hondoensis, Tsuga diversifolia and Betula ermanii, in an old-growth subalpine forest, we investigated spatial mortality patterns during the regeneration of Abies mariesii and A. veitchii, which are abundant in the understory reflecting their shade tolerance. Regeneration of these Abies spp. from shaded understory to canopy status is affected by other canopy co-dominants. Snags of understory Abies spp. were common, suggesting that the primary mortality agent is suppression by the overstory. Although live, small Abies trees in the understory were positively associated with a Picea canopy, the long-term survival was reduced among Abies trees close to the canopy, suggesting that shading by large Picea in the overstory negatively affects understory Abies plants. The existence of shade-intolerant canopy co-dominants such as Picea and also Tsuga, which are larger and longer lived than the shade-tolerant Abies, may play an important role in preventing the Abies spp. from competitively displacing these other tree species, which are much rarer in the understory, though common in the canopy. Moreover, in spite of the fact that Betula canopies fostered recruitment and growth of Abies saplings, Abies showed no association with Betula canopy and their survival at later-stage was rather reduced near or beneath Betula canopies at the subsequent understory small tree stage. Based on spatially significant events related to tree death, this study detected such “habitat shifts” in the trajectory of tree regeneration. Accordingly, it can be concluded that careful consideration of the regeneration habitat is required for a fuller understanding of ecological processes in spatially complex old-growth forest systems.  相似文献   

18.
林区道路是林场建设的主要内容之一,是决定林区经济能否顺利发展的重要因素。林区道路规划设计的合理与否,直接关系到整个林区产业的生产、发展和壮大。针对当前我国林业产业发展现状,笔者研究了林区道路规划设计中常遇到的重要问题,并结合实践经验提出了解决的办法,以供实践参考。  相似文献   

19.
Sustainable management of selectively logged tropical forests requires that felled trees are replaced through increased recruitment and growth. This study compares road track and roadside regeneration with regeneration in unlogged and selectively logged humid tropical forest in north-eastern Bolivia. Some species benefited from increased light intensities on abandoned logging roads. Others benefited from low densities of competing vegetation on roads with compacted soils. This was the case for the small-seeded species Ficus boliviana C.C. Berg and Terminalia oblonga (Ruiz & Pav.) Steud. Some species, e.g. Hura crepitans L., displayed patchy regeneration coinciding with the presence of adult trees. Our results suggest that current management practices could be improved by intensifying logging in some areas to improve regeneration of light demanding species. Sufficient seed input in logged areas should be ensured by interspersing large patches of unlogged forest with logged areas. This may also assist regeneration of species that perform poorly in disturbed areas.  相似文献   

20.
北京市3种道路防护林春季滞尘规律研究   总被引：2，自引：1，他引：1       下载免费PDF全文
[目的]研究不同道路防护林的滞尘能力及滞尘的动态变化和空间分布规律。[方法]在春季对3种道路防护林(油松林、圆柏林、银杏林)距道路不同宽度的滞尘量进行连续观测,对比3种道路防护林滞尘能力,分析降雨、极大风速、相对湿度、PM10等因子对滞尘动态的影响以及3种道路防护林滞尘的空间分布特征。使用单位叶干质量滞尘量(mg·g-1)表征叶面滞尘能力。[结果]表明:(1)3种植物叶面滞尘能力差异显著,圆柏银杏油松,分别为4.79±0.20、2.48±0.07、1.42±0.04 mg·g-1,单株和单位林分面积滞尘量均为圆柏林油松林银杏林;(2)3种道路防护林在外界影响下滞尘量处于动态变化之中,油松林具有比银杏和圆柏林更高的滞尘稳定性;(3)降雨量较低时3种道路防护林滞尘量均增加,降雨量较高时3种道路防护林滞尘量均降低,油松和银杏林的滞尘量更容易受降雨影响而降低;随着风速增大,3种道路防护林滞尘作用不断加强,风速继续增大时,油松和圆柏林滞尘量均有减少,银杏林滞尘量仍有显著增加。(4)3种道路防护林滞尘量在五环路侧(北)均高于香山路侧(南),油松和圆柏林均呈现为道路防护林中间位置为最低点,银杏林中间位置滞尘量最高。(5)油松和圆柏林滞尘量外部比内部变化大,银杏林滞尘量内部比外部变化大。[结论]道路防护林的滞尘效益受树种、林分结构、所处环境、天气条件等多方面因素共同影响,在营建和管理过程中应充分考虑各种因素,充分发挥滞尘作用。  相似文献   

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