Cropping
Reduced-Tillage Increases nutrient concentrations (α-Carotene, Lutein, Phosphorus, and Calcium) in a winter squash crop.
This meta-analysis shows that smaller farms, on average, have higher yields and harbour greater crop and non-crop biodiversity at the farm and landscape scales than do larger farms. There is little conclusive evidence for differences in resource-use efficiency, greenhouse gas emission intensity and profits.
Organic cultivation (using cover crop and pruning residues) of fruit tree orchards (citrus, subtropical trees, treenuts, vineyards, and olives) contribute a 56% decrease in GHG (on an area basis) in comparison to conventional practices. Moreover, on a product basis, greenhouse gas emissions decreased by 39 % on average. This decrease of GHGs is accounted on the basis of C sequestration in soils which is due in turn to higher C input.
In maize‒tomato rotations, SOC increased by 12.6% (21.8 Mg C ha-1) with both WCC and composted poultry manure inputs, across the 2m profile. The addition of WCC to a conventionally managed system increased SOC stocks by 3.5% (1.44 Mg C ha-1) in the 0 to 30 cm layer, but decreased by 10.8% (14.86 Mg C ha-1) in the 30 to 200 cm layer, resulting in overall losses of 13.4 Mg C ha-1. If they only measured soil C in the top 30 cm, we would have assumed an increase in total soil C increased with WCC alone, whereas in reality significant losses in SOC occurred when considering the 2-m soil profile. Ignoring the subsoil carbon dynamics in deeper layers of soil fails to recognize potential opportunities for soil C sequestration, and may lead to false conclusions about the impact of management practices on C sequestration.
If linear growth in land under perennial staple production continues to 2040, and replaces only annual cropland, an additional ∼0.95 GtC could be sequestered.
Perennial vegetables represent 33–56% of cultivated vegetable species and occupy 6% of world vegetable cropland. Carbon sequestration potential from the new adoption of perennial vegetables is estimated at 22.7–280.6 MMT CO2-eq/yr on 4.6–26.4 Mha by 2050. Despite their distinct relevance to climate change mitigation and nutritional security, perennial vegetables receive little attention in the scientific literature.
Weeds in organic cropping systems probably assist in reducing animal pest and pathogen infestation
“Edge density” in cropping fields can promote functional biodiversity and increase yield through improved pollination and pest control
Ants and termites increase wheat yield by 36% from increased soil water infiltration due to their tunnels and improved soil nitrogen - they have similar functional roles to earthworms. They may provide valuable ecosystem services in dryland agriculture, which may become increasingly important for agricultural sustainability in arid climates.
Use of compost enhances drought resistance
Meta‐analysis of 3,049 paired measurements from 417 peer‐reviewed articles to examine the effects of three common “climate smart agriculture” management practices on SOC sequestration. Biochar applications represented the most effective approach for increasing SOC content (39%). Then cover crops (6%). Then conservation tillage (5%).
Pulses reduce use of inputs by fixing nitrogen and increasing ecological function through crop diversity. Pulses are not utilised to potential because of multiple system lock-ins.
Yields of maize and wheat are on average greater with higher concentrations of SOC (soil organic carbon). However, yield increases level off at ∼2 % SOC. Potential N fertilizer reductions associated with increasing SOC are 7 % and 5 % of global N fertilizer inputs across maize and wheat fields, respectively. Potential yield increases of 10±11 % (mean ± SD) for maize and 23±37 % for wheat amount to 32 % of the projected yield gap for maize and 60 % of that for wheat.
The possibility of farming without glyphosate is becoming an important issue facing the agri-food research and development sector. Contingency plans need to be formulated if that scenario becomes a reality. In this review, we briefly summarize international events that have led to this possible situation, describe current glyphosate usage in major agronomic field crops worldwide, outline possible alternatives to glyphosate in two agro-regions and perform bioeconomic model scenarios of southern Australian broadacre cropping systems without the herbicide. Model predictions suggest that we can farm profitably without glyphosate by consistently utilizing key non-herbicidal weed management practices combined with robust pre-emergence soil residual herbicide treatments. However, maintaining low weed seed banks will be challenging. If the social license to use glyphosate is revoked, what other pesticides will soon follow?
Biochar-enriched soil mitigated N2O and NO emissions for wheat production,
5-year study examining four contrasting farming systems in dryland eastern Washington State in terms of their impacts on total productivity, economic performance, and soil quality. The four systems were a conventional (CONV) winter wheat/spring wheat/spring pea rotation, typical for the area; a mixed crop-livestock (MIX) winter wheat/spring wheat/grazed winter pea forage rotation; an organic mixed crop-livestock (ORGcrop) rotation of 3 yr perennial alfalfa and grass/grazed pea forage/winter wheat; and an organic hay (ORGhay) continuous perennial alfalfa and grass system.
Overall, 1) organic hay, 2) organic mixed crop-livestock, 3) mixed crop-livestock, and 4) conventional in this order produced a gradation of forage production relative to cereal production from greatest to least, and also a gradation of economic and soil sustainability metrics from greatest to least. This study found that integrating perennial crops, such as alfalfa and forage grasses, into organic farming systems can build soil quality, be profitable, and supply nitrogen to succeeding grain crops.
Tested 8 grain crop sequences for dryland organic agriculture, some with quinoa. Crop sequence affected agronomic outcomes but weather caused greater differences. Economic returns from organic quinoa were moderate despite low yields. Using alfalfa in organic grain cropping systems can increase profits & reduce risk. Organic cropping systems financially outperformed a typical conventional system.
Linkage between soil fertility and pest incidence
The GHG burden of hemp cultivation is intermediate between perennial and traditional annual energy crops, but net fuel chain GHG abatement potential of 11 t/CO2 eq./ha/year in the mid yield estimate is comparable to perennial crops
Hemp LCA: A sensitivity analysis was performed to explore changes in results related to main inputs assumptions and, in particular, the environmental benefits associated with the replacement of conventional fertilisers (ammonium sulphate) with organic matter were highlighted.
The conservation of pollinator diversity is fundamental to maintaining sustainable agricultural systems and food security. Some agricultural systems support pollinator diversity, while others may lead to their decline. Previous studies have evaluated the impacts of agricultural intensification on pollinators in temperate climates regions, but in tropical regions these impacts have been evaluated by only very few studies. We conducted a study in southeastern Mexico, in order to understand the effects of three agricultural systems on bee diversity in a tropical landscape. We compared 18 sites at two different scales (plot scale and landscape scale). We found a link between agricultural system intensity level at the plot scale and forest proportion at the landscape scale: land use intensity was low at both scales in 7 polycultures, low at plot scale and high at landscape scale in 4 pastures, and high at both scales in 7 monocultures. We collected bees at all sites, and found an overall high bee richness, with a total of 127 species. Bee richness was compared across agricultural systems using diversity accumulation curves with iNEXT package. Both polycultures and pastures had significantly higher richness as monocultures. We constructed bee species guilds according to ecological and life-history traits (i.e. size, sociality and nesting) and found that whatever the trait considered, the species richness in the different agricultural systems was most often affected in the same way than the complete community richness. Our results show, for the first time in tropical conditions that agricultural systems with low-intensity farming practices and forested landscape allow the preservation of a significantly higher diversity of bees than agricultural systems with high-intensity farming practices and highly deforested landscape. Considering that bee diversity is key to maintaining crop productivity, these findings can help scientists, policy-makers, and community members design policies that support both agricultural production and biodiversity conservation in the tropics.
Most cropland in the United States is characterized by large monocultures, whose productivity is maintained through a strong reliance on costly tillage, external fertilizers, and pesticides (Schipanski et al., 2016). Despite this, farmers have developed a regenerative model of farm production that promotes soil health and biodiversity, while producing nutrient-dense farm products profitably. Little work has focused on the relative costs and benefits of novel regenerative farming operations, which necessitates studying in situ, farmer-defined best management practices. Here, we evaluate the relative effects of regenerative and conventional corn production systems on pest management services, soil conservation, and farmer profitability and productivity throughout the Northern Plains of the United States. Regenerative farming systems provided greater ecosystem services and profitability for farmers than an input-intensive model of corn production. Pests were 10-fold more abundant in insecticide-treated corn fields than on insecticide-free regenerative farms, indicating that farmers who proactively design pest-resilient food systems outperform farmers that react to pests chemically. Regenerative fields had 29% lower grain production but 78% higher profits over traditional corn production systems. Profit was positively correlated with the particulate organic matter of the soil, not yield. These results provide the basis for dialogue on ecologically based farming systems that could be used to simultaneously produce food while conserving our natural resource base: two factors that are pitted against one another in simplified food production systems. To attain this requires a systems-level shift on the farm; simply applying individual regenerative practices within the current production model will not likely produce the documented results.
The study on Cropland Footprints of Australian Dietary Choices finds that about one third of annual cropping in Australia goes to the production of discretionary foods
Last updated