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14.1: Human-Dominated Landscapes

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    In every country on Earth, significant portions of unprotected lands still harbour some of their original biota (Figure 14.1). Consider, for example, remote regions that are considered “wilderness” by governments and the general public. Most of these areas are inhabited by low-density human societies that practice a traditional way of life. With relatively little outside influence from modern technology, these traditional peoples are often dependent on—and thus highly concerned with—the health of their environment. More importantly, traditional peoples have been an integral part of their environments for thousands of years. The present mixture and relative densities of wildlife in these “wildernesses” thus reflect the historical activities (e.g. fishing, hunting, fire management, land clearing, and planting of useful plant crops) of the people living in those areas (Roberts et al., 2017). These activities do not degrade the environment if human population densities remain low and natural resources are harvested sustainably. To regulate these activities, most traditional societies have an established system of rights to natural resources, known as customary laws, which an increasing number of governments recognize (Section 12.2.2). Conservation biologists should follow this example: rather than being considered a threat to the “pristine” environments in which they live, traditional peoples should be seen as important partners in conservation efforts because protecting their lifestyles also ensures the protection of biodiversity (Box 14.1).

    Traditional peoples are important partners in conservation efforts because protecting their lifestyles also ensures the protection of biodiversity.

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    Figure 14.1 Vertebrate species richness in a variety of land-use systems in West Africa. As human impacts increase, the average number of forest species generally declines while open-habitat species increase. After Norris et al., 2010, CC BY 4.0.
    Box 14.1 Traditional People and Conservation: Turning the Page

    Abraham J. Miller-Rushing1 and John W. Wilson

    1Acadia National Park, US National Park Service,

    Bar Harbor, ME, USA.

    How can we balance the conservation of biodiversity with the rights of traditional peoples? Conservation has a mixed history in this regard (Brockington et al., 2006). In many cases, conservation projects and traditional peoples have supported each other, but there are also many examples where vulnerable peoples have been abused and dispossessed of their ancestral lands. Here we briefly discuss three such examples from different regions of Africa: the “Pygmies” of Central Africa’s forests, the “Bushmen” (also known as San, or First People) of the Kalahari Desert, and the Maasai of East Africa’s savannahs.

    Relocating local people from protected areas, either before or after establishment, is a relatively common strategy across the world. Amongst other reasons, these relocations are thought of as a strategy to reduce stress on wildlife from hunting and other forms of resource extraction which, in turn, enables park managers to reach their conservation and tourism goals quicker. However, in many cases relocated people are not adequately supported as they transitioned to new lifestyles, leading to increased poverty, declining health, and loss of identity. When vulnerable traditional peoples are relocated, humanity also loses a rich cultural heritage, including local knowledge about native wildlife and traditional medicines.

    The Baka, a “Pygmy” tribe that lives in southern Cameroon, have greatly suffered from poorly executed conservation activities. This traditional hunter-gatherer community often identify themselves as “forest peoples” for their strong ties to the forests of Central Africa, which defines their history, culture, and livelihoods. Their ties are now under strain; over the past few decades, several hunting concessions and protected areas were established on ancestral Baka land without proper consultation. In addition to losing their ancestral land, there have also been multiple instances where law enforcement patrols arrested, abused, tortured, and even killed Baka community members that were suspected of illegal hunting (FPP, 2016). Regardless of the back story, it is inherently unjust for hunting to be legal for rich foreigners on ancestral lands where traditional peoples are now prohibited from doing so. This is all even truer when the people who forgo their traditional activities in the name of conservation do not receive compensation for their losses in return.

    The second example involves the “Bushmen” (also known as San, or First People). For tens of thousands of years, the Bushmen have lived a nomadic or semi-nomadic hunting and gathering lifestyle in the Kalahari Desert of Southern Africa. Over the last few centuries however, the Bushmen have struggled to maintain their lifestyles as larger African tribes, and later European colonists have staked claims on their land. In 1961, the government of Botswana established the Central Kalahari Game Reserve to protect wildlife and dedicate a place for the Bushmen to practice their traditional lifestyles. However, the government also drilled wells, and established a school and health post which unintentionally encouraged the Bushmen to adopt a more sedentary lifestyle in which they grew crops and raised livestock in the reserve. In 1985, the government of Botswana decided that the Bushmen’s lifestyles were no longer compatible with the goals of the reserve. After a process that most observers, including the UN (Anaya, 2010), considered inadequate and unethical, between 1997 and 2001 the Bushmen were banned from hunting within the reserve, and forced to relocate to settlements outside its boundaries.

    In 2006, the High Court of Botswana ruled that the relocations were illegal, and that the government had to allow the Bushmen to return to the reserve. The government, however, allowed only a very limited number of people to return, prohibited traditional hunting, and took other actions that failed to meet their human rights obligations (Shaheed, 2016). The government defended these actions by saying that they were protecting biodiversity, and that the hunting pressure by Bushmen amounted to poaching of protected wildlife. To outside observers, it seemed that keeping them away from a lucrative diamond mine, established in the reserve in 2014, was the stronger motivation (Haines, 2016).

    The Maasai are also very familiar with land conflict in the name of conservation. They occupy an area of 160,000 km2 of seasonal lands in the Great Rift Valley in southern Kenya and northern Tanzania. Here they live a semi-nomadic, pastoralist lifestyle, and rely almost entirely on livestock for food and income. In the early 1900s, British colonists began taking lands away from the Maasai to create ranches and later also protected areas. This included the iconic Maasai Mara National Reserve and Serengeti National Park on either side of the Kenya-Tanzania border. Together these parks protect one of the last great mammal migrations in the world, attracting tourists from far and wide.

    Maasai pastoralists who live adjacent to these and other protected areas regularly come in conflict with wildlife, particularly lions, which pose a threat to the herders and their livestock. The Maasai have a tradition of hunting lions, particularly after livestock predation, but also as a traditional rite of passage to manhood. Killing lions is now illegal in Kenya as the region’s lion population is dwindling from the impacts of habitat loss and too many lion hunters. As an alternative to retaliatory killings, the Kenyan government financially compensates herders for predation losses; however, the government has not always been consistent in this compensation (Goldman et al., 2010). At times, corrupt officials have also exploited the Maasai by taking or misusing their share of tourism revenues (although corruption seems to be declining and compensation and revenue sharing have improved in recent years). Also, in Tanzania, tens of thousands of Maasai were evicted from their ancestral land in the Serengeti wildlife corridor in 2013. And yet, instead of strict protection, the land in question was earmarked for a foreign-owned hunting concession (Smith, 2014). (The Tanzanian government has since reversed this land grab and fired those behind it.)

    Conservation conflicts with traditional peoples are unnecessary and avoidable. Research—done by conservation biologists—shows that traditional peoples have a relatively minor impact on the environment, especially when compared to that of commercial hunters and exploited migrant labourers who have little incentive to live sustainability (Thibault and Blaney, 2003; Poulsen et al., 2009; Fa et al., 2016). Conservation biologists and traditional peoples thus face similar concerns: habitat loss and fragmentation, human encroachment, commercial hunting and other capitalist ventures, and armed militias. Such is the case even in 2019, in southern Cameroon, where the clearing of the Meyomessala forests for Chinese-owned rubber plantations not only threatens many threatened and iconic species, but also the livelihoods of the local Baka community (Sixtus, 2008). As such, working together will benefit both conservation biologists and traditional peoples.

    Fortunately, there are several models illustrating the compatibility of conservation and traditional lifestyles. One example comes from northern Kenya, where the community-run Northern Rangeland Trust sustainably manages 44,000 km2 of land. Here, core areas are set aside for wildlife, while buffer areas are subjected to a rotational livestock grazing framework. This model benefits both livestock and wildlife by preventing overgrazing, increasing habitat heterogeneity, and maximising overall biodiversity, thereby allowing 480,000 people (from 15 ethnic groups) living in the area to enjoy peace, prosperity, and healthy ecosystems. Livestock and wildlife populations—which show limited competition under the right conditions (Kartzinel et al., 2015)—are also thriving, and at times they may even benefit one another (Odadi et al., 2011). A major accomplishment here is that the population size of Africa’s rarest antelope, the hirola, doubled in only three and a half years. The area now boasts a growing tourism industry, which boosts employment, and provides revenue that is spent on health, education, and other societal needs.

    Some challenges remain, most notably human-wildlife conflict, and overcoming a history of mistrust. Droughts and political instability have also contributed to tensions between conservationists and traditional peoples in some areas. Even so, conservation biologists have an obligation to follow best practices and ensure that human rights are not violated through conservation activities (Borrini-Feyerabend and Hill, 2015). There is also a need to abide by international laws and to recognize the rights of people who want to live a traditional lifestyle; this includes respecting their right to free, prior, and informed consent (FPIC, see UN-REDD, 2013) before mutually-beneficial conservation actions are implemented. With more African countries adopting a western form of land tenure that enables private land ownership, empowering traditional peoples by helping them to obtain legal title (the right to land ownership that is recognized by the government) can also help establish trust and locally managed protected areas where resources are harvested sustainably (Rai and Bawa, 2013). Recent studies have shown that deforestation rates decline on such legally designated traditional lands, particularly in places undergoing rapid land-use changes (Nolte et al., 2013). Gaining trust and working with traditional peoples is not always easy. But only under those circumstances can we have any hope of establishing a sustainable conservation model that will weather the test of the times.

    Communal lands in East Africa that are dedicated to pastoralism provide a good example illustrating the compatibility between traditional peoples and conservation efforts (McGahey et al., 2007). In contrast to modern livestock farming systems that maintain livestock in a restricted area, pastoralism involves regularly herding livestock to new areas in search of fresh pasture and water. Pastoralists sometimes also use fire to enhance land productivity, which, together with intense but short-term grazing, maintains native grassland and savannah ecosystems by preventing encroachment of woody plants (Section 10.2.1). By keeping their grazing lands suitable for livestock, pastoralists also maintain those areas in a state that is suitable for native biodiversity and the natural resources they need for survival. In fact, levels of biodiversity on well-managed pastoral land may rival (Msuha et al., 2012) or even exceed (ILRI, 2006) that of adjacent protected areas where such activities are excluded.

    Biodiversity conservation and human welfare operate hand-in-hand on unprotected lands, but with a fragile balance that requires continued maintenance.

    However, when the rules governing pastoral systems break down due to agricultural developments and fences that impede pastoralist movements, the resultant breakdown of traditional grazing systems lead to overgrazing, negatively impacting people, livestock, and wildlife (Western et al., 2009b; Groom and Western, 2013). These are the kinds of threats facing the hirola (Beatragus hunteri, CR), also known as the Hunter’s antelope, which shares much of its range with Somali pastoralists in north-eastern Kenya. With fire suppression, elephant extirpation, and a breakdown of traditional grazing systems, trees are encroaching on this facultative grazer’s last remaining strongholds; the loss of grasslands is also harm cattle production in the region (Ali et al., 2017). On pastoralist lands, biodiversity conservation and human livelihoods truly operate hand in hand, but with a fragile balance that requires continued maintenance.

    People who live in rural areas and sell natural resources that they extract from healthy ecosystems also play an important role in conservation by engaging in sustainable natural resource management. Consider all the unprotected estuaries and marine areas that support commercial fisheries for a moment. When fisheries are managed in a sustainable way, not only does this benefit the people that depend on these commercially important species, but other native species can also thrive. Such a win-win outcome was illustrated in Cameroon’s mangrove swamps, where the unsustainable harvesting of mangrove trees for smoking fish was mitigated with fuel-efficient stoves. These new stoves reduced both the amount of time and firewood needed for smoking fish, benefiting the mangroves as well as the fishers’ profit margins (Feka et al., 2009). Fuel-efficient stoves form an important role in reducing firewood harvesting pressure in Cameroon and many other African countries.

    People living in urban centres can also contribute to conservation efforts by raising environmental awareness among fellow citizens, participating in activism, lobbying, and fundraising activities, and generating knowledge through citizen science projects (see Box 15.3). They can also help reduce the multiple pressures that their cities exert on the surrounding environment. Among the most exciting recent developments have been the development and installation of green infrastructure, such as urban forests, green roofs, urban wetlands, permeable sidewalks, urban farms, and rain gardens (Figure 14.2). Not only does green infrastructure save money by reducing energy consumption and pollution clean-up costs, it also reduces overall maintenance (Odefey et al., 2012) and improves overall well-being (Demuzere et al., 2014). Consequently, green infrastructure is increasingly being integrated in urban planning across the world, including North America (EPA, 2018), Europe (Natural England, 2009), Asia (e.g. Kennedy et al., 2016), and in South Africa (Culwick et al., 2016).

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    Figure 14.2 Green infrastructure enables people living in urban centres to reduce their pressure on natural ecosystems and live more comfortable lives. (Top) A green wall to provide cooling and air purification in Madrid, Spain. Photograph by Jean-Pierre Dalbéra, https://www.flickr.com/photos/dalbera/4657766022, CC BY 2.0. (Bottom) A constructed wetland in Harbin, China, built to provide flood control, a wildlife refuge, and a nature experience. Photograph by Richard Primack, CC BY 4.0.

    Many urbanites are also eager to work with government agencies and conservation NGOs to make their cities more biodiversity friendly by restoring urban waterways and wetlands (Box 14.2), and replanting abandoned industrial sites and other damaged urban areas with native vegetation that can support pollinators, birds, and other wildlife. Such efforts foster neighbourhood pride, create a sense of community, and provide a sense of satisfaction to people who like to be close to nature. These restored areas, and other urban green spaces, can also serve to highlight the links between human well-being and nature, which may make those city dwellers who remain on the side-lines of conservation more receptive to the more challenging aspects of conservation, such as prescribed fire and invasive species management (Gaertner et al., 2016). Establishing and maintaining areas to protect biodiversity where people live and work, termed reconciliation ecology (Rosenzweig, 2003), will increase in importance as Africa’s urban centres continue to expand over the next decades (Seto et al., 2011).

    Box 14.2 Importance of Protected Areas in Cities: Insights from the City of Cape Town

    Pippin M. L. Anderson

    Department of Environmental and Geographical Science,

    University of Cape Town, South Africa.

    pippin.anderson@uct.ac.za

    With urbanisation rates of 3% per year, Sub-Saharan Africa’s sprawling cities are predicted to increase in area by seven times over coming decades (Anderson et al., 2014). Much of this growth will be associated with weak decentralised governance and limited resources for environmental management. Just under half of all Africans live below the poverty line, and African city-dwellers tend to make greater use of natural resources than citizens of other continents (Anderson et al., 2014). Meanwhile, biodiversity and conservation concerns tend to be eclipsed by, or be independent of, other pressures such as poverty, unemployment, and access to food, water, and housing. Despite the challenges of promoting biodiversity conservation under these conditions, sprawling cities will benefit greatly from conserving some green space within their boundaries.

    The City of Cape Town in South Africa has exceptional biodiversity; the region around the city hosts some 9,000 plant species on just 90,000 km2 of land. But as urban areas spread, natural areas are being developed to meet housing and economic needs. Elsewhere, native ecosystems are being suppressed by agricultural transformation, invasive species, annual floods and coastal erosion are intensifying, and altered fire regimes are hindering natural processes. These alterations to the natural landscape have significant economic consequences due to eroded ecosystem services (O’Farrell et al., 2012) conservatively valued at US $150–450 million per annum (de Wit et al., 2009). Similarly, urbanisation also reduces human well-being through loss of education and recreation opportunities afforded by green spaces (Goodness and Anderson, 2014).

    The Edith Stephens Nature Reserve, a small (0.39 km2) protected area in the City of Cape Town, illustrates the important role of green space in an urban environment (Figure 14.A). Despite the small size and isolated nature of the reserve, the site provides several benefits to the surrounding community. Originally established to protect a wetland that holds the threatened Cape quillwort (Isoetes capensis, EN), the reserve offers nature-watching opportunities to the public via a bird hide overlooking the wetland, and a quiet neutral space for socialising that is not linked to gang or political territories. The reserve also has an environmental education centre that regularly offers children’s workshops and holiday programs, as well as a teacher-training program. Even so, the site faces considerable urban pressures, including heavy foot traffic across the reserve, nutrient run-off from the adjacent agricultural land and urban area, and informal activities, such as brick cleaning on the property’s boundary.

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    Figure 14.A The Edith Stephens Wetland, South Africa, pictured here with Table Mountain in the background, is surrounded by urban settlement, making it an important reserve for the local communities as it provides green space and ecosystem services. The reserve’s success lies in the fact that it is managed in close collaboration with the adjacent communities. Photograph by Pippin Anderson, CC BY 4.0.

    The reserve was included in the Cape Flats Nature project initiated in 2002, which sought to link urban nature conservation with social justice in the city’s most economically marginal areas (Katzschner, 2013). The idea was to establish conservation practices that integrate ecological sustainability with community empowerment and social well-being. Even though the Cape Flats Nature project ended in 2010, the principles of the project live on through ongoing efforts by the reserve’s small staff and local volunteers recruited from adjacent communities and government public works programs. The reserve has developed good relations with its neighbours, and the staff claim that they enjoy lower incidences of crime than many other protected areas in the city. The Edith Stephens Nature Reserve exemplifies the kind of hybrid conservation practice that is required in an urban African setting where social and biodiversity requirements need to be balanced, especially in small areas with significant development pressures.

    The impact of agriculture

    Habitat loss from agricultural expansion is arguably the biggest current challenge to biodiversity conservation in Africa (Balmford et al., 2012; Laurance et al. 2013; Maxwell et al., 2016). At the root of this problem is the need to supply food and other resources to a growing human population. Exacerbating the situation, much of Sub-Saharan Africa’s arable land has already been degraded to such a degree that it cannot sustain viable food production anymore (Drechsel et al., 2001). Most of these losses are not due to natural factors, but to poor land management practices, such as overgrazing, continual ploughing of fields, and heavy use of fertilisers. These practices release nitrogen, carbon, and oxygen into the atmosphere and compromise the soil’s ability to hold water, leading to erosion, soil salinisation, desertification, and even climate change (Vågen et al., 2005). This not only lead to collapsing ecosystem services, but also increased competition for space as even more land must be converted for agriculture, and to accommodate people and their activities. Such land conflicts are only going to become worse with climate change (Zabel et al., 2014).

    In light of the seemingly irreconcilable conflict between agriculture and conservation, some conservation biologists have suggested that the only way in which we can secure a future for biodiversity is through a land sparing approach, in which agricultural investments are focussed on intensifying practices on land already dedicated to farming and no more. One of the main drawbacks of such a high-yield approach is that the impact of intensive agricultural practices degrades natural ecosystems even far from the immediate area, for example through nutrient and pesticide pollution (Section 7.1). For that reason, others support a land sharing approach that promotes biodiversity-friendly agricultural practices, even if that means agricultural lands continue to expand. One of the main drawbacks of this land-sharing approach is that it still alters ecosystem composition, which would threaten species that need large territories and habitats, in addition to leading to more human-wildlife conflict (Section 14.4).

    While the land-sparing versus land-sharing frameworks make for good intellectual debate, the reality is that both are undesirable scenarios when carried out as opposite extremes. There is no denying that agriculture is important—it’s the primary source of livelihood for millions of Africans, and critical for food security. But because there is a finite amount of land available for food production, we have no choice but to develop methods that will allow greater yields on existing agricultural lands without depleting the soil or damaging more ecosystems. In other words, we need to adopt a hybrid approach where some lands are dedicated to large protected areas where human activities are restricted, some lands are dedicated to wildlife-friendly agro-ecosystems, and some lands are used for intensive food production (Fischer et al., 2014; Law et al., 2017). Much of Africa has employed a similar structure historically and even today, where large areas that are relatively untouched or regenerating are interspersed with low-intensity traditional agricultural systems that continue to support a range of native species (Şekercioğlu, 2012). Traditional farming systems offer many strategies showing how natural ecosystem services can be used to improve yields, including the use of biocontrol and crop diversification to keep pests and diseases at bay, and planting of nitrogen-fixing legumes to improve soil fertility. This is in stark contrast to intensive modern agricultural practices dedicated to single crop specialisation; these impoverished ecosystems cannot maintain themselves but rather rely on continuous use of fertilisers and pesticides to remain productive.

    Biodiversity-friendly farming practices can also produce economic benefits; and so, many government programs are now promoting sustainable agricultural intensification.

    With the increased realisation that biodiversity-friendly farming practices can also produce economic benefits, many government programs have begun to promote and subsidise the adoption of sustainable agricultural intensification (http://www.fao.org/ag/ca/AfricaTrainingManual.html; see also Pretty et al., 2011; Garnett et al., 2013). Also known as conservation agriculture, this farming approach blends traditional agricultural practices with improved and locally adapted crops, as well as integrated crop and pest management strategies (Figure 14.3) to boost yields on existing farmland while creating cost and labour savings; it may even reduce the amount of land under cultivation (Stevenson et al., 2013). Some of these strategies include minimal tilling, crop rotation, intercropping, and terracing (to prevent agricultural runoff which, in turn, prevents erosion). Soil nutrient levels are enhanced through fertiliser microdosing, and by planting legumes, encouraging decomposition by termites, and using crop residues as mulch before composting it directly into the soil. Crop yields are further improved by maintaining windbreaks such as riparian buffer zones, which have the added benefit of enhancing the diversity of seed dispersers, biocontrol agents, and pollinators. In one study, fertiliser microdosing increased sorghum and millet yields and, thus, incomes for 25,000 smallholder farmers in Mali, Burkina Faso, and Niger by 50–130% (Tabo et al., 2011). Another region-wide study found that conservation agricultural techniques could increase average crop yields by nearly 400 kg per hectare (Corbeels et al., 2014). It is important to remember that conservation agriculture is a departure from both traditional and intensive monocrop farming techniques. Adequately training farmers in best practices and new techniques is therefore crucial to program success (Gatare et al., 2013).

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    Figure 14.3 A vegetable farm maintained by a local community living adjacent to Gorongosa National Park, Mozambique. The farm is maintained following several conservation agriculture principles. For example, to conserve water, the ground is covered in mulch obtained from a nearby grassy field, while a drip irrigation system was installed by park staff and a local women’s association. To further strengthen local development and collaboration, part of the crop is also sold at the tourist restaurant inside the park. Photograph by Iñaki Abella Gutiérrez/Bio+, CC BY. 4.0.

    To take advantage of the multiple benefits to be gained from integrated, biodiversity-friendly farming techniques, entire industries have started adopting such practices. Among the most prominent are cacao and coffee, where many growers now produce their crops under native shade trees (Box 14.3). While Africa has had a long history of shade-grown cacao and coffee production, recent decades have seen many farmers transitioning towards intensive farming in full sun, which allows for easier mechanisation. But crops grown in full sun are generally also of lower quality and more susceptible to pest outbreaks (Kellerman et al., 2008; Bisseleua et al., 2009; Tscharntke et al., 2011). In contrast, shade-grown cacao and coffee benefits both the farmers and biodiversity: a study from Ethiopia found that shade coffee farms had over double the number of bird species in comparison with nearby forest sites (Buechley et al., 2015). Shade farming could also be a strategy for farmers trying to cope with increasing temperatures due to climate change (Blaser et al., 2018). Considering the large global markets for cacao and coffee, reverting to traditional growing methods here would have a large positive impact on the environment simply due to the economy of scale.

    Box 14.3 Preserving Biodiversity Through Shaded Agroforestry

    Hervé D. Bisseleua

    World Agroforestry Centre (ICRAF),

    Nairobi, Kenya.

    hbissel@gmail.com

    Chocolate is one of the most universal treats in the world, but could your sweet tooth be increasing biodiversity loss? The chocolate tree (Theobroma cacao) is traditionally grown in areas with dense and diverse canopies of shade trees, home to an abundant variety of plants and animals (Figure 14.B). The chocolate industry is strongly dependent on small-scale agriculture, but also highly vulnerable to pest and disease outbreaks, and climate change. These production challenges combined with increasing global demand for chocolate has increased economic and social pressures to achieve higher yields within a shorter timeframe. Higher yields could be achieved through reduced shade tree management and increased use of chemical pesticides and fertiliser. But these techniques lead to deforestation, biodiversity loss, and loss of ecosystem functioning. Higher yield techniques in the short term are also not sustainable over the long term: work in Cameroon and elsewhere showed that the promotion of high-yielding hybrid cacao varieties under direct full sun have contributed to more frequent outbreaks of pests and diseases (Kellerman et al., 2008; Bisseleua et al., 2009; Tscharntke et al., 2011).

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    Figure 14.B (Top) Cacao grown as a monoculture, without shade trees, in Ghana. Biodiversity is greatly reduced and the cacao trees are more susceptible to pests and diseases in this framework. Photograph by Phillip Allman, CC BY 4.0. (Bottom) Coffee grown under a diverse canopy of trees in Ethiopia. Like cacao, coffee cultivated under shade provides a forest structure in which birds, insects, and other wildlife can flourish. Photograph by Evan Buechley, CC BY 4.0.

    To achieve more sustainable cacao production, and to benefit from ecosystem services, such as enhanced biological control of pests and diseases, and increased soil fertility, West Africa’s cacao farmers are now gradually returning to agroforestry practices that embrace increased shade tree diversity. Farmers adopting these techniques are already reaping benefits. For instance, in Ghana and Cameroon, cacao yields from shaded cacao agroforestry systems are 12–23% higher compared to full sun systems (Bisseleua et al., 2009; Asare and Raebild, 2016). In eastern Côte d’Ivoire, the use of leguminous trees as shade in rehabilitated cacao plantations is also reported to increase the survival rate and yield of cacao trees (Smith Dumont et al., 2014). Cacao grown in shade may produce for 60–100 years, whereas production may only last for 20 years without shade (Obiri et al., 2007). In addition to environmental services, diversified shade trees may also provide additional income opportunities, such as timber and firewood production, medicine, local spices, and fruit, from native shade trees such as the njangsang tree (Ricinodendron heudelotii) and bush mango (Irvingia gabonensis) (Smith Dumont et al., 2014). Importantly, in all these multi-strata systems, a higher density and diversity of shade trees means higher densities and diversity of pollinators and biological pest control agents such as ants and social wasps, which in turn increase cacao yields even more (Bisseleua et al., 2017).

    In conclusion, better land management practices, such as allowing a diversity of shade trees to grow among the cacao crop, increases both biodiversity and revenue for farmers. Tropical agroforestry is thus a promising approach to reconcile biodiversity conservation and economic development. Educating farmers on shaded agroforestry systems and creating complimentary economic incentives and policies would help farmers adapt to better management practices faster, ultimately allowing agroforestry systems to contribute more to biodiversity conservation. A guilt-free sweet tooth, indeed!

    Sustainable agricultural practices are much needed in the conservation portfolio of Africa, where farmers have been slow to adopt conservation agriculture. Two main challenges are noted. First, spreading ideas and innovations across different agricultural sectors has been challenging, and much work remains to implement them. Second, due to incredible ecosystem diversity across the region, specific practices are not equally suitable everywhere; there is thus need for more research into flexible practices that can be modified to meet local growing conditions (Giller et al., 2009). Strengthening coordination of agricultural research and cooperation at local and regional scales (Gonthier et al., 2014), as well as better land-use allocation (Law et al., 2015) may solve some food production challenges. Adapting biodiversity-friendly certification schemes to consider local dynamics might also encourage more African farmers to adopt biodiversity-friendly techniques (Gove et al. 2008; Buechley et al., 2015). Not only would biodiversity benefit, but these practices would enable farmers across Africa to receive higher prices for their crops and recover a large portion of the land lost to land degradation each year without the need for more land conversion.

    The impact of logging, mining, and other extractive industries

    Conservationists are also dependent on extractive industries. Rather than criticise, it is more productive to partner with and influence these industries to contribute to conservation efforts.

    As with intensive agriculture, high-impact resource extraction industries have not traditionally been compatible with conservation needs. These include mining, oil and gas extraction, dredging, quarrying, and logging, which have often been associated with complete ecosystem destruction. While it is easy to criticise these industries for their impact on nature, it is important for conservationists to remember that we are all dependent on those industries in some way or other, even to perform our conservation activities. Rather than criticise, it is more productive to partner with and influence with industries to contribute to conservation efforts.

    There are many examples illustrating how partnerships between conservation biologists and extractive industries can benefit conservation. One of the best examples comes from the timber industry, which has the potential to greatly increase forest conservation opportunities (Clark et al., 2009). Traditionally known for leaving unsightly clear-cuts behind them, research has shown that improved logging techniques facilitate quicker ecosystem recovery after harvesting, which in turn also benefits biodiversity. For example, while the response of wildlife to logging differs depending on the harvesting method and forest type (Ofori-Boateng et al., 2013), primates (Stokes et al., 2010; Morgan et al., 2018), amphibians (Ofori-Boateng et al. 2013), and birds (Şekercioğlu, 2002) can all tolerate responsible-done light-touch logging techniques (but see also Bicknell et al., 2013; Gatti et al., 2015).

    Guided by this research, some sectors of the timber industry have been keen to adopt more sustainable logging techniques (Figure 14.4) that focus on reducing damage to the soil, stream banks, and remaining trees, while removing just the largest trees. This approach reduces soil disturbance, erosion, waste, and carbon emissions. The Forest Stewardship Council (FSC) and other similar organizations are setting certification standards for sustainable logging, which enable certified logging operations to sell their products at higher prices on world markets. In addition to impact reduction within logged areas, certification schemes typically also require timber companies to avoid logging high conservation value forests, which is a good strategy for protecting ecosystem services and biodiversity in general. Some agroforestry companies also allow local people to cultivate rare medicinal and aromatic plants in the shaded areas on their concessions which reduces harvesting pressure on wild populations (Rao et al., 2004). Lastly, a key element for wildlife management in logged forests is to stop hunters, fishers, trappers, and plant collectors from entering the impacted area after timber harvest by closing unused logging roads. (For more discussion on the impact of the logging road on biodiversity, see Laurance et al., 2014 and Benítez-López et al., 2017.) (For an example in fisheries, see Box 7.2)

    Fig_14.4_Wilson-2.jpg
    Figure 14.4 Reduced impact logging techniques facilitate quicker ecosystem recovery. In this example from Mozambique, foresters took only the largest trees, and left some scattered logging slash (i.e. cut branches) to provide shelter for wildlife and to promote natural seed germination. Logged areas are also surrounded by stands of intact forest to promote wildlife and seed dispersal. Photograph by Johnny Wilson, CC BY 4.0.

    Many African mining companies have also become active partners in conservation. These partnerships include contributions like providing funding for conservation activities, participating in biodiversity offset programs (Section 10.3.3), and subsidising conservation agriculture efforts. South Africa offers several examples illustrating how extractive industries can develop productive conservation partnerships. Two South African diamond trading companies, De Beers Group and E. Oppenheimer and Son, converted 2,500 km2 of their properties earmarked for diamond mining and exploration into protected areas used for ecotourism and environmental research. Also, in South Africa, the petrochemical company SASOL supports a wide range of environmental programs, including sponsoring natural history field guides, anti-poaching programs, and threatened species recovery projects.

    Despite these and other examples of progress, many challenges associated with extractive industries remain unsolved. For example, pollution from these industries continues to threaten Africa’s environment, and many extractive companies remain unfriendly towards conservation activities. Many of these challenges stem from efforts to cut costs by ignoring legal and regulatory requirements, particularly when it involves stakeholders from outside Africa who prioritise short-term profits over long-term sustainability. Tardy monitoring and enforcement of regulatory requirements (sometimes driven by corruption) also remain as obstacles (Linder and Palkovitz, 2016). The best solutions for overcoming these challenges involve continued diplomacy to establish new (and strengthen existing) partnerships with such industries. Conservation biologists also need to educate industry workers and the general public to be on the lookout for environmental violations and inadequate law enforcement, which needs to be reported and addressed before more damage is done. Above all, it is important to remind legislators and other members of society that environmental damage can harm, sometimes irreversibly, our own ability to have fulfilling lives.


    This page titled 14.1: Human-Dominated Landscapes is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by John W. Wilson & Richard B. Primack (Open Book Publishers) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.