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the demand and the land generating product (Lambin et al., 2003). Meta-analyses
indicate the power of different combinations of factors to account for land changes,
by time and place, including institutions, economy and culture (Agarwal and
Yadama, 1997; Barbier and Burgess, 2001; Lambin et al., 2001). This variance has
led to such general conclusions as deforestation occurs whenever and wherever the
demand for forest use and the power to achieve it exist (paraphrasing Angelsen and
Kaimowitz, 1999), especially where 'frontier' forest lands exist (Barbier, 2004).
Place-based research points to the role of the specifi c factors that generate this
demand-power function, such as markets (Brown and Pearce, 1994), policy
(Binswanger, 1991), transportation-road networks (Cropper et al., 1999) and
household lifecycles (Perez and Walker, 2002) impact on deforestation. Yet other
research explores older theoretical themes in new ways, such as induced intensifi ca-
tion (Laney, 2004), as well as the role of different explanatory approaches for
addressing land change (Roy Chowdhury and Turner, 2006).
Land use to land cover and environment
Sustained documentation of the consequences of land uses on land covers continues,
although more attention has been given to environmental drawdown than to sus-
tainable activities (e.g., Barrows, 1991; Kasperson et al., 1995; Nepstad et al., 1999;
Seto et al., 2000; MEA, 2005; but see Ellis and Wang, 1997; Johnson and Lewis,
2007). Immediate and visible ecological consequences, such as soil erosion, have
increasingly shared attention with less visible ecological and earth system ones,
including landscape functioning under different levels of habitat loss and fragmenta-
tion (Skole and Tucker, 1993; Sala et al., 2000; Higgins et al., 2003; DeFries et al.,
2004). Land changes often open the door for invasive species which not only change
plant functional relationships but the capacity of the ecosystem to restore itself for
some future use, as in swidden or slash-and-burn cultivation, or the economic costs
of combating the invasion (Mooney and Hobbs, 2000; Schneider and Geoghegan,
2006). Such 'on-site' consequences are increasingly matched and in regard to the
functioning of the earth system, superseded by those cumulative consequences of
repeated land uses worldwide (Meyer and Turner, 1994).
Perhaps the best documented global-scale impacts are those of tropical deforesta-
tion, largely for cultivation and pasture, on the loss of biodiversity (e.g., Cervigni,
2001; DIVERSITAS, 2002) and on global climate warming, through carbon and
radiative dynamics (e.g., Houghton et al., 2000; Zhang et al., 2001; Pielke, 2002;
Steffen et al., 2003). Importantly, land-change research has also demonstrated that
regional-scale land changes have signifi cant consequences on regional temperature
and precipitation regimes (e.g., Pielke et al., 1999), in some cases exceeding the
projected changes of global climate. In addition, recent but debated research sug-
gests that urban conglomerations may be affecting warming at regional scales and
above (Kalnay and Cai, 2003; Zhou et al., 2004).
Environment to land cover and land use
Research on land-cover change feedbacks on land uses has grown from such base
agronomic and climate change issues as, respectively, soil erosion and crop responses
(Rosenzweig and Parry, 1994; Lal, 2004) to questions of ecosystem services for land
