scholarly journals Urban Ecological Corridor Network Construction: An Integration of the Least Cost Path Model and the InVEST Model

2020 ◽  
Vol 9 (1) ◽  
pp. 33 ◽  
Author(s):  
Yuhan Tang ◽  
Chi Gao ◽  
Xuefei Wu

Under the background of urban expansion, ecological protection cannot be delayed. The construction of ecological networks is of considerable significance to ecosystem services. However, in the process of constructing a corridor network, there is no uniform standard for the selection of ecological sources and the determination of cost factors. The InVEST model is an effective complement to ecosystem service assessment for sensitively measuring external threats and their threat intensity. Therefore, taking Wuhan as an example, we combined InVEST and the least cost path model (LCP) to construct a multi-target corridor network with comprehensive cost factors for birds and small terrestrial mammals. The results showed that: (1) The InVEST model provided a reliable basis for ecological source screening by demonstrating the distribution of habitat quality. (2) The corridor with a length of 12–25 km presented a “U” shape, and the impact of urbanization on small terrestrial mammals was more significant than that of birds. (3) The integrated network pattern proposed by the “point-line-plane” principle would provide a reference for urban ecological construction and sustainable development.

Water Policy ◽  
2016 ◽  
Vol 19 (1) ◽  
pp. 181-195 ◽  
Author(s):  
Huiqing Han ◽  
Yuxiang Dong

Water supply is an important freshwater ecosystem service provided by ecosystems. Water shortages resulting from spatio-temporal heterogeneity of climate condition or human activities present serious problems in the Guizhou Province of southwest China. This study aimed to analyze the spatio-temporal changes of water supply service using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model, explore how climate and land-use changes impact water supply provision, and discuss the impact of parameters associated with climate and land-use in the InVEST model on water supply in the region. We used data and the model to forecast trends for the year 2030 and found that water supply has been declining in the region at the watershed scale since 1990. Climate and land-use change played important roles in affecting the water supply. Water supply was overwhelmingly driven by the reference evapotranspiration and annual average precipitation, while the plant evapotranspiration coefficients for each land-use type had a relatively small effect. The method for sensitivity analysis developed in this study allowed exploration of the relative importance of parameters in the InVEST water yield model. The Grain-for-Green project, afforestation, and urban expansion control should be accelerated in this region to protect the water supply.


2018 ◽  
Vol 24 (1) ◽  
pp. 63 ◽  
Author(s):  
Elizabeth A. Brunton ◽  
Sanjeev K. Srivastava ◽  
David S. Schoeman ◽  
Scott Burnett

Human population growth and the resultant expansion of urban landscapes are drivers of biodiversity loss globally. Impacts of urbanisation on wildlife are not well understood, although the importance of preserving biodiversity in urban areas is widely recognised. The eastern grey kangaroo (Macropus giganteus), a common species of large macropod, can be found in high densities in many urban landscapes across Australia. South East Queensland is a subtropical region of Australia that has experienced high rates of urban expansion. Human population growth in the region has resulted in widespread changes to the landscape and much of the eastern grey kangaroo’s natural habitat has been modified. Declines in kangaroo populations have been anecdotally reported; however, the impact of urbanisation on kangaroo populations has not been quantified. This study used a modelling approach, collecting data from the community, and private and government organisations to: (1) map the current distribution of eastern grey kangaroos; (2) quantify trends in kangaroo abundance; and (3) identify anthropogenic drivers of changes in kangaroo abundance in the region. Of the kangaroo populations identified, 42% were reported to have undergone an overall decline in abundance since 2000. Higher human population growth rate and smaller area remaining under natural land use were predictors of kangaroo population declines. Further kangaroo declines can be anticipated in the region, particularly in areas with projected human population growth rates over 80% for the next decade. This study emphasises the importance of integrated urban development over large spatial extents to mitigate impacts of urbanisation on terrestrial mammals.


2020 ◽  
Author(s):  
Joseph Lewis

Despite the methodological issues of Least Cost Path analysis being well known, the inclusion of traversal across slope has not been assessed. This paper uses a Roman road built along a ridge in Cumbria, England as a case study. The ‘High Street’ Roman road provides a suitable case study as its route along the ridge is dictated by the topography. By comparing the computed Least Cost Path results when including and not including traversal across slope as a cost component, this research has found that the inclusion results in Least Cost Paths that more accurately model the known route of the Roman road along the ridge. The Least Cost Path model when not including traversal across slope resulted in 84.8% of the Least Cost Path being within 600m of the known route, compared to 100% when including traversal across slope. Due to the application of anisotropic cost functions, this research also identified that both Least Cost Path models predicted the route from the south towards the north frontiers more accurately, suggesting the Roman road was built with this direction of movement in mind.


2019 ◽  
Vol 11 (1) ◽  
pp. 184 ◽  
Author(s):  
Xinli Ke ◽  
Liye Wang ◽  
Yanchun Ma ◽  
Kunpeng Pu ◽  
Ting Zhou ◽  
...  

Land use and land cover change is a critical factor of ecosystem services, while water yield plays a vital role in sustainable development. The impact of urban expansion on water yield has long been discussed, but water yield change resulting from cropland protection is seldom concerned. Therefore, this paper aims to investigate the impacts of cropland protection on water yield by comparing the water yield in two cropland protection scenarios (i.e., Strict Cropland Protection scenario and No Cropland Protection scenario). Specifically, the LAND System Cellular Automata for Potential Effects (LANDSCAPE) model was employed to simulate land use maps in the two scenarios, while Water Yield module in the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model was used to calculate water yield. The results show water yield would increase by 8.7 × 107 m3 in the No Cropland Protection scenario and 9.4 × 107 m3 in the Strict Cropland Protection scenario. We conclude that implementation of strict cropland protection in rapid urbanizing areas may cause more water yield, which is also a prerequisite of potential urban flooding risk. This study throws that it is not wise to implement strict cropland protection policy in an area of rapid urbanization.


2016 ◽  
Vol 16 (2) ◽  
Author(s):  
Roberta Montanheiro Paolino ◽  
Natalia Fraguas Versiani ◽  
Nielson Pasqualotto ◽  
Thiago Ferreira Rodrigues ◽  
Victor Gasperotto Krepschi ◽  
...  

Habitat loss and degradation is threatening mammals worldwide. Therefore, Protected Areas (PA) are of utmost importance to preserve biodiversity. Their effectiveness, however, depends on some management strategies such as buffer zones, which prevent/mitigate the impact of external threats and might increase the amount of available habitat for wildlife existing within reserves. Nevertheless, how intensively terrestrial mammals use buffer zones remains little studied, particularly in the Neotropical region. Aiming to analyse the use of a buffer zone (5 km wide) by medium and large-sized mammals, we modelled the occupancy probabilities of five species of conservation concern including local (interior and buffer zone) as a site covariate, simultaneously controlling for imperfect detection. Data collection was made with camera traps from April to September 2013 in a 9000 ha Cerrado PA (“interior”) and in its surrounding area (39721.41 ha; “buffer zone”). This PA (Jataí Ecological Station) is immersed in a landscape where sugarcane plantations predominate in the northeastern of the state of São Paulo. We also conducted an inventory to compare the number and composition of species between interior and buffer zone. A total of 31 mammal species (26 natives) was recorded via camera traps and active search for sightings, vocalizations, tracks and signs. Occupancy estimates for Myrmecophaga tridactyla, Leopardus pardalis and Pecari tajacu were numerically higher in interior. On the other hand, Chrysocyon brachyurus had the highest occupancy in buffer zone, while the largest predator, Puma concolor, used both areas similarly. However, as the confidence intervals (95%) overlapped, the differences in occupancy probabilities between interior and buffer were weak for all these species. Additionally, regarding only the species recorded by cameras, the observed and estimated richness were similar between interior and buffer zone of the PA. Our data demonstrated that the buffer zone is indeed used by medium and large-sized mammals, including conservation-dependent ones. The lack of enforcement of current legislation regarding buffer zones is therefore a real threat for mammals, even when protection is guaranteed in the interior of protected areas.


Sains Insani ◽  
2018 ◽  
Vol 2 (1) ◽  
pp. 17-27
Author(s):  
Megat Ayop Megat Arifin ◽  
Abd. Halim Ahmad

Whitsleblowing is one of the positive practices in organizations that are able to raise the level of integrity among the members of an organization. However, the roles of whistleblowing also inevitably invites a response, especially among members of the organization itself. This is because such practices are viewed as one factor that may be detrimental to the organization in addition to revealing the reporter (whistleblower) to some external threats and intimidation of discrimination within the organization. This paper is an attempt to examine the relationship between perceptions of members of the Royal Malaysian Police (RMP) Contingent of Perak through the role of whistleblowing practices to increase the perception of the integrity of the members. Next, identify the purpose of the whistleblowing and its effect on the integrity of the members of the organization. This study used a descriptive quantitative analysis to identify patterns of relationship that exists between the perception of whistleblowing practices with perceptions of increased integrity based on three basic variables of demographic factors, response to whistleblowing and the impact of making the report. The results showed that members of the Perak’s police have a positive perception of whistleblowing practices which are seen to be done in improving the integrity of the members.Keywords: whistleblowing, perception, RMP members, culture, integrity, organization, influence. ABSTRAK: Whitsleblowing merupakan salah satu amalan positif dalam organisasi yang mampu untuk meningkatkan tahap integriti ahli-ahli dalam sesebuah organisasi. Namun begitu, amalan whistleblowing juga turut tidak dapat mengelak daripada mengundang pelbagai respon khususnya dalam kalangan ahli organisasi itu sendiri. Amalan sebegini turut dilihat sebagai salah satu faktor yang boleh memudaratkan organisasi di samping mendedahkan pelapor (whistleblower) kepada beberapa bentuk ancaman ugutan dari luar dan diskriminasi dalam organisasi. Kertas ini merupakan satu upaya untuk melihat perkaitan antara persepsi anggota Polis Diraja Malaysia (PDRM) Kontinjen Perak melalui peranan amalan whistleblowing terhadap persepsi peningkatan integriti anggota. Seterusnya, mengenalpasti maksud whistleblowing dan pengaruhnya terhadap tahap integriti anggota dalam organisasi. Kajian ini menggunakan analisis kuantitatif berbentuk deskriptif bagi mengenalpasti corak hubungan yang wujud antara persepsi terhadap amalan whistleblowing dengan persepsi terhadap peningkatan integriti berdasarkan tiga pembolehubah asas iaitu faktor demografi, tanggapan terhadap whistleblowing dan kesan daripada tindakan membuat laporan. Dapatan kajian menunjukkan bahawa anggota PDRM Perak mempunyai persepsi yang positif terhadap whistleblowing yang mana ianya dilihat perlu dilaksanakan dalam meningkatkan integriti anggota.Kata kunci: whistleblowing, persepsi, amalan, anggota PDRM, budaya, integriti, organisasi, pengaruh.  


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 ◽  
...  

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.


2019 ◽  
Vol 25 (40) ◽  
pp. 5503-5511 ◽  
Author(s):  
Abdulaziz Alhasaniah ◽  
Michael J. Sherratt ◽  
Catherine A. O'Neill

A competent epidermal barrier is crucial for terrestrial mammals. This barrier must keep in water and prevent entry of noxious stimuli. Most importantly, the epidermis must also be a barrier to ultraviolet radiation (UVR) from the sunlight. Currently, the effects of ultraviolet radiation on epidermal barrier function are poorly understood. However, studies in mice and more limited work in humans suggest that the epidermal barrier becomes more permeable, as measured by increased transepidermal water loss, in response UVR, at doses sufficiently high to induce erythema. The mechanisms may include disturbance in the organisation of lipids in the stratum corneum (the outermost layer of the epidermis) and reduction in tight junction function in the granular layer (the first living layer of the skin). By contrast, suberythemal doses of UVR appear to have positive effects on epidermal barrier function. Topical sunscreens have direct and indirect protective effects on the barrier through their ability to block UV and also due to their moisturising or occlusive effects, which trap water in the skin, respectively. Some topical agents such as specific botanical extracts have been shown to prevent the loss of water associated with high doses of UVR. In this review, we discuss the current literature and suggest that the biology of UVR-induced barrier dysfunction, and the use of topical products to protect the barrier, are areas worthy of further investigation.


Land ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 762
Author(s):  
Lei Han ◽  
Rui Chen ◽  
Zhao Liu ◽  
Shanshan Chang ◽  
Yonghua Zhao ◽  
...  

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.


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