Activity data from a 30-year on-farm experiment with six soil-management treatments were used to develop inventory data for environmental partial life-cycle assessment (LCA). The purpose was to compare the treatments based on environmental outcomes and evaluate conservation agriculture (CA) in Australia's dryland cropping zone. Multiple trade-offs were revealed that highlight the need for a nuanced approach to sustainable intensification and show that rules-based CA is not sufficient to guarantee low greenhouse gas (GHG) emissions, nor low overall environmental impact. Nutrient mining in dryland cropping even under CA can lead to losses in soil carbon that can double GHG intensity. In these systems, additional nutrient inputs can reduce the loss of soil carbon as well as net GHG emissions, demonstrating the critical need to include the effects of soil carbon change in LCA to prevent perverse outcomes. The treatment involving strategic tillage and nutrient balancing, along with stubble retention, had the lowest GHG intensity, but there was a trade-off with the higher embedded impacts across several other environmental categories. Higher fertiliser input could lead to toxicity impacts, due to heavy-metal content, that contribute significantly to the Human health endpoint. However, limitations in modelling such local, site-specific impacts were considerable and more research is needed to address this. In general, trade-offs were found to exist between impacts from on-farm activities versus upstream manufacture of inputs; between GHG emissions and land use (yield) versus other environmental categories; and between different on-farm GHG emission sources. Despite these trade-offs, the treatments all had similar overall scores in the Human health and Ecosystems damage categories. There was no single treatment with low, or high, impact scores across all environmental indicators, indicating that trade-offs need to be carefully considered when making farm-management decisions in the context of net-zero or carbon-neutral farming.

By improving soil properties, cover crops can reduce wind erosion and sand damage to emerging cotton (Gossypium hirsutum L.) plants. However, on the Texas High Plains, questions regarding cover crop water use and management factors that affect cotton lint yield are common and limit conservation adoption by regional producers. Studies were conducted near Lamesa, TX, USA, in 2017-2020 to evaluate cover crop species selection, seeding rate, and termination timing on cover crop biomass production and cotton yield in conventional and no-tillage systems. The no-till systems included two cover crop species, rye (Secale cereale L.) and wheat (Triticum aestivum L.) and were compared to a conventional tillage system. The cover crops were planted at two seeding rates, 34 and 68 kg ha(-1), and each plot was split into two termination timings: optimum, six to eight weeks prior to the planting of cotton, and late, which was two weeks after the optimum termination. Herbage mass was greater in the rye than the wheat cover crop in three of the four years tested, while the 68 kg ha(-1) seeding rate was greater than the low seeding rate in only one of four years for both rye and wheat. The later termination timing produced more herbage mass than the optimum in all four years. Treatments did not affect cotton plant populations and had a variable effect on yield. In general, cover crop biomass production did not reduce lint production compared to the conventional system.

Population growth and climate change are pushing the need for sustainable food production and reduced water usage in agriculture due to limited water resources. Irrigation and fertilization have been proposed to improve crop water and nutrient utilization and potentially sustain or boost yields with less water, but its effect on crop yield can vary widely. This study conducted a meta-analysis to examine the effects of climate, soil conditions, and agricultural practices on maize and wheat yields in field conditions, especially when irrigation and nitrogen fertilization are used. The researchers used systematic literature searches to gather data on grain yields for maize and wheat from peer-reviewed publications available on Web of Science and Google Scholar. In summary, the meta-analysis of 24 peer-reviewed studies, which included a total of more than 706 observations, revealed that the application of irrigation and fertilization resulted in a respective yield increase of 9.20% for maize and 17.32% for wheat grain. Average maize grain yield was 9539.15 kg ha-1 in the irrigation and fertilization treatment and 8661.57 kg ha-1 in the control. Similarly, average wheat grain yield was 7011.58 kg ha-1 in the irrigation and fertilization treatment and 5797.24 kg ha-1 in the control. The assessment of effect size heterogeneity showed that the study effect sizes were significantly heterogeneous. This research proposes that by combining effective field management methods with nitrogen fertilizer and irrigation, sustainable and climate-resilient agricultural production can be achieved while mitigating soil and environmental damage.