A descriptive study design was adopted, combining a mixed-method approach. A descriptive study design refers to a type of research design that focuses on observing and describing the characteristics of a phenomenon without manipulating variables. It is primarily concerned with providing an accurate representation of the current state or situation. The method adopted in this descriptive study design include; case studies of regions/continents such as Asia, America, Europe, etc. within a specified time period (1990-2020) by monitoring the rate of deforestation and the observation of the deforestation rate in Ghana. This was further supported by the scientific literature.

When combined with a mixed-method approach, it means that the study incorporates both qualitative and quantitative methods to collect and analyse data. This combination allows researchers to gain a more comprehensive understanding of the research question using both numerical data and textual information. The relevant and related literature on mountain economies and ecologies was reviewed in a global context and in comparative situations in Ghana. Special attention was paid to the impacts of urban development on the livelihoods of mountain people and the environment. Internet searches of peer-reviewed papers in scientific journals were contacted. The researchers also collected existing evidence using grey literature (reports, working papers, and government documents). This grey literature broadens the scope of data collection beyond peer-reviewed journals and academic publications. The paper is an integrated, interpreted presentation of the data reviewed.

Scholarly databases such as scientific papers, book chapters, and reports have adequately described economic activities that take place in mountainous areas ( Klein et al., 2019). Due to the increase in human population, it makes land a limited natural resource for human economic activities, and this accounts for the human settlements in mountainous areas. Some of the economic activities in mountainous areas include the construction of hospitality centres like hotels, the construction of schools, hospitals, and various income-generating ventures ( Von Dach, 2017). The World Conservation Monitoring Centre (WCMC) plays an important role in providing useful information on population in mountains ( Kapos, 2000). The density of the gridded land population was the first global assessment of populations living in mountains ( Bhaduri et al., 2002). This was carried out in the year 2000 ( Huddleston et al., 2003). Current research on mountain populations includes analysing mountain populations in the Global Mountain Biodiversity Assessment (GMBA) ( Körner et al., 2011). This also categorises populations into groups and classes based on the extent and levels of human habitation ( FAO, 2015). Populations living in mountains in the world have experienced a sharp growth from 550 million in 1975 to more than 1050 million in 2015 ( Ehrlich et al., 2021). Human habitation and human activities are highly observable characteristics in mountainous areas: the areas of mountains that are occupied by economic activities of man increase and expand very rapidly ( Ehrlich et al., 2021).

Data from mountainous areas of the WCMC and the GMBA are critical in the classification of mountains based on their levels of population densities ( Ehrlich et al., 2021). The red dots in Figure 1 represents the GMBA ranges that comprise both urban and rural populations, while the green dots represent the ranges occupied by rural folks.

Forests provide habitat for most of the planet’s resources ranging from animals to indigenous important plant resources. More importantly, they keep continual flow of existence from production to consumption. However, deforestation threatens the gains from natural resources ( FAO, 2020). Figure 2 shows the net forest area change across the continents with its respective time interval from 1990-2020.

The differences between different continents regarding gains or losses in forested areas must be seen against the background of the differences between continents by 1990, as reported by UNEP’s GLASOD project ( Table 1), as summarised by Oldeman (1994).

The two continents that showed increases in their forested areas after 1990 (Asia and Europe) were seriously deforested by 1990 and drastic measures were required to improve their situations. The 1990 figure for Europe was very high, considering that the deforested area of this small continent was significantly higher than for Africa and not much lower than for South America. So, by 1990 both these continents started at relatively low points and could improve. The 1990 figures for Central and North America and Oceania were very low and remained very low. The figures for South America were high by 1990 and became very high for 1990 to 2010, but the large decline in the deforestation rate thereafter is promising. The trend for Africa is of great concern considering that the rate of deforestation was increasing throughout the period.

The achievement of many of the Sustainable Development Goals (SDGs) is hindered by the rate of deforestation in many economies, including South America. Population growth automatically influences the rate of deforestation ( Franco-Solís and Montanía, 2021). Farming activities in South America, specifically the surrounding areas of Brazil, are projected to increase over the coming years as more food is required to feed the growing population ( Swann et al., 2015). Numerous researches attest to the fact that the main driver of deforestation globally is the increase in the demand for food, as is evident by the increase in population growth and the satisfaction of many nutritional requirements ( Franco-Solís and Montanía, 2021). Since 2008, deforestation has been evident in urban development, agriculture activities (including cattle breeding) as well as the expansion of infrastructure amenities such as roads, dams, and highways in the Amazon basin ( Paiva et al., 2019).

In Africa, rosewood is one of the illegally traded plant species. Rosewood is one of the highly economic plant species that is in high demand by foreigners, especially the Chinese ( Lawson, 2015). Most African countries play an important role in meeting global demand, with African countries supplying more than 80% of the total annual rosewood to China ( Dumenu, 2019). The IUCN has listed African rosewood as an endangered species due to its high demand and overexploitation by foreign nationals ( Barstow, 2018).

In Ghana, increasing urban migration has made it difficult for people to acquire land to build in lowlands and, therefore, led to the construction of houses in mountainous areas, with its accompanying negative environmental and economic consequences. Cobbinah et al. (2015) and Songsore (2009) found that there is a rapid increase in population growth, coupled with decreasing land spaces for building. According to Amoako (2015), Cobbinah & Darkwah (2016) and Cobbinah & Korah (2015) this has led to the overexploitation of natural resources, including those in the mountainous areas. This obviously has negative impacts on socioeconomic development and the environment. In most densely populated cities in Ghana, urban dwellers have begun to build in mountains ( Siade, 2019). Mountain real estate developers are responsible for the deterioration of nature; for example, falling rocks ( Siade, 2019). This is gradually becoming the norm in Ho in the Volta Region of Ghana. The buildings found in the mountains of Ho are mainly used for tourism, hospitality, and residential activities. In other parts of the world, hospitality and tourism buildings or services are provided in mountainous areas, as many people prefer green and quiet places to relax during festivities ( Ciolac et al., 2017).

The differences in forest cover loss between different countries and regions may be caused by differences in the anthropogenic needs of people. Human activities and climate change are the main determinants of land use and land cover changes ( Ahmed et al., 2009). This is exacerbated by urban development and associated infrastructure amenities located in mountains, since it is believed that in most African countries mountains provide a peaceful atmosphere and climatically more comfortable conditions for people because they are cooler than the associated lowlands. Classic examples of this scenario in Ghana, and specifically Ho, are Volta Serene Hotel, Sky Plus Hotel, Hotel, and African Hills Hotel which are located at high elevations in mountains and are excellent examples of mountainous buildings emerging in Ghana in recent times. The latter type of development is not due to the scarcity of land space for human habitation, but it brings a ‘social status’ in society.

Studies evaluating changes in land cover in socioeconomic situations were conducted using Remote Sensing and Geographic Information System (GIS) approaches ( Karki et al., 2018). The increase in human population was found to be the main factor responsible for the overexploitation of natural resources (forests and land) in the Upper East Region of Ghana ( Kleeman et al., 2017). According to Jiang et al. (2015), the expansion of economic activities in urban centres is the main reason why Ghana’s natural resources are being depleted. This is because residential and industrial areas are developed into natural land to cater for the needs of expanded urban populations. Several studies reported a consistent decline in forest resources in rural and peri-urban areas of Ghana due to urban expansion ( Frimpong, 2015).

Although there are reasonable data on the impacts of land use and land cover changes on forest resources, there is a lack of literature on the gradual and consistent development of urban areas in mountainous regions in Ghana and their impact on forest dweller livelihood. This should be of great concern because mountains are in undisturbed conditions covered by forests. Urban development in the mountains leads to permanent destruction of forest resources. This has dire consequences for forest dwellers, since the forest resources provide ecosystem services such as food, medicinal, wood (for construction, fuel, furniture, etc.), water, recreation/tourism services, and many more ( Chamberlain et al., 2020) which translate into livelihood and economic benefits. It has become imperative to conduct research on the impacts of urban expansion in mountainous areas of Ghana on the livelihoods of forest dwellers and the environment. This will provide a basis for formulating policies that will protect Ghana’s mountains and associated natural resources.

Due to the limited land space for human economic activities, further exacerbated by the rapid increase in human population, humans have begun to develop mountainous regions into commercial and residential properties ( Ding and Peng, 2018). The means by which the natural resources of the environment are utilised define what urbanisation is. The expansion of cities and urban centres poses a significant impact on the natural resources of the environment, as the ecological footprint of humans increases. Therefore, this has led to numerous environmental problems that are dominant in the world today. The sustenance of the environment is the foundation for all sustainable and meaningful development. This is so because if natural systems are allowed to deteriorate, then there will be no human development that will cater for generations yet unborn ( Ding and Peng, 2018). The earth’s surface consists of about a quarter (1/4) of mountains and significant life forms are found in mountains ( Löffler et al., 2011). Mountains are also reservoirs for essential physiological requirements of man such as plants (food), water, and an economically vital commodity such as energy ( Payne et al., 2002).

Most of biodiversity including plants or herbs, animals, and many others can be found in mountains ( Payne et al., 2002). These plants and animals play essential ecosystem services that help to have a stable ecosystem for all. Urban development in mountainous areas has become a critical issue globally ( Blyth et al., 2002). UNFAO has been working in collaboration with the United Nations Development Programme (UNDP) on suitable ways to promote sustainable development of mountainous regions since 1998. This project was carried out specifically on urbanisation, livelihoods, infrastructure development, and education on sustainable urban development in mountainous areas ( Romeo et al., 2015) Critical environmental consequences in mountainous regions include the destruction of plant and animal life forms, air pollution, development of steep hillsides, ecological disasters, and the extinction of wildlife and plant resources ( World Bank, 2015). People living in mountainous regions seem to be making no progress in achieving economic stability and environmental sustainability, since urban development in mountainous regions poses a threat to the survival of biodiversity ( Romeo et al., 2015).

One of the consequences associated with urban development in mountainous areas is the destruction of the ecological state of the environment ( Leal Filho et al., 2017). Urban development in mountainous areas leads to a shift in the ecological conditions of the area ( Keenleyside et al., 2010). The shift in the environmental condition adversely affects most especially indigenous people living around these mountainous areas, leading to the neglect of farmlands owned by the community people ( Keenleyside et al., 2010). The neglect of farmlands in these mountainous regions takes a heavy toll on subsistence activities. Whenever there is a decline in the subsistence livelihood operations of community members living around these mountainous areas, it impacts their cultural, social, economical, and environmental lives ( Brunner et al., 2017).

Most parts of the world found in mountainous regions have different physical and biological environmental states, including climate conditions and biodiversity. One very essential information that is highly linked to mountainous urban development is the social implications for dwellers (indigenes who live in mountainous regions). Mountainous areas have a high level of social groups. This is because mountainous regions in many countries consist of a significant land mass, which implies that a sizeable number of people live around these areas and earn a living from farming operations ( World Bank, 2011). Indigenes living close to these mountain regions collaborate in community agricultural projects such as the construction of irrigation canals, potable water, and many more. Community households living in the mountains also participate in farming activities as labour, where labour is used as a ‘barter agricultural system’. This ‘barter agricultural system of labour’ is the system in which community members form groups and work on the farm of each other without demanding money ( Bhattarai, 2006). However, if farms in mountains are destroyed due to infrastructural expansion and urban development, then the social labour groups of indigenes around mountain areas will also disappear. Therefore, this has a social implication regarding the participation of community labour.

Governments face a major challenge when it comes to the implementation of policies on urban development planning. Attempts to ensure sustainable and equal development seem to favour only those in urban centres. This is evident when it comes to the availability of social amenities and quality human resources, which mostly identify with urban areas ( Opoku-Asare and Siaw, 2015). The mainstay of most rural communities in Ghana is farming with very little/no access to credit/financial support, as well as poor infrastructure amenities. For example, most of the roads that lead to farms in rural communities are in deplorable conditions ( Baffoe and Matsuda, 2018). These conditions in rural areas are responsible for many people, particularly young people, migrating to urban centres in search of better living conditions ( Awumbila et al., 2014).

Until now, most of the African population was found in rural areas. During the late 20 ^th century and the beginning of the 20th century, Africa was considered the fastest region in the world to transition to urban areas ( UNDESA/PD, 2012). In 1950, the urbanisation level in the African subregion was 14.4% and in 2000 it saw a stark growth to 35.7%, with a slight growth to 39.2% in 2010. It is projected that there will be an increase of 57.7% by 2050. It is important to note that in Africa, the rate of urbanisation in regions is not equal between different countries ( UNHABITAT, 2014).

Cobbinah et al. (2015) and Cohen (2006) postulated that urbanisation in Africa is not carried out in a manner that will protect the fortunes of future generations. The reason for this is based on the fact that urbanisation in Africa is primarily tied to social, political, and economic considerations, with minimal considerations of environmental sustainability ( UNHABITAT, 2012). Urban regions in Africa have low priorities in terms of environmental protection ( Tacoli, 2009).

Urban expansion in Ghana provides an idea of how urbanization situations occur in other African countries. Ghana has a total land space of about 238 537 km ². The entire increase in Ghana’s population is consistent with the expansion in the cities. This is to say that, as the overall population in Ghana experiences a growth curve, the population in the urban areas also experience a growth curve. Equal numbers of the entire population in Ghana settled in the cities and rural areas in 2010 ( Ghana Statistical Service, 2012).

In countries around the world, forests have been converted to agricultural lands. Some of these and some forested areas have subsequently been converted to urban areas for residential and commercial purposes due to the rapid increase in population growth ( Peerzado et al., 2018; Cobbinah and Erdiaw-Kwasie, 2016; Asamoah, 2010). As a result of this phenomenon, governments around the world have developed land use policies and strategies to mitigate the negative effects of urbanisation ( Jain et al., 2018; Aribigbola, 2013; Boamah et al., 2012; Thurman, 2010).

The Physical Planning Departments of the Municipal Assembly work with policies on land use which are very efficient in achieving sustainable development ( Bonye et al., 2020). Physical Planning departments play crucial roles in providing advisory services on efficient use of land, as well as helping implement the best available land use options in a sustainable way. This means that the resources in the environment are protected while people use lands for economic activities such as the construction of residential and commercial apartments ( Oluwasey, 2019). Although the Physical Planning Departments play central roles in the use of land in Ghana, their role is frustrated by the traditional political systems and the political elites. These political elites have little or no knowledge about urban planning and land use regulation. They have a lot of influence when it comes to the allocation of land for development projects without consulting urban planning professionals ( Amoateng et al., 2013). This makes the role of the planning departments of the municipal assemblies almost nonfunctional ( Djokoto and Opoku, 2010).

The implications of forest destruction for the livelihoods of forest dwellers are devastating and can be inferred from the absence of mainly nutritional needs and the economic cushion that forests provide. Rapid decline in forest lands has become a serious threat to food security and income generation, especially populations in forest fringe communities whose livelihoods are based on forest resources ( Baul et al., 2021). Agroforestry is one possibility to meet the three (3) pillars of sustainability, which are economic, environmental, and social benefits. This is because agroforestry provides rural populations with access to nutritious food (SDG-2) and improves their economic lives (SDG-8) ( Nair, 1990; Islam et al., 2013, 2015). Agroforestry systems have been formulated to provide economic respite to farmers, increase crop yield, improve soil fertility, conserve natural resources and ‘clean up’ a significant amount of carbon in the atmosphere ( Jose, 2009). An agroforestry system is the practice of growing crops that are interspersed with trees, and it contributes immensely to meeting the three (3) tenets of sustainability which include Economic, Environmental, and Social benefits ( Tamirat & Mekides, 2020).

Although forests are critical in providing ecosystem services, such as meeting nutritional needs and contributing meaningfully to the economic lives of people, especially forest dwellers; an increase in human population poses a threat to forests. Payn et al. (2015) agree with findings that the increase in human population is responsible for the overall depletion of natural resources and thus undermines sustainability. This is in agreement with Fanuel et al. (2023), who also opined that the growth in human population stands in the economic benefits forests provide to forest dwellers since humans cause overexploitation of forest resources. To achieve sustainable exploitation of forest resources, institutional frameworks must be well-resourced and equipped with human capacities and the agrotechnology or tools needed to work with in achieving the desired results. This is in agreement with Hasnaoui and Krott (2019), who also stated that in order to utilise forest resources sustainably, the institutions responsible for ensuring this play an important role. With this in mind, one may ask: Are state institutions responsible for ensuring sustainable forestry management adequately equipped with the needed human resources? Do these state institutions and NGOs have adequate facilities in terms of agricultural technologies? If not, what steps are being taken to have access to these agricultural technologies in agroforestry systems? These questions will help address the challenges of rapid depletion of forests and, if properly addressed, will enable forest dwellers to derive maximum economic and nutritional benefits from forests.

Soil degradation is intensified by anthropogenic activities such as deforestation, construction works and many more. These human activities pose heavy threats to the stability of the soil and make it vulnerable to wind and water erosion. This therefore has adverse impacts on the nutrient retention of the soil which translates into low crop yield and subsequently low income ( Figure 3).

Generally, the sharp increase in human population against the fast-diminishing natural resources is a manifestation of the important role of the Physical Planning Department in issuing building permits ( Bonye et al., 2020). As a result of the increase in population growth, pressure is mounted on the limited natural resources like land for residential, commercial, and social activities ( Li et al., 2019; Peerzado et al., 2018). Everywhere around the world, especially in urban centres, land is a very important commodity for economic value and development ( Mutiara, 2008; Saiz, 2010; Pavri et al., 2012). In most urban areas around the world, including Ghana, economic opportunities such as the construction of educational facilities such as higher education institutions, and the construction of recreational facilities for leisure require land ( Bonye et al., 2020) and this makes the role of the physical planning department extremely important in ensuring sustainable development.

However, the smooth operation of the planning department of the municipal assemblies is thwarted by the efforts of political elites who are nonprofessionals, influencing decisions obviously for their parochial interests ( Djokoto and Opoku, 2010). This is in agreement with the findings of Adjei-Poku (2017), who stated that even though land use planning plays a central role in sustainable development in developing countries, the efforts of urban planners are sometimes negated by the political class.