Table 2. Central trends and challenges in land-use frontiers.

Central trends and challenges in land-use frontiers
Economic globalization The relaxing of international trade barriers and subsequent globalization of supply chains is an underlying driver of land-use challenges worldwide and in land-use frontiers (Lawrence et al. 2019). Economic globalization also increases the influence of large-scale agribusiness enterprises and international financial flows on land-use decisions. This may in some cases lead to a weakening of national policies intended to promote land governance supporting smallholder farmers (Lambin and Meyfroidt 2011). These economic-driven challenges affect global supply chains and demand land-based resources, resulting in changes in international prices, as well as transnational flows of commodities, capital, and labor (Hertel et al. 2019).
Challenges driven by economic globalization Explanation and corresponding literature
(A) Commodity crop expansion and intensification of commercial plantations Expansion of large-scale, export-oriented, intensive crop production has dramatically transformed rural landscapes and communities in low-income countries (Meyfroidt et al. 2010). Commodity crop expansion into forests or available cropland also affects local communities as they use this land for logging, grazing, or fallow among other uses (Haberl et al. 2007, Ramankutty et al. 2008). Commercial or large-scale plantations of palm trees or timber in frontier regions involve different socio-spatial challenges (Garrett et al. 2018). For example, the overcapacity of wood-based industries requires large amounts of timber, which encourages forest clearing (Curran et al. 2004).
(B) Transnational land deals or transnational land acquisitions Transnational land deals or large-scale land deals specifically refer to the acquisition of land or land-based investments, i.e., deals, primarily targeting low-income countries in Africa, Latin America, and Eastern Europe. This term is usually restricted to deals in low- and middle-income countries only and excludes deals where only domestic actors are involved (Anseeuw et al. 2011). The land uses that are envisioned in these deals are agriculture, forestry, and speculation.
Looming scarcity of productive land Looming land scarcity increases the complexity of future pathways of land-use change globally (Lambin and Meyfroidt 2011). Land resource scarcities will likely continue to be a constraint in the quest for achieving food security in land-use frontiers (cf. Alexandratos and Bruinsma 2012).
Challenges driven by looming scarcity of productive land Explanation and corresponding literature
(B) Land scarcity The acceleration of economic globalization in tandem with a looming scarcity of productive land globally (Lambin et al. 2013) may render land governance strategies or public and private land-use policies less effective in promoting land uses that enhance food production while preserving ecosystems (Meyfroidt et al. 2013). Productive land suitable for cropping is a globally finite and scarce natural resource, to which commodity crop expansion contributes (Ridoutt and Navarro Garcia 2020).
(B) Land competition or land rush Investors are competing for land with smallholder farmers and local farming communities (Anseeuw et al. 2011). Low-income countries supply important commodities, biodiversity, and carbon sinks to the rest of the world. In this context, land-use frontiers emerge as satisfying demands from distant countries for agricultural goods and mining products (Andriamihaja et al. 2019). These land-use dynamics are leading to the emergence of trans-scalar situations, where external forces outpace local conditions of land-use change (Eakin et al. 2014) and drive increasing strain on existing land governance systems.
Land governance systems The dynamic interactions between different local and distant actors are part of the challenges of governing land use globally, primarily along with the nexus subsistence versus commercial agriculture and the nexus smallholder versus large-holder agricultural systems (Meyfroidt et al. 2020).
Challenges associated to land governance systems Explanation and corresponding literature
(C) Poverty traps and land degradation spirals in smallholder production systems Smallholder-led production systems are an important piece of current agricultural production, with 70% of the food calories in Latin America, sub-Saharan Africa, and South and East Asia produced in likely smallholder-dominated areas (Samberg et al. 2016). Literature suggests that positive spillovers can arise from the coexistence of large-scale and smallholder farming (Deininger and Xia 2016). However, large-scale investments often result in smallholders’ marginalization (Oberlack et al. 2016), leaving them without prospects outside agriculture because of the limited absorption capacity of other sectors of the economy (Li 2011). Smallholders’ challenges are mostly linked to a poverty circle in which they are embedded and often incapable of leaving. This social condition aggravates because of increasingly small plots for crop production associated with land degradation (Nhantumbo 1997, Meyfroidt et al. 2018).
(D) Institutional fragility hindering the development of a commercial agriculture that contributes to sustainable development in frontier contexts Institutional fragility is often defined as a situation in which different institutional dimensions are not progressing at the same pace and thus create internal friction and conflict during development processes (Shi et al. 2017). This fragility or weak institutional capacity is considered a challenge for developing commercial agriculture that contributes to sustainable development i.e., improve livelihoods, contribute to food security, among others. First, from a spatial planning perspective, there are often strong relationships between hard infrastructure such as roads and railways and land-use dynamics (Searle 2016, Schindler et al. 2018). For example, Meir et al. (2019) report that the lack of quality roads is a conspicuous feature of frontiers hindering their development path. Emerging or consolidated land-use frontiers, as the Amazon Region, have seen exponential growth, not only in roads but also in large-scale water projects, such as hydropower dams and navigation facilities. The Amazon Region is one of the most active frontiers of infrastructure expansion, resource extraction, and social-ecological exploitation in the world today (Ioris 2020). Transportation costs of agricultural or forestry products can be substantially modified by investments in infrastructure (Chomitz and Gray 1996). Institutions can be perceived as soft infrastructure (Fung et al. 2005). Examples are unclear contract rules for service providers, tardiness of market or broadly economic reforms, or inadequate procedures for declaring farm income.