A Response to Breakthrough's Essay on Wildlife and Farmland
While the land-sparing/land-sharing debate drives much of the discussion around food production and conservation, Kremen argues that its emphasis on the supply side oversimplifies the issue and distracts from the solutions at hand. A demand-side approach, in contrast, would turn the focus away from yields and toward attempts to minimize consumption, waste, and inequity. Such reductions, in turn, could yield huge dividends for both humans and wildlife.
In Linus Blomqvist’s recent essay on wildlife and farmland, he uses the classic land-sparing versus land-sharing framework to discuss how to best protect biodiversity at the local and the global level. Blomqvist concludes that there are opportunities for “win-wins” between farmland productivity and biodiversity, but that ultimately, high-yield agriculture, whether conventional or organic, will mostly mean less on-farm wildlife. Thus, conserving biodiversity primarily requires a “tweaked” land-sparing strategy—i.e., protecting biodiversity in large reserves and mildly modifying intensive agriculture through crop rotations.
I agree with Blomqvist on protecting large reserves whenever possible, but disagree that the land-sparing/land-sharing perspective will help us to identify pathways for biodiversity conservation. To me, the land-sparing/land-sharing debate is dangerous because it oversimplifies key aspects influencing land use, and focuses attention away from more important issues that will determine future land use, biodiversity, and human well-being. Instead, tremendous potential exists to protect biodiversity and meet human nutritional needs by focusing on the demand side, rather than the supply-side emphasis of land-sparing/land-sharing. By shifting diets away from meat, reducing food waste, and bending the population growth curve down through voluntary family planning, we can significantly reduce humanity’s impact on landscapes, ecosystems, and wildlife. Finally, while Blomqvist and I agree that how we farm matters for both biodiversity and yields, I disagree that monocultures are always more high yielding; further, they are demonstrably far less resilient to pests, disease, and disasters than more diversified agriculture.
Land sparing versus land sharing: An oversimplified debate
The fallacy of the land-sparing/land-sharing debate is its deceptive simplicity.1 The debate centers on the assumption that there is a fixed target of production that must be met, either by high-yielding agriculture on a smaller land area, or low-yielding agriculture on a larger land area.2 Unfortunately, the world does not usually work that way. Norman Borlaug, the architect of the Green Revolution and the land-sparing concept, thought that as agriculture became more efficient and higher yielding, prices would fall, forcing less productive farmers out and reducing the overall land area devoted to agriculture. But empirical data does not support this claim. Forest economist Thomas Rudel, in his 2005 analysis of 10 major commodity crops in 161 countries, found that “the most common pattern involved simultaneous increases in agricultural yields and cultivated areas” (emphasis added). This simultaneous increase is an example of a “Jevons paradox”—as prices fall due to increased or more efficient production, demand also expands.3 Global supply chains can readily soak up the surplus supply, profiting from cheaply produced commodities like palm oil or corn, for example, to fabricate hundreds of profitable products. Thus, whenever increased agricultural productivity spikes new demand, yield increases will not lead to land sparing,4 unless accompanied by strong market-based and/or regulatory environmental safeguards that stringently restrict agricultural expansion into primary habitats.5–7
How to stabilize the agricultural land footprint
The land-sparing/land-sharing debate, by focusing on the yields and areas needed to meet a target level of food production, is missing several real opportunities to stabilize the agricultural footprint. The only real way to prevent further agricultural expansion is to reduce consumption, and its companions, waste and inequity. Such solutions are not politically popular because they push back against the growth economy, yet there are three obvious places to start that could yield huge dividends for biodiversity and for current and future quality of life.
First, we currently devote an incredibly large area to livestock production (one-third of terrestrial ice-free land surface), and devote three-quarters of croplands to growing grains that feed livestock rather than humans.8 Feed crops constitute 36% and 53%, respectively, of the calories and proteins in global crop production, yet only ~4% and ~26% of these crop-based calories and protein end up in human diets, due to vast conversion inefficiencies as nutrients move up the food chain.9 Simply reducing meat consumption by half could feed 2 billion people, reducing the burden of hunger on the planet without increasing the area under cultivation at all. As economies develop, however, they are clamoring for more meat, not less.8 In fact, this rising demand constitutes a large component of the oft-repeated claim that food demands will double by 2050.10 Food demands are not the same as food needs,11 however, and eating too much meat is a well-recognized contributor to heart disease, stroke, type 2 diabetes, obesity, and certain cancers.12,13 Reducing meat consumption by those who eat too much, stabilizing it at current levels for those who are eating the right amount (about the size of a pack of cards per person per day),8 and increasing access to meat for the 2 billion people who suffer from iron deficiency anemia14 could help to solve several global health burdens at once. Finally, reintegrating livestock into smallholder farms could help to reduce nutrient overloads produced at contained animal feeding operations, reduce the overuse of antibiotics in livestock, and return critical nutrients to the soil and to the diets of smallholder or subsistence farmers.8
Second, we currently waste 30-50% of the food that is produced annually.15 Instead of worrying about whether organic agriculture produces only 80 to 85%16 of the food produced by conventional agriculture, why not simply cut the wastage by half? That would take care of the organic-to-conventional yield gap without requiring more land, while improving conditions for biodiversity on farms17 and growing food in a more sustainable manner.18 Further, preventing food waste would also prevent wastage of all the energy, water, inputs, and labor that went into producing it. Some of these inputs, such as fertilizers and pesticides, are exerting damaging effects on our oceans and streams, our wildlife, and human health.19
Third, the growing human population also increases consumption—yet there is a large unmet need for family planning.20,21 Many families wish to reduce the number of births, but do not have the means to do so. If these unmet needs for limiting reproduction could be met even partially, human population could stabilize well below the 9-13 billion people that are currently projected for 2100.22 A number of countries, including impoverished countries like Bangladesh, have made huge strides in providing contraception to families that desire it, halving total fertility rates in two decades or less.21 Meeting these needs through voluntary family planning can simultaneously improve child and maternal health and reduce poverty.21 A population projection that compared meeting the unmet need for family planning with business as usual estimated population sizes of 7.3 billion people by 2100, rather than 10.4 billion.23 We produce enough food annually to feed today’s population of 7.5 billion with our current agricultural footprint, although many people remain hungry or malnourished due to poverty and lack of access to sufficient, nutritious food.11 Thus, policies that support the universal access to reproductive health and family planning services (e.g., Millennium Development Goal 5.B) should be a top priority not only for human development21 but also for biodiversity and environmental conservation.
The land-sparing/land-sharing debate ignores these important issues and potential solutions by focusing only on yield and area. Unfortunately, this focus plays right into the agenda of the small number of highly consolidated agribusinesses that produce agricultural inputs such as seeds, pesticides, and fertilizers. Under a biodiversity banner, agribusiness companies can further promote their products as essential for increasing yield to meet world food demands, even as evidence unfolds to the contrary.24–26 Yet due to the Jevons paradox, any yield gains are unlikely to protect biodiversity, and are more likely to fuel the overconsumption that drives habitat conversion.
Agricultural practices, yields, and biodiversity conservation
In agreement with Blomqvist, how we farm matters, both for biodiversity and for production, and win-win opportunities do exist. Further, any agricultural use will markedly change biodiversity in a region, and often impoverish it;27,28 thus, stabilizing the agricultural footprint is the critical first step for biodiversity conservation (i.e., no more expansion, particularly into primary habitats that are rich in biodiversity).8,19
Assuming that we could stabilize the existing agricultural land footprint primarily by reducing consumption (as described above), then what practices will promote biodiversity while maintaining sufficient agricultural productivity? I believe there are three main components to focus on:
- Create a favorable agricultural matrix that promotes wildlife dispersal between protected areas, which is very important to reducing long-term negative effects of isolation, such as inbreeding. Developing a favorable agricultural matrix could be accomplished by strategically creating corridors of native vegetation surrounded by or interdigitated with the most hospitable types of agricultural habitats, such as agroforestry,29 silvopastoral,30 or other diversified agroecological systems.31
- Use agroecological methods in the agricultural matrix that rely on the underlying biodiversity and ecosystem services, and that reduce negative impacts of agriculture on adjacent habitats and downstream regions.18,31–33 Primarily, this involves reducing pollutants like pesticides and excess fertilizer that can kill wildlife or cause dead zones in lakes and oceans. For example, intercropping and crop rotation reduce the concentration of a given crop in space and over time and thus the crop’s attractiveness to pests. In turn, insectary strips, polycultures, and hedgerows provide habitat and resources for natural enemies of crop pests. These techniques can greatly reduce the need for pesticides,34–36 which are sometimes overused and thus add costs to farm budgets without improving yields.24,26,37
- Maintain productive, sustainable agriculture that supports livelihoods of local people living in the vicinities of protected areas. Agroecological methods, such as agroforestry, integrated pest management, and livestock integration, can substantially increase yields for people formerly practicing either conventional or subsistence agriculture across the board for a wide variety of crops.38,39
Finally, it is necessary to push back against Blomqvist’s notion that only intensive monocultures can be highly productive, and against the claim that they are resilient. There is strong evidence that increasing plant diversity in crop, forage, and forestry systems increases yields,40 and that when yield gaps occur, they can be minimized or eliminated by agroecological methods that diversify the system, such as intercropping, cover cropping, and crop rotations.35,41–44 In some systems, even removing land from production to create wildlife habitat has been shown to benefit production by increasing ecosystem services like pest control or pollination.30,45,46 Finally, compared to conventional systems, these agroecological methods increase resilience to drought, pests, diseases, floods, hurricanes, and climate change,31,47–49 and help to preserve the sustainability of the system by maintaining soil organic matter, water infiltration and holding capacity, pest and disease control, pollination services, etc.18
Blomqvist is correct that there are always trade-offs. However, the land-sparing/land-sharing debate focuses on the wrong set of trade-offs. We should instead be asking whether to allow grazing lands and grain production for livestock to eat up the remaining biodiversity-rich habitats, or instead, work on promoting diets light on meat. Whether to continue wasting 30-50% of the food that we laboriously produce, or take steps needed to alleviate food waste. Whether we really want to live on a (hot and crowded) planet containing between 9 and 15 billion people, or instead, increase efforts to provide voluntary family planning for all. If we worked on these fronts, then when we sometimes must take a small yield hit41 to produce agriculture in a more sustainable and wildlife-friendly manner, it will not be an issue. And my dream of a vision that “most, if not all, conservationists could get behind,” of “large protected areas surrounded by a relatively wildlife-friendly matrix,”1 could indeed become a reality.
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Claire Kremen is a professor of conservation biology at University of California, Berkeley, where she also co-directs the Center for Diversified Farming Systems and the Berkeley Food Institute.
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