Farmer Tree Planting Barriers to Sustainable Forest Management - Smallholder Tree Growing for Rural Development and Environmental Services - page 423

environmental services is essential, yet, entails a rather complex process. The
outcome for tree-based systems may differ considerably, and even contradict
expectations (Van Weerd and Snelder, Chapter 16, this volume), discouraging
potential stakeholders to participate in the PES field. Given ongoing land-use
changes and increasing population pressure on a wide array of forest- and agro-
ecosystems, broader knowledge of alternative agroforestry practices and associ-
ated services is essential and to be communicated among both farmers and
scientists alike. Information is lacking on practices that offer multiple opportu-
nities for farmers to improve farm production and incomes, and also provide
productive and protective forests functions like those discusses by Sharma et al.
(this volume).
Another concern is that, in the absence of a comprehensible 'reward structure',
the presence or absence of environmental services is left to decision makers to
whom off-farm benefits and costs are 'externalities'. Development of efficient and
effective reward structures for environmental services, is thus an important way to
achieve environment plus development goals (Tomich et al. 1998, 2001; Landell-
Mills and Porras 2002; Murdiyarso et al. 2002).
In current discussions on terrestrial carbon storage in the context of the Kyoto
protocol and similar efforts to slow down the increase in atmospheric CO 2 concen-
trations, the focus has been on reforestation with specific efforts for lands not
'forested' in 1990. For mechanisms such as these it is an important issue whether
or not 'agroforestry' can qualify under the formal definitions - even though existing
data show a considerable potential for increasing the 'time averaged carbon stock'
of land managed by farmers, through an array of agroforestry practices (Van
Noordwijk et al. 1998a, b; Palm et al. 1999; Roshetko et al. 2002; Hairiah et al.
2002; Tomich et al. 2002; Van Noordwijk et al. 2003). Apart from the lack of rec-
ognition, however, current mechanisms will provide such an administrative burden
that it is likely that 'transaction costs' will form most (if not all) of what buyers of
certified carbon credits pay, with little (if anything) ending up in farmers' pockets.
However, enabling the establishment of viable, market-oriented smallholder tree
farming systems would justify 'carbon investment' and satisfy sustainable develop-
ment criteria (Roshetko et al. 2007).
The relation between trees and water continues to be subject to confusion in
the public debate (though not addressed much within this topic). The fact that
young tree plantations, especially of evergreen species tend to use more water
than established, deciduous forests or agricultural (non-irrigated) lands has
gained attention in the form of the Eucalyptus debate. While there is no reason
to single out Eucalyptus species in this regard, the high water use of fast grow-
ing, evergreen trees can be a concern in areas with a shortage of groundwater
or subsurface flows of water. In other areas such interception of subsurface
flows can be seen as the basis of an 'environmental service function', where it
prevents salt movement in groundwater flows. 'Environmental service' percep-
tions will thus depend on the local agro-ecosystem, and should be left to local
governance structures to decide.