Explaining the emergence of land-use frontiers.

Land-use expansion is linked to major sustainability concerns including climate change, food security and biodiversity loss. This expansion is largely concentrated in so-called 'frontiers', defined here as places experiencing marked transformations owing to rapid resource exploitation. Understanding the mechanisms shaping these frontiers is crucial for sustainability. Previous work focused mainly on explaining how active frontiers advance, in particular, into tropical forests. Comparatively, our understanding of how frontiers emerge in territories considered marginal in terms of agricultural productivity and global market integration remains weak. We synthesize conceptual tools explaining resource and land-use frontiers, including theories of land rent and agglomeration economies, of frontiers as successive waves, spaces of territorialization, friction and opportunities, anticipation and expectation. We then propose a new theory of frontier emergence, which identifies exogenous pushes, legacies of past waves and actors' anticipations as key mechanisms by which frontiers emerge. Processes of differential rent creation and capture and the built-up of agglomeration economies then constitute key mechanisms sustaining active frontiers. Finally, we discuss five implications for the governance of frontiers for sustainability. Our theory focuses on agriculture and deforestation frontiers in the tropics but can be inspirational for other frontier processes including for extractive resources, such as minerals.

Balancing the trade-offs between land productivity, labor productivity and labor intensity.

Agricultural intensification, through increased yields, and raising incomes, through enhanced labor productivity, are two dimensions prioritized for sustainable agricultural development. Prioritizing these two outcomes leaves labor intensity as a hidden adjustment variable. Yet, when agriculture is mainstay and the prospects of labor absorption in other sectors are scarce, the density of agricultural employment is central for livelihoods. We revise relationships of land and labor productivity and labor intensity with farm size, using standardized data for 32 developing countries. We show that labor productivity increases with farm size, while land productivity and labor intensity decrease with farm size nonlinearly. Technical efficiency increases with farm size. We further systematize the evidence on how, beyond the farm level, local contexts can be pivotal in choosing how to prioritize the dimensions of the trade-off space. Our findings contribute to debates on the fate of small-scale farmers, and call for contextualized decisions.

Resource frontiers and agglomeration economies: The varied logics of transnational land-based investing in Southern and Eastern Africa.

Actor-level data on large-scale commercial agriculture in Sub-Saharan Africa are scarce. The peculiar choice of transnational investing in African land has, therefore, been subject to conjecture. Addressing this gap, we reconstructed the underlying logics of investment location choices in a Bayesian network, using firm- and actor-level interview and spatial data from 37 transnational agriculture and forestry investments across 121 sites in Mozambique, Zambia, Tanzania, and Ethiopia. We distinguish four investment locations across gradients of resource frontiers and agglomeration economies to derive the preferred locations of different investors with varied skillsets and market reach (i.e., track record). In contrast to newcomers, investors with extensive track records are more likely to expand the land use frontier, but they are also likely to survive the high transaction costs of the pre-commercial frontier. We highlight key comparative advantages of Southern and Eastern African frontiers and map the most probable categories of investment locations.