Sentinel landscapes

Site selection

South-West Mau site, Kenya
Situated in Bomet county in the Rift Valley of Kenya, the South-West Mau is one of the 21 gazetted forest blocks that make up the Mau Forest Complex, the largest and most important of the five water towers of Kenya.
The Mau Forest is the largest closed‐canopy montane forest ecosystem in East Africa, and prior to recent deforestation it was larger than Mt Kenya and the Aberdares forests combined.
Hydrology: The South-West Mau catchment area is the source of the Sondu Miriu River, which then feeds into Lake Victoria. It is arguably of transboundary significance as the water that flows from it is part of the Lake Victoria catchment, which in turn provides water to the Nile River.
Elevation: The South-West Mau falls within an altitude of 1,800 to 3,000 m asl.
Temperatures: Temperatures range from 16° C to 24° C.
Rainfall: Rainfall patterns generally follow altitude. The annual average rainfall ranges between 1,000 mm and 2,000 mm.
Inhabitants: The forest was traditionally inhabited by the Ogiek people, who were hunter-gatherers, but the adjacent area is currently dominated by the Kipsigis subgroup of the Kalenjins, and other settlers, namely the Kikuyu, Luhya, Luo and Kamba.

Key economic activities: Environmental services provided by the South-West Mau Forest support key economic sectors, including energy, tourism, agriculture (cash crops, subsistence crops, and livestock) as well as water supply to urban centers and industries. The main cash crop in South-West Mau is tea. Subsistence crops grown include maize, millet, potatoes, bananas and vegetables.

Dominant vegetation types: Typical tree species in the Mau Forest include Pouteria adolfi-friedericii, Strombosia scheffleri and Polyscias kikuyuensis. Olea capensis, Prunus africana, Albizia gummifera and Podocarpus latifolius are also found here.

Drivers of tree cover change: Over the last decades, approximately 25% of the Mau Forest has been lost to excisions, encroachment and illegal logging. In 2001, 27.3% (22,797 ha) of the South-West Mau Forest underwent excision. Other key threats to the South-West Mau Forest have been illegal extraction and unsustainable use of forest resources for commercial purposes, especially timber, wood fuel and charcoal, cattle grazing and land resettlements. Continued destruction of the forest has not only led to biodiversity losses, but also total disruption of rain patterns and other changes in micro climate. Serious water crises have been experienced in some areas, whereby perennial rivers are becoming seasonal, storm flow and downstream flooding are increasing, and in some places the aquifer has dropped by 100 m while wells and springs are drying up.

Mt Elgon site, Uganda
The Mt Elgon site is located in the Mt Elgon subregion of eastern Uganda. It falls in three districts, namely Sironko, Mbale and Bulambuli. Mount Elgon is a massive solitary volcanic mountain on the border of eastern Uganda and western Kenya. The mountain’s highest point, named “Wagagai”, is located entirely within Uganda. It is vast, measuring 80 km in diameter. It is the seventeenth highest mountain in Africa.

Hydrology: Mt Elgon (Uganda) is the catchment area for many rivers that drain into lakes Victoria and Kyoga that also feed the Nile River.
Elevation: The site has two major topographic zones: lowlands and a mountainous upland. The altitude of inhabited zones varies between 1,100 and 2,500 m. The highest areas lie within the Mt Elgon Forest National Park. Mt Elgon consists of four major peaks, three of which are in Uganda, the highest (Wagagai) is at the Uganda-Kenya border (4,321 m).
Temperature: Temperatures range between 15° C and 23° C.
Rainfall: This area has bimodal rainfall patterns, with its annual rainfall being between 1,270 mm and 1,500 mm.
Inhabitants: The Mount Elgon area is home to two major tribes, the Bagisu and the Sabiiny.

Main economic activities: A majority of the population is engaged in subsistence farming as their main economic activity. Accordingly, the available land is subject to continuous and intensive cultivation. At lower areas, important crops grown include maize, millet, cassava, sweet potato, rice and vegetables, while at a higher elevation, coffee-banana systems dominate. In the transition zone, there is a mixture of both. Coffee is the major cash crop. Most households own livestock, usually kept in a zero grazing system or in combination with partial grazing (tethered grazing, stubble grazing).

Dominant vegetation types: The lower and mid-highland areas of the Mt Elgon site are intensively cultivated with little to no remnants of natural vegetation. Natural vegetation is mainly restricted to gazetted areas at higher elevations – the Mt Elgon Forest National Park and some smaller forest reserves, e.g. Namatale. The national park supports a variety of unique habitats (montane forest, bamboo forest, grassland, heath and moorland). The mountain slopes are covered with olive, Olea hochstetteri and Aningeria adolfi-friederici wet montane forest. At higher altitudes, this changes to olive and Podocarpus gracilior forest, and then a Podocarpus and Arundinaria alpina (bamboo) zone. Higher altitudes comprise the Hagenia abyssinica zone.

Drivers of tree cover change: The main drivers of tree cover change are encroachment and the establishment of smallholder subsistence agriculture along the slopes of Mt Elgon. Encroachment is driven by the pressure of a high population and the prevalent political climate. Farmers mainly use slash and burn techniques to prepare land for cultivation and those close to the national park are reluctant to adopt appropriate farming and soil conservation practices due to the uncertainties surrounding their future on such plots. Slash and burn techniques are known to accelerate landslides and various forms of soil erosion including rills, gullies and sheet. There was minimal encroachment and tree cover and land-use change between 1960 and 1995. However, the period between 1995 and 2006 marked a significant loss of woodland and forest cover, particularly on steep concave slopes (36o–58o) within the national park. Deforestation on Mt Elgon was reported to have had both onsite and offsite implications, such as climate variability, drought, heat waves, flash floods, economic dislocation, crop failure and associated malnutrition in surrounding low-lying areas.

Gishwati site, Rwanda
The Gishwati landscape comprises a protected forest reserve and agricultural landscapes in Rubavu, Rutsiro, Nyabihu and Ngororero districts in the northwestern part of Rwanda, not far from Lake Kivu. The Gishwati forest is used for the conservation of animal species that are threatened or endangered. These are eastern chimpanzees (Pan troglodytes schweinfurthii, listed as threatened on the International Union for Conservation of Nature [IUCN] Red List); golden monkeys (Cercopithecus mitis kandti, listed as endangered); mountain monkeys (Cercopithecus l’hoesti, listed as vulnerable); and more than 130 species of birds including 14 that are endemic to the Albertine Rift.

Hydrology: Gishwati is the catchment area for many rivers, including the Sebeya and Busoro rivers, which empty into Lake Kivu.
Elevation: Altitude ranges from 1,800 to 2,700 m asl.
Temperature: Depends on the altitude and ranges from 14° C to 26° C.
Rainfall: The climate is bimodal, with a mean annual rainfall of 1,660 mm.

Main economic activities: These include farming, ranching, tourism, hydroelectric power generation and fishing (Lake Kivu). Agriculture is the main economic activity in Gishwati. In this mixed crop-livestock system, the main crops grown include Irish potatoes, climbing beans, maize, sweet potatoes, millet, sorghum, banana and vegetables such as carrots and cabbages. The main cash crops are tea, coffee and wheat.

Dominant vegetation types: The native forest remnant is dominated by Macaranga kilimandscharica, Carapa grandiflora, Entandrophragma excelsum, Symphonia globulifera, Hagenia abyssinica, Polyscias fulva, Dombeya goetzenii, Euphorbia candelabrum, Ficus thonningii and Erythrina abyssinica. The rehabilitated forest (at the periphery of the native forest) and inhabited areas are dominated by Alnus acuminata and diverse Eucalyptus species including Eucalyptus globulus

Drivers of tree cover change: The Gishwati forest used to extend west beyond Lake Kivu, connecting with the rainforests of the Congo, and south connecting with the Nyungwe Forest. The reserve’s forests were largely intact in 1978, and substantial forest cover still remained in 1986. The forest has a history of deforestation extending over the past 50 years, partly because of large-scale cattle ranching schemes, free grazing of cattle, crop farming, human settlements, and the establishment of plantations of exotic tree species mainly Pine, Eucalyptus and Acacia spp.

However, during the Rwandan Genocide in 1994/1995, a wave of refugees arrived in the Gishwati forest and began clearing it, often for subsistence farming. The Gishwati forest reduced in size from 28,000 ha in the 1970s to about 600 ha in 2002, implying a significant loss of area and biodiversity. By 2001, only a small circular patch of native forest remained, 1,500 acres (6.1 km2) of the forest’s original 250,000. Reforestation efforts in the past few years have increased the remnant native forest to about 2,500 acres (10 km2). Large tea estates occupy the central and northern parts of the reserve. In addition to a tremendous loss of biodiversity, the area around Gishwati is plagued with flooding, landslides, erosion, decreased soil fertility, decreased water quality, and heavy river siltation, all of which aggravate local poverty and environmental degradation.

Eastern Democratic Republic of Congo
This sentinel site is located at the periphery of Virunga National Park in the province of North Kivu in the east of the Democratic Republic of Congo, stretching along the Ugandan and Rwandan borders. The park has a very diverse and unique landscape with exceptional fauna and flora of global importance for conservation and was classified as a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site in 1979. It covers an area of over 784.368 ha in the Albertine Rift and lies at the intersection of several biogeographic zones. It forms an important water catchment area for Lake Kivu.

Hydrology: Lake Kivu is a transboundary lake that lies on the border between the Democratic Republic of the Congo and Rwanda, and is in the Albertine Rift, the western branch of the East African Rift. The hydrographic network comprises two major lakes – Lake Kivu empties into the Ruzizi River, which flows southward, drains into Lake Tanganyika and feeds into the Congo Basin and Lake Edward, then draining into Lake Albert and feeding into the Nile Basin. It also has four middle lakes (Monkoto) and important rivers such as Rutshuru, Rwindi, Semliki, Osso and Lowa.

Elevation: The landscape located in the North-Kivu province has a varied and hilly relief configuration that encompasses:
Mountain chains (3,000-5,000 m asl) (Rwenzori glaciers [5,105 m asl])
Volcano mountain massifs: Nyiragongo (3,470 m asl), Nnyamulagira (3,056 m asl), Karisimbi bordering Rwanda (4,507 m asl)
Albertine rift valleys of Lake Edward (912 m asl) and Lake Kivu (1,460 m)
Mitumba and Bishusha massifs
Lowland plains (700-1,000 m asl)
The lake itself covers a total surface area of some 2,700 km2 and stands at a height of 1,460 m above sea level.

Temperatures: Temperatures are strongly correlated with altitude – in the lowlands (under 1000m), the temperature averages 23° C; at 1,500 m they average around 19° C, and at 2,000 m around 15° C.

Rainfall: The climate of North Kivu is bimodal, alternating two rainy seasons with two dry seasons, differing in their timing on the two sides of the Equator. Average annual rainfall is between 1,000 and 2,000 mm.

Dominant Vegetation Types: The main vegetation types occurring across the North-Kivu province are:
Savannahs in the alluvial plains of the Semliki and Rutshuru
Sclerophyll forests in the lava plains north of Lake Kivu
Montane forests in the Rwenzori and Virunga massifs
Equatorial forest in Lubero, Masisi and Beni

Main economic activities include: Crop and livestock farming, tourism, fishing, hydroelectric power generation, mining of precious stones (such as gold, diamond, silver, monazite, pyrochlore, casserite, phosphate, coltan, wolframite and zirconium). The periphery of the park is densely populated with poor farming communities. The majority (80%) of land outside of protected areas is used mainly for subsistence rain-fed agriculture, but also includes coffee, tea, cocoa and pyrethrum, and large cattle ranches. The most important staple food crops produced in North Kivu are cassava, plantain, Irish potatoes, beans, maize and sweet potatoes and the most commonly traded crops are maize and potatoes, vegetables and fruit tree crops, but a range of different vegetables are grown in North Kivu (cabbage, onions, carrots, taro, leeks, tomato and eggplant).

Drivers of tree cover change: The North Kivu region has had a history of recurrent troubles and instability since the 1960s but these culminated from the early 1990s onward with the proliferation of local-level rebellions and international armed conflicts. In 1994, the threat escalated severely following the Rwandan genocide when almost 1 million war refugees settled in large camps on the periphery of the park, which led to the destruction of the park’s vegetation and natural resources. The humanitarian and environmental crisis in the area continued with two consecutive civil wars that took place between 1996 and 2003 and the collapse of the central government in Kinshasa seriously depleted the natural resources and capacity of the park management authorities. Currently, the area is highly degraded, thereby threatening the livelihoods of communities that depend on the park and Lake Kivu for survival.

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