Climate change and pollution are increasing drought, salinity and heavy metal contamination in food crops, and, in turn, decrease yield and threaten food safety. Salinity is caused by an excess of NaCl in soils. Salinity is a major abiotic stress for plants over 800 million hectares of land worldwide. Lokhande et al. show that shoreline purslane (Sesuvium portulacastrum) can be used for sand-dune fixation, desalination and phytoremediation in coastal regions.
Life on earth is impossible without plants and other photosynthetic organisms. Plants are the most important living organisms for the ecosystem because plant harvest sun energy and, in turn, all other living organisms feed on plant directly or indirectly. Plants are used for food, fiber and most recently for fuel. Pollinisators such are bees are necessary for the reproduction and survival of many plant species, including plants for food. However, industrial agriculture and the use of pesticides have strongly declined bees and other insect pollinators. This bee decline has already decreased global food production. A review article by Nicholls and Altieri discusses in detail the problems of pollinators and how to solve this problem with novel farming practices.
The 7 billion global population should grow to 9.2 billion by 2050. This increased population will increase by 70 % the demand for food production, notably due to new dietary habits in developing countries towards high quality food such as meat and milk. Additional agricultural land is limited. More agricultural land will be used to produce biofuel or fibre instead of food. Thus, we need to grow food on even less land, with less water, using less energy, fertiliser and pesticide. Popp et al. review worldwide crop losses due to pests, and advanced methods to reduce losses using chemical and biological methods.
Agricultural production is more and more unstable as a result of complex issues related to climate, markets and public policy. Farmers must therefore develop new farming systems adapted to changing conditions. For instance in south-western France, during summer, farmers increasingly move livestock from lower plains to high summer pastures in the Pyrenees mountains. This adaptation based on ancestral know-how is due to the increasing scarcity of herbage in lower plains in summer. Martin et al. review 41 new ideas for farming systems adapted to changing conditions.
Expansion of agricultural land use has increased emission of greenhouse gases, exacerbating climatic changes. Most agricultural soils have lost a large portion of their organic carbon, becoming a source of atmospheric CO2. In addition, agricultural soils can also be a major source of nitrous oxide and methane greenhouse gases. Stavi and Lal show that agroforestry and soil application of biochar can efficiently sequester large amounts of carbon over the long-run. In addition, these practices also increase agronomic productivity and support a range of ecosystem services. Payments to farmers and land managers for sequestrating carbon and improving ecosystem services is an important strategy for promoting the adoption of such practices.
Global warming forces agriculture to be productive under marginal conditions. However modern maize hybrids fail to meet this requirement. Although breeding has achieved spectacular progress in grain yield, yields at low plant population densities remain almost unchanged. Maize hybrids are indeed unable to take advantage of resource abundance at low populations. Consequently, the optimum population varies greatly across environments. Dr. Ioannis Tokatlidis reviews the consequences of climate change on crop sustainability under widely diverse environments, and proposes crop management strategies to address the situation.
In New Zealand 70% of the country’s electricity generation is already renewable. Plant biomass can be used for multiple forms of bioenergy, and there is a very large potential supply, depending on which global assessment is most accurate in terms of land area that could be available for biomass production. The most suitable plant species must be identified before the potential biomass production in a particular region can be quantified. This in turn depends on the degree of climatic adaptation by those species. A review article by Kerckhoffs and Renquist identified the most suitable crop species and assessed their production potential for use within the climatic range present in New Zealand.