Soil degradation in semi-arid West Africa can be reversed by intensive organic matter applications, in particular from woody perennials. Scientists Felix et al. recently reviewed the effects of agroforestry and wood amendments on soil properties and crop yields in semi-arid West Africa. They reckon that the presence of shrubs and trees on agricultural fields has overall positive but variable effects on soil carbon stocks and cereal yields.
Arable soils tend to lose organic carbon in the Mexico áreas cultivated with maize. Scientists De León-González et al. studied the emissions of C-CO2 and soil organic carbon in a highland of central Mexico under different agricultural systems. They found that cultivation of perennial cactus crop in combination with maize production allows maintaining soil fertility, due to cactus crop root characteristics.
Changes in land management pattern, such as the way that grazing is organized, affect soil fertility. Scientists Cao et al. studied the soil fertility in the Qinghai-Tibetan Plateau. They observed that lands owned and managed by single families had their soils more severely degraded than those of lands collaboratively managed by multiple families.
Agricultural soils are under pressure due to increasing demands for producing food, feed, fibers, and other ecosystem services. Scientists Techen and Helming reviewed how many practices including higher precision and lightweight machines triggered by robotics provide more sustainable soil management. However, they plead for a better identification of possible threats connected to some of those practices.
Extensive practices of conservation tillage in northern China amend soil structure and nutrient availability, causing changes in the soil microbial community. Scientists Wang et al. show that conservation tillage favors rhizosphere soil bacteria diversity, which improves plant nutrition and accelerates growth.
Using plant residues as a mulch, modifies soil properties and enhances crop productivity potential under conservation agriculture. Scientists Ranaivoson et al. reviewed the benefits of mulch on soil water processes, soil erosion, soil nutrient supply, soil organic carbon, weed infestation and abundance of meso- and macrofauna. They showed evidence of improved performances with increasing amounts of surface crop residues.
Increasing carbon stocks in agricultural areas seeks to reinforce food security and affect climate change. In the context of the 4 per 1000 international initiative, scientists Dignac et al. review recent advances on the mechanisms of soil organic carbon stabilisation/destabilisation and show how agricultural practices influence these mechanisms. They show how these mechanisms can be integrated in global climatic models to ameliorate predictions of soil organic carbon stock evolution.
Soil erosion is a major issue for crop production, and is expected to increase with climate change. Measuring soil loss is difficult and few reliable methods are available. Agronomists Duan et al. designed a new method to calculate soil loss tolerance, taking into account soil productivity.
Global warming is induced by several factors, notably by the emission of greenhouse gases such as carbon dioxide (CO2) and nitrous oxide (N2O) by some agricultural practices. Agronomists Vermue et al. measured the nitrous oxide emissions of various weed management options. They found the highest emissions, of 5226 g per hectare, in the no tillage system, versus 177 g for intensive tillage. Most N2O emissions occurred in spring.
Conservation tillage is any method of soil cultivation that leaves the previous year’s crop residue, such as corn stalks or wheat stubble, on fields before and after planting the next crop, to reduce soil erosion and runoff. Presently, little is known about the effect of conservation tillage on soil microbes. Wang et al. show that conservation tillage increases the amount of bacteria species that are beneficial to crop production.