Urban land-cover change threatens biodiversity and affects ecosystem productivity through loss of habitat, biomass, and carbon storage. However, despite projections that world urban populations will increase to nearly 5 billion by 2030, little is known about future locations, magnitudes, and rates of urban expansion. Here we develop spatially explicit probabilistic forecasts of global urban land-cover change and explore the direct impacts on biodiversity hotspots and tropical carbon biomass. If current trends in population density continue and all areas with high probabilities of urban expansion undergo change, then by 2030, urban land cover will increase by 1.2 million km2, nearly tripling the global urban land area circa 2000. This increase would result in considerable loss of habitats in key biodiversity hotspots, with the highest rates of forecasted urban growth to take place in regions that were relatively undisturbed by urban development in 2000: the Eastern Afromontane, the Guinean Forests of West Africa, and the Western Ghats and Sri Lanka hotspots. Within the pan-tropics, loss in vegetation biomass from areas with high probability of urban expansion is estimated to be 1.38 PgC (0.05 PgC yr−1), equal to ∼5% of emissions from tropical deforestation and land-use change. Although urbanization is often considered a local issue, the aggregate global impacts of projected urban expansion will require significant policy changes to affect future growth trajectories to minimize global biodiversity and vegetation carbon losses.

https://www.pnas.org/content/pnas/109/40/16083.full.pdf

Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools

Global Forecasts of Urban Expansion to 2030 and Direct Impacts on Biodiversity and Carbon Pools

Urban sustainability and human health: an African perspective

1. INTRODUCTION In 2011, the world population reached 7 billion inhabitants, out of which approximately 10% lived in communities that exceeded 10 million people (Bremner, 2010). Estimates show that about half of the world population lives in urban areas. The high degree of urbanization has led to the necessity of creating as many oasis of peace and fresh air as possible, in order to increase the quality of recreational facilities (Obinna and all, 2009). Due to this fact, more and more attention has been paid to the urban green areas, especially because of their numerous functions, such as: maintaining the health as well as their amusement, social, aesthetic and ecological functions. Not to mention the fact that the green space has a considerable economic importance. Thus, from the ecological perspective, the urban green areas are a true moderator of the impact of human activities on the environment. They contribute to the physical and chemical cleansing of the atmosphere, to the diminishing of the phonic pollution as well as to the moderation of the urban climate. From a social point of view, the green areas, which are public areas, contribute to the increase of social inclusion, by creating opportunities for people of all ages to interact by either an informal social contact or by taking part in community events. These areas can also be great places for people to hold social or cultural events, such as local festivals, theatrical or cinematographic activities, etc. The green areas that are well preserved play a significant role in keeping the urban population healthy. They offer opportunities which encourage a more active lifestyle (walks, jogging, cycling, etc. including getting from the residential areas to different public facilities). Green areas also provide the ideal playground for children, thus contributing to their physical, mental and social development. The urban green space is highly important from an aesthetic point of view as well, because it diminishes the rigid perception of the buildings, which tend to take over the cities. Due to the value of the landscape arrangements, the green areas confer identity to the human settlements (Gondo and Zibabgwe, 2010). The positive impact of the green space expands to the economic sphere of the cities. A pleasant environment helps creating a favorable image of the urban centres, thus increasing their attractiveness to investors and the possibility of creating new work places. The presence of the green space determines the increase of the urban areas value and, implicitly, of that of the neighbouring properties. The well preserved green areas also contribute to a higher quality of life, due to the fact that people attribute more value to the neighbourhoods that have good green areas. According to Rabare, Okech and Onyango (2009), the quality of parks provides a quick and highly visible indicator of whether an area is an attractive place for people to live and for economic activities to thrive. In conclusion, green areas represent a necessity, especially when taking into consideration certain urban problems such as: the traffic jams, the pollution of the environment and the lack of space for socializing. However, the existence of vegetation and public parks is not enough to make a city adopt a durable model (German-Chiari and Seeland, 2004). There has been a growing interest in the urban green areas lately. They started as a decorative element in the cities, but have acquired a new value, the importance of which is welcomed by the entire world. This has required a constant evaluation of the quality of the green space in the cities. The assessment of their quality represents an essential point in any sustainable development. 2. LITERATURE REVIEW Literature abounds in studies referring to the quality of green space. In the following is presented a selection of the studies on this subject as well as their main ideas. Adamec, Banuelos and Bruse (2004) presented a series of important socio-economical problems that European cities have to face: the urban expansion, the traffic jams, the noise, the air pollution. …

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The Quality of Bucharest's Green Spaces

The rapid urban growth poses a huge challenge in sustaining the quality of local environment and life characteristics in contemporary cities. There is a growing body of literature on sustainable cities, QoL, livability; yet a transparent and verifiable knowledge on its assessment at the urban scale is both limited and disparate. Very recently, the use of computational models, tools and indices has seen a sudden upsurge in QoL assessment at the city and sub-city level. This research, through an exhaustive review of scientific and policy literature postulates that despite promulgation of numerous and comprehensive indices and tools, yet these demonstrate a great deal of inconsistency and incomparability. This necessitates an investigation into what ought to be the preferred attributes/features of an ideal model, thereby demanding a systematic, transparent and objective appraisal of urban QoL assessment tools used worldwide. Addressing to the above objective, the research examines peer-reviewed papers to derive eight fundamental study criteria (type of dataset, scope or parameters, sample- coverage and unit, approach, technique, model type, interphase and application) that could typically characterizes such tool. It then reviews scientific and policy literature, open-access webpages on the internet to identify a first of its kind, exhaustive inventory of 26 urban QoL models and then critically evaluates these on the basis of the eight study criteria. The ensuing results bring to the fore a plethora of new, interesting and some inconvenient findings, most importantly that not even a single tool captures all the seven theoretical dimensions of QoL. Despite meant to evaluate quality in cities, only few tools conduct qualitative, subjective, bottom-up, GIS based simulation modeling that could effectively be put to use for more public and policy oriented applications. Lastly, the research demonstrates with credible evidence that a majority of tools/index continue to understand the city as a homogenous entity, with limited know-how on the variability of QoL at the neighbourhood level.

Review of Concepts, Tools and Indices for the Assessment of Urban Quality of Life

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Informal Settlements of Port Harcourt and Potentials for Planned City Expansion

This paper examines the changes in land use and economic activities between 1986 and 2005 in a residential development in Port Harcourt that was originally developed for senior civil servants and military personnel. It shows how land ownership has changed and also the rapid expansion of commercial activities within what was exclusively a residential development. With no enforcement of land use regulations, this has led to a decline in the quality of life for the residents.

https://eau.sagepub.com/content/22/1/259.full.pdf

The impact of land use conversion on a residential district in Port Harcourt, Nigeria

The Niger Delta Region in Nigeria considered the oil mineral producing area in the country has become a breeding ground for various forms of violence. The inability of residents in these areas to directly gain appreciably from the resources generated by the exploration and exploitation of this natural resource has contributed to this problem. Although it is now recognized that violence severely undermines broader development goals of growth and sustainability, a lot of policy research is dominated by quantitative methodologies. While obviously important, such highly quantitative methodologies fail to capture how people actually experience violence and also how it had impeded their livelihoods. This study, while placing a lot of emphasis on qualitative methodology looks at the interrelationship between ethnicity and violence and their effect on livelihood (on gender basis) in oil mineral producing areas in Nigeria. Resume La region du Delta du Niger, au Nigeria, consideree comme la zone de production du petrole, a l’echelle nationale, est devenue un cadre propice a differentes formes de violence. L’incapacite des residents de cette zone a profiter des

Gender, ethnicity and violence and their effects on livelihoods in the Niger Delta region, Nigeria: the case of Keegbara-Dere (Ogoni) and Bolo (Okrika) in Rivers state

This study has assessed urban residential quality of life in two neighbourhoods of Port Harcourt, Rivers State, Nigeria -drawn from the informal (waterfront) settlements that line the creeks of the city. The study set out to ascertain residents’ perception of neighbourhood attributes, residential quality of life as whole and the variables considered by residents to be the most important to enhance residential quality of life. Neighbourhood attributes were studied in situ without experimental manipulation and at one period in time, i.e. the study adopted a passiveobservational research design. The study utilized both secondary and primary data sources. Primary data was collected using face-to-face administration of a largely pre-coded household questionnaire, to a probability sample of 192 respondents, drawn from the 2 neighbourhoods. Data analysis was based on responses from 191 questionnaires retrieved and the univariate analytical method was adopted. The study found, that residential quality of life in the informal settlement of Port Harcourt Municipality was low with garbage in the neighbourhoods. There was no street lighting in the neighbourhoods, periodic flooding occurring in two the neighbourhoods. The study further revealed that 28.8% of the residents in these neighbourhoods were unhappy with their residential quality of life and 52.9% of the residents perceived their neighbourhoods to be of medium quality. A key conclusion of the study was that the improvement of neighbourhood residential conditions as perceived by the residents was important in raising residential quality of life, and recommendations included that in the provision of public infrastructure and services , the perceptions and preferences of the beneficiaries/target population must be taken into account to achieve user satisfaction.

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An Assessment of Residential Quality of Life in Informal Settlements in Port Harcourt Municipality

By surveying a 5% probability sample of residential clusters, yielding 369 residents in Port Harcourt, Nigeria, this study has ascertained actual recreational behaviour of the residents; determinants of recreational behaviour; perceived adequacy/inadequacy of government provision of recreational facilities; and residents’ suggestions for improvement of recreational facilities. It was found, amongst others, that weekly participation in passive (outdoor) recreation averaged 3.7 hours and 2.5 hours for females and males, respectively; the corresponding figures for passive (indoor) recreation were 35.2 hours and 43.9 hours. For active (outdoor) recreation males and females averaged 8.9 hours and 5.3 hours, respectively. The corresponding figures for active (indoor) recreation were 5.3 hours and 6.2 hours. Of 5 personality variables, income was the most potent in explaining recreational behaviour. About one half and 43.3% of residents considered government-provided indoor and outdoor recreational facilities inadequate, respectively, demonstrating the need for government to play more active roles in (i) providing

/pdf/patterns-and-determinants-of-recreational-behaviour-in-port-3fpba2wlc5.pdf

Opuenebo Binya Owei

Papers

Informal Settlements of Port Harcourt and Potentials for Planned City Expansion

The impact of land use conversion on a residential district in Port Harcourt, Nigeria

Gender, ethnicity and violence and their effects on livelihoods in the Niger Delta region, Nigeria: the case of Keegbara-Dere (Ogoni) and Bolo (Okrika) in Rivers state

An Assessment of Residential Quality of Life in Informal Settlements in Port Harcourt Municipality

Patterns and Determinants of Recreational Behaviour in Port Harcourt, Rivers State, Nigeria