Course:GEOS303/2023/Malawi

Introduction

National flag of Malawi

Malawi is a landlocked country situated in the South East of Africa, bordering the nations of Mozambique, Zambia, Tanzania. It has a total land area of 118,480 km². It is known for its remarkable highlands and expansive lakes. The country stretches along a narrow, curved strip of land within the East African Rift Vallet, with Lake Malawi (also known as Lake Nyasa or Lago Niassa) predominately taking up the North East of the country and forming more than one-fifth of its total area. Lake Malawi has a total surface area of approximately 29,600 km² and is home to a wide range of biodiversity. As of January 2021, Malawi has a population of approximately 19,431,566, with Lilongwe as its capital and largest city.

Map and location of Malawi

Climate and biomes

Malawi is characterized by a diverse climate and rich biomes. The country's climate is predominantly tropical continental, with distinct wet and dry seasons. The wet season typically extends from November to April, influenced by the Inter-Tropical Convergence Zone (ITCZ), while the dry season spans from May to October. The wet season accounts for about 95% of the annual precipitation. Malawi's climate is also modulated by altitude, with cooler temperatures prevailing in the highlands of the nation. The annual average rainfall varies across different regions, with Lilongwe receiving about 900 mm and Zomba 1,433 mm. The low areas such as the Lower Shire Valley are particularly vulnerable to floods.

The climate in Malawi is influenced significantly by the ITCZ. This climatic feature is driven by tropical high-pressure belts over the Indian and Atlantic Oceans and the Congo Air Boundary (CAB), impacted by sea surface temperature anomalies such as the Indian Ocean Dipole and the El Niño/Southern Oscillation system. Local differences in rainfall are influenced by Malawi's complex topography, which causes deflections of moisture-bearing winds responsible for precipitation and creates rain-shadow effects in various terrains.

The country's predominant biomes include the Central Zambezian Miombo Woodlands, Lake Malawi eco-region, Southern-Rift Montane Forest-Grassland Mosaic, and Eastern Miombo Woodlands.

Central Zambezian Miombo Woodlands

This eco-region, part of the tropical and subtropical grasslands, savanna, and scrublands biome, covers large portions of the Western and Northern Malawi. It experiences annual precipitation between 550-1700 mm (November to March) and temperatures ranging from 9°C to 30°C. The Miombo Woodlands are characterized by tall Miombo trees and support a rich biodiversity.

Lake Malawi

Lake Malawi is a freshwater eco-region that is part of the Great Lakes system, and is characterized by diverse geography including small islands, inlets, bays, and reefs. The Lake's ecosystem is rich in species such as cichlids, lake sardines, and supports larger animals such as hippopotamus and Nile crocodiles.

Southern-Rift Montane Forest-Grassland Mosaic

Located in the montane grasslands and shrublands biome, this eco-region is situated in the Northern and Eastern shores of Lake Malawi. It consists of a network of mountains and plateaus, with a diverse range of flora and fauna.

Eastern Miombo Woodlands

The Eastern Miombo Woodlands is also part of the tropical and subtropical grasslands, savanna, and shrublands biome. These woodlands feature rolling hills and valleys. This region is home to a variety of wildlife, including African elephants and numerous bird species.

Diversity

Mulanje Mountain in Malawi

Biodiversity in the country of Malawi is largely aquatic, due to its unique lake evolutionary history. Because Malawi is located in the tropics and has many different biomes biodiversity does range significantly outside of just aquatic systems, but scientific recording of aquatic biodiversity has been disproportionately pronounced for reasons that will be stated. Along with the Lakes, Malawi consists of mountains such as Mulanje Massif, with varying altitude ranges. Differences in altitude mimic difference climates along latitudes, as described by Alexander von Humboldt. This means many different species confined to their own biomes are separated by abiotic factors not found on uniform land, such as drastic temperature differences. This leads to a high amount of biodiversity as seen in species counts of the country.

As discussed, the most famous and relevant form of biodiversity in Malawi is aquatic, which is ironic due to Malawi as a county being landlocked and not near the rich in biodiversity oceans surrounding the African coastline. the cause of this being Lake Malawi. Forming due to the east African rift, lake Malawi became a biodiversity hotspot starting around 5 million years ago. While niches formed from the lake topography itself, generating many species of flora and fauna around the lake, the true biodiversity is from the fish within the lake. The surrounding biodiversity is from the habitat and nutrients the lake directly and indirectly provide. Crocodiles, hippopotamus, fish eagles, and monkeys are some of the many species that benefit from Lake Malawi. There is a significant dry season in Malawi, thus the biodiversity found the lake is a result of animals finding refuge and resources. While heavily studied, lake Malawi remains the most intriguing case of adaptive radiation. the cichlid family, a family that resides in the lake has been known to rapidly speciate. The patters of speciation in Lake Malawi over time has close correlation with the nutrient composition of the lake. Since nutrients have always been relatively low in lake Malawi due to the climate and surrounding terrestrial areas of the lake, surviving in the lake is difficult. The cichlid have thus found different resource niches that are very similar but non-conflicting, thus allowing the fish to sympatrically speciate. This sympatric speciation is the cause for much of the aquatic biodiversity trends through time in Lake Malawi.

The land areas of Malawi are also host to immense biodiversity due to the differences in climate. Mainly comprised of woodlands and grasslands, ample area are in place for typical southern Africa fauna such as elephants and rhinos to flourish. Malawi is home to a number of national parks, which makes the implementation of conservation much easier and supported. This means that the biodiversity found in these savannah plains and forested areas are generally protected. Bird species, while not as pronounced as the fish, also harbor immense biodiversity. 683 recorded bird species are found in Malawi, with only 1 being endemic. Much of this diversity is found in the Malawi forests which make up around 36% of Malawi's land area. Much like the Andes mountains in South America, the altitude changes discussed earlier also leads to mass amount of bird diversity, which is another reason behind the number of bird species found in the area.

Andinoacara rivulatus, a species of cichlid found in Lake Malawi. It's bright coloration indicated that it spectated as a result of sexual selection and less as a result of maximizing resources.

Across taxa diversity is extremely abundance in Malawi, this is due to factors such as the latitudinal gradient of biodiversity, considering that Malawi is near the equator, but it also has to do with Malawi's specific natural resources. Lake Malawi along with the many terrestrial biomes found present an opportunity for intense diversification.

Human influences

Historical Role of Humans

Traditional farming practices, namely subsistence cultivation, has had a profound impact on ecosystems in Malawi. Although these practices may have been sustainable in the past, population growth and an increase in farming intensity have led to deforestation and soil degradation. Without proper crop rotation practices and frequent cultivation, soil degradation has become a prominent issue throughout the majority of Malawi's land. These generally poor farming practices have historically been exacerbated by the introduction of cash crops, especially during European colonization. Expanding into cash crop production such as tobacco, coffee, and tea has had a worsening effect on the already struggling soil quality and has been shown to have a direct contribution to the deforestation of nearly 33,000 hectares of land every year. Further, the high demand for wood as a fuel source is another contributing factor to deforestation. In 1990, it was estimated that 8.5 million cubic meters of wood were used in Malawi, with 82 percent of the total being used for wood fires in both rural and urban residential homes, contributing to the strain on local forests and the health of Malawi's forest ecology.

Extent and Nature of Human Influence

The large-scale conversion of natural landscapes and ecosystems into agricultural land and urban developments has fragmented ecosystems in Malawi. These disruptions in forest continuity have shown to reduce the biodiversity of ecosystems. For example, in a study that compared gamma diversity of frogs across intact Miombo forests, secondary forests, and eucalyptus plantations, it was clear that intact Miombo forests contained the highest diversity values. Unfortunately, with the volume of Malawi's logging industry and the effects of irresponsible farming techniques, degraded and disrupted habitats are becoming increasingly common.

Researchers in Malawi have identified up to 69 invasive species that threaten the biodiversity of local ecosystems. These species were introduced anthropogenically, likely by food imports or recreation. In a study done in Malawi's Nyika National Park, invasive plant species had the greatest presence on the park's peninsula, where they were shown to decrease biodiversity by decreasing the growth rate of native species.

Observed and Future Impacts on Biodiversity

Some species in Malawi have become extinct or are already on the endangered species list as a result of human influence on the environment. Malawi's national tree, the Mulanje cedar, is listed as an endangered species due to logging and invasive species. Similarily, the Chapman’s pygmy cha- meleon has been identified as being critically endangered. Its natural habitat is in the low elevations of the rainforests of the Malawi Hills, of which 80 percent has be deforested since 1984. If these high profile species are any indication, anthropogenic pressures in Malawi pose a serious threat to biodiversity in the future. Many of the communities in Malawi depend on the local ecosystem services for their livelihood, using the land for agriculture, hunting, fishing, and biomass fuel. A loss of biodiversity poses a threat to their livelihood if remediation is not considered. From an Aquatic standpoint, fisheries have experienced depleted populations in Lake Malawi. Cichlids, a keystone aquatic species, have suffered as a result and their biodiversity is rapidly declining. As one of the most populated southern African countries, and having one of the highest population growths, the environment has taken a toll.

Conservation

Fishing In Lake Malawi

Lake Malawi Fish Conservation Project

Lake Malawi National Park is located on the southern end of the lake. It was established in 1980 and designated as a World Heritage site in 1984. Hundreds of fish species, mostly endemic, live in this national park. The aquatic ecosystem of Lake Malawi is increasingly threatened by human activities, such as overfishing and land use change. Many fish that live in this lake are classified as critically endangered or threatened. Many people living near the lake rely on the fish for their food security and livelihoods. Increasing population of locals have led to unsustainable fishing practices in the lake. The conservation project aims at improving the state of conservation in the Lake Malawi National Park. The actions being used to achieve this goal are sustainable co-management of the fish resources in partnership with the local communities; Higher numbers of management authorities; Empowering communities to enforce bylaws that support conservation; Improved fish and ecological  monitoring with support of research institutions; and improved working relationships among all parties involved. This conservation project has adequately increased Beach Village Committees and more authority enforcing the bylaws. This has led to more confiscation of illegal fishing gear and nets. The project successfully protected fish breeding areas leading to higher populations of fish. Food insecurity and poverty rates have lowered due to the restoration of fish populations.

Reforestation and Natural Tree Conservation Project

Tree Nursery

Rates of deforestation in Malawi are one of the highest in the world. Deforestation creates land degradation which affects the viability of local communities and habitat of ecosystems. Deforestation is proceeding northwards across Malawi threatening the Nkhata Bay District. Ripple Africa created a large reforestation project covering 4,000 square kms allocated by local chiefs. 4 million trees will be planted by locals in community tree nurseries each growing 3,000-6,000 trees. The trees planted include fast growing species for wood fuel and timber. They also include Indigenous hardwood and fruit trees that will be used to re-establish forest cover, maintain the soil and water courses, and provide livelihood opportunities for local communities. The project also aims to increase marketing of fuel efficient wood burning stoves in order to decrease the use of local forest resources, along with education and training in community forest resource management, composting and other sustainable land use practices. The project has changed over 40,000 households to fuel efficient cookstoves. Since the project began in 2006 over 5 million trees have been planted helping with deforestation rates in Malawi.

Water For People In Malawi

Hauling Water In Malawi

Water for people began working in Malawi in 2000. Malawi has a population of 18.62 million. In Malawi 65 percent of people living in rural communities have access to basic water services and only 25 percent have access to basic sanitation services. The goal of the project is to help Malawians bring water, sanitation and hygiene to their communities. Water for people drills and repairs boreholes and rehabilitates gravity fed piped water systems to expand water access in Malawi. Water for people is increasing coverage of sanitation services through a community led total sanitation model. They also inform people on the dangers of open defecation, encouraging switching to better and safer toilets. In schools, Water For People increases access to water and sanitation facilities and promotes good hygiene practices among students. This project has become a leader in Malawi’s water and sanitation sector. It has been replicated all over Malawi providing many communities with clean drinking water and safe sanitation.

Elephants in Malawi

Elephant Relocation Project

Rangers in Malawi are taking on the task of moving hundreds of elephants into safer national parks. The animals have suffered a sharp decline in recent years due to poaching and loss of habitat. The project aims to move 500 elephants to a new home in Malawi securing the future for Malawi’s elephants. The 500 elephants were moved to Nkhotakota Wildlife Reserve. Higher numbers of law enforcement and reliable perimeter fencing were added to the park ensuring the safety of the elephants in their new home. Consultation with local communities was held to decrease human-wildlife conflict. Nkhotakota once had more than 1,500 elephants but due to poaching fewer than 100 remained when African Parks assumed management of the reserve. Thanks to the movement of over 500 elephants and 2,000 other animals this once near-empty forest is alive with the sounds of a growing elephant herd. Tourism has been increased by this project and the births of new calves have been documented in Nkhotakota.

References

This Tropical Ecology Resource was created by Course:GEOS303.