Eva Wollenberg, Research Associate Professor
CCAFS and University of Vermont, USA
While adaptation and climate change mitigation in agriculture are usually managed at the farm, plot, or crop level, a landscape-level approach can increase agriculture’s “climate smartness.” That means achieving multiple goals – adaptation and mitigation of climate change, while also meeting agricultural production, food security, and sustainable development objectives.
Key features from a landscape perspective include (1) mosaics of land uses, and in particular assemblages of agriculture, forestry and degraded land; (2) multiple social needs and collective goods; (3) a variety of functions and processes, including ecological services (water, pollination, biodiversity, nutrient flows), economic factors (forests as safety net for bad crop years, livelihood diversity), or agroecological systems (fallow and swidden system). Additionally, landscape-level analysis and management capture a larger amount of the external costs of farming, such as waste and pollution. Finally, landscape management bridges the gap between the national and project levels that is often overlooked.
From a technical perspective, landscapes most importantly contribute to climate change mitigation through the above ground biomass of primary forests. In a landscape, we also know that land use change (usually from forest to agriculture) contributes about 18% of total anthropogenic GHG emissions, while only 10-12% is from agricultural production. Given this reality, land sparing and agricultural intensification therefore appear to be the most important approach for agriculture’s potential contribution to mitigation. Land sparing is the notion that producing more crops from less land can result in mitigation if the resulting “spared land” has the capacity to sequester more carbon or emit less GHGs than farmland.
Based on modeling, increased crop productivity resulting from the Green Revolution from 1961 to 2005 has shown about 161 Gt of avoided carbon emissions, despite higher levels of inputs that simultaneously increased emissions. In other words, the small increase in emissions was offset by the larger reduction. Similarly, another study found that a 20% increase in fertilizer for rice, wheat, and maize took about 23 million hectares out of cultivation without changing production. Both these studies build a case for the land sparing hypothesis.
Unfortunately it’s not that simple. Evidence suggests that “land sparing” alone often leads to expansion, not contraction, of agricultural lands. Similarly, we find that interventions seeking to conserve forests against the threat of agriculture have had limited success. This could be a result of misaligned incentives, a narrow focus solely on local technical interventions, or simply the complexity of multiple local and macro factors (such as population migration and climatic stresses).
Intensification can also increase vulnerability to climate change. High-yielding, input-intensive crop varieties require more fertilizers and water. Furthermore, outside infrastructure is required to maintain resources for crop production (e.g. petrochemicals). So, how intensification occurs is important, and efforts to maintain diversity and other agroecological functions that increase resilience will be beneficial.
Therefore, the context of agriculture-forest interactions and social and agroecological capacity for agricultural intensification is a key factor in developing climate smart landscapes. Landscapes afford flexibility in trade-offs between adaptation and mitigation, livelihoods and biodiversity. Understanding these trade-offs will be essential, as will appropriate institutional arrangements for landscape-level management.
Moving forward, some priorities for climate-smart landscapes are:
- Develop a better understanding of intensification, its limitations, and trade-offs for land sparing near forests, pastures, and degraded lands in different contexts.
- Identify what sustainable intensification will look like at the landscape level, using agroecological approaches for innovation in efficiency, integration, and multifunctionality.
- Identify how climate change affects key functions – is there redundancy and safety nets at different levels to ensure resilience?
- Identify institutional arrangements and incentives for coordination to achieve multiple objectives and monitor condition, from district to international level.
- Develop criteria and indicators for sustainable landscape management, enabling adaptive management and land use change.
- Target innovation, learning, and finance to the landscape level and their regionally specific contexts.
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