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1.
For large carnivores persisting in human-dominated landscapes, conservation planning is often hindered by the large spatial requirements of these species, availability of protected areas, and human land uses. Protected areas are usually too small to support viable populations, and scattered across a human land-use matrix. Therefore, large carnivore conservation should be planned at large spatial scales under a land-sharing approach (allowing the coexistence between large carnivores and people in the same landscape), which means increasing the focus on the human-dominated matrix. Most of the critical factors determining large carnivore persistence (i.e., those related to food availability and vulnerability to humans) interact synergistically in space and time during the breeding season. Here, using as a case study a wolf population in NW Iberia, we studied fine-scale breeding site selection patterns (1 and 9 km2) in relation to human pressure, and the availability of food and refuge. The selection of wolf breeding sites in this human-dominated landscape was not determined by potential availability of prey biomass in the immediate vicinity (1 km2). However, wolves selected breeding sites with high availability of refuge (concealing vegetation), and low human accessibility and activity levels. Paved roads showed the highest proportion of independent contribution to explaining breeding site selection patterns (negative influence), being followed by refuge availability (positive influence) and the remoteness of breeding sites in relation to the surrounding spatial context (positive influence). Refuge availability, even at very small spatial scales taking into account the spatial requirements of wolves, may compensate for moderate levels of human activities in the vicinity of breeding sites. The strength of breeding selection patterns varied along a hierarchical process at different spatial scales. Under a landscape-sharing approach, integrating key processes observed in the human-dominated matrix, such as breeding site selection patterns, into landscape planning is of paramount importance for carnivore conservation. By temporally restricting human use on breeding sites and small portions of surrounding lands (~ 1 km2), and by maintaining several small refuge areas interspersed within the human-dominated matrix, we could favor wolf persistence without reducing land availability for other uses, improving the conditions for coexistence between wolves and humans.  相似文献   

2.
Centuries of persecution have influenced the behaviour of large carnivores. For those populations persisting in human-dominated landscapes, complete spatial segregation from humans is not always possible, as they are in close contact with people even when they are resting. The selection of resting sites is expected to be critical for large carnivore persistence in human-dominated landscapes, where resting sites must offer protection to counteract exposure risk. Using wolves (Canis lupus) as a model species, we hypothesised that selection of resting sites by large carnivores in human-dominated landscapes will be not only influenced by human activities, but also strongly determined by cover providing concealment. We studied the fine-scale attributes of 546 wolf resting sites and confronted them to 571 random points in NW Iberia. Half of resting sites (50.8 %) were found in forests (mainly forest plantations, 73.1 %), 43.4 % in scrublands, and only 5.8 % in croplands. Compared to random points, wolves located their resting sites far away from paved and large unpaved roads and from settlements, whereas they significantly selected areas with high availability of horizontal (refuge) and canopy cover. The importance of refuge was remarkably high, with its independent contribution alone being more important than the contribution of all the variables related to human pressure (distances) pooled (51.1 vs 42.8 %, respectively). The strength of refuge selection allowed wolves even to rest relatively close to manmade structures, such as roads and settlements (sometimes less than 200 m). Maintaining high-quality refuge areas becomes an important element to favour the persistence of large carnivores in human-dominated landscapes as well as human-carnivore coexistence, which can easily be integrated in landscape planning.  相似文献   

3.
Reproductive success is crucial for the survival and persistence of any species. The Deccan Biogeographic Zone of India is the stronghold of a population of the Indian wolf Canis lupus pallipes . Gaining a better understanding of the den-use pattern of wolves in different areas in this zone is thus vital for their conservation and management. The wolves excavated multiple dens in our study sites and kept shifting their litters among them. Major disturbance factors around denning sites were active stone quarries, traffic, crop harvesting and livestock movement. One wolf pack used 14 dens in four breeding seasons. Discriminant function analysis indicated that den shifting by wolves was not entirely governed by disturbance levels at den sites. Increasing age of pups was one of the main factors associated with den shifting rather than the magnitude of disturbance ( χ 2=34.26, d.f.=12, P <0.001). Tolerance to disturbance around dens during the early stages of pup development was negatively correlated ( r =−0.519, P <0.05) with availability of water and age of pups ( r =−0.613, P <0.01). Excavation of multiple dens by wolves was apparently related to den shifting, which seemingly is a survival strategy of wolves in these semi-wild human-dominated landscapes in the Deccan Biogeographic Zone. Principal components analysis indicated that during the initial stages of pup development, nature of the land, den orientation and distance of the den from roads were important cues in addition to age category of pups for den shifting. The analysis also suggested that factors such as distance of the new den where pups are to be transferred, distance from water source and availability of fox Vulpes bengalensis holes for den use were also important.  相似文献   

4.
Wildlife conservation in human-dominated landscapes requires that we understand how animals, when making habitat-use decisions, obtain diverse and dynamically occurring resources while avoiding risks, induced by both natural predators and anthropogenic threats. Little is known about the underlying processes that enable wild animals to persist in densely populated human-dominated landscapes, particularly in developing countries. In a complex, semi-arid, fragmented, human-dominated agricultural landscape, we analyzed the habitat-use of blackbuck, a large herbivore endemic to the Indian sub-continent. We hypothesized that blackbuck would show flexible habitat-use behaviour and be risk averse when resource quality in the landscape is high, and less sensitive to risk otherwise. Overall, blackbuck appeared to be strongly influenced by human activity and they offset risks by using small protected patches (~3 km2) when they could afford to do so. Blackbuck habitat use varied dynamically corresponding with seasonally-changing levels of resources and risks, with protected habitats registering maximum use. The findings show that human activities can strongly influence and perhaps limit ungulate habitat-use and behaviour, but spatial heterogeneity in risk, particularly the presence of refuges, can allow ungulates to persist in landscapes with high human and livestock densities.  相似文献   

5.
Aim Understanding which human or environmental factors interact to enable or to limit the occurrence and persistence of large carnivores in human‐dominated landscapes is an important issue for their effective conservation, especially under the current scenario of global change where most of their former habitat is being transformed by humans. Location NW Iberian Peninsula. Methods We combine data on the distribution of Iberian wolves (Canis lupus signatus) living in a human‐dominated landscape in NW Spain and variation and partitioning methods to investigate the relative importance of three groups of predictors: food availability, humans and landscape attributes – each group expected to have unequal effects on wolf reproduction and survival – and their interactions on the occurrence of this species. Results We found that the group of predictors related with landscape attributes (altitude, roughness and refuge) strongly determined wolf occurrence, followed by humans and food availability. Variance partitioning analysis revealed that the three most important components determining wolf occurrence were related with landscape attributes: (1) the joint effects of the three predictor groups, (2) the joint effect of humans and landscape attributes and (3) the pure effect of landscape attributes. Altitude had the main independent contribution to explain the probability of wolf occurrence. Main conclusions In human‐dominated landscapes, the occurrence of wolves is the result of a complex interaction among several environmental and human factors. Our results suggest that the characteristics of the landscape (spatial context) – factors associated with the security of wolves facilitating that animals go unnoticed by humans, wolf movements, dispersal events and short‐time colonization – become more important in human‐dominated landscapes and may have played a key role in the occurrence and persistence of this species throughout decades modulating the relationship between humans and wolf distribution.  相似文献   

6.
Fragmentation of native habitats is now a ubiquitous phenomenon affecting wildlife at various scales. We examined selection of den-sites (n = 26) by Indian foxes (Vulpes bengalensis) in a highly modified short-grassland landscape in central India (Jan-May, 2010). At the scale of the home-range, defined by an 800 m circular buffer around den sites, we examined the effect of land-cover edges and roads on selection of sites for denning using a distance-based approach. At the smaller den-area scale, defined by a 25 m x 25 m plot around den and paired available sites, the effect of microhabitat characteristics was examined using discrete-choice models. Indian foxes selected den-sites closer to native grasslands (t = -9.57, P < 0.001) and roads (t = -2.04, P = 0.05) than random at the home-range scale. At the smaller scale, abundance of rodents and higher visibility increased the odds of selection of a site by eight and four times respectively, indicating resource availability and predator avoidance to be important considerations for foxes. Indian foxes largely chose to den in human-made structures, indicated by the proportion of dens found in earthen bunds (0.69) and boulder piles (0.27) in the study area. With agricultural expansion and human modification threatening native short-grassland habitats, their conservation and effective management in human-dominated landscapes will benefit the Indian fox. The presence of some human-made structures within native grasslands would also be beneficial for this den-dependent species. We suggest future studies examine the impact of fragmentation and connectivity of grasslands on survival and reproductive success of the Indian fox.  相似文献   

7.
ABSTRACT Understanding den selection for the federally threatened Louisiana black bear (Ursus americanus luteolus) will assist managers in effectively managing bear populations and the landscapes they inhabit. We assessed den selection of 72 female Louisiana black bears at multiple spatial scales in northern and central Louisiana, USA. We used 230 den-years to examine den type preference, microhabitat characteristics of dens, and effects of landscape characteristics on den selection. We also evaluated reuse of tree dens and their availability across several study areas. Bears selected tree dens more frequently (65%) than ground dens. Most (55%) ground dens were associated with standing or downed trees, and most tree dens were in baldcypress (Taxodium distichum; 86%) or surrounded by water (80%). Selection of ground dens was positively associated with landscape metrics related to presence of water, whereas selection of tree dens was positively associated with proximity to edge and greater proportions of swamp and areas containing water. Reuse of tree dens averaged 15% (range = 0–20%) across study areas and our estimates of tree-den availability indicated that tree dens were not a limiting resource for Louisiana black bears in the northern or central portions of Louisiana. Although Louisiana black bears demonstrated plasticity in den selection, we recommend managers use forest management practices that conserve appropriate tree dens and create ground-denning opportunities, because both would promote the recovery of Louisiana black bear populations.  相似文献   

8.
The distribution of dens and den use by the red fox was studied in Kumamoto Prefecture between 1968 and 1982. A total of 80 dens were classified into natal, residential, and temporarily-visited dens. Natal dens comprised 12.4% of all dens. Relative proportions were quite stable for a long period. This indicates a constant number of reproducing females in the area for a considerable length of time. Seasonally the utilization of den showed three peaks in February, May and October. The peaks coincided well with the peaks of reproductive activity of female foxes. The results of multiple regression analysis of distribution of dens with respect to selected environmental parameters around densites indicated that the fox selectively utilize open land, rather than densely vegetated areas. The persistence of dens, the selective utilization by foxes of open land and the sizes of dens were all related to the breeding activities of female foxes inhabiting the area. Reproductive females usually used plural dens (“den group”) in one reproductive season. The numbers of those females occuring in the area were maintained at a steady level for fairy long periods. These indicate that the existence of a stable social relationship between females mediated through occupancy of “den groups.”  相似文献   

9.
Different patterns of the use of space by red foxes ( Vulpes vulpes ) depend mainly on the distribution and availability of food patches. Nevertheless, other key resources such as suitable areas for dens can also influence the territory size and social organization of this predator. In fact, landscape modifications such as habitat patchiness made by human activities (agricultural practices, urbanization) should create ample unfavourable zones for den settlement. Several studies focused on the distribution and use of dens by the red fox in different habitat types but we do not have any data on the den settlement and habitat composition in the semi-arid regions of North Africa. This study was carried out at Djerba island (SE Tunisia), virtually deprived of surface water and with a semi-arid climate because of the bordering Sahara desert. We used line and random transects to find fox dens. The spatial pattern of dens varied mainly in different habitat types and geoclimatic regions. Highly fragmented areas were also occupied by foxes that built dens close together inside small suitable patches. Fox dens had fewer entrances in more arid regions and they mainly faced the south. Habitat selection was influenced by water availability and irrigated tree plantations that modify soil textures allowing digging of dens. Moreover, asphalt roads limit den settlements. We suggest that the choice of denning sites by foxes depends on persisting harsh conditions and human activities.  相似文献   

10.

Land-use change has led to substantial range contractions for many species. Such contractions are particularly acute for wide-ranging large carnivores in Asia’s high altitude areas, which are marked by high spatiotemporal variability in resources. Current conservation planning for human-dominated landscapes often takes one of two main approaches: a “coexistence” (land sharing) approach or a “separation” (land sparing) approach. In this study, we evaluated the effects of land-use management on a guild of large carnivores in a montane ecosystem located in northeastern Iran. We used interview surveys to collect data on Persian leopard Panthera pardus saxicolor and grey wolf Canis lupus and modeled the areas occupied by these species in a Bayesian framework. After accounting for imperfect detection, we found that wolves had a higher probability of occupying the study area than leopards (82%; 95% CI 73–90% vs. 63%; 95% CI 53–73%). Importantly, each predator showed contrasting response to land-use management. National Parks (i.e. human-free areas) had a positive association with leopard occupancy (αNational Park?=?2.56, 95% CI 0.22–5.77), in contrast to wolves, which displayed a negative association with National Parks (αNational Park = ? 1.62, 95% CI ? 2.29 to 0.31). An opposite pattern was observed for human-dominated areas (i.e. Protected Areas and Communal Lands), where occupancy was higher for wolves but lower for leopards. Our study suggests that to protect these large carnivores, a combination of land sharing and land sparing approaches is desirable within Iran montane landscapes. Any recovery program for big cats in Iranian mountains, and likely similar mountainous landscapes in west Asia, should take into account other sympatric carnivores and how they can affect adjacent human communities. For example, conflict mitigation and compensation efforts are required to include the guild of large carnivores, instead of solely targeting the charismatic big cats.

  相似文献   

11.
Although spatial heterogeneity of prey and landscapes are known to contribute to variation around predator‐prey functional response models, few studies have quantified these effects. We illustrate a new approach using data from winter movement paths of GPS‐collared wolves in the Rocky Mountains of Canada and time‐to‐event models with competing risks for measuring the effect of prey and landscape characteristics on the time‐to‐kill, which is the reciprocal of attack rate (aN) in a Holling's functional response. We evaluated 13 a priori models representing hypothesized mechanisms influencing attack rates in a heterogeneous landscape with two prey types. Models ranged from variants on Holling's disc equation, including search rate and prey density, to a full model including prey density and patchiness, search rates, satiation, and landscape features, which were measured along the wolf's movement path. Movement rates of wolves while searching explained more of the variation in time‐to‐kill than prey densities. Wolves did not compensate for low prey density by increasing movement rates and there was little evidence that spatial aggregation of prey influenced attack rates in this multi‐prey system. The top model for predicting time‐to‐kill included only search rate and landscape features. Wolves killed prey more quickly in flat terrain, likely due to increased vulnerability from accumulated snow, whereas attack rates were lower when wolves hunted near human‐made features presumably due to human disturbance. Understanding the sources of variation in attack rates provides refinements to functional response models that can lead to more effective predator–prey management in human‐dominated landscapes.  相似文献   

12.
Quantifying how human-modified landscapes shape the distribution of biodiversity is critical for developing effective conservation strategies. To address this, we evaluated three hypotheses (habitat area, habitat configuration and matrix heterogeneity hypotheses) that predict responses of biodiversity to landscape structure in human-modified landscapes. We compared characteristics of landscape structure that influence taxonomic (TD), functional (FD), and phylogenetic (PD) dimensions of biodiversity of breeding birds in temperate forests. Relationships between biodiversity and landscape structure were assessed at multiple spatial scales for 20 forest interior sites in northeastern USA. We assessed if relationships with landscape structure were consistent among dimensions and assemblages of different groups (residents, migrants and all birds). Relationships between dimensions of biodiversity and landscape structure were more prevalent for FD and PD than for TD. Forest amount and configuration were rarely associated with any dimensions of biodiversity. In contrast, the identity of the matrix and heterogeneity of the landscape were frequently associated with biodiversity, but relationships differed among groups of birds. For example, FD of all birds was associated positively with landscape diversity but FD of residents was associated negatively with landscape diversity, suggesting that landscape diversity surrounding forests may increase overall FD of birds but that not all groups of species respond similarly. Indeed, biodiversity of migrants was only weakly related to landscape structure. Differences among relationships to landscape structure for bird groups and spatial scales suggests that management plans should consider local decisions within a regional framework to balance potentially conflicting needs of species groups in human-dominated landscapes.  相似文献   

13.
ABSTRACT Increasing demand for backcountry recreation opportunities during winter (e.g., snowshoeing, helicopter-assisted skiing, snowmobiling) in steep, high-elevation terrain has elevated concern about disturbance to brown bears (Ursus arctos) denning on the Kenai Peninsula, Alaska, USA. To help identify areas where such conflicts might occur, we developed a spatially explicit model to predict potential den habitat. The model indicated brown bears selected locations for den sites with steep slopes, away from roads and trails. Den sites were associated with habitat high in elevation and away from potential human contact. We then compared areas with the highest probability of providing den habitat with patterns of snowmobile and nonmotorized recreation on a portion of the Kenai Peninsula. We found limited overlap between the 2 recreation activities and potential den habitat for brown bears. At the landscape scale, however, backcountry skiing overlapped more high-quality den habitat than did snowmobile riding. Our results may be used by land management agencies to identify potential conflict sites and to minimize the potential effects of recreation activities on brown bears in dens.  相似文献   

14.
We conducted a 15-year study (1999–2014) of wolf denning behavior in Naliboki Forest, Belarus, to determine the extent to which some external factors (rain, mosquitoes, human disturbances) and litter size are negatively correlated with pup survival until autumn.For this purpose we entirely documented denning areas of 30 breeding wolf pairs. Initial denning area includes the natal den site and (ii) secondary den sites between which the parent wolves transported sucessively the litter during the rearing season.The number of den sites per denning area ranged from 1 to 4. The distances in kilometres differed significantly between den sites. The total number of dens (surface dens and burrows) was higher in the natal den site compared with the other den sites. The number of surface dens per den site was higher compared with burrows in den sites 1, 2 and 3 but not den site 4. A total of 168 pups was found over the 15 years. Litter sizes ranged from 1 to 11 (average 5.6 ± 1.9). The rate of pup survival ranged from 0 to 100% and averaged 54.5 ± 29%.We examined the bivariate association between environmental conditions (mosquitoes, rainfall and human presence) and number of surface dens, total number of burrows and number of den sites. Environmental conditions were assessed from spring to mid-summer. Results show that there was a positive relationship between environmental conditions and number of den sites, and also that more difficult environmental conditions (rainy weather, many mosquitoes) decreased pup survival both in absolute and in relative terms. A cluster analysis showed that pup survival was also influenced by human presence. Wolves probably have a more complicated denning behaviour following stressful event which may lead to less effectiveness for feeding or protecting pups. The number of pups surviving was also found to be lower when there were many (8–10) pups because den shifting is more risky in this case. Burrows improve pup survival. Our results tend to suggest that, in our study area, a high mortality rate of wolf pups could be related to external and internal factors of stress.  相似文献   

15.
车前进  曹有挥  于露  宋正娜  董雅文 《生态学报》2011,31(23):7261-7270
空间异质性是揭示地理现象空间分异规律的重要标志.基于高分辨率卫星遥感影像数据,利用景观生态指数和统计学方法,构建景观空间异质性综合模型,定量测度了江苏省沿江地区景观空间异质性特征及城市化关联,并基于二者的相关性将研究区域划分为6个异质性梯度区,提出了应对城市化干扰的景观空间协调对策.结果表明:景观空间异质性综合模型是对景观斑块结构、形态、数量3个组分特征的反映,是揭示景观连通性、稳定性和破碎化的重要依据;景观空间异质性与3个城市化参数之间存在显著的正相关,城镇空间扩张模式和城镇人口的集聚强度对景观空间异质性影响较大;景观空间异质性梯度分异与区域开发强度、开发时序存在显著的耦合关系;同时,面对城市化的干扰,应该实施保护生态景观空间、减少建设空间与其它景观的接触概率和实施差别化的城市化战略等政策协调城市化发展与景观生态保护之间的矛盾.  相似文献   

16.
Aim Factors acting at various scales may affect biodiversity, demanding analyses at multiple spatial scales in order to understand how community richness is determined. Here, we adopted a hierarchical approach to test the contribution of region, landscape heterogeneity, local management (organic vs. conventional) and location within field (edge vs. centre) to the species richness and abundance of spiders in cereals. Location Three regions of western and central Germany: Leine Bergland, Soester Boerde, and Lahn‐Dill Bergland. Methods Forty‐two paired organic and conventional winter wheat fields were compared. Field pairs were located in areas ranging from structurally simple to structurally complex landscapes. In May and June 2003, spiders were sampled using pitfall traps. Linear mixed models were used to determine the relationship of spider diversity and abundance with regional spatial factors and landscape heterogeneity within a 500‐m radius, as well as with local management and within‐field location. Results Within‐field location of the traps and landscape heterogeneity were the best predictors of species richness: more species were found in field edges and in heterogeneous landscapes. Region and local management had no effect on species richness. Activity density was higher in field edges and differed among regions. Main conclusions The diversity of farmland spiders was influenced by differences at two of the spatial scales (edge vs. centre, simple vs. complex landscapes), but not at the two others (field management, region), emphasizing the importance of analyses at a variety of spatial scales for an adequate explanation of patterns in biodiversity. Our study suggests that promoting heterogeneity in land use at landscape scales is one of the keys to promoting spider diversity in agroecosystems.  相似文献   

17.
Den sites are critical resources that ultimately influence the population dynamics of many species. Little is known about cougar den selection, even though dens likely play important roles in cougar fitness and kitten survivorship. Thus, we aimed to describe cougar den site selection in the Southern Yellowstone Ecosystem (SYE) at two scales (third- and fourth-order resource selection) and within an ecological framework that included environmental characteristics, as well as some measure of prey availability and anthropogenic landscape features. We documented 25 unique dens between 2002 and 2013, and gathered data on microsite characteristics and paired random points for 20 dens. The timing of dens was clumped in summer, with 56 % of 25 dens beginning in June or July. Unexpectedly, female cougars in our study system exhibited third-order selection for den areas in less rugged terrain, but did not exhibit selection for greater or lesser access to hunting opportunity, roads, water, or specific habitat classes, as compared with the remainder of their home ranges. Instead, our findings suggested that third-order selection for den areas was much less important than fourth-order selection: cougar den sites were characterized by high concealment and substantial protective structure. Therefore, our results provided evidence in support of land practices that promote and protect downed wood and heavy structure on forest floors—these will best provide opportunities for cougars to find suitable den sites and maintain parturition behaviors.  相似文献   

18.
Biodiversity in agricultural landscapes can be increased with conversion of some production lands into 'more-natural'- unmanaged or extensively managed - lands. However, it remains unknown to what extent biodiversity can be enhanced by altering landscape pattern without reducing agricultural production. We propose a framework for this problem, considering separately compositional heterogeneity (the number and proportions of different cover types) and configurational heterogeneity (the spatial arrangement of cover types). Cover type classification and mapping is based on species requirements, such as feeding and nesting, resulting in measures of 'functional landscape heterogeneity'. We then identify three important questions: does biodiversity increase with (1) increasing heterogeneity of the more-natural areas, (2) increasing compositional heterogeneity of production cover types and (3) increasing configurational heterogeneity of production cover types? We discuss approaches for addressing these questions. Such studies should have high priority because biodiversity protection globally depends increasingly on maintaining biodiversity in human-dominated landscapes.  相似文献   

19.
Understanding factors that affect the persistence of charismatic megafauna in human‐dominated landscapes is crucial to inform conservation decision‐making and reduce human‐wildlife conflict. We assessed the effect of environmental and anthropogenic factors at different landscape and management scales in predicting the distribution of African elephant (Loxodonta africana) within the Greater Mapungubwe Transfrontier Conservation Area in Southern Africa. We combined aerial distribution counts over a 12‐yr period with 14 variables, representing food availability, landscape, and anthropogenic effects, into generalized linear models. Generalized linear models were run for the broader landscape, as well as three separate management units within the broader landscape, namely ecotourism, trophy hunting, and a combination of hunting and ecotourism. Human activities within different management units forced elephant to trade‐off between disturbance avoidance, and good food and water availability. In addition, the important predictors of elephant distribution within each of the management units differed from the predictors at the broader landscape. Overall, our results suggest that at the fine scale, elephant are constraint by factors that may be masked at the broader landscape scale. We suggest that accounting for anthropogenic disturbance is important in determining the distribution of large, wide‐ranging, mammal species in increasingly human‐dominated landscapes, and that modeling needs to be done at the spatial scales at which conservation decisions are made.  相似文献   

20.
The spatial pattern of fire observed across boreal landscapes is the outcome of complex interactions among components of the fire environment. We investigated how the naturally occurring patterns of ignitions, fuels, and weather generate spatial pattern of burn probability (BP) in a large and highly fire-prone boreal landscape of western Canada, Wood Buffalo National Park. This was achieved by producing a high-resolution map of BP using a fire simulation model that models the ignition and spread of individual fires for the current state of the study landscape (that is, the ‘control’). Then, to extract the effect of the variability in ignitions, fuels, and weather on spatial BP patterns, we subtracted the control BP map to those produced by “homogenizing” a single environmental factor of interest (that is, the ‘experimental treatments’). This yielded maps of spatial residuals that represent the spatial BP patterns for which the heterogeneity of each factor of interest is responsible. Residuals were analyzed within a structural equation modeling framework. The results showed unequal contributions of fuels (67.4%), weather (29.2%), and ignitions (3.4%) to spatial BP patterning. The large contribution of fuels reflects how substantial heterogeneity of land cover on this landscape strongly affects BP. Although weather has a chiefly temporal control on fire regimes, the variability in fire-conducive weather conditions exerted a surprisingly large influence on spatial BP patterns. The almost negligible effect of spatial ignition patterns was surprising but explainable in the context of this area’s fire regime. Similar contributions of fuels, weather, and ignitions could be expected in other parts of the boreal forest that lack a strong anthropogenic imprint, but are likely to be altered in human-dominated fire regimes.  相似文献   

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