INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 4, No 3, 2014

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1 INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 4, No 3, 2014 Copyright 2014 All rights reserved Integrated Publishing services Research article ISSN Quantitative evaluation of distribution and accessibility of urban green spaces (Case study: City of 1,2 1-Civil Engineering Department., Faculty of Engineering, Assiut University, Assiut, Egypt 2- Landscape Architecture Dept., Faculty of Environmental Design, KAU, Saudi Arabia ABSTRACT Urban green spaces are quite significant in reducing negative effects of urbanization. They are viewed as the green lung of the city, and typically perform important functions, including absorbing rainwater and pollutants, and mitigating urban heat. Urban green spaces can also provide considerable socioeconomic benefits, such reducing work-related stress, and increasing property values. Green space is becoming an important measure in judging the ecological sustainability of urban areas. Planners and designers need efficient tools to quantitatively evaluate and compare the impact of alternative plans and designs so that more informed development choices could be made. This study presents an evaluation of spatial equity in distribution of green spaces in Jeddah city using Geographic Information System (GIS). GIS analysis is used to study the spatial distribution of needs and accessibility. The results of this study show that the average green space per capita is 0.9 m 2 and more that 70% of population have to walk distance exceed 500 m to reach green space. In order to reach green space equal to 30 m 2 per capita which is the standard of united nation it s needed to meet lack of urban green space about 93,808,406 m 2 in Jeddah city. Keywords: Urban green spaces; accessibility; per capita; GIS analysis. 1. Introduction Green spaces and parks are of great importance both for ecological balance and for the health of individuals (Al-Ballaa et al 2010; Paquet et al 2013). They are quite significant in reducing negative effects of urbanization and increase physical activity of people (Hillsdon et al 2006; Mytton et al 2012). Urban green spaces are viewed as the green lung of the city, and typically perform important functions, including absorbing rainwater and pollutants, and mitigating urban heat. They can also provide considerable socioeconomic benefits, such socializing and rest and restitution (Peschardt et al 2012; Rahnama and Akbari 2013), and increasing property values (lin et al 2013). Green space is becoming an important measure in judging the environmental quality and ecological sustainability of urban areas (Gupta et al 2012). Laghai and Bahmanpour (2012) summarized more than 30 function and services of urban green spaces. Proximity to the green space affects the purpose and frequency of visiting the place. The social role of green spaces is affected by its optimal distribution (Chiari and Seeland 2004). The European Environment Agency (EEA) recommends that people should have access to green space within 15 min walking distance, while English Nature (EN), a UK government agency, recommends that distance to green space should not exceed 300m from home (Barbosa et al 2007). Toftager et al (2011) found that persons living more than 1 km from Submitted on December 2013 published on March

2 green space had lower odds of using green space to exercise and keep in shape compared with persons living closer than 300 m to green space. One of the green city index indicators is per capita space. Decreasing in per capita urban green space causes a decrease in daily exposure to more natural environments (Barton and Pretty, 2010). Lower exposure to natural environments is associated with a number of lifestyle diseases such as obesity, diabetes II, osteoporosis and stress-related illnesses such as depression, heart diseases and mental fatigue (Ulrich, 2006; Mitchell and Popham, 2008). The aim of this study is to evaluate the equity of the distribution of public green spaces and their accessibility using GIS analysis and to figure out if the amount of green space in Jeddah matches the international standards. 2. Study area and data Jeddah is a city in the Hijaz region on the coast of the Red Sea and is the major urban center of western Saudi Arabia. It is the largest city in Makkah Province, the largest sea port on the Red Sea, the second-largest city and an important commercial hub in Saudi Arabia. It is located between (21 15 N, N) and (39 5 E, E) as shown in figure (1). It has a population of according to (Central Department of Statistics & Information 2010). The data used in this study was collected from Jeddah Municipality. It contains Road, Districts and Urban green space layers and districts population statistical data. The total number of Jeddah population according to 2010 statistics was gotten from the Central Department of Statistics and Information web page. 3. Methodology Figure 1: The location of study area In the analysis of the distribution of green spaces in Jeddah, the next steps were followed: 527

3 1. Data collection consulting specific literature, connecting Jeddah Municipality for getting districts, urban green spaces (some districts), roads and population statistical data; 2. Database creation districts population data Excel sheet was prepared to be linked to the districts layer. The district names were verified to match that of the districts layer. Digitization of green spaces based on Bing map online available with ArcGIS 10 software; 3. Data processing using GIS models and techniques completed by statistical analysis; 4. Interpretation of the results obtaining graphs and cartographic materials using GIS techniques. The following indices have been used for the assessment of the distribution of green spaces: 1. Green space per capita (m 2 ), the results of Jeddah was compared to the international standards such as United Nations (30 m 2 per capita) (Laghai and Bahmanpour 2012), European Union standards (26 m 2 per capita) (Vlad and Brătăşanu 2011), public health bureau and the ministry of housing of the united states of America (18 m 2 per capita) (Laghai and Bahmanpour 2012) and World Health Organization standards (9 m 2 per capita) (Saz.S.D and Rausell P. 2008). 2. accessibility to green spaces, measured by the percentage of the total population of the districts living in less than 300 m, 500 m and 15 minutes walking distance ( 1000 m) from urban green areas. 4. Data processing and results Jeddah has 119 districts according to the Municipality new divisions, 72 of them have population data. The population data was for year 2002 with expectations for year The expected population was used in this study and was shown in figure (2) after excluding airport, seaport, naval base and the university campus. The percentage of green spaces to each district area was calculated and presented graphically in figure (3). Table (1) summarizes the percentage of green spaces related to the districts area. From figure (3) and table (1), it is clear that almost half of Jeddah districts have green space less than 0.1% of district area. Only 10% of districts have green spaces equal to 5% to 8% of its area. In order to get the information of green space per capita in Jeddah city the discussed layers including population size and amount of green space have been overlaid and shown in figure (4). The average green space per capita in Jeddah was calculated and found to be 0.9 m2. A comparison of Jeddah average per capita to the existing standards is shown in figure (5) which illustrates the great difference between Jeddah green space and the international standards. Jeddah municipality has to increase the amount of green spaces at least 10 times the existing situation to reach the minimum amount of standards. Based on existing data from public census expectations of population in year 2014 and the statistics of green space area in Districts of Jeddah city in the same year, the green space per capita has been calculated and the outcome was compared with the international standards as shown in table (2). Figure (6) shows the shortage in green spaces based on the world health organization standards. 528

4 Figure 2: Distribution of population in districts of Jeddah Figure 3: Percentage of green spaces in districts of Jeddah 529

5 Table 1: Percentage of green spaces in districts of Jeddah % Green space No. of districts % of Jeddah districts < 0.1% % % % % Figure 4: Green spaces per capita (m 2 ) in districts of Jeddah Figure 5: Comparison of Jeddah green space per capita with existing standards 530

6 Figure 6: The shortage in Jeddah green space based on 9 m 2 /capita standards. Table 2: Comparison of Jeddah green space per capita with existing standards Existing standards Descriptions Shortages (m 2 ) In this situation only (AL ANDULUS, AL AMEER FAWAZ AL SHAMALY and AL 26,413,151 m World Health Organization standards: 9 m 2 AMEER FAWAZ ALJANOUBY) Districts (10 times the /capita satisfy the standards and rest of the Districts existing) has shortage. Public health bureau and the ministry of housing of the USA: 18 m 2 /capita European Union standards:26 m 2 /capita United Nations standards:30 m 2 /capita In this situation only (AL ANDULUS) District satisfies the standards and rest of the Districts has shortage. 55,178,699 m 2 (20 times the existing) In this situation all Districts have shortage. 80,913,294 m 2 (29 times the existing) In this situation all Districts have shortage. 93,808,406 m 2 (33 times the existing) Accessibility is measured by the walking distance to the green space. The 15 minutes walking distance ( 1000 m) recommended by European Environment Agency (EEA) seems to be long distance in Jeddah weather conditions, while 300 m walking distance recommended by English Nature (EN) is appropriate. Buffer distances of 300, 500 and 1000 m are shown in figure (7). The covered area by each buffer zone was calculated and the percentage of residential area that can access to the green space is shown in figure (8). It can be seen in figure (8) that only 15% of residential area is located less than 300 m away from the nearest green space, while 27% are situated from the nearest green space at a distance of 500 m and 54% of residential area fall within 1 km of the nearest green space. The percentage of each 531

7 district area fall within 500 walking distance is represented in figure (9). From which it was found that only 7 districts which represent 10% of the study area have 70% of each area fall within 500 m to the green spaces. Figure 7: Accessibility to green spaces in districts of Jeddah Figure 8: The percentage of residential areas by the accessibility to green spaces 532

8 5. Conclusions Figure 9: Percentage of 500 m accessibility in districts of Jeddah Green space areas in the densely populated cities of today are valued more than before while at the same time are suffering shrinkage due to pressures for more lands for housing development. ArcGIS was used to analyze the distribution and accessibility of green spaces in Jeddah. From the results of analyzing the spatial distribution of green spaces the followings could be concluded: 1. More than 80% of Jeddah districts have green spaces of less than 1% of its area. 2. Only 10% of districts have green spaces of 5 to 8% of its area. 3. The average green space per capita is 0.9 m 2 which is far away below the minimum standards. 4. It's needed to establish green space with the area of 26,413,151 m 2 which is 10 times the existing green area to fulfill the World Health Organization standards. 5. To reach the United Nations standards, it's needed to establish green space with the area of 93,808,406 m 2 which is 33 times the existing green area. 6. More than 85% of Jeddah population has to walk distance longer than 300 m to reach the nearest green space. 7. More than 70% of Jeddah population has to walk distance longer than 500 m to reach the nearest green space. 8. Only 3 districts in Jeddah that 95% of their populations live within 500 m of green space. 9. Districts with high need for green spaces and low levels of accessibility are emphasized as critical areas that public decision makers need to focus on. 533

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