Legumes are plants that do not need nitrogen (N) fertilisation because legumes are plants that are able to fix atmospheric nitrogen (N2). In addition legumes can be used as ‘green’ fertilisers because legumes are N-rich and thus cropping legumes provides the soil with a cheap, sustainable source of N fertiliser. Legumes are also an excellent source of protein for feed and food. Nonetheless legume cropping land in Europe represents only less than 4% of arable land. The grounds for such a low cropping surface are discussed by Voisin et al. who analyse the production of forage and grain legumes in France since 1950. The authors propose changes to improve legume production.
Models to predict Mediterranean olive production
Olive oil is a major resource of the Mediterranean region. Olive oil production can be improved by understanding the reproductive biology of the olive tree on large areas, but research tools are actually missing.
Therefore Oteros et al. developed six crop models adapted to the Mediterranean Basin, using data from 17 sampling points during the last 20 years. The results reveal better prediction of olive production.
Silicon-rich manure for sustainable rice production
Rice is a plant that needs silicon (Si) as a nutrient to grow well. Silicon is an element of silica (SiO2) found commonly in sand. Rice yields decrease when soils are depleted in available silicon. A possible solution is to add silicon-rich manure to soils. Song et al performed a 10-year field experiment and found that adding silicon-rich manure doubled the amount of available silicon in soils. Using manure brings the additional benefit of recycling organic waste and providing other plant nutrients such as nitrogen and phosphorus
Benefits and risks of anaerobic digestate fertilisers
Intensive soil fertilization with mineral fertilizers has led to several issues such as high cost, nitrate pollution, and loss of soil carbon. Fertilization with organic wastes such as anaerobic digestates is an alternative for sustainable agriculture. Conflicting results in the literature have questioned the effectiveness of anaerobic digestates as organic fertilizers. The review by Roger Nkoa demonstrates the fertilizer values of anaerobic digestates. However, anaerobic digestates emit amonia (NH3) and contain copper (Cu), Zinc (Zn) and manganese (Mn) that could pollute the soil and the atmosphere upon repeated soil applications.
Organic barley contains more cancer-preventing lunasin
Lunasin is an anticancer peptide identified in soybean and cereals. The influence of cropping on lunasin content in cereals is poorly known. The article by Legzdina et al. reveals that organic cropping increased up to 92% lunasin content in spring barley, versus conventional cropping. Barley contains also other health-promoting compounds such as beta-glucans.
Cropping and soil bacterial diversity
Soil living organisms are essential for food production by recycling organic matter and providing sustainable plant nutrients. Agricultural practices may degrade soil life, by actually precise knowledge on the impact of cropping is poorly known at the microscale, in micro- and macro-aggregates. The article by Constancias et al. reveals that cropping highly reduced bacterial density and diversity at the microscale, compared to bulk soils. The findings show that cropping practices that preserve aggregate stability should be favoured to preserve soil microbial diversity, and in turn fertility and food production.
Irrigation increases soil carbon and greenhouse gas N2O emissions
Irrigation controls food production as plant do not grow without water. The article by Trost et al. review the effects of irrigation on soil carbon and greenhouse gas N2O emissions. Findings include that irrigation increases soil carbon up to 500 % in cultivated deserts and up to 35% in semiarid regions. In humid regions N2O emissions often increase after precipitation or irrigation.
Benefits of compost in agriculture
Climate change and most actual world food issues are linked directly or indirectly to soil loss of carbon and fertility. Here composting appears as a cheap and sustainable solution.The review by Martínez-Blanco et al. presents nine benefits of compost application to the soil. Composting practices are classified into short-term, mid-term, and long-term benefits.
Positive effects of sustainable land management
Agriculture production in developing countries must be increased to meet food demand for a growing population. This issue may be solved by sustainable land management such as organic fertilization, lower soil disturbance, incorporation of residues, terracing, water conservation and agroforestry. From the review of 160 studies Branca et al. deduce positive effects of sustainable management, such as higher crop yield and soil carbon sequestration.
Genetically modified crops or agriculture biodiversity?
The growing world demand for food is a major challenge for humankind. Increasing food production will be more and more difficult due to fewer arable land, less water availability, pollution, warmer climate, and land competition of food production with biofuel production and cities. As a result there is a strong on-going debate on the best strategy to keep pace with global population growth and increasing food demand. One strategy favors the use of genetically modified crops, while another focuses on agricultural diversity. The review by Jacobsen et al. places genetically modified crops far down the list of potential solutions and recommend funding in other research areas of plant science.