scholarly journals Assessing Environmental Criteria to Support Forest Connectivity

2021 ◽  
Author(s):  
Ivan Vanderley-Silva ◽  
Roberta Valente
Keyword(s):  
Urban Sprawl ◽  
Forest Structure ◽  
Urban Expansion ◽  
Forest Fragments ◽  
Ecological Processes ◽  
Forest Connectivity ◽  
Landscape Characteristics ◽  
Environmental Criteria ◽  
Forest Attributes ◽  
The Impact

Abstract Establishing forest connection in landscapes under urban sprawl is essential for maintaining the ecological processes and ensuring biodiversity conservation. However, the major challenge is incorporated the ecological network in the land-use/land-cover planning. This way, the main objective of the study was the evaluation of environmental criteria for prioritizing areas to obtain forest functional connectivity in a landscape subject to the urban sprawl. The second objective was to understand how the criteria are associated with the structural forest attributes represented by traditional landscape ecology metrics. The criteria were defined through the literature review, representing the landscape characteristics as the topographic, conflicts, and biotics. The metrics used to characterize the forest structure were perimeter, shape index, and distance to the nearest neighbor. They were generated to a selected group of forest remnants, which represent the landscape forest structure. Sampling the criteria and forest fragments maps (i.e., different maps representing the metrics-values) through the hexagon network, we assessed how the criteria are associated with the structural forest attributes. The statistical analysis used to evaluate these sampled values were The Moran Global (Moran I) and Moran Local (LISA). We obtained that the urban expansion process is diffuse, although it does not occur randomly in our landscape. The criteria slope, TWI, distance from drainage network, distance from highways, distance from the low-density urban area, and distance from forest patches have characteristics that support this process. Furthermore, our results indicated a spatial autocorrelation among metrics and after, among metrics and these criteria. Also, we obtained that the external influences on the fragments did not occur randomly and that the criteria act on the landscape. This way, through these criteria, we can identify regions where it is possible to have the persistence of forest fragments, even though in places under the impact of urban sprawl.

scholarly journals The Impact of Risk Preference in Decision Behavior on Urban Expansion Morphology

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Zhangwei Lu ◽  
Lihua Xu ◽  
Yaqi Wu ◽  
Yijun Shi ◽  
Jinyang Deng ◽  
...  
Keyword(s):  
Urban Sprawl ◽  
Rapid Development ◽  
Urban Expansion ◽  
Risk Preferences ◽  
Land Development ◽  
Decision Makers ◽  
Economic Interests ◽  
Driving Mechanisms ◽  
The Impact ◽  
Executive Ability

With the rapid development of urbanization, the urban expansion morphology has been changing with complex driving mechanisms behind the urban evolution process. This article simulates the results of urban land development contingent upon decision-makers’ risk preferences and reveals the inherent law of the effect of risk preferences on urban expansion morphology. Results show that cautious decision-makers lead to the urban expansion morphology being relatively compact, and the reckless decision-makers lead the urban expansion to sprawl. Moreover, there are obvious differences in strengths of planning constraints on the decision-makers with different risk preferences. The reckless decision-makers, driven by the economic interests, are more likely to break through the planning, especially when the planning is not reasonable. It is also found that enhancing executive ability of planning for the reckless decision-makers can promote compactness of the urban expansion morphology. However, the effect of enhancing executive ability of planning on the cautious decision-makers is limited. Thus, in the case of unreasonable planning, the executive ability of planning to the reckless decision-makers should be enhanced so as to avoid urban sprawl.

scholarly journals Urban Sprawl Mapping through Geo-Informatics and Impact on Land use and Landcover of Kakinada Municipal Corporation in Andhra Pradesh, India.

2020 ◽  
Vol 9 (2) ◽  
pp. 373-378
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Urban Sprawl ◽  
Water Body ◽  
Urban Expansion ◽  
Natural Increase ◽  
Infrastructure Development ◽  
Dry Land ◽  
Gis And Remote Sensing ◽  
The Impact

Urban infrastructure and urban sprawl required the idea of preparing a proper management plan to avoid the unwanted environmental and economic impacts that come with it. The main objective of the research is to map the urban sprawl using Geospatial technology and t its impact on land use and land cover. The increase in the rate of population over the last two decades is equally responsible for the urban expansion and subsequent infrastructure development. The results of the integrated geospatial study shows that the urban expansion of Kakinada Municipal Corporation was largely caused by the increase in built-up area from 29.67% in 1995, 44.86% in 2011 to 51.34% in 2017 to 62.84% in 2019 out of Kakinada’s township area of 189552.6 ha mainly due to natural increase of the population and rural ward migration. Vegetation area was 50.68% in 1995 and has declined to 37.82% in 2011. However, the percentage of vegetation experienced a hike and covered 40.23% in 2017 and then went downhill with a land cover percentage of 34.04% of the total township by the year 2019. Over the last two decades the water-body and the dry land were largely converted into built-up areas. The decline of 49151 ha of water-body due mainly because of the urban expansion and the dry-land lost nearly 27200.79 ha of its land cover to the built-up areas. Therefore, controlling and monitoring of urban expansion using GIS and remote sensing technologies are vital solutions to assess the impact of urban expansion of land use and land cover.

Impact of LULC Changes on LST in Rajshahi District of Bangladesh: A Remote Sensing Approach

2020 ◽  
Vol 3 (1) ◽  
pp. 11-23 ◽  
Author(s):  
Abdulla Al Kafy ◽  
Abdullah Al-Faisal ◽  
Mohammad Mahmudul Hasan ◽  
Md. Soumik Sikdar ◽  
Mohammad Hasib Hasan Khan ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Surface Temperature ◽  
Land Surface ◽  
Agricultural Land ◽  
Global Climate ◽  
Urban Expansion ◽  
Water Bodies ◽  
Landsat 8 ◽  
Lulc Changes ◽  
The Impact

Urbanization has been contributing more in global climate warming, with more than 50% of the population living in cities. Rapid population growth and change in land use / land cover (LULC) are closely linked. The transformation of LULC due to rapid urban expansion significantly affects the functions of biodiversity and ecosystems, as well as local and regional climates. Improper planning and uncontrolled management of LULC changes profoundly contribute to the rise of urban land surface temperature (LST). This study evaluates the impact of LULC changes on LST for 1997, 2007 and 2017 in the Rajshahi district (Bangladesh) using multi-temporal and multi-spectral Landsat 8 OLI and Landsat 5 TM satellite data sets. The analysis of LULC changes exposed a remarkable increase in the built-up areas and a significant decrease in the vegetation and agricultural land. The built-up area was increased almost double in last 20 years in the study area. The distribution of changes in LST shows that built-up areas recorded the highest temperature followed by bare land, vegetation and agricultural land and water bodies. The LULC-LST profiles also revealed the highest temperature in built-up areas and the lowest temperature in water bodies. In the last 20 years, LST was increased about 13ºC. The study demonstrates decrease in vegetation cover and increase in non-evaporating surfaces with significantly increases the surface temperature in the study area. Remote-sensing techniques were found one of the suitable techniques for rapid analysis of urban expansions and to identify the impact of urbanization on LST.

Kalahari Cheetahs

2017 ◽  
Author(s):  
Gus Mills ◽  
Margaret Mills
Keyword(s):  
Reproductive Success ◽  
Spatial Ecology ◽  
Prey Selection ◽  
Arid Ecosystems ◽  
Foraging Success ◽  
Ecological Processes ◽  
Demographic Groups ◽  
Important Prey ◽  
Hunting Behaviour ◽  
The Impact

This book demonstrates how cheetahs are adapted to arid savannahs like the southern Kalahari, and makes comparisons with other areas, especially the Serengeti. Topics dealt with are: demography and genetic status; feeding ecology, i.e. methods used for studying diet, diets of different demographic groups, individual diet specializations of females, prey selection, the impact of cheetah predation on prey populations, activity regimes and distances travelled per day, hunting behaviour, foraging success and energetics; interspecific competition; spatial ecology; reproductive success and the mating system; and conservation. The major findings show that cheetahs are well adapted to arid ecosystems and are water independent. Cheetah density in the study area was stable at 0.7/100 km2 and the population was genetically diverse. Important prey were steenbok and springbok for females with cubs, gemsbok, and adult ostrich for coalition males, and steenbok, springhares, and hares for single animals. Cheetahs had a density-dependent regulatory effect on steenbok and springbok populations. Females with large cubs had the highest overall food intake. Cheetahs, especially males, were often active at night, and competition with other large carnivores, both by exploitation and interference, was slight. Although predation on small cubs was severe, cub survival to adolescence was six times higher than in the Serengeti. There was no difference in reproductive success between single and coalition males. The conservation priority for cheetahs should be to maintain protected areas over a spectrum of landscapes to allow ecological processes, of which the cheetah is an integral part, to proceed unhindered.

scholarly journals Sources of and Control Measures for PTE Pollution in Soil at the Urban Fringe in Weinan, China

Land ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 762
Author(s):  
Lei Han ◽  
Rui Chen ◽  
Zhao Liu ◽  
Shanshan Chang ◽  
Yonghua Zhao ◽  
...  
Keyword(s):  
Land Use ◽  
Urban Expansion ◽  
Pollution Sources ◽  
Urban Fringe ◽  
Control Measures ◽  
Atomic Fluorescence Spectrometry ◽  
Human Beings ◽  
Rapid Urbanization ◽  
Kriging Interpolation Method ◽  
The Impact

The environment of the urban fringe is complex and frangible. With the acceleration of industrialization and urbanization, the urban fringe has become the primary space for urban expansion, and the intense human activities create a high risk of potentially toxic element (PTE) pollution in the soil. In this study, 138 surface soil samples were collected from a region undergoing rapid urbanization and construction—Weinan, China. Concentrations of As, Pb, Cr, Cu, and Ni (Inductively Coupled Plasma Mass Spectrometry, ICP-MS) and Hg (Atomic Fluorescence Spectrometry, AFS) were measured. The Kriging interpolation method was used to create a visualization of the spatial distribution characteristics and to analyze the pollution sources of PTEs in the soil. The pollution status of PTEs in the soil was evaluated using the national environmental quality standards for soils in different types of land use. The results show that the content range of As fluctuated a small amount and the coefficient of variation is small and mainly comes from natural soil formation. The content of Cr, Cu, and Ni around the automobile repair factory, the prefabrication factory, and the building material factory increased due to the deposition of wear particles in the soil. A total of 13.99% of the land in the study area had Hg pollution, which was mainly distributed on category 1 development land and farmland. Chemical plants were the main pollution sources. The study area should strictly control the industrial pollution emissions, regulate the agricultural production, adjust the land use planning, and reduce the impact of pollution on human beings. Furthermore, we make targeted remediation suggestions for each specific land use type. These results are of theoretical significance, will be of practical value for the control of PTEs in soil, and will provide ecological environmental protection in the urban fringe throughout the urbanization process.

scholarly journals A multiscale assessment of Red-tailed Hawk reproductive success relative to urban density and habitat type

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Justin H White ◽  
Jessi L Brown ◽  
Zachary E Ormsby
Keyword(s):  
Urban Areas ◽  
Urban Expansion ◽  
Habitat Type ◽  
Nesting Success ◽  
Arid Environments ◽  
Hatch Date ◽  
Urban Density ◽  
Landscape Characteristics ◽  
Suburban Areas ◽  
Breeding Seasons

Abstract Despite the unique threats to wildlife in urban areas, many raptors have established successfully reproducing urban populations. To identify variations in raptor breeding ecology within an urban area, we compared metrics of Red-tailed Hawk reproductive attempts to landscape characteristics in Reno and Sparks, NV, USA during the 2015 and 2016 breeding seasons. We used the Apparent Nesting Success and logistic exposure methods to measure nesting success of the Red-tailed Hawks. We used generalized linear models to relate nesting success and fledge rate to habitat type, productivity to hatch date (Julian day) and hatch date to urban density. Nesting success was 86% and 83% for the respective years. Nesting success increased in grassland-agricultural and shrub habitats and decreased in riparian habitat within the urban landscape. Productivity was 2.23 and 2.03 per nest for the breeding seasons. Fledge rates were 72% and 77%, respectively, and decreased in riparian areas. Nestlings hatched earlier with increased urban density and earliest in suburban areas, following a negative quadratic curve. Nesting success and productivity for this population were high relative to others in North America. Productivity increased in habitats where ground prey was more accessible. We suggest that suburban areas, if not frequently disturbed, provide sufficient resources to sustain Red-tailed Hawks over extended periods. As urban expansion continues in arid environments globally, we stress that researchers monitor reproductive output across the urban predator guild to elucidate patterns in population dynamics and adaptation.

scholarly journals The Influence of Urban Sprawl on Air Pollution and the Mediating Effect of Vehicle Ownership

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1261
Author(s):  
Aiping Tao ◽  
Qun Liang ◽  
Peng Kuai ◽  
Tao Ding
Keyword(s):  
Air Pollution ◽  
Urban Sprawl ◽  
Negative Impact ◽  
Empirical Support ◽  
Mediating Effect ◽  
Vehicle Ownership ◽  
Mediating Role ◽  
Effect Model ◽  
Significant Negative Impact ◽  
The Impact

Based on the panel data of 224 prefecture-level and above cities in China from 2003 to 2016, this paper empirically studies the impact of urban sprawl on air pollution and introduces a mediating effect model to test the mediating role of vehicle ownership concerning the impact of urban sprawl on air pollution. The research in this paper arrives at three conclusions. First, urban sprawl has a significant positive effect on air pollution, and this conclusion is still valid after solving the endogeneity problem and conducting a robustness test. Second, the results of mediating effect test show that urban sprawl indirectly affects air pollution through the partial mediating effect of vehicle ownership. By removing the mediating effect, urban sprawl has a significant negative impact on air pollution, indicating that the mediating effect of vehicle ownership is higher concerning the impact of urban sprawl on air pollution. Third, further panel quantile regression results show that the higher the level of air pollution, the weaker the mediating effect of vehicle ownership and the stronger the direct effect of urban sprawl on air pollution. These conclusions can provide some empirical support for solving the air pollution problems caused by urban sprawl in China.

scholarly journals Mapping 20 Years of Urban Expansion in 45 Urban Areas of Sub-Saharan Africa

2021 ◽  
Vol 13 (3) ◽  
pp. 525
Author(s):  
Yann Forget ◽  
Michal Shimoni ◽  
Marius Gilbert ◽  
Catherine Linard
Keyword(s):  
Case Studies ◽  
Urban Areas ◽  
Urban Expansion ◽  
Local Population ◽  
Sub Saharan Africa ◽  
Annual Growth Rate ◽  
Urban Dynamics ◽  
Mapping Approach ◽  
Sub Saharan ◽  
The Impact

By 2050, half of the net increase in the world’s population is expected to reside in sub-Saharan Africa (SSA), driving high urbanization rates and drastic land cover changes. However, the data-scarce environment of SSA limits our understanding of the urban dynamics in the region. In this context, Earth Observation (EO) is an opportunity to gather accurate and up-to-date spatial information on urban extents. During the last decade, the adoption of open-access policies by major EO programs (CBERS, Landsat, Sentinel) has allowed the production of several global high resolution (10–30 m) maps of human settlements. However, mapping accuracies in SSA are usually lower, limited by the lack of reference datasets to support the training and the validation of the classification models. Here we propose a mapping approach based on multi-sensor satellite imagery (Landsat, Sentinel-1, Envisat, ERS) and volunteered geographic information (OpenStreetMap) to solve the challenges of urban remote sensing in SSA. The proposed mapping approach is assessed in 17 case studies for an average F1-score of 0.93, and applied in 45 urban areas of SSA to produce a dataset of urban expansion from 1995 to 2015. Across the case studies, built-up areas averaged a compound annual growth rate of 5.5% between 1995 and 2015. The comparison with local population dynamics reveals the heterogeneity of urban dynamics in SSA. Overall, population densities in built-up areas are decreasing. However, the impact of population growth on urban expansion differs depending on the size of the urban area and its income class.

scholarly journals Assessing the Impact of Urban Expansion on Surrounding Forested Landscape Connectivity across Space and Time

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 359
Author(s):  
Zhouqiao Ren ◽  
Jianhua He ◽  
Qiaobing Yue
Keyword(s):  
Landscape Connectivity ◽  
Urban Expansion ◽  
Landscape Fragmentation ◽  
Sustainable Urban Development ◽  
Delayed Response ◽  
Conservation Practices ◽  
Rapid Urbanization ◽  
Dynamic Landscapes ◽  
The Impact ◽  
Over Time

Landscape connectivity is important for all organisms as it directly affects population dynamics. Yet, rapid urbanization has caused serious landscape fragmentation, which is the primary contributor of species extinctions worldwide. Previous studies have mostly used spatial snap-shots to evaluate the impact of urban expansion on landscape connectivity. However, the interactions among habitats over time in dynamic landscapes have been largely ignored. Here, we demonstrated that overlooking temporal connectivity can lead to the overestimation of the impact of urban expansion. How much greater the overestimation is depends on the amount of net habitat loss. Moreover, we showed that landscape connectivity may have a delayed response to urban expansion. Our analysis shifts the way to understand the ecological consequences of urban expansion. Our framework can guide sustainable urban development and can be inspiring to conservation practices under other contexts (e.g., climate change).

scholarly journals Ocean Acidification Amplifies the Olfactory Response to 2-Phenylethylamine: Altered Cue Reception as a Mechanistic Pathway?

2021 ◽  
Author(s):  
Paula Schirrmacher ◽  
Christina C. Roggatz ◽  
David M. Benoit ◽  
Jörg D. Hardege
Keyword(s):  
Climate Change ◽  
Ocean Acidification ◽  
Hermit Crabs ◽  
Ecological Interactions ◽  
Ecological Processes ◽  
Mechanistic Pathway ◽  
Sea Lampreys ◽  
Pagurus Bernhardus ◽  
Decreasing Ph ◽  
The Impact

AbstractWith carbon dioxide (CO2) levels rising dramatically, climate change threatens marine environments. Due to increasing CO2 concentrations in the ocean, pH levels are expected to drop by 0.4 units by the end of the century. There is an urgent need to understand the impact of ocean acidification on chemical-ecological processes. To date, the extent and mechanisms by which the decreasing ocean pH influences chemical communication are unclear. Combining behaviour assays with computational chemistry, we explore the function of the predator related cue 2-phenylethylamine (PEA) for hermit crabs (Pagurus bernhardus) in current and end-of-the-century oceanic pH. Living in intertidal environments, hermit crabs face large pH fluctuations in their current habitat in addition to climate-change related ocean acidification. We demonstrate that the dietary predator cue PEA for mammals and sea lampreys is an attractant for hermit crabs, with the potency of the cue increasing with decreasing pH levels. In order to explain this increased potency, we assess changes to PEA’s conformational and charge-related properties as one potential mechanistic pathway. Using quantum chemical calculations validated by NMR spectroscopy, we characterise the different protonation states of PEA in water. We show how protonation of PEA could affect receptor-ligand binding, using a possible model receptor for PEA (human TAAR1). Investigating potential mechanisms of pH-dependent effects on olfactory perception of PEA and the respective behavioural response, our study advances the understanding of how ocean acidification interferes with the sense of smell and thereby might impact essential ecological interactions in marine ecosystems.

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