Crop Production Quality Research Articles

Crop Management Systems: A New Generation of Agricultural Security with Innovations

Crop management deals with aspects of volume and quality of crop production and has, in turn, further implications. As many as over nine billion people are likely to be living on the Earth by 2050, and they will probably have some highly efficient as well as sustainable practices in place. This paper focuses on the characteristics of crop management systems, including the components and technologies that mark a system. The available digital tools and their contribution to precision agriculture toward achieving sustainable milieu approaches are carefully queued together to establish that they effectively provide an integrated approach with productivity at low cost and environmentally stressed conditions. Keywords: Crop management, sustainable agriculture, digital tools, precision farming, yield optimization, agricultural technology.

An assessment of the supply chain management for agricultural products in Cambodia

The primary objective of this research is to examine the supply chain management of cashew nuts, mangoes, and cassava in Cambodia. The findings indicate that Cambodian farmers predominantly rely on traditional methods for crop cultivation. A significant issue is their lack of adequate knowledge regarding the assessment and utilization of land quality, which results in both the quantity and quality of their crop yields falling short of acceptable standards. Consequently, this deficiency adversely affects the market prices of their produce. To address this knowledge gap, it is essential for relevant institutions, particularly the Ministry of Agriculture, Forestry and Fisheries, to offer training programs that focus on modern agricultural techniques aimed at enhancing both the quantity and quality of crop production. Additionally, the study highlights the absence of an institution dedicated to analyzing land types and quality in Cambodia. Moreover, the establishment of an effective irrigation system is crucial for the successful growth of crops.

High temperature perturbs physicochemical parameters and fatty acids composition of safflower (Carthamus tinctorius L.)

Future climates will realise increasingly frequent extreme weather events, which will impact on the quantum and quality of crop production. While effects of extreme heat on crop production have been well studied hitherto, there remains a dearth of knowledge pertaining to the impacts of extreme heat on grain quality. As such, our purpose here was to evaluate the effects of terminal heat stress on the physicochemical properties and composition of seed oil of safflower plants. Using two contemporary cultivars with varying genetic tolerance to heat stress (Faraman and Sofeh), we found that exposure to extreme heat reduced grain yield by 53–57%. Four fatty acids (palmitic, stearic, oleic and linoleic acid) comprised 96–99% of total fatty acid methyl esters; relative composition varied in response to heat stress and other environmental conditions. In the first experimental year (2017-18), saturated fatty acids in Sofeh and Faraman cultivars increased by 69% and 18% respectively, while unsaturated fatty acids decreased by 9% and 4%, respectively. In the second experimental year (2018-19), saturated fatty acids increased by 10% in Sofeh and by less than 1% in Farman, while unsaturated fatty acids in both cultivars were not significantly altered. Physicochemical parameters differed across years and cultivars; exposure to high temperature increased chlorophyll and carotenoid content in Sofeh, but decreased the said parameters in Faraman. In 2017-18, effects of heat stress on thiobarbituric acid were variable, but in 2018-19, thiobarbituric acid increased in both cultivars. In all cases, saponification and iodine content increased in response to heat stress. In sum, the fatty acid profile of safflower exposed to terminal heat stress was less affected compared with oil physicochemical parameters, due to greater temperature sensitivity of the latter.

Influence of mineral fertilizers and liming on the dynamics of CO<sub>2</sub> emissions, crop yield and quality of crop products of crop rotation link

In the field experiment was investigated the effect of repeated lime application on CO2 emissions from the soil, yield and quality of plant products against the background of mineral fertilizers N90P90K90, on dark gray forest heavy loamy soil. As a result of liming and improvement of the acid regime in the soil, prerequisites are created to enhance the vital activity of beneficial microorganisms in the experiment. It was revealed that an increase in biological activity (carbon dioxide emissions) against the background of the application of mineral fertilizers N90P90K90 and CaCO3 ensures high yield and product quality, contributes to favorable conditions for preserving soil fertility and to a greater extent stimulates the development of microorganisms using mineral forms of nitrate nitrogen. With the systematic use of mineral fertilizers N90P90K90 at the stage of crop rotation, an increase in the quality of cultivated crops was noted (the nutritional value of the green mass of clover; the content of crude protein, protein, gluten, starch in barley grain; the nature of grain in winter wheat). In different years of research, according to weather conditions, grain with a high content of crude gluten, protein, nature in winter wheat grain, starch in barley, ash nutrition elements in clover was obtained. The best option turned out to be using dolomite flour and (N90P90K90). All the considered quality indicators of winter wheat improved under the influence of fertilizers and lime, and the difference with the control was: protein – 0,64–1,78%; crude gluten – 1,6–4,3%; grain nature – 11–26 g/l. The highest productivity was obtained when applying mineral fertilizers and lime: barley – 3,53 t/ha, clover hay of the first year of use – 77,53 t/ha, winter wheat – 7,89 t/ha, compared with the control without the use of fertilizers.

Implications of soil waterlogging for crop quality: A meta-analysis

Soil waterlogging in many arable regions of the world challenge the quantum and quality of crop production. While previous studies have assessed the impact of waterlogging on crop yields, understanding of how waterlogging implicates with crop quality remains in its infancy. Here, we conduct a systematic literature review and meta-analysis to assess how waterlogging influences grain quality. We also explore the role of engineering and agronomic strategies for alleviating adverse effects of waterlogging. We reveal that soil waterlogging has less impacts on grain quality than on yield; the latter decreasing by an average of 23 %, while average grain protein and starch content of waterlogged crops reduced by 6.7 % and 7.3 %, respectively. We attribute these differences to underlying mechanics of yield and grain quality formation, as well as biological processes conferring adaptation, plasticity and recovery. Reduced grain quality under waterlogging is associated with decreased activity of enzymes involved in leaf nitrogen and carbon metabolism. Unlike yields however, grain quality suffers less deterioration with prolonged waterlogging, with ultimate effects realized being a function of species-specific tolerance, timing and duration of waterlogging relative to crop stage, soil type and growing season weather. We underscore the potential in engineering and/or agronomic interventions for alleviating detrimental effects of waterlogging.

Integrating GEE and IWQI for sustainable irrigation: A geospatial water quality assessment

The surface and sub-surface water quality is one of the decisive parameters for sustainable agriculture and water resources management. Deteriorating water quality impacts the irrigation, crop production, and human health. Therefore, the present work made an attempt to identify the water suitability for irrigation using the contemporary approach i.e. Irrigation Water Quality Index (IWQI) and Zone mapping using GIS techniques, and demonstrated for case of Wadhwan, Gujarat India. Three indices i.e., NDVI, NDWI, and LSWI were mapped using Landsat satellite imagery, whereas, Watermask index was mapped using Sentinel II satellite imagery for the assessment of the availability of water in different forms. The IWQI has applied to categorize the water quality as severe, high, moderate, low, and no restriction. The IWQI in the study area ranges from 6.4 to 62.5. The overall the water quality of study area shows that the 13.64 % of the region in severe restriction range, 56.82% in high restriction range, and 29.54% in moderate restriction range, which is in alarming for farmers and policy makers. The GIS zoning map effectively visualized the spatial distribution of IWQI, helping decision-makers to identify severity zones. Furthermore, the Piper diagram analysis has been performed, which shows that the water quality of the study area falls under mixed Ca2+-Mg2+-Cl-, mixed Ca2+-Na+-HCO3-, and Na-HCO3 types. The results revealed that major areas are in moderate to severe restriction zones, lying under deteriorated water quality, and need immediate attention for improvement before use. The IWQI advances SDG 2 (Zero Hunger) by optimizing water quality for crop production and SDG 6 (Clean Water and Sanitation) by ensuring sustainable water resource management, while indirectly supporting SDG 15 (Life on Land) through improved soil health and land management practices.

Enhancing tomato (Solanum lycopersicum) yield and nutrition quality through hydroponic cultivation with treated wastewater

Utilizing treated wastewater for crop cultivation is essential in regions with scarce freshwater resources for irrigation. This study evaluated the growth, fruit yield, nutritional and phytochemical quality of tomato fruits cultivated using a treated wastewater-based hydroponics system developed for the Trans Himalaya, India. Tomatoes grown with treated wastewater exhibited better growth, yield, nutritional content, phytochemical properties, and antioxidant activities than those grown in soil. Specifically, the lycopene and β carotene were significantly (p < 0.05) higher in tomato fruits cultivated in treated wastewater (0.05 ± 0.00 and 0.09 ± 0.00 mg/g) than soil (0.02 ± 0.00 and 0.01 ± 0.00 mg/g). Also, significantly (p < 0.05) higher carbohydrate and protein contents (55.91 ± 1.19 and 21.34 ± 0.31 mg/g, respectively) were obtained under-treated wastewater than soil (39.48 ± 0.07 and 18.52 ± 0.10 mg/g). Similar trends were also obtained in phytochemicals and mineral analysis. However, morphological, proximate, and phytochemical characteristics of tomatoes in nutrient and wastewater-based hydroponics were comparable. Treated wastewater offers eco-friendly benefits for quality crop production.

The influence of soybean rhizobia on the agricultural seeds sowing qualities

To grow high and stable yields with good product quality, it is very important to receive timely, full-fledged and friendly shoots of optimal density. Therefore, the problem of stimulating, or inhibiting, seed germination and the processes occurring in them occupies an important place in modern crop production. The method of pre-sowing seed treatment with rhizobia is one of the promising technological measures that ensure an increase in yield and quality of crop production. The staff of the Laboratory of Biological Research of the Federal State Budgetary Budgetary Institution of the Federal Research Institute of Soy conducted a study of the possibility of stimulating germination and disinfection of soybean seeds, lupin, vigna, wheat, barley using pure Sinorhizobium fredii crops. The work used collectible strains of rhizobia, which showed an abundant growth of bacterial mass on the nutrient medium of the MRC. The standard strain was S. fredii 5851 from the collection of microorganisms and cell cultures of the Leibniz Institute (DSMZ), Germany. In variants with strains, stable stimulating and healing effects were observed. As a result of a scientific experiment, it was found that, on average, in variants with S. fredii strains, germination increased by 37%, the length of seedlings – by 224%, the raw weight of seedlings – by 23% compared with the control (without treatment with strains). S. fredii strains BB-49, SB-39, SB-43, TB-422, TB-488, TB-490, TB-496, 062 maximally stimulated the process of germination of agricultural seeds.

Nutrient Management Through Organic Sources in Summer Green Gram

Background: Pulses are source of supplementary protein to daily diets based on cereals and starchy food for predominant vegetarian population. So, pluses are therefore often regarded as poor man’s meat. Greengram is third most important pulse crop growing after chickpea and pigeon pea in India. For maintain soil health, better quality crop production, organic fertilizer managements play important role. Methods: The experiment on nutrient management thought organic sources in summer green gram conducted with aim to know the effect of organic nutrient management on the growth, yield and quality of green gram at College Agronomy Farm, B.A. College of Agriculture, Anand Agricultural University, Anand during summer season of 2018 to 2020 in sandy loam soil of middle Gujarat. There were ten treatments of organic sources including no manures (control) treatment. They were replicated four times in randomized block design. Result: Three years experiment data revealed that application of vermicompost @0.5t/ha+Bio NP (Rhizobium and PSB) reported higher plant height at harvest, number of pods per plant, test weight, seed yield, harvest index and net return and BCR. Green gram haulm yield and soil microbial count was significantly higher in treatment T6 (FYM @ 2.0 t/ha+Bio NP (Rhizobium and PSB), treatment T8 (Castor cake @ 0.25 t/ha+Bio NP (Rhizobium and PSB), reported higher potassium content in haulm, Response of organic manures treatments found non-significant in case of initial plant population, plant height and number of branches per plant at 30 DAS, protein content, micronutrient content in seed, haulm and soil, except Mn in seed, heavy metal content in seed, haulm and soil, after harvest soil nutrient EC, organic carbon and available K2O, whereas same results also observed in case of nutrient content in seed and haulm.

Assessment of soil fertility and nutrient management strategies in calcareous soils of Khuzestan province: a case study using the Nutrient Index Value method.

Soil fertility (SF) is a crucial factor that directly impacts the performance and quality of crop production. To investigate the SF status in agricultural lands of winter wheat in Khuzestan province, 811 samples were collected from the soil surface (0-25cm). Eleven soil properties, i.e., electrical conductivity (EC), soil organic carbon (SOC), total nitrogen (TN), calcium carbonate equivalent (CCE), available phosphorus (Pav), exchangeable potassium (Kex), iron (Fe), copper (Cu), zinc (Zn), manganese (Mn), and soil pH, were measured in the samples. The Nutrient Index Value (NIV) was calculated based on wheat nutritional requirements. The results indicated that 100%, 93%, and 74% of the study areas for CCE, pH, and EC fell into the low, moderate, and moderate to high NIV classes, respectively. Also, 25% of the area is classified as low fertility (NIV < 1.67), 75% falls under medium fertility (1.67 < NIV value < 2.33), and none in high fertility (NIV value > 2.33). Assessment of the mean wheat yield (AWY) and its comparison with NIV showed that the highest yield was in the Ramhormoz region (5200kg.ha-1), while the lowest yield was in the Hendijan region (3000kg.ha-1) with the lowest EC rate in the study area. Elevated levels of salinity and CCE in soils had the most negative impact on irrigated WY, while Pav, TN, and Mn availability showed significant effects on crop production. Therefore, implementing SF management practices is essential for both quantitative and qualitative improvement in irrigated wheat production in Khuzestan province.

Pendampingan Demplot Teknik Budidaya Bawang Merah pada Musim Hujan Secara Ramah Lingkungan

Background: Shallot cultivation in the rainy season faces the constraints of more severe plant disease problems. Utilization of mixed biopestisda Trichoderma harzianum, Bacillus sp. B8 and Pseudomonas flourescens P8 as well as proper cultivation techniques have not been adopted by farmers. It is necessary to assist farmers in implementing the technology The objectives of the activity are: assisting farmers in implementing the shallot cultivation technology package appropriately, increasing the quantity and quality of crop production, and increasing farmers' income through increasing farm efficiency. Method: The farmers participating in the activity are members of the farmer group "Lestari" Tambak Sogra Village, Sumbang District, Banyumas Regency. Technology transfer method through demplot assistance. The biopesticide technology package and environmental manipulation are compared to the conventional package of synthetic chemical pesticides. Data on the growth and yield of technological plot crops compared to conventional plots. The large number of farmers who can independently apply the technology is observed. Results: mentoring activities showed that farmer group members were able to independently implement technology packages. The use of biopesticides and proper cultivation techniques can produce growth and yield equivalent to the use of synthetic chemical pesticides. Conclusion: 80% partner farmers can apply technology packages, the use of biopesticides is able to substitute the use of synthetic chemical pesticides, technology packages are able to increase 5.9% of shallot bulbs and reduce 75% production costs.

Effects of the Agrivoltaic System on Crop Production: The Case of Tomato (Solanum lycopersicum L.)

Climate change, with rising temperatures, water crises, and an increased frequency of climate disturbances, poses a threat to the ability of agroecosystems to ensure human access to food by affecting both the quantity and quality of crop production. Currently, there is growing knowledge about the fact that agrivoltaic systems may represent a direct strategy to cope with climate change driven by carbon dioxide emissions for energy production, preserving the capacity of agroecosystems to maintain food security. The aim of this work was to investigate the impact of environmental conditions generated by photovoltaic (PV) panels for sustaining open-field tomato (Solanum lycopersicum L.) fruit production under varying water supply regimes. Tomato plants were grown beneath PV panels or in full sunlight. In each scenario, two plots with an equal number of plants were subjected to different irrigation levels: high watering (HW) and low watering (LW). The results showed a lower number of tomato fruit produced grown under the PV panels, with an increased fruit size and water content under a normal water supply. The Brix degrees of the tomato fruits grown under the panel were more comparable to the fruits commercially available on the market than the Brix degree of the fruits grown in open-field sunlight. Thus, our data supported the conclusion that the agrivoltaic system, in the context of climate change with the enduring drought and long-term water scarcity, can be a good adaptation strategy to maintain favorable tomato production compared to the full sunlight conditions. Furthermore, these results can be important for planning breeding programs, since in many cases, the tomato fruits grown in full sunlight were seedless.

IoT-based greenhouse technologies for enhanced crop production: a comprehensive study of monitoring, control, and communication techniques

According to various studies, different countries have different climate conditions that affect the quantity and quality of crop production. Farmers want to use novel technologies that can help them produce crops in large quantities with good quality. The greenhouse is one of the rapidly growing technologies used for the production of crops. It protects the crops from changes in external weather conditions and, hence, helps to produce good-quality crops throughout the year. This work proposes a deep study of the technologies used in the greenhouse for the monitoring and control of various environmental parameters that affect the quality and production of the crops. This work also analyses the different communication techniques, relays, and sensors used for monitoring and controlling the different greenhouse parameters. Also, give details on sensors and the advantages and disadvantages of different communication technologies so that farmers can easily understand which technology is most suitable for their greenhouse. This study helps the farmers adopt the best-suited techniques in their green houses that are cost-friendly, easy to use, and have a longer life.

Effects of Different Rates of Sugarcane Biochar on Amelioration of Adverse Salinity Effects in Calcareous Clay Soil

ABSTRACT Soil salinity is a major challenge in agriculture, particularly in calcareous soils with high calcium carbonate levels. Biochar, produced from biomass pyrolysis, is being considered as a potential solution for mitigating salinity effects. A greenhouse pot experiment was conducted using calcareous soil from a saline field to investigate the effects of sugarcane biochar applied at different rates (0.0%, 2.0%, and 5.0%) on soil properties and wheat (Triticum aestivum L.) growth. Results showed that both Low Rate (2.0% biochar) and High Rate (5.0% biochar) treatments significantly improved soil pH, reduced electrical conductivity (EC), and increased soil organic matter (SOM) content. Plant growth indicators such as plant height, stem diameter, and leaf chlorophyll content also showed significant improvement with biochar application. High Rate had more pronounced effects compared to Low Rate. The analysis confirmed the significant effects of biochar on soil properties and plant growth, indicating its potential as a beneficial soil amendment. Sugarcane biochar has the potential to mitigate salinity stress and enhance crop productivity in calcareous soils. Further research is needed to explore the long-term effects of sugarcane biochar application and its interactions with other soil management practices in different crop systems. These findings highlight the promising role of biochar as a sustainable approach for mitigating salinity stress in agriculture and improving soil quality for crop production.

ИНТЕЛЛЕКТУАЛЬНАЯ АВТОМАТИЗИРОВАННАЯ СИСТЕМА УПРАВЛЕНИЯ СОРТИРОВКОЙ ФРУКТОВ

The development of effective technologies to reduce labor costs for the production, storage and processing of agricultural products is a difficult task. One of the promising directions of increasing the efficiency of technological processes in the agro-industrial complex is the full use of vision systems and artificial intelligence algorithms. Assessment of the quality of crop production is applied at various stages of production and allows detecting its damage, including during sorting. Due to the high productivity of production lines at the facilities of the agro-industrial complex, it seems effective to use intelligent information and control systems operating on the basis of machine learning algorithms. (Research purpose) The research purpose is proposing an approach to the creation of an intelligent automated control system for the fruit picking process using a vision system. (Materials and methods) Considered the structure of the information and control system of fruit sorting using a system of technical vision and machine learning. We implemented the test architecture of the neural network using the Keras library based on the Python language, the research was carried out in the google.collaborate service. A prepared data set based on images obtained on the production line was used to train the neural network. (Results and discussion) The structure of the convolutional neural network architecture was obtained, which allows us to adequately and with a sufficient accuracy solve the problem of classifying fruits into healthy and damaged ones in order to integrate it into an intelligent information and control sorting system. (Conclusions) Proposed an approach to improving the fruit sorting process, for example, for further processing into juice, using a technical vision system and machine learning. The structure of a convolutional neural network was developed to solve the problem of classifying apples by appearance, which became the basis for creating an intelligent information and control system for assessing the area of damage to the surface of fruits.

The Current Situation and Countermeasures of Agricultural Mechanization Development in Kailu County

With the continuous improvement of the level of science and technology, agricultural mechanization can rapidly develop and provide strong support for agricultural mechanization. The rapid popularization of agricultural mechanization of grass-roots agricultural development, maximizing the reduction of the degree of labor of farmers, for the high quality of crop production provides the conditions, but also greatly improve the efficiency of agricultural production. This paper analyzes and discusses the main functions of Kailu County Agricultural Machinery Bureau, and learns about the fulfillment of the functions of Kailu County Agricultural Machinery Bureau by means of a questionnaire. It analyzes the existing problems of the main functions of the Kailu County Agricultural Machinery Bureau and discusses the reasons for the problems. Analyze the actual situation of the main functions of the Kailu County Agricultural Machinery Administration, and put forward reasonable countermeasures and suggestions in line with the development of the main functions of the Kailu County Agricultural Machinery Administration.

USE OF NEW GENERATION FERTILIZERS ON WINTER TRITICALE CROPS

The article scientifically substantiates the literary sources on the cultivation of winter triticale for grain and green fodder. It is proved that the use of new high-yielding varieties of winter triticale is a powerful factor in stabilizing the grain economy of the country. Therefore, in this context, it is important to use the latest measures in innovative technologies to increase the yield and quality of crop production. Among the innovative measures in the technological process of growing agricultural crops, foliar feeding of plants with microfertilizers of biological, organic and chemical origin has become widely popular. With the correct application of these preparations, foliar feeding can be a more effective tool for eliminating the deficit in micro- and macroelements, compared to the application of mineral fertilizers in the soil, since nutrients directly enter the plant tissue in critical stages of development. Foliar fertilization does not replace soil application of fertilizers, but contributes to the effective addition of the main nutrition system and ensures an increase in the yield and quality of agricultural crops. It has been established that winter triticale is a promising, high- yielding crop, regardless of its direction of use (grain, green mass). By biological characteristics, the growth rates of the stem of winter triticale are determined by the genetic trait characteristic of all cereal crops. It has been established that from the tillering stage to the full exit into the tube, that is, during this interphase period, the height of the plants increased by 2.2-2.3 times, regardless of the varietal characteristics of the culture. It has been previously found that the use of Dr Green preparations for foliar feeding during the main growth and development phases is aimed at suppressing growth processes in height, starting from the full exit into the tube.

Influence of Silicon-Containing Agro-Ore (Diatomite) on the Yield of Agricultural Crops and the Quality of Crop Production

In the soil and climatic conditions of the forest-steppe of the Middle Volga region, the effect and aftereffect of various doses of silicon-containing agro-ore (diatomite) and its combinations with bird droppings on the productivity of agricultural crops has been scientifically substantiated and experimentally proven. The highest effect on the productivity of corn, spring wheat, annual grasses was provided by the complex action and aftereffect of silicon-containing agricultural ore together with bird droppings. The yield of corn grain in these variants varied from 5.48 to 5.92, spring wheat – from 3.12 to 3.33, hay of annual grasses – from 9.15 to 10.2 t/ha. The total productivity of crops of the grain-to-crop rotation link when using silicon-containing agricultural ore (diatomite) mixed with bird droppings varied in the range from 13.0 to 14.1 tons of grain/ha, exceeding the control by 3.36–4.44 tons of grain/ha, or by 34.8–45.9%.

Multi-Sensor Remote Sensing to Estimate Biophysical Variables of Green-Onion Crop (Allium cepa L.) under Different Sources of Magnesium in Ismailia, Egypt

Foliar feeding has been confirmed to be the fastest way of dealing with nutrient deficiencies and increasing the yield and quality of crop products. The synthesis of chlorophyll and photosynthesis are directly related to magnesium (Mg), which operates in the improvement of plant tissues and enhances the appearance of plants. This study aimed to analyze the correlation between two biophysical variables, including the leaf area index (LAI), the fraction of absorbed photosynthetically active radiation (FAPAR), and seven spectral vegetation indices. The spectral indices under investigation were Atmospherically Resistant Vegetation Index (ARVI), Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Disease–Water Stress Index (DSWI), Modified Chlorophyll Absorption Ratio Index (MCARI), the Red-Edge Inflection Point Index (REIP), and Pigment-Specific Simple Ratio (PSSRa). These indices were derived from Sentinel-2 data to investigate the impact of applying foliar applications of Mg from various sources in the production of green-onion crops. The biophysical variables were derived using field measurements and Sentinel-2 data under the effects of different sources of Mg foliar sprays. The correlation coefficient between field-measured LAI and remotely sensed, calculated LAI was 0.72 in two seasons. Concerning FAPAR, it was found that the correlation between remotely sensed calculated FAPAR and field-measured FAPAR was 0.66 in the first season and 0.89 in the second season. The magnesium oxide nanoparticle (nMgO) treatments resulted in significantly higher yields than the different treatments of foliar applications. The LAI and FAPAR variables showed a positive correlation with yield in the first season (October) and in the second season (March). Yield in treatment by nMgO varied significantly from that in the other treatments, ranging from 69-ton ha−1 in the first season to 74.9-ton ha−1 in the second season. Linear regression between LAI and PSSRa showed the highest correlation coefficient (0.90) compared with other vegetation indices in the first season. In the same season, the highest correlation coefficient (0.94) was found between FAPAR and PSSRa. In the second season, the highest accuracy to the estimate LAI was found in the correlation between MCARI and PSSRa, with correlation coefficients of 0.9 and 0.91, respectively. In the second season, the highest accuracy to the estimate FAPAR was found with the correlation between PSSRa, ARVI, and NDVI, with correlation coefficients 0.97 and 0.96, respectively. The highest correlation coefficients between vegetation indices and yield were found with ARVI and NDVI in the first season, and only with NDVI in the second season.

Riverine nitrogen footprint of agriculture in the Mississippi–Atchafalaya River Basin: do we trade water quality for crop production?

Increasing food and biofuel demands have led to the cascading effects from cropland expansions, raised fertilizer use, to increased riverine nitrogen (N) loads. However, little is known about the current trade-off between riverine N pollution and crop production due to the lack of predictive understanding of ecological processes across the land-aquatic continuum. Here, we propose a riverine N footprint (RNF) concept to quantify how N loads change along with per unit crop production gain. Using data synthesis and a well-calibrated hydro-ecological model, we find that the RNF within the Mississippi–Atchafalaya River Basin peaked at 1.95 g N kg−1 grain during the 1990s, and then shifted from an increasing to a decreasing trend, reaching 0.65 g N kg−1 grain in the 2010s. This implies decoupled responses of crop production and N loads to key agricultural activities approximately after 2000, but this pattern varies considerably among sub-basins. Our study highlights the importance of developing a food–energy–water nexus indicator to examine the region-specific trade-offs between crop production and land-to-aquatic N loads for achieving nutrient mitigation goals while sustaining economic gains.