Introduction

Green spaces in cities, such as parks, allotments, cemeteries, and wastelands, are important components of green infrastructure (EC – European Commission 2013) and provide habitats for numerous animal and plant species (Cornelis and Hermy 2004; Angold et al. 2006). Over the last decades, many studies have shown high species richness and abundance in urban green spaces. This has particularly been the case for studies on birds (e.g. Husté and Boulinier 2007; Carbó-Ramírez and Zuria 2011) and plants (e.g. Fischer et al. 2013; Matthies et al. 2013), but also for other taxa such as mammals (e.g. Garden et al. 2007), butterflies (e.g. Snep et al. 2011), and carabid beetles (e.g. Knapp et al. 2008). These relationships have been found in several cities in Europe (e.g. Bräuniger et al. 2010; Fischer et al. 2013), Asia (e.g. Saito and Koike 2013; Koh and Sodhi 2004), and North America (e.g. Oliver et al. 2011; Turner et al. 2005). In order to clarify the relevance of urban green spaces for nature conservation it is, in addition to total species richness, valuable to assess the number of endangered and native species (e.g. Pyšek et al. 2004). The richness of plant and animal species in urban green spaces has often been studied in relation to alien species (McKinney 2006; La Sorte et al. 2014). For instance, Pyšek et al. (2004) found that green spaces support a large number of non-native plant species in the city of Plzen, Czech Republic. DeCandido (2004) documented a decline in plant species richness in a park in New York City from 1947 to 1994, which was partly due to increasing numbers of exotics. High numbers of non-native species have also been documented for birds (e.g. Shwartz et al. 2008; Platt and Lill 2006) and selected invertebrates (e.g. Tonietto et al. 2011; Vilisics and Hornung 2009). Therefore, it has often been argued that high species numbers in urban green spaces are caused by high numbers of alien species (e.g. McKinney and Lockwood 2001). Nevertheless, a variety of other studies found evidence that also native species (Wania et al. 2006; Kühn et al. 2004) and endangered species (Meffert and Dziock 2012; Matthies et al. 2015) reach high species numbers in urban green spaces. These findings consistently show that different species groups within taxonomic groups contribute to the species richness in urban green spaces (cf. McKinney 2008). Urban green spaces can be seen as habitat islands within the urban matrix. A key finding of the urban habitat island approach is that green spaces show patterns of species-area relationships as observed in island biogeography (e.g. MacGregor-Fors et al. 2011). The species-area effect explains how larger areas usually facilitate greater species richness (MacArthur and Wilson 1967). For urban green spaces, an increasing number of species with increasing patch areas has been shown for vascular plants (Angold et al. 2006; Li et al. 2006), birds (van Heezik et al. 2013; Carbó-Ramírez and Zuria 2011; Chamberlain et al. 2007; Husté et al. 2006), and mammals (Hodgkison et al. 2007). In contrast, no significant species-area relationships have been found for butterflies and carabid beetles in urban green spaces (Bräuninger et al. 2010; Lizée et al. 2016).

With the acceleration of the urbanization process in Beijing, the demand for urban land is increasing; as a result, a considerable amount of pressure has been placed on expanding green spaces, which fulfll an ecological function for the public. At the end of 2015, the resident population of Beijing was 21.75 million and the resident urbanization rate was 86.5% (Beijing Municipal Bureau of Statistics 2016). These fgures show that there is a large demand in the city for urban green spaces and its related ecosystem services (e.g., provisioning services, regulating services, and cultural services). However, industrialization, urbanization, and increases in the resident population exacerbate urban environmental problems. In 2016, the number of days during which Beijing’s air quality failed to meet a safe standard amounted to 167; further, current levels of NO2, PM10, and PM2.5 all surpass national standards, particularly the annual average concentration of PM2.5, which is currently in excess of 109% of the national standard and has reached 73 μg/m3 (Beijing Municipal Environment Protection Bureau 2017). Since the material and cultural needs of Beijing residents can be considered as having been met, the demand that Beijing’s environmental issues be addressed is increasing, as the present environmental conditions are far from satisfactory. Air pollution and environmental disasters have a negative infuence on residents’ well-being (Ferreira et al. 2013); smog is particularly damaging in this regard, as it brings serious health problems and huge social health costs (Cao and Han 2015). Data show that in 2014–2016, the average annual dust-retention rate of Beijing’s garden greening initiative was approximately 9800 tons, of which fne dust accounted for 100 tons and coarse particulate matter approximately 1200 tons; the remaining dust equated to approximately 8500 tons, which is equal to an extra 15 days of second-level air quality (Tie and Lun 2017). In order to continue to address this problem, the Beijing municipal government has increased the construction of green landscaping. The total size of urban green spaces has increased annually, reaching 82,122 ha, which is equal to more than the area of 10,000 football felds, and in the future, more land will be allocated for the construction of urban green spaces. In addition, the per capita park area of Beijing has reached 16.1 m2 , the urban green spaces coverage rate (ratio of total area of green space in cities to total land area in cities) has reached 48.1%, the forest greening rate is 59.3%, and the forest coverage rate is 42.3%. As these rates continue to increase, the living environment further improves. The Beijing Municipal Bureau of Landscape and Forestry is responsible for the construction of urban green spaces. The Beijing Municipal Government pays close attention to the construction of green spaces, and eforts to expand the green space in Beijing have become the focus of their work. In 2016, the total amount of funds dedicated to landscape and forestry has reached 16 billion yuan1 (Beijing Municipal Bureau of Landscape and Forestry 2017). Urban green spaces include city and country parks, botanical gardens, zoos, cemeteries, small gardens, and street and square green spaces. In this study, we mainly considered city and country parks and community or square green spaces.

Due to rapid urbanization in developing world, city administrators and urban planners are challenged with problems in delivering basic services like green space, sanitation, water supply, transportation, and primary health center. The urban green spaces’ coverage is not adequate to meet people’s needs due to population pressure, expansion of industry, and construction in the process of urbanization (Cetin 2015a, b, c). Urban planners have to visualize such growth during planning, policy, and decision-making. Impulsive construction of unplanned informal houses in and outside the administrative boundaries of towns and cities is common in developing countries. These insightful changes cause a change in land use type which makes urban planning foreseeable (Zewdu 2011). Urban planning does not only cover matters of the built environment such as housing and transportation network, but also the integration of green spaces into the physical urban landscape. The main indicators of planned urbanization expecting physical and socioeconomic development in terms of the suitable areas for health, where bioclimatic comfort arises as one of the most significant factors (Cetin 2015a, b, c). The bioclimatic comfort situations can be established with the design criteria of landscape architecture and planning (Cetin et al. 2016). In recent years, Addis Ababa and its surroundings have observed unprecedented land degradation as a consequence of deforestation for firewood supply and human settlement. Big tracts of the city’s vegetation area are transformed to permanent structures at a rate of 6.65 km2 /year (Tamiru et al. 2005). About 10,000 ha of land initially reserved for green spaces have been allocated for other uses (Tadesse 2010). Over the years, Addis Ababa witnessed ecosystem degradation and vegetation cover is estimated at 14.6% (AAEPA 2005). In the city, 382 ha of riparian area is being cultivated by vegetable growing farmers, which cover up to 7.1% of the city’s vegetable demand (Azeb 2007). Land suitability analysis is the process to determine whether the land resource is appropriate for some specific uses and to determine the suitability level by considering different factors such as LULC (land use and land cover) type, landscape, and road infrastructure (Manlun 2003). Suitability analysis of different LULC patterns and dynamics is important to determine the most desirable site for future development. Identifying appropriate suitability parameters are the foundation of construction of suitability analysis. Green spaces are land uses that are covered with natural or man-made vegetation in the built-up areas and planning areas (Manlun 2003). The meaning of the green space system has also been continuously emerging with the development of city theory, which mainly encompasses horticultural, ecological, and spatial meanings. GIS has the main role in land-use suitability analysis for green space. In the tourism sector also, maps have vital role to protect natural and cultural value in terms of time and cost efficiency and deliver very accurate and up-to-date data (Cetin 2015a, b, c).