Variable Nutrient Research Articles

Morpho-Physiological Adjustment of Swietenia humilis Zucc. Plants to Varied Nutrient and Light Conditions and Their Performance in Nurseries and Fields Under Soils with Different Preparations

To enhance the plantation performance of Swietenia humilis Zucc., a threatened precious woody species from the dry tropics of Latin America, this study examined its morpho-physiological responses to variations in nutrient and light availability. We established a nursery trial with factorial treatments: three levels of fertilization (4, 6, and 8 g L−1 of substrate using a controlled-release fertilizer, CRF, 18-6-12) and two shade intensities (60% and 40%), alongside a full sun treatment. The field performance of nursery-raised plants was evaluated under two site conditions (with and without mechanical soil preparation) over 48 months. In the nursery, S. humilis exhibited diverse morpho-physiological characteristics influenced by the studied factors, with optimal growth observed at 6 g of the CRF and 40% shade. Mechanical soil preparation significantly improved plant survival, reducing mortality risk by 99.16% and increasing survival probability to nearly 75%. Height growth was also enhanced, being 2.5 times greater in the prepared site compared to that in the unprepared one. S. humilis showed acclimatization in the field, producing new foliage with high chlorophyll content. In conclusion, nursery management and soil site preparation influence the field performance of S. humilis. These findings have practical implications for improving the management of S. humilis in plantations across the dry tropics.

Evaluating citrus juice: A comparative study of physicochemical, nutraceutical, antioxidant, and antimicrobial properties of citrus juices from Nepal

Citrus fruit juice is highly beneficial to human health, providing essential nutrients like carbohydrates, vitamins, phytochemicals, and antioxidants. Juices from citrus fruit varieties grown in various regions of Nepal were analyzed for their physicochemical properties, nutraceutical content, antioxidant and antimicrobial properties. The pH of the juices ranged between 2.09 and 3.62, while total soluble solids (TSS) varied from 7° Brix to 12.3 °Brix. Among varieties, C. aurantifolia exhibited the highest titratable acidity at 7.39 g/100 mL. C. limon showed the highest moisture content (94.74 %), C. reticulata had the highest carbohydrate content (14.6 ± 0.4 g/100 mL, n = 3), and C. aurantifolia presented the highest protein content (34.1 ± 0.7 mg/100 mL). C. sinensis recorded the highest flavonoid content (91.4 ± 0.3 mg/100 mL), C. reticulata had the highest phenolic content (65.8 ± 0.6 mg/100 mL), and C. limon exhibited the highest ascorbic acid content (45.1 ± 0.4 mg/100 mL). The methanolic extracts of all citrus fruit juices demonstrated robust antioxidant properties, as determined by DPPH assay. Notably, C. limon and C. aurantifolia juice extracts demonstrated significant antimicrobial activity against a wide range of microbes. This study highlights the variation in nutrient and phytochemicals compositions among different citrus fruit juices, underscoring the nutritional and medicinal benefits of citrus species.

Effects of Straw and Green Manure Addition on Crop Yield, Soil Properties and CH4 Emissions: A Meta-Analysis

The incorporation of organic amendments is widely acknowledged for its capacity to enhance soil fertility and boost crop productivity. However, whether the addition of organic amendments can improve soil quality and crop production, simultaneously causing methane emissions in paddy fields, deserves further investigation. In this meta-analysis, the effects of different organic amendments on soil nutrient levels, rice yield and CH4 emissions were evaluated in paddy fields based on 328 observations from 77 field trial studies. Our results revealed that the addition of organic amendments significantly increased soil organic carbon (9.47%), microbial biomass carbon (21.13%), microbial biomass nitrogen (28.91%), urease (25.07%) and β-glucosidase (24.41%). Moreover, straw addition significantly increased the CH4 emissions by 152.68% and rice yield by 7.16%; green manure addition significantly increased CH4 emissions by 71.62% and rice yield by 10.09%, respectively. Although both increased the CH4 emissions, green manure had the ability to improve the availability of N, which could improve rice uptake. The regression results showed that the variation in crop yield, soil nutrients and CH4 emissions are influenced through the types and quality of organic amendments. Overall, this study suggests that organic amendments are beneficial in maintaining soil quality and improving rice yield, whereas it also increased the CH4 emissions. These meta-analysis results may provide some references for optimizing organic amendments incorporated into the soil to sustain soil fertility and crop production while mitigating soil constraints and methane emissions.

A Ten-year Nutrient Intake of an Elderly Cohort in South Africa

Food insecurity and malnutrition are often evident among the elderly population residing in low-income communities. This study is part of a broad collaborative investigation that recorded nutritional status, socio-demographic variables, and anthropometric indices from 2004 to 2014. The baseline was recorded for 2004, and a five-year follow-up was done for 2009, and 2014. The purpose of this study was to evaluate, over ten years, the dietary intake and nutritional status of elderly people in terms of anthropometric measurements at an elderly day care center, to determine if socio-demographic variables influence their diets, and if dietary intakes changed over the ten years. The study used a quantitative descriptive approach with a longitudinal cohort. This review only reflects the nutrient analysis of the diet amongst the cohort group (n=62). Measures included two 24-hour recalls assessing both the food and nutrient intake, as well as the dietary pattern of the cohort group. Results reflect many fluctuations in nutrient intake. Overall, participants consumed less energy, carbohydrates, and dietary fibre than dietary reference intakes (DRI), with protein intake above DRI during 2004 and 2009, but declining between 2009 and 2014. Micronutrient intake revealed calcium consistently below DRI, with variations in other nutrients over the years. Gender differences were significant for certain nutrients, with men generally consuming more niacin, vitamin B6 and vitamin E as compared to women. Median nutrient intakes failed to meet average requirements, except for protein, carbohydrates, chromium, riboflavin, pantothenate and vitamin K. Only a few nutrients, such as niacin, vitamin B6 and vitamin E reflected significant differences in values between the different genders. T-tests comparing nutrient averages between years found significant differences in fat intake between 2004 and 2009, and between 2009 and 2014, while protein differed significantly between 2009 and 2014. Other nutrients did not show significant differences across these periods, except for cholesterol and zinc between 2004 and 2014, and protein, fat, cholesterol, and zinc between 2009 and 2014. The collective picture reveals deficiencies, especially in key nutrients like zinc and iron, which fluctuated over a ten-year period. Analysis showed no significant difference in nutrient intake across the three periods, except for fat intake, which significantly differed between 2009 and 2014. Energy intake appeared to be higher from 2004 to 2009 but decreased notably by 2014. These findings underscore the importance of tailored dietary interventions to address nutrient deficiencies in aging populations, considering both individual needs and changing dietary patterns over time. Key words: Cohort, elderly, nutrient intake, food insecurity, dietary intake, care centre

Effects of cotton peanut rotation on crop yield soil nutrients and microbial diversity

Background and Aims Cotton-peanut rotation is a sustainable farming practice that enhances land utilization and promotes the sustainable development of agriculture. Crop rotation can reduce the occurrence of pests and diseases, as different crops have varying levels of resistance to such threats. Additionally, by alternating the types of crops grown, the soil environment is changed, which can lead to the elimination of favorable conditions for pathogens and pests, thereby alleviating the impact of these issues. Furthermore, cotton-peanut rotation can improve soil fertility.To investigate the effects of different crop rotation systems on crop yield, soil nutrients, and soil microbial communities. Methods: Using high-throughput sequencing technology, investigate the soil microbial diversity in the root zone after cotton-peanut rotation.Various planting patterns, including cotton continuous cropping (MC), peanut continuous cropping (HC), peanut-cotton-peanut rotation (HR), and fallow (X), were established to assess variations in crop yield, soil nutrients, and soil microbial diversity. Results: Significant differences were observed in crop yield, soil nutrients, and soil microbial community structure among different planting patterns. The HR system significantly increased the output compared with the HC and MC systems. Additionally, HR exhibited significantly lower total nitrogen (N) and basic nitrogen (BN) contents than HC and MC, whereas MC showed lower total potassium (K) and available potassium (AK) contents. HR led to a decrease in soil bacterial diversity but an increase in fungal diversity, with Ascomycota and Mortierellomycota being dominant. Various bacteria (Chloroflexi, Bacteroidota, and Actinobacteriota) associated with organic matter degradation and nutrient cycling were found across different planting systems, enhancing material cycling efficiency. Furthermore, Planctomycetota bacteria related to crop nutrient synthesis and Glomeromycota bacteria aiding plant nutrient absorption were significantly higher in the MC system than in the HR or HC systems. Redundancy analysis indicated a significant negative correlation between crop rotation and soil fungal community, whereas Ascomycota exhibited a significant negative correlation with organic matter.Conclusion: Peanut-cotton rotation can mitigate soil nutrient loss, enhance beneficial microorganism diversity, suppress harmful bacterial populations, stabilize ecosystems, and boost crop yield.

Host influence on life history traits of Ceratitis capitata Wiedemann in an arid region of Argentina.

The fruit fly Ceratitis capitata is a successful generalist due to the trade-off between different variables in its life history traits. The present study aimed to assess some life history traits of C. capitata recovered from peach, plum and fig, three key host species, under the climatic conditions of an irrigation oasis in the arid province of San Juan, Argentina. Pupal abundance, sex ratio and morphometric parameters such as pupal and adult weight, pupal volume, wingspan and head-caudal length were influenced by the host in which the larvae were reared. Sexual maturity, measured as the peak of calling (pheromone emission), was homogeneous on the sixth and seventh days after emergence, but males recovered from fig showed early calling activity on the third day after emergence. The plasticity of C. capitata to adapt its life history traits to specific nutrient variations within the larval environment allows it to colonise and establish populations where key hosts, as those studied here, are available. The knowledge of the interactions between host fruit trees and C. capitata populations provides helpful information for planning the management of local orchards and urban fruit plantations within irrigation oases, taking into consideration the concept of key hosts as peach and fig.

Phosphorus-Mediated Transition from Vegetative to Reproductive Growth in Dwarf Coconut (Cocos nucifera L.).

Reducing the time before the flowering stage in coconut (Cocos nucifera L.) trees greatly influences yield, yet the mechanisms driving the switch from vegetative to reproductive growth are not well understood, especially the role of phosphorus in this transition. In this study, dwarf coconut plants of the same cultivation age were selected and categorized into the vegetative phase (VP) or the reproductive phase (RP). By examining the phenotypic traits, nutrient variations in the roots and soil, and the transcriptional expression of relevant genes in the roots across both phases, we investigated the potential mechanisms driving the transition from the VP to the RP in coconuts. The shoots of coconuts in the RP were significantly taller compared to those in the VP. Moreover, the phosphorus concentration in the roots of coconuts during the RP was 1.31 times higher than in the VP, which may be linked to the significant upregulation of the PT1 genes AZ11G0219160 and AZ02G0034860 in the roots of coconuts in the RP. In addition, all phosphorus-containing metabolites in the roots during the RP showed a significant increase, particularly those related to long-chain fatty acids and ribonucleotide metabolites. This suggests that coconut roots may facilitate the progression from vegetative to reproductive growth by enhancing phosphorus uptake via PT1s and promoting the synthesis and accumulation of phosphorus-containing metabolites.

Effects of Topography on Nutrient Variations in the Western South China Sea

AbstractA topography change in the continental plain plays an important role in nutrient replenishment mechanisms in oligotrophic oceans. Effects of the topography on the nutrient distribution in the western South China Sea (WSCS) have been overlooked since most studies have focused on the dipole‐induced upwelling and downwelling processes of nutrients. We hypothesize that the seamount topography in the northwestern side of the WSCS contributes to the upward distribution of nutrients. We conducted a cruise to investigate the vertical distribution of nutrients in a large area where there is a gradient in the topography: shallow in the north to deep in the south. Our results showed that the depth contours of nutrients, temperature, and salinity shoaled upward from deep to shallow with their isolines being parallel to the bottom depth. The depth of mixed layer, pycnocline, nutricline, and deep chlorophyll maximum showed the similar topographic effect. In the deep water column of 4,308 m deep, integrated NO3− and PO43– over 0–200 m were 879.60 and 81.78 mmol m−2, but increased to 2010.17 and 143.79 mmol m−2 in the shallow water column of 930 m deep, respectively. The increased supply of nutrients enhanced 0–200 m integrated chlorophyll from 21.71 mg m−2 in the deep water column to 51.51 mg m−2 in the shallow water column. These results demonstrate that topographic elevations such as seamounts induce deep‐to‐shallow shoaling and upwelling that lead to enhanced nutrients and biological production in the euphotic zone of oligotrophic oceans.

Disentangling the main factors influencing spring algal blooms in the Three Gorges Reservoir using partial least square structural equation modelling

Eutrophication and the associated algal blooms is a pervasive problem affecting global health, aquaculture, agriculture, water-related industries, and freshwater ecosystems. Spring algal blooms (SABs), which are less common than summer blooms, occur during a time that is thought to be less advantageous due to mild winds, little precipitation, and a relatively small amount of NPS pollutants being transported. Thus, It is pertinent to understand further the factors influencing SABs directly and/or indirectly for improved management. Consequently, Partial least square structural equation modelling (PLS-SEM) was employed to measure the direct and indirect effects of nutrients, lake hydrodynamics (Lake HD), meteorological elements (ME), stratification, Lake Bio-Optics, and Bottom Sediment-Water interaction (BSWI) in Gaoyang Lake of the Three Gorges Reservoir which is characterized by SABs. Based on our findings, total phosphorus (TP) and total nitrogen (TN) together slightly outperformed TP alone in explaining variations in chlorophyll a (chl-a), but the difference was not statistically significant. Thus the parsimonous PLS-SEM model with TP was chosen, and it explained 66.8%, 54.0%, 21.4%, and 59.7% variation in stratification, Lake Bio-Optics, nutrients, and chl-a, respectively. Surprisingly, ME and Lake Bio-Optics had a negative total effect on chl-a during the study. The magnitude of factors influencing SAB occurrence was of the order Lake Hydrodynamics > nutrients > Bottom Sediments-Water Interphase > Lake Bio-Optics > Meteorological Elements > Stratification. This study successfully decoupled and quantified several latent variables’ complex simultaneous causal effects on chl-a.

Seasonal and long-term variations of nutrients in Liaodong Bay, China: Influencing factors and ecological effects

Nutrients are essential for marine primary productivity and have a critical role in maintaining the structure and function of marginal. Variations in nutrient levels in sea ecosystems can influence ecological disturbances significantly. The Liaodong Bay (LDB) is a semi-enclosed marginal sea in northern China. It has experienced severe eutrophication since the 1990s, leading to considerable environmental challenges. Understanding of seasonal and long-term nutrient dynamics in the LDB is limited. We examined seasonal datasets collected in May (spring), August (summer), November (autumn), and March (winter) of 2019, and analyzed long-term trends through historical records spanning multiple decades. Nutrients accumulated during autumn/winter but were depleted during spring/summer. A low concentration of dissolved inorganic phosphate led to an increased nitrogen ratio exceeding the Redfield ratio (>16) during winter, spring, and summer, driven by phytoplankton growth. In late-autumn, nutrient concentrations increased, with ratios approaching the Redfield ratio. Phosphorus limitation prevailed in spring, summer, and winter, while silicon limitation dominated in autumn. Dissolved inorganic nitrogen and nitrogen ratios in the LDB increased sharply since the 1980s, peaking before declining after 2013. Dissolved silica and silicon ratios decreased steadily, stabilizing in recent years. These trends imply a shift from nitrogen-to-phosphorus limitation, influenced by riverine inputs and atmospheric deposition. These nutrient fluctuations may have significant ecological effects, including dinoflagellate abundance, algal blooms, and jellyfish blooms. Our analyses highlight the complexity of nutrient dynamics and positive impact of local nutrient-reduction policies implemented in recent years in improving the environmental quality of the LDB.

Application of SWAT to assess peatland forestry impacts on water quality

ABSTRACT Peatland drainage can affect the natural state of hydrological conditions and nutrient loading but is rarely included in catchment-scale models. To understand the gap, we aimed to use the soil and water assessment tool (SWAT) model to observe drained peatlands and their properties to predict nutrients and suspended solids (SS) in the peatland-dominated Simojoki catchment. We integrated drainage networks in SWAT to (i) identify the parameters for the drainage; (ii) determine annual loads and mean concentrations of SS, organic phosphorus (Org-P), total phosphorus (TP), organic nitrogen (Org-N), and total nitrogen (TN); (iii) understand spatial variation of nutrients and SS; and (iv) investigate the uncertainty ranges for the estimates. The calibrated SWAT model showed a 9.6% PBIAS between the simulated flow and the observations with low to medium loading variations for the water quality parameters. For Org-N and TN, the highest loading per year was at the downstream outlet, whereas for SS, Org-P, and TP, it was higher at the upstream outlet of the catchment. This approach of representing the drained peatland in SWAT indicated a maximum spatial distributed load in the peat soil in the clear-cut area and it can be beneficial in future hydrological modelling efforts in identifying the status of nutrients or SS.

Depth-dependent effects of forest diversification on soil functionality and microbial community characteristics in subtropical forests

Soil microbes are critical to the maintenance of forest ecosystem function and stability. Forest diversification, such as monocultures versus mixed forests stands, can strongly influence microbial community patterns and processes, as well as their role in soil ecosystem multifunctionality, such as in subtropical forest ecosystems. However, less is known about these patterns and processes vary with soil depth. Here, we investigated the results of an eight-year forest diversification field experiment comparing the soil ecosystem multifunctionality, bacterial and fungal community assembly, and network patterns in mixed versus monoculture plantations along vertical profiles (0–80 cm depth) in a subtropical region. We found that the introduction of broadleaf trees in coniferous monocultures led to enhanced synergies between multiple functions, thus improving soil multifunctionality. The effects of mixed plantations on the functional potential in top soils were greater than in deep soils, especially for carbon degradation genes (apu, xylA, cex, and glx). Microbial community assembly in the top layer, particularly in mixed plantations, was dominated by stochastic processes, whereas deterministic were more important in the deep layer. Soil microbial network complexity and stability were higher in the top layer of mixed plantations, but in the deep layer was monoculture. Interestingly, the changes in microbial communities and multifunctionality in the top layer were mainly related to variation in nutrients, whereas those in the deep were more influenced by soil moisture. Overall, we reveal positive effects of mixed forest stands on soil microbial characteristics and functionality compared to that of monocultures. Our findings highlighted the importance of enhancing functional diversity through the promotion of tree species diversity, and managers can better develop forest management strategies to promote soil health under global change scenarios.

The impacts of diet on cardiac performance under changing environments.

Natural and anthropogenic stressors are dramatically altering environments, impacting key animal physiological traits, including cardiac performance. Animals require energy and nutrients from their diet to support cardiac performance and plasticity; however, the nutritional landscape is changing in response to environmental perturbations. Diet quantity, quality and options vary in space and time across heterogeneous environments, over the lifetime of an organism and in response to environmental stressors. Variation in dietary energy and nutrients (e.g. lipids, amino acids, vitamins, minerals) impact the heart's structure and performance, and thus whole-animal resilience to environmental change. Notably, many animals can alter their diet in response to environmental cues, depending on the context. Yet, most studies feed animals ad libitum using a fixed diet, thus underestimating the role of food in impacting cardiac performance and resilience. By applying an ecological lens to the study of cardiac plasticity, this Commentary aims to further our understanding of cardiac function in the context of environmental change.

Does the Reclamation Period Affect the Variation of Soil Nutrients Across Different Vegetation Types in a Reclaimed Opencast Coal Mine Dump? Validated Through Three Soil Sampling Replicates

Does the Reclamation Period Affect the Variation of Soil Nutrients Across Different Vegetation Types in a Reclaimed Opencast Coal Mine Dump? Validated Through Three Soil Sampling Replicates

Spatial Heterogeneity of Soil Nutrient in Principal Paddy and Cereal Production Landscapes of Fengtai County within the Huai River Basin, Eastern China

The problem of cultivated land soil quality in the Huaihe River Basin has become increasingly prominent. How to accurately and quantitatively evaluate the soil quality of regional cultivated land and realize its efficient use has become an urgent problem. In order to explore the spatial autocorrelation and variation in soil nutrients in cultivated land in the plain of Fengtai County in the Huaihe River Basin, a total of 306 soil samples and mature wheat samples were collected in the study area to analyze soil pH, total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), available potassium (AK) and slow-release potassium (SK) content and wheat biomass, and combined with geostatistical methods and GIS technology. The Kriging interpolation method and Moram‘s I index method were systematically analyzed. Principal component analysis (PCA) and Pearson correlation analysis were used to establish the minimum data set (MDS) of soil quality, which was used to calculate the soil quality index (SQI) and determine the key factors affecting soil quality. The results showed that the soil pH was in weak variation, and the other nutrient indexes were in medium variation. The spatial variability of soil-available potassium nutrients was affected by random factors such as human activities and structural factors such as soil parent materials. The spatial autocorrelation of organic matter, total nitrogen, alkali-hydrolyzable nitrogen, available phosphorus, available potassium and mitigation potassium was weak, which was mainly affected by random factors such as human activities. An unequivocal positive spatial nexus was discerned across all nutrients. Cumulatively, the nutrient dispersion across the investigated territory was somewhat diffuse, manifesting in a mosaic pattern with pronounced zonal nutrient allocation disparities in the meridional, median, and septentrional segments. An explicit latitudinal dichotomy delineating zones of nutrient opulence and paucity was also observed. These insights can pave the way for tailored fertilization strategies and judicious pedological stewardship in Fengtai County.

Patterns of Soil Stoichiometry Driven by Mixed Tree Species Proportions in Boreal Forest

Soil stoichiometry is essential for determining the ecological functioning of terrestrial ecosystems. Understanding the stoichiometric relationships in mixed forests could enhance our knowledge of nutrient cycling. In a mixed forest zone of Larix principis-rupprechtii (LP) and Betula Platyphylla (BP) in Hebei China, we conducted a study at six different sites with varying levels of tree species mixing. The proportion of L. principis-rupprechtii ranged from 0% to 100%, with intermediate values of 8.58%, 10.44%, 18.62%, and 38.32%. We compared soil stoichiometry, including carbon (C), nitrogen (N), and phosphorus (P), as well as chemical and physical properties across these sites. Piecewise structural equation modeling (piecewiseSEM) was used to assess the direct and indirect links between key ecosystem factors and their effects on soil stoichiometry. In mixed forests, the soil exhibited higher contents of soil organic matter (SOM), total nitrogen (TN), and total phosphorus (TP) compared to those in pure LP forests. Additionally, the soil C: N ratio in the 8.58% and 18.62% mixed forests as well as pure BP forests was significantly higher than that in LP forests. Structural equation modeling (SEM) revealed that the contents and ratios of soil C, N, and P exhibited different responses to mixed species proportions. The effect of mixed species proportions on soil nutrients was predominantly indirect, mediated primarily by variations in soil-available nutrients and, to a lesser extent, by physical properties and pH. Specifically, an increase in the proportion of LP in mixed forests had a direct negative effect on soil-available nutrients, which in turn had a positive effect on the content of SOM, TN, and TP and their respective ratios. Based on these findings, we can predict that soil nutrient limitation becomes more pronounced with increasing proportions of Larix principis-rupprechtii in the mixed forest. Our results emphasized the significance of changes in mixed species proportions on soil stoichiometry, providing valuable references for the sustainable development of forests.

Seasonal variation of sedimentary nutrients and litter production in the mangrove ecosystem of indian sundarban: Implications for ecosystem dynamics

Seasonal variation of sedimentary nutrients and litter production in the mangrove ecosystem of indian sundarban: Implications for ecosystem dynamics

Factors Affecting Seedling Growth Performance and Quality of Two A<i>cacia Species and Shinus Molle </i>on Nursery Stage, Southern Oromia, Ethiopia

The study was carried out within the Nursery of the Department of Forestry, at Sinana Agricultural Research Center, on the effects of different soils media and varying pot sizes on the early growth of <i>Acacia abyssinica, Acacia saligna and Shinus molle </i>were investigated. Four different soils media used were forest soil (FS), compost (Co), sand soil (SS) and local soil (LS) in different pots size (PS1=8 cm=control, PS2=10 cm and PS3=12 cm lay flats) 15 cm in length and five growing media (GM) or soil mix proportion based on volume GM1= (2 part local/Top soil:2 part forest soil:1 part sand; GM2=2 part local soil:2 compost: 1 part sand; GM3=1 part local soil:2 part forest soil:2 part sand; GM4=3 part local soil:2 part compost:1 sand soil and GM5=3 local soil:2 forest soil:1 sand=control) were filled up of different types of soil named above, and quantified using weighing balance. The experiment was laid out in Randomized Complete Block Design (RCBD) at the Forestry nursery in the study area. The study involved the use of five (5) planting media and three different plastic pots in three (3) replicates. The parameters measured are plant height (cm), seedling root collar diameter (mm) and dry matter (shoot, root and root to shoot ratio). The data collected at the end of twenty weeks were subjected to Analysis of Variance (ANOVA) and means were separated using Duncan test showed that <i>Schinus molle, A.abyssinica </i>and<i> A.saligina</i> tree species plant and grown in large pot size (PS2) and growing media (GM3) had the highest performance with mean value of plant height 19.83cm, 7.833cm and 13.167cm and seedling root collar diameter in GM5PS3 (4.09mm), GM4PS3 (3.35mm) and GM4PS1 (3.97mm) respectively were high significantly (P< 0.05). It is therefore recommended that large pot size (PS3) and GM2 and GM3growing media be used for optimal production of all <i>Schinus molle, A.abyssinica </i>and<i> A.saligina </i>tree species seedling production at nursery stage and their plantation success. This study revealed that optimum ratio of compost and forest soil in growing media and relatively big container/pot size have favorable good quality of seedling growth for all studied tree species for all growth parameters. This is may be due to nutrient variation in the growing media which is farther needs investigation on growing media nutrients contents.

Contrasting Dynamics of Intracellular and Extracellular Antibiotic Resistance Genes in Response to Nutrient Variations in Aquatic Environments.

The propagation of antibiotic resistance in environments, particularly aquatic environments that serve as primary pathways for antibiotic resistance genes (ARGs), poses significant health risks. The impact of nutrients, as key determinants of bacterial growth and metabolism, on the propagation of ARGs, particularly extracellular ARGs (eARGs), remains poorly understood. In this study, we collected microorganisms from the Yangtze River and established a series of microcosms to investigate how variations in nutrient levels and delivery frequency affect the relative abundance of intracellular ARGs (iARGs) and eARGs in bacterial communities. Our results show that the relative abundance of 7 out of 11 representative eARGs in water exceeds that of iARGs, while 8 iARGs dominate in biofilms. Notably, iARGs and eARGs consistently exhibited opposite responses to nutrient variation. When nutrient levels increased, iARGs in the water also increased, with the polluted group (COD = 333.3 mg/L, COD:N:P = 100:3:0.6, m/m) and the eutrophic group (COD = 100 mg/L, COD:N:P = 100:25:5, m/m) showing 1.2 and 3.2 times higher levels than the normal group (COD = 100 mg/L, COD:N:P = 100:10:2, m/m), respectively. In contrast, eARGs decreased by 6.7% and 8.4% in these groups. On the other hand, in biofilms, higher nutrient levels led to an increase in eARGs by 1.5 and 1.7 times, while iARGs decreased by 17.5% and 50.1% in the polluted and eutrophic groups compared to the normal group. Moreover, while increasing the frequency of nutrient delivery (from 1 time/10 d to 20 times/10 d) generally did not favor iARGs in either water or biofilm, it selectively enhanced eARGs in both. To further understand these dynamics, we developed an ARGs-nutrient model by integrating the Lotka-Volterra and Monod equations. The results highlight the complex interplay of bacterial growth, nutrient availability, and mechanisms such as horizontal gene transfer and secretion influencing ARGs' propagation, driving the opposite trend between these two forms of ARGs. This contrasting response between iARGs and eARGs contributes to a dynamic balance that stabilizes bacterial resistance levels amid nutrient fluctuations. This study offers helpful implications regarding the persistence of bacterial resistance in the environment.

Assessing LDPE microplastics' impact on green gram (Vigna radiata L. Wilczek) cultivation: A greenhouse pot experiment

Plastic pollution, particularly from microplastics (MPs), poses a significant threat to agricultural ecosystems. This study investigates the impact of Low-Density Polyethylene (LDPE) microplastics on green gram (Vigna radiata) cultivation, focusing on growth, yield, and soil nutrient dynamics. A completely randomized design with nine treatments of varying LDPE concentrations was used in a controlled poly house environment. Soil analysis assessed mechanical and physico-chemical properties using established methods. Green gram variety Co (Gg) 8 was cultivated during the Rabi season, with comprehensive crop management including germination tests, pot culture preparations, precise fertilizer application, and essential cultural operations. Results indicated significant correlations between LDPE concentrations and green gram growth parameters, with higher concentrations having detrimental effects (correlation coefficient = −0.75, p < 0.05). LDPE treatments also influenced plant nutrient uptake, showing inverse correlations with nitrogen (N), phosphorus (P), and potassium (K) uptake (correlation coefficient = −0.82, p < 0.01). Post-harvest soil analysis revealed significant variations in available nutrients, with LDPE-treated soils exhibiting higher N, P, and K levels compared to control groups (correlation coefficient = 0.78, p < 0.01). Infrared spectroscopy confirmed the presence of LDPE microplastics in soil and plant samples, identified by characteristic (CO) and (C–H) stretching vibrations. These findings highlight the complex interactions between LDPE microplastics and agricultural systems, emphasizing the need for sustainable practices to mitigate the adverse effects of plastic pollution on agriculture. Statistical analysis using the CRD framework and correlation and regression analyses ensured robust interpretation of the data.