4.3 Integrated soil-crop management practices

Integrated soil-crop management practices

Integrated soil-crop management practices can deliver higher yields and profits. In China, field experiments demonstrate that integrated soil-crop management practices, including reduction of nitrogen use by 4–14 percent in maize, rice, and wheat systems, can increase yields by 18–35 percent. Yields were increased from 7.2 metric tons per hectare to 8.5 metric tons per hectare without any increases in nitrogen fertilizer. Thus, a country with comparatively high rice yields can still increase productivity and reduce greenhouse gas emissions by managing nitrogen losses and using agronomic practices that control crop varieties, sowing dates, planting densities, and nutrient management practices (Chen et al. 2014).

Vietnam has implemented different input management programs with varying results. The “1 Must and 5 Reductions” (1M5R) program in Vietnam has shown that it could save Mekong Delta farmers an estimated 18–25 percent of their production costs per hectare without harming yields (Cassou, Jaffee, and Ru 2017). Developed by the International Rice Research Institute in collaboration with An Giang authorities, 1M5R calls for farmers to use certified seeds (the “1 Must”) while reducing the use of four production inputs (seed, water, pesticides, and chemical fertilizers) and postharvest losses (the “5 Reductions”). Based on pilot studies through nine cropping seasons during 2012–14, nguyen et al. (2015) estimate that 1M5R can potentially save farmers us$1.4 billion (32,000 billion Vietnamese dong) a year, assuming 4 million hectares of double-cropped rice. similar opportunities for yields, incomes, and the environment have also been identified in relation to the use of fertilizer (and water) to grow coffee in Vietnam’s Central Highlands region (Amarasinghe et al. 2015; Technoserve 2013).

The ‘’Three Reductions, Three Gains” (3R3G) project aimed to reduce production costs, improve farmers’ health, and protect the environment in irrigated rice production in Vietnam through the reduced use of seeds, nitrogen fertilizer, and pesticides. It was developed by the International Rice Research Institute and introduced to farmers in southern Vietnam in early 2000 through traditional extension work and mass media. Farm survey data provide evidence of the adoption of 3R3G primarily in lowering seed rates (Huelgas, Templeton, and Castanar 2008).

A “small farmer, large field” model in Vietnam improves economies of scale. small farmers often have limited means with which to invest in soil tests, power tools, and other technologies that enable precise application of chemicals. With limited landholdings, smallholders lack the opportunity to spread their fixed costs. The model has been promoted by province-level agricultural authorities to devise ways for small farmers to realize economies of scale without giving up their land rights. The model supports groups of 25–100 neighboring farms in managing the land as if it were a single farm. Farmers break down the walls between their plots, prepare the land together, manage water jointly, and plant the same varieties. Agriculture departments have encouraged farmers to form groups, facilitated contracts between groups and rice millers, and financed or provided land leveling, advisory, and other services (Cassou, Jaffee, and Ru 2017).

and (4) manure management of both ruminant and monogastric animals (table D.2 in appendix D). Improving overall energy efficiency is also a costeffective option but generally works best in intensive and industrial-scale production systems, or when coupled with on-farm biogas production and energy generation (GRA and sAI 2013).

Biotechnology has shown significant potential for reducing agriculture’s reliance on some of the most toxic pesticides. Genetically modified (GM) crops have been the fastest-adopted crop technology in the history of modern agriculture. Globally, the average impact of GM crop adoption was to reduce pesticide use by an average of 37 percent, increase crop yields by an average of 21 percent, and increase farm profits by an average of 69 percent.8 The impacts in developing

low- and middle-income countries were found to be larger than impacts in high-income countries (Klümper and Qaim 2014). The adoption of GM crops, for example, cotton and maize, that are pest tolerant or require less pesticide has also been fast and widespread in the East Asian countries that have endorsed them (table D.1 in appendix D). For example, the widespread adoption of Bacillus thuringiensis (Bt) cotton in China resulted in increased yields while reducing pesticide use and its negative health effects (box 4.4).

Organic agriculture is the most popular alternative farming system in the world. It is practiced in 162 countries and occupies about 1 percent of global cropland. The global sales of organic foods and beverages have grown from $63 billion in 2011 to nearly $166 billion in 2018 and are expected to reach about $320 billion by 2022. In 2011, most of these sales (90 percent ) were concentrated in north America and Europe, with Asia,9 latin America, and Africa being primarily export producers (Willer, lernoud, and Home 2013). Organic agriculture applies many sustainable production practices and delivers food with no pesticide residues (smith-spangler et al. 2012), greater energy efficiency and diversity, and enhanced soil carbon and quality (Alföldi et al. 2002; Mondelaers, Aertsens, and Van Huylenbroeck 2009). Yet it has received much criticism for inefficiency (Pickett 2013), lower yields (de Ponti, Rijk, and van Ittersum 2012), higher labor costs (Crowder and Reganold 2015), and reliance on more land to produce the same amount of produce (Trewawas 2001). some recognize organic agriculture as being important for future food security, whereas others project it to become irrelevant (Crowder and Reganold 2015). A meta-analysis of organic agriculture concludes that, despite lower yields (but higher premiums), organic agriculture was more profitable than conventional agriculture (Crowder and Reganold 2015). The large-scale potential of organic agriculture in East Asia, where both agricultural land and labor are increasingly limited, must be weighed against productivity, efficiency, and consumer demand for healthy foods. Organic agriculture may have greater potential, for example, within controlled conditions of vertical farming and rapidly growing urban agriculture in general (chapter 5).

Irrigation has an important role in improving productivity, sustainability, and resilience of agriculture in increasingly fragile water and climatic conditions. Irrigation played a significant part in the adoption of MVs (Alaofè et al. 2016; Hazell 2009) as well as in the expansion of plantation crops in East Asia (table 4.3). Improvements in water management, including in irrigation services and training, have also been important for enhancing agricultural production and food security (Bizikova et al. 2017; Darko et al. 2016). Given weather and climatic risks, it is expected that one-half to two-thirds of future gains in global crop production will come from irrigated land (Kadiresan and Khanal 2018).

Technical and social innovations in water management and policy are required to improve water use efficiency (Rosegrant and Cai 2002; Yang, Zhang, and Zehnder 2003). In most parts of the world, variations of field flooding are still used. More efficient methods, such as central pivot sprinkler systems, have been in use in high-income countries since the 1950s. Drip irrigation, that is, slow application of water directly to crops, can minimize evaporation and reach water efficiency levels of 95 percent. Adding sensors can further reduce water use by as much as 50 percent and increase yields by 10 percent or more (Goldman sachs 2016; Cornell university, InsEAD, and WIPO 2017). Farmers in northern China, where 75 percent of crop output is in irrigated land, increasingly resort to