The Sustainable Intensification of Agriculture

Climate change, water scarcity, and the limited availability of arable land while demand is on the continuous rise, make it clear that we need alternatives to conventional farming. With the Earth’s population predicted to rise to nine billion by 2050, we must increase the yields of global agriculture without environmental degradation or cultivating more land. Producing 70 percent more food for an additional 2.3 billion people by 2050, while at the same time combating poverty and hunger, using scarce natural resources more efficiently, and adapting to climate change are the main challenges world agriculture will face in the coming decades.

Given these challenges, current approaches are or may become unsustainable. We must find new methods that address all elements of the agricultural system, encompassing better soil and land management, as well as the enhancement of soil structure and biodiversity. The sustainable intensification of crop production approach focuses on the need to feed a growing population while coping with an increasingly degraded environment and uncertainties resulting from climate change. This concept provides opportunities for optimizing crop production per unit area, taking into consideration the range of sustainability aspects including potential and/or real social, political, economic and environmental impacts.

Securing the food supply requires a coordinated effort with a clear vision of both the challenges and the potential of proposed solutions. New efforts must be resource efficient, or in other words, to produce more with less, primarily with regard to soil and water, but also with regards to other inputs such as fertilizers, plant protection products, energy, and labor. The realization of this goal—that clearly depends upon the ability to activate the knowledge transfer needed to support and strengthen the rural communities and improved collaboration in the value chain—would not only contribute to competitiveness and economic sustainability, but would support the investments in ecosystem resilience necessary to sustain future productivity and the productive capacity of future generations.

Biodiversity determines health and resilience of ecosystems. In fact, biodiversity enhanced in uncropped field margins supports multiple other ecosystem services such as erosion control, soil formation, nutrient cycling, pollination, and biological control, as well as climate regulation.^1-3

Biodiversity loss is a serious threat to food safety and health. Habitat loss and fragmentation are among the most important elements of this threat.^1,2,4 These translate into a population of ‘smaller size’ and ‘greater isolation.’ Size and isolation limit species’ genetic variation, reduce their potential of evolutionary adaption, and increase the possibility of extinction, which climate change may further accelerate.⁵

Surprisingly, the policy framework on biodiversity considers the lack of landscape connectivity in a marginal way. Environmental legislation on biodiversity is fragmented and mainly related to species and spaces protection (e.g., specific species, habitats, and resource frameworks), and rarely includes ecological corridors or systematic opportunities of leveraging the cultural and natural heritage of ecological systems.

 

Innovation vs. Innovative Implementation

To implement the learning of an agricultural innovation requires itself an innovative process. Learning proceeds through stages, but for that to happen, the farmer needs to be motivated to devote the necessary effort.

Motivation can come from individuals or be imposed from the outside, most often by markets or regulation. In both cases, individuals need to be aware of the new solution and of the potential reward systems attached.

As the depth of intrinsic interest and curiosity increases, awareness turns into understanding, and learning barriers are breached and progressively removed throughout practical optimization and refinement.

In conclusion, the real implementation is only happening when effective knowledge transfer systems can enable farmers to put forward the theoretical innovation, and the learning process is only complete when deep learning drives the understanding, turning into commitments first, and then into actions, unleashing a virtuous cycle.

For this reason, implementation may sometimes generate ‘innovative changes’ decades from the genesis of the innovative idea.

 

The Solution: Sustainable Intensification as a New Production System

The continued development of a sustainable intensification of agriculture is essential to maintain the future quality and supply of agricultural products, while respecting the integrity of the land and the people who work it. Improving farming techniques—the way we till, rotate crops, cover the ground, fertilize, and handle plant protection products—can contribute significantly towards enhancing soil and water conservation, as well as biodiversity.^6,7 At the same time, using available land more efficiently (i.e., zero tillage) can help us abate greenhouse gas emissions in agriculture, avoid further destruction of natural habitats, and contribute to stored soil carbon. Improved use of un-cropped areas can halt habitat loss while landscape connectivity can avoid fragmentation and species isolation that, through a reduced evolutionary adaption, increases the possibility of extinction.⁶

Sustainable intensification builds on combining and creating synergies between existing individual solutions, while selecting those elements that provide multiple benefits to the various societal challenges. In recent history, we have had green revolution policies that created production systems focused on increasing output. Policies were first meant to open markets and increase opportunities for farmers to improve their income and social status. More recently, policies are aimed at reducing environmental impacts. The future will be reserved for production systems that are able to produce multiple benefits responding to more than one societal challenge. The value added of these new solutions is to find the right combination of elements that reply to this objective.

While sustainable practices are making inroads into farming communities, work is needed to make them more widespread and to adapt them to local needs and indigenous knowledge. We need convincing evidence that the methods produce quality crops in sufficient quantities, and that this approach can support a competitive and healthy rural community. Research and development, investment in new technologies, and strategized agricultural policy, as well as capacity-building to put these tools into practice, will help support a competitive farming sector that is able to balance productivity with the protection of natural resources.

A number of projects have been implemented by several different multi-stakeholder platforms, such as LIFE+ Agricarbon and LIFE+ ClimAgri that support the transformation of our agricultural systems towards resource-use optimization, ecosystem resilience, knowledge transfer, and climate adaptation.^8,9 Within these projects we explored: (i) Conservation Agriculture (CA) from the farmer’s perspective and determined how guidelines are best applied in the field; (ii) multifunctional landscape issues, and, (iii) the integration of the protection of biodiversity with that of soil and water through vegetative strips that not only provide valuable habitats, but also capture runoff and prevent erosion from fields, while supporting landscape connectivity. Such approaches are an integral part of the Sustainable Intensive Agriculture of the future.

Overall, data collected from the above projects shows that the combination of intensive farming and sustainability practices can promote an economically viable system of intensive agricultural production. It meets the demands of the coming decades while reducing pressure on habitat and enhancing the conservation of water and soil. These findings also suggest that a range of approaches is required that are specific to crops, climates, and cultures found around the globe.

These broad avenues of scientific research are observed in light of social, economic, and political considerations. We nonetheless believe our experience shows that this form of sustainable intensification creates many opportunities for continued improvement in agricultural productivity, environmental stewardship, and human well-being.

 

Field Margins: One Element of a System to Address Many Challenges in Agriculture

We need biodiversity policy to go beyond the identification and conservation of species and spaces by considering instead the link between biodiversity in agriculture and the role of farmers as custodians of this biodiversity.

In this direction, the concept of habitats based on vegetation types should give way to inter-connected functional habitats, adapted to local land uses and opportunities for conservation. The restoration of landscape connectivity would be a valid measure to generate diversity, evolution, and improved landscape adaptation.¹⁰ This would help enormously in terms of anticipation and prevention (e.g., act well before the genetic diversity and the evolutionary potential of the species have been eroded: once genetically impoverished, populations can count on a very limited adaptability).

Field margins, and other rural landscape features, can make a significant contribution to the restoration of landscape connectivity and the achievement of food security without compromising resource conservation. Indeed, the management of field margins, or other uncropped areas next to or near fields, is one of the most important environmental assets that a farmer can provide. Today, it is widely acknowledged that field margins are crucial for the protection of soil and water and, where appropriately managed, boost biological diversity in farming landscapes.^11-13

The intervention of farmers to use marginal land, traditionally ignored, to produce multiple effects for cropping areas and simultaneously for the environment is, in itself, an innovation in agricultural production. Further synergies sought with cropping technologies and considerations of the landscape and connectivity of green infrastructures are a further contribution that transforms the farmer from a resource-consuming actor to a custodian of land and landscapes. Hence, farmers’ social roles and positions need to be reconsidered.

Agricultural landscapes are primarily dictated by the activities of farming communities making their living within the physical constraints of the land. They vary with geography, topography, cropping systems, and intensity of management. In most farming systems, for example, the landscape presents a myriad of cultivated and uncultivated elements, separated by linear features including field margins, verges, and watercourses. These linear features create the rich mosaic of farmers’ fields, defining the diversity of agricultural landscapes across the regions.

Field margins are typified by having some form of boundary structure—typically a hedge, fence, wall, bank, ditch, drain, or water course. In most instances, this is accompanied by some form of associated herbaceous vegetation adjacent to the crop. A margin strip is any clearly defined strip established in the field or at the edge of the field, between the crop and the boundary. The purpose of this area may be for access or for wildlife and environmental objectives and may have agronomic, recreational, or cultural functions.¹⁴

In recent years, there has been a close look at the positive roles played by field margins, hedges, and ponds on farmland. New approaches to creating and managing these areas have shown how they can deliver greater benefits for the environment and for the public good.^1-3

Today, it is broadly acknowledged that measures to enhance farmland biodiversity and to protect essential resources—primarily clean water and soil—are as important as the need for food and feed production. Indeed, they are seen as key to the sustainability of such production systems.^12,15 Not surprisingly then, the focus of a number of recent studies has been the development of proactive techniques to create and manage areas of farmland biodiversity.¹⁶ This scientific research and detailed monitoring has shown that it is possible to significantly enhance beneficial insects, biodiversity, and environmental protection, while enabling farmers to retain practical options for increased productivity and the profitable use of farmed lands.^1,4,14,17

Although a better understanding of the complex interactions between fauna and flora, cropped and non-cropped areas, and semi-natural habitat and crops is still needed, there are some noteworthy observations:¹⁰

• Sown strips of selected perennial species, between arable fields and alongside hedges, can supplement and enrich existing natural herbaceous flora. This can provide potential environmental benefits for plant species diversity and supporting larger insect populations, along with agricultural benefits for improved weed management.
• Positive management of flora on field margins and banks of watercourses adjacent to crop fields can have substantial benefits, such as soil erosion and enhanced water quality.
• The importance of field margins and hedges in providing habitat and food sources for farmland birds has been researched and highlighted. It has been shown that modification of field margin management—specifically, to help target species of declining farmland birds—may help in their conservation.
• These land features are also important for pollinating insects, such as bees and butterflies. Studies have indicated that relatively small areas of carefully selected and sited farmland specifically managed for biodiversity enhancement or environmental protection can provide significant gains and meet clear objectives, with little or no impact on physical production from the farmed area.

Although counter-intuitive, field margins are beneficial for agricultural production: many beneficial predators, such as spiders and ground beetles which feed on a variety of foods, especially traditional crop pests such as aphids, are dependent upon field margins for part of the year.^17,18 The high number of invertebrates provides food for farmland birds and mammals, such as bats. Field margins and hedges are also important as refuges for arthropods in winter, and may even influence the soil macrofauna, notably earthworms, which can be beneficial for the quality of the soils.^14,15,19,20

Importantly, field margins may also influence the flow of nutrients and water within agricultural landscapes.³ Studies have shown that margins alongside watercourses can act as buffers to stop the movement of soil from fields to adjacent watercourses and wetland habitats, including rivers, streams, ditches, and marshlands. This, in turn, can help prevent any contaminants within the soil particles from reaching the watercourse.^11,21,22

With this new emphasis on environmental protection, combined with a renewed desire from consumers to understand and appreciate the production systems from which their food comes, farmers are starting to be recognized as custodians and conservers of their land and providers of an irreplaceable resource managed for the public good.

In addition to measures that can assist farmers with the creation of beneficial field margins, further initiatives should ensure that other areas of non-farmed land, such as road and rail embankments, are fully utilized to achieve the best possible environmental benefit.

Furthermore, initiatives to encourage the public to manage homes and gardens towards providing habitats for pollinators and others could prove entirely complementary to the actions being taken on farms.

 

Conservation Agriculture: A Breakthrough in Three Simple Steps

In general, conventional farming practices are based on the tillage of soil in order to control weeds and prepare a proper seedbed. Unfortunately, the implements utilized to plough degrade topsoil. The UNCCD estimates that 12 million hectares per year of productive land are being degraded globally, with some of this degradation being induced by agricultural practices.²³

Tillage-based agriculture is unable to deliver many environmental ecosystem services due to its high and cumulative externalities, as well as its inability to serve the needs of resource-poor farmers. Tillage degrades the natural soil structure and depletes soil organic matter, as well as the associated soil life and biodiversity, along with many of the soil-mediated ecosystem functions that provide, regulate, and protect environmental services.^6,7,20  Ploughing also causes many off-site damages to infrastructure (e.g., sedimentation in water courses and dams), in downstream watercourses, and in water bodies (due to the pollution with sediments, nutrients, and agri-chemicals that are diluted in water or fixed in the particles of soil).

In addition, soil tillage causes a decrease in soil quality due to organic matter loss. Certainly, tillage operations significantly reduce soil fertility and productivity. Conventional agriculture CO₂ emissions originate from ploughing operations, for which high power tractors are needed at almost full capacity, consuming large amounts of fuel. But, ploughing also promotes the contact between soil organic carbon and atmospheric oxygen. This interaction results in a microbiological oxidation that leads to the formation of CO₂ emitted into the atmosphere. By substituting conventional practices with conservation practices, carbon emissions can be substantially abated.⁶

Conservation Agriculture (CA) is a so-called emerging agro-science and encompasses techniques that minimize or eliminate tillage and, thus, maintain a vegetative cover that protects soil from degradation.

CA principles emanate from conservation tillage (CT), which includes no tillage (NT), reduced tillage (RT), and groundcovers (GC) in perennial crops. Nevertheless, CA is not the same as CT. Certainly, CA goes beyond CT, and is defined by three linked core principles that must be jointly applied to create synergies: minimum soil disturbance, permanent organic soil cover, and crop rotations. CA relies on NT as the best practice for arable crops, and on GC for perennial crops.

Therefore, a proper management of crop residues is key to CA. Crop residues are the tools through which many of the benefits of CA are reached.⁶ Maintaining the straw over the soil fulfils a series of functions that help agriculture to be turned into a sustainable activity:

• Protect soil against erosion: crop residues are a physical barrier to the impact of drops. These impacts can disaggregate soil particles that move downstream easily. Residues also block wind erosion.
• Wildlife refuge: straw is a refuge itself for many microorganisms, insects, small animals, and birds.
• Physical barrier to downstream movement of water, soil particles, and contaminants.
• Increase of organic matter level: vegetal residues are decomposed by soil microorganisms and become part of the soil, increasing its organic matter level and providing soil a better structure by making up more stable soil aggregates.
• Carbon sequestration: soil acts as a sink/store of C if crop residues are not removed from a field or burned.
• Improved water balance: leaving crop residues in the plot prevents solar radiation from reaching the ground and, therefore, evaporation decreases.

Over the past forty years, empirical and scientific evidence from different parts of the world in the tropical, sub-tropical, and temperate regions has been accumulating to show that CA, translated into locally devised practices to address prevailing ecological and socio-economic constraints and opportunities, can work successfully to provide a range of productivity, socio-economic, and environmental benefits to producers and society at large.⁷

There is a need to make an effective technology transfer to farmers and technicians using a combination of scientific and practical expertise, in order to avoid abandoning the application of CA techniques due to a lack of training.

Programs at the national and regional levels should be developed in order to adapt existing knowledge to local conditions. Incentive funds should also be implemented wherever possible.

The implementation of long-term agronomic research projects on CA systems would contribute to the improvement and adaptation of CA to local conditions, and would reinforce already running programs.

 

Findings

 

1. Projects have demonstrated that landscape connectivity and CA can indeed protect ecosystem resilience. Over time, biodiversity is enhanced, soil health and structure improved, and soil erosion and diffuse water pollution reduced. In the long run, labor and energy costs decline, and inputs are reduced to optimal levels.
2. The benefits to the environment and the potential rewards to society and to future generations of farmers are substantial. It is clear that sustainable intensive agriculture can be more widely adopted. We have also learned that no single set of technologies and practices work in all places. Approach must be tailored to the local landscape conditions and indigenous knowledge. Halting the loss of biodiversity and reducing soil and land degradation is a shared responsibility.
3. There is room for improvement in current policies and incentives to promote investments in agriculture. It is possible and feasible to enhance the resilience of our ecosystems by helping farmers through multi-stakeholder platforms, inclusive of different roles and professional abilities.
4. The agriculture of tomorrow has to solve a number of very complicated equations where outputs in terms of food products, raw materials for renewables, biomass for energy, carbon sequestration and climate change mitigation, biodiversity and public goods need to rise, while inputs in natural resources, labor, and external inputs need to decrease.
5. Adaptation of agricultural practices to these new challenges has started with scientifically-based solutions and approaches being developed. However, there is no one-size-fits-all practice that will deliver on all objectives and do so immediately. New approaches need to be considered with local specificities and conditions in mind.
6. The two examples mentioned here: field margins and CA, should be integrated with other solutions to deliver a mix of sustainable intensive agriculture that is suitable to and delivers on the objectives for the area where the farmer operates.
7. Field margins have been proven to provide multiple benefits to agriculture, the environment, and the society in general, however their implementation is not straight forward as there are numerous criteria of geography, climate, soil morphology, biodiversity, etc., that need to be taken into account.
8. CA produces a number of benefits for the environment, for the conservation of soil and water resources, and for climate change mitigation and adaptation, however, its application is dependent upon a number of natural conditions that need to be met to be able to produce these benefits.
9. The mix of approaches, technologies, and solutions needs to be finally judged through the balanced filter of sustainability, which will weigh the environmental benefits with social impacts and the economic sustainability of the approach.

Final thoughts

 

Sustainable intensification is moving towards agricultural systems that actively contribute to higher food, feed, fiber, and fuel production, and simultaneously help to protect biodiversity, improve soil health and fertility, clean and regulate water supplies, and enhance other ecosystem services.

Growers should not only be stewards of their croplands, but also of non-cropped habitats in and around cropped land—preserving and managing these habitats to extract benefits for crop production—and should be supported in this by multiple actors.

At the same time, simply engaging growers with technologies will not guarantee the desired and overall value creation at ground level. In order to understand the relevance of soil management and biodiversity conservation and then take conducive actions, growers need support from multiple actors: agronomists, input providers, banks, and farm insurance agencies. Value chain engagements, local community involvement, and government support are also recognized to be crucial.

The sustainable intensification of agricultural practices is a team effort and only possible if socio-economic means facilitate simple and practical implementation linking progressive growers to value chain partners, and up to consumers, in order to reward the best efforts.

 

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