Competition for land resources is intense, with growing demand for food and resources to support humanity. Despite this, global agricultural area has significantly declined over the past two decades due to socio–political trends, market changes and environmental degradation. Although expensive, restoring degraded lands that are no longer contested for agricultural use due to low productivity may present a major conservation opportunity with minimal social or political opposition. Here we present a new perspective for conservation that highlights the potential conservation value of uncontested lands. We highlight key factors that make lands uncontested, define an approach for evaluating costs and benefits on uncontested land parcels and propose methods for identifying these lands.

Land acquisition constitutes a core tool for delivering conservation benefits. In many parts of the world, acquiring land represents the principal pathway for either changing or preventing a change in the land use of a particular area. These actions are typically intended to avoid conversion or degradation of natural habitats, but increasingly include the restoration of degraded lands to deliver carbon sequestration. Land acquisition is a land-conservation pathway that can be facilitated by both government and non-government actors independently or in public–private partnerships. Globally, private land trusts have acquired millions of hectares of land, particularly in developed countries such as the United States and Australia, including many lands that were acquired for conservation through public–private partnerships.

Fig.1 Annual costs and benefits of acquiring and restoring land
Fig.2 Global changes in agricultural and pasture land.
Fig.3 Classification of uncontested lands in the context of low- and high-productivity land.

Costs versus benefits of conserving uncontested lands
Investment in uncontested lands for conservation requires a framework to assess the benefits delivered from acquiring and restoring uncontested areas against the costs of doing so. We have identified two economic characteristics of uncontested land that may make it attractive as a target for conservation.
Fig. 4: Potential cost patterns of four restoration project scenarios.
Benefits of ecological restoration of uncontested lands
To assess whether the costs on acquisition and potential restoration of uncontested lands are outweighed by the benefits, we need to understand what may be achieved through a level of investment in restoration. The requirements for investment in ecological restoration of an area will likely depend on what may recover there without active intervention, its proximity to sites that can facilitate recolonization and its relative degree of degradation

Published in Nature Sustainability, Volume 3, Issue 1, January 2020
Potential of uncontested lands
Restoring degraded landscapes for conservation purposes can involve transaction costs to acquire the land in the first place. McDonald-Madden and colleagues propose a framework for prioritizing uncontested lands that can provide ecosystem services without those costs.