Valuing ecosystem services for integrated landscape management in Zimbabwe

Valuing ecosystem services –– the benefits humans obtain from earth’s many life-support systems –– is an important step in devising interventions to achieve sustainable livelihoods and climate resilience.

Zimbabwe is highly dependent on land and natural resources for livelihoods and economic growth, but the country is experiencing high levels of land degradation which threatens this resource base on which most of the nation’s population depends. We saw the devastating impact of land degradation in several districts of the country, where deforestation, overgrazing, unsustainable agriculture, and mining result in soil erosion, reduced agricultural productivity, loss of biodiversity, contamination of water sources, and disruption of local ecosystems. Land degradation costs $112 per person each year in Zimbabwe, totaling $1.8 billion. This excludes the indirect impacts of poor soils such as reduced water supply and declining crop yields. All of these effects are increasing poverty and food insecurity.

To help address these problems, the World Bank is supporting Zimbabwe to improve and sustainably manage the ecosystem services provided by the country’s critical landscapes . A technical assistance effort entailed a Whole-of-Government collaboration between the country’s Environment Directorate of the Ministry of Environment, Climate, Tourism and Hospitality Industry and counterparts in the Ministry of Lands, Agriculture, Water, Fisheries and Rural Development. Through a process that combined modeling approaches for ecosystem services and consultations with stakeholders in the public and private sectors, civil society, and farmer groups, an evidence base for sustainable landscape management investments in the country was generated. A national screening assessment was undertaken to identify areas in Zimbabwe that are providing a high level of key ecosystem services benefitting communities, as well as areas experiencing or at risk of significant land degradation.

Through the assessment and research, we have identified three major policies to address land degradation and enhance ecosystem services in Zimbabwe which will assist the country in addressing poverty and food insecurity:

1. Scaling up climate-smart agriculture with emphasis put towards on-farm and productive landscape solutions, food value chain and livelihood solutions, and public policy and incentive solutions.

2. Investing in sustainable forest management to maintain the health and integrity of forest ecosystems, conserve biodiversity, mitigate climate change, and provide livelihoods for communities that depend on forests.

3. Leveraging climate finance and piloting payments for ecosystem services to incentivize sustainable landscape management and climate action. The private sector can play a major role for this through financing projects that contribute to sustainable landscape management and directing financial flows away from projects with negative impacts on biodiversity and ecosystem services.  Environmental fiscal policy reforms that value natural capital can provide incentives for the private sector to co-invest in the sustainable use of land and natural resources and contribute toward net domestic resource mobilization in Zimbabwe.

The national screening identified several important landscapes for more detailed assessment, including the Mazowe Catchment, which spans 40,000 km2 north of Harare. This catchment was estimated to provide a high level of ecosystem services making it a promising prospect for conserving and enhancing services provision.

Our detailed ecosystem assessment indicates that productive natural ecosystems in the Mazowe Catchment are being lost and degraded by poorly planned and managed commercial and small-scale livelihood activities. Such things as cropland expansion, fuelwood harvesting, and illegal mining associated with poverty, population growth, and lack of secure property rights are the major drivers of land degradation. Cropland expansion, the main strategy used by farmers for increasing food production, land scarcity, and poor land management practices lead to high soil erosion rates, particularly in communal areas, contributing to water quality and sedimentation problems.

Population pressure has increased the harvesting of firewood and worsened pressure on the remaining grazing lands. Climate change has contributed to significant reductions in crop yields due to greater heat stress and more erratic rainfall patterns in addition to reducing groundwater recharge and surface runoff in the Catchment.

Ecosystem services supplied by natural, unmanaged ecosystems are more valuable than the agricultural production value of cultivated areas ($576 per ha for natural ecosystems versus $231 per ha for agricultural land). Furthermore, agricultural systems depend strongly on many ecosystem services provided by natural ecosystems such as genetic resources used in crop and livestock breeding, soil fertility, nutrient cycling, crop pollination, water provision, and pest and disease control.

Within the Mazowe Catchment, cultivated areas contribute a gross margin value of $68 million per year, while the remaining natural areas support a range of provisioning, regulating, and cultural ecosystem services, providing a benefit of $429 million per year.  Ecosystem inputs to livestock production are estimated at $65 million per year. The Catchment has relatively high populations of cattle, due to its large rural population and the socioeconomic importance of cattle for rural households. Wild resource harvesting of wood, thatching grass, wild plant foods, mushrooms, and honey is estimated to be worth at least $106 million per year.

Rural tourism attractions in the Mazowe Catchment were estimated to generate about $43 million or 4.6% of national tourism. This is a significant source of revenue generation, employment, and improvement in the quality of life for residents. Most of this value ($36 million) is derived from natural ecosystem areas, including the Umfurudzi Safari Area, part of Nyanga National Park, and popular hiking spots such as Domboshawa, and underscores the importance of nature-based economic development in Zimbabwe.

Vegetation cover mediates the infiltration of rainfall into the ground and helps to recharge groundwater for domestic, agricultural, and industrial uses. Vegetation cover also supports water supply by reducing erosion and trapping sediments. Maintaining natural vegetation cover in the Catchment thus saves about $250 million per year in water supply costs through groundwater recharge ($84 million) and sediment retention ($166 million).

While much of the Mazowe Catchment has low biomass due to historical conversion of natural vegetation to agriculture, settlement, mining and other uses, there are some notable areas of relatively dense woody natural habitats remaining which do store significant quantities of carbon. Maintaining such vegetation cover helps to retain carbon in the ecosystems and avoids its emissions into the atmosphere. Such retention of carbon in the ecosystem, valued in terms of the avoided costs of climate change, amounts to $1.23 billion per year, in addition to offering a potential source income for Zimbabwe through international carbon markets.

Sustainable landscape management practices that entail approaches that help to ensure the long-term productivity, ecological health, and resilience of land resources while minimizing negative environmental and social impacts are needed to sustain livelihoods and economy of Mazowe Catchment. Currently, the benefits from the Catchment are being undermined by land degradation, often for short-term gains such as expansion of low-yielding agriculture.  Public investment to scale up sustainable landscape management in the Catchment is cost-effective with every $100 invested in landscape interventions generating $170 benefits. Promoting policies and investing in natural resource management will help preserve ecosystem services and build resilience.

This technical assistance effort was funded through ProGreen, A Global Partnership for Sustainable and Resilient Landscapes, a trust fund administered by the World Bank, with funding from the German and Swedish governments.