A planet torn between unifying and fragmenting

Since humans began to have some control and dominance over natural resources, we have constantly disputed what to do with them. While we didn't always think about what to do responsibly, the different ways in which we have historically possessed nature have led us to total chaos. Nowadays we live in crisis - not only environmental, but also climate and social - because we do not know how to relate sustainably to nature and its resources. In the eighties, this situation became even more evident and people began to talk about the clear decline of biodiversity; since then we have been concerned kinda more to keep it.

Between sharing our space with the rest of nature or segregating everyone to their proper location, a debate has arisen -approximately fifteen years ago- that is latent today and has no simple answer. Although it is difficult to know its exact beginning, these positions definitely emerged after - and in response - to a discourse that industrialized hunger: how beneficial was the Green Revolution, and did it really end hunger as it said it did?

The answer is obvious: no. To contextualize a little, let's start by saying that the Green Revolution was the watershed of the industrialization of agriculture. From this point on, the introduction of agricultural machinery, pesticides, irrigation systems and varieties resistant to extreme climates and conditions was the norm. This was under the assumption that traditional agriculture was not productive enough, and therefore, we were never going to achieve a production capable of ending world hunger. However, the Green Revolution did manage to produce more food. In fact, it produced so many that today almost half of the agricultural products that exist are wasted. It produced so many that the nutritional quality dropped and we began to consume cereals that are practically just carbohydrates and no vitamins or essential amino acids (Sands et al. , 2009). All of the above made it clear that the problem was not hunger, but rather the terrible distribution of wealth. Hand in hand with this industrialized agricultural production came expansion, clearing and the loss of habitat and biodiversity. We know that today a third of the planet's emerging areas belong to conventional agriculture (Díaz et al. , 2019) and we also know that 70% of the food we consume is produced by the world's peasantry with 30% of the available land (ETC Group, 2017). These data are contradictory, or perhaps rather, they are proof of the gap that exists between conventional agriculture and people's diet.

While we can't say that the ultimate objectives of the Green Revolution were to profoundly harm the planet and lie to the people who believed in it, this is what ended up happening. However, with this problem - environmental, social and climate crisis - already in the face, strategies began to be sought that could minimize these “trade-offs”, that is, advantages and disadvantages between the relationship between agriculture (essential for life) and biodiversity (also essential for life). For a moment, the scientific community believed that they were two incompatible concepts, until two ways of understanding this intersection emerged.

On the one hand, there are those who defend a position called Land Sparing which involves intensifying agriculture in well-defined areas so that we can then allocate even larger areas for the pristine and untouchable conservation of biodiversity. On the other hand, there are those who defend a contrary position known as Land sharing which speaks of the unification of small-scale and under-intensified agriculture with the wild environment. It seems that choosing a position from this point in the text can be simple. Many of us would say that intensifying a production area would be a mistake, since it is similar to the scenario we have been experiencing lately. Some others, we would say that the species that inhabit the planet are not equally functional ecologically speaking, so build a Continuum of nature could threaten their survival. As emphasized above, it's not a simple debate. We will dissect these ideas to understand why it is not trivial to choose one or the other, or perhaps neither, or also, both.

What is a land limit? Isn't this just a human invention? Nature knows no limits: some birds migrate, pollen and seeds are transported over enormous distances, some mammals are nomadic, others simply travel kilometers and kilometers daily, while the largest being in the world is a fungus that connects entire forests underground, regardless of borders. Nature does not recognize the limits of natural parks or ecological reserves, so it is illusory to think of compacting nature into a delimited area, however large it may be. One of the strongest critiques of the position of Land Sparing implies the little connectivity that can exist between two areas of pristine nature. As Claire Kremen mentions, this position “does not assess the long-term consequences of isolating species in protected areas surrounded by inhospitable matrices” (Pearce, 2018) these matrices are inhospitable plots of conventional agriculture, cities, even a road that divides two natural areas, a tourist project and so on. A real consequence of the fragmentation of the territory is extinction. Situation that has characterized the last few centuries on planet Earth.

On the other hand, a point in favor of Land Sparing The fact is that many endemic species are extremely fragile, so introducing into their habitat -possibly already remaining- a productive activity -however sustainable- such as an edible forest or an agroecological plot, could completely disturb their environment to the extent of -also- leading to the extinction of the species, and suffice it to say that many species are totally incompatible with agriculture, so the above would not represent an isolated case.

What about species that are compatible with agriculture? This is a problem for the land sparing. The alienation of pollinators from crops is a serious situation that threatens the food security of any community. If we scale the above to a landscape scale, it also threatens several ecosystem provision services, since the presence of these organisms not only provides us with more than 90% of our food (FAO, 2015) but they also promote pest control, as well as the dispersion of seeds and pollen.

Sometimes this debate is a matter of scales. What do we want? A lot of food produced quickly or food that is slow but stable in the long term? Although no one doubts that the productivity of a conventional plot (or one located in a scenario of Land Sparing) is much higher in a short period of time -almost immediate-, long-term productivity will be much higher under a strategy land sharing. The above represents a clear example for Coffee plantations and cacaotals of the world (Tscharntke et al. , 2011). Although coffee from the sun, grown in a highly intensified monoculture, is very productive in the short term, it is completely dysfunctional in the long term. Not only does soil erode and stop being fertile, but pests kill crops. On the other hand, a shade coffee plantation cultivated on an agroecological plot (Land sharing) may not be even half as productive as the conventional one, however, it generates long-term benefits such as ecosystem stability that allows the owners of the land or the peasants who care for that crop to survive on the field.

Sometimes this debate is also a matter of analyzing what we mean by conservation priority. We have several metrics for understanding biodiversity: on the one hand there is wealth, which tells us how many different taxonomic groups we have per unit area, and on the other hand, there is abundance, which tells us how many individuals we have per taxonomic group. While the strategy of Land sharing focuses on species richness, the Land Sparing focuses on abundance. And neither is better than the other, they are just two ways (which should not be studied in isolation) of understanding biodiversity. Let's see why: in a permeable matrix, where connectivity between conservation areas is high, we are more likely to find a larger number of species even when their relative abundance is low. In an impermeable matrix, that is, where connectivity is low because the landscape is fragmented by intensified services, it is more likely that in these very well preserved, but isolated areas, there will be more numbers of a few species than different species in themselves (Soga et al. , 2014; Sidemo-Holm et al. , 2021).

These last two examples make it clear to us that the real approach to this debate cannot be superficial. There are factors of all kinds that could allow us to discern one strategy or another, however, nature - as well as its interactions - very rarely behaves in a linear way. Both the temporal and spatial scales, the type of ecosystem and seasonality play a very special joint role in determining the best posture for a location. Talking about global strategy would definitely be a mistake, or at least, a very biased decision. And let's keep in mind that we haven't included the sociocultural aspect in the map. Personally, I will save my opinion so as not to err on objectivity, since this debate is the result of a strong political and ideological tension - as well as an ecological and conservationist one, of course - of its defending parties, as it emerges in opposition to the sharpest form of industrialization of agriculture. Finally, it seems to me that the argument between one way of understanding conservation and production is not solvable in the face of a mentality embodied in the past of our history. This debate opens an incredible window of opportunity to name the world and the relationship with the environment that as humans we do want to have and do want to build., which I imagine that for all our readers, will be living in a world compatible with life.

About the author:

Sandra is Executive Editor in Toronto. He studied biology at the UNAM. He loves to read and be in nature.

References:

• Diaz, S.; Settele, J.; Brondízio, E. et al. (2019). The Global Assessment Report on Biodiversity and Ecosystem Services. Available in: https://ipbes.net/sites/default/files/2020-02/ipbes_global_assessment_report_summary_for_policymakers_es.pdf
• ETC Group. (2017). Who will feed us? Available at: https://www.etcgroup.org/sites/www.etcgroup.org/files/files/etc-quiennosalimentara-2017-es.pdf
• FAO. (2015). Healthy soils are the basis for healthy food production. Available in: https://www.fao.org/soils-2015/news/news-detail/es/c/277721/#:~:text=Se%20estima%20que%20el%2095,a%20la%20producci%C3%B3n%20de%20alimentos.
• Pearce, F. (2018). Sparing vs Sharing: The Great Debate Over How to Protect Nature. Available at: https://e360.yale.edu/features/sparing-vs-sharing-the-great-debate-over-how-to-protect-nature
• Sidemo‐Holm, W., Ekroos, J., and Smith, H. (2021). Land sharing versus land sparing-What outcomes are compared between which land uses?. Conservation Science And Practice, 3(11). doi:10.1111/csp2.530
• Soga, M., Yamaura, Y., Koike, S., and Gaston, K. (2014). Land sharing vs. land sparing: does the compact city reconcile urban development and biodiversity conservation?. Journal of Applied Ecology, 51(5), 1378-1386. doi: 10.1111/1365-2664.12280
• Tscharntke, T., Clough, Y., Bhagwat, S.A., Buchori, D., Faust, H., Hertel, D., et al. (2011). Multifunctional shade-tree management in tropical agroforestry landscapes - A review. Journal of Applied Ecology, 48, 619-629. https://doi.org/10.1111/j.1365-2664.2010.01939.x