Penerapan Buffer Analysis dalam bidang Teknik Sipil dan Lingkungan

Perkembangan teknologi GIS menyediakan konsep, alat, dan analisis yangmendukung kebutuhan teknik sipil dan lingkungan. Tulisan ini membahas secarasingkat konsep buffer analysis/multiple ring buffer analysis pada platform GIS dalamaplikasi teknik sipil dan lingkungan. Tulisan ini menjelaskan penelitian-penelitiansebelumnya yang menerapkan buffer analysis/multiple ring buffer analysis. Bufferanalysis/multiple ring buffer analysis digunakan untuk mengetahui area layanan (halte bus, shelter untuk bencana), yang umum digunakan dalam teknik sipil; dan untuk memahami area dampak (perletakan TPA, kebisingan), yang umum digunakan dalam bidang teknik sipil dan lingkungan. Tulisan ini menyebutkan keterbatasan buffer analysis/multiple ring buffer analysis yang hanya berfokus pada variabel jarak.

Spatial equity in the layout of urban public sports facilities in Hangzhou

This paper proposes a framework for a layout evaluation of urban public sports facilities. First, the buffer analysis method is used to measure the service level of public sports facilities. The study findings indicate that the overall service level of public sports facilities presents the spatial characteristics of a central agglomeration, and the value of the service level diffuses outward from high to low. There is evident spatial heterogeneity in the layout of public sports facilities in Hangzhou. Second, the Gini coefficient, Lorenz curve, and location entropy are employed to measure the equity of the distribution among spatial units and the intradistrict disparity. The results show a mismatch between the spatial distribution of the facilities and the distribution of the permanent population. The patterns of distribution of the location entropy classes of Hangzhou can be divided into three types: balanced, alternating, and divergent districts. The method in this paper is effective in measuring spatial equity and visualizing it. it has a certain degree of systemicity, universality and operability. At the same time, this method can compare the diachronic characteristics of the same city and the synchronic characteristics of different cities, which has universal application value.

Optimization of Green Space Planning to Improve Ecosystem Services Efficiency: The Case of Chongqing Urban Areas

This paper applied landscape indexes to evaluate the size, form, and structure of green spaces in the mountainous city of Chongqing and found that green spaces benefit from certain advantages in size, but the network suffered from low heterogeneity and limited interconnectivity. To ensure the integrity and continuity of ecological processes and improve the efficiency of ecosystem services (ES), the authors used Geographic Information System (GIS) software to conduct adaptability evaluation and adjacent buffer analysis for the existing green spaces, wetlands, rivers, and other landscapes with relatively high capacity for ES. We designed a comprehensive map of potential areas for UGS expansion by superimposing the maps obtained from adaptability evaluation and buffer analysis. We also proposed some strategies that respect, consider, and evaluate aspects and special features of urban environment to optimize green space planning and improve ES efficiency, such as protection of important areas, development of green corridors, and careful consideration of ecological processes and complex functions in urban areas. Based on these strategies, the paper put forth suggestions for green space planning to improve ES efficiency that can function as foundation for subsequent green space planning.

How to Measure the Urban Park Cooling Island? A Perspective of Absolute and Relative Indicators Using Remote Sensing and Buffer Analysis

Urban parks have been proven to cool the surrounding environment, and can thus mitigate the urban heat island to an extent by forming a park cooling island. However, a comprehensive understanding of the mechanism of park cooling islands is still required. Therefore, we studied 32 urban parks in Jinan, China and proposed absolute and relative indicators to depict the detailed features of the park cooling island. High-spatial-resolution GF-2 images were used to obtain the land cover of parks, and Landsat 8 TIR images were used to examine the thermal environment by applying buffer analysis. Linear statistical models were developed to explore the relationships between park characteristics and the park cooling island. The results showed that the average land surface temperature (LST) of urban parks was approximately 3.6 °C lower than that of the study area, with the largest temperature difference of 7.84 °C occurring during summer daytime, while the average park cooling area was approximately 120.68 ha. The park cooling island could be classified into four categories—regular, declined, increased, and others—based on the changing features of the surrounding LSTs. Park area (PA), park perimeter (PP), water area proportion (WAP), and park shape index (PSI) were significantly negatively correlated with the park LST. We also found that WAP, PP, and greenness (characterized by the normalized difference vegetation index (NDVI)) were three important factors that determined the park cooling island. However, the relationship between PA and the park cooling island was complex, as the results indicated that only parks larger than a threshold size (20 ha in our study) would provide a larger cooling effect with the increase in park size. In this case, increasing the NDVI of the parks by planting more vegetation would be a more sustainable and effective solution to form a stronger park cooling island.

A Three-Dimensional Buffer Analysis Method Based on the 3D Discrete Global Grid System

Three-dimensional (3D) buffer analysis is among the basic functions of 3D spatial analysis, and it plays an important role in 3D geographic information systems. The rapid development of the 3D Discrete Global Grid System (DGGS) provides a new method for the 3D spatial analysis of geographic information. According to the spatial topology characteristics of the 3D DGGS and the concept of dimensionality reduction, a 3D buffer analysis method based on the spatial grid of the Earth system is proposed to solve the problem of the buffer algorithm of a space object being unsatisfactory at present. In this paper, we present a method to calculate the distance between cells based on the side length of the spherical grids according to the geometric characteristics of the grids. For the grids of a geographic object, we describe the Euclidean distance expansion algorithm and the radial elevation expansion algorithm that helped us to obtain its 3D buffer. Finally, in terms of algorithm complexity and visualization effect, compared with the traditional raster buffer algorithm, the method presented in this paper has lower complexity, an improved visualization effect, and stronger generality.

Human | Wildlife, Stitching The Fabric : Connectivity Strategies For Identified Gaps in Toronto's Ravines

This Master’s Research Project (MRP) examines landscape connectivity strategies for the ravine system in the City of Toronto, CA. A workshop with natural environment specialists from the City of Toronto was organized to gather practitioner-based information as to which gaps should be prioritized in the ravine system. This GAP Analysis was complemented with a Geographic Information System (GIS) - based buffer analysis looking at connectable green spaces in close proximity to Environmentally Significant Areas (ESAs). Based on both the workshop and GIS analysis, 16 gaps were investigated through which 4 typologies were created. Interviews were then conducted with professionals from comparator cities: Edmonton (CA), Vancouver (CA), Minneapolis (US), Copenhagen (DK), and Stockholm (SW) to compare into how waterfront cities use policies, partnerships and design interventions to connect waterfront public lands. Based on interviews and additional policy scans, connectivity strategies were created for all 4 typologies as a means to improve landscape connectivity in the City of Toronto.

Human | Wildlife, Stitching The Fabric : Connectivity Strategies For Identified Gaps in Toronto's Ravines

This Master’s Research Project (MRP) examines landscape connectivity strategies for the ravine system in the City of Toronto, CA. A workshop with natural environment specialists from the City of Toronto was organized to gather practitioner-based information as to which gaps should be prioritized in the ravine system. This GAP Analysis was complemented with a Geographic Information System (GIS) - based buffer analysis looking at connectable green spaces in close proximity to Environmentally Significant Areas (ESAs). Based on both the workshop and GIS analysis, 16 gaps were investigated through which 4 typologies were created. Interviews were then conducted with professionals from comparator cities: Edmonton (CA), Vancouver (CA), Minneapolis (US), Copenhagen (DK), and Stockholm (SW) to compare into how waterfront cities use policies, partnerships and design interventions to connect waterfront public lands. Based on interviews and additional policy scans, connectivity strategies were created for all 4 typologies as a means to improve landscape connectivity in the City of Toronto.

ANÁLISE DOS FOCOS DE CALOR EM DIFERENTES FAIXAS DE ÁREAS DE INFLUÊNCIA DA RODOVIA BR-242, NOVA UBIRATÃ-MT

A concentração dos focos de calor em diferentes faixas limítrofes de influência da rodovia BR-242 foi analisada no município de Nova Ubiratã-MT. Os focos de calor obtidos pelo banco de dados de Queimadas do Instituto Nacional de Pesquisas Espaciais (INPE), detectados pelo sensor MODIS do satélite AQUA foram identificados e quantificados. O estimador de densidade de Kernel e a análise de Buffer (distância em duas classes de 0 – 5 km e 0 – 20 km ao longo da BR-242) foram utilizados para estimar a distribuição dos focos de calor no município. Os resultados indicaram um aumento nos focos de calor a partir da área de influência de 20 km, constatando que 10% dos focos ocorreram na faixa de 0 – 5 km e 29% na faixa de 0 – 20 km, totalizando 5.568 focos detectados nos anos 2008 a 2017. Esta nova informação visa fomentar políticas públicas sobre os procedimentos aplicados pelo IBAMA na regularização ambiental das rodovias federais, especialmente para diagnosticar o passivo ambiental rodoviário. Palavras-chave: Sistema de Informação Geográfica; incêndios florestais; infraestrutura; monitoramento por satélite. Analysis of heat sources in different areas of influence of the BR-242 highway in the Nova Ubiratã-MT, Brazil ABSTRACT: The concentration of heat sources in different boundary bands of influence of the BR-242 highway was analyzed in the municipality of Nova Ubiratã-MT. The heat sources obtained by the database of burnings from Brazilian National Institute for Space Research (INPE), detected by the MODIS sensor of the AQUA satellite were identified and quantified. The Kernel density estimator and the Buffer analysis (distance in two classes of 0 - 5 km and 0 - 20 km along the BR-242 corridor) were used to estimate the distribution of heat sources in the municipality. The results indicated an increase in the heat sources from the area of ​​influence of 20 km, noting that 10% of the heat sources occurred in the range of 0 - 5 km and 29% in the range of 0 - 20 km, totaling 5,568 detected heat sources in the years from 2008 to 2017. This new information promises to promote public policies on the procedures applied by IBAMA in the environmental regularization of federal highways, especially to diagnose environmental road liabilities. Keywords: Geographic Information Systems; wildfire; infrastructure; satellite monitoring.