Low Nutrient Research Articles

Influence of Spacing and Weed Management Practices on the Growth Characters, Nutrient Removal of Weeds and Nutrient Uptake of Direct Seeded Rice

Background: The field experiment was conducted at the Anbil Dharmalingam Agricultural College and Research Institute, Tiruchirappalli, Tamil Nadu during rabi, 2022-2023 to study the influence of spacing and weed management practices on growth characters, nutrient removal by weeds and nutrient uptake of direct seeded rice (DSR). Methods: The field experiment was laid out in split plot design with three replications. The main plots were spacing of 20 × 15 cm, 20 × 20 cm and 25 × 25 cm. Sub plots were assigned with weed management practices viz., pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + bispyribac sodium 10% SC at 25 g a.i ha-1 on 20 DAS as PoE, Pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Cono weeding on 20 DAS + hand weeding (HW) on 40 DAS, Pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Cono weeding on 20 DAS and 40 DAS, Pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Bispyribac sodium 10% SC at 25 g a.i ha-1 on 20 DAS as PoE + Cono weeding on 40 DAS, Pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Bispyribac sodium 10% SC at 25 g a.i ha-1 on 20 DAS as PoE + Hand weeding on 40 DAS, Hand weeding at 20 and 40 DAS and unweeded control. Result: The results indicated that the highest growth attributes, higher nutrient uptake of nitrogen, phosphorous and potassium under DSR and were significantly improved by spacing 20 × 20 cm along with pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Bispyribac sodium 10% SC at 25 g a.i ha-1 on 20 DAS as PoE + Cono weeding on 40 DAS. This was on par with pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Bispyribac sodium 10% SC at 25 g a.i ha-1 on 20 DAS as PoE + Hand weeding on 40 DAS and hand weeding on 20 and 40 DAS. Similarly lower nutrient removal by weeds were registered under 20 × 15 cm spacing along with pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Bispyribac sodium 10% SC at 25 g a.i ha-1 on 20 DAS as PoE + cono weeding on 40 DAS. The interaction of spacing 20 × 20 cm and pyrazosulfuron ethyl 10% WP at 20 g a.i ha-1 on 3 DAS as PE + Bispyribac sodium 10% SC at 25 g a.i ha-1 on 20 DAS as PoE + Cono weeding on 40 DAS significantly increased the growth attributes such as plant height, dry matter production and total numbers of tillers and significantly lowered the nutrient removal by weeds.

Additive effects of two agri-environmental schemes on plant diversity but not on productivity indicators in permanent grasslands in Switzerland

Different agri-environmental schemes (AES), such as ecological focus areas and organic farming, have been suggested to reduce the impact of intensive agriculture on the environment and to conserve or even restore farmland biodiversity. However, the effectiveness of such schemes, their ability to actually support biodiversity and associated trade-offs with agricultural production are still debated. We analysed a large dataset from the biodiversity monitoring in the Swiss agricultural landscape to assess the effects of two different grassland AES, i.e., extensively managed ecological focus areas (EFAs versus non-EFAs) and organic farming (versus conventional), on plant diversity, plant community composition and productivity indicators, i.e., weed abundance, forage value and nutrient availability. We also considered environmental factors, i.e., topography and soil conditions, which potentially modulate AES effects on biodiversity. We used in total 1170 plots in permanent grasslands, managed as meadows or pastures.Both AES had significant positive effects on plant diversity. However, EFAs increased plant richness considerably stronger (+6.6 species) than organic farming (+1.8 species). Effects of the two schemes were additive with organic EFA grasslands exhibiting highest plant diversity. Differences in topography partly explained AES effects on diversity as both AES were associated with differences in elevation and slope. Thus, future assessments of the effectiveness of AES need to consider the non-random placement of AES across heterogeneous landscapes. EFA grasslands revealed a considerably reduced agricultural productivity as shown by low forage values and low nutrient availability. Yet, the abundance of agricultural weeds, i.e., agriculturally undesired plant species, was lower in EFA compared to non-EFA grasslands. Productivity indicators were only weakly affected by organic farming and other than for plant diversity, productivity did not differ between organic and conventional EFA grasslands.The positive additive diversity effects of EFAs and organic grassland farming underline the potential of both AES to contribute to biodiversity conservation in agricultural landscapes, though to a different extent. Comparing the effects of the two AES revealed that the lower the reduction in agricultural productivity associated with an AES, the smaller the gains in plant diversity, highlighting the inevitable trade-off between productivity and plant diversity in semi-natural grasslands.

Immune inhibitory receptor-mediated immune response, metabolic adaptation, and clinical characterization in patients with COVID-19

Immune inhibitory receptors (IRs) play a critical role in the regulation of immune responses to various respiratory viral infections. However, in coronavirus disease 2019 (COVID-19), the roles of these IRs in immune modulation, metabolic reprogramming, and clinical characterization remain to be determined. Through consensus clustering analysis of IR transcription in the peripheral blood of patients with COVID-19, we identified two distinct IR patterns in patients with COVID-19, which were named IR_cluster1 and IR_cluster2. Compared to IR_cluster1 patients, IR_cluster2 patients with lower expressions of immune inhibitory receptors presented with a suppressed immune response, lower nutrient metabolism, and worse clinical manifestations or prognosis. Considering the critical influence of the integrated regulation of multiple IRs on disease severity, we established a scoring system named IRscore, which was based on principal component analysis, to evaluate the combined effect of multiple IRs on the disease status of individual patients with COVID-19. Similar to IR_cluster2 patients, patients with high IRscores had longer hospital-free days at day 45, required ICU admission and mechanical ventilatory support, and presented higher Charlson comorbidity index and SOFA scores. A high IRscore was also linked to acute infection phase and absence of drug intervention. Our investigation comprehensively elucidates the potential role of IR patterns in regulating the immune response, modulating metabolic processes, and shaping clinical manifestations of COVID-19. All of this evidence suggests the essential role of prognostic stratification and biomarker screening based on IR patterns in the clinical management and drug development of future emerging infectious diseases such as COVID-19.

Responses of soil reactive nitrogen pools and enzyme activities to water and nitrogen levels and their relationship with apple yield and quality under drip fertigation

Improper water and nitrogen supply can lead to resource loss, soil quality deterioration, low nutrient effectiveness, and decreased fruit yield and quality in apple orchards. To investigate the soil nitrogen characteristics and enzyme activities in drip-fertigated apple orchards on the Loess Plateau and their relationship with fruit yield and quality formation, field experiments were conducted on dwarf Fuji apple from 2017 to 2022. The experiment consisted of two factors, including two irrigation levels (W) and four nitrogen rates (N) applied. Irrigation was set to two upper irrigation limit levels based on soil moisture, 85 % (W1) and 100 % (W2) of field capacity (FC), and the nitrogen rates were 0 (N1), 120 (N2), 240 (N3) and 360 (N4) kg ha−1. The results showed that irrigation and nitrogen rates had significant effects on soil mineral nitrogen, soluble organic nitrogen (SON), microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN), enzyme activity, and apple yield and quality. At W1, the proportion of soil NO3−-N to the total soluble nitrogen (TSN) pools increased with increasing nitrogen rates, and NO3−-N gradually replaced SON as the main form of TSN. The responses of MBC and MBN to nitrogen rates were different at different irrigation levels. Apple yield and total soluble solids (TSS), soluble sugar (SS) and vitamin C (VC) contents first increased and then decreased with increasing nitrogen application. Ridge regression analysis showed that SON was the most important factor affecting apple yield, followed by MBN. The VC and TSS contents were most affected by soil urease and sucrase, respectively. The comprehensive evaluation by the TOPSIS method ranked W1N3 as the first and optimal treatment, which can achieve high fruit yield and quality while improving soil nitrogen nutrition and biological characteristics to attain sustainable apple farming.

Soil organic carbon stocks and belowground biomass in patches in heterogeneous grassland

AbstractBackgroundSelective grazing creates stable patches of contrasting sward height, thereby providing different growth conditions for the grass sward above and below ground and potentially affecting soil organic carbon (SOC) stocks. We hypothesized that the presence of patches leads to greater spatial variability in belowground biomass (BGB) and SOC stocks than occurs between pastures managed under different stocking intensities.MethodsA long‐term grazing experiment consisting of three stocking intensities was used for this study. We studied BGB, SOC, and soil total nitrogen (Ntot) stocks in the 0–15 cm soil depth. Shannon diversity of plant species, soil bulk density, soil phosphorus, potassium, and magnesium contents were considered.ResultsThere were no significant effects of patch or stocking intensity on BGB, SOC, and Ntot stocks. Short patches had a greater Shannon diversity than tall patches (p < 0.05) and plant‐available nutrients in soil correlated positively with sward height (p < 0.05).ConclusionsWe conclude from the current results and previous studies that higher plant species diversity with lower soil nutrient contents in short‐patch areas and higher nutrient contents together with light competition in tall‐patch areas might balance each other out with respect to BGB and SOC stocks.

Milled rapeseeds and oats decrease milk saturated fatty acids and ruminal methane emissions in dairy cows without changes in product sensory quality

Plant lipids in the diet are known to modify milk fatty acid (FA) composition and mitigate ruminal methane emissions. The objective of the present work was to examine the potential of milled rapeseeds and oats to decrease both milk saturated FAs and ruminal methane emissions in practical farm settings. In the pilot study, six Finnish Ayrshire cows were fed a control diet for 3 weeks, which was then followed by a lipid-rich test diet for 3 weeks. The experimental diets were based on grass silage supplemented with barley and rapeseed meals in the control diet and with oats and milled rapeseeds in the test diet. The lipid inclusion rate was 55 g/kg dry matter (DM). In the main study, the whole Finnish Ayrshire research herd in milk (n = 49–59) was used in a switch-back-designed study. The cows were fed a control diet for 3 weeks, then a test diet for 4 weeks, and, finally, a control diet for 3 weeks. The diets were the same as in the pilot study except for a lower lipid inclusion level of 50 g/kg DM. The test diet decreased DM intake by 15% and energy-corrected milk (ECM) yield by 13% in the pilot study. The adjustment of supplemental lipids from 55 g/kg to 50 g/kg DM was successful, as the DM intake decreased only by 4% relative to the control diet in the main study. Furthermore, the yields of milk, lactose, protein, and fat were also unaffected by dietary lipids in the main study. The milk fat composition was significantly altered in both studies. The milk fat saturated FAs were decreased by 16%–20% in the test diet, mainly due to the de novo FAs of 6- to 16-carbons (a reduction of 22%–48%). Milk fat cis-9 18:1 was increased by 63%–78% in the test diet relative to the control. Dairy products’ (milk, butter, and cheese) organoleptic quality was not compromised by the modified lipid profile. Ruminal methane and hydrogen intensities (n = 23; g or mg/kg ECM) were 20% and 39% lower, respectively, in the test diet than in the control diet. This reduction can be attributed to a lower amount of organic matter fermented in the rumen, as indicated by the lower DM intake and nutrient digestibility.

Soil nutrient levels regulate the effect of soil microplastic contamination on microbial element metabolism and carbon use efficiency

Microplastics (MPs) are emerging environmental contaminants in soil ecosystems that disrupt the soil carbon (C) pool. Therefore, the response of microbial metabolism to MP-contaminated soil is crucial for soil-C stabilization. We undertook factorial experiments in a greenhouse with three types of soil microplastics with three levels of soil nutrients and undertook soil physiochemical analyses after 60 days. The present study revealed how the presence of degradable polylactic acid (PLA) and non-degradable polyethylene (PE) MPs affects soil microbial nutrient limitation and C use efficiency (CUE) at varying nutrient concentrations. The presence of PLA in soil with low nutrient levels led to a significant increase (29%) in the activities of nitrogen (N)-acquiring enzymes. In contrast, the presence of MPs had no effect on C- and N-acquiring enzymes. The occurrence of PE caused a 41% reduction in microbial C limitation in high-nutrient soils, and microbial nutrient metabolism was limited by the occurrence of MPs in soils amended with nutrients. A strong positive correlation between microbial C and nutrient limitation in the soil indicates that addressing C limitation followed by amendment of soil with MPs could potentially intensify microbial N limitation in soils with varying nutrients. In comparison, the microbial CUE increased by 10% with the application of degradable MPs (PLA) to soils with a low nutrient status. These findings highlight the significant influence of both degradable PLA and non-degradable PE MPs on soil microbial processes and C dynamics. In conclusion, PLA enhances metabolic efficiency in nutrient-rich soils, potentially aiding C utilization, whereas PE reduces microbial C limitation, offering promise for soil C sequestration strategies. Our findings underscore the importance of considering MPs in soil ecosystem studies and in broader sustainability efforts.

Species preference for seagrass restoration using vertical distribution model in Tidung Island, Indonesia

Tidung Island is one of the small inhabited islands and a tourist destination that allows the degradation of seagrass meadow and requires physical restoration using transplantation techniques. The seagrass species’ preference suitability needs to assess with this island for this case. This study aims to provide information on species that are possible to choose in seagrass transplantation based on their growth zones. The number of seagrass species, depths, and types of substrates was taken using seagrasswatch guideline by line transects along the coast to the reef slope with 10% plot intervals from the total length of the transect. Seagrass growth is divided into three zones: near the coast (back), middle, and near the reef slope (front). Enhalus acoroides, Cymodocea rotundata, and Thalassia hemprichii were found in almost all zones. Halophila ovalis, Halophila minor, and Halodule uninervis were distributed in the middle to front zone, while Syringodium isoetifolium was only in the middle zone. These findings suggest that transplant areas with high anthropogenic disturbances can use Enhalus acoroides and Thalassia hemprichii because they have the persistent trait. Meanwhile, the areas with low anthropogenic disturbance and low nutrients can use Halophila spp. and Halodule spp., because they can grow shoots and recover quickly.

The Adaptation of Ciherang Rice Variety Roots to Various Levels of Low Nutrient Stress in Tidal Swamp Soils

Rice cultivation in tidal land has many abiotic stresses. One of them is low nutrient stress. This research aims to determine and study the adaptation of rice roots to various levels of low nutrient stress in tidal swamp soil. These research was carried out from September 2016 to May 2017 at the Experimental Garden, Laboratory of Botany and Plant Physiology of Faculty of Agriculture of IBA University in Palembang, South Sumatra Province. These experiment used a Randomized Block Design with three replications and four low nutrient levels. The treatments are: N1 = 40% Fertilization dose (FD, N2 = 50% FD, N3 = 60% FD and N4 = 100% FD. The 100% FD is 300 kg urea. ha-1, 100 kg SP-36.ha-1 and 150 kg KCl.ha-1. These research used Ciherang rice varieties that planted in pots containing 12 kg of tidal swamp soil type B from Bunga Karang Village, Tanjung Lago District, Banyuasin Regency, South Sumatra Province, Indonesia. The results showed that low nutrient stress increased root length, root weight, root length density, root weight density, root weight ratio and number of tillers, but reduced crown weight and panicle weight per clump

Nutrient Uptake in Different Maize Varieties (Zea mays L.) Planted in Tropical Peat Materials

Oligotrophic tropical peat soils are usually deemed unsuitable for cropping common crops such as maize due to low pH and nutrient deficiency. This research aims to compare potassium, calcium, and magnesium uptake between different varieties of maize planted in two types of peat materials. This study investigated the growth of selected maize varieties by comparing the nutrient uptake between three different varieties of maize (V1-Asia Manis, V2-Super A, and V3-Pearl Waxy) planted on hemic and sapric, respectively, without any application of fertilisers. Significant interactions were found where different maize varieties responded differently in the nutrient uptake when planted in different peat materials. Super A (V2) significantly recorded the highest uptake for all nutrients (679.71 mg) when planted in hemic, followed by V1 (422.03 mg) and V3 (314.77 mg) when planted in sapric. Super A was found to be superior to the two varieties, where it was more efficient in absorbing nutrients from the peat materials, having significantly higher dry matter weight (26.37 g) than V1 (19.26 g) and V3 (13.67 g). Hemic and sapric could support the growth of all three maize varieties up till the tasselling stage without any fertiliser application.

Understanding the agronomic impacts of defoliation strategies in “Bulldog 805” Alfalfa + “Tifton 85” bermudagrass mixed stands

AbstractBackgroundThe incorporation of legumes, specifically alfalfa (Medicago sativa L.), into bermudagrass (Cynodon spp.)‐based pasture systems in the southeastern United States has increased in recent years as an alternative to synthetic nitrogen (N) fertilization.MethodsA small plot evaluation was conducted in Shorter, Alabama, and Tifton, Georgia, USA, to evaluate the impact of harvest height (HH) and harvest frequency (HF) on agronomic characteristics of alfalfa+bermudagrass mixtures in southeastern United States.ResultsResults from both locations revealed that the longer the HF and the shorter the HH, the greater the alfalfa retention was in the stand (p < 0.01). HH did not impact any of the reported nutritive value parameters, while longer HF resulted in lower total digestible nutrients, lower crude protein, higher acid detergent fiber, and lower 48 h in vitro dry matter digestibility (p < 0.01). Both HH and HF impacted forage accumulation at both locations (p < 0.01). HH resulted in different trends at each location, while longer frequencies generally increased forage accumulation.ConclusionsThis research confirmed recent findings from comparable evaluations in the southeastern United States, in that increasing HH and decreasing HF improved alfalfa retention while having a negligible effect on nutritive value or forage accumulation.

Effects of Three Long-Term Land Use Patterns on Soil Degradation in the Yellow River Delta: Evidence from Ecological Stoichiometry

The irrational land use patterns in the Yellow River Delta (YRD) have resulted in an imbalance in ecological stoichiometry, leading to secondary salinization and soil degradation. However, there is limited knowledge about the long-term response of soil and enzyme stoichiometry to land use. This hampers our ability to optimize land use in the YRD to alleviate nutrient limitation and thus promote ecological stoichiometric balance. We investigated the stoichiometry of soil and enzyme carbon (C), nitrogen (N), and phosphorus (P) in three land use patterns (Alfalfa artificial grassland, AG; wheat–maize rotation field, WM; native grassland, PC) established for 19 years in the YRD. The results showed that the soil stoichiometry of the three land uses in the YRD was lower than the world and Chinese averages, indicating lower C and N levels. Nutrient limitations of soil microorganisms were C and P due to an enzyme C:N ratio greater than 1:1 and vector angle greater than 45°. The three land use patterns have different advantages in alleviating nutrient limitations in the YRD. AG promotes soil macroaggregate formation, reduces soil salt content, improves nutrient availability, and mitigates N limitation. This makes AG more conducive to improving the poor soil structure, high soil salinity, and stoichiometric imbalance in the YRD to mitigate local soil degradation and be suitable for long-term continuous cultivation. WM is beneficial for increasing soil total C content due to straw return. However, WM does not reduce soil salinity. WM is more suitable for intercropping or crop rotation to improve soil C content in the YRD. Although PC can alleviate soil microbial C limitation due to its significantly lower vector length than AG and WM, the low nutrient levels hindered its ability to alleviate local soil nutrient limitation. In conclusion, our study provides a theoretical basis for rational land use in the YRD to mitigate soil degradation.

Decadal Variability in Subsurface Nutrient Availability on the Scotian Shelf Reflects Changes in the Northwest Atlantic Ocean

AbstractSubsurface nutrients on the Scotian Shelf, an ocean region at the convergence of the subpolar and subtropical western boundary currents (i.e., Labrador Current (LC) and Gulf Stream (GS)), are chiefly modulated by upstream shelf and slope waters. Yet little is known about long‐term fluctuations in the advective transport of nutrients to the shelf. Here, we synthesized nutrient and hydrographic data from 1975 to 2020 to characterize decadal changes in upper (60–150 m) and lower (150–200 m) subsurface nutrient availability across the shelf. Hydrographic and nutrient anomalies highlight a transition from a warm, saline, high‐nutrient GS‐dominated system in the 1980 to colder, fresher, lower‐nutrient LC‐dominated conditions in the late 1980 and early 1990. In the mid‐1990, an increase in excess silicate and phosphate (relative to nitrate) marks a shift in the LC contribution toward a strengthening of the inner shelf component relative to the outer shelf‐edge branch. Since 2010, rapid increases in subsurface temperature and salinity indicate the transition back to a GS‐dominated system, albeit with a distinct decline in dissolved nutrients relative to the previous warm period, which diverges from the nutrient increase generally associated with GS water. Declines in lower subsurface nutrient concentrations since 2010 are likely driven by a density‐related shift in the GS source water toward a less dense, lower‐nutrient GS contribution. This shift is evidenced by a decrease in excess phosphate amidst minor declines in excess silicate, reflecting the characteristic density‐related patterns of excess nutrients in GS waters.

Landscape-based nutrient application in wheat and teff mixed farming systems of Ethiopia: farmer and extension agent demand driven approach

IntroductionAdapting fertilizer use is crucial if smallholder agroecosystems are to attain the sustainable development goals of zero hunger and agroecosystem resilience. Poor soil health and nutrient variability characterize the smallholder farming systems. However, the current research at the field scale does not account for nutrient variability across landscape positions, posing significant challenges for targeted nutrient management interventions. The purpose of this research was to create a demand-driven and co-development approach for diagnosing farmer nutrient management practices and determining landscape-specific (hillslope, mid-slope, and foot slope) fertilizer applications for teff and wheat.MethodA landscape segmentation approach was aimed to address gaps in farm-scale nutrient management research as well as the limitations of blanket recommendations to meet local nutrient requirements. This approach incorporates the concept of interconnected socio-technical systems as well as the concepts and procedures of co-development. A smart mobile app was used by extension agents to generate crop-specific decision rules at the landscape scale and forward the specific fertilizer applications to target farmers through SMS messages or print formats.Results and discussionThe findings reveal that farmers apply more fertilizer to hillslopes and less to mid- and foot slopes. However, landscape-specific fertilizer application guided by crop-specific decision rules via mobile applications resulted in much higher yield improvements, 23% and 56% at foot slopes and 21% and 6.5% at mid slopes for wheat and teff, respectively. The optimized net benefit per hectare increase over the current extension recommendation was $176 and $333 at foot slopes and $159 and $64 at mid slopes for wheat and teff (average of $90 and $107 for wheat and teff), respectively. The results of the net benefit-to-cost ratio (BCR) demonstrated that applying landscape-targeted fertilizer resulted in an optimum return on investment ($10.0 net profit per $1.0 investment) while also enhancing nutrient use efficiency across the three landscape positions. Farmers are now cognizant of the need to reduce fertilizer rates on hillslopes while increasing them on parcels at mid- and foot-slope landscapes, which have higher responses and profits. As a result, applying digital advisory to optimize landscape-targeted fertilizer management gives agronomic, economic, and environmental benefits. The outcomes results of the innovation also contribute to overcoming site-specific yield gaps and low nutrient use efficiency, they have the potential to be scaled if complementing innovations and scaling factors are integrated.

Occurrence of mycotoxins, phytoestrogens and other fungal metabolites in Ready-to-Use Therapeutic Foods for severely and acutely malnourished children

Ready-to-Use Therapeutic Foods (RUTFs) are mainly legumes- or nut-based low moisture, high energy and nutrient dense ready-to-eat foods strictly designed to treat severe acute malnutrition (SAM) in children. Despite the critical application of this food in a highly vulnerable population, there is no information on the spectrum of mycotoxins in RUTFs globally. This study therefore assessed 41 RUTF samples available in northern Nigeria for multiple mycotoxins using LC-MS/MS. Sixteen mycotoxins and 31 other metabolites comprising phytoestrogenic phenols, plant toxins and metabolites from diverse fungi were detected in the RUTF samples. The mycotoxins include aflatoxin B1 (AFB1), citrinin (CIT), deoxynivalenol, enniatins, alternariol methyl ether, moniliformin, sterigmatocystin, zearalenone, and their derivatives. AFB1 was detected in 5% of the samples at concentrations below the Codex Alimentarius maximum limit of 5 μg/kg, but exceeded the stricter 0.1 μg/kg European Union limit for baby/infant foods by 4–19 times. The highest mean mycotoxin concentration (42 μg/kg) was recorded for CIT, whereas enniatin B was the most occurring (73%). For other metabolites, abscisic acid and cordycepin were the most frequently occurring (100%), while genistin, a phytoestrogenic isoflavone, had the highest mean of 15,751 μg/kg. RUTF from composite flour blends had more mycotoxins compared to those made from peanuts. This is the first study on mycotoxin occurrence in RUTFs. Further studies are needed to assess the presence of mycotoxins and other metabolites in RUTFs on a larger scale as well as the associated risks from their occurrence in view of the high vulnerability of SAM children who consume the foods.

Nitrogen and Phosphate Content as Indicators of Eutrophication Level around the Mandalle Beach, Pangkep Regency, Indonesia

Coastal areas, including the coast of Mandalle Beach, are areas that range in the occurrence of pollution, including eutrophication. The research aims to determine the level of eutrophication on the coast of Mandalle Beach based on indicators of nitrogen and phosphate content in the waters. The research was carried out for three months, namely April to June 2023. The research was conducted at five research locations, namely location 1, adjacent to fish cultivation and seaweed cultivation areas; location 2, adjacent to the Pangkep State Agricultural Polytechnic pier; location 3, adjacent to a mangrove forest; and location 4, located at the mouth of a small river and directly related to the sea and location 5, namely the location around the Mandalle traditional market and near the rice fields. Determining the location of the sampling is done by non-probability sampling. The data collected is on total nitrogen and total phosphate content. Data was collected by taking water samples, which were then brought to the laboratory for analysis. The data analysis used is descriptive analysis. The results showed that the total nitrogen content in the study was in the mesotropic tropic status, which was ≤ 0.750 ppm. Phosphate content at locations 1, 2, 4, and 5 entered the tropic status of the oligotrophic category, namely <0.010 ppm, while location 3 entered the tropic status of the mesotrophic category. Thus, the coast of Mandalle Beach is at a moderate fertility level with low nutrient content, so it can be stated that based on the elements N and P, the waters of Mandalle Beach have not yet experienced eutrophication.

Eocene-Oligocene large-scale circulation of the East Asian summer monsoon recorded in neritic carbonates of the proto-South China Sea

When the modern features of large-scale Asian monsoonal circulation were set-up is poorly constrained and pre-Neogene monsoonal archives are rare. This study investigates the temporal evolution of neritic carbonates in the proto-South China Sea to reconstruct East Asian monsoonal currents and winds during the middle to late Paleogene. Analysis of three-dimensional seismic and well core data from the North-West Palawan block reveals the occurrence of a set of thick (>125 m), aggrading Halimeda bioherms, early Oligocene in age. By analogy with Holocene green algal buildup counterparts, they are interpreted to form in nutrient-rich areas subject to upwelling currents and reflect the early presence of a strong coastal jet in the Proto-South China Sea, as seen today during the summer monsoonal season. The analysis of the underlying mixed carbonate–siliciclastic ramp shows that mesotrophic conditions already prevailed during the late Eocene, thus suggesting that modern-like summer East Asian Monsoon large-scale circulation was possibly active as early as the late Eocene in the Proto-South China Sea. Evidence for upwelling currents vanishes in late early Oligocene carbonate-producing biota, that are characterized by the significant development of euphotic hermatypic coral communities reflecting lower nutrient concentrations. This turnover coincides with the opening of the modern South China Sea and is interpreted to result from the southward drift of the North-West Palawan block which placed the area away from the Chinese margin and the coastal jet. Our results highlight therefore that many of the features of the summer East Asian Monsoon large-scale circulation are rooted in the middle Paleogene.

A test of island plant syndromes using resource‐use traits

AbstractDespite representing a fraction of the global terrestrial surface area, oceanic islands are disproportionately diverse in species, resulting from high rates of endemicity. Island plants are thought to share a unique phenotype—referred to as an island syndrome—which is thought to be driven by convergent evolution in response to selection by shared abiotic and biotic factors. One aspect of the island plant syndrome that has received relatively little research focus is that island plants are expected to have converged on conservative resource use associated with slow growth rates and weak competitive abilities. Here we tested whether native, woody Hawaiian plant species are phenotypically distinct—with more resource‐conservative leaf traits—compared to a globally distributed sample of continental species. Using an archipelago‐wide trait data set, we detected that on average, native Hawaiian species had lower leaf nutrient concentrations overall, and lower nutrient concentrations at high leaf mass per area, but no other phenotypic differences compared with continental plants. There was also considerable overlap in the trait spaces of native Hawaiian species and continental species. Our findings indicate that an island plant syndrome for leaf traits is not present in the Hawaiian flora, and that island species can demonstrate extensive variation in their resource‐use strategies, on a scale that is comparable with that of continental species worldwide.

PSIV-1 Nutrient Intervention During Gilt Development Leads to Effects on Progeny Growth Responses

Abstract To elucidate the effect of early life dietary nutrient level and vitamin D source during gilt development on progeny growth performance, equal number of weaning age piglets (n = 72) were selected from each of 4 sow treatments group. All pigs were fed a common 3,000 ppm zinc diet for first two weeks postweaning to allow for accommodating the weaning process. At the beginning of week 3, pigs were sorted by sow parity and BW within gender and stratified based on maternal dietary treatments. Dietary treatments during gilt development period included two levels of dietary nutrients (Adeq: optimal growing diet that exceed NRC 2012 recommendation or Low: moderate slow growing diet that SID lys and ME levels were gradually reduced by 0.03% and 0 kcal/kg, 0.15% and 146 kcal/kg, and 0.15% and 150 kcal/kg, respectively) and two sources of vitamin D [StD: 1653 IU cholecalciferol/kg or HyD: 500 IU cholecalciferol/kg + 50 mcg calcifediol (ROVIMIX HY.D DSM Nutritional Products North America)] during development phase 1 (23 to 57 kg), 2 (57 to 91 kg), and 3 (91 until breeding). Dietary nutrient level treatment was withdrawn during gestation and lactation stages, while sows remained on their vitamin D treatments. Progeny were fed with a 6-phase feeding regimen as nursery phase 3 (14 d) and 4 (14 d), grower phase 1 (28 d) and 2 (28 d), and finisher phase 1 (28 d) and 2 (28 d). All pigs were transferred to a commercial processing plant where carcass characteristics were measured. Data were analyzed using Mixed procedure of SAS (Cary, NC) with maternal diet nutrient level, vitamin D source and the interaction as fixed effects. Progeny born from sows fed HyD diets had greater ADG in overall grower/finisher phases (P = 0.04) and during the whole trial (P = 0.03). This weight gain improvement increased the final BW, HCW, and yield percentage over StD derived progeny by 3.19 kg, 3.56 kg and 0.11% (P = 0.04, 0.02 and < 0.01), respectively. Dietary nutrient level had limited effect on progeny ADG and BW during the preslaughter period. The maternal vitamin D source did not affect progeny ADFI but overall G:F tended (P = 0.06) to be greater in pigs sourced from dams fed HyD . A maternal vitamin D by nutrient level interaction was observed for ADFI during grower/finisher phases (P = 0.05) and overall (P = 0.07) because progeny from gilts fed a low nutrient level had greater intake than cohorts from gilts fed an adequate nutrient diet, while ADFI was similar for all offspring from gilts fed HyD diets. These results indicate that manipulating nutrients during gilt development, or feeding HyD rather than StD to reproducing sows, can affect growth of their progeny to slaughter.

Ash Deposition Triggers Phytoplankton Blooms at Nishinoshima Volcano, Japan

AbstractVolcanoes that deposit eruptive products into the ocean can trigger phytoplankton blooms near the deposition area. Phytoplankton blooms impact the global carbon cycle, but the specific conditions and mechanisms that facilitate volcanically triggered blooms are not well understood, especially in low nutrient ocean regions. We use satellite remote sensing to analyze the chlorophyll response to an 8‐month period of explosive and effusive activity from Nishinoshima volcano, Japan. Nishinoshima is an ocean island volcano in a low nutrient low chlorophyll region of the Northern Pacific Ocean. From June to August 2020, during explosive activity, satellite‐derived chlorophyll‐a was detectable with amplitudes significantly above the long‐term climatological value. After the explosive activity ceased in mid‐August 2020, these areas of heightened chlorophyll concentration decreased as well. In addition, we used aerial observations and satellite imagery to demonstrate a spatial correlation between blooms and ash plume direction. Using a sun‐induced chlorophyll‐a fluorescence satellite product, we confirmed that the observed chlorophyll blooms are phytoplankton blooms. Based on an understanding of the nutrients needed to supply blooms, we hypothesize that blooms of nitrogen‐fixing phytoplankton led to a 1010–1012 g drawdown of carbon. Thus, the bloom could have significantly mediated the output of carbon from the explosive phase of the eruption but is a small fraction of anthropogenic CO2 stored in the ocean or the global biological pump. Overall, we provide a case study of fertilization of a nutrient‐poor ocean with volcanic ash and demonstrate a scenario where multi‐month scale deposition triggers continuous phytoplankton blooms across 1,000s of km2.