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Plant-soil feedback (PSF) describes the process whereby plant species modify the soil environment, which subsequently impacts the growth of the same or another plant species. Our aim was to explore PSF by two maize varieties (a landrace and a hybrid variety) and three arbuscular mycorrhizal fungi (AMF) species (Funneliformis mosseae, Claroideoglomus etunicatum, Gigaspora margarita, and the mixture). We carried out a pot experiment with a conditioning and a feedback phase to determine PSF with different species of AMF and with a non-mycorrhizal control. Sterilized soil was conditioned separately by each variety, with or without AMF; in the feedback phase, each soil community was used to grow each in its "home" soil and in the "away" soil. Plant performance was assessed as shoot biomass, phosphorus (P) concentration and P content, and fungal performance was assessed as mycorrhizal colonization and hyphal length density. Both maize varieties were differentially influenced by AMF in the conditioning phase. In the feedback phase, PSF was generally negative for non-mycorrhizal plants or when plants were colonized by G. margarita, whereas PSF was positive in the other three AMF treatments. When plants were grown on home soil, hyphal length density was larger than on away soil. We conclude that different maize varieties can strengthen positive plant-soil feedback for themselves through beneficial mutualists for themselves, but not across the maize varieties.

Escalating energy costs are an increasing concern for South Asian farmers growing rice and wheat in rotation. Millions of people in the IGP (Indo-Gangetic Plains) depend on this cropping system for food and income security. CT (conservation tillage) practices, including mechanical BP (bed planting), PTOS (power-tiller operated seeding), and ST (strip tillage), are advocated by donors and development organizations as profitable, high yielding, and energy-efficient alternatives to TT (traditional tillage). However, most studies on the EUE (energy input use efficiency) of CT originate from researcher-controlled and on-station experiments. Comparatively little information is available on the EUE of CT practices as farmers apply them in their own fields, and under their own management decisions. This research responds to this gap, and analyzes EUE of each of these three CT options, compared to TT, by surveying 328 rice-wheat farmers in north-western Bangladesh. Concentrating on wheat production, we employed a non-parametric benchmarking technique involving slack-based measures of technical efficiency, along with a fractional regression model to identify and compute the wasteful use of energy. PTOS achieved the highest EUE score (0.92), followed closely by BP and ST (both 0.91), whereas TT (0.68) was significantly (p <0.001) different and lower than the CT practices.

About 25 million tons of food go wasted or lost in Iran which has socio-economic and environmental consequences for both the country and the households. The main objective of this research is to develop a model to examine the relationship between FCM components and the amount of FW of households in Tehran city, with a focus on urban women. By means of a structural model, this study provides a novel approach to exploring relationships between the food-related behavior of urban households and waste control (n = 1197). Besides, this study is the first attempt to quantify food waste in Iran at the household level. According to the adopted self-reporting procedure, in Tehran, every consumer wastes about 27.6 kg of edible food annually. It is found that households with better food consumption management (FCM (have a lower level of food waste. Moreover, the results have proved that other determinants such as demographic factors, economic power, information use, ability, and motivation have direct and indirect significant effects on FCM as well as on the amount of food waste generation. The findings suggest that the above-mentioned determinants are crucial and should be considered when developing a strategically sustainable food waste prevention plan.

Policymakers at global level recognise that household biomass use in developing countries has significant health consequences. However, it is unclear how local-level health professionals perceive and respond to such health effects. This paper which is derived from the findings of a larger study on perceptions and responses to the harmful health effects of carrying heavy firewood loads and to smoke from cooking fires is based on a study conducted in South Africa among managers of health programmes and community nurses of Qaukeni and Mhlontlo municipalities in rural Eastern Cape. Interviews and participant observations were conducted in 2009 using ethnographic grounded theory approaches. In addition to a 10-month period of ethnographic fieldwork, ten programme managers and nurses in two villages were interviewed about health patterns in the villages that they serve, their perceptions of, and responses to the health effects of carrying heavy firewood loads, and inhalation of smoke from wood and dung cooking fires, their professional qualifications and experience, their own household energy use; and observations made as they served clinic clients. Results show that these programme managers and nurses perceive the health effects of carrying heavy loads of firewood and of cooking smoke as minor. Sometimes, nurses give women symptomatic relief for musculoskeletal pain resulting from carrying heavy loads. We posit that their perceptions are derived from customary neglect of work-related health and non-communicable diseases, cultural interpretations of womanhood, limited access to relevant information, and limited interactions between health and energy sector professionals. We conclude that culturally and gender-sensitive awareness programmes are needed for local-level health professionals to effectively address health effects of biomass collection and use. This paper provides new insights into overlooked differences between globally-driven initiatives to address health effects of biomass use and local perceptions.

Wood ash recycling to forests is beneficial because it regains nutrients and prevents acidification, but wood ash application is restricted due to its cadmium (Cd) content. We question if Cd in wood ash represents a problem, since decreases in Cd bioavailability due to ash-induced pH changes may counteract increased total Cd concentration. We studied effects of wood ash (0, 3, 9 and 30 t ha-1) and lime (pH increase equivalent to the wood ash treatments) on growth and Cd uptake in Deschampsia flexuosa. After four months, we measured plant biomass and Cd accumulation, and extracted Cd from the soil using three different methods; HNO3 (total), EDTA (chelator-based) and NH4NO3 (salt-based). Wood ash and lime strongly stimulated plant growth. Cd concentration in the plant tissue decreased with wood ash and lime addition, and correlated positively with the NH4NO3 extractable fraction of Cd in the soil. In contrast, HNO3 and EDTA extracted more Cd with increased wood ash application. We conclude that wood ash amendment increases soil pH, total Cd concentration, nutrient levels and stimulates plant growth. However, it does not increase Cd accumulation in D. flexuosa, as pH-driven decreases in Cd bioavailability leads to reduced plant Cd uptake. Finally, soil bioavailable Cd is best determined using NH4NO3-extraction.

To mitigate the climate change-induced water shortage and realize the sustainable development of agriculture, drip irrigation, a more efficient water-saving irrigation method, has been intensively implemented in most arid agricultural regions in the world. However, compared to traditional border irrigation, how drip irrigation affects the biophysical conditions in the cropland and how crops physiologically respond to changes in biophysical conditions in terms of water, heat and carbon exchange remain largely unknown. In view of the above situation, to reveal the mechanism of drip irrigation in improving spring wheat water productivity, paired field experiments based on drip irrigation and border irrigation were conducted to extensively monitor water and heat fluxes at a typical spring wheat field (Triticum aestivum L.) in Northwest China during 2017–2020. The results showed that drip irrigation improved yield by 10.3 % and crop water productivity (i.e., yield-to-evapotranspiration-ratio) by 15.6 %, but reduced LAI by 16.9 % in contrast with border irrigation. Under drip irrigation, the lateral development of spring wheat roots was promoted by higher soil temperature combined with frequent dry-wet alternation in the shallow soil layer (0–20 cm), which was the basis for efficient absorption of water and fertilizer, as well as efficient formation of photosynthate. Meanwhile, drip irrigation increased net radiation and decreased latent heat flux by inhibiting leaf growth, thereby increased sensible heat, causing a higher soil temperature (+1.10 ℃) and canopy temperature (+1.11 ℃). Further analysis proved that soil temperature was the key factor affecting yield formation. Based on the above conditions, the decrease in leaf distribution coefficient (−0.030) led to the decrease in evapotranspiration (−5.7 %) and the increase in ear distribution coefficient (+0.029). Therefore, drip irrigation emphasized the role of soil moisture in the soil-plant-atmosphere continuum, enhanced crop activity by increasing field temperature, especially soil temperature, and finally improved yield and water productivity via carbon reallocation. The study revealed the mechanism of drip irrigation for improving spring wheat yield, and would contribute to improving Earth system models in representing agricultural cropland ecosystems with drip irrigation and predicting the subsequent biophysical and biogeochemical feedbacks to climate change.

AbstractClimate change alters surface water availability (WA; precipitation minus evapotranspiration, P − ET) and consequently impacts agricultural production and societal water needs, leading to increasing concerns on the sustainability of water use. Although the direct effects of climate change on WA have long been recognized and assessed, indirect climate effects occurring through adjustments in terrestrial vegetation are more subtle and not yet fully quantified. To address this knowledge gap, here we investigate the interplay between climate‐induced changes in leaf area index (LAI) and ET and quantify its ultimate effect on WA during the period 1982–2016 at the global scale, using an ensemble of data‐driven products and land surface models. We show that ~44% of the global vegetated land has experienced a significant increase in growing season‐averaged LAI and climate change explains 33.5% of this greening signal. Such climate‐induced greening has enhanced ET of 0.051 ± 0.067 mm year−2 (mean ± SD), further amplifying the ongoing increase in ET directly driven by variations in climatic factors over 36.8% of the globe, and thus exacerbating the decline in WA prominently in drylands. These findings highlight the indirect impact of positive feedbacks in the land–climate system on the decline of WA, and call for an in‐depth evaluation of these phenomena in the design of local mitigation and adaptation plans.