Application Rates Research Articles

Assessing the Spatial Distribution, Condition, and Intensity of Soil Acidity for Informed Management Decisions in the Semen Aari District of Ari Zone, Southwestern Ethiopia

Soil acidity poses a significant challenge to agricultural productivity in Ethiopia's highlands, particularly affecting the Semen Ari district in the Ari zone. The common practice of applying agricultural lime to mitigate soil acidity is hampered by a lack of detailed information on the extent, severity, and spatial distribution of acidic soils. This study aims to determine how soil acidity varies spatially by identifying and mapping the specific geographic patterns of soil acidity levels in the Semen Ari district. Seventy-one composite soil samples from the 0–20 cm layer were geo-referenced and analyzed. Using statistical analysis and ArcGIS software for spatial interpolation through ordinary kriging, soil pH ranged from 3.29 to 5.68, classifying 99% of the soils as strongly acidic. The root mean squared error (RMSE) of the interpolation was 0.30. Soil pH showed a significant negative correlation with exchangeable acidity but a non-significant negative correlation with organic carbon and total nitrogen. The results highlight the need for targeted soil management strategies, such as appropriate lime application rates and the cultivation of acid-tolerant crops, to enhance crop yields. Further research is recommended to include comprehensive soil property datasets to better understand the factors influencing soil pH variability, thus supporting more precise management of acidic soils in the region. The generated high-resolution soil acidity map serves as a valuable tool for agricultural planning and decision-making.

Assessment of direct nitrous oxide emissions and emission factors from sugarcane plantations using different rates of chemical fertilizer application in western Thailand

Assessment of direct nitrous oxide emissions and emission factors from sugarcane plantations using different rates of chemical fertilizer application in western Thailand

SPECTROSCOPIC INVESTIGATIONS ON SELF-CLEANING FILMS FOR PHOTOVOLTAIC GLASSES

Titanium dioxide thin coatings are widely used in different fields for the manufacture of various products:electrochromic displays, photocatalytic systems, photosensitized solar cells and many others. At the same time, the possibilities for obtaining protective coatings based on TiO2 are of interest. The chemical and physical characteristics of the TiO2 coatings depend on a large extent of the applied technological method and the temperature values of the heat treatment used. Coatings are prepared by sol gel method applying dip coating technique. The present study characterizes self-cleaning TiO2 thin films for the photovoltaic application. The studies were carried out at different ratios of the components involved, rate of application of the solution on the glass substrate and different curing and holding temperatures. The coatings are dense and nanocrystal line according to AFM studies and optically transparent according to UV-Vis-NIR spectra.

Zoysia spp. putting green tolerance to postemergence herbicides

AbstractSpecies of Zoysia Willd. are used on approximately 9550 ha of golf course surfaces throughout the United States, primarily fairways and tees in transitional climates. Recently, cultivars featuring dwarf canopy height and improved quality have been released for putting green use; however, tolerance of these cultivars to postemergence herbicides is unknown. Field research was conducted in 2021 and 2022 evaluating the tolerance of Prizm® [Zoysia matrella (L.) Merr.] and Lazer® [Z. matrella (L.) Merr. × Zoysia minima (Colenso) Zotov] zoysiagrass to pyrimisulfan + penoxsulam (Aethon™), pyrimisulfan (Arkon™), flazasulfuron (Katana®), 2,4‐D + quinclorac + dicamba + sulfentrazone (Q4® Plus), 2,4‐D + MCPP + dicamba + carfentrazone (SpeedZone® EW), 2,4‐D + MCPP + dicamba + sulfentrazone (Surge®), and pyrimisulfan (formulated as a granule; Vexis®). A nontreated check was included for comparison. All of these herbicides have commercial labeling for use on zoysiagrass (Zoysia Willd.); however, none of these herbicides have labeling for use on zoysiagrass putting greens. Application rates in this study exceeded label maximums (for use on zoysiagrass) to ascertain the upper limits of Prizm® and Lazer® tolerance to these herbicides in Knoxville, TN and College Station, TX, respectively. Plots were arranged in randomized complete block design with four replications at both sites. Turfgrass injury was visually evaluated with data subjected to analysis of variance. Prizm® in Tennessee exhibited commercially acceptable tolerance to the applied herbicides, resulting in ≤8% injury either year. Lazer® in Texas sustained injury ranging from 21% to 61% and 10% to 31% in 2021 and 2022, respectively. Conditions of extreme heat and drought in Texas may have exacerbated differences in Lazer® tolerance to applied herbicides between years. Additional research across varying geographies and environmental conditions is needed to better understand tolerance of new zoysiagrass putting green lines, particularly within Z. minima.

Contact Toxicity and Repellent Activity of a Powder Extracted from Tridax Daisy (Tridax procumbens) against Maize Weevil (Coleoptera: Curculionidae)1

Abstract The maize weevil (Sitophilus zeamais Motschulsky) is a significant pest affecting stored seeds and grains, leading to substantial losses in both quantity and quality. Utilizing crushed plant powders derived from specific natural plants offers a promising alternative to synthetic insecticides, which pose risks to both consumers and the environment. This study aimed to evaluate the contact toxicity of Tridax daisy (Tridax procumbens L.) plant powder derived from its aerial parts against S. zeamais when incorporated into jasmine brown rice, Oryza sativa L., grains. Laboratory experiments were conducted at 30°C ± 5°C and 70% ± 5% relative humidity following a completely randomized design with four replications and five treatments. Jasmine brown rice grains were treated with different application rates of 0 (control), 20, 40, 60, and 80 g/kg, with five pairs/replicate of 7-d-old S. zeamais. Results showed that T. procumbens powder exhibited a contact toxicity of 93.08 g/kg of grain after 12 d, resulting in a mortality of 27.5%. Additionally, the F1 generation comprised 51 adults, indicating an 85% reduction in adult progeny emergence. These findings demonstrate the potential of T. procumbens powder as a natural grain protectant to control S. zeamais populations in storage.

Performance Assessment of the Small and Medium-Scale Coconut Weeder Cum Fertilizer Applicator Developed by Rajarata University of Sri Lanka

The enhancement of coconut yield significantly hinges on proper weeding and chemical fertilizer application. In Sri Lanka, several mechanical methods have been introduced for weeding and fertilizer application of coconut, but the traditional manual approach persists most popular, despite being time, labor cost intensive. Moreover, the introduced technologies were suited for large-scale coconut cultivation and could not cope with medium or small-scale. Furthermore, most of them are designed for a single application; weeding or fertilizing. Thus, the Faculty of Agriculture, Rajarata University of Sri Lanka (RUSL), developed a coconut weeder cum fertilizer applicator for medium and small-scale coconut cultivations. However, it has not been properly evaluated and recommended for farmers. Consequently, this study sought to evaluate the performance of the above machine by conducting a comparative performance evaluation with the conventional method. A healthy, well-maintained, proper-spacing coconut plantation was selected from the faculty research unit, and each weeding and fertilizer application method was replicated ten times. In terms of performance parameters: effective field capacity, field efficiency, and weeding efficiency in mechanical and manual methods were 0.172 ha h-1, 61.86%, 66.62%, and 0.048 ha h-1, 55.34%, 60.35%, respectively. Statistical analysis indicates the mechanical method had higher field capacity and efficiency than the manual method, while weeding efficiency was not significantly different (p≤0.05). In addition, the machine had a fertilizer spreading uniformity of around 99.98% when operating at an optimum speed of 1.45 km h-1. Fertilizer application rate and performance index as a weeder were 1.7 kg/min and 1145.86, respectively. Furthermore, the fuel consumption rate of the machine was 0.733 L h-1 and its break-even point was recorded as 2.85 ha yr-1. Consequently, the coconut weeder cum fertilizer applicator proves suitable for medium and small-scale coconut cultivations in Sri Lanka.

Correction: Sharma et al. Rhizophagus irregularis and Nitrogen-Fixing Azotobacter with a Reduced Rate of Chemical Fertilizer Application Enhances Pepper Growth along with Fruit Biochemical and Mineral Composition. Sustainability 2022, 14, 5653

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Biochar application improves maize yield on the Loess Plateau of China by changing soil pore structure and enhancing root growth

Biochar application emerges as a valuable soil management strategy for enhancing crop yield; however, the mechanisms underlying the relationships between soil and plants remain unclear after biochar application. In this study, soil pore characteristics and maize yield were assessed in a five-year biochar-application experiment on the Loess Plateau of China, including four treatments: Control (no biochar), low-dose biochar application (LB, 3 t ha−1), moderate-dose biochar application (MB, 6 t ha−1), and high-dose biochar application (HB, 9 t ha−1). Root growth traits were evaluated by cultivating maize in intact soil cores collected from field conditions using X-ray computed tomography. Our findings indicate that, compared to the Control, the HB treatment enhanced macroporosity (> 0.1 mm in diameter), porosity of 0.1–0.5 mm pores, and saturated water content, while reducing macropore connectivity and penetration resistance. However, biochar application treatments did not alter the water retention characteristics from field capacity to permanent wilting point or the plant-available water content (PAWC). Furthermore, the mean angle of primary and seminal roots as well as the length and surface area of entire roots increased in the HB treatment, showing a positive correlation with the porosity of 0.1–0.5 mm pores. The mean diameter of primary and seminal roots, leaf fresh and dry weights, and maize yield also increased in the HB treatment compared to the Control. Partial least squares path modeling analysis indicated that biochar application rates positively impacted on root growth and plant productivity through an indirect influence of soil pore size distribution, with 0.1–0.5 mm pores being particularly crucial for facilitating deeper root penetration and root elongation. These findings demonstrate that biochar application primarily augmented 0.1–0.5 mm pores, rather than affecting smaller pores capable of retaining plant-available water or larger macropores, enhancing deeper rooting and root elongation, thus improving plant productivity and crop yield.

Implementation and evaluation of a mobile application to support occupational therapy education

Purpose This study aims to evaluate the usability and effectiveness of a mobile application, ValTO, designed to enhance communication and professional reasoning skills in occupational therapy students through a case-based learning approach. Design/methodology/approach A descriptive exploratory study was conducted with 32 second-year occupational therapy students. The usability of the app was assessed using the Mobile Application Rating Scale and the System Usability Scale, complemented by the University of Oviedo’s Learning Satisfaction Survey. Findings The majority of students (77.8%) rated the app above average on the System Usability Scale, with 50% scoring it as excellent. Mobile Application Rating Scale scores revealed high ratings across functionality, aesthetics and information quality, with a significant correlation between app usability and user satisfaction. Increased student satisfaction was also observed in the Learning Satisfaction Survey compared to previous years. Originality/value ValTO integrates modern mobile health tools into occupational therapy education, enhancing students’ decision-making skills in an innovative, real-world context. This study contributes to the growing body of research on mobile health applications in educational settings, demonstrating their potential to improve both student engagement and learning outcomes.

Taking Application Rates With a Grain of Salt: Uncovering the Impact of Road De‐Icing Salt on Freshwaters of a Mountain Catchment in the Italian Alps

ABSTRACTWhile application of salt for de‐icing purposes has been extensively studied in urban areas of North America, little attention has been paid to it in Europe, particularly in mountain areas. Here, after assessment of baseline salinity, and through applying different approaches (i.e., univariate statistical techniques, Multivariate Regression Trees, multivariate regressions), we investigated the potential changes in water chemistry and benthic macroinvertebrate community structure caused by the application of de‐icing salt over an entire winter season, in a mountain catchment located in the Italian Alps (N 46°, E 11°). Concurrently, we tested and compared the application of three different benthic macroinvertebrate indices used to assess salinisation impacts. Overall, we identified a constant level of baseline salinity across a 13‐year period, accompanied by a strong seasonality factor. Despite an application rate comparable to those of large North American cities, macroinvertebrate communities showed little evidence of change. However, chemical ions whose concentrations are known to be influenced by de‐icing salt (e.g., Na+, Cl−) were identified as the structuring drivers of the macroinvertebrate communities, thus suggesting that the studied riverine environment show a high potential for change in relation to salinity. In conclusion, we caution against the simple evaluation of application rates to assess the risk/level of salinisation within a catchment, and encourage further specific analysis and study of salinisation in mountain areas: they appear as sensitive habitats to potential variations in salinity, and stressors such as increased urbanisation and climate change will further exacerbate the risk of increasing salinisation in mountain freshwaters.

Distribution of phosphorus forms in soil amended with poultry litter of different ages and application rates: Agronomic and environmental perspectives

AbstractPoultry litter (PL) can be used as a viable alternative to phosphate fertilizers. However, there is a lack of information about phosphorus (P) distribution in inorganic (Pi) and organic (Po) forms and its transformation in soils amended with PL of varying age (based on litter clean‐out frequency) and application rate. This study aimed to determine the effect of PL age and application rate on soil P forms and their bioavailability. Soils were amended with 5 and 10 Mg ha−1 PL using 6‐, 18‐, and 30‐month‐old litter and incubated for 6 months. Soil P fractionation was performed following the Hedley protocol. Soil P availability and soil P storage capacity (SPSC) were determined using Mehlich 3 (M3) extraction. Results indicated that P transformation from labile to stable P forms occurred over 150‐day incubation. Litter age had no significant effect on the distribution of soil P forms. However, the highly reactive Pi (HRPi) form was higher for treatments with 10 Mg ha−1 PL on Day 0, indicating a risk for P loss, which was also revealed by negative SPSC for those treatments. At Day 0, M3‐P was positively correlated to HRPi. However, from Day 30 to 150, M3‐P was strongly correlated to both HRPi and moderately reactive Pi (MRPi) forms, indicating MRPi contribution to soil P availability. The negative relationship between HRPi and SPSC further confirms that high HRPi on Day 0 may be an environmental concern.

Highly Efficient Water and Nitrogen Application Strategies for Maintaining Summer Maize Yield in the North China Plain During Future Drought Years

ABSTRACTFuture frequent droughts threaten summer maize production in the North China Plain (NCP). A proper combination of irrigation and nitrogen (N) application can improve water and N use efficiency while maintaining summer maize yield. However, the optimal irrigation and N application strategies (OINASs) for summer maize during future drought years in the NCP require further exploration. This study applied the DSSAT‐CERES‐Maize model to investigate OINASs for summer maize for all drought years during 2021–2050 under three shared socioeconomic pathways (SSP1‐2.6, SSP2‐4.5, and SSP5‐8.5). The performance of the OINASs was subsequently evaluated against no irrigation and N application (CK) condition and a conventional irrigation and N application strategy (CINAS). The results highlight the following: (1) For all drought years under the three SSP scenarios, the base fertilizer rate should be 60 kg/hm2, after that the irrigation and N application are required during the jointing and heading periods. Under the SSP1‐2.6 scenario, the average values of irrigation and N application during each earlier period are 35.5 mm and 22 kg/hm2. Under the SSP2‐4.5 and SSP5‐8.5 scenarios, the average values are (34.5 mm, 23 kg/hm2) and (47.5 mm, 18 kg/hm2). (2) Under all SSP scenarios, the optimal irrigation amounts and N application rates are much lower than those under the CINAS. After applying OINASs for summer maize, an average of 1.16–1.22 billion kg of N and 2.98–5.19 billion m3 of freshwater will be saved per future drought year in the NCP. (3) Under all SSP scenarios, the summer maize yields under the OINASs are slightly and significantly greater than those under the CINAS and CK conditions. Moreover, both water and N use efficiencies improved under the OINASs compared with those under the CINAS, with more significant improvements in N use efficiency. The OINASs provide a practical way to ensure food security and environmental sustainability.

Developing Strategies to Mitigate Squash Injury from the Soil Residual Activity of Glyphosate in Bareground Systems

Fresh market vegetables are an essential component of the human diet. Maximizing yield is critical, and to achieve this goal, fields must be weed-free when vegetable crops are planted. Historically, removing emerged weeds just before planting has been accomplished using the herbicide glyphosate. However, recent research has indicated that glyphosate applied to sandy, low-organic-matter soils just before transplanting vegetables can be injurious. Two field experiments investigated 1) the response of transplanted squash to the residual activity of glyphosate, and 2) the effects of implementing tillage, irrigation, or extending the plant-back interval after application and before planting to mitigate injury from glyphosate. Glyphosate applied at 1.3, 2.5, or 3.8 kg ae/ha 1 day before transplanting injured squash 13%, 29%, and 53%, respectively; extending the interval between application and planting to 7 days reduced injury to 1%, 11%, and 28% at the same rates. An interaction between application rate and planting interval was also observed on squash plant widths and biomass, as well as early-season and total marketable fruit numbers and weights. Total marketable fruit number was reduced 29% and 52% by glyphosate at 2.5 or 3.8 kg ae/ha, respectively, and a reduction in fruit production of 36%, 28%, and 23% was observed when glyphosate was applied 1, 4, or 7 days before transplanting, respectively. In a separate study, light tillage (5 cm deep) was the most effective cultural practice evaluated because it eliminated damage by glyphosate. Overhead irrigation of 0.6 cm was not beneficial in mitigating injury by glyphosate. Recommendations from this research will help vegetable growers avoid injury from the residual activity of glyphosate through a FIFRA 2(ee) recommendation label.

Simulated herbicide drift alters native plant flowering phenology.

Data for herbicide effects on plant flowering are needed to determine potential impacts on plant reproduction. Thus, flowering phenology was determined for up to 12 weeks after herbicide treatment for native Willamette Valley plants growing in small plots on two Oregon State University experimental farms. Six perennial species were evaluated: Camassia leichtlinii (CALE), Elymus glaucus (ELGL), Eriophyllum lanatum (ERLA), Festuca idahoensis subsp. roemeri (FEID), Iris tenax (IRTE), and Prunella vulgaris var. lanceolata (PRVU). Effects of glyphosate and dicamba, alone and in combination, were determined using simulated drift rates of 0.1 or 0.2 x field application rates (FAR) of 1119 g ha-1 active ingredient (a.i.) (830 g ha-1 acid glyphosate) for glyphosate and 560 g ha-1 a.i. for dicamba. Flowering phenology was evaluated as stage of development on a scale from no buds (converted to 0), buds (1), pre-flowering (2), flowering (3), post-flowering (4), to mature seeds (5) before herbicide treatment and for 12 weeks after treatment. Flowering response to herbicides varied by species and farm; but, in general, dicamba and glyphosate resulted in earlier flowering stages (delayed or not full flowering) for the dicot ERLA, and to a lesser extent, PRVU; and glyphosate resulted in earlier flowering stages for the monocot IRTE. Based on these data, the concentration of herbicide affecting flowering stage was 0.1 x FAR. Once flowering stage was inhibited by dicamba and glyphosate, plants generally did not recover to full flowering. This study provided evidence that common herbicides can affect flowering phenology of native plants with implications for seed production.

Quantifying residents' exposure to agricultural pesticides using new geospatial approaches

A better understanding of environmental exposure to agricultural pesticides is crucial for public health, regulatory and management purposes. Residents in close vicinity to agricultural fields are likely to be more exposed to pesticides. In that context, an innovative geospatial approach for mapping estimates of agricultural pesticide exposure was developed in this study.Data on pesticide application rates, high-resolution annual datasets of the geographic distribution of crops, and the 100x100m grid population dataset were utilized to complete this analysis in Wallonia (Belgium) over the period 2015-2019. Pesticide exposure metrics were estimated using a buffer-based exposure model by conducting neighborhood analysis within a 1000m buffer radius. Subsequently, a population weighted method was used to ‘up-scale’ the exposure data to administrative levels. In a limited validation effort, model estimates were compared with pesticide measurements in air collected at 12 stations during the period 2015-2016.The results present the first modeling map of environmental exposure to agricultural pesticides for the whole of the Walloon region. The northern part of the Sambre-Meuse axis demonstrates more intensive agriculture and the highest pesticide weighted exposure indices. The majority of the population resides near agricultural areas, with only 4% living in regions that lack crops within a 1000m radius, primarily in the central areas of large cities. A positive trend association between pesticide measures in air and the index was observed at the different stations, nevertheless further validation efforts are needed to accurately compare the same active ingredients.This work gives a valuable basis for research and environmental health actions in Belgium. Maps highlight areas where human biomonitoring and epidemiological studies should be implemented to investigate the impact of potential environmental exposure to pesticides. This information helps policy-makers to take measures to control and reduce the load of agricultural pesticides in the environment.

An integrated tool for cost-effectively applying nutrient management practices for corn, soybeans, and wheat.

Harmful algal blooms (HABs) problem in Lake Erie has become critical recently-primarily triggered by phosphorus losses from cropland in the Maumee River watershed (major crops of corn/soybeans/wheat). Implementing agricultural best management practices (BMPs) is crucial to reduce excess nutrient loadings. Nutrient management is the management of nutrient applications for crop production that maximizes nutrient use efficiencies and minimizes nutrient losses. However, an integrated watershed-scale tool is needed for cost-effectively applying nutrient management practices for corn/soybeans/wheat considering the 4Rs (Right nutrient source, Right rate, Right time, and Right place of nutrient applications). In this study, by combining an improved Soil and Water Assessment Tool (SWAT) for nutrient management (SWAT-NM) and an improved BMP Cost Evaluation Tool (BMP-COST) for economic evaluations of nutrient management (BMP-COST-NM) considering the 4Rs for corn/soybeans/wheat, an integrated tool SWAT-COST-NM was created. SWAT-COST-NM was demonstrated in the AXL watershed (a typical agricultural area in the Maumee River watershed). The impacts of single nutrient management practices (single-NM, which separately changed the rate, place, time, or nutrient source of fertilizer applications) and combined-NM practices (multiple single-NM practices combined as one nutrient management practice) for corn/soybeans/wheat were evaluated. Tradeoffs in yearly net costs, crop yields, and March-July/yearly nutrient losses (Total Phosphorus-TP, Dissolved Reactive Phosphorus-DRP, and Total Nitrogen-TN) existed. Nutrient management did not necessarily lead to sufficient increases in crop yields to generate extra revenues that match or exceed the additional costs of the activities (compared to existing practices). One of the combined-NM practices could simultaneously reduce March-July TP, DRP, and TN losses by 5.89%, 8.19%, and 8.23%, respectively, while increasing crop yields with additional income (0.50 $/ha/yr of cropped area). SWAT-COST-NM, which can quantify various factors and tradeoffs when evaluating the impacts of nutrient management practices for corn/soybeans/wheat, can assist decision-makers in cost-effectively applying nutrient management practices considering the 4Rs.

Evaluating the Impact of Integrated Nutrient Management Practices on Land Productivity, Crop Residue Decomposition and Abundance of Soil Organisms in a Banana Plantation in Sri Lanka

The fertilization practices heavily influence the decomposition rate of organic materials added to soil. Hence, the nutrient management strategies that aim to improve crop yields may not necessarily support organic carbon accumulation in soil and overall soil fertility. This study investigated how land productivity, crop residue decomposition and diversity of soil organisms were affected by the combined use of chemical fertilizers (CF) and poultry manure (PM) in a banana plantation in Buttala, Sri Lanka. Banana yield, soil properties and decomposition of crop residues were studied in six treatments as, CF1+PM1, CF1+PM2, CF1+PM3, CF2 +PM1, CF2+PM2, and CF2+PM3. CF1 and CF2 correspond with 75% and 100% of recommended CF application rate. PM1, PM2 and PM3 correspond with PM application rates of 0, 2.5 and 5 kg/plant. Crop residue decomposition was assessed using litter bags containing two litter materials as banana pseudo-stem pieces and banana leaves and placed at two depths (surface and at 7.5 cm depth). Litter bags were recovered at 17, 31 and 45 days after placement (DAP) and weight loss of crop residues was determined. The application of poultry manure significantly increased (P<0.01) banana yield at first harvest and decreased (P<0.1) bulk density. Type of material and time of exposure to decomposition had significant effects (P<0.05) on litter decomposition but depth of placement and nutrient management strategy had no significant effect (P>0.05) on decomposition. By 45 DAP pseudo-stems were degraded more than leaves (67.47±13.99 % and 46.90±5.76 %, respectively). The abundance of culturable bacteria and cellulose decomposers in soil and the abundance of soil fauna in decomposing litter were significantly (P<0.1) increased with the PM application to soil. In conclusion, in the studied banana plantation, incorporation of PM in nutrient management increased land productivity and had positive impact on some soil properties, which are important determinants of soil fertility but did not register any effects on crop residue decomposition during the study period.

Accumulation of road salt in a calcareous fen: Kampoosa Bog, western Massachusetts.

Road salt poses a threat to the quality of soils and water resources. Wetlands located in salt contaminated areas are at risk of experiencing lower plant and animal species diversity. Therefore, it is critical to understand how modifications to salt application rates and hydrological events impact wetland water quality. Here, we use chloride mass flux, discharge, groundwater chloride concentration, meteorological, and salt application data from 2012-2020 to estimate chloride accumulation and outflux rates in the Kampoosa Bog subwatersheds, located in Stockbridge and Lee, Massachusetts, and bordered by major highways (Interstate-90 and U.S. Route 7). We also investigate the correlation between wetland size and chloride retention rate. During the 2018-2019 period, mean annual chloride application rates in the major watershed increased from 363000 kg/year (2012-2017) to 479000 kg/year. This led to a net chloride accumulation (KB100 subwatershed: 339000 kg; KB150 subwatershed: 188000 kg) and increased groundwater chloride concentrations in the fen. Chloride outflux from these subwatersheds was primarily driven by discharge. We found that the relationship between wetland percent cover and chloride retention is complex. Although the percent wetland cover is greater in the KB100 main wetland region compared to the KB150 subwatershed, high precipitation in 2018 resulted in similar chloride retention efficiencies (~26%). During the drier year (2019), chloride retention was higher in the wetland region due to its gentle slopes which promote water accumulation and consequently higher evaporation rates which lowers discharge and chloride outfluxes. The chloride steady-state concentration analysis also suggests that there is potential for chloride accumulation to continue because the watershed has not yet reached steady-state chloride concentrations. Without major modifications to salting practices, chloride concentrations will continue increasing and potentially promote the re-growth of invasives (Phragmites) and continued growth of salt tolerant species (Typha angustifolia/xglauca) that diminish plant diversity.

Socio-Demographic Characteristics and Adoption of Mobile Phone Applications for Improved Small-scale Commercial Agriculture in Makonde District, Zimbabwe

Mobile applications have provided a new way for agricultural transformation. This is set to revolutionise the agriculture sector with easy access to vital agricultural information on weather, market trends, pest, and disease management, and best agriculture practices to enhance agricultural productivity and profitability. However, there is a dearth of studies on the adoption of mobile applications in agriculture. It was important for this study to understand the impact of farmers’ demographic characteristics on the adoption of mobile applications in small-scale commercial agriculture. The study applied the quantitative research approach, a sample size of 213 small-scale commercial farmers, a descriptive cross-sectional research design, and the structured household questionnaire survey instrument, purposive random and stratified sampling techniques to collect primary data. Data was analyzed using descriptive statistics. The findings of the study revealed a higher adoption rate of mobile applications among young farmers than old farmers. The study indicated that female small-scale commercial farmers adopted mobile applications than male farmers. The study revealed that the majority of small-scale commercial farmers were literate. Further, the study highlighted that married farmers exhibited a greater tendency to adopt mobile applications than single, divorced, separated, and widowed. Furthermore, the study revealed that the majority of small-scale commercial farmers were engaged in agriculture as their primary occupation. The study argued that young farmers, female farmers, educated farmers, married farmers, and farming as a primary occupation positively influenced the adoption of mobile phone applications for improved small-scale commercial agriculture. The study recommends that policymakers and implementers should consider socio-demographic characteristics as critical determinants of the adoption of mobile phone applications for improved small-scale commercial agriculture to tailor strategies that promote the adoption of mobile applications based on different farmer age groups

Effects of Water–Nitrogen Interaction on Sandy Soil, Physiology, and Morphology of Tall Fescue (Festuca arundinacea Schreb) Turf

The soil water and nitrogen (N) levels are the important factors affecting turfgrass growth. However, the impact of the water–N interaction on tall fescue (Festuca arundinacea Schreb) in terms of the N metabolism and plant morphology remains uncertain. Therefore, the objective of this study was to investigate the impacts of different N and water levels on the physiological and morphological responses of tall fescue. The experiment was designed with N (N0, N2, and N4 representing N application rates of 0, 2, and 4 g m–2, respectively) and irrigation [W1, W2, W3, W4, and W5 representing field water capacities (FWCs) of 90~100%, 75~85%, 60~70%, 45~55%, and 30~40%, respectively] treatments, and the relevant indexes of the soil water content and soil NH4+–N and NO3−–N levels as well as the physiology and morphology of the tall fescue were determined. The results demonstrated significant changes in the contents of soil water (SWC) and N and the physiological and morphological indexes, except for the enzymes related to N metabolism, including nitrite reductase (NiR), glutamate dehydrogenase (GDH), and glutamate synthetase (GOGAT). The water stress significantly enhanced the water and N use efficiencies (WUE and NUE), except the NUE in the W5 treatment. The N stress significantly influenced the SWC, soil NO3−–N content, and physiological and morphological indexes, excluding malondialdehyde, NiR, GOGAT, and above- (AGB) and below-ground biomass, resulting in the increased WUE and NUE. The application of a low N rate effectively alleviated the detrimental impacts of water stress on the SWC and glutamine synthetase activity. In conclusion, W2 and N2 are deemed more appropriate treatments for the low-maintenance measures of tall fescue turf. Among all the treatments, N2W2 is recommended as the optimal water–N interaction treatment due to its ability to conserve resources while still ensuring high turf quality.