Evaluation of Sustainable Maintenance and Security of Green Spaces in Public Housing Schemes in Lagos State, Nigeria

Security of lives and property in housing environments is one of the basic necessity in the provision of public housing. The nature of maintenance given to green spaces in public housing environment can affect the level of security of lives and property. However, due to the antecedents of public housing, its unique population and the problems it creates for law enforcement agencies on security issues, there is need to evaluate how sustainable maintenance of green spaces within public housing could affect the level of security of lives and property. The public housing constructed by the Lagos State Development and Property Corporation (LSDPC) in Lagos State, Nigeria was used for this study. Primary data was collected from 1036 housing units in 12 different estates of the LSDPC in Lagos State, using the research tools of the questionnaire and structured observation schedule. Descriptive statistics and categorical regression analyses were carried out on the data. The results showed that the green spaces around each housing units were sustainably maintained, than jointly owned green spaces by all residents of the housing estates and this has implications to the level of security of lives and property in the housing estates. It is recommended that public housing estate’s green spaces be designed to allow for sustainability in maintenance by each housing units, which would lead to a general sustainable maintenance view of all green spaces available in the public housing environment.


Introduction
Public housing is a form of housing type provided by governments to meet housing needs in most urban settlements.This is due to an increasing population growth of urban areas.More people are moving into cities and towns from the rural areas, causing rising needs in housing deficits.The needs for accommodation in cities had brought about environmental degradation in terms of low green vegetation in urban areas.Study such as [11] measured urban greens index for better planning of cities. Majority of spaces available in the urban areas are built up, creating more rooms for residential buildings.However, the need for green vegetation cannot be over emphasised.Deforestation, which is defined as the intentional and permanent transition in vegetative cover of a place and intended permanence of a change in land use from the growing of trees, greens to some other purpose, such as built up spaces [5].This situation does not just start in a day, but a gradual process, when green spaces are or cutting of trees within neighbourhoods or green spaces are neglected and not maintained.In the design of public housing, incorporation of green areas and spaces is encouraged as stated by the study of [34]; [7].The health benefits of green spaces within the high population that characterise public housing is very advantageous, it enhances and makes prevention of crime strategies more effective.Furthermore, apart from the health benefits of green spaces, the maintenance of green spaces within residential environments has been identified by scholar has a means of crime prevention within such environment, this has been argued for with different theories of crime preventions, such as defensible space theory, crime prevention through environmental design and broken window theory.The design of public housing should incorporate green spaces, both for IOP Publishing doi:10.1088/1755-1315/1342/1/012026 2 aesthetics, health benefits and for safe environment.The design of public housing, both the interior and the exterior spaces could have effect on the level of crime within residential neighbourhood, highlighted by [18]; [12].This study evaluated how sustainable maintenance of green spaces within public housing could affect the level of security of lives and property by evaluating the frequency of maintenance and use of the open spaces, the level of security and the resident's satisfaction with the level security within the studied housing estates.Lagos State Development and Property Corporation (LSDPC) public housing schemes in Lagos State, Nigeria was used as case study, this scheme was one of the earliest attempt of Lagos state government in the provision of public housing scheme in Lagos, establish in 1973.The housing schemes of LSDPC were essentially prototype multifamily apartments spread across various locations within Lagos State.Data used for the study was extracted from a field study that was conducted in 2016/2017.This study contributed to knowledge by presenting from the results, the importance of adequate maintenance of joint green spaces in public housing estates, as it has implications to security within the housing environment, especially in developing country such as Nigeria.

Importance of Green spaces in Residential Environments.
The importance of having green spaces in any environment is stressed and considered as part of housing adequacy by different studies.[6] studied the preference of residents to the public and private green spaces and found that both had its unique importance, there is a unique combinations of functions and meanings attached to green spaces in the two instances, a suggestion that green spaces in any residential environment, either private or public is deemed to be part of dwelling consideration.Green spaces contributes to the liveability of dwelling and brings the residents closer to nature, with the healthy implications of having green spaces in the residential environment as described by [35] ; [19] ; [36].The health benefits are both physical and psychological, having effects on cardio-and cerebro-vascular disease, diabetes, colorectal cancer, osteoporosis, depression and fall-related injuries, mental functioning improvements, mental health and well-being and life longevity ([19]).The study found that green spaces in residential environments gives opportunities of space for physical exercises such as walking and having in mind that for a completely built up area, there is constrain on physical activities.Other studies have shown that green spaces in housing environment can be associated with increased survival in older populations and lower stroke mortality ( [33]; [19]).In other studies by [4]; [22]; [32] have identified an indirect benefits of urban green spaces in the reduction of crime in cities in the developed world.A sustainable environment needs to be protected as described by [3] and green environment propels sustainable environment.Furthermore, green spaces in residential environments have been found to contribute to social capital, it provides a meeting place for the residents to maintain neighbourhood social ties, whereby this is very significant to the neighbourhood having sense of safety and security within the residential environment ([29]).[35] Study's findings also supported the idea that green space can provide a buffer against the negative health impact of stressful life events.Apart from the healthy importance of green spaces, the benefit of environmental aesthetic is of advantage.The study of the [23] on the city of Kumasi, Ghana on destruction of urban green spaces, showed that apart from the destruction of urban green spaces through urbanization, other factors can lead to a total unappealing aesthetic view of green spaces and the environment, which are lack of enforcement of development controls by government, low priority given to green spaces, the problem of ownership of green space; which can lead to poor culture of maintenance, uncooperative attitudes of the general public and lack of coordination among the allied professionals on green spaces to play a critical role in the destruction of urban green spaces ([23]).Green spaces in cities and towns have implications for the physical, social, economic and ecological effectiveness of the citizen to function well and for a good satisfactory and quality of life ([14]).Also, [31] had argued that failure to plan for green spaces and to have trees in new low-cost housing environments is a denier of having opportunity to improve the overall urban sustainability and liveability, constraining the potential flows of tangible and intangible benefits to urban residents.

Environmental Security with Green Spaces in Public Housing.
Public housing has been described as a form of social housing that depended on public fund for its delivery.The housing types are either managed by the governmental developers or sold out rightly to the public.A subsidized housing projects by the government in an effort to meet housing deficits to its citizenry and in most cases the low-income earners, as described by [13].Public housing has been identified with numerous shortcomings, such as over population, degradation, low maintenance culture, violence and crime.Crime and lack of security is a problem that when allowed to persist in residential environment hinders most other activities and living standards of residents.Different measures has been used to deter crime in public housing, many that has to do with planning, building designs, policing and technology devices.Most of the related crime prevention strategies identify the environment as one of the useful tool in the prevention of crime in residential environment.Green spaces in public housing is an effective measure to be adopted amongst others.
In a study carried out by [32] in three largest metropolitan areas in Indonesia to know the effect of green space on the probability of crime occurrence, the study observed that with the reduction of green spaces in the studied area, there is an increase in crime.Findings from the study also argued against the common perception of relating urban green spaces with violence and crime.The study concluded that the presence of nature in form of green spaces, reduces crime in urban areas.This suggested that, in as much as public houses are situated mostly in urban areas, where population increase is being met with these housing types, close attention is required to security of green spaces in public housing environments and this could be achieved by a well maintained green spaces.

Maintenance of green spaces in public housing and crime prevention strategies
The desire to meet security needs in public housing and its management are being propelled by different crime prevention strategies such as defensible space theories of Oscar Newman in 1972, a model for residential environment, which can prevent crime by creating a physical and social fabrics that defend itself.Creating a territoriality that ensures a safe, productive and wellmaintained living space, where a potential criminal perceives such a space as controlled by its residents.This has been demonstrated in different studies globally such as [8].In a study carried out in Tawan Melati resident area of Kuala Lumpur city, Malaysia by Malathi and Mathi (2010) to test the effect of physical design on the occurrences of crime, found that merely providing housing (public housing) does not guarantee success of the housing development and policies or residential satisfaction.This suggests that mass housing entails, among other things, meeting the security challenges of residents at the design and post occupancy stages.
Different countries have embarked on various programmes in a bid to prevent or control crime and disorder in residential neighbourhoods.For example, Malaysia adopted "safe city programme" which is focused on creating violence and crime free cities ([21]).In their study, [21] argued that changes in the built environment and modification in space design can impact residents and offenders' perceptions of criminality.It can also be argued that the peculiar images portrayed by public housing, coupled with other design features and the social characteristics of the residents' population make such houses a peculiarly vulnerable target to criminal activities.Most spaces in public houses are jointly owned with little or no demarcation to show private ownership.With this, the spaces are used by all the residents, and as such cannot be defended and cared for.However, when the spaces are divided into smaller units or groups, the essence of defensible space and Crime Prevention Though Environmental Design (CPTED) can be fostered.

Interior and Exterior Space Usage and Security of Residential Neighbourhoods.
The concepts of space, place and their characteristics in architecture as explained by [27] showed that space and place are among the fundamental concepts in architecture around which many other discussions have been held in terms of their complexity and importance.The use of space especially residential spaces, both the interior and exterior, is determined by the social nature of such space ([9]).It is argued that there are connections between space and the society, and thus focus should be on this relationship ([9]).Social life can shape the use of space and thus the nature of the social life of any dwelling can be exhibited and seen in their use of both indoor and outdoor spaces.
[26] had earlier explained that the use and control of space outside apartments by the residents are considered as intervening variables in deciding the effectiveness of the design of the interior space.These are the best pointer to the extent of residents' sphere of influence over areas adjacent to their apartments.The bigger the building, the less frequently residents will use the space outside their apartments and in turn, the lower the control over the space.Low use and control will, in turn, lead to a high occurrence of crime, as well as high level of fear ([26]).The physical design features of dwelling environments urges the people to extend their area of influence beyond the immediate confines of their homes, which can inhibit criminal activities.Notably, one question that is emanating from studies that have examined the effect of the size of building on exterior space usage is: "does the size of exterior space affect the use of exterior spaces of residential dwelling?Even when the use of exterior spaces is more, does the outdoor areas afford safe, comfortable, inviting opportunities for walking and other activities.
The design of exterior spaces should give opportunities for residents' contact, seeing and hearing experiences.This was highlighted by [10] in the study of life between buildings, where he explained that different exterior activities within residential areas can be divided into necessary activities, optional activities and social activities as further discussed.
(i) Necessary activities: -These require the participation of those involved and include going to school or work, shopping, waiting, running errands, everyday tasks and pastimes.These activities take place throughout the year, under nearly all conditions and they are more or less independent of the exterior environment.The participants have no choice but to be involved in them.(ii) Optional activities: -These are activities that the participants wish to take part in.They include, taking a walk, standing or sitting around enjoying life.Such activities take place only when exterior conditions are favourable.They have a lot to do with the physical planning of outdoor in terms of quality and friendly design.When the place and the situation are inviting, there is an occurrence of a wide range of optional activities.(iii) Social activities: -are activities that are depended on the presence of others in the public space.The social activities are dependent on the success of the other activities.
The design of exterior spaces should give opportunities for people's contacts, opportunities for meeting and daily activities.In a situation where the quality of the outdoor areas are favourable, optional activities tends' to occur with increasing frequency.In addition, as the levels of optional activities increase, the number of social activities of the people is expected to rise substantially.
The quality of the interior space of a house as noted earlier should satisfy some criteria for activities to be viable.These include continuity, privacy, self-expression and personal identity, social relationship, warmth and a suitable physical structure ([17]).This suggests that culture is very relevant in the use of interior space.A survey of twenty-three different subjects (respondents), including 11 couples to elicit statements describing the attributes of home and non-home environments was conducted by ([16]; [17] ).The study found that security, sense of belonging and dissatisfaction with their domestic role appeared to be more salient expectations of a home, more especially among female respondents.However, the study by [28] on the effects of satisfaction with dwelling units, estate interior and exterior environment on psychological well-being of the residents shows that the interior environment had a greater impact on residential satisfaction than the exterior environment.Although that study was carried out on aged people of over 60 years, yet the finding can have general implications since residential environment in which the residents had resided in was for over a period of time.
The study also shows that there was a correlation between advancement in age and the use of interior space.
From the foregoing, it can be inferred that space provision (both the interior and exterior of residential building) should be that which is of good quality.The type that makes it impossible for the building users to act on their own in providing some basic features and facilities they require.This means that remoulding of interior and exterior spaces to achieve comfort, security, identity and a good community spirit within their neighbourhood, must be avoided as much as possible as these may have security implication on the long run.

Methodology
This study used survey method, a case study of the public housing estates provided by the Lagos State government, through the Lagos State Development and Property Corporation (LSDPC) in Lagos State Nigeria.Lagos State is regarded as the commercial nerve centre of Nigeria, with population density of 2,593.7/km 2 (6,717.8/sqm)and total land mass of 3,475.1/km 2 (1,341.7/sqm).The State is located in the South-western Nigeria.The Lagos State Bureau of Statistics (2015) indicated the population of Lagos State to be 17, 552 as at 2013.
The history of public housing in Lagos State spanned from the late 1920s to 1972 with the establishment of LSDPC tasked with the responsibility of providing prototype multifamily apartments, Low-income, high rental medium income and upper medium accommodation spread across the local governments areas of Lagos State.The geography of the state comprises of Lagos Island and Lagos Mainland areas, with the lagoon between.There are 16 local government areas of the state, Figure 1 shows the map of Lagos State with the 16 local government areas.This study used the LSDPC estates constructed between 1972 and 1992 as shown in Table 1.There are 14 LSDPC estates constructed between this time distributed around the local government areas of the state, which are, Abesan, Amuwo-Odofin, Dairy Farm /Ijaiye, Dolphin/Ikoyi, Opebi/Maryland, Iponri, Isolo, Ojokoro, Ijaiye/ Ogba Phase II, Ebute -Meta, Alapere, Omole, Iba and Femi Okunu LSDPC housing estates.From which 12 estates were selected for this study shown in Table 1.
6 Iba and Femi Okunu estates were not taken as part of the sampled estates, Iba housing estate is within the same area of Lagos State as Amuwo-Odofin and Femi-Okunu, also is on the Island just as the Dolphin/Ikoyi estate.The number of housing units in both Amuwo -odofin and Iba estates are very large, which may not allow a proper coverage of the other estates if both are used in the survey.Ijaiye low-cost and Ogba Phase II estates were merged and additional number of units were surveyed in the medium housing.This is because both estates are in the same location and are together.The strategy used in determining the exact number of housing units sampled in each estate was calculated using the proportion of the number of housing units for each estate in relation to the total population shown in Table 1.The aggregate number and percentage of housing units sampled are also presented in Table 1.Primary data was obtained from head of households or a representative of the household in each housing unit selected in the housing estates through the use of structured questionnaire as research tool.Systematic random sampling method was adopted in the selection of the housing units used, this is because of the similar type of housing units within each estate.Thus, there are variations in the number of housing units in each building in different estates, some with 8 housing units, 6 housing units and 4 housing units within a building.In this process, every 11 th house was selected.Stratified sampling method was adopted initially to group each estate into strata and then use systematic sampling for the selection of the units; this was due to the large number of housing units in each estate.One questionnaire per each sampled household.Observation schedules was used for every estates sampled.Sections from the questionnaire was used to obtain data of the respondents socio-economic characteristics, maintenance of green spaces (private and public), the estates environment and the use of the exterior spaces of housing units.5-point Likert type scale structured questions with 1 representing Never; 2 for Rarely, 3 for Not Sure; 4 for S= Sometimes and 5 for A=Always and for other sections of the questionnaire 1 representing Strongly Disagree, 2 for Disagree, 3 for Not Sure , 4 for Agree and 5 for Strongly Agree.The analysis was carried out with the use of the Statistical Package for the Social Sciences (SPSS) software, using analysis type of descriptive statistics of frequencies and percentages to describe the socio-economic and demographic characteristics of the respondents, maintenance of the estate environment and green spaces and the use of exterior spaces.Also, Categorical regression analysis was carried out to evaluate the influence of the frequency of maintenance of green spaces and the level of security in the housing estates surveyed.

Results and Discussion
Table 2 presents the socio-economic and demographic characteristics of the respondents in the surveyed LSDPC estates.3 showed that open spaces within the estates are not just used for green spaces, but other activities such as businesses, social and religious activities.4 with large frequency numbers to sometimes and always participation in these activities, suggested that a large number of respondents participates in the maintenance of green spaces in the estates.Although, this green spaces are seen to be more of the spaces within the control of each housing units (a privately owned green spaces) than jointly open spaces in the estates with are being used for other purposes.The result of Categorical Regression analysis carried out is presented in Table 6, Table 7 and  Table 8, with the general security in the estates as the dependent variable and the frequency of  6 and Table 7 respectively.Source: Authors' compilation (2021).
The regression result with F 37, 998 = 5.796, P= 0.000 reveals that 5 factors accounted for 44.4% of maintenance of Green Spaces and the Level of Security in the housing estates.Table 8 shows the factors and their levels of contribution.From Table 8, the β values evidently showed that security of streets and walkways has the highest β value of (0.385, F = 20.435,P = 0.000).Followed by adequate open space with β value of (0.195, F = 4.598, P = 0.011), next is pruning of flowers and trees with β value of (0.143, F = 4.369, P = 0.005),followed by marital status with β value of (o.135, F = 3.208, P = 0.041), next is open space for religious having β value of (0.107, F = 2.324, P = 0.074) and the least is general cleanliness with β value of (0.104, F = 3.052, P = 0.028).From the regression analysis showed that the security of streets and walk ways are most significant to maintenance of the green spaces, the estates having enough and adequate open spaces for greens.When the streets are safe, the maintenance of jointly open spaces can be carried out, with the pruning of flowers and trees which is also seen to be very significant.Also, from the result, marital status and general cleanliness of the entire estates are very significant in the maintenance of green spaces to have implication to the level of security in the estates.Although, there is general cleanliness in the estates, which is the least significant, a suggestion that there is more attention to the maintenance of green spaces close to housing units rather than general green spaces, as also shown in figure 2.

Conclusion and Recommendation
The need for security of life and property within public housing environment is very important, and can be achieved with providing adequate and well maintained environments such as green spaces within the residential environment.The study evaluated how sustainable maintenance of green spaces within public housing could affect the level of security of lives and property, by evaluating the frequency of maintenance and use of the open spaces, the level of security and the resident's satisfaction with the level security within the studied housing estates.The study used as case study the Lagos State Development and Property Corporation (LSDPC) in Lagos State, Nigeria.The study aligned with strategies of crime prevention such as the defensible space theory of Oscar Newman ([24]; [25]).Preventing crime in residential environment requires creating a physical and social fabrics that defend itself.Creating a territoriality, such as green spaces that ensures a safe, productive and well-maintained living space to deter crime in the residential environment.The study results showed that there is adequate open spaces for greens and there is sustainable maintenance of green spaces around each housing units in the estates surveyed, rather than jointly estates owned open spaces and this is done by pruning of flowers and trees.Also, from the result, the socio economic profile of the respondents in their marital status is significant and have implication to maintenance of green spaces and level of security.It is recommended that for urban areas and cities, with its increasing annual population growth rate and public housing schemes, which is being used as stop gaps to meeting housing deficits, there is need for a sustainable and preserved green spaces developments plan requirement by urban policy makers, governments, built environment professionals, especially in developing countries such as Nigeria.The study is limited in the coverage of the data collected, more data and continuous data collection in other public housing schemes may also be required for further study to substantiate the results of the study.Further study can also be carried out in public /private housing schemes types in the state, this would give the required information needed for adequate sustainable development needed in the residential housing security needed in the state.

Figure 2 ,
Figure 2, Figure 3, Figure 3, Figure 4 and Figure 5 showed photograph results taken from observation of maintenance and use of some of the open spaces in the estates surveyed.With the jointly owned estates green spaces poorly maintained than the green spaces close to housing units where the walk way are neatly demarcated.

Figure 2 :
Figure 2: Poorly maintained joint open space with grasses not cut and used as car park at Ojokoro Estate.Source: Authors' field work (2016/2017).

Figure 3 :
Figure 3: Clean and well maintained walkway and green space closed to a housing unit at Ebute-Meta Estate.Source: Authors' field work (2016/2017).

Figure 4 :
Figure 4: Kerbs demarcating the walkways from the flower lawn on open space around the building at Ebute-Meta Estate.Source: Authors' field work (2016/2017).
of open spaces in the estates environment, frequency of maintenance of green open spaces in the estates, frequency of level of security in open spaces and resident satisfaction and the respondents and residents socio-demographic variables as the independent variables.The model for the regression and ANOVA results are presented in Table

Table I :
The percentages of housing units sampled relative to the total population in each of the housing estates.

Table 2 :
Socio-economic and Demographic Characteristics of the Respondents.Presented inTable 3 is the frequency of maintenance and use of open spaces in the estates environments.The result showed that 475(45.9%)respondent agreed to adequate availability of open spaces in the estates, although 222(21.4%)are not sure of the presence of open spaces, a suggestion that this spaces may not be clearly defined and visibly seen.The purpose of this spaces may not be clearly defined for such use as the green space.This can also be predicted by the responses to open spaces used for residential purpose only, where a large number of 567(54.8%)agreed to this, a suggestion that more priority is given to build up spaces.This is seen also with the responses of open space being used for business purpose only, with 427(41.2%)responses, open spaces being used for religious activities 309(29.8%),social gathering taking place in open spaces with large number of 718(69.3%),open space used as additional space for shops 301 (29.1%).Although open spaces for gardening has 338(32.7%)responses agreeing to this and recreational and activities with 448(43.2),which are green spaces.The results presented in Table

Table 3 :
Frequency of Maintenance and Use of Open Spaces in the Estates Environment.

Table 4
presents the frequency of maintenance of green open spaces with grasses, landscape, flowers and trees.The results showed respondents agreeing to cutting and weeding of overgrown grasses in open green spaces in the estate to be 608 (58.7%), agreeing to replacement of damaged landscape in the estate 379(36.6%)and Pruning of flowers and trees in the open space in the estate 446(43.1%).From the results presented in Table

Table 4 :
Frequency of Maintenance of Green Open Spaces in the Estates.

of flowers and trees in the open space in the estate.
, Table5shows the respondent's satisfaction with the level of security in open spaces and the open spaces contribution to the level of security in the estates.The results showed that many respondents are satisfied with security of buildings' surrounding spaces, with 509(49.1%)agreeing to this and the satisfied with security of streets and walkways has 440 (42.5%).Contribution of activities of open spaces to security is 354(34.1%),Landscape contributing to security has 245(23.6%).However, many respondent seems to be satisfied with general security within the estates with 516(49.8%)responses, as against those that are not satisfied and unsure respondents having 171(16.5%),224(21.6%)respectively. Furthermore

Table 5 :
Frequency of level of Security with Open Spaces and Resident Satisfaction.

Table 6 :
The regression Model.

Table 7 :
The ANOVA Table.

Table 8 :
Coefficients of the Regression Analysis to identify maintenance and use of green space and open spaces that predict the level of general security in the housing estates.