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1.
Predictions of climate change suggest major changes in temperature, rainfall as well as in frequency and timing of extreme weather, all in varying degrees and patterns around the world. Although the details of these patterns changes are still uncertain, we can be sure of profound effects on ecological processes in and functioning of landscapes. The impact of climate change will affect all types of land use, ecosystem services, as well as the behavior of humans. The core business of Landscape Ecology is the interaction of landscape patterns and processes. Most of these interactions will be affected by changing climate patterns, so clearly within the focus of our science. Nevertheless, climate change received little attention from landscape ecologists. Are we missing the boat? Why is it that our science does not contribute to building a knowledge base to help solving this immense problem? Why is there so little attention paid to adaptation of landscape to climate change? With this editorial article IALE would like to receive inputs from the Landscape Ecology scientific community in related research on adaptation of landscapes to climate change, on tools or approaches to help landscape planners and stakeholders to this new challenge where landscape ecology can play a key role.  相似文献   

2.
Long term studies have shown strong links between vegetation clearing and rainfall declines and more intense droughts. Many agroecosystems are exposed to more extreme weather and further declines in rainfall under climate change unless adaptations increase the retention of water in landscapes, and its recycling back to the lower atmosphere. Vegetation systems provide vital feedbacks to mechanisms that underpin water vapour recycling between micro- and meso-scales. Various heterogeneous forms of vegetation can help generate atmospheric conditions conducive to precipitation, and therefore, increase the resilience of agroecosystems to drought and climatic extremes. The aim of this paper is to demonstrate how vegetation can be designed for agroecosystems to enhance recycling of water vapour to the atmosphere through the regulation of surface water and wind, and heat fluxes. The structure of the paper revolves around five functions of integrated vegetation designs that can help underpin the restoration of water recycling through enhanced retention of stormwater, protection from wind, moistening and cooling the landscape, production of plant litter, and contribution toward regional scale climate and catchment functioning. We also present two supplementary functions relevant to land and natural resource managers which may also be integrated using these designs.  相似文献   

3.
Landscape ecology focuses on the spatial patterns and processes of ecological and human interactions. These patterns and processes are being altered by both changing resource-management practices of humans and changing climate conditions associated, in part, with increases in atmospheric concentrations of greenhouse gases. Dominant resource-extraction and land-management activities involve energy, and the use of fossil energy is one of the key drivers behind increasing greenhouse gas emissions as well as land-use changes. Alternative energy sources (such as wind, solar, nuclear, and bioenergy) are being explored to reduce greenhouse gas emission rates. Yet, energy production, including alternative-energy options, can have a wide range of effects on land productivity, surface cover, albedo, and other factors that affect carbon, water, and energy fluxes and, in turn, climate. Meanwhile, climate influences the potential output, relative efficiencies, and sustainability of alternative energy sources. Thus, land use, climate change, and energy choices are linked, and any comprehensive analysis in landscape ecology that considers one of these factors should be cognizant of these interactions. This analysis explores the implications of linkages between land use, climate hange, and energy and points out ecological patterns and processes that may be affected by their interactions.  相似文献   

4.
Larsen  Ashley E.  McComb  Sofie 《Landscape Ecology》2021,36(1):159-177
Context

Global environmental change is expected to dramatically affect agricultural crop production through a myriad of pathways. One important and thus far poorly understood impact is the effect of land cover and climate change on agricultural insect pests and insecticides.

Objectives

Here we address the following three questions: (1) how do landscape complexity and weather influence present-day insecticide use, (2) how will changing landscape characteristics and changing climate influence future insecticide use, and how do these effects manifest for different climate and land cover projections? and (3) what are the most important drivers of changing insecticide use?

Methods

We use panel models applied to county-level agriculture, land cover, and weather data in the US to understand how landscape composition and configuration, weather, and farm characteristics impact present-day insecticide use. We then leverage forecasted changes in land cover and climate under different future scenarios to predict insecticide use in 2050.

Results

We find different future scenarios—through modifications in both landscape and climate conditions—increase the amount of area treated by ~ 4–20% relative to 2017, with regionally heterogeneous impacts. Of note, we report large farms are more influential than large crop patches and increased winter minimum temperature is more influential than increased summer maximum temperature. However, our results suggest the most important determinants of future insecticide use are crop composition and farm size, variables for which future forecasts are sparse.

Conclusions

Both landscape and climate change are expected to increase future insecticide use. Yet, crop composition and farm size are highly influential, data-poor variables. Better understanding of future crop composition and farm economics is necessary to effectively predict and mitigate increases in pesticide use.

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5.
Landscape structure, or the spatial organization of different land units, has an impact on erosion and sedimentation on agricultural land. However, current erosion models emphasize the temporal, and less the spatial, variability of relevant parameters so that the effects of changes in landscape structure have hitherto not been studied in detail. Therefore, a spatially distributed water and tillage erosion model that allows the incorporation of landscape structure is presented. The model is applied to three study sites in the Belgian Loam Belt where significant changes in landscape structure occurred over the last fifty years. Erosion rates were shown to change by up to 28% however, with decreases as well as increases occurring. These could be explained by the interaction of changes in land use with changes in the position of field boundaries. Thus, landscape structure is an important control when the effect of environmental change on erosion risk is to be assessed.  相似文献   

6.
Oba  Gufu  Post  Eric  Syvertsen  P.O.  Stenseth  N.C. 《Landscape Ecology》2000,15(6):535-546
Progressive growth of bush cover in dry savannahs is responsible for declines in range conditions. In southern Ethiopia, the Booran pastoralists assisted our understanding of spatial patterns of bush cover and range conditions in 54 landscape patch types grouped into six landscape units within an area of 30000 km2. The size of landscape patches sampled was 625 m2. We assessed the relationships between bush cover, grass cover and bare soil and grazing pressure and soil erosion and changes in range condition. Externally, political conflicts and internally, break down of land use, and official bans on the use of fire promoted bush cover and the decline in range conditions. Bush cover was negatively correlated with grass cover, and positively correlated with bare soil. Grass cover was negatively correlated with bare soil and grazing pressure in most landscape patch types. Grazing pressure was not significantly correlated with bush cover or bare soil, while soil erosion was directly related to bare soil. Soil erosion was absent in 64% of the landscape patch types, and seemingly not a threat to the rangelands. The relationship between bush cover, grass cover, bare soil and soil erosion is complex and related to climate, landscape geology, and patterns of land use. Main threats to range conditions are bush climax, loss of grass cover and unpalatable forbs. Currently, >70% of the landscape patch types are in poor to fair range conditions. Decline in range conditions, unless reversed, will jeopardise the pastoral production system in southern Ethiopia.  相似文献   

7.
We focused on patterns of land use in a particular satoyama landscape (Japanese traditional rural landscape, comprised of an integral social and ecological network of a village and its surroundings, such as agricultural lands, open forestlands and forests), and the effects of human activities upon them during Japan’s economic growth of the last few decades. Changes of landscape patterns and their probable causes were traced since the beginning of the 1900s to the present, and clarified. Societal, economic and technological changes, especially those that occurred after 1970, were considered the focal points from which major landscape changes developed. We compared the spatial features, patterns of land use and landscape diversities of each land unit, defined in terms of both their natural and man-made conditions for the year 1970, to those of 1995. We found land-use diversity to be strongly related to changes in the patterns of land use, with a decrease in diversity for all land units after 1970. Diversity of forest-age distribution on the other hand, increased. These changes, with the complex, changing patterns of each land unit, could be explained by differences in accessibility from the village and variations in the topography, as well as land ownership of the land units. We selected those land units found to have responded to these factors between 1970 and 1995, and classified them into four types of pattern changes, determined mainly by accessibility and topography.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   

8.
Interest in the climate and an awareness of the beneficial cooling influence exerted on it by biologically-vital areas is growing, as climate change progresses, hot weather is more frequent as well as the urban heat island more intense. It is necessary to protect existing greenery in the cities and to introduce new planting. However plants in a warmer climate can produce larger amounts of pollen and are more readily able to initiate an allergic reaction among those prone to them. That means—not every greenery is advantageous for humans in the cities. In the research two housing estates built at different times and differ in type, density and age of buildings, as well as in the composition and the percentage of biologically vital area and the species planted were examined. Detailed inventory of tall greenery entailed the trees and shrubs and next their assumed allergenic potential was made. Cooling effect likely is derived from the difference in greenery, but the other factors such as differences in the density of buildings and spatial organization of the estate could also influence it. The older estate with the ratio of biologically vital areas of 54.3% is characterised by more favourable local climate than the newer estate, with the ratio of biologically vital areas equals 40.7% and young vegetation. On the newer one the perceptible thermal conditions did not differ significantly compared with the city centre. Unfortunately, on Koło Estate trees creating mild thermal conditions are also the trees promoting allergies most severely: birches, poplars and limes. And they are planted usually around playgrounds and kindergarten. The trees of high allergenicity should be partially removed, even risking small worsening thermal conditions.  相似文献   

9.
Much of the boreal forest in western North America and Alaska experiences frequent, stand-replacing wildfires. Secondary succession after fire initiates most forest stands and variations in fire characteristics can have strong effects on pathways of succession. Variations in surface fire severity that influence whether regenerating forests are dominated by coniferous or deciduous species can feedback to influence future fire behaviour because of differences in forest flammability. We used a landscape model of fire and forest dynamics to explore the effects of different scenarios of surface fire severity on subsequent forest succession and potential fire activity in interior Alaska. Model simulations indicated that high levels of surface fire severity leading to a prolonged phase of deciduous forest dominance caused a reduction in landscape flammability and fewer large fire events. Under low surface fire severity, larger patches of contiguous conifer forest promoted fire spread and resulted in landscapes with shorter fire return intervals compared to scenarios of high surface severity. Nevertheless, these negative feedbacks between fire severity, deciduous forest cover, and landscape flammability were unable to fully compensate for greater fire activity under scenarios of severe climate warming. Model simulations suggest that the effects of climate warming on fire activity in Alaska’s boreal forests may be partially but not completely mitigated by changes in fire severity that alter landscape patterns of forest composition and subsequent fire behaviour.  相似文献   

10.
Urban greening has rapidly emerged as a key urban climate change adaptation strategy. Urban greening is thought to confer manifold socio-ecological benefits upon residents in towns and cities. Yet proponents of urban greening have seldom considered how people’s support for greening policies may be shaped by weather and climate. This paper reports the results of exploratory research examining public expectations of adverse weather changes and people’s attitudes toward the functional benefits of urban trees and green space. Results of a questionnaire survey of 800 residents of Hong Kong indicate a positive relationship. Respondents tended to rate functional benefits as more important if they anticipated adverse weather changes in the near future, namely, rising temperatures, more tropical cyclones and prolonged rain. This subjective weather effect is more salient when these weather changes are perceived as a threat to one’s daily life. We found urban greenery is assigned a higher value by individuals concerned about exposure and vulnerability to climatic stressors. Affinity for greening appears to be related to how weather and climatic variability is perceived. This observation is informed by a broader geographic perspective, which construes weather and climate as part of the spatial environment in which urban nature is apprehended and comprehended. An explanation for our findings is that increasingly volatile weather can potentially reshape urban residents’ interactions with nature, based on perceived relief and/or protection from climate-related threats.  相似文献   

11.
The declines of many specialist bird species in the agricultural landscapes of Central Europe have resulted in small and isolated populations. In the case of the black grouse, a ground-nesting bird species with large spatial requirements, empiric evidence about underlying landscape changes is scarce. In this study, we examined land cover and land cover changes in a farmland-forest mosaic in eastern Lower Saxony, Germany and how they affect occurrence and persistence of black grouse. Spatial information came from historic topographic maps from 1958 to 1975. The results show profound conversions of habitat to forest and farmland but also an increase in settlement area. Habitat conversions and suburbanization were negative correlates of black grouse persistence. Habitat models from before and after a decline period differed in some of the predictors and suggest black grouse habitat to be more diverse before the land cover changes. Our study confirms that land use factors at a landscape scale extent contribute to explain black grouse occurrence and thus can complement important small scale factors like the quality and size of individual habitat patches. Results also show that landscape factors affect black grouse distribution predominantly from an area much greater than an individual black grouse home range. Our models may be further evaluated on present-day landscapes and might be used to evaluate large-scale habitat availability for black grouse.  相似文献   

12.
Human settlement is a formidable agent of change affecting fundamental ecological processes. Decisions governing these land-use changes occur almost exclusively at the local level and, as a result, they are made at many different locations and times. Consequently, it is difficult for ecologists to provide needed scientific support for these choices. We built an information system designed to support conservation decisions at local scales by offering data over the Internet. We collaborated with local stakeholders (e.g., developers, planners, politicians, land owners, environmental activists) to design the system. This collaboration produced several generalizations about effective design of information systems to support conservation. The most important of these is the idea that ecological data and analysis must be understood by those who will be affected by the decisions. Also, planning for conservation is a process that uses scientific data, but that ultimately depends on the expression of human values. A major challenge landscape ecologists face is to extend general landscape principles to provide specific scientific information needed for local land-use planning.  相似文献   

13.
We need an integrated assessment of the bioenergy production at landscape scale for at least three main reasons: (1) it is predictable that we will soon have landscapes dedicated to bioenergy productions; (2) a number of “win–win” solutions combining several dedicated energy crops have been suggested for a better use of local climate, soil mosaic and production systems and (3) “well-to-wheels” analyses for the entire bioenergy production chain urge us to optimize the life cycle of bioenergies at large scales. In this context, we argue that the new generation of landscape models allows in silico experiments to estimate bioenergy distributions (in space and time) that are helpful for this integrated assessment of the bioenergy production. The main objective of this paper was to develop a detailed modeling methodology for this purpose. We aimed at illustrating and discussing the use of mechanistic models and their possible association to simulate future distributions of fuel biomass. We applied two separated landscape models dedicated to human-driven agricultural and climate-driven forested neighboring patches. These models were combined in the same theoretical (i.e. virtual) landscape for present as well as future scenarios by associating realistic agricultural production scenarios and B2-IPCC climate scenarios depending on the bioenergy type (crop or forest) concerned in each landscape patch. We then estimated esthetical impacts of our simulations by using 3D visualizations and a quantitative “depth” index to rank them. Results first showed that the transport cost at landscape scale was not correlated to the total biomass production, mainly due to landscape configuration constraints. Secondly, averaged index values of the four simulations were conditioned by agricultural practices, while temporal trends were conditioned by gradual climate changes. Thirdly, the most realistic simulated landscape combining intensive agricultural practices and climate change with atmospheric CO2 concentration increase corresponded to the lowest and unwanted bioenergy conversion inefficiency (the biomass production ratio over 100 years divided by the averaged transport cost) and to the most open landscape. Managing land use and land cover changes at landscape scale is probably one of the most powerful ways to mitigate negative (or magnify positive) effects of climate and human decisions on overall biomass productions.  相似文献   

14.
Landscape indices describing a Dutch landscape   总被引：56，自引：0，他引：56  
The data set of a human modified Dutch landscape was used to evaluate whether landscape pattern indices developed in the United States are fit to describe a Dutch landscape. The grid based data set contains the development of land use over the period 1845–1982. The indices were divided in two groups: pattern indices and change indices. In the first group the proportion of each land use type (P), patch number (N), mean patch size (A) and two indices of patch shape (S1 and S2) were tested; in the second group the rate of change (C) was tested.Not all indices considered in this case study are suitable for the Dutch landscape. The dominance index (D) seems not to be sensitive enough to respond in a clear way to changes in the landscape studied. Shape index seems to be a complicated index, particularly in a human modified landscape like the Dutch, where the shape of natural patches is fixed by their man-made neighbours. The trends observed in the two shape indices considered in this study are not satisfactory since each index considers another aspects of shape (either the interior-to-edge ratio or the complexity of the patch perimeter).None of the indices appears to give information on changes in the geographical position of the patches, which implies that nothing can be induced with respect to the real landscape dynamics.The indices have to be considered in combination to produce meaningful information. The combination of proportion of each land use (P) and the data of the transitions shows how the development in land use has been. Number of patches (N) together with the mean size of patches (A) gives a good indication of the pattern development.Further research is necessary to develop a useful method how to quantify the change in landscape pattern and to give an ecological meaning to the index value in relation to the process of changing pattern.  相似文献   

15.
Landscape dynamics in crown fire ecosystems   总被引：21，自引：3，他引：18  
Crown fires create broad-scale patterns in vegetation by producing a patch mosaic of stand age classes, but the spread and behavior of crown fires also may be constrained by spatial patterns in terrain and fuels across the landscape. In this review, we address the implications of landscape heterogeneity for crown fire behavior and the ecological effects of crown fires over large areas. We suggest that fine-scale mechanisms of fire spread can be extrapolated to make broad-scale predictions of landscape pattern by coupling the knowledge obtained from mechanistic and empirical fire behavior models with spatially-explicit probabilistic models of fire spread. Climatic conditions exert a dominant control over crown fire behavior and spread, but topographic and physiographic features in the landscape and the spatial arrangement and types of fuels have a strong influence on fire spread, especially when burning conditions (e.g., fuel moisture and wind) are not extreme. General trends in crown fire regimes and stand age class distributions can be observed across continental, latitudinal, and elevational gradients. Crown fires are more frequent in regions having more frequent and/or severe droughts, and younger stands tend to dominate these landscapes. Landscapes dominated by crown fires appear to be nonequilibrium systems. This nonequilibrium condition presents a significant challenge to land managers, particularly when the implications of potential changes in the global climate are considered. Potential changes in the global climate may alter not only the frequency of crown fires but also their severity. Crown fires rarely consume the entire forest, and the spatial heterogeneity of burn severity patterns creates a wide range of local effects and is likely to influence plant reestablishment as well as many other ecological processes. Increased knowledge of ecological processes at regional scales and the effects of landscape pattern on fire dynamics should provide insight into our understanding of the behavior and consequences of crown fires.  相似文献   

16.
Mediterranean regions are under increasing pressure from global climate changes. Many have experienced more frequent extreme weather events such as droughts and heatwaves, which have severe implications for the persistence of forest ecosystems. This study reports on a landscape-scale assessment investigating potential associated factors of crown dieback in dominant tree species following an extreme dry and hot year/summer of 2010/11 in the Northern Jarrah Forest of Western Australia. Analyses focussed on the influence of (i) geology, (ii) topography, (iii) climate, and (iv) fire history. The results showed that trees on specific soils were more likely to show canopy dieback. Generally, trees on rocky soils with low water holding capacity were found to be affected more frequently. Other explanatory factors identified that dieback occurred (i) on sites that were close to rock outcrops, (ii) in areas that received a slightly higher amount of annual rainfall compared to the surrounding landscape, (iii) on sites at high elevations and (vi) on steep slopes, and (v) in areas that were generally slightly warmer than their surroundings. These results expand our understanding of how landscape-scale factors contribute to the effects of an extreme drought and heating event in Mediterranean forest ecosystems, and give indications of where changes are likely to occur within the landscape in the future. The analogues with other Mediterranean climate regions make the results of this study transferable and a starting point for further investigations.  相似文献   

17.

Context

Management of wintering waterfowl in North America requires adaptability because constant landscape and environmental change challenges existing management strategies regarding waterfowl habitat use at large spatial scales. Migratory waterfowl including mallards (Anas platyrhynchos) use the lower Mississippi Alluvial Valley (MAV) for wintering habitat, making this an important area of emphasis for improving wetland conservation strategies, while enhancing the understanding of landscape-use patterns.

Objectives

We used aerial survey data collected in the Arkansas portion of the MAV (ARMAV) to explain the abundance and distribution of mallards in relation to variable landscape conditions.

Methods

We used two-stage, hierarchical spatio-temporal models with a random spatial effect to identify covariates related to changes in mallard abundance and distribution within and among years.

Results

We found distinct spatio-temporal patterns existed for mallard distributions across the ARMAV and these distributions are dependent on the surrounding landscape structure and changing environmental conditions. Models performing best indicated seasonal surface water extent, rice field, wetland and fallow (uncultivated) fields positively influenced mallard presence. Rice fields, surface water and weather were found to influence mallard abundance. Additionally, the results suggest weather and changing surface water affects mallard presence and abundance throughout the winter.

Conclusions

Using novel datasets to identify which environmental factors drive changes in regional wildlife distribution and abundance can improve management by providing managers additional information to manage land over landscapes spanning private and public lands. We suggest our analytical approach may be informative in other areas and for other wildlife species.
  相似文献   

18.
Understanding which environmental conditions are critical for species survival is a critical, ongoing question in ecology. These conditions can range from climate, at the broadest scale, through to elevation and other local landscape conditions, to fine scale landscape patterns of land cover and use. Remote sensing is an ideal technology to monitor and assess changes in these environmental conditions at a variety of spatial and temporal scales, with many studies focusing on the physiological state of vegetation derived from time series of satellite measurements. As vegetation occurs within specific climatic zones, over certain soil, terrain, and land cover types, it can be difficult to decipher the influence of the underlying role of climate, topography, soil, and land cover on the observed vegetation signal. In this article, we specifically addressed this problem by asking the question: what is the relative impact and importance of these different scales of environmental drivers on the temporal and spatial patterns observed on a habitat index derived from remotely sensed data? To find the solution, we utilized a SPOT VEGETATION-normalized difference vegetation index time series of Europe to create a remote-sensing-derived habitat index, which incorporates aspects of productivity, seasonality, and cover. We then compared the observed temporal and spatial variations in the index to a pan-Europe terrestrial classification system, which explicitly incorporates variations in climate, terrain, soil parent material, land cover, and use. Results indicated that the most accurate level of discrimination from the habitat index was at the broadest level of the hierarchy, climate, while the poorest degree of discrimination was associated with elevation. In terms of similarity on the index across time and space, we found that arable and forest cover classes were more similar across elevation and parent materials than across other land cover types within them. Analyzing the remote-sensing index, at multiple scales, provides significant insights into the drivers of satellite-derived greenness indices, as well as highlights the benefit and cautions associated with linking satellite-derived indirect indicators to species distribution modeling and biodiversity.  相似文献   

19.
The historical geography of the landscape of a lowland brook valley in the sandy Kempen area (eastern Brabant, Netherlands) shows the interaction of ecological processes and land use, and helps to understand processes in the present landscape. In this location the human influence, especially on the groundwater hydrology, played a major role in the development of the landscape. Levels and flow of different types of groundwater interacted with vegetation development and human interference, to produce landscape patterns. Four main stages have been identified. In the prehistoric period, a natural deciduous forest covered the higher grounds, ombrotrophic peat was formed in the valley, and groundwater was relatively deep. In the medieval stage man settled on the edge of the valley, cleared parts of the forest and dug part of the peat. Groundwater levels were raised, which increased the rate of groundwater discharge and increased the amount of associated lowland peat formation in the valley. This tendency continued in modern times, when the area was completely deforested. Groundwater levels increased further due to decreased evapotranspiration, which gave rise to the use of ponds for fish and for water mills. Finally, in the most recent period the groundwater level has been lowered by extensive artificial drainage, partly on a regional scale. It was concluded that evaluation of historical changes in the landscape help provide landscape planners with a sound idea of the nature of the landscape.  相似文献   

20.
Perceived land use patterns and landscape values   总被引：3，自引：0，他引：3  
Land use patterns and land form are important sources of information that contribute to the formation of landscape perceptions and values. This paper discusses three concepts of human-landscape relationships: the human as an agent of biological and physical impacts on the landscape; the human as a static receiver and processor of information from the landscape; and the human as an active participant in the landscape —thinking, feeling and acting — a transactional concept. A model of the transactional concept and of human perception and response is presented along with a conjectural example of human-landscape transactions. Three empirical research projects are presented to illustrate varying relationships between and among humans and landscapes. Variations in human experiences, needs and desires, personal utility functions for the use of the landscape, and socio-cultural contexts are suggested as mediating variables on perceived values and human responses. The importance of landscape values information to planning and management activities is discussed.  相似文献   

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