FUNCTIONAL VALUE OF BIODIVERSITY PROJECT
(A BNPP ‘Forest And Biodiversity’ Window Project)
IN BRIEF: Objectives, Approach, Impacts
11 July 2002
Objective: provide a sound basis for identifying and designing policies and projects
that use forest conservation as a tool for maintaining the level, quality, and
regularity of water flows.
Efforts to ‘mainstream’ biodiversity have been frustrated by lack of scientifically based,
comprehensive assessments of the functional contribution of biodiversity conservation
to rural livelihoods and economic development. While there are many such functional
contributions, one of the most frequently discussed is the contribution of conservation
to maintenance of key hydrological processes. It is supposed – plausibly but without
much evidence – that changes in upland land use practices could help poor hilldwellers, conserve biodiversity, and provide ‘bankable’ benefits for downslope urbandwellers. Yet lack of rigor or depth in these discussions could lead both to overlooked
opportunities and to unrealistic expectations. For instance, it is possible that in some
water basins peri-urban wetlands are both more threatened and more critical to urban
flood prevention than upland forests.
This project will assist the Bank and its clients in project development and policy
analysis by:
 providing systematic assessments, for significant areas of the humid tropics, of the
hydrological value of forests with biodiversity significance in promoting local
livelihoods and resilience to economic and environmental shocks.
 assessing the nature, magnitude, geographical scope, and relation to biodiversity and
poverty of these hydrological values and processes
 forging a strategic partnerships between the ASB (Alternatives to Slash and Burn)
Consortium of CGIAR-affiliated research organizations and their local partners
(with expertise in agronomy, forestry, biology, and local-scale hydrological
processes), with the scientific research community (with expertise in large-scale
hydrological processes) and with the World Bank ( with expertise in poverty,
economic geography, and environmental services)
 developing and applying analytic tools to the operational and policy concerns.
Tasks and framework
The project will look across potential hydrological impacts of forest loss such as:
flooding, changes in dry season flow, changes in total water yield, sedimentation, and
an landslide risk. It will look across different scales: continental, water basin, small
watershed, microwatershed. It will try to answer the following questions:

which kinds of hydrological impacts can be expected at different scales? For
instance, it will assess the propositions that large-scale deforestation has no
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impact on flooding or sedimentation at the level of large water basins. This
proposition is widely believed by hydrologists and widely disbelieved by just
about everyone else. But quantitative assessments are lacking.

what downstream and downslope areas are vulnerable to hydrological impacts
of forest modification? -- and what are their characteristics? How many people
are vulnerable? Are the most vulnerable also the poorest?

Where are the critical ‘hydrological hotspot’ areas where land cover change
might cause such vulnerability? What are the biodiversity characteristics of
these areas? How many people live in these areas? How poor are they? (for
areas where poverty data is available)

What are the policy implications of these relationships? Under what
geophysical, social, and economic conditions does it make sense to intervene,
and what kinds of interventions are available? Where data permit: are
vulnerable populations richer than ‘hydrological hotspot’ populations? (in
which case environmental services markets might be advisable) – or vice versa
(in which case such markets would have perverse distributional consequences).
The project attacks these questions by assembling spatial data on land cover,
topography poverty, and biodiversity, applying models of hydrological flows, and
assessing results based on an understanding of underlying agronomic, economic, and
biophysical processes. Study areas include:

the global humid tropics, at coarse resolution

Central America and Montane Mainland Southeast Asia at higher resolution

the Mae Chaem watershed (Thailand) and a Central American watershed
(tentatively designated as the Rio Paz of El Salvador) at fine resolution
Current and intended project impacts
Links to forest policy dialogue and operational projects
The greatest hoped-for impact of the project is in shaping the agenda related to
developing environmental services markets and other approaches to mainstream
biodiversity based on palpable impacts on water quality, quantity, and regularity. The
‘environmental services of forests’ agenda is prominent in the Bank’s Environmental
Strategy, its revised Forest Policy and in the new PROFOR (Programme for Forests)
partnership to be hosted by the Bank. It is an active topic of interest in the LAC region,
where environmental service systems projects have been implemented and are under
discussion. Other regions (ECA, EAS, SAR and AFR) have also expressed interest and
discussions are underway to assist them in introducing the concept at an operational
level.
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Millennium Ecosystem Assessment
The project is an important contribution to the ASB cross-cutting assessment of ‘Forest
and Agroecosystems Tradeoffs in the Tropics’ that has been selected as a sub-global
component of the Millennium Ecosystem Assessment (MA). The datasets and
knowledge generated by the BNPP project will also be of direct relevance to the lead
authors of several chapters of the three global-scale assessment reports; Trends and
Conditions, Scenarios, and Response Options. The project is of particular relevance to
the MA since it too is designed to identify opportunities for joint improvement in the
provision of (multiple) ecosystem services and in human well-being
World Development Report 2003
The project’s initial phase contributed to some of the Report’s most important analytic
and graphical characterization of population links to fragile lands and to forests, a
foundation of the spatial framework that guided the report.
Contributions to poverty assessments
The project may contribute to poverty and vulnerability assessments by linking newly
available spatial maps of poverty (developed in DEC) to other kinds of geographical
information.
Helping build datasets of global interest and applicability
High resolution urban area and administrative division data have already been used as
input for the next improved version of the Gridded Population of the World (GPW 3)
dataset by CIESIN, a standard reference dataset used for many purposes. The project
expects to produce and disseminate a much wider array of applicable data.
Building bridges between the policy and scientific communities
The project is linking geophysical researchers on hydrology, with powerful scientific
tools but weak links to policy, with policy-oriented social scientists.
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