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While climate change threatens global food security, health, and nutrition outcomes, Africa is more vulnerable because its economies largely depend on rain-fed agriculture. Thus, there is need for agricultural producers in Africa to employ robust adaptive measures that withstand the risks of climate change. However, the success of adaptation measures to climate change primarily depends on the communities’ knowledge or awareness of climate change and its risks. Nonetheless, existing empirical research is still limited to illuminate farmers’ awareness of the climate change problem. This study employs a Bayesian hierarchical logistic model, estimated using Hamiltonian Monte Carlo (HMC) methods, to empirically determine drivers of smallholder farmers’ awareness of climate change and its risks to agriculture in Zambia. The results suggest that on average, 77% of farmers in Zambia are aware of climate change and its risks to agriculture. We find socio-demographics, climate change information sources, climate change adaptive factors, and climate change impact-related shocks as predictors of the expression of climate change awareness. We suggest that farmers should be given all the necessary information about climate change and its risks to agriculture. Most importantly, the drivers identified can assist policymakers to provide the effective extension and advisory services that would enhance the understanding of climate change among farmers in synergy with appropriate farm-level climate-smart agricultural practices.

Nitrogen (N) deposition is known to significantly affect plant growth. Mycorrhizas play an important role in plant productivity, and plants of different mycorrhizal types respond differently to global change, which will inevitably affect plant response to N deposition. However, little is known about the differences of different mycorrhizas in biomass allocation of host plants in response to N addition. Here, a meta-analysis of data from N addition experiments was carried out to analyze the response of biomass in arbuscular mycorrhiza (AM) and ectomycorrhiza (ECM) plants to N addition. The results showed that biomass of leaf, stem, fine root (FR), and litter between AM and ECM plants responded differently to N addition (p < 0.05). Among them, biomass of leaf and stem in ECM plants (leaf: 46.89%; stem: 45.59%) was more sensitive (positively) to N addition than AM plants (leaf: 27.84%; stem: 10.30%) (p < 0.05). N addition suppressed biomass of FR in AM plants (−11.22%) but promoted that in ECM plants (13.77%). The effects on biomass also varied with different functional groups between AM and ECM plants. However, the N responses were influenced by other resources. When other treatments were added, biomass was less varied in AM plants compared to ECM plants. In addition, the N response of WB (whole biomass) and root biomass were positively correlated with annual temperature in ECM plants, but that in AM plants did not. The effects on shoot biomass in AM and ECM plants to N addition both decreased with annual temperature. The N response of root biomass increased with annual precipitation. It can be seen that different mycorrhizal types regulate the response of different plant organ biomass to N addition, which is significant for predicting ecosystem responses and feedback to environmental change.

Waterlogging can reduce crop yield by 20%–50% or more, and lack of efficient selection methods is an obstacle in plant breeding. The methods currently used are mainly indices based on germination ability in Petri dishes and leaf chlorosis in plants grown in waterlogged soils. Cultivation in oxygen-depleted nutrient solution is the ultimate waterlogging system. Therefore methods based on root growth inhibition and on fluorescence in plant material hydroponically grown in oxygen-depleted solution were evaluated against data on biomass accumulation in waterlogged soils. Both traits were correlated with waterlogging tolerance in soil, but since it was easier to measure fluorescence, this method was further evaluated. A selection of F2 plants with high and low fluorescence revealed a small but significant screening effect in F3 plants. A test of 175 Nordic cultivars showed large variations in chlorophyll fluorescence in leaves from oxygen-stressed seedlings, indicating that adaptation to waterlogging has gradually improved over the past 40–50 years with the introduction of new cultivars onto the market. However, precipitation also increased during the period and new cultivars may have inadvertently been adapted to this while breeding barley for grain yield. The results suggest that the hydroponic method can be used for screening barley populations, breeding lines or phenotyping of populations in developing markers for quantitative trait loci.

The global market’s sustainability demand for coffee as a result of environmental concerns has influenced coffee producers to practice green coffee production. The efforts to improve the environmental performance of coffee production should also consider the other sustainability aspects: energy and economics. Using a green fertilizer from agricultural biomass can lower carbon dioxide (CO2) emissions since the cultivation process, which is directly impacted by fertilizer use, has been identified as an environmental damage hotspot for coffee production. This study aims to determine the impact of coffee pulp biomass utilization on coffee production in terms of energy savings, CO2 emission reduction, and economic value added. The methodologies used were environmental Life Cycle Assessment, energy requirement analysis, life cycle costing, and eco-efficiency analysis. The study findings showed that using coffee pulp biomass in coffee cultivation impacted the energy savings, environmental damage reduction, and increased economic value added. Applying coffee pulp biomass can potentially reduce 39–87% of cumulative energy demand, 49.69–72% of CO2 emissions, and 6–26% of the economic value-added increase. Moreover, coffee pulp utilization as a fertilizer is recommended to be applied broadly to promote sustainable coffee production according to its beneficial impact. This study provided that scientific information farmers need to apply green fertilizers in coffee production.

Adaptive multi-paddock (AMP) grazing is a form of rotational grazing in which small paddocks are grazed with high densities of livestock for short periods, with long recovery periods prior to regrazing. We compared the fluxes of greenhouse gases (GHGs), including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), from soils of AMP-grazed grasslands to paired neighboring non-AMP-grazed grasslands across a climatic gradient in Alberta, Canada. We further tested GHG responses to changes in temperature (5 °C vs. 25 °C) and moisture levels (permanent wilting point (PWP), 40% of field capacity (0.4FC), or field capacity (FC)) in a 102-day laboratory incubation experiment. Extracellular enzyme activities (EEA), microbial biomass C (MBC) and N (MBN), and available-N were also measured on days 1, 13, and 102 of the incubation to evaluate biological associations with GHGs. The 102-day cumulative fluxes of CO2, N2O, and CH4 were affected by both temperature and moisture content (p < 0.001). While cumulative fluxes of N2O were independent of the grazing system, CH4 uptake was 1.5 times greater in soils from AMP-grazed than non-AMP-grazed grasslands (p < 0.001). There was an interaction of the grazing system by temperature (p < 0.05) on CO2 flux, with AMP soils emitting 17% more CO2 than non-AMP soils at 5 °C, but 18% less at 25 °C. The temperature sensitivity (Q10) of CO2 fluxes increased with soil moisture level (i.e., PWP < 0.4FC ≤ FC). Structural equation modelling indicated that the grazing system had no direct effect on CO2 or N2O fluxes, but had an effect on CH4 fluxes on days 1 and 13, indicating that CH4 uptake increased in association with AMP grazing. Increasing soil moisture level increased fluxes of GHGs—directly and indirectly—by influencing EEAs. Irrespective of the grazing system, the MBC was an indirect driver of CO2 emissions and CH4 uptake through its effects on soil EEAs. The relationships of N-acetyl-β glucosaminidase and β-glucosidase to N2O fluxes were subtle on day 1, and independent thereafter. AMP grazing indirectly affected N2O fluxes by influencing N-acetyl-β glucosaminidase on day 13. We conclude that AMP grazing has the potential to mitigate the impact of a warmer soil on GHG emissions by consuming more CH4 compared to non-AMP grazing in northern temperate grasslands, presumably by altering biogeochemical properties and processes.

Wheat occupies a special role in global food security since, in addition to providing 20% of our carbohydrates and protein, almost 25% of the global production is traded internationally. The importance of wheat for food security was recognised by the Chief Agricultural Scientists of the G20 group of countries when they endorsed the establishment of the Wheat Initiative in 2011. The Wheat Initiative was tasked with supporting the wheat research community by facilitating collaboration, information and resource sharing and helping to build the capacity to address challenges facing production in an increasingly variable environment. Many countries invest in wheat research. Innovations in wheat breeding and agronomy have delivered enormous gains over the past few decades, with the average global yield increasing from just over 1 tonne per hectare in the early 1960s to around 3.5 tonnes in the past decade. These gains are threatened by climate change, the rapidly rising financial and environmental costs of fertilizer, and pesticides, combined with declines in water availability for irrigation in many regions. The international wheat research community has worked to identify major opportunities to help ensure that global wheat production can meet demand. The outcomes of these discussions are presented in this paper.

Energy sustainability and environmental protection in general are at the heart of engineering and industry discussions. Countless efforts have been devoted to improving the energy efficiency of industrial processes and specifically to harnessing their waste energy sources. One such source is waste from agro-industrial processes, which is frequently characterized by increased temperatures and high polluting potential. There are multiple available choices for exploiting energy from such waste, but this paper proposes a new alternative technique that substantially improves the efficiency. Based on the technology of leveraging a hot liquid effluent for heating a process fluid, this system introduces a third liquid to be revalorized by drying that is placed in between the hot and cold liquids. By adding stirrers inside the heat exchanger, the thermal resistance of the third fluid is reduced to a negligible level. Thus, this system has almost the same advantages as the previous one, but with the added benefit that it allows drying of a third fluid. One of the specific applications of this proposed technology is using heat from waste effluents to obtain dried food products. In the present work, it was used to dry slaughterhouse blood to obtain so-called “blood meal”, a product with a high added value that is used as pet food or organic fertilizer, and also has many other industrial applications. As shown here, the new technique outperforms existing alternatives in terms of energy efficiency and economic profitability.