The impacts of tourism include its effects on the environment, destination countries, and its economic contributions. It has been a part of tourism discourse since the 1970s, with increased attention in recent years due to controversies over overtourism. It is not easy to categorize impacts, as they contain both direct and indirect elements. Tourism is typically seasonal, and its effects only become apparent over time, with varying impacts at different stages of development.
Tourism impacts fall into three basic categories. Environmental impacts affect an area's carrying capacity, vegetation growth, air quality, water bodies, groundwater levels, wildlife, and natural phenomena. Sociocultural impacts relate to interactions between people of different cultural backgrounds, attitudes and behavior, and relationships with material goods. Tourist arrivals in sensitive areas can be harmful, causing the loss of indigenous cultures, or, conversely, contribute to the preservation of cultures and cultural sites by increasing resources. Economic impacts are usually viewed as positive, contributing to employment, better services, and social stability. Cultural education may also improve, but this can be overlooked. However, these impacts can contribute to higher living costs within the community, driving away local businesses and increasing costs for local residents.
Environmental Impacts
Ecotourism, nature-based tourism, wildlife tourism, and adventure tourism occur in environments such as rainforests, alpine and wilderness areas, lakes, rivers, coasts, and marine environments, as well as in rural villages and coastal resorts. Human destinations are increasingly moving toward the few remaining natural and clean environments on the planet, driven by their desire for authentic and exciting experiences. The positive impact of this can be increased awareness of environmental management, while the negative impact can be the disruption of the very experience people seek. There are direct and indirect impacts, immediate and long-term impacts, and near- and long-term impacts on the tourist's destination. These impacts can be divided into three categories: the impact of services, tourist activities, and transit impacts.
Service Impacts
Service impacts occur when a region moves from the "exploration" phase to the "participation" phase and then to the "development" phase of the tourism area's life cycle. During the latter period, both direct and indirect environmental impacts can be manifested through the construction of superstructure such as hotels, restaurants, and shops, and infrastructure such as roads and electricity. As a destination evolves, more tourists seek experiences, and their impacts increase. Demand for water for bathing, waste management, and drinking increases. Tourist demands can lead to river diversion, over-extraction, or pollution. Noise pollution can disturb wildlife and alter behavior, and light pollution can disrupt feeding and reproductive behavior of several species. Power supply via diesel or gasoline generators causes additional pollution and noise. General waste and litter are also a result of services. Food and beverage consumption increases with the arrival of more tourists, which in turn creates plastic and non-biodegradable product pollution.
Tourist Activities
Virtually all tourism activities have an ecological impact on the host destination. The local environment in rural destinations is most often impacted by activities such as hiking, trekking, canoeing, birdwatching, wildlife safaris, surfing, scuba diving, and snorkeling.
Hiking and camping have a range of direct impacts on the activity area. The most obvious impacts are erosion and compaction of roads due to daily use. With the presence of obstacles such as downed trees and water puddles, roads are widened or informal routes are created to circumvent obstacles. Other direct impacts include damage or removal of vegetation and loss of height, reduced leafy areas, erosion of tree roots, migration of trampled plants, and introduction of non-native species. Indirect impacts on roads include changes in soil porosity and microbiome composition, problems with seed germination and dispersal, and a decline in soil nutrient composition.
With many hikers and trekkers going on multi-day trips, a significant number of people camp for short periods, either at formal campsites or informal campsites. Similar impacts on campsites include soil compaction, formation, and erosion, damage to vegetation and foliage, and additional campfire-related issues. Informal trails are created around the campsite to collect firewood and water, and trees and saplings can be trampled, damaged, and cut down for burning. The heat from campfires can damage tree roots. In formal campsites, tent pitch areas are naturally devoid of vegetation, while informal camping can damage sensitive plants and grass during a short overnight stay.
Like most recreational activities, camping and hiking can generate waste, such as food scraps and human feces. The familiarity of the wilderness with human contact and unfamiliar food sources can have a detrimental impact on the wilderness and pose risks to humans. Taking precautions to accumulate, collect, and remove waste will also have a direct impact on the local environment.
Tourism can act as a powerful force for the spread of non-native species. Human activity increases with tourism and is concentrated in certain local natural regions, especially protected wildernesses and parks. Due to increased human visitation from many different geographic regions, a higher prevalence of non-native species is observed in these areas. Traditional recreational activities such as hiking, biking, and off-roading can disturb fauna habitats, increasing the spread of invasive species and harming natural ecosystems. Nature-based tourism (such as wildlife viewing and outdoor recreation) is believed to be on the rise, typically occurring in undisturbed and pristine environments. With human-induced disturbance, suitable open margins may exist, allowing non-native species to establish themselves and exploit the new availability of resources. This can have disastrous consequences for native plants and animals, as invasive animals often successfully colonize disturbed areas where native plant and animal communities have been disturbed or even damaged.
Examples of invasive species spread through tourism:
- The big-headed ant (Pheidole megacephala): One of the worst invasive species and ranked among the "world's 100 worst" invasive species. It was originally found in the Galapagos Islands in 2007 on a tourist cargo ship. The ants can be transported as humans move from island to island.
- The staghorn ant (Bromus tectorium): It spreads rapidly, preventing native species from growing, and can cause rapid wildfires. People can carry it in their shoes and gear; pets and other animals can also spread its seeds as they travel.
- The zebra mussel (Dreasena polymorpha): It is believed to have come from the Caspian Sea in Europe in the ballast water of a ship. It spreads via unsanitized boats from one body of water to another as tourists travel to different locations.
There are ways to reduce the spread of non-native species, such as being careful to remove seeds from shoes and trousers after hiking or biking. There are other ways one can reduce the impact of invasive species on local environments such as cleaning the entire boat when moving from one body of water to another and making plans to manage routes.