Search Results (1,752)

Roots play essential roles in the acquisition of water and minerals from soils in higher plants. However, water or nutrient limitation can alter plant root morphology. To clarify the spatial distribution characteristics of essential nutrients in citrus roots and the influence mechanism of micronutrient deficiency on citrus root morphology and architecture, especially the effects on lateral root (LR) growth and development, two commonly used citrus rootstocks, trifoliate orange (Poncirus trifoliata L. Raf., Ptr) and red tangerine (Citrus reticulata Blanco, Cre), were employed here. The analysis of the mineral nutrient distribution characteristics in different root parts showed that, except for the P concentrations in Ptr, the last two LR levels (second and third LRs) had the highest macronutrient concentrations. All micronutrient concentrations in the second and third LRs of Ptr were higher than those of Cre, except for the Zn concentration in the second LR, which indicates that Ptr requires more micronutrients to maintain normal root system growth and development. Principal component analysis (PCA) showed that B and P were very close in terms of spatial distribution and that Mo, Mn, Cu, and Fe contributed significantly to PC1, while B, Cu, Mo, and Zn contributed significantly to PC2 in both rootstocks. These results suggest that micronutrients are major factors in citrus root growth and development. The analysis of root morphology under micronutrient deficiency showed that root growth was more significantly inhibited in Ptr and Cre under Fe deficiency (FeD) than under other micronutrient deficiencies, while Cre roots exhibited better performance than Ptr roots. From the perspective of micronutrient deficiency, FeD and B deficiency (BD) inhibited all root morphological traits in Ptr and Cre except the average root diameter, while Mn deficiency (MnD) and Zn deficiency (ZnD) had lesser impacts, as well as the morphology of the stem. The mineral nutrient concentrations in Ptr and Cre seedlings under micronutrient deficiency revealed that single micronutrient deficiencies affected both their own concentrations and the concentrations of other mineral nutrients, whether in the roots or in stems and leaves. Dynamic analysis of LR development revealed that there were no significant decreases in either the first or second LR number in Ptr seedlings under BD and ZnD stress. Moreover, the growth rates of first and second LRs in Ptr and Cre did not significantly decrease compared with the control under short-term (10 days) BD stress. Altogether, these results indicate that micronutrients play essential roles in citrus root growth and development. Moreover, citrus alters its root morphology and biological traits as a nutrient acquisition strategy to maintain maximal micronutrient acquisition and growth. The present work on the spatial distribution characteristics and micronutrient deficiency of citrus roots provides a theoretical basis for effective micronutrient fertilization and the diagnosis of micronutrient deficiency in citrus. Full article

Freshwater reservoirs serve as vital water sources for numerous residential areas. However, the excessive presence of nutrients, such as nitrogen and phosphorus, stimulates rapid algal proliferation, leading to the occurrence of algal blooms. To prevent this phenomenon, it is imperative to conduct regular ecological surveys aimed at assessing water quality and monitoring the dynamic composition of aquatic biological communities within the reservoir’s ecosystem. In this study, seasonal changes in water quality parameters and the spatial and temporal distribution of planktonic algae at 14 sampling sites in the Danjiangkou reservoir were analyzed. A total of 136 taxonomic units of planktonic algae were identified, belonging to 8 phyla, 41 families, and 88 genera, with the dominant algae belonging to the phyla Chlorophyta, Bacillariophyta, and Cyanophyta. The order of abundance of the algae was summer > autumn > spring > winter and Hanku > Intake > Danku > Outflow. WT, pH, DO, COD_Mn, and Chl a were the primary drivers influencing the changes in the planktonic algal community within the reservoir. Two dominant algae, Chlamydomonas debaryana and Scenedesmus quadricauda, were isolated and cultured indoors to simulate the growth behaviors of algae in the Danjiangkou reservoir. The results show that the growth of C. debaryana was severely limited by the temperature, light, and nutrient concentration, whereas the growth of S. quadricauda was slightly affected under different temperature and light conditions and could occur at low concentrations of nitrogen and phosphorus nutrients. With excess nutrient levels, excessive proliferation of S. quadricauda could potentially cause algal blooms. This study examined the growth characteristics of the dominant algae in the Danjiangkou reservoir under laboratory conditions and delved into their interdependencies with environmental factors, aiming to furnish a theoretical and experimental foundation for investigating algal community dynamics and preventing algal blooms within the freshwater reservoir. Full article

The increasing need for sustainable waste management and abundant availability of banana tree waste, a byproduct of widespread banana cultivation, have driven interest in biomass conversion through clean fuels. This study investigates the oxidative pyrolysis of banana tree waste to optimize process parameters and enhance bio-oil production. Experiments were conducted using a fluidized bed reactor at temperatures ranging from 450 °C to 550 °C, with oxygen to biomass (O/B) ratios varying from 0.05 to 0.30. The process efficiently converts this low-cost, renewable biomass into valuable products and aims to reduce energy intake during pyrolysis while maximizing the yield of useful products. The optimal conditions were identified at an O/B ratio of 0.1 and a temperature of 500 °C, resulting in a product distribution of 26.4 wt% for bio-oil, 20.5 wt% for bio-char, and remaining pyro-gas. The bio-oil was rich in oxygenated compounds, while the bio-char demonstrated a high surface area and nutrient content, making it suitable for various applications. The pyro-gas primarily consisted of carbon monoxide and carbon dioxide, with moderate amounts of hydrogen and methane. This study supports the benefits of oxidative pyrolysis for waste utilization through a self-heat generation approach by partial feed combustion providing the internal heat required for the process initiation that can be aligned with the principles of a circular economy to achieve environmental responsibility. Full article

Various nutrients are needed during the sugarcane growing season for plant development and productivity. However, traditional methods for assessing nutritional status are often costly and time consuming. This study aimed to determine the level of nitrogen (N), phosphorus (P), potassium (K) and chlorophyll of sugarcane plants using remote sensing. Remotely sensed images were obtained using a MicaSense RedEdge-P camera attached to a drone. Leaf chlorophyll content was measured in the field using an N-Tester chlorophyll meter, and leaf samples were collected and analyzed in the laboratory for N, P and K. The highest correlation between field samples and predictor variables (spectral bands, selected vegetation indices, and plant height from Light Detection and Ranging (LiDAR)), were noted.The spatial distribution of chlorophyll, N, P, and K maps achieved 60%, 75%, 96% and 50% accuracies, respectively. The spectral profiles helped to identify areas with visual differences. Spatial variability of nutrient maps confirmed that moisture presence leads to nitrogen and potassium deficiencies, excess phosphorus, and a reduction in vegetation density (93.82%) and height (2.09 m), compared to green, healthy vegetation (97.64% density and 3.11 m in height). This robust method of assessing foliar nutrients is repeatable for the same sugarcane variety at certain conditions and leads to sustainable agricultural practices in Costa Rica. Full article

This study determined the interaction between soybean hulls (SHs) and enzymes (β-mannanase) to improve the sustainability and efficacy of feeding programs for laying hens during peak production while ensuring the best health and efficiency. In a completely randomized design (CRD), 200 golden-brown hens were fed for four weeks (33 to 36 weeks) and randomly distributed into four groups, each containing four replicates of ten birds, with one group receiving a control diet (P0) and the others receiving diets that contained four combinations of SHs and enzymes (ENZs). e.g., 3% SHs and 0.02 g/kg ENZs (P1), 3% SHs and 0.03 g/kg ENZs (P2), 9% SHs and 0.02 g/kg ENZs (P3), and 9% SHs and 0.03 g/kg ENZs (P4). Although most egg quality measures remained similar, the P2 group showed enhanced (p = 0.630) egg weight, albumen weight, and height. Moreover, the P2 group improved gut (p < 0.05) shape by increasing villus width, height, crypt depth, and surface area throughout intestinal sections, while the P4 group markedly improved total cholesterol and LDL (p = 0.022) levels. The P1, P2, and P4 groups exhibited a significant enhancement in dry matter (p = 0.022) and crude fiber (p = 0.046) digestibility, while the P2 group demonstrated superior crude protein digestibility (p = 0.032), and the P1 and P2 groups showed increased crude fat digestibility compared to the other groups. In conclusion, adding 3% of SHs and 30 mg/kg of ENZs (β-mannanase) to the feed may help laying hens, enhance gut health and some egg quality indices, and decrease blood cholesterol and LDL levels without compromising nutrient digestibility. Full article

[Objective] This study focused on the primary tea-producing regions of Shangluo City (ranging from 108°34′20″ E to 111°1′25″ E and 33°2′30″ N to 34°24′40″ N), which include Shangnan County, Zhen’an County, Zhashui County, Danfeng County, and Shanyang County. The aim was to explore the characteristics and influencing factors of soil nutrient content variation across different tea gardens in the area. The study involved an analysis of various soil nutrient indicators and an investigation of their correlations to assess the nutrient status of tea gardens in Shangluo City. [Method] A total of 228 soil samples from these tea gardens were quantitatively analyzed for pH, soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), available potassium (AK), as well as clay, silt, and sand content. Additionally, the soil texture was qualitatively analyzed. Statistical methods including analysis of variance (ANOVA), correlation analysis, principal component analysis (PCA), and regression analysis were performed using SPSS software to examine the relationships between soil nutrients and texture in relation to altitude, latitude, and fertility status. [Results] The results indicated that the pH of tea garden soils in Shangluo City was relatively stable, ranging from 4.3 to 7.6, with the mean of 5.9 and a coefficient of variation of 11.0%. The soil organic matter (SOM) content varied from 7.491 to 81.783 g/kg, exhibiting a moderate variability with a coefficient of variation of 38.75%. The mean values for total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), available phosphorus (AP), total potassium (TK), available potassium (AK), clay, silt, and sand were 1.53 g/kg, 213 mg/kg, 0.85 g/kg, 49.1 mg/kg, 5.5 g/kg, 110 mg/kg, 3.99, 44.89, and 51.11, respectively. AN and AP displayed higher coefficients of variation at 57% and 120.1%, respectively. Significant differences in pH, SOM, TN, TP, TK, silt, and sand were observed at varying elevations, while TN, TP, TK, clay, silt, and sand varied significantly across different latitudes. Principal component analysis (PCA) results revealed that altitude had four principal components with eigenvalues greater than 1, accounting for 71.366% of the total variance, whereas latitude exhibited five principal components with eigenvalues exceeding 1, explaining 76.304% of the total variance. Regression analysis indicated that altitude exerted a stronger influence on soil indicators, as demonstrated by a well-fitting model (Model 4), where the coefficients of principal components 1, 3, and 4 were positive, while that of principal component 2 was negative. In contrast, latitude influenced soil indicators most effectively in Model 3, where the coefficient of principal component 5 was positive, and the coefficients of principal components 1 and 4 were negative. [Conclusions] The variation in soil nutrients and pH in the tea gardens of Shangluo City is closely associated with altitude and latitude. Notably, there is no discernible trend of pH acidification. Therefore, tea garden management should prioritize the rational application of soil nutrients at varying altitudes and focus on enhancing soil texture at different latitudes to adapt to the diverse soil characteristics under these conditions, thereby promoting sustainable development in tea gardens. Full article

In June 2023, following the breach of the Nova Kakhovka Dam during the Ukraine-Russia war, a comprehensive study was conducted along the Romanian Black Sea coast to assess water quality and mesozooplankton communities. Surface water analyses revealed significant gradients in nutrient levels and salinity, particularly from north to south, influenced by the influx of freshwater and nutrients from riverine sources and the dam breach. Flooding was found to significantly impact nutrient dynamics and species distributions, with increased concentrations of SiO₄ and NO₃ in flooded stations. A strong relationship was observed between environmental factors and biological assemblages, with silicates identified as a key driver. Biodiversity patterns varied across regions, with the Shannon–Wiener Index indicating lower zooplankton diversity in transitional waters, reflecting environmental stress. Statistical methods, including correlation analysis, multidimensional scaling, t-tests, and canonical analysis, were employed to investigate the links between mesozooplankton communities and environmental variables. These findings underscore disruptions in trophic dynamics and ecosystem balance, emphasizing the need for integrated environmental management strategies to mitigate further degradation and foster the ecological recovery of the Black Sea. Full article

Fusarium mycotoxins often co-occur in broiler feed, and their presence negatively impacts health even at subclinical concentrations, so there is a need to identify the concentrations of these toxins that do not adversely affect chickens health and performance. The study was conducted to evaluate the least toxic effects of combined mycotoxins fumonisins (FUM), deoxynivalenol (DON), and zearalenone (ZEA) on the production performance, immune response, intestinal morphology, and nutrient digestibility of broiler chickens. A total of 960 one-day-old broilers were distributed into eight dietary treatments: T1 (Control); T2: 33.0 FUM + 3.0 DON + 0.8 ZEA; T3: 14.0 FUM + 3.5 DON + 0.7 ZEA; T4: 26.0 FUM + 1.0 DON + 0.2 ZEA; T5: 7.7 FUM + 0.4 DON + 0.1 ZEA; T6: 3.6 FUM + 2.5 DON + 0.9 ZEA; T7: 0.8 FUM + 1.0 DON + 0.3 ZEA; T8: 1.0 FUM + 0.5 DON + 0.1 ZEA, all in mg/kg diet. The results showed that exposure to higher mycotoxin concentrations, T2 and T3, had significantly reduced body weight gain (BWG) by 17% on d35 (p < 0.05). The T2, T3, and T4 groups had a significant decrease in villi length in the jejunum and ileum (p < 0.05) and disruption of tight junction proteins, occludin, and claudin-4 (p < 0.05). Higher mycotoxin groups T2 to T6 had a reduction in the digestibility of amino acids methionine (p < 0.05), aspartate (p < 0.05), and serine (p < 0.05); a reduction in CD4+, CD8+ T-cell populations (p < 0.05) and an increase in T regulatory cell percentages in the spleen (p < 0.05); a decrease in splenic macrophage nitric oxide production and total IgA production (p < 0.05); and upregulated cytochrome P450-1A1 and 1A4 gene expression (p < 0.05). Birds fed the lower mycotoxin concentration groups, T7 and T8, did not have a significant effect on performance, intestinal health, and immune responses, suggesting that these concentrations pose the least negative effects in broiler chickens. These findings are essential for developing acceptable thresholds for combined mycotoxin exposure and efficient feed management strategies to improve broiler performance. Full article

Soil moisture content is a key factor influencing plant growth and agricultural productivity, directly impacting water uptake, nutrient absorption, and stress resistance. This study proposes a rapid, low-cost, non-destructive method for dynamically monitoring soil moisture at depths of 0–200 cm throughout the crop growth period under dryland conditions, with validation in soybean cultivation. During critical soybean growth stages, UAV multispectral data of the canopy were collected, and ground measurements were conducted for three GPS-referenced 50 cm × 50 cm plots to obtain canopy leaf water content, coverage, and soil volumetric moisture at 20 cm intervals. Ten vegetation indices were constructed from multispectral data to explore statistical relationships between vegetation indices, surface soil moisture, canopy leaf water content, and deeper soil moisture. Predictive models were developed and evaluated. Results showed that the NDVI-based nonlinear regression model achieved the best performance for leaf water content (R² = 0.725), and a significant correlation was found between canopy leaf water content and 0–20 cm soil moisture (R² = 0.705), enabling predictions of deeper soil moisture. Surface soil models accurately estimated 0–200 cm soil moisture distribution (R² = 0.9995). Daily water dynamics simulations provided robust support for precision irrigation management. This study demonstrates that UAV multispectral remote sensing combined with ground sampling is a valuable tool for soybean water management, supporting precision agriculture and sustainable water resource utilization. Full article

The mechanisms by which the soil physical structure, nutrient conditions, understory vegetation diversity and forest meteorological factors influence fine root (<2 mm diameter) characteristics mediated by soil moisture content (SMC) and soil heat flux (SHF) remain uncertain under climate change. Therefore, in this research, continuous observations were made of the fine root growth, death and turnover of cypress plantations, as well as the SMC and SHF under the management of four thinning intensities in hilly areas in central Sichuan from 2021 to 2023. The fine root data were obtained using the microroot canals (minirhizotron) in the study, and the soil hydrothermal data were obtained using the ECH2O soil parameter sensor and the PC-2R SHF data logger. In the time series, the fine root growth, death and turnover of the cypress plantations with different thinning intensities first increased and then decreased throughout the year; the vertical center of the gravity of the fine roots of cypress was concentrated in the 30–50 cm range. This research also revealed that the variability in the SMC decreased with increasing soil depth. Additionally, the SHF was transmitted from greater soil depths to the surface in unthinned cypress plantation at a rate of 0.036 per year, which decreased the heat in the fine root region. However, SHF was transmitted from the soil surface to greater depths at rates of 0.012 per year, 0.08 per year and 0.002 per year, which increased the heat in the fine root area. The redundancy analysis (RDA) and structural equation model (SEM) results indicated that the SMC and soil heat energy distribution pattern obviously affected fine root growth, death and turnover in the cypress plantation. However, the climate conditions in the forest, the characteristics of vegetation in the understory and the physical and chemical characteristics of the soil directly or indirectly affect the characteristics of the fine roots of cypress plantations with changes in thinning intensity. This research provides a basis for understanding ecosystem structure, nutrient cycling and carbon balance and may guide artificial plantation development and management. Full article

Soil structure, a critical indicator of soil quality, significantly influences agricultural productivity by impacting on the soil’s capacity to retain and deliver water, nutrients, and salts. Quantitative study of soil structure has always been a challenge because it involves complex spatial-temporal variability. This study employs multifractal analysis to assess the temporal variation in soil pore distribution, a pivotal factor in soil structure. Field observation data were collected in a sandy loam area of the People’s Victory Canal Irrigation scheme in Henan Province, China. A 200 m × 200 m test plot with five sampling points was used to collect soil samples at three depth layers (10–30 cm, 30–50 cm, and 50–70 cm) for soil water retention curve and particle size composition analysis, with a total of seven sampling events throughout the growing season. The results revealed that while soil particle-size distribution (Particle-SD) showed minor temporal changes, soil pore-size distribution (Pore-SD) experienced significant temporal fluctuations over a cropping season, both following a generalized power law, indicative of multifractal traits. Multifractal parameters of Pore-SD were significantly correlated with soil bulk density, with the strongest correlation in the topsoil layer (10–30 cm). The dynamic changes in soil pore structure suggest potential variations during saturation–unsaturation cycles, which could be crucial for soil water movement simulations using the Richards equation. The study concludes that incorporating time-varying parameters in simulating soil water transport can enhance the accuracy of predictions. Full article

This study investigated the elemental composition of Boerhavia elegans, addressing the gap in comprehensive trace element profiling of this medicinal plant. The research aimed to determine the distribution of macronutrients, micronutrients, and beneficial and potentially toxic elements across different plant parts (seeds, leaves, stems, and roots). Using ICP-OES analysis, two digestion methods were employed to capture both complex and labile elements. The study revealed distinct elemental distribution patterns, with iron and nickel concentrating in stems, manganese and zinc in leaves, and copper in roots. Magnesium emerged as the most abundant macronutrient, particularly in leaves. Importantly, all detected toxic elements (arsenic, chromium, lead, and cadmium) were below WHO safety limits. These findings provide crucial insights into the nutritional and safety profile of B. elegans, potentially informing its use in traditional medicine and highlighting its potential as a source of essential elements. Full article

Morel mushrooms (Morchella spp.), a globally distributed edible and medicinal fungus, possess significant economic and nutritional values. This study investigated rhizosphere soil samples collected from wild Morchella esculenta in three regions of Jilin Province. Metagenome sequencing technology was employed to analyze the structure and function of the rhizosphere microbial communities. The results indicated significant differences in microbial community composition among the samples, with the bacterial community being dominant, followed by the archaeal community. Pseudomonadota and Nitrospirae emerged as the dominant phyla, while Bradyrhizobium and Nitrospira were the co-dominant genera. A correlation analysis of environmental factors revealed that the genera Luteibacter, Streptomyces, Micromonospora, Nocardia, Actinomadura, and Paenibacillus were positively correlated with soil total nitrogen, total phosphorus, and organic matter content. In contrast, Candidatus Nitrosocosmicus showed a significant positive correlation with rapidly available nutrients. The functional annotation analysis of soil microorganisms, based on the KEGG database, revealed that within level A (highest tier), metabolic activities were the most prominent. In contrast, at level B (secondary tier), global and overview maps, carbohydrate metabolism, and amino acid metabolism were dominant. Among the top 10 pathway-level annotations, metabolic pathways, the biosynthesis of secondary metabolites, and microbial metabolism in diverse environments were significant. Environmental factors and KEGG gene network maps indicated that the available potassium, available phosphorus, and pH were closely related to level A genes, which exhibited a higher abundance of metabolism genes. This study was dedicated to deepening the understanding of the structure and function of the rhizosphere microbial community of Morchella esculenta, and providing new perspectives and insights for habitat investigations, the development of biomimetic cultivation techniques, and the domestication of wild strains to Morchella esculenta in Jilin Province. Full article

A biomonitoring study of air pollution was developed in an urban-industrial area (Seixal, Portugal) using leaves of strawberry plants (Fragaria × ananassa Duchesne ex Rozier) as biomonitors to identify the main sources and hotspots of air pollution in the study area. The distribution of exposed strawberry plants in the area was based on a citizen science approach, where residents were invited to have the plants exposed outside their homes. Samples were collected from a total of 49 different locations, and their chemical composition was analyzed for 22 chemical elements using X-ray Fluorescence spectrometry. Source apportionment tools, such as enrichment factors and principal component analysis (PCA), were used to identify three different sources, one geogenic and two anthropogenic (steel industry and traffic), besides plant major nutrients. The spatial distribution of elemental concentrations allowed the identification of the main pollution hotspots in the study area. The reliability of using strawberry leaves as biomonitors of air pollution was evaluated by comparing them with the performance of transplanted lichens by regression analysis, and a significant relation was found for Fe, Pb, Ti, and Zn, although with a different accumulation degree for the two biomonitors. Furthermore, by applying PCA to the lichen results, the same pollution sources were identified. Full article

Fungi, which are widely distributed across the Earth, have successfully managed to colonize cold environments (e.g., polar regions, alpine ecosystems, and glaciers) despite the challenging conditions for life. They are capable of living in extremely harsh environments due to their ecological versatility and morphological plasticity. It is also believed that lower eukaryotes are the most adapted to life at low temperatures among microorganisms that thrive in cold environments. They play important ecological roles, contributing to nutrient recycling and organic matter mineralization. These highly specialized microorganisms have developed adaptation strategies to overcome the direct and indirect harmful influences of low temperatures. They have evolved a wide range of complex and cooperative adaptations at various cellular levels, including modifications to the cell envelope and enzymes, the production of cryoprotectants and chaperones, and the development of new metabolic functions. Adaptation to cold environments has made fungi an exciting source for the discovery of new cold-adapted enzymes (e.g., proteinases, lipases) and secondary metabolites (e.g., pigments, osmolytes, polyunsaturated fatty acids) for widespread use in biotechnology, food technology, agriculture, pharmaceutics, molecular biology, textile industry, and environmental bioremediation in cold climates. This review aims to provide a comprehensive overview of the adaptive strategies employed by psychrophilic yeasts and fungi, highlighting their ecological roles and biotechnological potential. Understanding these adaptive mechanisms not only sheds light on microbial life in extreme environments but also paves the way for innovative applications in the food industry and agriculture. Full article