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Energy crops make modest but not negligible demands on soil nutrients. In grey forest soils in the Western Forest-Steppe of Ukraine and compared to rotational grain, legumes and oilseeds, 20-years cultivation of miscanthus brought about a decrease of 2.8 times of boron and 3.6 times of magnesium in the top 20 cm soil layer but an increase of 3.4 times in cobalt, 1.9 times in iron and 3 times in exchangeable calcium. Under Virginia mallow (Sida hermaphrodita L.), a reduction of boron by 1.4 times and 1.15 times of iron was found compared to soil under arable crops. The least difference between macro- and microelements was found under cup plant (Silphium perfoliatum L.). [ABSTRACT FROM AUTHOR]

Large-scale land acquisitions in Africa are increasing, reported often as the transfers of land for food and biofuel crop production. Only reporting agricultural acquisitions underplays potential impacts of other forms of acquisitions like tourism and conservation, which are new engines for economic growth in Southern Africa. While this shift has complex social-ecological implications, there is limited evidence of the multiple ways that land acquisitions unfold in wetland ecosystems, and implications for people and nature. This study aims to investigate local perceptions of implications of land and water acquisitions on local livelihoods in the Okavango Delta, Botswana, using in-depth interviews with 116 local respondents in Etsha 6, Khwai and Tubu villages. Findings revealed that the primary drivers of land acquisitions in the Okavango Delta were tourism and subsistence agriculture, and a new and unique land exchange (we termed land borrowing) was prevalent in Tubu, involving the borrowing of farmland in flood recessions between locals. Concessions, borrowings, and rentals were key perceived land acquisition types. Both positive and negative impacts of land acquisitions on livelihoods surfaced. The diversity of cultural grouping influenced locals' intricate connection with riparian waters and affected how land was exchanged and governed. The disparities in benefits from land resources have negative implications for equitable resource distribution and natural resource governance, in policy and practice. This research highlights the importance of an expanded view of acquisitions and associated impacts with closer attention to power dynamics which can facilitate more nuanced implementation of targets of the Kunming–Montreal Global Biodiversity framework. [ABSTRACT FROM AUTHOR]

Biochar amendment improves crop yield and mitigates climate change, but the lasting effect of biochar application on crop and soil properties under water scarcity conditions in tropical soils remains unexplored. We examined how a one-time biochar application alone and co-applied with vermicompost, with application rates of 25 and 50 ton ha−1, affected the growth of Zea mays L. and the related physicochemical and hydraulic properties of a clay soil after three years. Analyses included pH, electrical conductivity, the availability of cations and phosphorous, carbon to nitrogen ratio, soil water characteristics, crop growth and biomass. The results showed that 50 ton ha−1 of biochar co-applied with vermicompost produced more beneficial effects on the maize crop than 25 ton ha−1 biochar, in the first cycle and to a lesser extent in the third cropping season, caused mainly by the availability of phosphorous and potassium, and the enhancement of bulk density, porosity, and moisture retention. Our results suggest that a one-time application of biochar combined with vermicompost enhances maize growth under limited water conditions. However, further research is necessary to understand the long-term effect of biochar on the soil structure of clay soils, crucial for effectively managing crops in water-scarce conditions. [ABSTRACT FROM AUTHOR]

In the Middle Atlas rangelands, traditional methods for estimating standing crop biomass are labour-intensive and impractical. Remote sensing offers an initiative for standing crop biomass large-scale monitoring. The aim of this study was to estimate standing crop biomass, comprising annual and perennial forbs, grasses and perennial shrubs, using remote sensing data. The vegetation indices (NDVI, DVI, RVI, MSAVI and OSAVI) were derived from medium-resolution Landsat 8 and MODIS imagery. Sixty sampling sites were used for the biomass data collection. These sites were located across three grazing areas and data were collected in May and June 2016. Regression models were established between biomass field data and the five indices. Correlation analysis indicated that among the five vegetation indices, only DVI had the lowest value (r = 0.60). Linear models developed between the biomass field data and vegetation indices showed that NDVI, OSAVI and RVI explained a reasonable percentage of the variance in biomass. Values for R2 were 0.74, 0.77 and 0.71, respectively. Among these indices, the OSAVI performed better, with a high R2 and low error (MAPE = 11.03%). The established models represent a key tool for long-term monitoring of these rangelands. [ABSTRACT FROM AUTHOR]

Cover crops and nitrogen (N) fertilization may affect soil mineral N, N uptake, and N productivity (grain yield per unit plant available N) in wheat (Triticum aestivum L.). We evaluated the effect of summer cover crops and N fertilization rates on soil mineral N and winter wheat grain yield, N uptake, and N productivity in the Loess Plateau of China. We measured cover crop aboveground biomass N, soil mineral N (0-20 cm), and winter wheat yield, N uptake, and N productivity for four seasons from 2017-2018 to 2020-2021. Cover crops were soybean (Glycine max L., SB), sudangrass (Sorghum sudanense [Piper] Stapf, SG], soybean and sudangrass mixture (SS), and no cover crop (CK) and N fertilization rates were 0, 60, and 120 kg N ha−1 applied to wheat. The SB increased cover crop biomass N and soil mineral N by 15 to 65%, but SS increased winter wheat yield, protein concentration, and N uptake by 25 to 55% compared to SG and CK at most N fertilization rates and years. Nitrogen fertilization rate had a variable effect on cover crop and wheat parameters. Wheat N productivity was 55 to 85% greater with CK than cover crops, but decreased with increased N fertilization rates. The N fertilizer equivalence of cover crops for wheat yield and N uptake ranged from 31 kg N ha−1 for SG to 150 kg N ha−1 for SS. Overall, SS with 60 kg N ha−1 can sustain winter wheat N uptake and N productivity compared to SG or CK with or without N fertilization. [ABSTRACT FROM AUTHOR]

Forest and biomass crops for bioenergy and bioproducts can promote a sustainable bioeconomy while effectively reducing greenhouse gas (GHG) emissions to mitigate global warming. One of the most concerning issues is selecting and using appropriate modeling and analytical technologies to optimize the benefits of multi-feedstock biomass supply chains, including logistics. Machine learning (ML) has been used to solve increasingly complex supply chain problems, providing powerful tools for sustainable forest management and biomass resource development. Existing research is extensive and spans many different ML techniques, but synthesis is needed to help guide the adoption of these rapidly evolving tools. This review summarizes ML applications in forest and biomass supply chain management in terms of data, algorithms, and process examples, with an emphasis on direct application to supply chain management. ML is a viable technique to support strategic, operational, and tactical planning and decision-making in this field and can enhance the environmental and economic performance of diverse forest and biomass supply chains. [ABSTRACT FROM AUTHOR]

The huge volume of tannery solid waste (TSW) can be reduced through conversion into tannery solid waste biochar (TSWB). Here, it was used as soil amendment at seven levels and the total metals and their soil bound or exchangeable fractions were determined through sequential extraction. The fate of metals was observed using sunflower as a test plant in a greenhouse trial using field soil amended with six concentrations (0.45–2.7%) of TSWB. The amendment rate of 1.8% proved to be the best for the growth of sunflower. Sequential extraction of metals indicated that 40% or more Cd, Cr and Pb remained in the exchangeable fraction, compared to less than 20% of Cu, Fe and Ni. Copper was mainly bound in the Fe-Mn and organic fractions, while Fe and Ni were mainly bound in the residual fraction. Copper, Fe and Ni were therefore immobilized in TSWB, while Cd, Cr, Pb, Mg and Zn were available as indicated by differential uptake in sunflower. All metals, except Cd, remained within the permissible limit in tissues of sunflower, while all were in permissible limits in the seeds. As a result, TSWB can be used as amendment below 1.8% to grow energy crops like sunflower. [ABSTRACT FROM AUTHOR]

Soil cover biomass in integrated systems can improve agronomic characteristics and impact in soybean productivity. Thus, the objective is to evaluate the desiccation efficiency, biomass production, nutrient accumulation, and soybean productivity in Quênia guinea grass (Panicum maximum cv. BRS Quênia) biomass after with an intercropped with maize in different forms of seeding, in compare the conventional soybean. The experimental design was a randomized block with four replicates. The treatments consisted of cover crop biomass: maize monoculture; Quênia guinea grass monoculture; maize intercropped with Quênia guinea grass within rows; maize intercropped with Quênia guinea grass between rows and an additional soybean treatment without cover biomass. The results showed that the Quênia guinea grass in the different cropping systems presented high desiccation efficiency, showing potential as a cover plant in integrated systems. The intercropping system of maize with Quênia guinea grass between rows is more recommended than seeding in the same rows as maize, because it promotes greater biomass production and nutrient cycling, reflecting in higher soybean productivity. The integrated production systems is a promising and efficient technology for production systems compared to the system of monoculture maize and soybeans without soil cover biomass, which ensures greater sustainability of agricultural systems. [ABSTRACT FROM AUTHOR]

Toxic metals and metalloids, especially from anthropogenic sources, now pollute substantial areas of our planet. Phytoextraction is a proven technology with the potential to reduce metal/metalloid pollution, and where financially viable, recover valuable metals ('phytomining'). Toward these aims, there has been a surge of publications over the last two decades. While important progress is being made, ongoing propagation of poor practice, and the resultant drain from funding sources, is hindering this promising research area. This includes mis-ascribing hyperaccumulator species, hydroponics with extremely high dose levels, misuse of Bioconcentration Factors, use of food or biomass crops with low accumulation for phytoextraction, the phenomenon of 'template papers' in which a known hyperaccumulator for element X is dosed with element Y, or a common weed species dosed with any variety of elements to make it 'hyperaccumulate'. Here we highlight these misconceptions with the hope that this will help to: (i) disseminate accurate definitions for in planta metal accumulation; (ii) quash the propagation of poor practice by limiting the inflation of unnecessary publications via the practice of 'template paper' writing; (iii) be used by journal editors and reviewers to validate their reasoning to authors; and (iv) contribute to faster progress in delivering this technology to in-the-field practitioners. In this note, we highlight some common misconceptions with the hope that this will help to disseminate accurate definitions for hyperaccumulation, promote the appropriate use of hydroponics, and limit template paper writing. [ABSTRACT FROM AUTHOR]

The disposal of fly ash (FA) from coal power plants polluting the air, soil, and groundwater is a major environmental concern. Phytoremediation to rehabilitate fly ash dumpsites is a promising alternative but has practical concerns about the disposal of harvested biomass. This study investigated the effect of supplementing fly ash with fresh sewage sludge (FSS), aged sewage sludge, food waste, and compost (COM) to enhance the phytoremediation potential of Napier grass and its subsequent utilization for ethanol production. The highest removal of Mn (1196.12 g ha−1) and Ni (128.06 g ha−1) from FA could be obtained when Napier is grown in the presence of FSS and inorganic fertilizer (NPK). In addition, the highest bioethanol yield (19.31 g L−1) was obtained from Napier grown in fly ash with COM + NPK, thus providing additional economic benefits aside from the remediation process. Given the significant levels of heavy metals present in the pulp and bio-slurry after ethanol production, further research is required in this area to determine the best ways to utilize this waste such as converting it into biochar. Using energy crops as a phytoremediation agent for fly ash dumpsites has the potential to remediate heavy metal contamination and provide additional economic benefits. Napier grass was able to tolerate high concentrations of heavy metals and yield high biomass in fly ash in the presence of organic amendments. The harvested biomass was successfully converted into substrate for bioethanol production using heavy metal-tolerant yeast. This is the first report on the production of ethanol from the phytoremediation biomass of Napier grass. [ABSTRACT FROM AUTHOR]

The concentration of nitrogen in plants is usually determined through chemical analysis, although there are alternatives such as the measurement of chlorophyll as an indirect estimate of the nitrogen content. Currently, the reflectance, transmittance and fluorescence methods in specific regions of the spectrum are used to diagnose the nutritional status of plants in nitrogen. The objective has been to evaluate the use of sensors based on the principles of fluorescence and transmittance in the same test plots. The tests were carried out at the Valdegón Farm, at the Agro-food Technological Research and Development Center of the Government of La Rioja, at Agoncillo (La Rioja), Spain, in the years 2012, 2013 and 2014. Periodic sampling of nitrogen in soil, plant biomass and sheet measurements with Multiplex® were carried out. For the NBI index of the Multiplex high correlations have been found with the nitrogen content of the plant, which has served, depending on the phenological state of the crop, to adjust some functions that relate the measurements made with the biomass of the crop in the case of the NBI index. In the critical curves obtained for the sensors, it is observed that from a biomass of approximately 1 Mg/ha (50% of covered ground) the measurement stabilizes and it is from this moment when deficit treatments start to be distinguished from the non-deficit ones. Therefore, these models could be used to determine a nitrogen-based nutritional deficit and be able to correct it by fertilization. [ABSTRACT FROM AUTHOR]

The concentration of nitrogen in plants is usually determined through chemical analysis, although there are alternatives such as the measurement of chlorophyll as an indirect estimate of the nitrogen content. Currently, the reflectance, transmittance and fluorescence methods in specific regions of the spectrum are used to diagnose the nutritional status of plants in nitrogen. The objective has been to evaluate the use of sensors based on the principles of fluorescence and transmittance in the same test plots. The tests were carried out at the Valdegón Farm, at the Agro-food Technological Research and Development Center of the Government of La Rioja, at Agoncillo (La Rioja), Spain, in the years 2012, 2013 and 2014. Periodic sampling of nitrogen in soil, plant biomass and sheet measurements with Multiplex® were carried out. For the NBI index of the Multiplex high correlations have been found with the nitrogen content of the plant, which has served, depending on the phenological state of the crop, to adjust some functions that relate the measurements made with the biomass of the crop in the case of the NBI index. In the critical curves obtained for the sensors, it is observed that from a biomass of approximately 1 Mg/ha (50% of covered ground) the measurement stabilizes and it is from this moment when deficit treatments start to be distinguished from the non-deficit ones. Therefore, these models could be used to determine a nitrogen-based nutritional deficit and be able to correct it by fertilization. [ABSTRACT FROM AUTHOR]

Raphanus sativus (feral radish), a cosmopolitan weed, has developed resistance to acetohydroxyacid synthase inhibiting herbicides in several countries of South America. This study reports the effects of season-long interference of feral radish on grain yield and yield components of oilseed rape, wheat, and sunflower as well as on feral radish growth under field conditions. The number of inflorescences per area, seeds per inflorescence, and seed biomass of crops were reduced with increasing feral radish densities. The yields of winter crops were more severely affected than that of sunflower. The rectangular hyperbola model revealed yield losses up to 100% and 74.4% in oilseed rape and wheat, respectively, while only 12.2% in sunflower. Similarly, feral radish plants were substantially larger in competition with winter crops than with sunflower. Feral radish produced a maximum of 31,200 and 4700 seeds m−2 in winter crops and sunflower, respectively. Season-long feral radish interference can result in serious economic losses, especially in winter crops. Development and implementation of diverse and effective long-term weed management practices are needed. [ABSTRACT FROM AUTHOR]

This study evaluated the horizontal variability and diurnal fluctuation of soil respiration to accurately capture changes in carbon flux during agricultural production in Lishu County, Jilin Province, China. Corn (Zea mays L.) and soybean (Glycine max L.) were planted with 60-cm row spacing in 2020. The soil respiration rate (SRR) was measured at 2-hour intervals on July 1, August 1, and September 25 using a portable, closed chamber at five positions, P0, P15, P30, P45, and P60, denoting specific distances from the crop rows. The SRR between crop rows was affected both by dates and fields with the coefficient of variation ranging between 7.1 and 37.7%. The SRR at P45 was closest to the mean SRR, with a relative deviation of 0.09–4.85% on July 01 and August 01 in corn and soybean fields. On September 25, the optimal position to measure SRR was between P45 and P60. The sampling dates influenced the optimal time for measuring SRR but were mostly concentrated between 9:00 and 11:00 (24-hour clock) for corn and between 11:00 and 13:00 for soybean. The root biomass of crop rows and diurnal soil temperature were the main factors affecting horizontal variability and diurnal fluctuation of SRR, respectively. We recommend an SRR sampling strategy at P45 between 9:00 and 11:00 for corn and between 11:00 and 13:00 for soybean to decrease the effects of horizontal variability and diurnal fluctuation of SRR. [ABSTRACT FROM AUTHOR]

There is a growing interest in developing agricultural practices that can improve crop performance while preserving natural resources. Plant biostimulants are thought to play a role in reaching this goal, in particular by increasing the nitrogen use efficiency. However, a notable research gap exists concerning the effects of foliar applications of natural zeolites as plant biostimulants on crop performance. To address this knowledge gap, a greenhouse experiment was set up in order to study the response of maize and wheat traits, specifically the biomass productivity and nitrogen uptake, as well as the response of soil extracellular enzymes to the foliar applications of a natural zeolite in combination with different levels of nitrogen fertilization, that is, 100%, 75%, and 50% of the optimal dose. Foliar application of zeolite in wheat and maize plants led to an increase in root nitrogen concentration of about 10%, particularly at the lowest nitrogen fertilization rate. This response was accompanied by an increase in aboveground to belowground uptake nitrogen ratio. Furthermore, there was a significant reduction of about 20% in root biomass in both crops with zeolite application across the entire nitrogen fertilization gradient. These plant-level responses were associated with a significant increase in the activity of carbon-degrading and nitrogen-degrading enzymes at the soil level in response to zeolite applications. Our findings provide a compelling proof-of-concept for the beneficial effects of foliar-applied zeolite as a biostimulant for crops, emphasizing the critical need for additional field research to validate our greenhouse results. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to explore the effects of copper (Cu) tailings with various proportions in the substrate on seed germination and morphological traits of the plant. Concurrently, to identify the adaptive and tolerance strategies of the plant to Cu tailings, the uptake and accumulation of the plant to heavy metals, variations in soil enzymatic activities, and metal speciation in the blank, rhizospheric, and non-rhizospheric soils were estimated. Cu tailings at 25% proportion in the substrate exerted no significant negative effects on seed germination and seedling growth. However, Cu tailings at higher proportions (≧50%) inhibited seed germination and disturbed the plant physiological metabolism and growth. More biomass allocated to the plant roots could contribute to more heavy metals being immobilized, arresting their translocation from roots to shoots. This was accepted as a crucial defense mechanism for the plant against heavy metal co-contamination. The plant can improve the biological properties of Cu tailings in terms of enhanced invertase and phosphatase activities. And in turn, this can effectively alleviate heavy metal phytotoxicity. Simultaneously, it markedly decreased exchangeable Cu and Zn content in the rhizosphere in 25% Cu tailings treatments. In 50% Cu tailings treatment, no differences were observed in Zn speciation between rhizosphere and non-rhizosphere soils. In 75% Cu tailings, compared to the non-rhizosphere, an obvious reduction in exchangeable Cu in rhizosphere occurred, while an opposite tendency was demonstrated in carbonate-bound Zn. The plant could successfully colonize in Cu tailings, and represent a phytoremediation potential in Cu tailings. [ABSTRACT FROM AUTHOR]

The nitrogen nutrition index (NNI) as an effective indicator for monitoring crop nitrogen (N) status has multiple applications in agriculture, such as estimating in-season crop N requirement (NR), predicting crop biomass/yield, and improving N use efficiency. The present study was aimed to develop basil (Ocimum basilicum L.) NR and relative biomass (RB) prediction models based on the concept of critical N concentration. Two experiments were carried out with different N application rates in the research greenhouse of University of Tehran, Iran. Basil NNI values were calculated using the previously developed critical N dilution curve. Subsequently, the in-season basil NR estimation model was developed as a function of NNI, N recovery efficiency (NRE) and plant age. Additionally, basil RB was simulated as a function of the averaged and integrated NNI based on a linear-plateau model. Moreover, a theoretical relationship between N utilization efficiency (NUtE) and the NNI was established. The validation results of the developed NR-NNI model demonstrated a good performance with a root mean square error (RMSE) and a normalized root mean square error (NRMSE) less than 5.28 kg ha−1 and 4.72%, respectively. The results showed that crop biomass and NNI were the most significant explanatory factors for the variations in basil NUtE. Therefore, the crop NNI can serve as a practical in-season diagnostic tool for basil NR and RB prediction, while also contributing to the design of decision support systems and sustainable agro-ecosystems. [ABSTRACT FROM AUTHOR]

Increasing population and subsequent increase in waste necessitate recycling of waste products to minimize the environmental burden. This study was conducted in semi-arid tropics of Punjab to evaluate different rates of sludge application as a supplementary source of nutrients to conventional fertilizers in maize. The grain yield was significantly higher with the application of 5 t ha−1 sludge over control and marginally lower than in 10 t ha−1. Cadmium (Cd), chromium (Cr), lead (Pb), and nickel (Ni) in grains were below international standards even after maximum dose of sludge treatment and can be declared as safe for consumption. The bioconcentration factor of Cd and Ni increased by 82% and 49% with 10 t ha−1 over control, respectively while it remained same for Cr and Pb. Significant increase in exchangeable Cd, Pb in carbonate, and easily reducible oxide, Ni and Cr in residual fraction with 10 t ha−1 sludge over control were found. Mobility of only Pb and Cd increased with increasing sludge treatment. Conclusively, sludge application can be beneficial in increasing plant biomass, however heavy metal accumulation in plants may limit its use. Long-term effect of sludge applications as nutrient sources must be evaluated to get more in-depth insights. [ABSTRACT FROM AUTHOR]

Water and energy crisis, rising temperature and subsequent changes in climate result in calamitous loss of wheat productivity due to adverse effect on plant growth and development. Plateauing yield trends and declining total factor productivity compel for alternative water and energy-efficient conservation practices supporting sustainable wheat productivity in humid tropics. Present investigation tested the hypothesis stating that the alternate wheat establishment methods and inter-culture practices would economize energy and water requirement with enhanced productivity. Different wheat establishment methods viz., conventional tillage, reduced tillage, zero tillage and raised bed landforms of 40/20 and 60/20 cm and two inter-culture practices, i.e. conoweeding and alternate ridging on spring wheat were evaluated for two years at Pantnagar in Uttarakhand, India. Zero and reduced tillage depicted better economic viability with benefit cost ratio of 2.86 and 2.84, respectively, which was statistically at par with conventional tillage. Alternate ridging and raised bed (60/20 cm) recorded 13.3 and 41.7% saving of irrigation water, respectively. Highest energy use efficiency was observed in raised bed 60/20 cm with 22.4% less energy consumption compared to conventional method. Thus, adoption of conservation practices with improved inter-culture operations holds potential for sustainable, water and energy-efficient and profitable wheat productivity. [ABSTRACT FROM AUTHOR]

One benefit of cover cropping is nutrient provision, which can be optimized by management practices to synchronize nutrient releases from residue decomposition with the demands of subsequent cash crops. In the present study, we investigated how termination timing affects the decomposition of cereal rye (Secale cereale L.) residues and the release of associated nutrients. Field experiments were conducted in 2019 and 2020 in typical Ultisols of the Southeastern U.S. with soybean (Glycine max L.) and corn (Zea mays L.) rotation. Cover crops were drill-seeded and terminated 1-, 2-, 3- and 4-week before cash crop planting. Litter bag method and a two-parameter exponential decaying model were applied to estimate residue decomposition and nutrient releases. In 2019, cover crop biomass production ranged from 5757 to 6520 kg ha−1, which was not affected by termination timing. In contrast, cover crop biomass increased when delaying termination by 1 week in 2020. Cover crop provided up to 82 kg nitrogen (N) ha−1, 15 kg phosphorous (P) ha−1, and 89 kg potassium (K) ha−1 in 2019. As expected, terminating cover crops at 1-week intervals resulted in different decomposition rates but imposed inconsistent effects on N, P, and K releases. There was no difference in N, P, and K content in cash crops. However, cover cropping resulted in higher corn yields than control plots when terminated at 4-week before corn planting. The results suggested that cover crops can have significant nutrient benefits in the tested soils and climatic conditions, but optimal management is the key to realizing the potential. [ABSTRACT FROM AUTHOR]

Winter rye (Secale cereale L.) biomass and chemical composition influences decomposition rates, nutrient cycling and effects on cash crop growth. Management that maintains rye biomass while lowering carbon (C) to nitrogen (N) ratios and concentrations of structural carbohydrates including hemicellulose, cellulose, and lignin could maintain some ecosystem services while accelerating nutrient cycling. Two independent studies examined (1) five rye seeding rates ranging from 0 to 90 kg ha−1 and (2) five termination dates ranging from April 19 to May 31 (585 to 1084 growing degree days) to understand management induced relationships between rye biomass, nutrient concentrations, and composition of hemicellulose, cellulose, and lignin. Rye biomass increased at seeding rates of 90 kg ha−1 as compared to the 22–67 kg ha−1 seeding rates while trends toward higher plant structural components were observed as seeding rate increased. Rye biomass accumulated rapidly beyond 819 (May 13) growing degree days while increasing rye C:N ratio and concentrations of hemicellulose and cellulose. Rye C:N ratio was strongly correlated to rye biomass (R2 = 0.80, p <.001) with a C:N ratio of 25 associated with 2000 kg ha−1 of rye biomass. Changes in rye residue quality were strongly influenced by biomass accumulation with delaying termination most significantly driving biomass changes. Trends toward lower C:N ratios and concentrations of structural carbohydrates were seen at the 22–67 kg ha−1 seeding rates even without differences in biomass suggesting lower seeding rates could cycle nutrients quicker without limiting biomass production potential. [ABSTRACT FROM AUTHOR]

This research work was aimed at isolating and demonstrating the significant potential of autochthonous fungi for phytoextraction of hazardous metals in metal polluted soil using Helianthus annuus. Four multi-metal resistant strains of Trichoderma were selected from a total of 21 strains isolated from tannery polluted soil and tannery solid waste. Autochthonous Trichoderma strains were used singly and in the form of consortium (TC). Sunflower was grown in pots for 90 days having eight different amendments of tannery polluted soil with and without Trichoderma inoculation. Growth and biochemical attributes of the plants were observed along with metal content extract by different plant parts. The results revealed that TC enhanced shoot length, shoot dry weight, and metal uptake as compared to single specie inoculation. Similarly, BCF (72.8–118.23%) and TF were significantly pronounced in shoots of H. annuus grown with TC at 40% amended soil. The biochemical analysis of the plants showed that Trichoderma strains boosted the enzymatic (catalase, peroxidase, and superoxide dismutase) antioxidants in the plants. The use of indigenous fungi with metal accumulating plants like sunflower can help to alleviate metal contamination from industrial sites and can make the soil cultivable for energy crops. The genus Trichoderma is among the most common cosmopolitan soil fungi that enhance phytoextraction capability of plants. Hence, the isolation and identification of diversified and potent Trichoderma strains from contaminated environments is the need of the hour for broad spectrum applications in bioremediation. In the present study, contaminated soil mycoflora was explored and multi-metal resistant strains of Trichoderma were isolated. Their application in myco-assisted phytoextraction with Helianthus annuus was assessed to analyze their impact on the metal removal efficacy and enhancing growth in highly contaminated soil. [ABSTRACT FROM AUTHOR]

Sustainable weed management strategies are important for reducing chemical inputs and development of weed resistance. This study aimed to evaluate the effect of extracts from winter cover crops (cereal rye, black oat, forage turnip, and common vetch) and summer cover crops (jack bean, velvet bean, and brown hemp) on seed germination and seedling growth of glossy nightshade (Solanum americanum Mill), under controlled conditions. The aqueous extracts were produced from the shoot biomass of cover crops at concentrations of 0%, 25%, 50%, 75%, and 100%. Fifty S. americanum seeds were placed on Germitest paper moistened with 15 mL of each extract concentration. Cereal rye extract at the highest concentration reduced total germination to 43% and caused a 62% reduction in the germination rate index (GRI) of S. americanum. Velvet bean extract reduced germination, GRI, and seedling growth of S. americanum from the lowest concentration applied, while concentrations of 75% and 100% completely suppressed seedling development. Decomposing cereal rye and velvet bean cover crops have potential to suppress germination and growth of S. americanum. Efficient cover crops could reduce herbicide applications, and thus improve herbicide resistance management. [ABSTRACT FROM AUTHOR]

Atmospheric carbon dioxide concentrations ([CO2]) are increasing, but little is known about how this will affect macronutrient (nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)) accumulation and partitioning in the aboveground biomass (AGB) for different hard spring wheat genotypes. We examined the responses of six spring wheat genotypes ('Discovery', 'Duchess', 'Reliance', PFR-3026, PFR-3019, PFR-2021) to two CO2 levels (ambient [aCO2] and elevated [eCO2]) and six nitrogen rates (N; 1–10 mM), at the stem elongation growth stage of wheat grown in controlled environment chambers. The AGB yield increased by 35.2% with increasing [CO2] when N rate was >2 mM. Increasing N supply also increased AGB by up to 3.2-fold over the entire N range applied. The AGB responses to N differed among the genotypes, being lowest for PFR-3019 (7.71 ± 0.11 g/pot) and highest for PFR-2021, PFR-3026 and Duchess at 8.84 ± 0.11 g/pot at both CO2 levels. Macronutrient concentrations decreased with eCO2 by 28.0% for Ca to 17.4% for P and K. Nevertheless, absolute nutrient uptake was higher for eCO2 treatments, because the AGB increase (20.0–52.0%) was proportionally higher than the 4.0–28.0% increase in nutrient uptake. The AGB non-response to [CO2] at N rates <2mM indicates that this nutrient deficiency was more limiting than the effects of CO2 level. Therefore, the impact of eCO2 in the future will depend on N fertilizer management. These results suggest that critical nutrient concentrations used to diagnose the nutrient status of wheat crops will need to be reassessed for eCO2 conditions. [ABSTRACT FROM AUTHOR]

Appropriate nitrogen (N) fertilization in vegetable-maize rotations is effective in improving agricultural production and mitigating environmental impacts to ensure sustainable food security. The dynamic and sustainability of crop yields, crop root biomasses, and accumulations and sequestration rates of soil organic C (SOC) and total N (STN) were explored and analyzed under four N application rates (kg N ha−1 year−1): 0 (Control), 285 (Low-N), 480 (Medium-N), and 720 (High-N). The Low-N and Medium-N applications increased Chinese cabbage yield by 22% and 20.7% than the High-N application, respectively. The Medium-N application gained the highest grain yield and root biomass in the maize season when compared with the Low-N application. The sustainable yield index had no difference between Low-N and Medium-N treatments in Chinese cabbage-maize rotation. Compared to the Low-N application, the Medium-N application improved the storage and sequestration rates of SOC and STN. Simultaneously, the Medium-N application significantly enhanced the soil C:N ratio than the High-N application. In conclusion, the Medium-N application is a promising fertilization strategy in the Chinese cabbage-maize cropping system as it increases the yield and root biomass of crops, improves the accumulation and sequestration rates of SOC and STN, and maintains a high soil C:N ratio. [ABSTRACT FROM AUTHOR]

Miscanthus x giganteus (Miscanthus) grass shelterbelts can deliver multiple ecosystem services on New Zealand commercial dairy farms. However, there has been little investigation into how these shelterbelts contribute to insect pest management. Here, on a Canterbury dairy farm, we investigated what generalist surface-dwelling invertebrate natural enemies of insect pests inhabit three separate Miscanthus shelterbelts compared to three unmanipulated field margin plots. The potential contribution of these natural enemy assemblages to future biological control was also investigated. To measure this, live moth egg baits with associated pitfall trapping were deployed in autumn, winter and spring of 2015. Miscanthus and the field margin plots were found to have similar potential natural enemy richness but differed in their community composition. The potential predation rate of pests in Miscanthus was 85% higher than in the field margin. Infrared video and Sanger sequencing confirmed that the harvestman Phalangium opilio and the slug Deroceras reticulatum consumed the egg baits in Miscanthus. Conversely, no bait-consuming invertebrates were identified in the field margin. These preliminary results indicate potential natural enemies inhabit Miscanthus and may consume insect pest eggs on the soil-surface. However, to achieve anyinsect pest suppression, further habitat manipulation would be required. [ABSTRACT FROM AUTHOR]

Russia's invasion of Ukraine has taken almost 2 million ha of land out of agricultural production. Every day of conflict increases the extent and severity of the damage. Here, we highlight the possibility of bringing soils back to life by growing energy crops. In our example – a heavy loam Podzolised chernozem – significant improvement of several agrochemical, physical, and biological parameters has been achieved, which promises an increase in the quality of ecosystem services that the soil can provide. [ABSTRACT FROM AUTHOR]

Much of Ukraine's soil has been and is still being degraded by military operations. Its revival will need a lot of organic matter, much of which can be provided by municipal sewage sludge. Any associated environmental risks may be minimised by applying the sludge to energy crops, in particular, Miscanthus x giganteus. The introduction of municipal sewage sludge at the rate of 20-40t/ha, or composted with straw, increases the content of total and mobile forms of heavy metals in the soil. But, the resulting concentrations of heavy metals remain well within permissible limits. The integral indicator of soil cover pollution for applications of various kinds of fertiliser applied at a rate equivalent to N90P90K90 fluctuates within insignificant limits (20–23) with a tendency to increase in treatments with the highest rate of application of sewage sludge. [ABSTRACT FROM AUTHOR]

Miscanthus has been grown on four kinds of Technosols. These soil materials have relatively low levels of macronutrients and imperfect nutrient balance. Even so, miscanthus is able to produce substantial, stable yields from the third year of cultivation. The poorest yields were obtained on dark-grey schist clay; the highest on loess-like loam and red-brown clay. Miscanthus actively accumulates macronutrients, especially sulphur, whereas sodium and magnesium are accumulated in the smallest amounts; potassium and phosphorus are mainly accumulated in the stems, calcium and sulphur in the leaves. [ABSTRACT FROM AUTHOR]

The form and opener configuration used to apply phosphorus fertilizer can influence its effectiveness and crop response. A growth chamber study was conducted to examine the response of crop (canola, wheat, and pea grown in rotation) and soil to P fertilizer form (monoammonium phosphate and struvite), opener spread (narrow versus wide), and rate treatments of 0, 20, 40, and 60 kg P2O5 ha−1 added to canola (B. napus) in the seed-row, followed by wheat and pea without P fertilization to examine residual effects. Crop emergence, 30 days above ground biomass yield, uptake of P and apparent recovery of fertilizer P were determined, along with labile soil residual P concentrations at the end of the rotation. Both MAP and struvite produced similar crop biomass yield and P uptake response. The narrow opener spread (1") performed better in canola yield response to added P and in recovery of P fertilizer compared to the wide (3") spacing and did not appear to reduce canola emergence even at the highest rates of added P fertilizers. [ABSTRACT FROM AUTHOR]

To clarify the mechanism of the response of sugar beet (Beta vulgaris L.) to cadmium (Cd) stress, this study investigated changes in the phenotype, physiological indexes, and subcellular structure of B. vulgaris under Cd treatment and the transcriptional pattern of the BvHIPP24 gene (a heavy metal-associated isoprenylated plant protein involved in heavy metal detoxification). The plant height and shoot and root growth of B. vulgaris seedlings were inhibited to some extent under 0.5 and 1 mM Cd, with gradually wilting and yellowing of leaves and dark brown roots. When the Cd concentration was increased, malondialdehyde content and the activities of peroxidase, superoxide dismutase, and glutathione S-transferase increased differentially. qPCR indicated that the expression of BvHIPP24 was induced by different concentrations of Cd. Although transmission electron microscopy revealed damage to nuclei, mitochondria, and chloroplasts, B. vulgaris exhibited strong adaptability to 0.5 mM Cd according to a comprehensive analysis using the membership function. The results showed that B. vulgaris may reduce cell damage and improve its Cd tolerance by regulating functional gene expression and antioxidant enzymes. This study increases our understanding of the Cd-tolerance mechanism of B. vulgaris and provides insights into the use of B. vulgaris in Cd bioremediation. Sugar beet is a novel energy crop with superior characteristics for both heavy metal phytoremediation and biomass energy development. This work is the first to investigate both the morphological, physiological, and ultrastructural response of sugar beet to cadmium stress and the induction of a functional metallochaperone gene by cadmium. This study explains the cadmium tolerance mechanism of sugar beet based on a comprehensive evaluation and provides an important theoretical basis for further application of beet in heavy metal bioremediation. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the content, uptake, and utilization of Al, Mn, Fe, Co, and Mo from municipal sewage sludge by the reed canary grass (RCG) and the giant miscanthus (MG). The impact of sewage sludge on the mass ratios between microelements contained in the plant biomass was analyzed as well. The long-term field experiment consisted in application of four levels of fertilization with sewage sludge: 10, 20, 40, and 60 Mg DM·ha−1. A non-fertilized control object (0 Mg DM·ha−1) was used as well. The miscanthus biomass was characterized by higher content of Al and Mn, whereas higher levels of Fe, Co, and Mo were determined in the reed canary grass biomass. As in the case of the element content, the giant miscanthus was characterized by highest level of Al and Mn uptake, while the highest uptake of Fe, Co, and Mo was exhibited by the reed canary grass. In the group of the analyzed microelements, the giant miscanthus showed the highest the recovery of Mo (47%) followed by Mn (39%), Fe (35%), and Co (15%), and the lowest uptake was determined in the case of Al (5%). In addition to the use of their biomass for the production of renewable energy, energy crops (reed canary grass, giant miscanthus) can be used to recover microelements from municipal sewage sludge. Energy crop biomass can therefore be a potential source of microelements in animal feed. Attention was paid to the mass ratios of Fe:Mn, Fe:Al, Fe:Co, Fe:Mo, Mn:Al, Mn:Co, Mn:Mo, and Co:Mo in the biomass yield of the species used. [ABSTRACT FROM AUTHOR]

Nitrogen (N) mineralized from soil organic matter during the growing season can be an important source of crop-available N. However, accurate estimates for subsurface drip irrigated fields are currently not available. The main objective of the study was to determine seasonal net N mineralization rates in subsurface drip irrigated fields in California's Central Valley. Soil samples were collected regularly from the top 15 cm of eleven commercial fields during the growing season and subsamples were incubated at an optimal moisture content and at field moisture (soil moisture content at the time of sampling). Net N mineralization in field moist soil was on average 45% of the potential N mineralization. When corrected for daily soil temperature at the sites, net N mineralization during a 4-month period from April 15 to August 15 averaged 25.2 kg ha−1 (median = 20.7 kg ha−1), which corresponds to 10 to 20% of the N in the aboveground biomass of the crops grown in these fields. To achieve a high N use efficiency and limit the risk of nitrate leaching to the groundwater, net N mineralization from soil organic matter should be accounted for when planning N fertilizer applications. [ABSTRACT FROM AUTHOR]

A study of biochar/polypropylene composites has been conducted to describe the influence of biochars on the supermolecular structure of PP. The first stage of the work described the influence of carbonization on the properties of carbon fillers (tomato and miscanthus). The biochar was added to the polymer matrix, and the composite samples were manufactured by extrusion and injection molding. The influence of the fillers was investigated using WAXS, hot-stage optical microscopy, PLM microscopy, FTIR and ASTM designation. There were showed the strong influence of the biochar fillers on the properties of polypropylene matrix in composite materials. Obtained composites were characterized by the satisfying properties. [ABSTRACT FROM AUTHOR]

Belowground interactions are crucial in the over-yielding of intercropping systems. However, the effects of belowground interactions on the yields of intercrops in faba bean-maize relay intercropping system are still unclear. In this study, field and pot experiments were conducted, and the biomass, yield, nutrient accumulation and photosynthetic parameters of intercrops were determined to analyze the effects of belowground interactions and relay intercropping. In the field experiments, the yield and biomass of faba bean and maize in the relay intercropping system was significantly increased compared with the monocropping. The relay intercropping promoted the accumulation of nitrogen and phosphorus in faba bean and maize but showed no effect on potassium accumulation. In the pot experiments, no barrier treatment significantly increased the nutrient accumulation of faba bean and maize, nutrient content in soil, photosynthesis, maize, yield, biomass, plant height, 100-grain weight of faba bean and maize. In summary, relay intercropping increased nutrient accumulation, photosynthesis, biomass and yield of crops. The belowground interactions of intercrops could provide good soil fertility conditions for crop growth. The results can provide references for high-yield cultivation of crops and sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

The application of biomass, as an energy resource, depends on four main steps of production, pre-treatment, bio-refinery, and upgrading. This work reviews Machine Learning applications in the biomass production step with focusing on agriculture crops. By investigating numerous related works, it is concluded that there is a considerable reviewing gap in collecting the applications of Machine Learning in crop biomass production. To fill this gap by the current work, the origin of biomass raw materials is explained, and the application of Machine Learning in this section is scrutinized. Then, the kinds and resources of biomass as well as the role of machine learning in these fields are reviewed. Meanwhile, the sustainable production of farming-origin biomass and the effective factors in this issue are explained, and the application of Machine Learning in these areas are surveyed. Summarily, after analysis of numerous papers, it is concluded that Machine Learning and Deep Learning are widely utilized in crop biomass production areas to enhance the crops production quantity, quality, and sustainability, improve the predictions, decrease the costs, and diminish the products losses. According to the statistical analysis, in 19% of the studies conducted about the application of Machine Learning and Deep Learning in crop biomass raw materials, Artificial Neural Network (ANN) algorithm has been applied. Afterward, the Random Forest (RF) and Super Vector Machine (SVM) are the second and third most-utilized algorithms applied in 17% and 15% of studies, respectively. Meanwhile, 26% of studies focused on the applications of Machine Learning and Deep Learning in the sugar crops. At the second and third places, the starchy crops and algae with 23% and 21% received more attention of researchers in the utilization of Machine Learning and Deep Learning techniques. [ABSTRACT FROM AUTHOR]

Energy produced directly from biomass represents an important part of available alternative energy sources. Industrial hemp has potential energy yields that are higher than those of many other energy crops and, as an annual herbaceous crop, hemp fits into existing crop rotations. The total biomass of hemp per hectare is similar to other energy crops, including mostly grown giant miscanthus, poplar, or willow. Industrial hemp is characterized by a short growing cycle, a decreased need for pesticides, and low plant maintenance. The energetic value of hemp depending on agrotechnical factors, such as sowing density and time of harvest, has been assessed in this study. A three-year field experiment was carried out to prove the possibility of using whole plants and separately hemp straw and panicles for energy purposes. C. sativa was sown at eight sowing rates − 5, 10, 15, 20, 30, 40, 50, and 60 kg · ha−1 and harvested at three developmental stages: at the beginning of panicle formation, at full flowering and at the end of seed setting. The optimal harvest time of hemp grown for energetic purposes was demonstrated to be at full flowering and the optimal sowing rate at 30 kg · ha−1 when hemp yielded 14.65 t · ha−1 equals 275.56 GJ · ha−1. [ABSTRACT FROM AUTHOR]

The production of lactic acid, a polylactic acid monomer from energy crop Miscanthus × giganteus lignocellulosic biomass cultivated in Izmir was investigated. Liquid hot water (LHW) pretreatment was carried out at a temperature range of 140–200 °C, pressure 100 to 200 bar and reaction time of 15–45 min at a fixed flow rate of 2 mL/min using D-optimal experimental plan. The optimum conditions were elicited as 140 °C, 100 bar and 45 minutes, yielding the highest reducing sugar content of 77.32 mg/g, whereas 1.25 mg/mL arabinose and 1.35 mg/mL xylose as monomeric sugars. Subsequently, the enzymatic hydrolysis was applied to the solid fraction. The optimum conditions for enzymatic hydrolysis were determined as 5% (w/v) solid/liquid ratio, 20 FPU/mL enzyme loading and 72 hours, revealing the highest amount of reducing sugar as 200 mg/mL. LHW hydrolysate was used as a production medium for lactic acid manufacturing in submerged fermentation by Rhizopus oryzae. The maximum lactic acid content was found to be 6.8 g/L at 24 hours, whereas the lactic acid yield was 0.28 g/L.h. The sequential design of LHW, followed by enzymatic hydrolysis and submerged lactic acid fermentation can be utilized in industry, contributing to the bioeconomy. [ABSTRACT FROM AUTHOR]

To maintain the global temperature, increase below 2°C, efficient bioenergy use is necessary. Many developed countries have successfully adopted biofuel into their energy mix, but sub-Sahara African (SSA), which has a comparative advantage in terms of land, labor, and climatic conditions for energy crops is trailing. Transportation in SSA is petroleum dependent and driven, with diesel fuel being the most used for heavy-duty vehicles, contributing significantly to the greenhouse gas (GHG) emissions in the region. Bioenergy has been identified as one of the energy resources that will play an essential role in reducing GHG emissions. Throughout the SSA region, different energy crops are grown and cashew nuts with shells, in which the waste are used to produce cashew nut shell liquid (CNSL), are cultivated and harvested in an area of 1,157,001–4,704,272 hectares, which is an increase of 406% from 2000 to 2019. As a result, 30,104,678 metric tons of cashew nuts with shell are produced, representing 51% of global production within the years under review, and approximately 6,020,935 metric tons of CNSL agro-industrial waste are generated. The paper discusses cashew nut post-harvest residue suitable for production of CNSL an inedible biodiesel feedstock for diesel engines. It also discusses CNSL extraction procedures, viscosity reduction methods, and fuel characteristics of various blends with additives. The study concluded that utilization of CNSL biodiesel can reduce the dependence of SSA on petroleum diesel while reducing GHG emissions. [ABSTRACT FROM AUTHOR]

Push-pull technology improves agricultural productivity. However, its long-term effect on biomass carbon and soil organic carbon (SOC) is not yet known. The aims of this study were: to assess the effect of push-pull technology on (1) biomass carbon and (2) SOC, considering climatic conditions and the length of time that push-pull had been practiced on a farm; and (3) to establish the relationship between biomass carbon and SOC on farms. Aboveground biomass carbon and SOC were measured on 36 farms in western Kenya, encompassing three contrasting sites (Bondo, Siaya and Vihiga) and six cropping systems (push-pull and five non-push-pull systems). Farms in western Kenya stock between 3.0 ± 0.3 and 4.0 ± 0.4 t C ha−1 in crop biomass and between 24.4 ± 2.1 and 37.0 ± 2.6 t C ha−1 in the soil for those practicing push-pull, and between 1.1 ± 0.3 and 2.1 ± 0.2 t C ha−1 biomass carbon and between 19.2 ± 2.1 and 31.1 ± 1.7 t C ha−1 soil carbon for those without push-pull. There was no correlation between biomass carbon and SOC. Adoption of push-pull offers opportunities to mitigate climate change through carbon sequestration in plants and soils in low-, medium- and high-rainfall environments in both long and short rain seasons. [ABSTRACT FROM AUTHOR]

In South Africa, the consumption of coal for electricity is at the top of the charts for coal consumption in Africa. The continued usage of non-renewable energy sources accounts for ∼50% of the total greenhouse gas accumulation in the atmosphere globally. This study, therefore, aims to identify suitable sites for wind farms within the Maluti-A-Phofung municipality. Data for this study was sourced from climate stations within the MAP and the extant literature for standards and regulations. The Weibull function and ArcGIS 10.6 were used to establish a suitable site for wind farms within the MAP. The results from the study suggested that wind speed and direction in MAP municipality experienced variations but with a steady-state over time. However, based on criteria from other factors the MAP municipality should opt for micro-generators, that is, individual wind turbines per household for clean energy supply. [ABSTRACT FROM AUTHOR]

Artificial lighting systems have tremendously aided the provision of efficient energy for photosynthesis in crop plants but these are seldom fine-tuned to optimally regulate plant growth. Plants are endowed with photoreceptors that enable them to utilise light of different wavelengths as cues for growth and development. These photoreceptors initiate downstream signalling pathways that modulate gene expression which regulates growth and development in the plant. Numerous studies have described these photoreceptors as biochemical switches that can be selectively regulated to control plant growth and development. The rapid advances in our understanding of plant photo-sensory processes, have propelled efforts to extend these findings to the design of plant growth strategies aimed at enhancing plant traits of agronomic importance in crops by manipulating the light environment. Here, we provide an overview of the different known plant photoreceptors and how the quality, quantity or duration of light can affect plant traits such as yield, quality/nutrition, disease/pathogen resistance and flowering; that can enhance the agricultural and/or horticultural value of crops. The objective of the review is to highlight the potential of (and need for) transfer of information gained from laboratory experiments, for optimising photoreceptor activity towards improving specific plant traits, thereby facilitating sustainable and market-oriented crop production in agricultural and horticultural crops along with enhancement in yield and nutrition. [ABSTRACT FROM AUTHOR]

Remote biomass estimation can benefit agricultural practices in several ways, especially larger areas since it does not require local measurements. The advances of the last few decades in machine learning techniques have created new possibilities for estimating aboveground biomass. A pipeline was established from image acquisition to modelling shoot biomass of two wheat cultivars used in Southern Brazil (TBIO Toruk and BRS Parrudo). A UAV was used to acquire multispectral images with high spatial resolution to calculate vegetation indices (VIs). These VIs along with machine learning approaches are used to model the measured biomass of crops in different growth phases. To correlate the wheat images with measured shoot dry biomass, the following regression models were investigated: random forest, support vector regression, and artificial neural networks. An experiment was designed and conducted at the Agriculture Experimental Station of the Federal University of Rio Grande do Sul (EEA/UFRGS) to assess wheat growth. Variability in crop growth was created for all test areas by varying nitrogen availability. To determine shoot biomass, plants were sampled at three different crop growth stages: V6 (stage of six fully developed leaves), three nodes, and flowering. Our results indicate the importance of the radiometric calibration used. Also, the features extracted from images, such as the VIs combined with machine learning models can be used in precision agriculture for predicting the spatial variability of shoot biomass. The best model for Brazilian wheat cultivars was an artificial neural network with R 2 of 0.90, RMSE of 0.83t/ha, and nRMSE of 8.95%. We also found a strong correlation between ground NDVI with image-based NDVI, with an R 2 of 0.84. [ABSTRACT FROM AUTHOR]

An integrated recirculation aquaculture system (RAS) was designed and developed using bacteria, echinoderms (Athyonidium chilensis), and mollusks (Mytilus chilensis) to maintain water quality. Photovoltaic panels were employed to reduce the energy costs of the crop. The evaluation of survival and growth of adults (2-month olds) and juveniles (7-month olds) of Seriola lalandi fish, fed with commercial pellets, was carried out. Different water parameters (temperature, humidity, irradiance, oxygen, pH, ammonium, nitrite, nitrate, etc.) were recorded. The distribution of trophic levels maintained the quality of the water in the system. The photovoltaic panels allowed autonomy of 4 h of disconnection from the electrical network. The weight gain was optimal in adults for the species (initial 1496 g, final 1698 g) and juveniles (initial 24 g, final 588 g). The survival of 100% of adults and 39% of juveniles was documented. The analysis of the fillet helped ascertain its quality for human consumption. This cultivation system depended only on a reservoir to supply water. Operating the system does not require highly specialized personnel and the use of biofilters/photovoltaic panels reduces operating costs. Finally, the production of commercially important marine organisms in efficient and sustainable cultivation systems may help solve global challenges such as the availability of food. [ABSTRACT FROM AUTHOR]

Alfalfa hay that was grown on a field treated with a methyl bromide and chloropicrin pesticide (at a 98/2 weight ratio) resulted in animal sickness, posing a disposal issue for the harvested feed. In consideration of disposal options, emissions and residues from burning treated and untreated alfalfa hay were sampled and analyzed to provide data for an assessment of potential health and environmental effects. Treated alfalfa hay was tested in parallel with untreated alfalfa in a controlled laboratory combustion facility. Results showed that about half of the bromine and chlorine in the treated hay was emitted and the remaining was retained in the ash. The alfalfa hay burned poorly, with modified combustion efficiencies, the ratio of CO2 to CO + CO2, below 0.89. The emission factor for PM2.5 was statistically higher for the untreated versus treated alfalfa but the PAHs were doubled in the treated alfalfa. The treated alfalfa had significantly more emissions of polychorinated dibenzodioxin/dibenzofuran than the untreated alfalfa by a factor of 10, but less polybrominated dibenzodioxin/dibenzofuran. The high Br concentration in the treated alfalfa biomass may have resulted in formation and emission of mixed halogen compounds which were unable to be analyzed for lack of standards. Comparison of volatile organic compound emissions were unremarkable with the exception of MeBr where emissions from the treated alfalfa were over 300 times higher than the untreated biomass. The potential complications due to emissions and permitting of an open burn or contained incinerator left options for landfilling and feedstock blending for handling the treated alfalfa. Implications: This paper illustrates the issues agricultural managers must deal with concerning the combustive disposal of contaminated crops. A method is presented whereby combustion of contaminated crops can be assessed for their suitability for disposal by open air or enclosed burning. [ABSTRACT FROM AUTHOR]

With increasing annual global coffee consumption, the amount of spent coffee grounds (SCGs) increases. Direct application of SCGs in large agricultural fields can potentially improve soil and control weeds in an environmentally safe manner. However, except for composting, the use of SCGs during cropping has not been implemented thus far because of inhibitory effects on crop growth observed in pot-based studies. We evaluated the effect of a top dressing approach to direct SCG application on crop biomass, soil improvement, and weed control, through double cropping field experiments using wheat and soybean. The field experiments were conducted over six successive cropping seasons in an upland field converted from paddy, and crop and weed biomass as well as soil total carbon and nitrogen were investigated. To avoid growth inhibition, the SCGs were surface broadcasted after crop germination to mimic living mulch. The soil total carbon and nitrogen contents increased significantly under an SCG concentration of 5 kg m−2 or more, approximately 20 months after the first application, whereas SCG application did not significantly affect crop yield except for the first cropping of wheat. In addition, the 10 kg m−2 SCG application reduced the weed biomass by 50% or more during cropping, except for the wheat cropping in the second year. We concluded that top dressing with SCGs after crop germination is an efficient method for sustainable agricultural production, although further detailed studies of SCGs' effect on the crop growth and soil characteristics are required. [ABSTRACT FROM AUTHOR]

Recent laboratory evidence suggests that the intrinsic behavior of molecular water in soil is altered by turbulent-flow conditioning (CTap) of mineralized irrigation water (Tap). This 9-yr (2009 to 2017), irrigated, outdoor, cropped pot study evaluated the effect of Tap and CTap irrigation water on soil leachate chemistry, nutrient availability, and aboveground crop biomass yield and nutrient uptake. CTap increased cumulative mass losses of: nitrate nitrogen 2.5-fold; manganese 2-fold; potassium (K) 1.6-fold; magnesium (Mg), dissolved organic carbon, and ammonium nitrogen (NH4-N) an average 1.2-fold; and increased the mean electrical conductivity of leachate 1.2-fold. In both the current and a previous laboratory study (see Part 1), K, NH4-N, and Mg were leachate components most consistently selected by multivariate analysis as best discriminating between water treatments. The evidence also suggests that CTap increased mean available soil zinc (Zn) 2.4-fold, copper, K, and soil phosphorus an average 1.4-fold, sodium and iron (Fe) 1.2-fold, and decreased soil total carbon, TC (4%), total inorganic carbon (8%) and Mg (9%) relative to the Tap. In addition, CTap increased average crop biomass element concentrations: Zn, Fe, and aluminum an average 1.3-fold; total nitrogen, calcium, K, and sulfur 1.1-fold; and decreased TC (2%) relative to Tap. If the capacity of this simple device to increase soil cation leaching can be confirmed in broader applications, it could potentially provide an economical means of increasing the availability of nutrients in soils irrigated with conditioned water and managing or remediating degraded, salt-affected soils. [ABSTRACT FROM AUTHOR]

Cover crop adoption in conventional no-tillage corn/soybean production systems has been limited due to the lack of specific information regarding the impact of cover crops on cash crop performance. Within a no-till small grain/cover crop-corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation in eastern South Dakota, we evaluated the impact of fall-planted forage oat (Avena sativa L.), hairy vetch (Vicia villosa Roth), winter canola (Brassica napus L.), and a combination of all three compared to a no cover crop treatment on soil nutrient dynamics, biomass, nutrient uptake, and grain yield of the immediatelyfollowing corn crop. At site-year 1, where cover crop growth was most consistent, corn yield was significantly higher with oat, vetch, and a combination of all three cover crops compared to the no cover crop treatment. At site-year 2, corn yields were equivalent among treatments except the combination treatment which was significantly lower. At site-year 3, corn yields in the canola and oat treatments were equivalent to no cover crop, while corn yields with vetch and the combination treatments were lower. Corn biomass and nutrient uptake responded to treatments similarly to corn yields. For site-years 1 and 2, some cover crop treatments resulted in modest, but significant increases in soil N during spring. For site-year 3, the combination treatment immobilized N during the corn vegetative growth phase but released N during the reproductive phase. Cover crop treatments had little effect on plant-available soil P. However, soybean yields two years following cover crop treatments were higher for all three site years with cover crops compared to no cover crop, with this difference significant in two of the three site-years. Immediate effects of cover crops on the following cash crop under no-till were variable and depend on both fall and spring cover crop biomass, which in turn are dependent on the amount and timing of precipitation and temperature patterns. Cover crops in no-till systems may produce more consistent but possibly delayed benefits by boosting yields of cash crops in later years as cover crop residues decompose. [ABSTRACT FROM AUTHOR]

Lightning location is a significant issue in the protection of transmission lines, renewable energy sources, and electrical equipment. In this article, a new technique for the determination of lightning striking points is been proposed. This method is depending on measured values of lightning-induced voltage obtained from distribution power lines in the vicinity of the lightning channel. The proposed method considers lightning location as well as lightning current wave shape at the channel base. It was validated using a number of measured return stroke currents, and the outcomes are debated accordingly. All electromagnetic field components were taken into consideration in the proposed method, and lightning current wave shape was determined in contrast with the other, widely used methods. Evaluated lightning current wave shapes, based on local measured data, can be used to examine and improve existing protection schemes in renewable energy generation farms, transmission lines, and other power sites. Moreover, lightning maps and ground flash density can be obtained from the evaluated lighting location data to be used in lightning risk assessment studies. [ABSTRACT FROM AUTHOR]