Natural Land Cover Research Articles

Evolution of urbanization and its impact on temperature trends of Quetta city in Pakistan

Quetta is an important economic, historical and culturally a rich city located in the south-west of Pakistan. Like many other cities of the world, Quetta faced massive urbanization during last three decades. It has 1.1 million populations. The consequences of rapid urbanization in Quetta city are significant through changing urban area’s temperatures than its nearby regional areas as a result of alteration of natural land cover change into built-surfaces at city scale. In this context, the objective of this study is to explore the effect of urbanization on variability of minimum (dTn) and maximum (dTx) temperature trends of Quetta city by comparing with non-urban regional stations. For this purpose, first the evolution of urbanization during 1980s to 2013 was analysed by using satellite image processing techniques for the years 1989, 2000 and 2013. To study the impact of urbanization on dTn and dTx of Quetta city, the time series data of daily average monthly minimum (Tn) and maximum (Tx) temperatures ranging from 1947 to 2013 of Quetta city and the seven regional stations were analysed by using linear regression. The results show that during last twenty years, urban population and urban surface area increased to 80% and 194%, respectively. The variation in annual and seasonal temperature trends depicted that Tn and Tx at Quetta city are increasing more than the regional stations and Tn increased faster than Tx at urban and regional scale except winter season.

The impact of exurban development on forested areas in Kurgan City, Russia

Exurban communities—a significant form of urban sprawl—can transform natural land cover. Exurban development refers to an expansion of communities located outside a city and its suburbs. One of the main reasons these settlements develop is a desire by residents to live closer to nature and developers’ recognition of the profitability of addressing this desire. Additionally, exurbs can become prosperous regions settled by people with high income. However, exurban development not only directly affects community patterns, but also species patterns, habitat reduction and disconnection, as well as land cover and land use alterations. The purpose of this paper is a quantitative analysis of the land cover transformation and forest fragmentation in Post-Soviet Russia, based on an empirical case study of the city of Kurgan. This case study also contributes to the overall research of urban sprawl in Russian provinces by adding to the discussion of homeowners’ behavior, regional environmental policies, and their role concerning the impacts of exurban settlements on the natural environment. This paper uses remote sensing imagery, census data, and primary data to analyze land cover change due to the emergence of exurban communities around Kurgan, Russia, with specific emphasis on the changes to native vegetation resulting from human behavior and stakeholder preferences.

Mapping the Land Cover of Africa at 10 m Resolution from Multi-Source Remote Sensing Data with Google Earth Engine

The remote sensing based mapping of land cover at extensive scales, e.g., of whole continents, is still a challenging task because of the need for sophisticated pipelines that combine every step from data acquisition to land cover classification. Utilizing the Google Earth Engine (GEE), which provides a catalog of multi-source data and a cloud-based environment, this research generates a land cover map of the whole African continent at 10 m resolution. This land cover map could provide a large-scale base layer for a more detailed local climate zone mapping of urban areas, which lie in the focus of interest of many studies. In this regard, we provide a free download link for our land cover maps of African cities at the end of this paper. It is shown that our product has achieved an overall accuracy of 81% for five classes, which is superior to the existing 10 m land cover product FROM-GLC10 in detecting urban class in city areas and identifying the boundaries between trees and low plants in rural areas. The best data input configurations are carefully selected based on a comparison of results from different input sources, which include Sentinel-2, Landsat-8, Global Human Settlement Layer (GHSL), Night Time Light (NTL) Data, Shuttle Radar Topography Mission (SRTM), and MODIS Land Surface Temperature (LST). We provide a further investigation of the importance of individual features derived from a Random Forest (RF) classifier. In order to study the influence of sampling strategies on the land cover mapping performance, we have designed a transferability analysis experiment, which has not been adequately addressed in the current literature. In this experiment, we test whether trained models from several cities contain valuable information to classify a different city. It was found that samples of the urban class have better reusability than those of other natural land cover classes, i.e., trees, low plants, bare soil or sand, and water. After experimental evaluation of different land cover classes across different cities, we conclude that continental land cover mapping results can be considerably improved when training samples of natural land cover classes are collected and combined from areas covering each Köppen climate zone.

Effectiveness of private land conservation areas in maintaining natural land cover and biodiversity intactness

Private land conservation areas (PLCAs) are increasingly looked to for meeting the deficit left by state-owned protected areas in reaching global conservation targets. However, despite the increasing extent and recognition of PLCAs as a complementary conservation strategy, little research has been done to quantify their effectiveness; a critical consideration if they are to be counted towards international biodiversity conservation targets. The long history of PLCAs in South Africa provides an interesting case study to address this knowledge gap. Here, we quantified the effectiveness of South African PLCAs by comparing losses in natural land cover and biodiversity intactness within PLCAs with different levels of protection to that of unprotected control points. Points within PLCAs were matched with unprotected control points to test the prediction that if PLCAs offer effective protection, losses in natural land cover and biodiversity intactness would be significantly lower within their boundaries in comparison to unprotected controls exposed to similar conditions. Consequences of natural land cover loss on biodiversity intactness were thus assessed, thus advancing standard approaches for quantifying effectiveness. Between 1990 and 2013, PLCAs lost significantly less natural land cover (3%) and biodiversity intactness (2%) than matched unprotected areas (6% and 4%, respectively). Of the natural land cover lost within PLCAs, most was converted to cultivated land. Farms can support more species than other land uses (e.g. mines), a likely explanation for why losses in biodiversity intactness were less than losses in natural land cover. Contrary to the predicted pattern, effectiveness did not increase with level of protection; informal PLCAs with no legal protection had comparable natural land cover and biodiversity intactness retention to strictly protected PLCAs, with most losses recorded among PLCAs with moderate protection. This study provides the first national-scale evidence that PLCAs can be an effective mechanism for conserving natural land cover and biodiversity intactness, which is highly relevant given current discussions around their likely long-term biodiversity conservation capacity.

Fragmentation and thresholds in hydrological flow-based ecosystem services.

Loss and fragmentation of natural land cover due to expansion of agricultural areas is a global issue. These changes alter the configuration and composition of the landscape, particularly affecting those ecosystem services (benefits people receive from ecosystems) that depend on interactions between landscape components. Hydrological mitigation describes the bundle of ecosystem services provided by landscape features such as woodland that interrupt the flow of runoff to rivers. These services include sediment retention, nutrient retention and mitigation of overland water flow. The position of woodland in the landscape and the landscape topography are both important for hydrological mitigation. Therefore, it is crucial to consider landscape configuration and flow pathways in a spatially explicit manner when examining the impacts of fragmentation. Here we test the effects of landscape configuration using a large number (>7,000) of virtual landscape configurations. We created virtual landscapes of woodland patches within grassland, superimposed onto real topography and stream networks. Woodland patches were generated with user‐defined combinations of patch number and total woodland area, placed randomly in the landscape. The Ecosystem Service model used hydrological routing to map the “mitigated area” upslope of each woodland patch. We found that more fragmented woodland mitigated a greater proportion of the catchment. Larger woodland area also increased mitigation, however, this increase was nonlinear, with a threshold at 50% coverage, above which there was a decline in service provision. This nonlinearity suggests that the benefit of any additional woodland depends on two factors: the level of fragmentation and the existing area of woodland. Edge density (total edge of patches divided by area of catchment) was the best single metric in predicting mitigated area. Distance from woodland to stream was not a significant predictor of mitigation, suggesting that agri‐environment schemes planting riparian woodland should consider additional controls such as the amount of fragmentation in the landscape. These findings highlight the potential benefits of fragmentation to hydrological mitigation services. However, benefits for hydrological services must be balanced against any negative effects of fragmentation or habitat loss on biodiversity and other services.

Low conservatism of leafhopper communities in remnant and reconstructed prairie sites in a working agroecological landscape

Leafhoppers (Hemiptera: Cicadellidae) form a large, diverse insect family that contributes significantly to trophic interactions and pathogen transmission in grasslands. We compared leafhopper communities of five remnant prairies and five prairie reconstructions in northeastern Kansas, USA. We hypothesized that leafhopper communities would be more conservative (i.e., greater dependence on prairies) and diverse on remnant as compared to reconstructed prairies, and that remnants would support more grass-feeders. We also predicted that sites surrounded by natural/semi-natural landscapes would have greater leafhopper diversity. We found grass feeders represented a higher proportion of leafhoppers on remnants. We found, however, no difference in mean conservatism between remnants and reconstructions, and overall levels of conservatism were lower than other grassland data sets. Mean conservatism was greater in the mid-summer than in early summer, where migratory pests such as Macrosteles were abundant. Although remnants and reconstructed prairies didn’t differ in leafhopper diversity, diversity increased with forb percent cover. The amount of natural and semi-natural land cover around sites had complex relationships with leafhopper diversity and composition. For future studies, we encourage coordinated studies on leafhopper communities across the tallgrass prairie region, with a particular focus on conservatism. Deciphering the effect of survey times, and grassland size and management, on prairie-dependent leafhoppers is important. We predict that large numbers of migratory species may lead to greater homogeneity in leafhopper communities across sites early in the season. Over time, site types and landscape features may progressively filter species and amplify local specialists, resulting in more late-season variation among sites.

Is habitat conversion likely to impede the ability of bird species to track changing climate?

As climate changes, species’ ranges may shift poleward. However, habitat loss in intervening areas has been hypothesized potentially to impede the movements of these species. Populations near range margins offer opportunities to study how marginal species have reacted to habitat loss. We examined the presence/absence of bird species in landscapes that were historically mainly forested (natural land covers) in Southern Ontario, Canada. We used logistic regression to determine each bird species’ probability of occupancy (pocc) as a function of natural cover in 991 landscapes, each 100-km2. We distinguished three groups of species: i) southerly species whose northern range limits fall in the study area (n=37), ii) northerly species whose southern range limits fall in the study area (n=35), and iii) mid-range species (n=106). We compared pocc for these three groups of species in six different habitat guilds. We found that species near their southern range edges are less likely to occur in landscapes where forest amount is reduced, while species near their northern range edge are more likely to occur in landscapes with reduced forest. This result is independent of habitat guild. Our results are inconsistent with the hypothesis in the climate change literature proposing that loss of natural land cover near poleward range margins would inhibit range expansion in response to climatic warming. Rather, we hypothesize that, at southern range edges, the dual stresses of climatic warming and forest conversion both reduce species’ ability to occupy a landscape. However, near northern (potentially expanding) range edges, partially disturbed landscapes are more readily invaded than undisturbed landscapes.

Landscape‐level environmental stressors contributing to the decline of Poweshiek skipperling (Oarisma poweshiek)

Abstract1. The Poweshiek skipperling [Oarisma poweshiek (Parker, 1870; Lepidoptera: Hesperiidae)] is a federally endangered butterfly that was historically common in prairies of the upper Midwestern United States and Southern Manitoba, Canada. Rapid declines over the last 20 years have reduced the population numbers to four verified extant sites. The causes of Poweshiek skipperling decline are unknown. 2. We aggregated all known Poweshiek skipperling occurrence records to examine the spatiotemporal patterns of Poweshiek skipperling decline. Ecological niche models were developed for five time frames (1985, 1990, 1995, 2000 and 2005) and three spatial extents (eastern occupied range, western occupied range and total occupied range). We used a backward elimination method to investigate the effects of climate and land use on the ecological niche of Poweshiek skipperling. 3. Predictors of occurrence changed over time and across the geographical extent of Poweshiek skipperling. Land use covariates were retained in east models. In the west and total extent, climate variables contributed the most to model predictive power for the 1985, 1990 and 1995 models; land use variables contributed the most to model predictive power in the 2000 and 2005 models. 4. During the rapid decline in Poweshiek skipperling population numbers occurring at the turn of the century, probability of Poweshiek skipperling presence was being driven by proportion of natural land cover and distance to nearest grassland/wetland. Our results suggest that these land use variables are important landscape‐level variables to consider when developing risk assessments of extant populations and potential reintroduction sites.

Spatial ecology of coyotes in the urbanizing landscape of the Cuyahoga Valley, Ohio.

Urban landscapes can present ecological challenges for wildlife species, yet many species survive, and even thrive, near dense human populations. Coyotes (Canis latrans), for example, have expanded their geographic range across North America and, as a result of their adaptability and behavioral flexibility, are now a common occupant of many urban areas in the United States. We investigated the spatial ecology of 27 coyotes fitted with Global Positioning System (GPS) telemetry collars radio-collared in the Cuyahoga Valley, Ohio. Our objectives were to quantify coyote space use, evaluate resource selection, and investigate coyote movement and activity patterns. To measure space use, we estimated home range (95%) and core area (50%) size of coyotes using the adaptive local convex hull (a-LoCoH) method. We found the mean (± SE) home range size of resident coyotes (4.7 ± 1.8 km2) was significantly smaller than ranges of transient coyotes (67.7 ± 89.6 km2). Similarly, mean (± SE) core area size of resident coyotes (0.9 ± 0.6 km2) was significantly smaller than core areas of transient coyotes (11.9 ± 16.7 km2). Home range and core area size of both resident and transient coyotes did not vary by sex, age, or season. For all coyotes, use of natural land cover was significantly greater than use of altered and developed land. When coyotes were using altered and developed land, GPS fixes were most common at night. Coyote movement patterns differed with respect to status, time period, and season; peaking during nighttime hours. A better understanding of coyote space use and movement within anthropogenic landscapes aids management of people, parks, and wildlife by providing the data necessary for research-based management decisions.

Environmental vulnerability assessment of Choghakhor International Wetland during 1985 to 2018

AbstractAs of natural constraints, and the specific climate of Iran, as well as the increasing importance of international water resources in the socio‐economic development of societies, studies on surface water resources, especially wetlands, merit special attention. Accordingly, the TM, ETM+ and OLI satellite images of 1985, 2000 and 2018 were used in the present study to detect changes in the Choghakhor international wetland. Classifying the images with a supervised method, and using maximum likelihood algorithms, the distinct land use/land cover classes of waterbody, aquatic plants, pasture and forest, agricultural lands, bare land and human built lands were ranked. Selected landscape metrics information on the spatial pattern of the Choghakhor wetland was quantitatively determined, using Fragstats software, and the spatial composition and vulnerability of the wetland were evaluated. The vulnerability assessment of wetland contamination was investigated using the WRASTIC index based on the catchment area scale. Time processing of the data obtained from the maps indicated a 26.63% decrease in the pasture and forest area, and a 12.1% increase in the area of human built lands and agriculture lands during the period from 1985 to 2018. Further, in spite of the waterbody area expanding during 1985 to 2000, it subsequently shrunk in size from 2000 to 2018, with the area of aquatic plants lands increasing during the same period. Analysis of landscape metrics generally indicated the natural wetland cover has been changing during this period along with increasing anthropogenic impacts. Degradation, rotation and replacement of natural land cover such as pastures and forests with human built areas can be considered undesirable development effects on the Choghakhor wetland. The results of the WRASTIC index calculation indicated a major impact of Choghakhor wetland components from water pollution. The results of the present study place an emphasis on more sustainable land use and prevention of land destruction in the Choghakhor wetland basin.

Optimal site selection for solar photovoltaic (PV) power plants using GIS and AHP: A case study of Malatya Province, Turkey

The importance of energy needs increases substantially with the effects of scientific developments, technological improvements and human population growth. Because of excessive consumption of non-renewable energy resources and rising expenses, the vast majority of nations are in constant search of new resources. In Turkey, electricity produced from solar energy systems plays a key role in supplying energy demands because the geographic location of Turkey is suitable to benefit from solar energy systems. In this study, the construction of solar photovoltaic (PV) power plant within the Malatya Province of Turkey was identified by using Geographical Information Systems (GIS) technology. Within this framework, many effective factors were generated including solar energy potential, roads, energy transmission lines, transformer centers, slope, aspect, location of dams and rivers, natural gas pipelines, fault lines, land cover and residential areas. Using the Analytical Hierarchy Process method, factor weights were then calculated. As a result of all these processes, a map was presented demonstrating the optimal locations for solar energy plants. Finally, results were compared with existing solar photovoltaic (PV) power plants. An empirical study that produces the most optimal solution for decision makers to site selection for solar power plants has been realized.

Quantification and mapping of the spatial landscape pattern and its planning and management implications a case study in Addis Ababa and the surrounding area, Ethiopia

ABSTRACT Rapid urbanization in Addis Ababa and the surrounding area resulted in the rapid land use/land cover (LULC) change that affected landscape structures and ecological functions. This study aimed at quantifying and mapping the spatial patterns of landscape structure for a sustainable city region landscape conservation planning and management. GIS and statistical tools were used to compute important landscape metrics. Pearson Correlation and factor analysis were also applied to reduce redundant indices and identify underlining factor of the landscape structure by network of hexagonal area. The analysis depicted four landscape and four class-level underlined metrics. Accordingly, as the region overall landscape was characterized by patch size and density, shape and texture (interspersion) index, the forest class also attributed by patch size and density, and shape metrics. The result shows that the region landscape planning and management schemes must emphasize on the level of patch fragmentation and landscape complexity to maintain the natural land cover habitat functioning, the amount of ecological process and extent of human intervention. This research will help scientific base decision-making in conservation planning and management of the tropical highland urban landscape in general, and the study area in particular.

Monitoring and Prediction of Land Use Land Cover Changes and its Impact on Land Surface Temperature in the Central Part of Hisar District, Haryana Under Semi-Arid Zone of India

Abstract Land use Land cover have significance in relation to Land, the most vital and fundamental resource pertaining to the urban development. Unprecedented urban growth has a noteworthy impact on natural landscape by converting natural land-cover in Haryana. Hisar, an area recognized for rapid urban growth is less explored in terms of research. The present research has shown a significant change in land use in terms of expansion of built-up area from 3.7 % (1991) to 5.0 % (2001) and 6.2 % (2011) by encroaching into agricultural land. Despite the clear difference between average land surface temperature for built up and non-built up area, grazing land and sandy waste, bare land in the rural surrounding possess higher temperature compared to the city core which contradicts the reported impact of urbanization earlier. Such contrary pertains to sparse vegetation cover leading to reduced evaporative cooling during dry pre-monsoon summer in the rural surrounding. On the other side, green parks and plantation in the city contribute to lower mean temperature because of high rates of evapotranspiration and produce ‘oasis effect’ in the present study area located in semi-arid climatic zone. Regression analysis between temperature and Normalized Difference Vegetation Index, Normalized Difference Built-up Index exhibited a strong negative and positive correlation respectively (Pearson’s r: between -0.79 to -0.87 and between 0.79 to 0.84 respectively). Future land use prediction project an increase (1.3 %) in built-up area from 2011 to 2021. This study recommends urban plantation and prohibition to overgrazing to check the heat effect.

Attribution analyses of evapotranspiration and gross primary productivity changes in Ziya-Daqing basins, China during 2001–2015

Evapotranspiration (ETa) and gross primary productivity (GPP) are two of the key flux indices in a basin system. This study investigated the evolutions of ETa and GPP and the contributions of climate variables and vegetation index over multiple land cover types, simulated by the VIP model (Vegetation Interfaces Processes, RS version) with Terra-Modis 250 m Normalized Difference Vegetation Index (NDVI) dataset in the Ziya-Daqing basins (ZDB), China, during 2001–2015. The nonparametric Mann-Kendall test was used to analyze the changes in ETa and GPP. Contributions to the variations of ETa and GPP were explored using a differential equation method. The analyses revealed that ETa and GPP were high in the eastern plain, and spatial distributions were mainly associated with distributions of the major land-cover types. ETa and GPP showed positive trends in the western Taihang Mountains and negative trends in the eastern plain region. The annual ETa and GPP increased from 2001 to 2015 in most land-use types except cropland and urban. The decreases in ETa and GPP were primarily attributed to solar dimming in cropland and urban. The increases in ETa and GPP mainly occurred in the natural land-cover types (e.g., mixed forest and grassland) as a tradeoff between the positive effect of greening and the negative effect of declined radiation. In ZDB, the contributions of net radiation, air temperature, wind speed, and leaf area index to the change in ETa were − 0.681%, − 0.379%, − 0.032%, and 1.442%, respectively. The contributions of net short-wave radiation, air temperature, relative humidity, and fraction of photosynthetically active radiation to the change in GPP were − 2.411%, 0.085%, − 0.020%, and 10.224%, respectively. Thus, the “greening” was the major reason for ETa and GPP increases in natural vegetations, whereas solar dimming was the major reason for ETa and GPP decreases in cropland.

Probabilistic hazard assessment of contaminated sediment in rivers

We propose a probabilistic framework rooted in multivariate and copula theory to assess heavy metal hazard associated with contaminated sediment in freshwater rivers that provide crucial ecosystem services such as municipal water source, eco-tourism, and agricultural irrigation. Exploiting the dependence structure between suspended sediment concentration (SSC) and different heavy metals, we estimate the hazard probability associated with each heavy metal at different SSC levels. We derive these relationships for warm (spring-summer) and cold (fall-winter) seasons, as well as stormflow condition, to unpack their nonlinear associations under different environmental conditions. To demonstrate its efficacy, we apply our proposed generic framework to Fountain Creek, CO, and show heavy metal concentration in warm season and under stormflow condition bears a higher hazard likelihood compared to the cold season. Under both warm season and stormflow conditions, probability of exceeding maximum allowable threshold for all studied heavy metals (Cu, Zn, and Pb, in recoverable form) at a standard hardness of 100 mg/lCaCo3 and at a high level of SSC (95th percentile) is consistently more than 80% in our study site. Moreover, a longitudinal study along the Fountain Creek demonstrates that urban and agricultural land use considerably increase likelihoods of violating water quality standards compared to natural land cover. The novelty of this study lies in introducing a probabilistic hazard assessment framework that enables robust risk assessment with important policy implications about the likelihood of different heavy metals violating water quality standards under various SSC levels.

Greenspace access does not correspond to nature exposure: Measures of urban natural space with implications for health research

Urban natural spaces have gained increasing attention in the public health agenda due to their reported association with better health outcomes. Improved measurement of urban natural spaces and a better understanding of the relative effects of different types of natural space in different socio-geographical contexts are required to optimize evidence for urban planning. This case study of Metro Vancouver examines relationships between different accessibility and exposure metrics, the distribution of different land cover types across an urban-rural gradient, and the correlation to area-level marginalization. Local land use and land designation data were used to assess accessibility to public greenspace, a high-resolution land cover dataset was used to determine residential exposure to different land cover types, and the widely applied CAN-Marg index was used to obtain information on area-level marginalization. In addition to descriptive statistics, correlation coefficients were computed to determine relationships between the different variables. Access to public greenspace was weakly correlated with measures of residential exposure to natural land cover types. Although residential exposure varied with level of urbanization, access to public greenspace remained relatively constant across the region. Both access and exposure were significantly correlated with three Can-Marg dimensions: residential instability, material deprivation and ethnic concentration. We recommend that future health research include assessment of both access and exposure as distinct measures, as well as consideration of geographical and social context to potentially target urban green planning for maximal population health impacts.

A multi-taxa functional diversity assessment of the effects of eco-estate development in the mixed land-use mosaic of the KwaZulu-Natal North Coast, South Africa

Global biodiversity is currently under threat from human population expansion and the required land transformation for shelter and resources. Land transformation, in the form of agriculture or urbanisation is believed to reduce habitats and their resources, increase fragmentation of natural habitats, and increase the likelihood of successful invasion by exotic species. These all affect existing biodiversity, its structure, and the ecosystem services which it provides. In recent years, development from natural and agricultural (mainly sugarcane) land into eco-estates (housing developments with the intention of conserving the environment) has become increasingly popular along the north coast of KwaZulu-Natal (KZN), South Africa. However, research on their impacts on the local environment is limited. We predicted that these eco-estates are, by their design, improving the functional diversity of amphibians, birds, and mammals, and ultimately ecosystem functioning. A multi-taxa assessment of the three components of functional diversity (functional richness, functional evenness, and functional divergence) suggested that eco-estate development was improving certain components for each of the taxa assessed. However, the management and development of these eco-estates was the key determinant. Eco-estates with increased interconnected indigenous forest and thicket/dense bush, with reduced housing and road density, exhibited improved functional diversity in comparison with those more densely inhabited containing isolated natural land-cover patches. We believe that these eco-estates could provide an effective mitigation method of population expansion whilst maintaining ecosystem health, but only under the recommended development and management plans.

The homogenizing influence of agriculture on forest bird communities at landscape scales

Agricultural expansion is a principal driver of biodiversity loss, but the impacts on community assembly in agro-ecosystems are less clear, especially across regional scales at which agricultural policies are applied. Using forest-breeding birds, we (1) tested whether increased agricultural coverage resulted in species communities that were random or more similar than expected, (2) compared the relative influence of agriculture versus distance in structuring communities, and (3) tested whether different responses to agriculture among functional guilds leads to a change in functional diversity across gradients of agriculture. Species abundances were sampled along 229 transects, each 8 km, using citizen science data assembled across a broad region of eastern Canada. Agricultural and natural land cover were each summed within three different-sized buffers (landscapes) around each transect. A null modeling approach was used to measure community similarity. Communities were most similar between landscapes that had high agricultural coverage and became more dissimilar as their respective landscapes differed more strongly in the amount of agriculture. Community dissimilarity increased with geographic distance up to about 200 km. Dissimilarity with increasing agriculture was largely due to the disappearance of Neotropical migrants, insectivores and foliage-gleaners from the community as agriculture increased. Functional diversity declined with increasing agriculture but less strongly than species richness and only when agriculture exceeded 40% of the landscape. Our results support the hypothesis that increasing agricultural coverage produces a filtering towards communities of agriculture-tolerant forest birds with a loss of functional diversity and high site-to-site community similarity.

CREATING WALLONIA'S NEW VERY HIGH RESOLUTION LAND COVER MAPS: COMBINING GRASS GIS OBIA AND OTB PIXEL-BASED RESULTS

Abstract. The Walloon region of Belgium has launched a research project that aims at elaborating a methodology for automated, high-quality land cover mapping, based primarily on its yearly 0.25m orthophoto coverage. Whereas in urban areas an object-based (OBIA) approach has been the privileged path in the last years as it allows taking into account shape information relevant for the characterization of man-made constructions, such an approach has its limits in the rural and more natural areas due to increased difficulties for segmentation and less sharp boundaries, thus calling for a pixel-based approach. The project thus consists in developing a combination of methods, and to integrate their results through an ensemble fusion approach. As many of the more natural land cover classes have temporal profiles which cannot be detected in a one-date orthoimage, Sentinel 1 and 2 data are also included in order to take advantage of their higher spectral and temporal resolution. All methods are trained using existing regional databases. In a second step, we combine the different LC classification results by fusioning them into one high-accuracy (over 90% OA) product, using a series of different approaches ranging from rule-based to machine learning to the Dempster-Shafer method. The entire toolchain is based on free and open source software, mainly GRASS GIS and Orfeo ToolBox. Results indicate the importance of the quality of the individual classifications for the fusion results and justify the choice of combining OBIA and pixel-based approaches in order to avoid the pitfalls of each.

Diverse policies leading to contrasting impacts on land cover and ecosystem services in Northeast China

Abstract Understanding where important ecosystem services originate in space and how they change in time is essential for sustainable ecosystem management. Spatially explicit information of integrated changes in land cover and ecosystem services impacted by diverse policies has been unavailable in Northeast China, limiting the improvement of human well-being. Therefore, this study integrated remote sensing, meteorological records, and statistical data to evaluate the impacts of policies on land cover and ecosystem services from 2000 to 2015. The results reveal that diverse policies induced both notable changes in land cover, as well as geospatially varied changes in ecosystem services. Specifically, agricultural cultivation was still the dominant factor driving the losses of woodland, grassland, and wetland, while large areas of croplands have been returned to natural land cover, including a net area increase in woodland (2256 km2). Cropland expansion occurred at the expense of wetland (7121 km2), while the expansion of built-up land was converted primarily from cropland (62.8%). Marked decrease in water yield was observed, while sandstorm prevention, habitat suitability, and grain production have been enhanced on the scale of Northeast China. Moreover, soil retention and ecosystem carbon stock decreased slightly. In terms of present policies and changes in ecosystem services, it is important to rethink the emphasis on food production, reduce policy-driven natural ecosystem losses, and enhance the effectiveness of ecological projects. The findings are expected to help achieve win-win outcomes between ecological conservation and social-economic development in Northeast China.