Nutrient Yield Research Articles

Influence of yellow gypsum on nutrient uptake and yield of groundnut in different acid soils of Southern India

Yellow gypsum (YG), a synthetic product from Linz-Donawitz slag containing high iron (Fe) (5.41%), zinc (Zn) (0.37%) and silicon (Si) (3.41%) can be used as a source of these nutrients along with calcium (Ca) and sulphur (S) for groundnut production. Three field experiments were conducted to know the effect of different rates (500 and 625 kg YG ha−1) and time of application (basal alone and basal + split) of YG on growth, yield and economic returns of groundnut, and micronutrient and Si availability and their uptake in comparison with basal application of 500 kg natural gypsum (NG) ha−1. Basal alone and basal + split application of YG significantly increased the growth, yield and economic returns of groundnut. Further, it increased the soil pH, availability of micronutrients, Si and their uptake by haulm and kernel of groundnut over NG. Irrespective of the location, YG application recorded higher plant available nutrient (PAN) coefficient of micronutrients, while NG application recorded higher PAN recovery coefficient of Si. Basal + split application of YG resulted in better growth and yield of groundnut than basal application of YG. In conclusion, YG can be a potential alternative for NG as a source of Fe, Zn and Si along with Ca and S for groundnut production.

Assessment of BMPs by Estimating Hydrologic and Water Quality Outputs Using SWAT in Yazoo River Watershed

Water quality is a global concern; it is due to point and non-point source pollution. Non-point sources for pollution are mainly runoff from Agricultural and forest. To decrease nutrient inputs, management practices are implemented. Using Soil and Water Assessment Tool, water quality parameters can be quantified. Yazoo River Watershed is the largest watershed in Mississippi, which have impact on surface water quality due to large scale agriculture and forest lands. Model has been calibrated and validated for streamflow, sediment, Total Nitrogen (TN), Total Phosphorus (TP) for the USGS gauge stations in the watershed. Model efficiency was assessed with Coefficient of Determination (R2) and Nash-Sutcliffe Efficiency index (NSE). Best Management Practices (BMPs) were implemented throughout the watershed to simulate the impact of BMPs on streamflow, sediment, and nutrient yields. Vegetative Filter Strips (VFS), Riparian Buffer, combination of VFS and Riparian buffer and Cover Crops (CC) were tested for assessing the effective BMP in improving water quality. VFS, Riparian buffer and both (VFS + riparian) have no effect on streamflow, but they were able to decrease sediment, TN, and TP yields. Scenario with both VFS and Riparian buffer had the highest reduction capability as per varying width (5, 10, 15, and 20 m). For CC, Rye grass, Winter Barley and Winter Wheat (WW) were used, of which Rye grass had highest, 5.3% reduction in streamflow. WW has the highest Total Nitrogen reduction that is of 25.4%. CC also has significant reduction ranged between 10% to 11% for TP. This research would assist the Agricultural community to apply appropriate Management practices to improve water quality.

Response of Fungal Sub-Communities in a Maize-Wheat Rotation Field Subjected to Long-Term Conservation Tillage Management.

Conservation tillage is an advanced agricultural technology that seeks to minimize soil disturbance by reducing, or even eliminating tillage. Straw or stubble mulching in conservation tillage systems help to increase crop yield, maintain biodiversity and increase levels of exogenous nutrients, all of which may influence the structure of fungal communities in the soil. Currently, however, the assembly processes and co-occurrence patterns of fungal sub-communities remain unknown. In this paper, we investigated the effects of no-tillage and straw mulching on the composition, assembly process, and co-occurrence patterns of soil fungal sub-communities in a long-term experimental plot (15 years). The results revealed that combine straw mulching with no-tillage significantly increased the richness of fungi but not their diversity. Differential abundance analysis and principal component analysis (PCA) indicated that tillage management had a greater effect on the fungal communities of abundant and intermediate taxa than on the rare taxa. Available phosphorus (AP) and total nitrogen (TN) were the major determinants of fungal sub-communities in NT treatment. The abundant fungal sub-communities were assembled by deterministic processes under medium strength selection, while strong conservation tillage strength shifts the abundant sub-community assembly process from deterministic to stochastic. Overall, the investigation of the ecological network indicated that no-tillage and straw mulching practices decreased the complexity of the abundant and intermediate fungal networks, while not significantly influencing rare fungal networks. These findings refine our knowledge of the response of fungal sub-communities to conservation tillage management techniques and provide new insights into understanding fungal sub-community assembly.

Nutritional Yield and Composition of Spiny and Spineless Varieties of Safflower (Carthamus tinctorius L.) Forage Harvested at Four Phenological Stages

Background: Delaying harvesting in spineless safflower (Carthamus tinctorius L.) can increase dry matter (DM) yield, maintaining an acceptable nutritional composition. Objective: The objective of this study was to compare the forage potential of spineless safflower cultivars with that of spiny cultivars harvested in four phenological stages. Methods: The research was carried out during the 2017-2018 and 2018-2019 cycles in Matamoros, Coahuila, Mexico. Two spineless (CD868 and Selkino) and two spiny (Gila and Guayalejo) cultivars were evaluated. The phenological stages were: beginning of capitulum formation (E50), capitulum clearly separated from the younger leaves (E55), distinguishable medium and intermediate external bracts (E59), and beginning of flowering (E61). A randomized complete blocks design was used with four replications in a 4 × 4 factorial arrangement of treatments. Results: No interactions were found between phenological stages and cultivars. The spineless cultivars showed better or equal nutritional composition when compared to spiny cultivars but with better forage in E50. Yields of DM and nutrients increased when harvesting was delayed from E50 to E61, maintaining an acceptable nutritional composition. The highest yields of DM (10816 kg ha-1), crude protein (CP) (2071 kg ha-1), net energy for lactation (NEL) (52978 MJ ha-1 DM), and digestible DM (6350 kg ha-1) occurred in E61. Conclusion: Spineless cultivars harvested at stage E61 increased the forage potential with regards to the spiny cultivars harvested in E55, which did not have fully developed spines, due to their higher yields of DM (58%), CP (29%), NEL (39%), and digestible DM (41%).

Co-application of Phosphorus and Sulfur Improve Yield, Quality, and Nutrients Uptake in Nicotiana tabaccum L.

A field experiment was carried out to evaluate the interactive effect of phosphorus (0, 30, 60, and 90 kg P2O5 ha-1) and sulfur (0, 15, 30, and 45 kg ha-1) on yield, quality, and uptake of nutrients by tobacco (Nicotiana tabaccum L.). The experiment was organized in a two-factorial randomized complete block design with three replications at Tobacco Research Station, Mardan, Pakistan in 2017-2018. Application of 90 kg P2O5 ha-1 improved tobacco leaf area (24.2%), green leaf weight (44.5%), cured leaf weight (44.7%), grade index (18.3%), nicotine (35.8%), sugar (12%), and P (24.5%) contents but decreased S content (35.3%) over control phosphorus plots. Similarly, application of 45 kg S ha-1 optimized leaf area (13.6%), grade index (12%), nicotine (15%), P (5.9%), and S (96%) contents over control sulfur plots. Interactively, P application antagonized leaf S content. However, it did not show any adverse effect on other agronomic and quality parameter. Both P and S application decrease leaf chloride content by 43.5% and 21.4%, respectively. Thus, 90 kg P2O5 ha-1 along with 45 kg S ha-1 is recommended for obtaining optimum yield of good quality tobacco crop.

Influence of Magnesium in Combination with Organics on the Yield and Uptake of Nutrients by Cotton (Gossypium hirsutum L.) Crop in Typic ustropept

A field experiment was conducted to evaluate the effects of magnesium and organic manures on yield and nutrient uptake of cotton (Gossypium hirsutum L.) between 28th Aug 2019 and Jan 2020 in a farmer’s field located at Achchandavilthan village of Srivillipudhur block, Virudhunager district, Tamil nadu. This experiment comprised of fifteen treatment with three replication involving magnesium in combination with organics.The results revealed that the application of MgSO4 at the rate of 50 kg ha-1 along with 250 kg vermicompost for 30 days (1:5 ratio) at critical stages of crop growth along with the Soil Test Crop Response (STCR) based N,P2O5 and K2O registered maximum nutrient uptake of major nutrients Nitrogen (14.25, 23.60 and 43.50 kg ha-1), Phosphorus (6.25,7.80 and 10.34 kg ha-1), Potassium (20.35, 34.50 and 47.45 kg ha-1) 40,70 DAS and harvest stage, secondary nutrient like Calcium(20.54, 33.21 and 69.21 kg ha-1), Magnesium (4.65, 5.75 and 10.50 kg ha-1) 40, 70 Day after sowing (DAS) and harvest stage and micro nutrient Iron (1185.6, 1975.6 and 4865.2 325.80g ha-1), Manganese (380.5, 530.2 and 792.3 325.80 ), Zinc (90.65, 155.72 and 325.60 325.80 ), and Cupper (90.62, 155.70 and 325.80 325.80 ) 40, 70 DAS and harvest stage of crop growth.

SALINE WATER AND NITROGEN FERTILIZATION ON LEAF COMPOSITION AND YIELD OF CORN

ABSTRACT Absence of drainage associated with high evapotranspiration and irregular precipitations contributes to the accumulation of salts in the soil, reducing nutrient absorption and yield. Nutritional management is important for the crop to express its maximum production potential, and nitrogen is the macronutrient most required by the corn crop. The objective of this study was to evaluate yield and leaf contents in corn under different nitrogen fertilization recommendations and salt stress. The experiment was conducted from June to September 2019, at the University of International Integration of Afro-Brazilian Lusophony in Redenção-CE, Brazil. The experimental design used was completely randomized, in a 2 x 3 factorial arrangement, with 6 replicates, with two levels of electrical conductivity (0.3 dS m-1 and 3.0 dS m-1) and three nitrogen fertilization recommendations (0, 50 and 100% of the recommendation). The variables analyzed were unhusked ear weight, husked ear weight, yield and leaf contents of N, P, K, Ca, Mg and Na. Irrigation with saline water (3.0 dS m-1) reduces the unhusked ear weight, husked ear weight and yield. Nitrogen fertilization recommendations of 50% and 100% promoted higher values of unhusked ear weight, husked ear weight and leaf N contents, but reduced leaf P contents. The 50% and 100% recommendations promote higher yield values for the two levels of electrical conductivity studied (0.3 and 3.0 dS m-1). The 50% and 100% recommendations associated with saline water irrigation increased the leaf contents of K, Na, Mg and Ca.

Microalgae growth and diversity in anaerobic digestate compared to synthetic media

Economizing microalgal cultivation is a considerable milestone targeted by efforts put into microalgal biorefineries. In light of that, the present study was aimed to explore the potential of using anaerobic liquid digestate (ALD) as culture media to grow microalgae and compared it with three different synthetic media (i.e., N8, BBM, and M8) in terms of biomass yield, fatty acid composition, and nutrient utilization/recovery. Moreover, a mixed culture of wild-type microalgae was employed in this study owing to the ability of mixed cultures to survive extreme conditions, eliminating the risk of losing the culture easily, as it mostly happens with pure cultures. The highest nutrient yield coefficients were achieved when the mixed microalgae culture was cultivated in ALD, where the yield coefficient for nitrogen (YN) and yield coefficient for phosphorus (YP) were 10.7 mg biomass mg-1 N and 98 mg biomass mg-1 P, respectively. The highest lipid content (34%) and the highest concentrations of C16:0 (114 mg L-1) and C18:0 (60.9 mg L-1) were also recorded when the mixed microalgae culture was cultivated in ALD. Furthermore, the polyunsaturated fatty acids (PUFA) content also increased significantly in ALD, a beneficial phenomenon as PUFAs in microalgae allow them to adapt more effectively to extreme conditions. Based on the microbial community analysis performed using the multi-marker metabarcoding approach, Diphylleia rotans, Synechocystis PCC-6803, Cyanobium gracile PCC 6307, and Chlorella sorokiniana were identified as the most abundant species in the ALD growth. Overall, based on the findings of the present study, ALD could be used as a promising cultivation medium for microalgae, offering a process integration approach to combine anaerobic digestion and algae cultivation as an effective way to simultaneously treat the high-strength dark-colored ALD and valorize it into profitable byproducts.

Managing fisheries for maximum nutrient yield.

Wild‐caught fish are a bioavailable source of nutritious food that, if managed strategically, could enhance diet quality for billions of people. However, optimising nutrient production from the sea has not been a priority, hindering development of nutrition‐sensitive policies. With fisheries management increasingly effective at rebuilding stocks and regulating sustainable fishing, we can now begin to integrate nutritional outcomes within existing management frameworks. Here, we develop a conceptual foundation for managing fisheries for multispecies Maximum Nutrient Yield (mMNY). We empirically test our approach using size‐based models of North Sea and Baltic Sea fisheries and show that mMNY is predicted by the relative contribution of nutritious species to total catch and their vulnerability to fishing, leading to trade‐offs between catch and specific nutrients. Simulated nutrient yield curves suggest that vitamin D, which is deficient in Northern European diets, was underfished at fishing levels that returned maximum catch weights. Analysis of global catch data shows there is scope for nutrient yields from most of the world's marine fisheries to be enhanced through nutrient‐sensitive fisheries management. With nutrient composition data now widely available, we expect our mMNY framework to motivate development of nutrient‐based reference points in specific contexts, such as data‐limited fisheries. Managing for mMNY alongside policies that promote access to fish could help close nutrient gaps for coastal populations, maximising the contribution of wild‐caught fish to global food and nutrition security.

Evaluation of the Impact of Best Management Practices on Streamflow, Sediment and Nutrient Yield at Field and Watershed Scales

Evaluating Best Management Practices (BMPs) in watersheds using hydrologic and water quality models can help to establish an effective watershed water management. Soil and Water Assessment Tool (SWAT) was applied to Big Sunflower River Watershed (BSRW) and the Stovall Sherard Watershed (SSW) to evaluate BMP’s impact at watershed and field scale watersheds respectively. SWAT was calibrated and validated for streamflow, sediment yield, total nitrogen (TN), and total phosphorous (TP) at outlets of three sub-basins of the BSRW, and within the SSW. BMP scenarios of check-dam, tail water pond, vegetative filter strips (VFS), nutrient management, and tillage management were evaluated for their efficacy in reducing streamflow, sediment yield, and nutrient loads at field and watershed scales. The VFS was determined as the most effective BMP in decreasing sediment yield, TN, and TP at both field and watershed scales. At field scale, reduction of sediment yield, TN, and TP by VFS ranged from 8 to 12%, 71% to 98%, and 72% to 99% respectively and at watershed scale, reduction of sediment yield, TN, and TP by VFS ranged from 12 to 38%, 29% to 87%, and 42% to 99% respectively. The application of conservation and zero tillage operation showed reduction in sediment yield by 1% to 2% respectively but increased TN and TP by 2% to 25% at field and watershed scale watersheds. This study will help in managing water at field and watershed scale watersheds regarding BMPs selection and implementation.Graphical

Ultrahigh recovery rate of nitrate from synthetic wastewater by Chlorella-based photo-fermentation with optimal light-emitting diode illumination: From laboratory to pilot plant

To achieve ultrahigh recovery rate of nitrate from synthetic wastewater by Chlorella pyrenoidosa-based photo-fermentation, light-emitting diode (LED) spectrum was firstly evaluated in 5-L glass photo-fermenter with surrounding LED panels. Results showed that warm white LED was favorable to improve biomass yield and recovery rate of nutrients than mixed white LED. When scaling up from laboratory (50-L, 500-L) to pilot scale photo-fermenter with inner LED panels, the maximum recovery rates of NO3- (5.77 g L-1 d-1) and PO43- (0.44 g L-1 d-1) were achieved in 10,000-L photo-fermenter, along with high productivity of biomass (11.06 g L-1 d-1), protein (3.95 g L-1 d-1) and lipids (3.79 g L-1 d-1), respectively. This study demonstrated that photo-fermenter with inner warm white LED illumination is a superhigh-efficient system for nitrate and phosphate recovery with algal biomass coproduction, providing a promising application in pilot demonstration of wastewater bioremediation and facilitating novel facility development for green manufacturing.

Conservation Agriculture Affects Grain and Nutrient Yields of Maize (Zea Mays L.) and Can Impact Food and Nutrition Security in Sub-Saharan Africa.

Maize is a major staple and plays an essential role in food and nutrition security in Sub-Saharan Africa (SSA). Conservation agriculture (CA), a climate-smart agriculture practise based on minimum soil disturbance, crop residue retention, and crop diversification, has been widely advocated but without extensive research on the impact it may have on maize nutrient composition, and food and nutrition security. This study assessed the grain yield, macro- and micronutrient mineral content, and nutrient yield of eight maize varieties grown in Malawi, and how these are affected by CA practises over two seasons. The minerals were analysed by inductively coupled plasma (ICP) coupled to optical emission spectroscopy (OES) and to mass spectroscopy (MS). Grain yield and Se content differed among the varieties, while C, N, Fe, K, Mg, Mn, P, and Zn were similar. The local variety Kanjerenjere showed lowest grain and nutrient yields. The open-pollinated varieties (OPVs) concentrated more minerals than the F1 hybrids, but the latter showed higher yields for both grain and nutrients. Typical consumption of the eight maize varieties could fully meet the protein and Mg dietary reference intake (DRIs) of Malawian children (1–3 years), as well as Mg and Mn needs of adult women (19–50 years), but their contribution to dietary requirements was low for Fe (39–41%) and K (13–21%). The trials showed that CA increased grain yield (1.2- to 1.8-fold) and Se content (1.1- to 1.7-fold), but that it had no effect on C, K, Mg, P, and Zn, and that N (1.1- to 1.2-fold), Mn (1.1- to 1.8-fold), and Fe (1.3- to 3.4-fold) were reduced. The high increase in grain yield under CA treatments resulted in increased yields of protein and Se, no effect on the yields of K, Mg, Mn, P, Zn, and reduced Fe yield. Conservation agriculture could contribute in reducing the risk of Se deficiency in Malawian women and children but exacerbates the risk of Fe deficiency. A combination of strategies will be needed to mitigate some of the foreseen effects of climate change on agriculture, and food and nutrition security, and improve nutrient intake.

Influence of Different Levels of Drip Fertigation and Mulching on Growth, Yield, Water Productivity and Nutrient Uptake of Pigeonpea (Cajanus cajan L.)

Background: Pigeonpea is second most important pulse crop grown after chickpea in India. Pigeonpea is versatile crop can be grown in vast agro climatic condition with low inputs. However, the yield is very low as compared to the potential yield as grown in rainfed condition, the drip fertigation and mulching can increase resource use efficiency. Both these techniques are resource saving and realized maximum yield by reducing the nutrient and water losses as compared to conventional practices. Methods: The experiment was laid out in factorial complete randomized block design and replicated thrice. The experiment consisted of two levels of irrigation (0.50 CPE and 0.75 CPE) as one factor and three fertility levels (100% RDF, 75% RDF and 50% RDF) as second factor and two levels of mulching (without mulching and with plastic mulching 25 micron) as third factor. Result: The results revealed that higher level of irrigation (0.75 CPE) with 100 per cent RDF and with plastic mulching recorded significantly higher growth rate, seed yield and uptake of nutrients by the pigeonpea crop.

Nitrogen and phosphorus removal by fishing in a large freshwater lake (Lake Balaton, Hungary)

ABSTRACT Fish biomass can serve as a large temporary sink of limiting nutrients, and thus fishing may represent an important anthropogenic nutrient efflux from aquatic ecosystems. However, the significance of this type of nutrient removal has rarely been evaluated for freshwater lakes. The aim of this study was to reveal how fishing contributed to the nutrient output from Lake Balaton (Hungary), the largest lake in Central Europe. The results show that net fish removal (the difference between the removed and stocked fish biomass) returned to land on average (standard deviation) 3.1 (0.3) tonnes of phosphorus (P) and 10.2 (1.1) tonnes of nitrogen (N) per year from Lake Balaton between 2017 and 2019, which is equivalent to a removal rate of 0.05 (0) kg ha−1 yr−1 P and 0.17 (0.02) kg ha−1 yr−1 N. These rates corresponded to 7.5% (1.5%) of the annual external P and 1.4% (0.6%) of the annual N loads from the inflowing watercourses. These findings suggest that fish harvest was moderately effective at offsetting external loading during the observed period. To mitigate the ongoing within-lake nutrient accumulation, more intensive selective fishing should be promoted in Lake Balaton, along with reconsideration of regulations on fishing practices.

Optimizing land use systems of an agricultural watershed in China to meet ecological and economic requirements for future sustainability

The contradiction between economic development and water pollution is ever so obvious in most agricultural watersheds in China. The continuous popularization of commercial crops in hills, especially tea, has intensified water eutrophication, which has attracted close attention of the Chinese government. Under this circumstance, local authorities have proposed the returning of tea plantations to forests, which would distinctly inhibit the development of rural economics. Hence, we employed a calibrated SWAT model to determine the total nitrogen/total phosphorus (TN/TP) loads in the reservoir, nutrient contribution of each land use type, and landscape pattern in a representative agricultural watershed. Aimed at the synchronous development of the economy and environment, this research study investigated the correlation between landscape pattern and nutrient output to accordingly propose alternative management strategies based on the correlation and actual watershed situation. Correlation analysis suggested that the landscape pattern prominently affects nutrient output in farmlands, tea plantations, orchards, and grasslands, and that the impact varies with the land use types and landscape parameters. Furthermore, a stepwise multiple regression model revealed that the landscape pattern could effectively predict nutrient output in farmlands, tea plantations, orchards, and grasslands. The aggregation index ( AI ) ( R 2 = 0.996, p < 0.05) and contiguity index ( CONTIG ) ( R 2 = 0.963, p < 0.01) are the primary landscape drivers for the export of TN and TP in farmlands, respectively, and the percentage of landscape ( PLAND ) is the key driver for TN loss in tea plantations ( R 2 = 0.841, p < 0.05). The fractal dimension index ( FRAC ) is the pivotal driver both for TN ( R 2 = 0.969, p < 0.01) and TP ( R 2 = 0.845, p < 0.05) export from orchards. According to the actual watershed situation and the relationship between nutrient output and landscape pattern, six alternative management strategies were performed: planting tea along contour lines (S1), constructing filter strips downstream tea plantations and orchards (S2), changing the shape of orchards (S3), controlling the nutrient emissions of residential areas (S4), returning farmlands to forests (S5), and a combination of S1-S5 (S6). All these measures are superior to the current government strategy (returning tea plantations around reservoirs to forests) in terms of both cutting down reservoir nutrient loads and reducing economic loss. Among them, S6 is the optimal strategy; using this, TN and TP loads are expected to be reduced by 51.64% and 58.96%, respectively, compared with those in 2019, and the economic loss will be far lower than that upon implementation of the current government strategy. This study has provided detailed suggestions for watersheds plagued by the contradiction between agricultural economic development and water pollution. • Correlation between TN/TP output and landscape pattern indices varies with land use types. • Optimal land management strategies were proposed based on landscape pattern and watershed sustainable development. • Optimal strategy can reduce reservoir TN/TP loads by 50% with much lower economic loss than current government strategy.

Effect of potassium and zinc application on crop yield and uptake of nutrients in green gram (Vigna radiata L.) under coarse textured soils

The aim of present study was to find out the optimum dose and application effect of potassium (K) and zinc (Zn) on green gram yield, nodulation, uptake and its build-up/depletion in soil to overcome the production of pulses in Haryana. A series of field experiments were conducted during kharif season from 2018 to 2020 at the Regional Research Station, Chaudhary Charan Singh Haryana Agricultural University (CCSHAU), Bawal, Haryana. The experiment was laid out in a split plot design with four levels of K (0, 10, 20 and 30 kg K2O ha−1) in main plot and Zn (0, 12.5, 25 and 37.5 kg ZnSO4 ha−1) in sub-plot with three replications. The results revealed that application of K significantly affected the yield of green gram up to 20 kg K2O ha−1 whereas Zn application significantly affected the yield of green gram up to 25 kg ZnSO4 ha−1. The interaction between K and Zn was non-significant. The nodules fresh weight and number of nodules per plant increased significantly with the application K whereas, these parameters increased with the application of Zn but results were not significant. The K and Zn application significantly increased their content and uptake in seed and straw of green gram. The available K in soil was influenced by K application but was found to be significant with 20 and 30 kg K2O ha−1. The DTPA extractable Zn content in soil after harvest of crop was also significantly higher with the application of zinc sulphate.

ДИСТАНЦИОННОЕ ЗОНДИРОВАНИЕ ПАСТБИЩ ДЛЯ ПРОГНОЗИРОВАНИЯ ПРОДУКТИВНОСТИ ОВЕЦ

This article discusses the prospects for the use and rapid development of modern satellite systems and observation technologies in pasture farming. The main possibilities of constructing a predictive model for planning the productivity of pasture herbage on the basis of multivariate analysis of remote sensing are presented. The obtained data are used to build a technological map of animal grazing. Currently, the data obtained as a result of satellite observation and associated technologies are increasingly used in tasks related to obtaining reliable objective information about the state of agricultural land and the possibility of their industrial use. To solve the set tasks, specialized information systems and models of various levels of predicting the productivity of the land used and the productivity of pasture animals are rapidly being developed and implemented. As objectively observable data on the current state of pastures in our studies, we used multispectral images of the Copernicus Sentinel-2 Earth remote sensing satellite of the European Space Agency (ESA). The data obtained made it possible to establish the relationship between the productivity of rangelands and the vegetation index obtained by the remote method and verified by the contact method during field trials. Studies of the chemical composition and nutritional value of forage grazing plants made it possible to assess the yield of nutrients and energy from 1 m2. According to the results of accounting for the live weight of the controlled animals, it was found that the live weight of sheep grazed on pasture No. 1 statistically significantly exceeded this indicator by 6.2% in analogues that were grazed on pasture No. 2. Based on the results obtained, recommendations were made to substantiate the periods of optimal use of pasture areas, based on the use of digital methods of remote monitoring.

The potential of new bio-decomposers for composting sugarcane waste

The process of composting sugarcane residue by new bio-decomposer consortium formula contain specific microbes with different functions such as ligninolytic and cellulolytic microbes can improve the quality of agricultural waste. These bacteria have the potential to enhance sugarcane litter and other sugarcane residues. The fermentation process led to the C/N ratio of compost serves as a reference for the effectiveness of the decomposition process by bacteria. The research was designed as an alternative to producing organic fertilizers by using four bio-decomposer consortium formulas as ISAFCRI collection and EM4 as commercial bio-decomposer. The physicochemical characterization of 5 composts, including the C/N ratio of compost, is below 12-17, macroelements N, P, K available in compost are relatively high compared to the minimum requirement of SNI. The compost 5 with EM4 bio-decomposer appeared to have lower nutrient yields than compost using other decomposers. Compost 1 with formula one, which contains a consortium of lignocellulolytic bacteria, has excellent potential to be developed as a new bio-decomposer formula for processing sugarcane waste. The pilot test has shown that varieties of composts and organic fertilizers can be made from a mixture of sugarcane residue.

Environmental Management of Fish Cage Aquaculture

Most modern fish culture involves the intensive input of nutrients in the form of feed, yet only a small proportion of these nutrients is converted into the target product; they can be largely lost to bacterial degradation. However, when compared with other livestock production systems, aquaculture has better feed conversion efficiency and feed conversion ratios (FCRs) are continuing to improve. High levels of nutrients from fish cages may cause eutrophication and thus may affect fisheries adversely, but on the contrary, the additional nutrients from the feed may have a beneficial effect, boosting natural productivity including fisheries. The important components of fish farming waste comprise nutrients (dissolved and particulate) resulting from the metabolism of fish food, uneaten food, escapees of farmed fish affecting the genetic diversity of wild fish populations and chemical residues of disease or parasitic therapeutant treatments. Potential management measures to mitigate environmental impacts include public and private sector approaches. The public sector approaches include appropriate and specific aquaculture policies, strategies, regulations, legislation, and management plans, adoption and implementation of the FAO Code of Conduct for Responsible Fisheries (CCRF) and Ecosystem Approach to Aquaculture (EAA) strategies for planning, management, monitoring, and control. Zoning for aquaculture space is to be based on the allocation of aquafarms on suitable areas, appropriate evaluation of carrying capacity of the ecosystem, planning and management for disease prevention and treatment and environmental control. Appropriate control of farm permits, licences, and registration by the state is necessary to monitor and control aquaculture development. The private sector approaches include improved feed formulation and feeding strategies to reduce the feed conversion ratio and nutrient losses, the use of Integrated Multi-trophic Aquaculture (IMTA) to utilise nutrient outputs from intensive aquaculture and thus regular environmental monitoring is the key to ensure that impacts remain within acceptable limits.

Climate change impact on water quality in the integrated Mahabad Dam watershed-reservoir system

Climate change, besides global warming, is expected to intensify the hydrological cycle, which can impact watershed nutrient yields and affect water quality in the receiving water bodies. The Mahabad Dam Reservoir in northwest Iran is a eutrophic reservoir due to excessive watershed nutrient input, which could be exacerbated due to climate change. In this regard, a holistic approach was employed by linking a climate model (CanESM2), watershed-scale model (SWAT), and reservoir water quality model (CE-QUAL-W2). The triple model investigates the cumulative climate change effects on hydrological parameters, watershed yields, and the reservoir’s water quality. The SDSM model downscaled the output of the climate model under moderate (RCP4.5) and extreme (RCP8.5) scenarios for the periods of 2021–2040 and 2041–2060. The impact of future climate conditions was investigated on the watershed runoff and total phosphorus (TP) load, and consequently, water quality status in the dam’s reservoir. The results of comparing future conditions (2021–2060) with observed present values under moderate to extreme climate scenarios showed a 4–7% temperature increase and a 6–11% precipitation decrease. Moreover, the SWAT model showed a 9–16% decline in streamflow and a 12–18% decline in the watershed TP load for the same comparative period. Finally, CE-QUAL-W2 model results showed a 3–8% increase in the reservoir water temperature and a 10–16% increase in TP concentration. It indicates that climate change would intensify the thermal stratification and eutrophication level in the reservoir, especially during the year’s warm months. This finding specifies an alarming condition that demands serious preventive and corrective measures.