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It may be surprising to see agriculture being held responsible for many of the perils that mankind has brought upon itself and the planet. The editors’ aim is to reassess and reimagine the food sys...

The High Plains have been pillaged by a society of wreckers. Finding abundance, they slaughtered bison by the millions to exterminate the Plains Indians; they ploughed the sod and created the Dust ...

What Dr Samuel Johnson did for English, Professor Amir Kassam has done for Conservation Agriculture (CA). He is eminently well qualified and has enlisted more than a hundred battle-hardened champio...

To qualify for payments from the public purse, farmers will not only have to produce food but, also, demonstrate good stewardship by delivering public goods: arresting soil erosion, abating floods,...

Agriculture across the Steppes faces many challenges. No-till is a promising option for transition to more sustainable farming systems. However, simple replacement of the plough by a ploughless system does not cut the Gordian knot of problems related to crop productivity and soil fertility. Extending Conservation Agriculture requires an holistic approach to farm management oriented towards regenerating soil health that simultaneously cuts the need for soil tillage, synthetic fertilizers, and chemical control of weeds, pests and diseases. Observance of crop rotation is mandatory for adoption of no-till, together with other measures for building soil fertility. Zero tillage of winter cereals after late-harvested predecessors doubles the accumulation of soil moisture during the autumn–winter-spring period relative to conventionally cultivated, early-harvested predecessors, not to mention black fallow.

Soil maps in Ukraine need to be updated as a matter of urgency. They are now more than 30 years old, many are 60 years old. The original mapping was undertaken for other purposes than today’s, and the soils have changed. Apart from all this, systematic errors have been introduced by digitization, geodesic rectification and the attribution of soil characteristics from the original mapping. Legal issues now arise at the point of sale of land on the basis of doubtful data, for instance with legalization of forecast agro-production groups or soils. This is neither fair nor reasonable. Prior to some future programme of large-scale soil survey, these problems may be avoided by deleting doubtful data and substituting the standard rental income of the corresponding agricultural and non-agricultural areas.

Soil is the biggest brake on global heating. It holds more carbon than the atmosphere and all standing vegetation put together. But farmers have been burning off soil organic matter for 12 thousand years; the last thirty-five years of satellite measurements of carbon-capture capacity reveal a dramatic decline across the steppes; the best soil in the world is the worst example of land degradation. Long-term field experiments show that, since 1970, soil carbon has been run down by 165-192 tC/ha; taking the least of these figures, mineralization of soil carbon has emitted 25 ppm of atmospheric CO2 over this period. To turn this situation around: stop ploughing; don't fallow; plant windbreaks; adopt a diverse cropping system; and integrate crops and livestock-alternatively, convert the biomass to biogas. In Ukraine, this plan, with one year in three under perennial legumes and grasses, would transform the annual loss of 3.4-4 tC/ha to annual carbon capture of 0.5-1.5 tC/ha/yr, save half the cost of diesel fuel and increase production. At the same time, the legumes will produce all the nitrogen the crops can use-with enormous savings in the energy presently used to manufacture nitrogen fertilizer. Integration of crops with livestock would transform the rural economy and the green biomass, converted to biogas, could replace the country's coal-fired power stations.

To qualify for payments from the public purse, farmers must not only grow food but demonstrate good stewardship by delivering public goods: arresting soil erosion, abating floods, recharging groundwater, mitigating global heating… Moreover, discerning consumers seek guarantees that their food is grown sustainably which are not provided by prices and labelling. The proposed Standard for Soil Health meets these needs by matching the condition of the soil with its capacity to grow crops and deliver environmental services. The criteria are ground cover, biological status represented by soil organic matter, and physical status represented by bulk density. These yardsticks also reveal trends, so credit may be given for good management as well as for inherent soil quality.

Farmers are responsible for one-third of greenhouse gas emissions and there is no plan to deal with this; their impact on land and water resources, floods, droughts, and the global extinction of species also cries out for attention. Half of the humus that makes the Black Earth what it is has been pumped into the air and, with it, the soil’s capacity to receive rainfall, supply water to crops, and recharge streams and groundwater is diminished. Since 1970, soil carbon across the steppes has been run down by 2.4–3.8/tC/ha/yr (5 times more where the soil has been eroded). Taking the least of these figures, mineralization of soil organic carbon (SOC) has emitted 195 Gt or 25 ppm of atmospheric CO2. Adoption of Conservation Agriculture that includes a diverse crop rotation with perennial legumes and grasses offers carbon capture of 0.5–1 Gt/yr, arrest of soil erosion, and bigger crops. At present, there is no market for the perennial grasses and legumes needed to put the organic matter back into the soil. The old-fashioned answer is to integrate crops and livestock – farmyard manure doubles the benefit of crop rotation, integrating crops and livestock will regenerate rural communities, and the extra production will make space to restore degraded land for wildlife, water resources, and amenity. But the people and skills needed for livestock enterprises are now hard to come by. Alternatively, the green biomass can be converted to biogas: a ready market for all the green biomass that can be grown would transform farming systems. This would be a strategic investment that can easily be funded through Green Bonds.

Affordable food is a political imperative. There is nothing more expensive: the food system delivers cheap food, but it takes no account of the damage done along the way. It operates in three modes. In Mode 1, farmers manage land and water to produce crops and livestock. Incidentally, they manage the landscape and carbon capture from the atmosphere by crops and its conversion to soil organic matter. Soil organic matter matters: it fuels the world of the soil that breaks down wastes and toxins, regenerates crop nutrients and controls pests and diseases; it maintains soil structure that enables infiltration and storage of rainfall; and it holds more carbon than the atmosphere and all standing vegetation put together. If these services are considered at all, they’re taken for granted. Nowadays, Mode 1 accounts for only one-tenth of the value added in the food system; farm-gate prices have been driven down relentlessly so farms have had to get bigger or get out. Production certainly benefits from economies of scale and the gifts of technology: ever-more-powerful machines, new crop varieties, fertilisers, pesticides, irrigation—but these gifts exact a cost by exposing topsoil to the elements, turning it upside down with every pass of the plough and raiding soil organic matter. So, more power and more chemicals are needed; soil erosion, floods and droughts are exacerbated; groundwater isn’t recharged; and agriculture burns up more energy than it harvests. None of this is accounted in the cost of food but, over millennia, agriculture has amassed rights and vested interests that have resisted reforms that could take these costs into account. In the second mode, food is traded, processed and retailed; these activities now account for most of the value added in the food system. Comprehensive legal foundations and accounting rules that have been impossible to install in primary production have proven politically feasible in trade, processing and retail. In the third mode, food consumption, public policy again overrides the market to enable poor people to get food that is still too costly for them. The system is unsustainable—ecologically, environmentally and economically. It will only be sustainable economically if the power relations across the food system can be redressed; if consumers paid the costs of maintaining environmental services, farmers in a viable commercial system might be able to remedy some of the ecological ills.

Between 1950 and 1980, most of the actual and potential agricultural land in the tropics was covered by surveys of natural resources: soils, climate and vegetation – an astounding achievement by ra...

Objective Persons who have experienced homelessness and are living in permanent supportive housing experience high rates of health and mental health problems. Given that physical activity is associated with improved health outcomes and persons with homelessness histories report high rates of cell phone use, phone-based interventions to increase physical activity may be effective for improving health and wellbeing among persons in permanent supportive housing. Methods To understand the acceptability and feasibility of a cell phone-based physical activity intervention in this population, this 6-week pilot study enrolled 13 persons living in permanent supportive housing. Participants were eligible if they had completed their final, 12-month follow-up interview in a larger, longitudinal study of persons moving into permanent supportive housing in the Los Angeles area, spoke English, and reported comorbid chronic physical and mental health conditions. For the study duration, participants wore a pedometer, received multiple weekly motivational text messages on set days (at times selected by the participant), and responded via text to weekly depression screeners and requests to report their weekly step totals, as recorded by their pedometers. Follow-up interviews asked open-ended questions about study participation and satisfaction. Results Participants were 53 years old on average, most were female (54%), and most were African-American (62%). Changes to people’s physical activity levels were limited, but participants reported increased quality of life during the intervention period. Interviews revealed that the intervention was well received and enjoyable for participants. Conclusions The efficacy of utilizing cell phones to improve health and wellbeing among adults living in permanent supportive housing requires further research, but these pilot findings suggest that such interventions are feasible and acceptable.

The political imperative of cheap food has driven down farm gate prices, driven up the size of farms, and incited industrialized farming. The boost to production between the 1960s and 1980s rested partly on plant breeding but, equally, on cheap energy and its derivatives including nitrogen fertilizers and pesticides, and expansion of irrigation. But the system is unsustainable: unseen costs include mining of soil organic matter, greenhouse gas emissions, and the hollowing out of rural communities. Soil regeneration is an essential starting point in the necessary transition to sustainability. Comparative analysis of soil organic carbon in Chernozem under grassland and arable across Russia, Ukraine, Kazakhstan and Moldova reveals great opportunities for cutting CO2 emissions, sequestering carbon, and increasing crop production. Since 1963, conventional farming systems have run down soil organic carbon by 2.4–3.8/tC/ha/yr; the CO2 emissions amount to some 77 Gt or 10 ppm of atmospheric CO2. Current emissions can be halved just by adopting conservative crop rotations and eschewing black fallow. Conservation Agriculture embracing crop rotations that include perennial grasses and legumes, no black fallow, and zero tillage, may achieve a modest annual gain of 0.5–1.5 tC/ha for 20–25 years until a new steady state is achieved. At the same time, Conservation Agriculture promises bigger and more reliable crops with lesser, or even without, industrial inputs—which saves a lot of money. Simple calculation shows that by following a conservative crop rotation, the extra amount of grain produced on Chernozem across the four countries can be 64–128 million tonne per year—at least double present exports. A regenerative farming system can support renewal of rural communities, a food system based on local production of fresh food, and closer connection between producers and consumers. Mitigating global heating and increasing food security will, of course, take more than this; and it will also need concerted professional and political will.

The most remarkable thing about Chernozem is the production from unfertilized fields. In long-term trials on the Typical chernozem of the Balţi Steppe, the mean yield of winter wheat at 4 t/ha is equivalent to the best achieved anywhere in Europe up until the 1960s, double the average in Russia over recent decades, and a very good yield on dryland anywhere. Even after more than a century of hard labour, this is still the best soil in the world. Crop yields increased along with the introduction of various systems of fertilization but have levelled off during the last 20–25 years. In crop rotation, sugar beet and winter wheat respond well to fertilizer, corn and sunflower hardly at all; and the more mineral fertilizer applied, the less the nutrient-use efficiency. The extra yields obtained, even from low rates of fertilizer, even from the most responsive crops, do not cover their cost. We need to find more effective ways to use mineral fertilizers—or find an alternative. Pursuers of greater crop yields have turned a blind eye to the decline in soil fertility. The 30-year average annual losses of soil organic carbon by mineralization of soil organic matter from Typical chernozem under continuous winter wheat and corn, were 0.38–0.42 t/ha, and under crop rotation 0.26–0.29 t/ha. Greater inputs of nutrients from mineral fertilizers do not recoup such losses and this will limit any future, sustainable intensification of agriculture. In a good, diverse crop rotation, even with optimal use of manure and fertilizers, the share of inherent soil fertility in yield formation remains very high: 83–89% for winter wheat, 64–85% for sugar beet, 85–96% for corn and 75–83% for sunflower. Where farmyard manure is applied, supplementary mineral fertilizers are ineffective, so cost and environmental impact can be cut by not using them. Compared with continuous monocropping and abbreviated crop rotations, diverse rotations increase nutrient-use and water-use efficiency. Integration of crops and livestock within a crop rotation that includes perennial legumes and grasses makes good use of forage crops and by-products from the main crops. In turn, livestock return farmyard manure to the field, compensating for the nutrients taken up by crops and the organic matter broken down by mineralization. Perennial legumes and grasses resist drought by drawing water from deep in the soil. The recharge of soil water over winter is greater under crop rotation than under monoculture, and much greater than black fallow—which should be eschewed because of its inefficient consumption of water and destruction on soil organic matter.

Beyond the need to increase food production by 70% or even double by 2050, the diversion of rainfall away from replenishment of water resources to destructive runoff, the exploitation and contamination of streams and groundwater, and the contribution of agriculture to global heating are all pressing issues. Each and every one of them is a consequence of shortcomings in farming practice. Modern, industrialized agriculture is destroying the very resources that it depends upon: soil fertility, even the soil itself; water; biodiversity; and rural communities. Science has charts enough to plot a course for sustainable, climate-smart farming. At the field level, arrest of soil erosion, regeneration of soil fertility and resilience against weeds, pests and disease can be delivered by mimicking natural ecosystems. This may be achieved by maintaining a continuous surface cover of crops or a mulch of crop residues, minimal or zero tillage, diverse crop rotations that include perennial legumes and grasses, and integration of crops and livestock that enables the application of farmyard manure. Most of these practices are elements of Conservation Agriculture (CA) which is embraced by millions of farmers across the world. But these farmers remain a minority because sustainability requires not only the redesign of farming systems but probably, recasting the entire food system so that good husbandry is good for farmers as well as good for society. This is not a simple task and it doesn’t fall within the compass of any single discipline; the time is ripe for policymakers to lend a hand. Overcoming the barriers to sustainability requires policy interventions, logistical support and a new level of research and development by multidisciplinary teams able to deal with complexity.

Two giants of the nineteenth century, Dokuchaev and Liebig, established very different approaches to the world of the soil: one in the field, the other in the laboratory. Dokuchaev’s idea of soil as an independent natural body developing in its own time according to its own laws, has resonance in James Lovelock’s Gaia hypothesis. Liebig’s acclaimed Theory of Mineral Nutrition was based on chemical analysis of plants and soil; later in life, he learned better but his followers did not. He also perceived a link between the health of the soil, the ecosystem and human health, followed up by Haeckel at turn of the century, Howard in the 1940s, and many others. Politics demands cheap food: there is nothing more expensive. After the Second World War, a deft sidestep by the chemical industry, from munitions to agrochemicals, brought fertilizers and pesticides to the fore: the Green Revolution was spawned not only by new crop varieties and hybrids but by cheap power, chemicals and expansion of irrigation. This paradigm depends on fossil energy to the point that it expends more energy than it produces. It is mining the soil organic matter that fuels life in the soil and maintains the architecture that allows infiltration of rainfall, water supply to plants and drainage to streams and groundwater. This loss cannot be made good by mineral fertilizers but only by annually returning enough fresh organic residues and farmyard manure. Food production is unequally spread: most countries rely on imports and the projected human population in 2050 will require a 50–70% increase in production. Farm-gate prices have been forced down while the cost of inputs rises. The response has been bigger farms, bigger machinery, indiscriminate use of agrochemicals, and a smaller workforce. Sustainability demands replacement of this broken system by a systemic approach mimicking natural ecosystems: organization of the landscape according to the shape of the land; the least possible soil disturbance, retention of crop residues as mulch, diverse crop rotations; integration of crops and livestock; and translation of science into action for rural communities. Long-term field experiments began at Rothamsted in 1843, others followed and painstaking measurements reveal the damage brought about by modern farming systems. But a different way of doing things arose not from formal experiments but from farmers themselves. In 1943, Faulkner had the gall to oppose ploughing but, from the 1970s, zero tillage was extended into Conservation Agriculture (CA) by farmers in Brazil—as a matter of survival. CA has now been adopted by some 14% of all cropland but lowering the barriers to adoption will need constructive policies and interdisciplinary research.

As it stands, agriculture is unsustainable—economically, ecologically and socially. Its fundamental problem is the gross simplification of farming practice in pursuit of profit, aided and abetted by application of more power, more fertilizer, and more agrochemicals. A new concept of agricultural intensification is needed to make better use of natural resources and do less damage to the environment and society. Agroecology provides a rigorous basis for sustainable intensification. It draws on close observation of natural ecosystems; integrates biological and ecological processes such as soil regeneration, nutrient cycling, nitrogen fixation, allelopathy, and competition; and minimizes use of non-renewable inputs that harm the environment or the health of farmers and consumers. It also makes full use of farmers’ knowledge and skills, building self-reliance and substituting human capital for costly external inputs; and draws on collective capacity to solve common agricultural and natural resource problems. Fundamental features of natural ecosystems that should be respected in agroecosystems include: perennial vegetative cover or the nearest practical alternative that may include intercropping and cover crops as well as crop residues that protect the soil surface and conserve water; a regular supply of fresh organic matter that maintains soil biological activity; recycling augmented by a greater diversity of crops integrated with animal husbandry that regulate pests and diseases through heterogeneity at the field and landscape levels. A good example of mimicking natural ecosystems is the use within crop rotation of mixtures of perennial grasses, analogous to steppe or prairie vegetation. Structural changes in agriculture are needed to incorporate these principles into the existing farming systems. We should also undertake life cycle analysis of the whole food system—not only food production but also processing, marketing and consumption. Raising consumer awareness about the food quality and environmental health can assist the transition sustainability.

Carbon sequestration connects three issues crucial to society: land degradation, sustainable development and climate change. Climate change is driven by greenhouse gases in the atmosphere: the main driver is the build-up of CO2 emissions from land-use change and combustion of fossil fuels. Between 1850 and 1998, these amounted to 136 ± 30 and 270 ± 30 GtC, respectively; current annual emissions are around 1.6 and 7 Gt, respectively. Mineralization of soil organic carbon (SOC) has contributed most of the former: in Chernozem, replacement of perennial vegetation by annual crops has brought about the loss of 30–70% of its native carbon. Losses were greatest on breaking the sod but they are still significant because, in arable systems, annual inputs of organic matter do not match the annual losses. In long-term field experiments, sole use of mineral fertilizers doubled annual losses of SOC relative to unfertilized plots, and losses from the subsoil are greater than losses from the topsoil: 66–72% compared with 28–34%, respectively. All these losses are accelerated by irrigation. Nearly all Chernozem will surely remain as cropland but emissions can cut, or even reversed, by cutting energy-intensive industrial inputs: biological N fixation instead of mineral fertilizers, crop rotation to cut the use of pesticides, and zero tillage. Long-term field experiments on Chernozem in Canada comparing perennial cropping with wheat yielded a mean increase of SOC stocks in the 0–30 cm layer of 0.6 tC/ha/year; eschewing alternate years of black fallow in favour of continuous cropping increased stocks by 0.23 tC/ha/year); gains from zero tillage amounted to 0.14 tC/ha/year for the top 15 cm of the soil.