A Review of the Economic, Social and Environmental Impacts of Tourism Development

The Tourism industry has significantly contributed to diverse social and economic benefits in host communities or regions. Despite the gains that have been realized in the sector, a surging number of negative impacts has been associated with tourism development. This current study reviewed the literature on the economic, social and environmental impacts of tourism. Tourism has helped boost economic growth, increased the revenue base, created mass employment, and enhanced the development of small and medium size enterprises in host regions. Despite its positive economic strides, it has contributed to negative outcomes such as the increase in commodities prices, high cost of living and unstable tenure of service in host communities. Tourism development has resulted in positive socio-cultural impacts such as infrastructural development, and cultural exchanges. Nevertheless, it has led to socio-cultural problems, including congestion, soaring crime rates, resentment and conflicts in host communities. On the environment front, tourism has created profoundly disappointing environmental problems. These include carbon emissions, ecological disturbances and waste management problems. The aforementioned environmental problems depend on the type and scale of tourism and the level of environmental awareness of inbound tourists. To maximize the gains of tourism development, its development initiatives must explicitly consider the social and environmental dimensions. Also, the involvement of host communities in tourism planning is pivotal to sustainable tourism development.


Introduction
The tourism industry has seen a worldwide boom over the years [1]. An estimated 1326 million tourist arrivals were recorded in 2017 indicating a 7% growth rate [2]. Tourists visit destination regions for various reasons ranging from cultural heritages, architectural designs and relief features to ecological endowments [3]. Tugcu [4] described tourism as a means of transferring financial resources from rich countries to developing nations. In 2019, the World Travel and Tourism Council reported that travel and tourism contributed an estimated 10.4% of global GDP [5]. Tourism is one of the drivers of economic growth in many regions of the world, considering its significant contributions to the Gross Domestic Product (GDP) of several nations. For example, it was estimated that tourism contributed to the total GDP in Greece and Malta was between 17% and 28% respectively [6]. Tourism is the main sector significantly contributing to economic growth in Malaysia [7]. The travel and tourism industry directly contributed 6.7% to Egypt's total GDP in 2011, and was projected to increase by 4.8% pa in 2022 [8]. Early work by Brida and Risso [9] projected that 100% increase in tourism demand can result in nearly 0.29% increase in elasticity of real GDP (29% growth) in South Tyrol in Italy. Furthermore, foreign currency receipts realized from the tourism industry normally exceeded receipts from the other sectors in many countries [9].
Tourism growth has resulted in a disturbing array of social, environmental and economic impacts especially in destination regions. These impacts include the change of local cultures, rise in prostitution and crime rate and the pollution of ecological sensitive sites and over use of water resources [10]. For example, tourism contributed to 4.4 million tonnes (Mt) in direct carbon emissions and 5.8 Mt in total domestic emissions in New Zealand [11]. The negative impacts of tourism development reflect the fact that tourism economic benefits cannot be fully maximized unless its social and environment dimensions are given thoughtful consideration [8]. Similarly, Urtasun and Gutiérrez [3] argued that the economic, socio-cultural, and environmental dimensions of tourism has tipping points. A high influx of tourists in a region may overstretched the existing infrastructures that could consequently produce negative impacts [3].
Because of tourism's negative economic, environmental and social impacts in destination regions, the concept of sustainable tourism has been gaining attraction in recent years. Sustainable tourism development (STD) is centered on a 'triple bottom-line' approach that takes into account three dimensions: economic, environmental and social in tourism development [12]. This concept has been the central theme of the literature on tourism in recent years, as researchers have been exploring the linkage between these three dimensions. For example, Tugcu [4] studied the relationship between tourism and economic growth in European, Asian and Africa countries based on data from 1998 -2011. Other researchers had studied the economic, social and environmental impacts of cruise tourism on local communities in Trujillo, Honduras [13]. Gao et al [14] investigated the relationship between CO 2 emissions, energy consumption, economic growth and tourism development in 18 Mediterranean countries using data from 1995 to 2010.
There is a paucity of reviews on the economic, social and environmental impacts of tourism. Huang et al. [15] had well reviewed the environmental impacts of the tourism industry. To the best of our knowledge, a comprehensive review on the three dimensions of tourism has not been identified in the literature, a gap, this current review seeks to fill in. Thus, the objective of the current piece is to document the economic, social and environmental impacts of the global tourism industry. The current study will help tourism planners to consider these three dimensions in tourism planning and development. It will help nations to maximize the tourism profits while minimizing its negative implications.

Economic Impacts of Tourism
The contribution of tourism to a nation's economy is often assessed by its effect on income, employment and total foreign exchange earnings [16]. However, tourism economic impacts can go beyond these relative shares [9]. The economic impacts of tourism have been described as 'direct effects' and 'derived effects', and these have been detailed in the work of other researchers [16]. Mochechela [17] argued that the tourism's economic impact on destination regions hinge on the location, type of attraction, form of tourism and the variety of local products or services available to tourists. In contrast, Urtasun and Gutiérrez [3] argued that tourism could create positive impacts on localities characterized by low non-tourism economic activities in contrast to those with high non-tourism economic activities. This section described the positive and negative economic impacts of tourism development.

Tourism Contribute to the Establishment and Growth of Small and Medium Enterprises
In recent years, tourism-related Small-Micro-Medium-Enterprises (SMME) have been recognized as drivers of poverty reduction [18]. There is massive literature that has proven that tourism promote the growth of SMME. For example, in Azerbaijan, tourism businesses increased from 96 in 2006 to 272 in 2016 and 339 in 2017 [19]. On the Balearic Islands in Eastern Spain, 86% of the study participants stated that tourism generated business opportunities for local residents [20]. In South Africa, the presence of the Pilanesberg National Park increased tourism related entrepreneur development as mentioned by 57.7% of residents [17]. In Hawassa City, Ethiopia Small Scale Tourism Enterprises significantly increased the income of 71 (57.3%) local residents [21]. In Peterborough, USA, tourism has contributed to a boom in real estate business as tourists buy expensive homes than their local counterparts through real estate agencies [22].

Job Creation
Tourism is one of the fastest-growing industries in terms of both income generation and job creation. Tourism is the largest industry that could employ both skilled and unskilled people [17]. In 2019, the travel and tourism industry created 319 million jobs which is 10% of the total employment worldwide [5,23]. It was projected that tourism will create 328 million jobs or 1 in every 10 jobs globally by 2022 [8]. However, the projection by Ayad and Ye [8] could be affected by the current COVID19 pandemic which has severely affected the global tourism industry.
Nevertheless, tourism has significantly contributed to employment in many nations. An early study in New Zealand showed that 'every 12 inbound tourists create one job for one year' [24].
In the USA, tourism provides direct employment for 8.8 million people and approximately 7 million more in 'indirect' and 'induced' employment [28]. On the Balearic Islands in Eastern Spain, 91% of the respondents agreed that tourism generated employment [20]. In Azerbaijan, employment in tourism enterprises excluding hotels and related businesses increased by 35.7% from 2009 to 2017 [19]. As of 2007, an estimated 30,000 people were employed in the tourism sector in South Tyrol in Italy [9]. An earlier report showed that tourism provided about 19.63 million jobs, including 7.8 million and 8 million direct and indirect jobs respectively in Mediterranean countries [6]. Also, in Denmark Tourism provides approximately 70, 000 jobs opportunities [16]. In Hawassa City in Ethiopia, small-scale tourism enterprises provided 1218 jobs for local people [21].
Despite the job opportunities provided by the tourism industry, the nature of employment has been another research domain. Tsundoda and Mendlinger [22] reported that tourism indeed create jobs for residents in Peterborough, USA, but the job duration was short and the salary was insufficient for many employees especially those bearing family responsibilities. In Sierra Leone 51% of respondents in the study by Thullah and Liu [26] stated that jobs provided by tourism are seasonal in nature. In tourism designated regions, the employment rate between locals and nonlocals by tourism industry has showed contrasting results in the literature. A study in Peterborough New Hampshire, USA, has found that tourism created few job opportunities for locals. This is largely due to the size of and the limited tourism businesses which consequently could employ a handful of people [22]. In South Africa, 45% of respondents mentioned that locals were employed in low cadre positions, 26% to professional positions and 21% as unskilled employees at the Pilanesberg National Park [17]. A recent study has shown that 94% of respondents agreed that tourism provided more jobs for locals in Sierra Leone [26].

Economic Growth
The role of tourism in economic growth cannot be overemphasized. International tourism receipts rose by 4.9% accounting for up to US$1340 billion in 2017 [2]. In 2018 alone, the contribution of the tourism industry account for 10.4% to global economic growth, doubling its 2011 level [5]. The total contribution of Travel and Tourism sector to world GDP is projected to increase by 4.3% pa in 2022 [8]. Tourism is being recognized as the main source of export revenues in 20 of the world's 48 Least Developed Countries (LDCs) [27].
The contribution of tourism to economic growth of a nation or region is called the tourism-led growth hypothesis [4]. Early report showed that the tourism sector in the Mediterranean countries contributed to 1019 billion US dollars in 2014, accounting for 11.3% of total GDP [6]. Tang and Tan [28] studied the impact of tourism on economic growth of Malaysia between 1975 and 2011. According to their analysis, both Johansene Juselius cointegration test and the Granger causality test showed that tourism had positively impacted shortrun and the long-run economic growth in Malaysia [28]. Chen and ChiouWei [29] used an EGARCH-M model to analyse tourism contribution to economic growth in Taiwan. They found that tourism growth had a corresponding economic growth in Taiwan [29]. Tourism had significantly contributed to the growth of the Turkish economy [30]. The output of the tourism industry in South Tyrol in Italy increased from less than 5% of the GDP in 1970 to 12% in 2007 [9]. Schubert et al. [31] used data from 1970 to 2008 in their investigation into the long-term relationship between international tourism incomes and the real exchange rate in Antigua and Barbuda. They found that growth of tourism demand resulted in a corresponding increase in economic growth and terms of trade [31]. Using a panel Granger causality analysis, Tugcu [4] studied the relationship between tourism and economic growth in European, Asian and Africa countries based on data obtained from 1998 -2011. The author found no causality between tourism and economic growth in Africa in contrast to result recorded for Asia and European countries [4]. In contrast, using nearly two decades data, a recent study has shown that tourism receipt positively impacted economic growth in Sub-Saharan Africa [32]. Tourism contribute to the balance of payment which is an important strategy to spur economic growth especially in developing countries [30].
Apart from tourism contributions to economic growth of nations, it could as well stimulate the growth of other sectors of a nation's economy [30]. For example, a recent study has investigated the link between economic growth and tourism related industries in the USA using data from 1998 to 2017 [33]. They found a long term relationship between two tourism influenced industries -lodging and food and beverage -and economic growth, indicating tourism triggered the development of these sectors [33].
As this current review has shown, the literature on tourism and economic growth is controversial with inconsistency in findings. Different factors could affect the tourism contribution to economic growth and other sectors. For example, a nation's economic structures such as the exchange rate could affect the benefit that could be realized from tourism. This has been reported for tourism in Brazil during big sporting events [34]. However, the work by Sánchez-Rivero and Cárdenas-García [35] has well documented the key factors that should be met before a country could realize economic growth from its tourism industry.

Social Impacts
Tourism does not only bring about economic benefits but also it can significantly contribute to the social development of a region [36]. Social development is a broad concept but its various definitions are centered on creating job opportunities, improving the quality of life and improving other social indicators [8]. Some scholars such as Fredline et al. [12] had argued that social impacts could be 'real' or 'perceived'. Real impacts can be assessed with a measurable outcome (e.g. traffic congestion) whereas perceived impacts are based on personal opinions [12]. Much of the literature on tourism social impacts has been based on community perception of both the negative and positive implications of tourism on host communities [12]. This section reviewed the positive and negative impacts of tourism on host communities or regions.

Positive Social Impacts of Tourism
Tourism could be regarded as positive if its earnings or the revenue generated are reinvested in infrastructural development and other related industries [24]. Indeed, a key indicator of tourism contribution to social development is improvement in infrastructure. For example, in the New Valley Oases in Egypt, there have been significantly expansion of hotel businesses due to tourism. The number of hotels grew from 7 hotels in 2003 to 16 hotels in 2007 and reached up to 29 hotels in 2009 [8]. Another study in South Africa by Mochechela [17] reported the rapid development of accommodation facilities due to the growth of tourism business. In Coles Bay -Freycinet in Australia, shopping, dining and recreational facilities were the positive infrastructural development of tourism development mentioned by local respondents [12]. Earnings from tourism is normally used to promote local development in destination regions. For example, a study in South Africa had earlier reported that 48.8% of respondents opinioned that revenue generated from the National Park was directed towards local infrastructural and educational development [17]. Tourism social impacts could also be manifested by improvement on the quality of life. Ayad and Ye [8] reported that tourism has significant positive impacts on local residents of Kharga in Egypt especially with regard to improvement on their quality of life.

Negative Social Impacts
A study in Coles Bay -Freycinet in Australia showed that about 30% of respondents mentioned increased traffic congestion, overcrowding in public areas, and noise as some of the negative social downside of tourism [12]. Tourism development led to the excessive use of the available community's services (67%) and traffic congestion (80%) on the Balearic Islands in Spain [20]. Congestion and resentment are well documented as social problems of tourism even in the 80s [24]. High price of food commodities especially in restaurants could be another negative impact of tourism on host communities as noted by respondents in the study by Tsundoda and Mendlinger, [22]. Similarly, Bestard and colleagues reported soaring price levels due to tourism in Spain [20]. Skyrocketing housing costs and rents because of tourists buying homes or property was reported as another social impact of tourism development [22].
Mochechela [17] documented 49.6% of respondents who stated that the Pilanesberg National Park in South Africa fueled high cost of living in the Park's vicinity. A study of equestrian tourism in national parks and protected areas in Iceland noted conflict and confrontation as the social impacts of tourism [37]. A recent study in Sierra Leone has shown that majority (52%) of the study participants associated tourism with high crime rate, drug abuse and prostitution [26]. In contrast, tourists' presence is not associated with an increase in crime rate in South Africa as reported by 51.6% of respondents [17]. In Trujillo, Honduras, cruise tourism had contributed to low crime rate because of government high expenses on policing and security [13].
Different groups in a tourism host community may have diverse perceptions of tourism impacts on their community and lives [22]. A study in Australia showed that the employment of locals or their relatives in tourism businesses could consequently influence their perception of the sector which is normally positive [12]. On the Greek island of Samos, local residents who were economically dependent on tourism had a more positive attitude towards the sector than those who were not dependent on it [38]. A study of locals in the Jiuzhaigou National Park in China showed the involvement of local residents in the tourism development of the park had significant benefits in their lives. This consequently results in the high positive perception of tourism impacts [39]. The diverse opinions of tourism impacts on a host community or region increase our understanding of the nature and degree of impacts created by the tourism industry [39]. This indicates that despite the positive economic impacts, its benefits are in most cases unevenly distributed especially among local people [40]. Mochechela [17] has argued that tourism could have negative implication on host communities if it is not properly planned. For example, the benefits of Cruise ship tourism were not realized in communities around Trujillo, Honduras because of lack of communities' involvement [13].

Socio-cultural Impacts of Tourism
Apart from the socio-economic and environmental impacts of tourism development, it can also contribute to the cultural dynamics in the host regions or communities [17]. The cultural impacts of tourism refer to the changes in the value systems, arts, traditional and customs local in the host communities [8,17]. Witt [41] asserted that impact of tourism on the host communities depends on the scale or magnitude of the differences between the host community and the coming tourists.
Tourism has rapidly grown in least developed countries (LCD) over the years which has increased the level of interaction between inbound tourism and indigenous peoples [27]. This interaction has yielded mix results especially in the areas of culture and tradition of host communities. Tourism bring different tastes and cultures in the host communities [22]. In South Africa 61.2% of respondents stated that the presence of tourists in their community had changed the lifestyles and values of the local population [17]. Similarly, a recent study in Sierra Leone has reported that 40% of the participants opined that tourism had negatively affected local norms and traditions [26].
Individual opinions may vary on tourism cultural impacts on host communities, and in some instances local people might be indecisive in their perceptions. For example, 40.5% of local residents in Kharga Oases could not simply decide whether or not tourism has changed their traditional culture [8]. Also, 12% of participant in a study in Sierra Leone gave a neutral response on tourism cultural and traditional impacts on host communities [26]. In Coles Bay -Freycinet in Australia, 35% of local residents indicated that they were happy with tourism but would like to see it discontinue [12].

Environmental Impacts of Tourism
The environment has been recognized as a valuable tourism resource; therefore, its protection is important for the long-term sustainability of the tourism industry [42]. Other scholars such as Dubois, [43] had acknowledged the environment as the 'raw material' supporting tourism development in the 21st century. Fredline et al. [12] argued that the recognition of the environmental in the tourism industry emanate from Agenda 21 which is a global policy document of the 1992 Earth Summit in Rio de Janeiro, Brazil.
Likewise other human activities, tourism impacts are not only visible on the economic and sociocultural sectors of a society but on the environment as well [44,45]. Economic activities and other related activities such as entertainment and shopping are the major factors contributing to tourism environmental impacts [46]. There are diverse environmental impacts of tourism but Briassoulis [47] had placed them into four distinct categories: "a) production-related impacts on resources; b) consumption-related impacts on resources; c) production-related residuals impacts; d) consumption-related residuals impacts" (p. 14) [47]

The Contribution of Tourism to Carbon Emission to the Environment
The tourism industry is a major consumer of energy [14]. The contribution of tourism to global CO 2 emissions ranged between 3.9% and 6.0% in 2005 alone. Out of this, it was estimated that a significant proportion (75%) account for travel and 40% were particularly due to air travel [48]. Early work showed that between 7% and 8% of documented greenhouse gas emissions in France were from tourists' transport [43]. In New Zealand the use of private vehicles for tourism purposes account for 3.4 Mt in carbon emissions [11]. There are other sectors in the tourism industry other than the transportation sector that contribute to carbon emission. For example, the use of energy in tourism services such as catering and accommodation can result in elevated level of CO 2 emissions which is not in conformity with sustainable environment and development [1].
There has been an increase in the use of time series data to model tourism environmental impacts. For example, Lee and Brahmasrene [49] studied the impact of tourism on economic growth and CO 2 emissions by utilizing data for European Union (EU) countries. They found that tourism has a statistically significant negative impact on CO 2 emissions. Another study used the environmental Kuznets curve hypothesis to investigate the effect of tourism growth of tourism development on carbon emissions in Cyprus [50]. The author used data dating back from 1971 -2010 and concluded that the influx of tourists between the investigated periods had a negative impact on carbon dioxide emissions [50]. However, there have been various initiatives and programs geared towards curbing the environmental impact of tourism. For example, in 2009, there was proposal to reduce tourism emission by 25-30% by 2020 and 50% by 2035 taking 2005 as the base year [51]. Larsen and colleague put forward a proposal that the adoption of slower travel modes could make tourism travel more environmentally friendly [52].

Other Environmental Impacts of Tourism
There are other environmental impacts of tourism apart from carbon emission. Other researchers had identified environmental damage and disruption as the negative environmental impact of tourism in Australia [12]. A study in the New Valley area (Kharga Oases in Egypt) investigated people's perception of tourism environmental impact. They found that noise and pollution account for 31%, whereas the destruction of the environment due to building of tourist facilities account for 50.9% [8]. Tourism could disturb aquatic ecosystems by diverting natural water bodies to support tourism activities [53]. Another study on Mount Huangshan and Mountain Resort of Chengde in China showed that soil compaction and vegetation damage were some of tourism environmental impact [53]. However, Briassoulis [47] questioned some of the environmental impacts often associated with tourism in the literature. The author, argued that natural and artificial resources are used by both tourists and locals, thus separating impact that arise from tourism alone and those from locals is a critical challenge [47].
The environmental impact of tourism could also depend on the type and scale of tourism in a region. For example, Schmudde reported that loss of vegetation and wider trails were among the notable environmental impact of equestrian tourism in Iceland [37]. However, Hitunen [54] found that the environmental impact of 'second home tourism' in Finland were insignificant because "production of waste can be minimal, recycling of waste optimal and consumption of energy and water low" (p. 251) [54]. Cruise tourism increased the environmental burden on communities near the cruise port in Trujillo, Honduras [13].
People's perception of tourism environmental impacts could depend on their involvement in the industry, and the level of environmental awareness and understanding. For example, Bestard and Nadal [20] reported that tourism was viewed by the general population as a main contributor to environmental destruction on the Balearic Islands. Using the confirmatory factor analysis (CFA) model, Assante and colleagues studied resident attitude toward tourism in Oahu, Hawaii, USA. They found that residents strongly supported the notion that tourists generate more wastewater than residents [40]. Nyaupane and Thapa [55] investigated local residents and workers perceptions in a tourist site -the Annapurna Conservation Area Project -in Nepal. They found that about 61% of managers opined that tourism contributed to solid waste management problems in the area whereas 7% of local residents shared the same view [55]. In terms of deforestation, 43% of the managers perceived that tourism is responsible for deforestation in the study area, while 2% of local residents have the same view [55]. Assante et al. [40] asserted that as soon as environmental degradation and other visible impacts outweigh other benefits normally derived from tourism such as employment, attitudes towards tourism will change negatively. Tourism developments have the potential to generate both negative and positive impacts so any approach must be able to take positive impact into account [42]. For example, an increase in environmental awareness (97.8%) and the protection of 'environmental assets' (97.1%) were noted by residents as the environmental impact of Lake Bosomtwe Basin -a tourist site -in Ashanti region, Ghana [56]. In a study in Nepal, local residents stated that tourism had increased environmental awareness (94%) and forest conservation (90%) [55].
Tourists themselves can contribute to the environmental impact of the tourism industry. There is an array of reasons for tourists to directly contribute to the environmental problems in a host community. One of these is the diversity in the tourist's characteristics [46]. For example, Kim and colleague investigated the environmental attitudes of tourists who speak 'weak and strong future-time-reference (FTR)'. They found that language positively influenced the environmental attitude of tourists who speak a weak FTR language (Mandarin) as they exhibit high pro-environmental attitude compared to those tourists who speak a strong FTR language (Korean) [57]. Also, the strength of environmental laws and policies of the tourist's country of origin could influence their environmental behavior and attitude. This has been exemplified in a study of German, Russian and Turkish tourists in central Kemer, Antalya in Turkey. The author found that Germans were much more aware of the environmental impact associated with tourism than their Russians and Turkish counterparts, largely due to the environmental regulations of their respective countries of origin [58].
There have been global efforts to mainstream environmental awareness in the tourism industry. For example, the International Festival of Environmental Film and Video (FICA) held in Goias city, Brazil is one the initiatives that promote environmentally friendly tourism events [59].

Conclusion
The current review has shown that tourism development can contribute to positive sociocultural benefits such as cultural exchange, opening up of new areas, improvement in the standard of living and quality of life in host regions. Despite its positive contributions to host regions, it has some negative impacts on local communities. For example, the influx of foreign tourists could undermine the existing tradition and belief systems in destination regions. It could also increase crime rate in some cases, and other social problems such as prostitution, gambling, congestion in public infrastructures. Tourism has enormous economic impacts on tourism dependent nations or communities. It could boost economic growth, provide employment opportunities, and stabilizes the balance of payment. However, it has some economic disadvantages in host communities. For instances, it leads to increase in the prices of local commodities, and high cost of living. Furthermore, the current review has shown that tourism industry has some positive benefits such as the conservation of forest that support wildlife development. Nonetheless, it has many negative environmental implications such as greenhouse emission, deforestation, and littering. The environmental impact of tourism however depends on the type and scale of tourism activities practice in a particular destination.
Tourism could either be beneficial or destructive to the host communities [17]. Therefore, tourism development policies should involve local residents in host communities [20]. The tourism industry could be beneficial to indigenous host communities if the earnings are reinvested in local development projects [24]. It is recommended that future research should focus on the ways of promoting environmentally friendly tourism in host regions. Future review studies should focus on sustainable tourism in destination regions.