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Appropriate forest thinning measures can mitigate the conflicting relationship between past excessive afforestation and current increasing regional water deficiency in dryland ecosystems. However, since blind intervention in forest landscapes may incur additional economic costs and cause the loss of ecosystem services, forest thinning in drylands mostly exists in scientific discussions and is seldom implemented in reality. In this study, we propose an advanced technical route to predict the spatial arrangement of potential forest thinning locations under different policy scenarios. Taking Shanxi Province in China as a case study, we simulated eight policy scenarios for different stakeholders to assess the benefits and costs after forest thinning in the future. The results show that a water deficit of 533 million m3 exists in Shanxi Province that could potentially be mitigated by means of forest thinning. Under different policy scenarios, the thinned area ranged from 1142.91 to 1195.47 km2, which would result in an additional soil loss of 1.77–3.02 million m3/year and a loss of carbon sequestration of 3.15–3.24 million t/year. Considering both soil conservation and food security scenarios can help minimize the direct costs and loss of forest carbon sequestration capacity and maintain a sustainable landscape pattern. The method can be used as a decision support tool to identify the potential locations of forest thinning and resulting consequences under water scarcity conditions in drylands and to support stakeholders in making scientific adaptive forest landscape optimization decisions. [ABSTRACT FROM AUTHOR]

Regional habitat quality is an important reflection of ecosystem services and ecosystem health. Exploring the characteristics of habitat quality changes and revealing the vulnerability of regional ecosystems caused could provide reference for the improvement of ecological service functions and the protection of regional ecological environment. Based on remote sensing data of Shaanxi Province from 2000 to 2015, InVEST model and grid analysis were used to analyze the evolution characteristics of habitat quality and landscape pattern, and spatial autocorrelation was also used to analyze the spatial correlation and temporal evolution characteristics. The results showed: (1) Arable land, grassland, and forest land were the main landscape types in Shaanxi province, accounting for more than 94% of the total area, and the arable land and unused land showed a decreasing trend, while the grassland and forest land showed an increasing trend, and the proportion of construction land continued to increase with the rapid economic development from 2000 to 2015; (2) The spatial distribution characteristics of habitat quality was similar to land use cover change, which was "high in the southern and central forest areas, low in the northern sandy land and central urban agglomeration", and habitat quality value showed a steady increase, indicating that the habitat quality was getting better; (3) The landscape pattern index values of Guanzhong Plain urban agglomeration changed significantly, which tended to be fragmented, and the landscape types were more diverse and uniform; (4) There were obvious spatial correlation between habitat quality and landscape pattern, and the spatial differentiation of clustering was obvious, and the clustering effect of habitat quality and landscape pattern characteristics would weaken with the increase in urbanization degree. The analysis of the spatial association between habitat quality and landscape pattern could provide scientific support for ecological protection and landscape planning. [ABSTRACT FROM AUTHOR]

Watershed governance based on landscape pattern is a key research topic of watershed sustainable development, and the ecosystem services related to water resource management (WMESs) have become an important focus. The current research mainly focuses on the impact of land use type or landscape pattern on WMESs, while few studies focus on the relationship between WMESs and food production (FP), and the understanding of the impact of landscape pattern configuration on the water–food relationship is relatively limited. In this study, the West Liaohe River basin in China was selected as the research area. Based on the assessment of three WMESs (water yield, WY; soil loss by water, SW; and water purification, WP) and FP using models, we analyzed the influence mechanism of landscape pattern evolution on water–food relationship from 2000 to 2020. Then, the optimal allocation scheme of regional landscape patterns was discussed based on future land use scenario simulations. The results showed that the influence of landscape pattern evolution on the water–food relationship at the patch type level was higher than that at the landscape level, and the spatial configuration of landscape patterns can improve the water–food relationship. Promoting the intensive management of cropland and strengthening the construction of forest and grassland can improve the overall capacity of the WMESs and FP supply in the watershed. The study suggests that the natural development scenario, economic development scenario (EDS), and ecological protection scenario (EPS) should be implemented in counties A, B, and C, respectively. This indicates that counties with higher FP capacity are suitable for the EDS, while counties with lower FP capacity are suitable for the EPS, which will help maximize the benefits of FP and WMESs protection. The results of this study can provide a direct decision‐making basis for the maximization of ecological‐production benefits of the water–food relationship in watersheds and provide a scientific reference for land use policy regulation and ecological security protection of the watershed areas. [ABSTRACT FROM AUTHOR]

Analysing the dynamics of landscape connectivity is of great significance for biodiversity conservation, but the scientific expression of ecological processes and the depth of coupling landscape pattern and ecological process requires to be strengthened. Taking the grassland of Poyang Lake as a case, based on the integrated perspective of habitat and biology, and comprehensively considering the ecological process of water level change and species dispersal, this study firstly analysed the changes of functional connectivity of grassland with different water levels and dispersal distances by using the graph‐based connectivity indices. Then, landscape pattern indices were applied to analyse the dynamics of landscape pattern of grassland and further study the effects of landscape pattern on landscape functional connectivity. The results showed as follows: (1) From the perspective of habitat, the functional connectivity of grassland has progressively decreased with the increase of water level. From the perspective of ecology, the species dispersal distance had an absolutely positive impact on landscape functional connectivity. With the increase of dispersal distance, the functional connectivity of grassland increased significantly. (2) The dynamics of landscape pattern of grassland showed that with the increase of water level, the patch area shrank, the patch shape tended to be simple, the patch density decreased and the patch fragmentation aggravated. (3) The correlation results between landscape pattern and functional connectivity indicated that flux index (F) had a significant positive relationship with patch density (PD), edge density (ED), probability of connectivity (PC) had a strong significant positive relationship with largest patch index (LPI), COHESION and number of components (NC) had a negative relationship with LPI, ED, COHESION. This study provides theoretical guidance for the protection and management of grassland in Poyang Lake. [ABSTRACT FROM AUTHOR]

The landscape pattern of the Black‐necked Crane (Grus nigricollis) habitat in China changed at different spatial scales and long‐term periods due to natural factors and human activities, and habitat reduction and fragmentation threatened the survival of Black‐necked Cranes. The factors driving the habitat landscape pattern and individual population changes of Black‐necked Cranes remain to be studied. In this paper, based on remote sensing data of land use from 1980 to 2020, the changes in landscape pattern and fragmentation of the Black‐necked Crane habitat in China over 40 years were analyzed from two different spatial scales using the land cover transfer matrix and landscape index. The correlation between landscape and Black‐necked Crane individual population was analyzed. The most obvious observations were as follows: (1) Although transformation between landscapes occurred to varying degrees, the area of wetlands and arable land in the breeding and the wintering areas (net) increased significantly from 1980 to 2020. (2) Habitat fragmentation existed in the breeding and the wintering area and was more obvious in the wintering area. (3) The number of individuals of Black‐necked Cranes increased period by period, and habitat fragmentation did not inhibit their population growth. (4) The number of individuals of Black‐necked Crane was closely related to the wetland and arable land. The increasing area of wetlands and arable and the increasing landscape shape complexity all contributed to the growth of the individual population. The results also suggested that the number of individuals of Black‐necked Crane was not threatened by the expanding arable land in China, and they might benefit from arable landscapes. The conservation of Black‐necked Cranes should focus on the relationship between individual Black‐necked Cranes and arable landscapes, and the conservation of other waterbirds should also focus on the relationship between individual waterbirds and other landscapes. [ABSTRACT FROM AUTHOR]

Aim: Recent studies highlight the importance of linking landscape ecology and macroecology for a better understanding of broad‐scale biodiversity patterns. The "landscape context effect" denotes that species responses and biodiversity in a focal area are shaped by neighbouring landscape composition and structure outside the focal area. Here, we test whether the landscape context effect could be pronounced at macroecological scales. Location: Sub‐Saharan Africa and continental China. Time period: Late 20th to early 21st centuries. Taxa studied: Terrestrial mammals (≥2 kg). Methods: We calculated species richness on the basis of grid cells of 50 km × 50 km and 100 km × 100 km. We used ordinary least square and random forest models to examine the relationships between species richness within grid cells and landscape context (defined as composition and structure of the neighbouring landscape outside the grid cells, with distances of 10–400 km to the boundary of a given grid cell). We used variation partitioning to quantify the independent and shared explanatory power of the landscape context variables, grouping species by body size and diet. Results: Landscape context alone explained ≤20% of the variation in species richness, even when controlling for correlations with macroenvironmental variables (climate, productivity and topography) and correlations with landscape attributes within the grid cells. Importantly, the explanatory power of landscape context at the scales of 100–400 km ofen outweighed grid‐cell landscape attributes or macro‐environmental variables. The independent explanatory power of landscape context was lowest for small‐sized omnivores. Furthermore, we found higher independent explanatory power for large herbivores in sub‐Saharan Africa than in continental China. Main conclusions: Landscape context plays a substantial role in shaping local biodiversity patterns at regional and continental scales, with its strength varying with organism diet and movement needs and possibilities. These findings support that conservation efforts should include effective management of landscape structure, with attention to differing space requirements among organism groups. Our work also illustrates the scope for testing landscape ecological hypotheses at macroecological scales. [ABSTRACT FROM AUTHOR]

Hydraulic connectivity has great effects on water quality. Enclosure aquaculture can largely alter lake flow regime and thus deteriorate water quality. Understanding the dynamics and influencing factors of water quality in enclosure aquaculture lakes is of great significance to ecosystem restoration of degraded lakes. However, it remains challenging due to the lack of long time series data. In this study, the dynamics of water quality in aquaculture dominated lakes were captured through 210Pb and 137Cs dating based on sediment records. Meanwhile, the effects of landscape pattern within aquaculture lakes on water quality were revealed by long time series of remote sensing images. Results showed the 210Pb and 137Cs sediment dating could provide an effective way to obtain long‐term series of lake water quality data in the unmonitored area. The contents of lake sediment nutrients showed an upward trend from 1960 to 2018. The transformation of lakes from agriculture dominated to aquaculture dominated had increased sediment nutrients level. The long‐term changes of lake sediment nutrients could be well explained by the landscape pattern metrics within aquaculture lakes, with an average explain power of 87.6%. The configuration metrics at class level had the most contribution (73.6%) to the changes of lake sediment nutrients, followed by the composition metrics (48.8%) and the configuration metrics at landscape level (33.4%). This study can provide a promising method to understand water quality changes in lakes with no historical monitoring data available and is of great benefit to water quality management in aquaculture dominated lakes. Plain Language Summary: Understanding the dynamics and influencing factors of water quality in enclosure aquaculture lakes is of great significance to ecosystem restoration of degraded lakes. However, it remains challenging due to the lack of long time series data. In this study, the dynamics of water quality in aquaculture dominated lakes were captured through 210Pb and 137Cs dating based on sediment records. Meanwhile, the effects of landscape pattern within aquaculture lakes on water quality were revealed by long time series of remote sensing images. The key contribution of this study is to provide a novel way to investigate the long‐term changes and the associated influencing factors of water quality in enclosure aquaculture dominated lakes through sediment records and time series of remote sensing images. This study also demonstrated the configuration metrics at class level had the most contribution to the changes of lake sediment nutrients in enclosure aquaculture dominated lakes, followed by composition metrics and configuration metrics at landscape level. This provide us with valuable insights into which factors determine water quality in enclosure aquaculture dominated lakes. Key Points: Long‐term changes of water quality in enclosure aquaculture dominated lakes were captured by sediment recordThe transformation of the lakes from agriculture dominated to aquaculture dominated had increased sediment nutrients levelLandscape pattern metrics within the aquaculture lakes can well explain the long‐term changes of lake water quality [ABSTRACT FROM AUTHOR]

Periodic flooding in floodplain wetlands dominates the landscape pattern, creating rich and diverse habitats for waterbirds. However, most studies on floodplain wetland landscape are conducted at interannual scale, while few researches investigate the effect of short‐term changes of hydrological components, such as maximum continuous flooding day, average flooding depth, maximum continuous drought day, and distance from water body. This study developed an effective approach by integrating a two‐dimensional hydrodynamic model and a geographic detector model to investigate the single and interactive effects of short‐term hydrological components on the landscape pattern of waterbird habitat in floodplain wetlands. The developed approach was demonstrated in the Poyang Lake in Jiangxi province of China, an important conservation floodplain wetland in the Ramsar Convention. We found the short‐term hydrological components could impose a significant impact on the landscape pattern of waterbird habitat. Particularly, the interactive effects of multiple hydrological components were stronger than that of a single component, showing nonlinear enhancement. The developed approach could provide a viable way to study the ecological impacts of short‐term hydrological components on the landscape pattern of waterbird habitat in floodplain wetlands, thus offer scientific references for waterbird habitat management in floodplain wetlands. Key Points: The short‐term hydrological components were used to characterize the landscape pattern of waterbird habitats in floodplain wetlandThe maximum continuous flooding day at monthly scale could impose significant impacts on the landscape pattern of meadowThe interactive effects of multiple hydrological components were stronger than that of a single component [ABSTRACT FROM AUTHOR]

Research on surface water (SW) dynamics is important for understanding climate change and the impacts of human activities on water resources. This article assesses the extent and direction of SW changes in the Pearl River Delta (PRD). Landsat images were used to determine the area of SW based on the modified normalized difference water index (MNDWI); the center of gravity was used to map the shifting distribution of SW dynamics; and landscape indices and potential causes of the observed SW changes were explored. Although the PRD has experienced high‐intensity economic development for 30 years, the total SW areas in 1988, 1998, 2008, and 2018 were 2,608, 3,154, 3,521, and 3,613 km2, respectively. The center of gravity of SW was in Shunde, Foshan (FS), which exhibited a trend of westward expansion. Over time, the landscape pattern of SW in the PRD became increasingly fragmented, and its shape tended to be complex. The growth of fish ponds was the most obvious change, as illustrated by the increase in aquatic product production. These and other findings highlight the importance of patterns, structures, and policies in SW dynamic analyses. Wetland and agricultural policies will likely cause the maintenance or continued expansion of SW areas. [ABSTRACT FROM AUTHOR]

Plateau pika burrows are common feature of degraded grassland in the Qinghai–Tibet Plateau (QTP) and serve as an important indicator of pika activity and grassland degradation. However, the current understanding of the spatial pattern changes of pika burrows and their critical thresholds across a degradation gradient in alpine grassland is deficient. In this study, we investigated and quantified changes in the spatial pattern of plateau pika burrows under typical degraded alpine shrub meadows in the northeastern QTP using an unmanned aerial vehicle and landscape pattern metrics. The degradation of the alpine shrub meadow leads to a change in landscape pattern from a two‐layered structure of alpine shrub and alpine meadow to a mosaic of alpine meadow and bare soil, with plateau pika burrows scattered throughout. Moderate degradation is the tipping point for changes in surface landscape patterns, followed by the disappearance of alpine shrub, the retreat of alpine meadows and the encroachment of bare soil, and the increasing density and size of pika burrows. The area characteristics of alpine meadows have influenced changes in the spatial pattern of pika burrow, and maintaining its proportional area is a vital measure to control the threat of pika burrows to pastures. The results of this paper provide a methodological reference and guidance for the sustainable utilization of grassland on the QTP. [ABSTRACT FROM AUTHOR]

Landscape heterogeneity is a comprehensive reflection of spatial patch and gradient, which is an important feature of landscape pattern. The China land use/cover dataset (CLUD) with 1 km spatial resolution was used in this study to investigate the dynamic changes of land use/cover in the Yarlung Tsangpo River basin (YTRB) of China from 1980 to 2015 through the land use transition matrix and dynamic degrees. The semi‐variogram model of the study area was constructed at different scales to determine the landscape characteristic scale of the YTRB. The traditional landscape index method and moving window method were used to investigate the watershed landscape pattern at the class and landscape levels, respectively. The results showed that the overall change in land use over the YTRB was not significant during the period 1980–2015, whereas the relative change in each type of land use was significant. Permanent glacier‐snow significantly degraded by 22.72%, while built‐up areas increased by 106.38%. The degree of the landscape fragmentation and diversity gradually increased from upstream to downstream. The unused land has the highest degree of fragmentation, and the agglomeration degree of urban land patches increased. The result of land use dynamic degree indicated that natural factors were the main causes of changes in land use during the first sub‐period 1980–2000, while human activities were the major drivers of changes in land use during the second sub‐period 2000–2015. The results can provide important information on the impact of regional development and environmental governance policies on the changes in land use/cover and landscape in Tibet. [ABSTRACT FROM AUTHOR]

Influenced by human activities, the largest freshwater lake in China, Poyang Lake is suffering from landscape degradation and increased ecological risks. However, the specific landscape ecological risk in Poyang Lake region remains unknown. The impact of land use change on landscape pattern and ecological risk around Poyang Lake has not been revealed. In order to analyze the spatio‐temporal distribution characteristics of landscape ecological risk in Poyang Lake region, this study constructed a landscape ecological risk index model based on GIS, geostatistics, and landscape ecology theory. The results show that: (a) all land use types in Poyang Lake region had been changed during the period 2010–2018. While large tracts of farmland and woodland were converted into construction land, farmland and woodland have seen the largest decrease and construction land has increased greatly. (b) On the whole, the low and medium‐low landscape ecological risk area accounted for about 60% of the total area, while high and medium‐high risk area increased during 2010–2018. The landscape ecological risk has seen a downward trend with increased low and medium‐low ecological risk areas during 2010–2018. Spatially, ecological risk in the core waters of Poyang Lake was higher, while in the surrounding waters was lower. (c) The landscape ecological risk in Poyang Lake Region in each period shown positive spatial correlation and tended to be spatially agglomerative. The high‐high risk clusters were mainly located in the core waters of the Lake area, while the low‐low risk clusters were mainly located far away from the core waters, including county and city areas. (d) In 2018, farmland, woodland, grassland, and unutilized land were dominated by medium and medium low risk, the landscape ecological risk in the water area was the highest, and that of construction land was the lowest. The decrease rate of ERI in water areas was the largest, indicating that the change of water area contributed the most to the reduction of landscape ecological risk. During the process of ecological risk management in Poyang Lake Region, attention should be paid to the changes of the water area's structure and quality. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET), a key component of the hydrological cycle, affects the transport of water and energy in the soil–vegetation–atmosphere system. Thus, quantifying the driving forces of ET dynamics is important to ensure rational water resource utilization. Based on meteorological and satellite data, spatiotemporal dynamics of ET were detected using the Surface Energy Balance System (SEBS) model, and effects of climate variability and landscape pattern change on ET dynamics in an arid to semiarid landscape mosaic during the growing season (April‐October) from 2001 to 2015 in Xilingol League, China were evaluated. The results indicated that (a) a significant increase (P <.05) in ET was found in the north‐eastern Xilingol League, and a significant decrease (P <.05) in ET was confined to the southwest and (b) climate variability had significant effects on ET dynamics. All climatic factors showed a positive correlation relationship with ET dynamics, and mean temperature (Ta) was the most influential climatic factor on ET dynamics followed by relative humidity (Rh), wind speed (Ws), and precipitation (Pr), respectively. The influence of landscape pattern change on ET dynamics was mainly reflected in the increase of the normalized difference vegetation index (NDVI) promoting ET dynamics. Several other landscape pattern metrics also had important impacts on ET dynamics, which were mainly reflected in the positive effect of the aggregation index (AI) on ET dynamics and the negative effects of the largest patch index (LPI), edge density (ED), and percentage of landscape (PLAND) on ET dynamics. To promote effective water resource utilization, landscape managers should continue to moderately implement vegetation restoration projects such as the Grain for Green Project, orient with conversion of low‐quality cropland into grassland, and conserve large areas of grassland. Appropriate management measures for forests and cropland scattered in the landscape mosaic, based on local climate and soil properties, as well as socioeconomic goals, are also required. [ABSTRACT FROM AUTHOR]

Aim: The aim was to assess whether and to what extent the role of local landscape attributes in shaping macroscopic biodiversity patterns is sensitive to spatial and thematic resolutions of land cover data. Location: Sub‐Saharan Africa and continental China. Time period: Early 21st century. Taxa studied: Terrestrial mammals. Methods: We conducted spatial and thematic scaling analyses to generate land cover datasets of different spatial (0.3, 0.5, 1.0 and 9.0 km) and thematic (two, three and five classes) resolutions. We calculated landscape metrics based on the resulting land cover maps and examined the power of landscape metrics for explaining species richness patterns, using non‐spatial (OLS) and spatial (SAR) linear models and random forest (RF) models. We systematically assessed the resolution dependence of explanatory power for different geographical regions, different scaling approaches and different model types. We also compared the explanatory power of landscape attributes with that of macroclimate. Results: Collectively, local landscape attributes generally had strong explanatory power for species richness. For the African system, the largest explanatory power was c. 60% based on the OLS models and random forest models and c. 30% based on the non‐spatial components of the SAR models. For the Chinese system, the largest explanatory power was c. 35% based on the OLS models and c. 40% based on the SAR and random forest models. We observed a linear scaling relationship, which is robust to studied systems, scaling approaches and model types. In contrast, the scaling relationship varies substantially among single landscape metrics. At coarse resolutions, the addition of landscape attributes collectively would not improve climate‐envelope models significantly, whereas at finer resolutions, landscape attributes collectively have explanatory power that is close to or even exceeds climate. Main conclusions: Local landscape attributes play an important role in shaping macroscopic biodiversity patterns. However, their strength is highly sensitive to both spatial and thematic resolutions of land cover data, with stronger explanatory power detected at finer resolutions. Strong sensitivity to spatial and thematic resolutions makes landscape attributes highly plastic determinants, leading to contrasting conclusions if based on greatly different resolutions of land cover data. Scaling analyses are needed to examine such cross‐scale effects of macroecological determinants systematically. [ABSTRACT FROM AUTHOR]

Landscape composition is consequential to ecological functions, and in agricultural regions a simple descriptor of composition is whether the growing habit of vegetation is annual or perennial. Annual vegetation includes most of the crop species grown in central North America (e.g., corn, soybeans, cereal grains, canola), and perennial vegetation includes hay and forage crops (e.g., alfalfa) and most non‐crop land covers (e.g., woodlands, grasslands, wetlands). Recent data show that in farmlands perennial cover is converting to annual cover. Using new remotely sensed annual crop layer spatial data for an intensively farmed region (1,700 km2) of the Lake Huron watershed in Southern Ontario, Canada, this paper describes changes in farmland composition and which transitions are occurring, with suggestions for why the changes are occurring. Perennial cover has rapidly been converted to annual cover in the past five years, with working‐lands perennial cover types identified as the most vulnerable to conversion. Other land cover types are relatively static. Implications for agricultural land conservation and stewardship require attention to this rapid change for conservation of soil, water, and biodiversity in the Great Lakes basin. [ABSTRACT FROM AUTHOR]

Numerous studies have focused on the relationship between landscape structure and plant diversity based on the patch-mosaic landscape paradigm, by deriving structural data from classified images. Since the use of discrete classes poses limitations for predicting biodiversity patterns in complex, low human-impacted ecosystems, two alternative methods have been used to analyze changes of landscape attributes in a continuum: moving-window metrics and surface metrics (image texture). Here, we compare these two approaches for predicting richness of all plant species, legume species, legume trees, legume shrubs, legume forbs, and legume climbers across a tropical landscape in Mexico, based on the records of vascular plants in 250 10 x 10 m plots. Multiple regression and variance partitioning methods were used to analyze the effects of the two landscape descriptors (moving-window and surface metrics), scale (400- and 200-m moving-window sides), and space (based on the extraction of principal coordinates of neighbor matrices' vectors) on species richness. The predictive power of all metrics was relatively small for total species richness, but generally higher for legume species. For legume forbs, surface metrics-based models indicated a direct association between species richness and landscape homogeneity. Moving-window metrics were highly sensitive to the biological group and to spatial scale, likely due to a leftover effect of image classification procedures. Conversely, surface metrics were more independent from scale and taxonomy. Attempts to predict species richness in highly diverse, low human-impacted tropical ecosystems more rapidly and accurately should better rely on surface metrics rather than on moving-window metrics, in line with the continuous landscape paradigm. [ABSTRACT FROM AUTHOR]

Many factors affect the presence and exchange of individuals among subpopulations and influence not only the emergence, but the strength of ensuing source-sink dynamics within metapopulations. Yet their relative contributions remain largely unexplored. To help identify the characteristics of empirical systems that are likely to exhibit strong versus weak source-sink dynamics and inform their differential management, we compared the relative roles of influential factors in strengthening source-sink dynamics. In a series of controlled experiments within a spatially explicit individual-based model framework, we varied patch quality, patch size, the dispersion of high- and low-quality patches, population growth rates, dispersal distances, and environmental stochasticity in a factorial design. We then recorded source-sink dynamics that emerged from the simulated habitat and population factors. Long-term differences in births and deaths were quantified for sources and sinks in each system and used in a statistical model to rank the influences of key factors. Our results suggest that systems with species capable of rapid growth, occupying habitat patches with more disparate qualities, with interspersed higher- and lower-quality habitats, and that experience relatively stable environments (i.e., fewer negative perturbations) are more likely to exhibit strong source-sink dynamics. Strong source-sink dynamics emerged under diverse combinations of factors, suggesting that simple inferences of process from pattern will likely be inadequate to predict and assess the strength of source-sink dynamics. Our results also suggest that it may be more difficult to detect and accurately measure source-sink dynamics in slow-growing populations, highly variable environments, and where a subtle gradient of habitat quality exists. [ABSTRACT FROM AUTHOR]

The spread of invasive species is a global problem of major ecological and economic concern. Landscape level assessment of invasive spread is critical, but remote sensing ( RS) analyses are often complicated by the spectral similarity of species and the need to balance spatial resolution with data storage and analysis complexity. One example is the ridge and slough landscape ( RSL) of the Florida Everglades, where inflowing nutrients have facilitated large-scale cattail invasions. Hand delineation of aerial imagery has been successful in mapping cattail spread, but this technique requires considerable time and effort. Computerized classification of medium-resolution imagery would increase the ability of scientists to provide up-to-date data for water management decisions. Advances in RS technologies have created opportunities that were not previously available in landscapes such as the RSL-to automatically classify sawgrass and cattail communities with medium-resolution satellite imagery using knowledge of the invasion ecology of cattail and landscape context. We developed a computer-classification technique that provided measure of cattail expansion that matched ground-truthed data and show an increase in cattail area (similar to previous estimates), but a reduction in the rate of expansion over time. Although this technique can miss small patches of plants that might indicated new invasions, its rapid mapping can improve tracking of invasion fronts in the Everglades and other landscapes. [ABSTRACT FROM AUTHOR]

Water level changes at Poyang Lake have great impact of the area of the lakeshore wetlands and landscape spatial pattern. Therefore, the research of the structure, rules, and driving forces for changes of the wetlands have great reference value to the management of Poyang Lake basin. This article first introduce the research methods and date source, including the definition of lakeshore hydro-fluctuation belt, wetland classification method, interpretation method, and so on Based on remote sensing (RS) and geographic information system (GIS) tools, it analyzes the yearly change rules of landscape spatial pattern and the composition characteristics of lakeshore wetlands. We analyzes the changes in landscape spatial pattern by process the RS images under equivalent water level over a long period from 1985 to 2005, and the natural, social, economic and policy driving forces were also analyzed on a basis of social economic statistics. Results indicate that there is a significant change of spatial pattern in the lakeshore wetlands landscape under an equivalent water level and human activities are the main driving forces for the changes. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1129-1135, 2015 [ABSTRACT FROM AUTHOR]

The interaction between land use/cover change and landscape pattern is pivotal in research concerning global environmental change. This study uses three different Landsat images of 1989, 1998 and 2009 to study the land use/cover and landscape pattern changes in the middle reaches of the Tarim River basin. envi®, erdas®, ArcGIS® and fragstats® software were used to analyse the land use/cover changes. The objectives of study were to map and study the changes in land use/cover and landscape pattern, and propose some possible factors in making the land use/cover changes from 1989 to 2009. Seven different types of land use/cover are analysed, and the results are listed in tables. From 1989 to 1998, the percentage of farmland, slight-moderate saline land, heavy saline land and water areas have increased; woodland, desert and the undeveloped land have decreased. From 1998 to 2009, farmland, heavy saline land and the undeveloped land have increased; the other types of land use/cover have decreased. The gravity centre of each land use/cover types has shifted. The farthest shifting of the gravity centre was heavy saline land, which occurred between 1989 and 1998. The transformation and changes of land use/covers and landscape occurred more frequently from 1989 to 2009. Other types of land use and land cover changes to saline land have increased, which implied that a serious salinization took place in the Tarim Basin. The results from this study would show the adverse environmental changes (e.g. salinization and desertification) and they can be used for future sustainable management of land resources. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT We used multi-season occupancy analyses to model 2 fates of northern spotted owl territories in relation to habitat amount, habitat fragmentation, and the presence of barred owls in Washington State, USA, 1989-2005. Local colonization is the probability a territory unoccupied by a spotted owl in year i would be occupied in year i + 1, and local extinction is the probability a territory that was occupied by a spotted owl in year i would be unoccupied in year i + 1. We found a negative relationship between local extinction probability and amount of late-seral forest edge. We found a negative relationship between colonization probability and the number of late-seral forest patches (higher fragmentation), and a negative relationship between colonization probability and the amount of non-habitat within 600 m of a spotted owl territory center (Akaike weight = 0.59). The presence of barred owls was positively related to extinction probability and negatively related to detection probability of spotted owls. The negative relationship between presence of barred owls and detectability of spotted owls indicated that spotted owls could be modifying their calling behavior in the presence of barred owls. The positive relationship between barred owl detections and local extinction probability suggests that because of competition with barred owls, spotted owls are being displaced. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Despite the fact that pixels (i.e. picture elements) are the basic sampling units of maps, we are aware of no software package or tool that allows users to model changes that may occur at such fine spatial resolutions over broad geographic extents., Curve Fit is an extension to the application ArcMap that allows users to conduct linear or nonlinear regression analysis on the range of values found within input raster data sets (geo-referenced images), independently for each pixel., Outputs consist of raster surfaces of regression model parameter estimates, standard errors, goodness-of-fit estimates and multimodel inference measures., Curve fit outputs characterize continuous spatial or temporal change across a series of raster data sets. [ABSTRACT FROM AUTHOR]

Dry subtropical regions (DST), originally hosting woodlands and savannas, are subject to contrasting human pressures and land uses and different degrees of water limitation. We quantified how this variable context influences landscape pattern and vegetation functioning, by exploring the associations between three groups of variables describing (i) human pressures (population density, poverty, and market isolation) and climate (water availability), (ii) landscape pattern (woody cover, infrastructure, paddock size, etc.), and (iii) vegetation functioning (magnitude and stability of primary productivity), in regions of Asia, Africa, Australia, and America. We collected data from global socioeconomic databases and remote sensing products for 4525 samples (representing uncultivated and cultivated conditions), located along 35 transects spanning semiarid to subhumid conditions. A Reciprocal Averaging ordination of uncultivated samples revealed a dominant gradient of declining woody cover accompanied by lower and less stable productivity. This gradient, likely capturing increasing vegetation degradation, had a negative relationship with poverty (characterized by infant mortality) and with market isolation (measured by travel time to large cities). With partial overlaps, regions displayed an increasing degradation ranking from Africa to South America, to Australia, to North America, and to Asia. A similar analysis of cultivated samples, showed a dominant gradient of increasing paddock size accompanied by decreasing primary productivity stability, which included all regions except Asia. This gradient was negatively associated with poverty and population density. A unique combination of small paddocks and high infrastructure differentiated Asian cultivated samples. While water availability gradients were related to productivity trends, they were unrelated to landscape pattern. Our comparative approach suggests that, in DST, human pressures have an overwhelming role driving landscape patterns and one shared with water availability shaping vegetation functioning. [ABSTRACT FROM AUTHOR]

Questions How does the presence of understorey plant species vary with distance-to-edge along very large periphery-to-interior and forest patch size gradients? Can forest core and periphery species profiles be identified? What life-history traits can discriminate between forest core and forest periphery species? Location Temperate forests in the northern half of France. Methods Local climate, soil, stand characteristics and landscape metrics were collected on 19 989 plots in 1801 forest patches using data from the French National Forest Inventory. Very large distance-to-edge (3-1096 m) and patch size gradients (327-100 000 ha) were explored. Four logistic regression models were compared to determine the response patterns of 214 species to distance-to-edge, while controlling for patch size and local habitat quality (soil, climate and stand). The maximum distance of correlation between species occurrence and distance-to-edge was assessed using response curve characteristics. The relationships between life-history traits (habitat preference, preference for ancient forests, reproduction mode, dispersal mode, life form and autecology) and species profile according to distance-to-edge were tested. Results Of the 214 species analysed, 40 had a core profile and 38 a periphery profile. The maximum distance of correlation was on average 748 m. Core species were more often species reproducing both by seed and vegetatively, ancient forest species, anemochores, bryophytes, pteridophytes, hemicryptophytes and acidophiles, whereas peripheral species were more often species reproducing by seed only, endozoochores, phanerophytes, thermophiles, basophiles, nitrogen-demanding and heliophiles. Conclusions Significant periphery-to-core patterns of distribution were detected over much larger ranges than hitherto recognized for common understorey plant species. Plant traits differentiated forest core from forest periphery species. This deep gradient cannot be solely explained by the usual edge-related biotic and abiotic factors. We hypothesized that it was due to edge displacement following general reforestation since ca. 1830. This edge shift created recent forests with new habitats on former agricultural lands where dispersal-limited core species had slowly expanded and forest edge species regressed at variable speeds. This long periphery-to-interior gradient of presence has important implications for forest plant species distribution, dynamics and conservation. [ABSTRACT FROM AUTHOR]

Landscape and local-scale influences are important drivers of plant community structure. However, their relative contribution and the degree to which they interact remain unclear. We quantified the extent to which landscape structure, within-patch habitat and their confounding effects determine post-clearing tree densities and composition in agricultural landscapes in eastern subtropical Australia. Landscape structure (incorporating habitat fragmentation and loss) and within-patch (site) features were quantified for 60 remnant patches of Eucalyptus populnea (Myrtaceae) woodland. Tree density and species for three ecological maturity classes (regeneration, early maturity, late maturity) and local site features were assessed in one 100 × 10 m plot per patch. All but one landscape characteristic was determined within a 1.3-km radius of plots; Euclidean nearest neighbour distance was measured inside a 5-km radius. Variation in tree density and composition for each maturity class was partitioned into independent landscape, independent site and joint effects of landscape and site features using redundancy analysis. Independent site effects explained more variation in regeneration density and composition than pure landscape effects; significant predictors were the proportion of early and late maturity trees at a site, rainfall and the associated interaction. Conversely, landscape structure explained greater variation in early and late maturity tree density and composition than site predictors. Area of remnant native vegetation within a landscape and patch characteristics (area, shape, edge contrast) were significant predictors of early maturity tree density. However, 31% of the explained variation in early mature tree differences represented confounding influences of landscape and local variables. We suggest that within-patch characteristics are important in influencing semi-arid woodland tree regeneration. However, independent and confounding effects of landscape structure resulting from previous vegetation clearing may have exerted a greater historical influence on older cohorts and should be accounted for when examining woodland dynamics across a broader range of environments. [ABSTRACT FROM AUTHOR]

Portions of the south coast of Western Australia are recognized as environmentally valuable because of high levels of biodiversity, but are at risk due to continued anthropogenic influences, particularly in the form of fragmentation and habitat loss. Corridors of habitat, either continuous or stepping-stone, are deemed to be valuable for the maintenance and increase of biodiversity in the region. Here we apply a series of betweenness centrality analyses to quantify the connectivity in the region. The method we describe here is an extended application of the betweenness centrality measure, which is a measure of spatial connectivity that is applied to fragmented landscapes. The method is used for significant corridors between the Stirling Ranges and the Fitzgerald River National Park to identify a series of locations that are important to the connectivity in this region and thus may provide effective locations for restoration inputs. [ABSTRACT FROM AUTHOR]

Suburban, exurban, and rural development in the United States consumes nearly 1 million hectares of land per year and is a leading threat to biodiversity. In response to this threat, conservation development has been advanced as a way to combine land development and land conservation while providing functional protection for natural resources. Yet, although conservation development techniques have been in use for decades, there have been few critical evaluations of their conservation effectiveness. We addressed this deficiency by assessing the conservation outcomes of one type of conservation development project: conservation and limited development projects (CLDPs). Conducted by land trusts, landowners, and developers, CLDPs use revenue from limited development to finance the protection of land and natural resources. We compared a sample of 10 CLDPs from the eastern United States with their respective baseline scenarios (conventional development) and with a sample of conservation subdivisions—a different conservation development technique characterized by higher-density development. To measure conservation success, we created an evaluation method containing eight indicators that quantify project impacts to terrestrial and aquatic ecosystems at the site and in the surrounding landscape. The CLDPs protected and managed threatened natural resources including rare species and ecological communities. In terms of conservation benefits, the CLDPs significantly outperformed their respective baseline scenarios and the conservation subdivisions. These results imply that CLDPs can offer a low-impact alternative to conventional development and a low-cost method for protecting land when conventional conservation techniques are too expensive. In addition, our evaluation method demonstrates how planners and developers can incorporate appropriate ecological considerations when designing, reviewing, and evaluating conservation development projects. [ABSTRACT FROM AUTHOR]

1. Invasive species are present worldwide, yet predicting which invasive species will become problematic in which ecosystems remains an important ecological challenge. Floodplains are at particular risk for invasion, especially when subjected to anthropogenic disturbance. 2. We examined how components of flood regime, habitat quality and habitat configuration influenced the presence and abundance of three invasive shrubs in the floodplain of the Wisconsin River. Shrub taxa included two non-natives ( Lonicera spp. and Rhamnus spp.) and one native ( Zanthoxylum americanum). Observations of taxa presence and abundance were recorded in nine forested river reaches, spanning three physiographic regions. We also compared the productivity of Z. americanum across a flood control levee in one reach. 3. Physiographic region significantly predicted the presence and abundance of these three taxa, acting as a synthetic indicator of differences in climate, geography and topography. Invasion was greatest in regions where modifications to flood regime and land use were most pronounced. Physiographic region was excluded from subsequent analyses to assess more specific predictors of shrub distributions. 4. Habitat configuration and quality both predicted shrub taxa presence and abundance. Shrub taxa were most frequently observed and most abundant in small forest patches, near roads, and in sandy soil with low nutrient content. Edge habitats have many of these characteristics. Edges appear to be favoured by avian shrub dispersers and provide conditions suitable for invasive establishment. 5. Flooding influenced non-native and native invaders differently. Non-native taxa were observed less frequently and at lower abundances in frequently flooded areas, probably because of a sensitivity to flooding. However, the presence, abundance and productivity of the native invader increased with flooding. Anthropogenic modifications to the flood regime limited hydrologic connectivity and may have reduced the competitive advantage of flood-tolerant traits, which allowed the invasion of upland species. 6. Synthesis. In the floodplain of the Wisconsin River, anthropogenic modifications that created edge habitat and altered flood regime facilitated shrub invasions, whereas unfragmented forest and intact flood regime limited invasion. Large patches of floodplain forest, less regulated flooding regimes, and lower road densities may help reduce the spread of invasive shrubs in temperate floodplains. [ABSTRACT FROM AUTHOR]

Contents Summary Invasive nonindigenous plant species (NIPS) threaten native diversity, alter ecosystem processes, and may interact with other components of global environmental change. Here, a general framework is outlined that attempts to connect patterns of plant invasion to processes underlying these patterns at four well-established spatio-temporal stages of the invasion process: transport, colonization, establishment, and landscape spread. At each stage we organize findings and ideas about the filters that limit NIPS success and the interaction of these filters with historical aspects of introduction events, NIPS traits, and ecosystem properties. While it remains difficult to draw conclusions about the risk of invasion across ecosystems, to delineate universal ‘invader traits’, or to predict large-scale extinctions following invasions, this review highlights the growing body of research that suggests that the success of invasive NIPS is controlled by a series of key processes or filters. These filters are common to all invasion events, and will interact throughout the stages of plant invasion, although the relative importance of a filter may be stage, species or location specific. It is suggested that both research and management programs may benefit from employing multiscale and stage approaches to studying and controlling invasion. We further use the framework to briefly examine potential interactions between climate change and filters that limit NIPS invasion. [ABSTRACT FROM AUTHOR]

The article investigates the effects of road network dynamics to landscape patterns in northern Wisconsin, and identifies relationships between road changes and other land-use shifts. The researchers mapped roads from aerial photographs between 1937 and 1999 from 17 towns in a densely forested landscapes in the state. They used both patch-level landscape metrics in calculating terrestrial area outside 15-meter road-effect zone and generalized least-squares regression models in relating road density shifts and landscape pattern to concurrent housing density changes. Their findings revealed that road density increases attributed to landscape fragmentation. They stressed that recognizing road network dynamics is significant for forecasting their ecological impacts over time.

Aim In the transition between the southern Sudanian and northern Guinean zones of West Africa, numerous islands of predominantly semi-deciduous forests are interspersed in extensive savannas. During the past decades, human population and intensity of land use have increased. At the same time, almost nothing is known about the natural dynamics of this widespread forest–savanna mosaic and how they are altered by human activities. This was investigated with respect to past, present and future forest–savanna dynamics, which presumably influence northern Guinean biodiversity. Location The Comoé National Park (CNP) region in north-eastern Ivory Coast. Methods Landscape dynamics and the rates of anthropogenic deforestation and natural reforestation were retrospectively analysed by means of historical and recent aerial photographs and satellite images, directly relating the semi-natural conditions in the CNP to neighbouring, traditionally utilized countryside. Results From 1954 to 1996, the studied forest–savanna pattern proved to be remarkably stable, even with extensive land utilization outside the CNP. The contour towards the surrounding savanna and, thus, the size of 95.4% of 653 forest islands remained unchanged. Unvegetated surfaces also remained remarkably constant during the period from 1967 to 1996. Although dynamics were clearly higher outside the CNP as a result of human activities, the 913 unvegetated surfaces studied showed no general trend of decrease or increase, i.e. there was no response over the study period to an identified climatic shift. Anthropogenic deforestation and subsequent natural reforestation within the contours of the existing forest have occurred to a noteworthy extent only outside the CNP. For the period 1988–2002, the extent of deforestation was greater than the extent of reforestation (40% vs. 14%). By 2002, 62% of the original gallery forest along a 75-km section of the Comoé river had been cleared. Main conclusions With its remarkable overall stability, the landscape pattern inside the CNP has responded with resilience to varying influences (in particular climatic variations) and disturbances (e.g. episodic mass herbivory). A possible natural succession from savanna to forest appears to proceed only very slowly due to the counteracting effects of annual savanna fires and the lower climatic humidity of the area compared to the southern Guinean zone. Consequently, the forests should be considered as habitat islands rather than as habitat fragments. As deforestation outside the CNP has increased considerably, the pre-existing pattern of forest insularization is now becoming overlain in these non-CNP areas by a pattern of forest fragmentation. This will aggravate the ecological and genetic isolation of the undisturbed forests in the CNP, which are among the last remaining natural forests of the entire Guineo-Sudanian transition zone. [ABSTRACT FROM AUTHOR]

Seagrass beds are some of the most productive parts of coastal ecosystems, hosting a wide variety of associated fauna. This paper reviews recent studies of animal–plant interactions in seagrass beds, focusing particularly on studies conducted in Japan and Thailand. Although the positive effect of seagrass habitat structure on animals has been widely acknowledged, the magnitude of this effect varies greatly among studies. A comparative study on epifaunal communities and a manipulative experiment using an infaunal bivalve revealed that behavioral and life-history traits of component species and their interactions influence the observed variation. Some recent studies have challenged the previously accepted view that direct herbivory on seagrasses is rare, and has a minor effect on the seagrass community. A series of studies of dugong herbivory revealed that the marine mammal has great impacts not only on seagrass productivity but also on the infaunal community. Furthermore, it has been found that seed predators have a negative influence on seed production and the subsequent recruitment of seagrass. Recent studies have also demonstrated significant effects of fine-scale landscape patterns in seagrass vegetation on productivity, species interactions and community structure in seagrass beds. Future research integrating new concepts and theories in ecology, such as metapopulation and hierarchy theories, with new research tools, such as molecular-genetic analyses and remote-sensing techniques, may aid in developing a more comprehensive understanding of population and community dynamics in seagrass beds. [ABSTRACT FROM AUTHOR]

The issue of scaling impinges on every aspect of landscape ecology and much of ecology in general. Consequently, the topic has invited a vast commentary. One result of scaling research is so-called scaling laws that describe how observations scale (e.g., as power laws). Importantly, such scaling rules seldom derive from a process-based understanding of why they emerge. Alternatively, the task of scaling is often addressed via simulation models. This is a scaling operation about which we are somewhat less confident, although recent advances in computing power and computational statistics provide for some promising new solutions. Here, I focus on methods for scaling simulations developed at fine grain and small extent, to their implications over much larger extent. The intent in scaling is to simplify the model while retaining those details essential for larger-scale applications. This approach should lead to scaling rules that are well founded in fine-scale ecological process and yet useful for making predictions at the larger scales of management and environmental policy. [ABSTRACT FROM AUTHOR]

Metapopulation models assume that local population size (in a habitat patch) and therefore local extinction probability, is a function of patch size, and that interpatch movement rate and therefore recolonization of local extinctions is a function of both patch size and patch isolation. We hypothesized that the predictive power of models that relate patch immigration rate to patch size and isolation will be reduced when spatial structure in the landscape matrix (the nonhabitat portion of the landscape) affects organism movement through the landscape. We used a simulation model to evaluate this hypothesis for three different aspects of matrix spatial structure (contrast among matrix cover types, number of matrix cover types, and grain of matrix spatial pattern) and for two different types of movement behavior, representing a specialist and a generalist species. We tested the hypothesis for one aspect of matrix structure (number of matrix cover types) in a translocation field study of the eastern chipmunk (Tamias striatus, a habitat specialist) and the white- footed mouse (Peromyscus leucopus, a habitat generalist). When the matrix was composed of a small number of cover types, patch size and isolation accounted for up to 75% of the variation in patch immigration rate in the simulation study, and for 61% of the variation in interpatch movement in the field study. However, when the matrix was composed of a large number of cover types, the amount of explained variation dropped to as little as 33% for the simulation study and to 17% in the field study. Our results suggest that patch characteristics, such as patch size and isolation, may be poor predictors of interpatch movement when the landscape matrix is heterogeneous and when the organism responds to boundaries between different matrix cover types. These results imply that habitat patch- based models, such as those based on current metapopulation theory, will perform poorly in these situations. [ABSTRACT FROM AUTHOR]

Question: What is the nature and relative importance of compositional gradients within- and between fens? Location: Iowa, USA. Methods: 506 0.5 m × 0.5 m quadrats were sampled from 31 fens across a 550 km extent. Presence/absence of all vascular plant taxa, plus the non-vascular genera Sphagnum and Chara, and values for 24 environmental variables were noted. Global Non-Metric Multidimensional Scaling and Monte Carlo tests were used to describe compositional variation and identify significant environmental co-variables. Model-based cluster analysis was used to identify the optimal number of groups supported by the data, while k-means clustering was used to assign each quadrat to a group. The number of occurrences (and frequency) of each species within each group was calculated. Two-dimensional 95% Gaussian confidence intervals, ANOVA, correlation coefficient homogeneity tests, log-linear modelling, and Fisher's exact tests were used to document patterns of compositional change. Results: Two stable axes of variation were identified: the first being most closely correlated with soil pH, Mg, Ca, P, 5, vegetation height, surface and -10 cm soil temperature, site area, perimeter, perimeter/area ratio, growing season, and air temperature, with the second being most correlated to soil moisture, N, disturbance level, % organic matter, hummock height, N-S coordinate, and precipitation. Individual sites harboured between 20-47% of total compositional variation, with 28% of Axis 1 and 55% of Axis 2 scores being contained within-sites. Five compositional regions were identified that differed in the proportion of calciphile and hydrophile species. Compositional groups differed significantly between geologic types. Conclusions: While the principal axis of variation (corresponding to the rich-poor fen gradient) is present largely between sites, the second axis (corresponding to water level) is largely repeated within sites. Documentation and protection of vegetation patterns and species diversity within Iowa fens will thus require consideration of multiple sites across the landscape. [ABSTRACT FROM AUTHOR]

Roads are important components of landscapes; they fragment habitat, facilitate invasive species spread, alter hydrology, and influence patterns of land use. Previous research on the ecological impacts of roads may have underestimated their effect because currently available sources of road data do not include the full road network. We compared differences in road density and landscape pattern among U.S. Census Bureau TIGER line files, U.S. Geological Survey 1:100,000-scale digital line graphs, and U.S. Geological Survey 1:24,000-scale digital raster graphics in northern Wisconsin to road data derived from 1:40,000-scale digital orthophotos. Road density measured from digital orthophotos (2.82 km/km²) was significantly greater than that of digital raster graphics (1.62 km/km²) and more than double that of digital line graphs (1.21 km/km²) and TIGER (1.27 km/km²) data. The increased road densities in raster graphics and orthophoto data were mainly due to the addition of minor roads. When all roads were used to define patch boundaries, landscape metrics produced with orthophoto data showed significantly greater levels of fragmentation than those based on line or raster graphics. For example, maximum patch size was 1074 ha and total edge was 109 km for line graphs, compared with 686 ha and 211 km for orthophoto data. Roads are missing in commonly used data, primarily because mapping standards systematically exclude minor roads. These standards are not ecologically based and may result in false assumptions about the ecological effects of roads. We recommend that future studies take special consideration of the completeness of road data and consider whether all ecologically relevant roads are included. [ABSTRACT FROM AUTHOR]

This article addresses the application of ecological risk assessment at the regional scale to the prediction of impacts due to invasive or nonindigenous species (NIS). The first section describes risk assessment, the decision-making process, and introduces regional risk assessment. A general conceptual model for the risk assessment of NIS is then presented based upon the regional risk assessment approach. Two diverse examples of the application of this approach are presented. The first example is based upon the dynamics of introduced plasmids into bacteria populations. The second example is the application risk assessment approach to the invasion of a coastal marine site of Cherry Point, Washington, USA by the European green crab. The lessons learned from the two examples demonstrate that assessment of the risks of invasion of NIS will have to incorporate not only the characteristics of the invasive species, but also the other stresses and impacts affecting the region of interest. [ABSTRACT FROM AUTHOR]

Aim The local distribution of woody vegetation affects most functional aspects of semiarid landscapes, from soil erosion to nutrient cycling. With growing concern about anthropogenic climate change, it has become critical to understand the ecological determinants of woody plant distribution in semiarid landscapes. However, relatively little work has examined the determinants of local variation in woody cover. Here we examine water balance controls associated with patterns of tree cover density in a topographically complex semiarid woodland. Location Los Pinos Mountains, Sevilleta National Wildlife Refuge LTER, New Mexico, USA. Methods To explore the relationship between local water balance variation and tree cover density, we used a combination of high-resolution (1 × 1 m), remotely sensed imagery and quantitative estimates of water balance variation in space and time. Regression tree analysis (RTA) was used to identify the environmental parameters that best predict variation in tree cover density. Results Using six predictor variables, the RTA explains 39% of the deviance in tree cover density over the landscape. The relationship between water balance conditions and tree cover density is highly contingent; that is, similar tree cover densities occur under very different combinations of water balance parameters. Thus, the effect of one environmental parameter on tree cover density depends on the values of other parameters. After tree cover density is adjusted for water balance conditions, residual variation is related to tree cover density in the neighbourhood of a particular location. Conclusion In semiarid landscapes, vegetation structure is largely controlled by water supply and demand. Results presented here indicate that localized feedbacks and site-specific historical processes are critical for understanding the responses of semiarid vegetation to climate change. [ABSTRACT FROM AUTHOR]

We investigated habitat association of sympatric red-tailed hawks (Buteo jamaicensis) and northern goshawks (Accipiter gentilis) at 2 spatial scales centered on nest sites: (1) fine-scale patterns of forest structure and topography within 16-m radius circles (0.08 ha), and (2) midscale patterns of forested and nonforested areas, forest fragmentation, and topography within 2,085-m-radius circles (1,367 ha). Nonforested areas were defined as any area lacking > 20% canopy closure within a 30 x 30-m cell. At both scales, red-tailed hawk associations were more variable and goshawk associations less variable. At the fine scale, goshawks were consistently associated with open understories, tall trees, and gentle slopes (x = 9.6°, SD = 6.9) while red-tailed hawks were associated, on average, with steep, north-facing slopes (x = 17.4°, SD = 8.1) and dense understories. At the midscale, goshawks were consistently associated with patches of continuous forest and level terrain within 645 m of nest sites. Red-tailed hawks were associated with nonforested areas located within 105-645 m of nest sites and steep slopes within 105 m of nest sites. Forest fragmentation was greater around red-tailed hawk nest sites, and forested regions were more aggregated around goshawk nest sites when compared with the other species. These patterns indicate that on the Kaibab Plateau, redtailed hawks will gain habitat at the midscale and goshawks will lose habitat at both scales if forests are fragmented and mature forest structure is lost. [ABSTRACT FROM AUTHOR]

Abstract Aim Electronic distribution atlases and lists of ecological indicator values are becoming important tools in plant geography. In this contribution, we combine a geographical and an ecological data bank, and map out patterns of indicator value spectra (instead of single or average values) across a physiographically complex landscape. For our study, we select indicators of soil pH and carbonate content as key environmental factors that strongly affect overall plant diversity patterns in the temperate zone. Our goal is to relate the distribution and diversity of plant groups that are indicators of soil pH and carbonate content to environmental controls at the landscape-scale, and thus contribute to a causal understanding of species pools. Location We studied the Bavarian Alps, which represent the German portion of the Northern Alps. Methods Based on the existing floristic survey, we calculated relative frequencies of nine classes of indicator plants for soil pH and carbonate content in grid cells. The resulting attribute matrix (cells by indicator class frequencies) was subjected to principal components analysis and to k-means clustering. Results were compared and mapped out in the grid array of the whole region, resulting in continuous and discrete representations of species pool structure. We used a geographical information system to derive physiographical landscape properties from a geological map and a digital elevation model, and analysed their statistical relationship with the shapes of indicator spectra. Results and Main conclusions Averages of indicator values for soil pH and carbonate content follow the geological structure quite closely. Surprisingly, the diversity of indicator plant groups does not appear to be a function of geological or topographic heterogeneity. Rather, it seems to be related to areas of high elevation with uniform geology. The effect is a matter of additional acidophytes in high mountain areas and, in the high calcareous Alps, extreme calciphytes, while species with intermediate requirements are rarer than usual. For explanation, we suggest two facts: (1) a frequent lack of mature soils at high elevations and (2) particularities in soil genetic processes occurring under the harsh climatic conditions of high mountains. [ABSTRACT FROM AUTHOR]

Previous ordination studies of land snail community composition have been limited to four or fewer habitat types from sites separated by no more than 300 km. To investigate the nature of large-scale patterns, North American land snail assemblages at 421 sites, representing 26 habitat types and covering a 1400 × 800 km area, were ordinated using global, nonmetric multi-dimensional scaling (NMDS). These data were then subjected to model-based cluster analysis and kmeans clustering to identify the main compositional groups and most important environmental covariables. Six primary compositional groups were identified. Three of these largely represent upland forest and rock outcrop sites, while the remaining largely represent either lowland forest, lowland grassland or upland grassland habitats. The geographical location and moisture level of sites also influences community composition. A strong compositional difference exists between sites having duff vs. turf soil surface layers. Only 8% of sites were improperly classified when soil surface architecture was used as the sole predictor variable. Fully 43% of taxa exhibited significant preferences towards one of these surface types, while only 15% of relatively common (10 + occurrence) taxa showed no preferences. Twelve groups of closely related taxa within the same genus had members that favoured different surface types, indicating that differential selection pressures have existed over evolutionary time scales. While turf faunas appeared unaffected by anthropogenic disturbance, duff faunas were strongly impacted, suggesting that their conservation will require protection of soil surface architecture. [ABSTRACT FROM AUTHOR]

Abstract Aim The research explores how changes in disturbance regime resulting from human settlement may affect landscape structure. A spatially explicit grid-based simulation model is used to explore the interplay between humans, fire regime and landscape composition. Location The study site for this research is the botanical reserve at Mont Do, New Caledonia. The endemic conifer Araucaria laubenfelsii (Araucariaceae) forms a key component of the landscape at Mont Do. This species is unusual in that it is found scattered as an emergent in maquis and as a canopy species in adjacent rain forest patches. Although now dominated by a low maquis, prior to human settlement of New Caledonia, montane landscapes such as Mont Do are likely to have been heavily forested. Methods A spatially explicit simulation model, based on field data and palaeoecological information, was used to explore interactions between disturbance regime and the landscape. The model is described briefly here and more fully in Perry & Enright (2002) Ecological Modelling , 152 , 279. Results The model suggests that human-influenced changes to the fire regime at Mont Do have been important in generating the current landscape structure. The origin and maintenance of forest landscapes and maquis-forest mosaic landscapes are considered in the context of alternative stable states. Strong feedback loops between fire size and landscape composition, mediated at the smaller scale by other similar mechanisms, are capable of driving landscape change. The utility of a spatial state and transition modelling approach is demonstrated. Main conclusions The current landscape pattern on Mont Do is likely the result of changes to the fire regime occurring since human settlement. The specific mechanisms for this change outlined here may occur in a number of other similar systems. Understanding the origin and persistence of these ‘fire landscapes’ in New Caledonia and in the south-west Pacific in general is... [ABSTRACT FROM AUTHOR]

The article presents a study to examine the relationship between songbird relative abundance and local and landscape-scale habitat variables. In the study, researchers used partial-regression analysis to remove correlations between habitat variables measured at different spatial scales and between landscape composition and pattern variables.

Summary 1On many peatlands, a patterned landscape is formed by clusters of open-water pools enclosed by the peat of surrounding terrestrial and semi-aquatic habitats. Processes governing development of pool complexes operate over long time-scales (decades to millennia) that preclude direct observation and necessitate inferential analysis. 2We used present-day scaling relationships and spatial patterns of pools to test multiple hypotheses for development and dynamics of a bog pool complex in the Flow Country of northern Scotland. The complex included 641 permanent pools, ranging in surface area from 2.3 to 1930 m2 . 3Allometric scaling relationships and spatial analysis showed that the shape and distribution of pools is size- (or age-) dependent. With increasing size, pools became deeper relative to their surroundings and more convoluted and elongated in shape. Pool orientation and bathymetry were related to direction of slope. Small pools were located on the periphery of a focus now occupied by the largest pools. Peat depth varied systematically across the complex, leading to changes in both direction and gradient of water flow. 4The evidence suggests that pools formed initially where water tended to pond, and subsequently spread outward as the flat plateau expanded. Pools have accumulated sediment more slowly than surrounding areas, and the continued initiation of new pools seems to depend on this spatial variation in rates of sediment accumulation. Our study provides both a fuller understanding of the development of one pool complex, and techniques for comparative analysis of others. [ABSTRACT FROM AUTHOR]

The article presents a study which describes the value of a predictive model for seagrass bed coverage and its ecological attributes such as biomass and shoot density. It suggests that the prediction of seagrass landscape in hydrodynamic setting can be improved by increasing the spatial extent of sampling at a fixed resolution. The sampling scale and survey method reveals the need to carefully choose sampling designs to evaluate seagrass distribution and associated habitat characteristics.

The article presents a study which examines the behavioral mechanisms and habitat use by birds in the highly fragmented agricultural landscape of the Kellerberrin district of Western Australia. Modeling of patterns of species richness and foraging guilds with features of woodland patches, remnants using multiple regression analyses is offered. Results of the study indicating remnant area as the best variable for measures of community structure are discussed.

The article focuses on a study on the independent effects of forest cover and fragmentation on the distribution of forest breeding birds. Topics discussed include determine the relative importance of the independent effects of forest cover and fragmentation on the distribution of forest breeding birds, testing the hypothesis that the negative effect of forest fragmentation on species distribution increases with decreasing forest cover, and habitat fragmentation.