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.
In order to manage agricultural pests, the promotion of food resources and habitat quality to sustain natural enemies is a promising alternative to insecticides. Scientists Cahenzli et al. showed that abundance of spiders during the previous autumn reduced fruit damage caused by the rosy apple aphid during the following summer. Indeed, larger spider web areas caught more immigrating aphids in autumn, resulting in lower numbers of aphid fundatrices in the following spring and subsequently lower fruit damage.
The parasitic plant crenate broomrape is the major constraint for dry pea cultivation in the Mediterranean Basin and the Middle East. Scientists Fondevilla et al. identified pea breeding lines showing stable resistance to broomrape and high productivity. These lines will be particularly useful for the sustainable control of broomrape.
What are the convergence and divergence between organic agriculture and agroecology ? Scientists Migliorini and Wezel recently reviewed and compared the principles and practices defined and described in EU organic agriculture regulations, IFOAM norms, and scientific literature in agroecology. They concluded that although these two streams differ on some points, both offer promising contributions for a more sustainable agriculture, especially if their principles and practices transform the agro-food systems.
World cocoa intensive production lacks of sustainability and there is a need for more ecologically efficient cropping systems based on greater biodiversity level. However, the performances of cocoa agroforests are more difficult to assess than those of monospecific systems. For the first time, scientists Jagoret et al. demonstrate that the basal area per cocoa tree and the unproductive adult cocoa tree rate are key factors to assess cocoa yield. These indicators can be used to mediate the structure of a cocoa agroforests to improve their yields.
Conventional oil palm agriculture relies heavily on chemical herbicides to control weeds in plantations. The overuse of chemical herbicides has adverse impacts on the environment and biodiversity. Scientists Tohiran et al. show for the first time that targeted cattle grazing can control weeds and improve avian biodiversity. The application of targeted grazing as a biological control method for weeds is in line with the expectations of greater sustainability sought by palm oil consumers and certification bodies.
Direct-seeding rice production is increasing due to declining farm labor forces and expanding water scarcity worldwide. In this production system, speed of germination, field emergence and crop yield depend prominently on rice seed vigor. Scientists Simma et al. showed that wood vinegar, a byproduct of wood burning, may be used as a sustainable alternative to chemicals for rice seed priming.
Maximizing crop production while improving soil carbon storage and nitrogen-use efficiency is a major challenge in the sustainable intensification of agro-ecosystems. Agronomists Castelli et. al. compared four arable systems and a no-till permanent meadow during a 30 year field experiment. All ecosystems caused clear trade-offs between services. Both the no-till permanent meadow and the most productive annual rotation lead to win-lose solutions. Farmers, however, may justify high fertilization practices if their management goal is to spare land for less intensive uses such as permanent meadow.
In a context of global change that increases uncertainty for agriculture, biodiversity-based techniques may reveal promising to enhance farming system resilience. Scientists Casagrande et al. tracked the use of such techniques in five regions of France. They observed that the level of diversification is related to farm characteristics. Farmers under organic farming apply a large number of biodiversity-based techniques, but surprisingly, this is not the case for farmers under conservation agriculture. Enhancing knowledge exchange through networks could favor the broader application of such techniques.
Crop rotations and residues fulfill important agronomic functions but they are inadequately considered in product carbon footprint calculations. Scientists Brankatschk and Finkbeiner recalculated carbon footprints for bread, milk, first-generation biodiesel and second-generation bioethanol and showed that crop rotations and residues influence the results and should be considered in the process. Without inclusion of crop rotation effects, environmental advantages of improvements in agricultural practices enabled by crop rotations will remain undetected.