The world needs better management of water, soil, nutrients, and biodiversity in crop, livestock, and fisheries systems, coupled with higher-order landscape considerations as well as circular economy and agroecological approaches.
CIMMYT and CGIAR use modern digital tools to bring together state-of-the-art Earth system observation and big data analysis to inform co-design of global solutions and national policies.
Our maize and wheat genebanks preserve the legacy of biodiversity, while breeders and researchers look at ways to reduce the environmental footprint of agriculture.
Ultimately, our work helps stay within planetary boundaries and limit water use, nutrient use, pollution, undesirable land use change, and biodiversity loss.
Corn is one of the most widely produced crops in the world, and Mexico is home to at least 60 recorded unique landraces, the traditional, locally adapted strains. Preserving these ancient varieties is key for future sustainability, explains geneticist Martha Willcox, who works with the Mexico-based International Maize and Wheat Improvement Center (CIMMYT) to conserve the genes of dwindling crops. But left in the hands of aging campesinos, ancestral maize is at risk of becoming extinct. And the consequent loss of biodiversity, the FAO warned in its 2010 report, will have a major impact on the ability of humankind—which will number nine billion by 2050—to combat food insecurity in the face of climate change.
Some of Mexico’s favorite dishes are taking on a new hue with blue corn chips, blue tortillas or blue tamales. But should breeders, millers, processors and farmer organizations invest in expanding the production of blue maize and blue maize products? Are consumers really interested, and are they willing to pay more?
CIMMYT markets and value chain specialist Trent Blare explains, in one minute, the results of his study, which gives insight into Mexican consumers’ preferences and demand for blue maize tortillas. Consumers near Mexico City perceived blue maize tortillas to taste better and were willing to pay up to a third more to buy them for special family events or to consume them in a restaurant .
When disease outbreaks occur, the impacts can be devastating. In the 1840s, the Irish potato famine, caused by the fungal disease late blight, killed around one million people and caused another million to emigrate.
The recent invasion of desert locusts throughout the horn of Africa – the worst in decades – shows how vulnerable crops are to pests as well.
The desert locust is one of the most destructive pests in the world, with one small swarm covering one square kilometer eating the same amount of food per day as 35,000 people. The outbreak could even provoke a humanitarian crisis, according to the FAO.
How does climate change affect pests and diseases?
Climate change is one factor driving the spread of pests and diseases, along with increasing global trade. Climate change can affect the population size, survival rate and geographical distribution of pests; and the intensity, development and geographical distribution of diseases.
Temperature and rainfall are the big drivers of shifts in how and where pests and diseases spread, according to experts.
“In general, an increase in temperature and precipitation levels favors the growth and distribution of most pest species by providing a warm and humid environment and providing necessary moisture for their growth,” says Tek Sapkota, agricultural systems and climate change scientist at the International Maize and Wheat Improvement Center (CIMMYT).
However, when temperatures and precipitation levels get too high, this can slow the growth and reproduction of some pest species and destroy them by washing their eggs and larvae off the host plant, he explains.
This would explain why many pests are moving away from the tropics towards more temperate areas. Pests like warmer temperatures – but up to a point. If it is too hot or too cold, populations grow more slowly. Since temperate regions are not currently at the optimal temperature for pests, populations are expected to grow more quickly in these areas as they warm up.
Crop diseases are following a similar pattern, particularly when it comes to pathogens like fungi.
Movement towards the earth’s poles
Research shows that since 1960, crop pests and diseases have been moving at an average of 3 km a year in the direction of the earth’s north and south poles as temperatures increase.
Tar spot, a fungal disease native to Latin America, which can cause up to 50% of yield losses in maize, was detected for the first time in the US in 2015. Normally prevalent in tropical climates, the disease has started emerging in non-tropical regions, including highland areas of Central Mexico and many counties in the US.
Maize-producing counties in the USA vulnerable to tar spot complex (TSC) calculated based on climate similarity. Khondoker Mottaleb et al. 2018
The southern pine beetle, one of the most destructive insects invading North America, is moving north as temperatures rise and is likely to spread throughout northeastern United States and into southeastern Canada by 2050.
Wheat stem rust was reported by the Greeks and Romans, and the latter sacrificed to the gods to avoid disease outbreaks on their wheat crops. Photo: CIMMYT/Petr Kosina
Wheat rusts, which are among the greatest threats to wheat production around the world, are also adapting to warmer climates and becoming more aggressive in nature, says Mandeep Randhawa, CIMMYT wheat breeder and wheat rust pathologist.
“As temperatures rise, larger quantities of spores are produced that can cause further infection and could potentially result in pathogenic changes through faster rate of their evolution.”
Scientists recently reported that stem rust had emerged in the UK for the first time in 60 years. Climate changes over the past 25 years are likely to have encouraged conditions for infection, according to the study.
Rising CO2 levels
Rising carbon dioxide (CO2) levels could also affect pests indirectly, by changing the architecture of their host plant and weakening its defenses.
“Elevated CO2 concentrations, as a result of human activity and influence on climate change, will most likely influence pests indirectly through the modification in plant chemistry, physiology and nutritional content,” says Leonardo Crespo, CIMMYT wheat breeder.
Despite high confidence among scientists that climate change will cause an increase in pests and diseases, predicting exactly when and where pests and diseases will spread is no easy task. There is significant variation between different species of pests and types of pathogens, and climate models can only provide estimates of where infection or outbreaks might occur.
Keeping pests and disease pandemics at bay
To address these uncertainties, experts increasingly recognize the need to monitor pest and disease outbreaks and have called for a global surveillance system to monitor these and improve responses.
Recent technological tools like the suitcase-sized mobile lab MARPLE, which tests pathogens such as wheat rust in near real-time and gives results within 48 hours, allow for early detection. Early warning systems are also crucial tools to warn farmers, researchers and policy makers of potential outbreaks.
Breeding pest- and disease-resistant varieties is another environmentally friendly solution, since it reduces the need for pesticides and fungicides. Collaborating with scientists worldwide, CIMMYT works on developing wheat and maize varieties resistant to diseases, including Fusarium Head Blight (FHB), wheat rust, wheat blast for wheat and maize lethal necrosis (MLN) for maize.
A ladybug (or ladybird) beetle sits on a wheat spike of an improved variety growing in the field in Islamabad, Pakistan. Photo credit: A. Yaqub/CIMMYT.
Beneficial insects can also act as a natural pest control for crops. Ladybugs, spiders and dragonflies act as natural predators for pests like aphids, caterpillars and stem borers. Other solutions include mechanical control measures such as light traps, pheromone traps and sticky traps, as well as farming practice controls such as crop rotation.
The United Nations has declared this year as the International Year of Plant Health, emphasizing the importance of raising global awareness on how “protecting plant health can help end hunger, reduce poverty, protect biodiversity and the environment, and boost economic development.”
As part of this initiative, CIMMYT will host the 24th Biannual International Plant Resistance to Insects (IPRI) conference from March 2-4. The conference will cover topics including plant-insect interactions, breeding for resistance, and phenotyping technologies for predicting pest resistant traits in plants.
Cover photo: A locust swarm in north-east Kenya. The UN Food and Agriculture Organization has warned that the swarms already seen in Somalia, Kenya and Ethiopia could range further afield. Photograph: Sven Torfinn/FAO
Any fifth grader is familiar with the Cretaceous-Tertiary mass extinction, which saw dinosaurs — and three quarters of all species alive at that time — disappear from Earth, probably after it was struck by a very large asteroid. However, few people are aware the planet is currently going through a similar event of an equally large magnitude: a recent report from the World Wide Fund for Nature highlighted a 60% decline in the populations of over 4,000 vertebrate species monitored globally since 1970. This time, the culprit is not an asteroid, but human beings. The biggest threat we represent to other species is also the way we meet one of our most fundamental needs: food production.
As a response, scientists, particularly ecologists, have looked for strategies to minimize trade-offs between agriculture and biodiversity. One such strategy is “land sparing,” also known as the “Borlaug effect.” It seeks to segregate production and conservation and to maximize yield on areas as small as possible, sparing land for nature. Another strategy is “land sharing” or “wildlife-friendly farming,” which seeks to integrate production and conservation in the same land units and make farming as benign as possible to biodiversity. It minimizes the use of external inputs and retains unfarmed patches on farmland.
A heated debate between proponents of land sparing and proponents of land sharing has taken place over the past 15 years. Most studies, however, have found land sparing to lead to better outcomes than land sharing, in a range of contexts. With collaborators from CIFOR, UBC and other organizations, I hypothesized that this belief was biased because researchers assessed farming through a narrow lens, only looking at calories or crop yield.
Many more people today suffer from hidden hunger, or lack of vitamins and minerals in their diets, than lack of calories. Several studies have found more diverse and nutritious diets consumed by people living in or near areas with greater tree cover as trees are a key component of biodiversity. However, most of these studies have not looked at mechanisms explaining this positive association.
Forests for food
Studying seven tropical landscapes in Bangladesh, Burkina Faso, Cameroon, Ethiopia, Indonesia, Nicaragua and Zambia, we found evidence that tree cover directly supports diets in four landscapes out of seven. This may be through the harvest of bushmeat, wild fruits, wild vegetables and other forest-sourced foods. The study further found evidence of an agroecological pathway — that forests and trees support diverse crop and livestock production through an array of ecosystem services, ultimately leading to improved diets — in five landscapes out of seven. These results clearly demonstrate that although land sparing may have the best outcomes for biodiversity, it would cut off rural households from forest products such as forest food, firewood and livestock feed. It would also cut off smallholder farms from ecosystem services provided by biodiversity, and smallholders in the tropics tend to depend more on ecosystem services than on external inputs.
In Ethiopia, previous research conducted by some of the same authors has demonstrated that multifunctional landscapes that do not qualify as land sparing nor as land sharing may host high biodiversity whilst being more productive than simpler landscapes. They are more sustainable and resilient, provide more diverse diets and produce cereals with higher nutritional content.
The debate on land sparing vs. sharing has largely remained confined to the circles of conservation ecologists and has seldom involved agricultural scientists. As a result, most studies on land sparing vs. sharing have focused on minimizing the negative impact of farming on biodiversity, instead of looking for the best compromises between agricultural production and biodiversity conservation.
To design landscapes that truly balance the needs of people and nature, it is urgent for agronomists, agricultural economists, rural sociologists and crop breeders to participate in the land sparing vs. sharing debate.
This study was made possible by funding from the UK’s Department for International Development (DFID), the United States Agency for International Development (USAID) through the project Agrarian Change in Tropical Landscapes, and by the CGIAR Research Programs on MAIZE and WHEAT.
“This event is a first of its kind. Here you have the fertilizer industry, which is relatively conservative, and yet there are speakers such as Mostafa Terrab of the OCP Group or Svein Tore Holsether of Yara who are pushing this future agenda,” said Bruce Campbell, Director of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).
“If I was from the fertilizer industry, I would really wake up, as perhaps is happening with some companies. If you look at the airlines industry, you see some super visionary players and others who are not. I feel that there could be players in this group who could be as visionary: looking at cutting down the energy inputs into fertilizer production, working together with governments to reform subsidies that promote over-fertilization, working towards precision fertilizer application. If the fertilizer industry wants to gain the trust of a more and more discerning public, then they need to show climate leadership,” Campbell remarked.
Early plant vigor can be improved through the use of direct seeders, which place fertilizer close to the seed. (Photo: Wasim Iftikar / CIMMYT)
The right time and place
Although fertilizer use revolutionized agriculture and allowed farmers to grow better crops on less land, plant nutrients are often vilified because of the negative environmental impact caused by their improper use.
For this reason, experts often speak of the 4R stewardship principles of fertilizer: right fertilizer source, at the right rate, at the right time, and in the right place.
“The industry needs solid science to back up agricultural technology solutions in the realms of both nutrient and water management. Regarding the right placement, right time and the right quantity of fertilizer, mechanization solutions — such as direct seeders, which place fertilizer close to the seed — can really increase nutrient use efficiency and improve plant early vigor. Together with a wide range of partners, CIMMYT has been using these across smallholder systems of Asia, Africa and Latin America,” highlighted Martin Kropff, Director General of the International Maize and Wheat Improvement Center (CIMMYT), during one of the panel discussions.
In order to scale up the most relevant scientific findings and extension efforts, the focus should be on using available fertilizers better. This goes hand in hand with better management of organic matter and soils. There is a human element too: farmers’ efficiency could be improved with better advice especially targeted at extension offices or service providers.
At the event, David Nabarro challenged the fertilizer industry to take the lead in reforming the broken food system. (Photo: Marta Millere/CIMMYT)
S for sustainability
In order to identify the missing link of sustainability, just a day before the launch of the forum, the International Fertilizer Association (IFA) created a new Scientific Panel on Responsible Plant Nutrition. This group of international experts will provide objective knowledge and assessments for the fertilizer industry and other stakeholders to develop a more responsible plant nutrition system.
Bruno Gérard, Director of CIMMYT’s Sustainable Intensification research program and a member of the panel, spoke about CIMMYT’s unique selling proposition. “CIMMYT has a significant research agenda and experience in better nutrient management in wheat- and maize-based systems. In regions such as South Asia, the challenge is to produce more or the same with less and better fertilizers through improved management practices. Instead in Sub-Saharan Africa, the focus is on giving better access and knowledge so that farmers can produce more with adequate fertilizer inputs.”
Being part of the panel will give CIMMYT the opportunity to better link up with the fertilizer industry and contribute to improved fertilizer use in term of profitability, yield stability and risk, accessibility but also — from an environmental perspective — minimize the footprint of fertilizer through better agronomic practices and management.
The High Level Forum on Plant Nutrition took place on November 18-20, 2019, in Versailles, France.
Hafiz Uddin, a farmer from Ulankhati, Tanpuna, Barisal, Bangladesh. He used seeder fertilizer drills to plant mung beans on one acre of land, which resulted in a better yield than planting manually. (Photo: Ranak Martin)
Over the last few decades, deteriorating soil fertility has been linked to decreasing agricultural yields in South Asia, a region marked by inequities in food and nutritional security.
As the demand for fertilizers grows, researchers are working with government and businesses to promote balanced nutrient management and the appropriate use of organic amendments among smallholder farmers. The Cereal Systems Initiative for South Asia (CSISA) has published a new policy brief outlining opportunities for innovation in the region.
Like all living organisms, crops need access to the right amount of nutrients for optimal growth. Plants get nutrients — like nitrogen, phosphorus, and potassium, in addition to other crucially important micronutrients — from soils and carbon, hydrogen, oxygen from the air and water. When existing soil nutrients are not sufficient to sustain good crop yields, additional nutrients must be added through fertilizers or manures, compost or crop residues. When this is not done, farmers effectively mine the soil of fertility, producing short-term gains, but undermining long-term sustainability.
Nutrient management involves using crop nutrients as efficiently as possible to improve productivity while reducing costs for farmers, and also protecting the environment by limiting greenhouse gas emissions and water quality contamination. The key behind nutrient management is appropriately balancing soil nutrient inputs — which can be enhanced when combined with appropriate soil organic matter management — with crop requirements. When the right quantities are applied at the right times, added nutrients help crops yields flourish. On the other hand, applying too little will limit yield and applying too much can harm the environment, while also compromising farmers’ ability to feed themselves or turn profits from the crops they grow.
Smallholder farmers in South Asia commonly practice poor nutrition management with a heavy reliance on nitrogenous fertilizer and a lack of balanced inputs and micronutrients. Declining soil fertility, improperly designed policy and nutrient management guidelines, and weak fertilizer marketing and distribution problems are among the reasons farmers fail to improve fertility on their farms. This is why it is imperative to support efforts to improve soil organic matter management and foster innovation in the fertilizer industry, and find innovative ways to target farmers, provide extension services and communicate messages on cost-effective and more sustainable strategies for matching high yields with appropriate nutrient management.
Cross-country learning reveals opportunities for improved nutrient management. The policy brief is based on outcomes from a cross-country dialogue facilitated by CSISA earlier this year in Kathmandu. The meeting saw researchers, government and business stakeholders from Bangladesh, India, Nepal, and Sri Lanka discuss challenges and opportunities to improving farmer knowledge and access to sufficient nutrients. Several key outcomes for policy makers and representatives of the agricultural development sector were identified during the workshop, and are included in the brief.
Extension services as an effective way to encourage a more balanced use of fertilizers among smallholder farmers. There is a need to build the capacity of extension to educate smallholders on a plant’s nutritional needs and proper fertilization. It also details how farmers’ needs assessments and human-centered design approaches need to be integrated while developing and delivering nutrient application recommendations and extension materials.
Nutrient subsidies must be reviewed to ensure they balance micro and macro-nutrients. Cross-country learning and evidence sharing on policies and subsidies to promote balanced nutrient application are discussed in the brief, as is the need to balance micro and macro-nutrient subsidies, in addition to the organization of subsidy programs in ways that assure farmers get access the right nutrients when and where they are needed the most. The brief also suggests additional research and evidence are needed to identify ways to assure that farmers’ behavior changes in response to subsidy programs.
Market, policy, and product innovations in the fertilizer industry must be encouraged. It describes the need for blended fertilizer products and programs to support them. A blend is made by mixing two or more fertilizer materials. For example, particles of nitrogen, phosphate and small amounts of secondary nutrients and micronutrients mixed together. Experience with blended products are uneven in the region, and markets for blends are nascent in Bangladesh and Nepal in particular. Cross-country technical support on how to develop blending factories and markets could be leveraged to accelerate blended fertilizer markets and to identify ways to ensure equitable access to these potentially beneficial products for smallholder farmers.
Kassim Massi and Joyce Makawa have learned how conservation agriculture nurtures the soil of their 2.5-acres farm in Lemu, Malawi, and helps them to better cope with regular dry spells and storm rains. With four children and two grandchildren, their livelihoods depend on rainfed crop farming, in particular maize, the main staple in Malawi, and a few goats and free-range poultry. The International Maize and Wheat Improvement Center (CIMMYT) introduced them to conservation agriculture, along with five other families in their community.
“I have learnt a lot from this experiment. I can see that with crop rotation, mulching and intercropping I get bigger and healthier maize cobs. The right maize spacing, one seed at the time planted in a row, creates a good canopy which preserves the soil moisture in addition to the mulch effect,” Massi explains. “The mulch also helps to limit water runoff when there are heavy rains. I don’t see the streams of mud flowing out of this plot like for my other field where I only planted maize as usual on ridges,” he adds.
Massi and Makawa started small, on a quarter acre, testing maize and maize-pigeon pea intercropping under conservation agriculture. Later they diversified to a maize-groundnut rotation with pigeon pea alleys, while introducing different drought-tolerant maize varieties on their plot. Pigeon pea and groundnut are legume crops that enrich the soil in nitrogen via nodules that host specific bacteria called rhizobia in their root systems. Massi and Makawa also put layers of maize stalks and groundnut haulms on the ground after harvest, creating a mulch that not only enriches the soil in organic matter but retains soil moisture and improves soil structure.
While they got only two bags of 50kg maize grain from their conventionally tilled maize field, they harvested almost three times more maize grain plus three bags of groundnuts, and two and half bags of pigeonpea from the 0.1 hectares grown under conservation agriculture. “This plot has become our food insurance and we plan to expand it.”
Family farmers Kassim Massi and Joyce Makawa in Lemu, Malawi. (Photo: Shiela Chikulo/CIMMYT)
Good for the soil and good for the farmer
“Building healthy soils over the years is one of the great impacts of conservation agriculture,” explains Christian Thierfelder, an agronomist with CIMMYT in Zimbabwe. “With no tillage, legume rotation or intercropping and crop residue management, a beneficial soil pore structure is developed over time. This enables water to infiltrate into the soil where it is available for plant growth in times of drought or during in-season dry spells.”
Under the GIZ-funded Out scaling climate-smart technologies to smallholder farmers in Malawi, Zambia & Zimbabwe initiative, the different ecosystem services that soils bring have been measured against the typical ploughed maize monocropping system. Fifteen year-long experiments show that 48.5mm more water infiltrates per hour under no-till as compared with the conventional method. Soil erosion is reduced by 64% for ripline-seeded maize with legume intercropping. At the Henderson Research station in Zimbabwe where soil erosion loss has been quantified, it means 90 metric tons per hectare of topsoil saved over twelve years.
“Conservation agriculture is good for the soil, and it is good for the farmer. The maize-legume intercropping under conservation agriculture provides very good financial return to labor and investment in most rural communities we worked with,” Thierfelder notes.
Climate mitigation or resilience?
There is growing recognition of the importance of soils in our quest for sustainability.
Soils play for instance an important role in climate regulation. Plants fix carbon dioxide (CO2) through photosynthesis and when those plants die and decompose, the living organisms of the soil, such as bacteria, fungi or earthworms, transform them into organic matter. That way, soils capture huge quantities of the carbon emissions that fuel climate change. This soil organic carbon is also essential for our food security because it retains water, and soil nutrients, essential for growing crops.
The quantity of carbon soils capture depends on the way farmers grow their crops. Conservation agriculture improves soil biodiversity and carbon sequestration by retaining crop residues as mulch, compared to conventional practices.
“Research shows that practices such as conservation agriculture can restore soil organic carbon at the level of four per thousand when farmers apply all principles of conservation agriculture: no-till, soil cover and crop diversification,” explains Marc Corbeels, agronomist seconded to CIMMYT from Cirad. Increasing soil organic content stocks globally by 0.4% per year is the objective of the “4 per 1000” initiative as a way to mitigate climate change and improve food security. At global level, sequestrating 0.4% more soil organic carbon annually combined with stopping deforestation would counteract the annual rise in atmospheric CO2.
“The overall soil organic carbon sequestration potential of conservation agriculture should however not be overestimated,” Corbeels warns. “Carbon sequestration is complex and context-specific. It depends for instance on the type of soils and the initial soil organic status, and the crop and biomass productivity as enough crop residues should be produced.”
“Now farmers in Malawi, Zambia and Zimbabwe are facing prolonged drought and, in some parts, farming communities got hit by flash floods. With degraded and barren soils in this tropical environment, it is a disaster. In my experience, more than mitigation, improved climate resilience is a bigger benefit of conservation agriculture for the farmers”, Corbeels says.
“Science is important to build up solid evidence of the benefits of a healthy soil and push forward much-needed policy interventions to incentivize soil conservation,” Thierfelder states.
Scaling out conservation agriculture practices is what has driven him over the past decade in southern Africa.
“One big lesson I learnt from my years of research with farmers is that if you treat well your soil, your soil will treat you well. Conservation agriculture adopters like Kassim Massi and his family are more resilient to these successive shocks. We need more farmers like them to achieve greater food security and climate resilience in the region,” he concludes.
December 5, we are celebrating World Soil Day under the theme “Stop Soil Erosion, Save our Future!” As CIMMYT’s research shows, farmers cannot deliver sustainable food security without healthy soils, as the farming land producing our staple crops provide important environmental services as well. CIMMYT calls for soil-smart agriculture and food systems.
Food entrepreneur Jorge Gaviria had the idea to small-scale farmers one by one who had surplus corn, buy it from them at market price and then import it to the United States. He partnered with CIMMYT to build up relationships with farmers, working out intricate systems that would determine fair prices and ensure that they were only buying surplus corn.
Researchers visit maize fields in Ethiopia’s Wondo Genet Agricultural Research Center. (Photo: Peter Lowe/CIMMYT)
One major reason why maize productivity in sub-Saharan Africa is very low is poor soil health. Soil acidity is often mentioned because of its impact on crop yields and the extent of acid soils in the region. A recent soil mapping exercise, conducted by the Ethiopian Soil Information System (EthioSIS) under the administration of the Ethiopian Agricultural Transformation Agency (ATA), estimated that 43% of arable lands were affected by acid soils and that 3.6 million people, about 10% of the total rural population, live in areas with acidic soils.
Very acid soils — those with a pH below 5.5, roughly one hundred times more acidic than neutral soils — are associated with certain toxicities, like aluminum and iron excess, and some nutrient deficiencies. Soil acidity pushes soil nutrients out of reach of the plant, leading to stunting of root system and plant. As a result, the plant becomes also less tolerant to drought.
Soil acidification depends on soil nature, agroecology and farming systems. It happens through natural leaching of CO2 after rainfall and excess application of nitrogenous fertilizer or organic matter, for instance.
As a result, soil acidity significantly affects maize yields. In Ethiopia, studies have revealed substantial impacts on crop productivity related to acid soils and the importance of acid soil management for Ethiopia’s food security. The Ethiopian Institute of Agricultural Research (EIAR) estimated that soil acidity on wheat production alone costed the country over 9 billion Ethiopian Birr, about $300 million per year.
Acidic soils in the limelight
Preliminary analysis led by the International Food Policy Research Institute (IFPRI) suggests that yields of major cereal crops, such as wheat and barley, could increase by 20 to 40% with the application of lime in acidic areas of the country.
While these preliminary results are significant, we need to know more about local farmers’ experience with acidic soil and their mitigation strategies. Such impact assessments are however typically determined at either the national or experimental plot level and do not map where mitigating against acid soils would be the most profitable.
To improve acid soils, farmers may apply lime on their fields to raise the pH, a practice known as liming. How much lime to apply will depend on the crop, soil type but also on the quality of lime available. Liming has multiple beneficial effects like improving nitrogen fixation of legume nodules, boosting yields of legume crops.
But liming has a cost. It can quickly become a very bulky affair as we need to apply 3 to 4 tons per hectare for sandy soils and up to 8 tons per hectare for clay and humifere soils.
Furthermore, existing lime markets are quite limited or even non-existent in many areas, even those where acidic soils are prevalent. Developing supply chains from scratch is difficult and costly. Understanding the costs and potential returns to such investments is important. There are many questions to ask at different levels, from the farm and farming system to the lime supply chain. What are the available lime sources — calcitic, dolomite or blend — and lime quality? Where are the lime processing units and how could you assess the transport cost to the farms? What could be the crop yield response depending on the lime application?
User-friendly and scalable dashboard
IFPRI, in collaboration with EIAR, the International Maize and Wheat Improvement Center (CIMMYT) and the German aid agency GIZ, developed a pilot in Ethiopia’s Amhara region to help better target lime interventions for a greater impact. Amhara region was chosen because of the importance of acid soils, and access to extensive soil data.
Combination of several spatial datasets on soil quality, agroecological, weather, long-term agronomic trials and crop modelling tools enabled to generate at scale, georeferenced estimates of crop yield responses for different lime applications. Calibration of this spatial model for wheat estimated a yield increase of approximately 30% increasing the pH from 5.5 to 6.5, which is relatively consistent with general research data and expert opinion.
Mapped estimates of the grain prices and the delivered costs of lime, based on the location of the lime crushers in the region and transport costs, enables then to map out the spatial profitability of lime operations.
Initial calculations revealed a great variability of lime costs at the farmgate, with transportation representing at least half of total lime costs. It showed also that farmers often do not use the most cost-effective combination of inputs to tackle soil acidity.
Another possible application is to determine maize growing areas where lime benefits outweigh the costs, which would be ideal sites for demonstrating to farmers the positive impact lime applications could have to their livelihoods.
This Amhara lime dashboard prototype demonstrated its scalability. A national dashboard is currently being developed, which includes lime sources GPS location, grain prices and district-level soil quality mapping. This approach is tested also in Tanzania.
CIMMYT and its partners plan to package such tool in a user-friendly open-access web version that can be rapidly updated and customized depending on the area of intervention, for instance integrating a new lime source, and applied for different crops, and across the Eastern African region. Such dashboards will help development organizations and government make better informed decisions regarding lime investments.
Step into supermarkets or restaurants in Mexico City and surrounding towns and you might see products made from blue maize — food which would not have been available just a few years ago. Some of Mexico’s favorite dishes are taking on a new hue with blue corn chips, blue tortillas or blue tamales. But should breeders, millers, processors and farmer organizations invest in expanding the production of blue maize and blue maize products? Are consumers really interested, and are they willing to pay more?
These are some of the questions researchers at the International Maize and Wheat Improvement Center (CIMMYT) in Mexico set out to answer. They set up study to test consumer preferences and willingness to pay for this blue maize tortillas.
Maize is a main staple crop in Mexico and tortillas form the base of many traditional dishes. Blue maize varieties have existed for thousands of years, but until recently they were mostly unknown outside of the farming communities that grew them. In addition to its striking color, the grain has gained popularity partly due to its health benefits derived from anthocyanin, the blue pigment which contains antioxidants.
Trent Blare (left), economist at CIMMYT and leader of the study, conducts a choice experiment with interviewee Luis Alcantara. (Photo: Carolyn Cowan/CIMMYT)
“Demand for blue maize has skyrocketed in the past few years,” said Trent Blare, economist at CIMMYT and the leader of the research.” Three years ago, white and blue maize sold at the same price. One year ago, blue maize cost just a few Mexican pesos more, and now blue maize is worth significantly more. However, we still lack information on consumer demand and preferences.”
According to Blare, the end goal of the study is to explore the demand for blue maize and try to better understand its market potential. “If we want farmers who grow blue maize to be able to get better market value, we have to know what the market looks like.”
This research received funding from Mexico’s Agency for Commercialization Services and Agricultural Market Development (ASERCA), which has been working with farmer organizations on post-harvest storage solutions for their maize. As blue maize is softer than typical white or yellow varieties, it requires special storage to protect it against insects and damage. In order to help provide farmers with the correct maize storage technology, ASERCA and others in Mexico will benefit from a deeper understanding of the market for blue maize in the region. In addition, researchers were interested to know if there is a premium for growing blue maize, or for making tortillas by hand. Premiums could help convince farmers to invest in post-harvest technologies and in the production of blue maize.
“There is this idea that demand should come from producers, but there are many steps along the maize value chain. We’re basically going backwards in the value chain: is there demand, is there a market, going all the way from the consumer back to the farmer,” Blare explained.
“There was an interesting gender aspect to this research: it was mostly women buying and making these maize-based foods, and women were more willing to pay a premium for blue maize,” said Miriam Perez (right), research assistant and interviewer. (Photo: Carolyn Cowan/CIMMYT)
A matter of taste
The study was conducted in Texcoco, just outside of Mexico City, where CIMMYT’s global headquarters are based. This town in the State of Mexico was chosen because of its long history growing and consuming blue maize. Interviews were held in three different locations, a local traditional market and two local shopping malls, in order to ensure that different socioeconomic groups were included.
“There is a certain pride in the blue tortilla. As Mexicans, the tortilla is something that brings us together,” said Mariana Garcia Medina, research assistant and interviewer. (Photo: Carolyn Cowan)
The team interviewed 640 consumers, asking questions such as where do they buy different types of tortillas, in which dishes they use different types of tortillas and if they faced difficulties in purchasing their preferred tortilla. The team also conducted sensory analysis and attributes, and gave study participants a choice between handmade blue maize tortillas, handmade white maize tortillas, and machine-made white maize tortillas.
The interviewees were given three different scenarios. Would they be willing to pay more for blue tortillas compared to other tortillas if eating quesadillas at a restaurant? To serve during a special event or visit from a family member? For everyday use?
The answers allowed researchers to quantify how much more consumers were willing to pay and in what circumstance, as they were given different price points for different types of tortillas in different scenarios.
True colors
The researchers found that preferences for blue and white maize were distinct for different dishes, and that there was a particular preference for blue maize when used in traditional dishes from this region, such as tlacoyos or barbacoa. A majority of consumers was willing to pay more for higher quality tortillas regardless of the color, as long as they were made handmade and fresh from locally grown maize. Interviewers also saw a noticeable difference in preference for blue tortillas depending on the situation: blue tortillas are demanded more for special occasions and in traditional markets.
“I found it fascinating that there is a difference in blue maize consumption based on the circumstance in which you are eating it.” Blare said. “This is one of the innovations in our demand study — not analyzing the demand for a food product in general but analyzing differences in demand for a product in different contexts, which is important as food is such an important component for celebrations.”
“We think there is potential to replicate this in other places in Mexico, to see consumer preference and price willingness for blue maize and other value-added maize products,” said Jason Donovan, senior economist at CIMMYT. “This will not just inform farmers and markets but also how to do this kind of research, especially in middle-income economies. This study is the first of its kind.”
“As a Colombian, it really surprised me that Mexicans were able to distinguish between white and blue maize tortillas even when blindfolded! It really shows the importance of maize to their diet and culture,” said Diana Ospina Rojas (left), research assistant and interviewer. (Photo: Carolyn Cowan/CIMMYT)
Still got the blue
Overall, the results revealed that women were willing to pay 33% more for blue maize tortillas while men were willing to pay 19% more. For every additional year of education, a consumer was willing to pay 1% more for blue maize tortillas. Interestingly, a person’s income had no effect on her or his willingness to pay for more blue maize tortillas. Many people interviewed expressed a preference for blue maize, but commented that they cannot always find it in local markets.
The information collected in these choice experiments will help farmers, breeders, and other actors along the maize value chain make more informed decisions on how to best provide blue maize varieties to the public — and give consumers what they want.
“It was a very interesting experience, I’ve never participated in a survey like this before and I think it is important to take the time to think about our decisions about food,” said Brenda Lopez, one of the interviewees in the choice experiment. Lopez preferred the handmade tortillas, especially those made with blue maize. “I think they have more flavor,” she said. “I just bought handmade tortillas in the market before participating in this survey, but I had to buy white because there was no blue available.”
Another interviewee, Luis Alcantara, agreed. “I prefer blue because of the flavor, the texture, even the smell,” he said. “At home we eat machine-made tortillas because it is hard to find handmade tortillas, and even if you do, they are not blue. We would buy blue if we could.”
Cover photo: Blue maize tortillas (Photo: Luis Figueroa)
CIMMYT colleagues pose for a photo at the 23rd Latin American Maize Reunion. (Photo: Carlos Alfonso Cortes Arredondo/CIMMYT.)
Latin America is the birthplace of maize and home to much of its genetic diversity. Maize is a main staple food across the continent and plays an important role in local culture and gastronomy. However, maize faces many challenges, from climate change related stresses such as drought and heat to emerging pests and diseases. Maize experts, as well as scientists from other key crops, from around the world came together to discuss these challenges and how to solve them at the 23rd Latin American Maize Reunion and 4th Seed Congress, held October 7-10 in Monteria, Colombia.
The reunion began with a welcome address from Luis Narro, a senior maize scientist with the International Maize and Wheat Improvement Center (CIMMYT). Narro thanked participants for coming from throughout the region and discussed the history of the event. “Why are we here today? Because maize is one of the most important crops of this century. This should be both a challenge and incentive for us to continue our work with maize, as it is a crop with huge demand,” he said.
In the inaugural session, Deyanira Barrero, general manager of the Colombian Agricultural Institute (ICA) and Jorge E. Bedoya, president of the Society of Colombian Farmers, highlighted the importance of seeds and strategies to ensure the quality and future of Colombia and Latin America’s agri-food systems.
The event was organized by the Colombian Corporation for Agricultural Research (Agrosavia), the Colombian Seed and Biotechnology Association (Acosemillas), the National Federation of Cereal and Legume Growers (Fenalce), the Latin American maize network, and the International Maize and Wheat Improvement Center (CIMMYT). Four CIMMYT scientists presented at the reunion, sharing their experience with and perspectives on agronomy, seed systems, native maize and strategies to increase resilience to climate change.
Nele Verhulst, senior scientist at CIMMYT, presented on the development of management practices for conservation agriculture as well as post-harvest technologies in Latin America, particularly Mexico and Central America. She emphasized the importance of crop management in maize so that improved seeds can reach their maximum potential in terms of yield and profitability. The seed systems lead for Africa and Latin America with CIMMYT’s Global Maize Program, Arturo Silva, shared his experience in these regions strengthening maize seed systems and working to accelerate variety replacement with newer, better seeds. Terry Molnar, maize breeder at the Center, studies native maize varieties to identify characteristics such as disease resistance that can be used to develop improved maize varieties for smallholder farmers. Kai Sonder, head of CIMMYT’s Geographic Information System (GIS) unit, presented on the potential impact of climate change on global and regional maize production.
The reunion closed with the award session for the winners of the MAIZE Youth Innovators Awards 2019 – Latin America. The awards, an initiative of the CGIAR Research Program on Maize (MAIZE), seek to recognize the contributions of young women and men who are implementing innovations in Latin American maize-based agri-food systems.
Winners of the MAIZE Youth Innovators Awards 2019 – Latin America pose for a photo with their awards. (Photo: Carlos Alfonso Cortes Arredondo/CIMMYT.)
Eduardo Cruz Rojo, Mexico, won in the “Farmer” category for his work using biological control agents to protect maize from fall armyworm. Carlos Barragán and José Esteban Sotelo Mariche, both from Mexico, won in the category of “Change Agent” for their work helping farmers increase their maize yields through inter-cropping and for helping farmers better commercialize their native maize, respectively. In the “Researcher” category, Yésica Chazarreta, from Argentina, won for her research on the effect of maize planting dates on grain filling and drying. Omar Garcilazo Rahme of Mexico was recognized for his work helping farmers grow high-value edible maize fungus in traditional maize production systems. Viviana López Ramírez of Colombia won for her work on bacteriosis in maize, and Lucio Reinoso of Argentina for his contribution to the development of a maize seeder that helps farmers adopt conservation agriculture techniques. In a video message, B.M. Prasanna, director of the CIMMYT global maize program and the CGIAR Research Program on Maize (MAIZE), congratulated the young winners and expressed his hopes that they would inspire other young people to get involved in maize based systems. This was the first time the awards were held in Latin America, following Asia in 2018 and Africa in spring of 2019.
Two additional awards were given at the close of the reunion, one to Alberto Chassiagne, maize seeds systems specialist for Latin America at CIMMYT, who received first place in the scientific poster competition at the reunion for his work “Proposed model to generate seed production technology for maize hybrids”. Another award went to Luis Narro for his contributions to maize in Latin America throughout his career.
The conference was followed by a field day held October 10 at the Agrosavia Turipaná Research Center in Cereté, Colombia. The field day began with a speech by Colombia’s Minister of Agriculture and Rural Development, Andrés Valencia, who discussed the importance of agriculture to his country’s economy as well as plans to increase maize production to decrease reliance on imports. This announcement follows the launch of Maize for Colombia, a strategic plan to help improve maize production in the country while increasing sustainability.
A multi-crop, multi-use zero-tillage seeder at work on a conservation agriculture trial plot, left, at CIMMYT’s headquarters in Texcoco, Mexico. The residues retained on the soil surface and the permanent raised beds are in clear contrast with the conventional plot on the right. (Photo: CIMMYT)
New research by an international team of scientists, including International Maize and Wheat Improvement Center (CIMMYT) Director for the Integrated Development Program, Bram Govaerts, outlines a proposed accounting system for organic carbon in soils that could encourage farmers to adopt better land management practices and increase levels of organic carbon in their soil.
Reported this month in the journal Carbon Management, the study highlights how increasing soil organic carbon (SOC) would build agricultural resilience and fertility and reduce greenhouse gas emissions — but we need to be able to measure it.
Soil is a huge carbon reservoir — in fact, soils contain one of the largest organic carbon stocks on the planet. With proper land management, soils have the potential to store even more. Improved SOC levels have also been connected with improved soil quality, reduced susceptibility to erosion and greater agricultural yields and yield stability, particularly under drought. This makes them a crucial player in climate change mitigation and agricultural resilience.
Policy makers and environmental groups are becoming increasingly interested in soil health and its effect on climate change. The 4 per 1000 initiative, launched at the COP 21 climate talks in Paris in 2015, argues that an annual growth rate of 0.4% in soil carbon stocks would significantly reduce human activity-related CO2 concentrations in the atmosphere. The most recent Intergovernmental Panel on Climate Change (IPCC) assessment highlights carbon sequestration as one of the options, alongside massive fossil fuel reduction, to keep warming below 2 degrees Celsius, in accordance with the Paris Climate Agreement.
Increasing organic carbon content in soils also has another very important function: crop nutrition. Last year, researchers from CIMMYT and the Nature Conservancy found that wheat grown on soils rich in organic matter had more essential nutrients like zinc and protein.
However, increasing levels of organic carbon in the soil can be costly in the short term, so farmers need to see improvements in the performance of their soils as a result of their efforts.
Quantifying soil carbon
That’s where a global soil information system comes in. By integrating empirical models, expanded measurement and monitoring networks, remote sensing and crowdsourced management data, SOC stocks can be assessed efficiently and reliably. Farmers and policy makers would get a clear picture of how much soil organic carbon is increasing and at what rate.
The global soil information system would work by pulling different sources of existing information together to provide a comprehensive account of soil organic carbon stocks worldwide.
As SOC content can vary over time, an important component of the system would involve using monitoring networks at precise locations which can then be resampled regularly. Alongside this information, empirical models would be used to predict SOC changes based on already observed results from lab- and field-based experiments, and to predict the impacts of different soil and climate conditions. Remote sensing data can provide information on land cover, crop species and land management practices at a very low cost, to supplement and verify management activity data reported by land users.
The international team of scientists pointed out that greater coordination and transparency among scientists, remote sensing specialists and land managers is crucial to the success of a global soil information system.
Incentivizing carbon sequestration among land managers is no mean task. The authors argue that existing approaches like direct compensation to farmers for CO2 removal and storage, government subsidies such as the European Union’s Common Agricultural Policy (CAP) and the option of earning a premium price for producing sustainable agricultural products, need a reliable carbon accounting system to ensure their success. A global soil information system might just hold the key.
This study was made possible through the support provided by the TomKat Foundation. Additional support was provided by the NASA Harvest Consortium (www.nasaharvest.org), a multi-disciplinary program that empowers informed agricultural decisions through the use of Earth observations.
Staff members of CIMMYT and other CGIAR centers in Ethiopia participated in the country’s nationwide campaign that resulted in the planting of more than 350 million trees in one single day. (Photo: CIMMYT)
July 29, 2019, was a remarkable day for Ethiopia. People across the country planted 353,633,660 tree seedlings in just 12 hours, according to the official count, in what is believed to be a world record. This figure also exceeded the target of a nationwide campaign calling citizens to plant 200 million trees in one day. This initiative was part of the Ethiopian government’s “Green Legacy” initiative, which aims to plant 4 billion trees by October.
The International Maize and Wheat Improvement Center (CIMMYT) and other CGIAR centers working in Ethiopia joined the tree-planting campaign. In the morning of July 29, staff members turned out at Adwa park, near Addis Ababa’s Bole International Airport, to plant tree seedlings. This activity was coordinated by the International Livestock Research Institute (ILRI) after receiving an invitation from the Bole subcity administration.
Ethiopia’s tree-planting day received worldwide attention. Al Jazeera reported that, “in addition to ordinary Ethiopians, various international organizations and the business community have joined the tree planting spree which aims to overtake India’s 66 million planting record set in 2017.”
CIMMYT and CGIAR staff members put their tree seedlings in the ground. (Photo: CIMMYT)
A greener future for CGIAR
Ethiopia’s reforestation efforts align with CGIAR’s sustainability strategy.
In its current business plan, CGIAR has five global challenges including planetary boundaries. Food systems are driving the unsustainable use of the planet’s increasingly fragile ecosystem. A stable climate, water, land, forests and the biodiversity they contain are a precious, yet finite, natural resource. Food systems account for about one-third of greenhouse gas emissions and will be profoundly affected by its impacts. Agriculture is driving the loss of the world’s forests and productive land, with 5 million hectares of forests lost every year and a third of the world’s land already classified as degraded. Agriculture accounts for about 70% of water withdrawals globally, is a major cause of water stress in countries where more than 2 billion people live, and water pollution from agricultural systems poses a serious threat to the world’s water systems.
With Ethiopia’s increasing population, there is a high pressure on farmland, unsustainable use of natural resources and deforestation.
At the Agriculture Research for Development Knowledge Share Fair organized in Addis Ababa on May 15, 2019, CGIAR centers demonstrated how they are working together to improve agriculture production and environmental sustainability, tackling local challenges and generating global impact in partnership with other organizations, communities and governments.
At the fair’s opening ceremony, Seleshi Bekele, Ethiopia’s Minister of Water, Irrigation and Electricity, noted that the country has policies, institutional arrangements as well as human and financial resources to work towards sustainability. As a result, Ethiopia has made remarkable achievements towards meeting the Sustainable Development Goals with the continued support and contributions from partners like CGIAR. He also called CGIAR centers to support the efforts to plant 4 billion tree seedlings in 2019, as part of Ethiopia’s climate change adaptation and mitigation goals.
CIMMYT staff show their hands full of dirt after planting tree seedlings in Bole subcity, near Addis Ababa’s international airport. (Photo: CIMMYT)
Northwestern India is home to millions of smallholder farmers making it a breadbasket for grain staples. Since giving birth to the Green Revolution it has continued to increase its food production through rice and wheat farming providing food security to the region.
This high production has not come without shortfalls; groundwater tables are falling from excessive irrigation and climate change has brought erratic rainfall. In response, the state governments of Haryana and Punjab introduced separate legislation forcing farmers to delay rice planting to coincide with the arrival of the monsoonal rains in late June.
With rice sowing pushed back to tackle a looming water crisis, the time available between harvesting rice and planting wheat has been reduced. Consequently, the majority of farmers opt to burn the post-harvest rice straw to quickly prepare their fields for wheat. The majority of the 34 tons of rice residues the region produces is burned in a short window of time, throwing a lot of toxic smoke into the air.
New research, by the International Maize and Wheat Improvement Center (CIMMYT), delved into linkages between groundwater and agricultural burning policies. The study uncovered that groundwater conservation policies in Haryana and Punjab are exacerbating the nation’s air pollution crisis by concentrating crop residue burning in the late fall.
“Despite being illegal, the burning of post-harvest rice residues continues to be the most common practice of crop residue management, and while groundwater policies are helping arrest water depletion, they also appear to be exacerbating one of the most acute public health problems confronting India – air pollution,” said CIMMYT scientist and author of the study, Balwinder Singh.
Millions of farmers burn the straw that remains after the rice harvest to prepare their fields for a wheat crop. (Photo: Dakshinamurthy Vedachalam/CIMMYT)
Getting to the guts of air pollution’s chokehold on India
Air pollution in India has increased significantly since 2000. Each fall, from late October to November, a toxic fog containing a mixture of dust, carbon and particles covers northwestern India. For the 18.6 million who live in New Delhi the smog not only brings daily life to a standstill but slices years off life expectancy. It kills an estimated 1.5 million people every year, with nearly half of these deaths occurring in the Indo-Gangetic Plains, the northernmost part of the country that includes New Delhi.
The analysis suggests that temporal changes in burning are a prime contributor to the air quality crisis. The limited amount of time to prepare fields for wheat planting has caused fire intensity to increase by 39 percent, peaking in November with a maximum of 681 fires per day. This increase occurs when temperatures in New Delhi are lower and winds are weak. The still conditions trap pollution and limit the amount that can escape.
Recognizing policy tradeoffs is important for sustainable agricultural intensification
Agriculture for development researchers with CIMMYT investigate how best to sustainably intensify food production. This seeks to produce more food, improve nutrition and livelihoods, and boost rural incomes without an increase in inputs – such as land and water – while reducing environmental impacts. Policies can help to shape efforts towards sustainable intensification by encouraging farming practices that save resources and protect the environment. However, it is important that governments strike the right balance between food security, resource depletion and environmental quality.
The research results shed light on the sustainability challenges confronting many highly productive agricultural systems, where addressing one problem can exacerbate others, said Andrew McDonald, a professor at Cornell University and co-author of the study.
“Identifying and managing tradeoffs and capitalizing on synergies between crop productivity, resource conservation, and environmental quality is essential,” he said.
Policies to promote sustainable intensification can also burst India’s pollution bubble
Surface crop residue retention and incorporation are the promising on-farm management options to address the issue of burning as well as maintaining soil health and long-term sustainability, said M.L. Jat, a scientist with CIMMYT who coordinates sustainable intensification programs in northwestern India.
Apart from pumping toxic smoke into the air, ash left on fields after residue burning can negatively affect soil health in the long term. However, if residue is mulched into the soil, nutrient levels improve and carbon sequestration capacity increases, lowering the release of greenhouse gases. Additionally, residue retention reduces evaporation and increases soil moisture by as much as 10 percent during the wheat-growing season.
“A sensible approach for overcoming tradeoffs will embrace agronomic technologies such as the Happy Seeder, a seed drill that plants seeds without impacting crop residue, providing farmers the technical means to avoid residue burning,” he explained.
“When rice is ready to be reaped, a tractor or a harvester collects the grain, a spreader distributes the straw that remains on the ground and the Happy Seeder drills into the land to seed wheat,” Jat said. “Farmers no longer need to till the land to plant their wheat, instead they practice a form of conservation agriculture.”
M. L. Jat, CIMMYT Cropping Systems Agronomist with a no-till planter that facilitates no-burn farming. (Photo: Dakshinamurthy Vedachalam/CIMMYT)
Researchers at CIMMYT and Punjab Agricultural University have undertaken extensive trials in farmer fields and the new technology has proven itself as a step forward for developing viable solution to rice crop residue burning.
The Indian government launched a $157 million initiative to discourage burning through agricultural machinery innovations. However, the Happy Seeder is yet to be adopted widely. It is estimated that to cover 50 percent, 5 million ha, of the total acreage under rice-wheat cropping systems in India, about 60,000 Happy Seeders are needed. At present, there are only about 10,000 available.
A recent policy brief suggests rapid adoption needs a major government push to publicize and popularize the technology. The brief suggests delivery of machinery hire services through Primary Agriculture Cooperative Societies and private entrepreneurs with ongoing government support is a viable tool to equitably reach farmers.
Climate mitigation or resilience? 
“Science is important to build up solid evidence of the benefits of a healthy soil and push forward much-needed policy interventions to incentivize soil conservation,” Thierfelder states.
