Soil Plant Research Articles

Different shifts in growth-defense tradeoff for above- and belowground of Miscanthus floridulus enhance tolerance to cadmium

The growth-defense tradeoff is a central mechanism for plants to cope with environmental challenges. Soil contamination with heavy metals, especially cadmium (Cd), can strongly influence the adaptive capacity of plants by modulating both growth and defense. However, how the growth-defense tradeoff adaptive to Cd stress and its dynamic patterns are not yet known. To elucidate these patterns, we conducted an experiment with the pioneer plant Miscanthus floridulus by subjecting it to a gradient of exogenous Cd concentrations, and calculated root mean square deviation based on 12 traits to decipher the direction and intensity of the growth-defense tradeoff. We observed that growth traits such as photosynthetic rate, chlorophyll content, above- and belowground biomass, root surface area and root diameter decreased under Cd stress, while the antioxidative compounds increased. Notably, both above- and belowground parts showed a preference for growth in the absence of Cd stress (tradeoff intensity= 0.013 and 0.013, respectively, unitless). However, under the high Cd stress (40 mg/kg), the aboveground tradeoff remained towards growth (tradeoff intensity= 0.024), while the belowground tradeoff shifted towards defense (tradeoff intensity= −0.046). Under 10 and 20 mg/kg Cd stress, the shifts were uncertain towards either growth or defense for above and belowground parts, suggesting a complex above-belowground interplay. The belowground tradeoff was mainly influenced by plant Cd accumulation, soil fluorescein diacetate hydrolase (S.FDA), and soil available potassium. In contrast, the aboveground tradeoff was primarily driven by plant hydrogen peroxide (H₂O₂) accumulation, S.FDA, and soil alkaline phosphomonoesterase. Overall, Cd in soil altered physicochemical properties and Cd accumulation, which in turn had a significant impact on belowground defense mechanisms. We revealed that the shifts in growth-defense tradeoff differed between aboveground and belowground under Cd stress. Our results provided a new insight into the physiological and biochemical mechanisms underlying plant adaptation to Cd stress from the perspective of the growth-defense tradeoff.

Effects of long-term nighttime warming on extractable soil element composition in a Mediterranean shrubland

Understanding the soil biogeochemical responses to increasing global warming in the near future is essential for improving our capacity to mitigate the impacts of climate change on highly vulnerable Mediterranean ecosystems. Previous studies have primarily focused on the effects of warming on various biogeochemical processes. However, there is limited knowledge about how the changes in water availability associated to high temperatures can alter the bioavailability and dynamics of soil elements, thereby impacting ecosystem productivity, species composition, and pollution through soil biogeochemical and hydrological processes. In this study, we investigated the effects of long-term nighttime warming on the extractable concentrations of organic carbon (EOC), total nitrogen (ETN), total phosphorus (ETP), and 17 mineral elements (arsenic (As), calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), potassium (K), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), sulfur (S), strontium (Sr), vanadium (V), and zinc (Zn)) through environmental experiments in a semi-arid Mediterranean shrubland. We explored the potential biotic and abiotic mechanisms underlying the seasonal and long-term changes in extractable-mobilizable elemental composition and concentrations. Our findings revealed that prolonged warming led to higher mean annual soil temperature (with an average increase of 0.67 °C from 1999 to 2014), accumulation of soil organic matter (EOC) and extractable concentrations of soil elements (particularly increased ETP and extractable Ca, Mg, Cu, Sr, Mn, and As). These changes were attributed to uniformly higher activities of extracellular soil enzymes and/or lower plant photosynthetic and nutrient uptake capacity linked to more water deficit under warmer conditions. Seasonality unevenly altered element extractable concentrations, with soil microclimate (temperature and water content) and biological (soil microbial and plant) activity being the main drivers of this variability, thus influencing soil element composition. These results suggest significant fluctuations in the extractable concentrations of specific mineral elements in these soils, implying potential future variations in soil element composition as well as the loss of total element concentrations/contents in semi-arid Mediterranean ecosystems due to increasing warming. Therefore, these findings enhance our ability to predict ecosystem management strategies and mitigate the observed negative impacts on plant-soil systems and water quality in the context of climate change.

Phytoremediation of Pb-polluted soil using bermudagrass: Effect of mowing frequencies

Plant lead (Pb) tolerance and accumulation are key characteristics affecting phytoremediation efficiency. Bermudagrass is an excellent candidate for the remediation of Pb-polluted soil, and it needs to be mowed regularly. Here, we explored the effect of different mowing frequencies on the remediation of Pb-contaminated soil using bermudagrass. Mowing was found to decrease the biomass and photosynthetic efficiency of bermudagrass under Pb stress, thereby inhibiting its growth. Although mowing exacerbated membrane peroxidation, successive mowing treatments alleviated peroxidation damage by regulating enzymatic and nonenzymatic systems. A comprehensive evaluation of Pb tolerance revealed that all the mowing treatments reduced the Pb tolerance of bermudagrass, and a once-per-month mowing frequency had a less negative effect on Pb tolerance than did more frequent mowing. In terms of Pb enrichment, mowing significantly increased the Pb concentration, total Pb accumulation, translocation factor (TF), and bioenrichment factor (BCF) of bermudagrass. The total Pb accumulation was greatest under the once-a-month treatment, while the TF and BCF values were greatest under the three-times-a-month mowing treatment. Additionally, the decrease in soil pH and DOC were significantly correlated with the soil available Pb content and plant Pb accumulation parameters. The results showed that changes in the rhizosphere are crucial factors regulating Pb uptake in bermudagrass during mowing. Overall, once-a-month mowing minimally affects Pb tolerance and maximizes Pb accumulation, making it the optimal mowing frequency for soil Pb remediation by bermudagrass. This study provides a novel approach for the remediation of Pb-contaminated soil with bermudagrass based on mowing.

Grazing period management affects the accumulation of plant functional groups, and soil nutrient pools and regulates stoichiometry in the desert steppe of Northwest China

To understand how nutrient cycling and sequestration are influenced by different grazing periods, the C:N:P stoichiometry features of the plant–soil interface in the desert steppe were measured and evaluated. The 5-year seasonal grazing experiment employed four grazing period treatments: traditional time of grazing (TG), early termination of grazing (EG), delayed start of grazing (DG), and delayed start and early termination of grazing (DEG). Additionally, fenced off desert steppe served as the control. The grazing periods each had a differing impact on the C:N:P stoichiometry in both plant functional group and soil depth comparisons. Compared to the EG, DG, and DEG treatments, the TG treatment had a more significant impact on the C, N, and P pools of grass, as well as the C:P and N:P ratios of forbs, but had a reduced effect on the C:P and N:P ratios of legumes. In contrast to plants, the DG treatment exhibited greater advantages in increasing C pools within the 0–40 cm soil layer. Furthermore, in the 10–20 cm soil layer, the C:P and N:P ratios under the EG treatment were significantly higher, ranging from 8.88% to 53.41% and 72.34%–121.79%, respectively, compared to the other treatments (TG, DG, and DGE). The primary drivers of the C, N, and P pools during different grazing periods were above-ground biomass (AGB) and litter biomass (LB). Both lowering the plant C:P and N:P ratios and considerably raising the plant P pool during different grazing periods greatly weakened the P limitation of the desert steppe environment. It is predicted that delayed start grazing might be a management strategy for long-term ecosystem sustainability, as it regulates above-ground nutrient allocation and has a positive effect on soil C and N pools.

Facile synthesis, release mechanism, and life cycle assessment of amine-modified lignin for bifunctional slow-release fertilizer

Biomass-based slow-release fertilizers (SRFs) are a sustainable solution for addressing food scarcity, improving fertilizer efficiency, and reducing pollution, whereas they still face complex preparation, high costs, and low release characteristics. This study introduces a simple and innovative approach to producing bifunctional green SRFs with controlled release and conditioning properties for saline soils and harsh environments. The method involves a one-pot preparation of microsphere-structured amine-modified lignin slow-release fertilizer (L-UX) using biomass lignin as the starting material. The L-UX demonstrates an exceptional fertilizer loading rate (66.2 %) and extended slow-release performance (288 h), effectively enhancing the fertilizer's release ability. Compared to traditional fertilizers, the bifunctional L-UX significantly improves soil water retention capacity (824.3 %), plant growth, and germination percentage in challenging soil conditions (133 %). These findings highlight the potential of L-UX as a large-scale controlled-release fertilizer in harsh environments. A life cycle assessment (LCA) was also conducted to evaluate the environmental impact of L-UX from its production to disposal. This revealed that L-UX has a minimal environmental footprint compared to conventional inorganic fertilizers. This study further supports the widespread application of L-UX as an environmentally friendly alternative.

Appropriate sulfur fertilization in contaminated soil enhanced the cadmium uptake by hyperaccumulator Sedum alfredii Hance

The biogeochemical processes of sulfur and heavy metals in the environment are closely related to each other. We investigated the influence of sulfur addition on hyperaccumulator Sedum alfredii Hance growth, cadmium (Cd) accumulation, soil Cd bioavailability, soil bacterial communities and plant transcriptome responses. The results showed that an appropriate rate of sulfur addition (1.0 or 2.5 g/kg) enhanced the growth of Sedum alfredii Hance plants as well as their accumulation of Cd. A high rate of sulfur addition (5.0 or 10.0 g/kg) causes toxicity to Sedum alfredii Hance plants. The application of an appropriate amount of sulfur to the soil increased the abundance of sulfur-oxidizing bacteria such as Sulfuriferula and Thiobacillus; acid-fast bacillus such as Alicyclobacillus; and cadmium-tolerant bacteria such as Bacillus and Rhodanobacter. This led to a decrease in pH and an increase in bioavailable Cd in the soil. RNA sequencing revealed that the addition of sulfur to soils led to the up regulation of most of the differentially expressed genes (DEGs) involved in “photosynthesis” and “photosynthesis, light reaction” in Sedum alfredii Hance leaves. Moreover, the “plant hormone signal transduction” pathway was significantly enriched with sulfur addition. Sulfur assimilation in Sedum alfredii Hance plants may promote photosynthesis and hormone synthesis, leading to Cd tolerance in these plants. Our study revealed that sulfur fertilization enhanced the efficiency of Cd phytoremediation in Sedum alfredii Hance plants.

Research of the impact of environmentally persistent free radicals on chemical element behaviour in the soil–plant system

Environmentally persistent free radicals (EPFRs) may pose a potential risk to the ecosystem and human health via oxidation stress and are considered emerging contaminants. Being stable with a lifetime of minutes or several months and abundant in transitional matrices (e.g. biochar), EPFRs continue to affect deposits (e.g. soil) and related media (plants) when the transitional matrices (e.g. biochar) are applied. The impact of EPFR on the plant uptake of chemical elements (CEs) was studied in the field conditions where, for two years, biochar and fertilisers were applied to the agricultural soil for winter triticale cultivation. EPFRs determination methods, along with the element uptake indices (bioaccumulation and biophilicity) and the method of the dynamic factors were applied. Results have shown that EPFRs have influenced the soil properties relevant to CE soil bioavailability and bioaccumulation in plants. The impact of EPFRs on CE transport in the soil–plant system was observed to influence the biogeochemical behaviour of CEs in the soil–plant system. This work provides the first findings on EPFRs-induces changes on CE bioavailability and bioaccumulation intensity, indicating the higher plant uptake risk of some potentially toxic elements (such as Cr).

Microbial C and N Metabolism Alterations Based on Soil Metagenome and Different Shrub Invasion Stages in Sanjiang Plain Wetlands.

Shrub invasion affects plant growth and soil physicochemical properties, resulting in soil microbiota metabolic pathway changes. However, little is known about the shrub expansion intensity of microbial metabolic pathway processes. In this study, we used metagenome sequencing technology to investigate changes in soil microbial C and N metabolic pathways and community structures, along with different shrub invasion intensities, in the Sanjiang Plain wetlands. Different shrub invasion intensities significantly affected the soil microbial composition (β diversity), with no significant effect on the α diversity compared to CK. AN, pH, and TP were the major factors influencing the microbial community's structures. Compared to CK, the shrub expansion intensity did not significantly affect C fixation and central metabolism but significantly reduced methanogenesis, which involves the CO2-to-methane transition that occurs in methane metabolism, and denitrification, the nitrite to nitric oxide (nirK or nirS) transition that occurs in N metabolism. This study provides an in-depth understanding of the biogeochemical cycles of wetland ecosystems in cold northern regions undergoing shrub invasion.

Impact of rice-husk biochar on soil attributes, microbiome interaction and functional traits of radish plants: A smart candidate for soil engineering

This study is based on the application of different doses of rice husk biochar; RHB (1, 5, 10, 15, and 20 t/ha) in wastewater-irrigated soil to observe its impact on the soil qualities and functional attributes of the radish plants. The results showed that the RHB treatments increased the soil pH, electrical conductivity (EC), bulk density (BD), soil organic carbon (SOC), total nitrogen (TN), available phosphorous (AP), enzymatic activities, and microbial biomass in the soil. The soil metagenome analysis at 15 t/ha showed more abundance of microbial communities like Actinobacteria, Acidobacteria, and Nitrospira over to control soil. On the other hand, more significantly it led to a reduction in the availability of Cd, Cr, Ni, Zn, and Cu by 73, 60, 63, 61, and 68 %, respectively maximally at 20 t/ha dose of biochar application. Along with that it also led to the level of the all the toxic heavy metals below their safe limit in the edible part of the radish plants. All the doses of RHB application have resulted improvements in functional attributes of the radish plants by reducing the production of oxidative biomarkers more significantly at 15 and 20 t/ha doses of biochar compared to the control plants. Among all the doses the biomass of edible parts of plant i.e., root was increased and the maximum increment was found at 15 t/ha over to control plants and later on, there was an insignificant difference. The total concentrations of Cd, Cr, Ni, Zn, and Cu were decreased in the root and shoot of the plants in a dose-dependent manner. The correlation biplot also showed that with the amendment of biochar, there was a significant correlation between the soil properties and plant yield.

Efficient utilization of winter nitrogen sources by soil microorganisms and plants in a temperate grassland

In seasonal snow-covered regions, the soil microbial community remains highly active, enabling nitrogen (N) mineralization processes to occur even during the winter. Therefore, winter N accumulation is likely to be a primary N source for plant growth in the subsequent spring. However, the availability of winter N resources (i.e., ammonium and nitrate N) to soil microorganisms and plants in temperate grasslands remains unclear. Here, we applied 15NH4Cl and K15NO3 tracers before autumn-winter freezing, and then investigated the retention of both 15N tracers in soil microorganisms and different plants during the winter and spring period in a typical steppe. The results showed that approximately 33 % and 27 % of 15NH4Cl and K15NO3 tracers were immobilized by soil microorganisms, while little had been uptake by plants during winter. In the subsequent spring, soil retained 32 % and 34 %, microorganisms immobilized 5.1 % and 5.2 %, plant acquired 40 % and 28 % of the 15NH4Cl and K15NO3 tracers, respectively. At a temporal scale, perennial bunch grasses first acquired 15N in the winter-spring transition, followed by perennial rhizome grasses and forbs in early spring, while legumes utilized little 15N. In contrast, the 15N absorption capacity of perennial rhizome grasses and perennial forbs was similar to that of bunch grasses. Additionally, only dominant bunch grasses showed a preference for ammonium N over nitrate N, while other plant species did not exhibit a clear preference for different forms of N. Our results suggest that the temporal differentiation of N utilization between plants and microorganisms enhances the availability of winter N sources. Importantly, the differences among plant species in the timing and quantity of winter N resource utilization contribute to species coexistence in temperate grasslands. This study highlights the crucial role of winter N accumulation as a primary N source for plant growth in temperate grasslands. Understanding the availability of winter N sources for plant and microbial growth is essential for predicting plant community dynamics and species coexistence in these ecosystems.

Soil water dynamics and plant water uptake: Primeval mature vs. debris flow-developed half-mature subalpine fir stands in the eastern Tibetan Plateau

Natural disaster can disrupt soil structure and replace established vegetation with younger plants, altering the local hydrological processes. We used hydrogen and oxygen stable isotopes to examine soil water dynamics and plant water uptake patterns in two adjacent fir stands in the eastern Qinghai-Tibet Plateau: a primeval mature stand (MF, finer- textured soil) and a debris flow-developed half-mature stand (HMF, coarser-textured soil). Our results showed that the isotopic composition and soil gravimetric water content (SWC) in deep soil water in MF exhibited a more pronounced hysteresis pattern in response to precipitation compared to HMF, indicating lower turnover rate of soil water in MF. This was also confirmed by a smaller contribution of preferential flow to deep soil water in MF compared to HMF. The higher water storage (higher SWC values) and lower turnover rate of soil water suggest a higher soil water buffer capacity in MF. Additionally, both stands showed no significant difference in plant water sources, but plants in MF used more winter precipitation due to the lower soil water turnover rate. These differences suggest MF may be more vulnerable to water disasters, while HMF may be more susceptible to seasonal droughts under climate change. Our insights enhance understanding of hydrological processes linked to changing surface conditions and offer valuable information for managing forest water resources in mountainous regions.

Radiation-Tolerant Fibrivirga spp. from Rhizosphere Soil: Genome Insights and Potential in Agriculture.

The rhizosphere of plants contains a wide range of microorganisms that can be cultivated and used for the benefit of agricultural practices. From garden soil near the rhizosphere region, Strain ES10-3-2-2 was isolated, and the cells were Gram-negative, aerobic, non-spore-forming rods that were 0.3-0.8 µm in diameter and 1.5-2.5 µm in length. The neighbor-joining method on 16S rDNA similarity revealed that the strain exhibited the highest sequence similarities with "Fibrivirga algicola JA-25" (99.2%) and Fibrella forsythia HMF5405T (97.3%). To further explore its biotechnological potentialities, we sequenced the complete genome of this strain employing the PacBio RSII sequencing platform. The genome of Strain ES10-3-2-2 comprises a 6,408,035 bp circular chromosome with a 52.8% GC content, including 5038 protein-coding genes and 52 RNA genes. The sequencing also identified three plasmids measuring 212,574 bp, 175,683 bp, and 81,564 bp. Intriguingly, annotations derived from the NCBI-PGAP, eggnog, and KEGG databases indicated the presence of genes affiliated with radiation-resistance pathway genes and plant-growth promotor key/biofertilization-related genes regarding Fe acquisition, K and P assimilation, CO2 fixation, and Fe solubilization, with essential roles in agroecosystems, as well as genes related to siderophore regulation. Additionally, T1SS, T6SS, and T9SS secretion systems are present in this species, like plant-associated bacteria. The inoculation of Strain ES10-3-2-2 to Arabidopsis significantly increases the fresh shoot and root biomass, thereby maintaining the plant quality compared to uninoculated controls. This work represents a link between radiation tolerance and the plant-growth mechanism of Strain ES10-3-2-2 based on in vitro experiments and bioinformatic approaches. Overall, the radiation-tolerant bacteria might enable the development of microbiological preparations that are extremely effective at increasing plant biomass and soil fertility, both of which are crucial for sustainable agriculture.

A systematic study on synergistic effect of biochar-compost in improving soil function and reducing cadmium toxicity in Spinacia oleracea L.

With its direct or indirect reliance on agriculture for a living, the Indian economy is heavily dependent on this industry. Food insecurity is a result of decreased agriculture productivity due to growing contamination and pollution. Biochar is an organic carbon bound environment friendly material known for enhancing soil functions and plant growth. On the other hand, compost is an organic, nutrient-rich product that is formed by an aerobic process and is used as an amendment. Both of these have numerous benefits as amendment in the soil-plant system. This is a complete study on the effects of applying biochar and compost separately and in combination at ratios of 0 %, 1 %, and 2 % in a cadmium contaminated soil (0 mg/kg, 4 mg/kg and 8 mg/kg Cd). Their effect was studied on the soil characteristics, seed germination, morphology, photosynthetic pigments, oxidative stress, enzymatic and non-enzymatic antioxidant activity in spinach plant grown in contaminated soil in Chhattisgarh state, India. The results depicted that combination of biochar and compost was beneficial in improving soil-plant productivity. Compost and biochar mixtures improved the soil quality and decreased Cd concentration. When comparing the biochar-compost combination to either biochar or compost alone, the plant morphological changes and chlorophyll content increased to a greater extent in their combined application. Proline content and enzymatic activities were similarly enhanced in the biochar-compost mixture. Their amendment showed effective potential in improving spinach growth and development in the polluted soil.

Impact of Intercropping Five Medicinal Plants on Soil Nutrients, Enzyme Activity, and Microbial Community Structure in Camellia oleifera Plantations.

Intercropping medicinal plants plays an important role in agroforestry that can improve the physical, chemical, and biological fertility of soil. However, the influence of intercropping medicinal plants on the Camellia oleifera soil properties and bacterial communities remains elusive. In this study, five intercropping treatment groups were set as follows: Curcuma zedoaria/C. oleifera (EZ), Curcuma longa/C. oleifera (JH), Clinacanthus nutans/C. oleifera (YDC), Fructus Galangae/C. oleifera (HDK), and Ficus simplicissima/C. oleifera (WZMT). The soil chemical properties, enzyme activities, and bacterial communities were measured and analyzed to evaluate the effects of different intercropping systems. The results indicated that, compared to the C. oleifera monoculture group, YDC and EZ showed noticeable impacts on the soil chemical properties with a significant increase in total nitrogen (TN), nitrate nitrogen (NN), available nitrogen (AN), available phosphorus (AP), and available potassium (AK). Among them, the content of TN and AK in the rhizosphere soil of Camellia oleifera in the YDC intercropping system was the highest, which was 7.82 g/kg and 21.94 mg/kg higher than CK. Similarly, in the EZ intercropping system, the content of NN and OM in the rhizosphere soil of Camellia oleifera was the highest, which was higher than that of CK at 722.33 mg/kg and 2.36 g/kg, respectively. Curcuma longa/C. oleifera (JH) and Clinacanthus nutans/C. oleifera (YDC) had the most effect on soil enzyme activities. Furthermore, YDC extensively increased the activities of hydrogen peroxide and acid phosphatase enzymes; the increase was 2.27 mg/g and 3.21 mg/g, respectively. While JH obviously increased the urease activity, the diversity of bacterial populations in the rhizosphere soil of the intercropping plants decreased, especially the Shannon index of YDC and HDK. Compared with the monoculture group, the bacterial community abundance and structure of JH and YDC were quite different. The relative abundance of Actinobacteriota and Firmicutes was increased in YDC, and that of Acidobacteriota and Myxococcota was increased in JH. According to the redundancy analysis (RDA), pH, total potassium, and soil catalase activity were identified as the main factors influencing the microbial community structure of the intercropping systems. In conclusion, intercropping with JH and YDC increased the relative abundance of the dominant bacterial communities, improved the microbial community structure, and enhanced the soil nutrients and enzyme activities. Therefore, in the future, these two medicinal plants can be used for intercropping with C. oleifera.

Effect of Integrated Nutrient Management on Soil Health, Soil Quality, and Production of Cowpea (Vigna unguiculata L.).

The integrated application of inorganic fertilizers, organic fertilizers, and biofertilizers helps sustainthe nutrient pool and benefits the soil quality, thereby boosting plant health. The effect of different combinations of biofertilizers (consortium biofertilizer [CBF]-non-rhizobial PGPR), inorganicfertilizers, and organic fertilizers on soil health, growth, and yield of cowpea was evaluated by conducting a field experiment. The application of N100FYM + CBF resulted in significantly higher populations of bacteria, fungi, PSB, and diazotroph, as well as soil dehydrogenaseand alkaline phosphatase enzyme activities. However, the application of N100 FYM recorded a significantly higher actinomycetes population. The application of N100 FYM + CBF resulted in significantly higher soil OC, available nitrogen, phosphorus, and potassium. The soil pH was recorded to be highest in control, and soil EC was recorded to be lowest in control. The plant uptake of nitrogen, phosphorus, and potassium was significantly higher with N50 FYM + NP50 + CBF. The root-shoot biomass, number of leaves, nodules/plant, number of pods/plants, pod biomass, pod length, and pod width were significantly higher in treatment having N50 FYM + NP50 + CBF. However, the height of the plant, number of branches, and biomass of leaves werehighest in treatment with N25 FYM + NP75 + CBF. The pod and stover yield were significantly higher in treatment with N50 FYM + NP50 + CBF. The results showed that the integrated application of non-rhizobial PGPR along with organic and inorganic fertilizer helps to improve overall soil health, quality, and plant growth of forage cowpea contributing to an increase in crop yield.

Enhancing sustainable crop production through integrated nutrient management: a focus on vermicompost, bio-enriched rock phosphate, and inorganic fertilisers – a systematic review

Securing a consistent food supply remains a pressing global challenge, particularly for small-scale farmers grappling with obstacles in enhancing agricultural yields, especially in tropical soils. Integrated Nutrient Management (INM) techniques, employing organic manures like vermicompost and bio-enriched rock phosphate, emerge as recommended solutions. Vermicompost is lauded for its nutrient richness and positive soil health impacts. At the same time, bio-enriched rock phosphate serves as a sustainable alternative to conventional phosphorus fertilisers, specifically tailored for tropical soil conditions. Despite individual studies assessing the effects of vermicompost, bio-enriched rock phosphate, and soluble fertilisers on plant growth, a comprehensive overview of their combined application is noticeably lacking. To fill this gap, this study employs the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) method to explore the synergies of combining these elements and their impacts on crop production and the environment. This review is among the first to comprehensively summarize the complexities of combining vermicompost, bio-enriched rock phosphate, and chemical fertilisers on various crops. It thoroughly examines potential advantages, disadvantages, effects on agricultural systems, socio-economic implications, and existing policies governing their usage. Our findings reveal that the combined application of vermicompost, bio-enriched rock phosphate, and soluble fertilisers leads to significant improvements in plant growth, yield, and soil properties. The optimal impact is observed when vermicompost constitutes 25% and soluble fertiliser comprises 75 or 100% of the recommended fertiliser dosage. Moreover, incorporating a mixture of phosphate-solubilizing bacteria (PSB) strains in rock phosphate further enhances its positive effects. Despite these positive findings, we identified gaps in comprehensive approaches addressing socio-cultural dimensions and the lack of literature on prevailing policies regarding vermicompost use in agricultural systems highlighting the need for a more holistic understanding of vermicompost incorporation and a better grasp of the institutional frameworks guiding these practices. However, to secure sustainable crop production, farmers need to integrate vermicompost and biofertilisers with chemical fertilisers. In fostering the adoption of sustainable and inclusive agricultural practices on small rural properties, it is advisable to incorporate agricultural education into farmer training programs.

Tradeoffs among plant yield, nitrate accumulation risk, and potential pathogen: Effects of citric acid and nitrification inhibitors on soil–plant systems

Tradeoffs among plant yield, nitrate accumulation risk, and potential pathogen: Effects of citric acid and nitrification inhibitors on soil–plant systems

Short-term effects of restoration measures on vegetation community and soil characteristics of an Achnatherum inebrians-type degraded alpine grassland in the Eastern Qilian Mountains

The Qilian Mountains constitute an important ecological security barrier in the northwest of China, with a wealth of habitat types and biological species. They have a profound impact on the surrounding area and even the world. However, due to both natural and anthropogenic influences, Achnatherum inebrians is widely distributed in this region, seriously threatening the balance of the grass-soil-livestock ecosystem. To explore appropriate restoration measures of alpine grassland of the Eastern Qilian Mountains degraded by the presence of A. inebrians, we studied the effects of restoration measures on the A. inebrians population, the grassland vegetation community, and soil characteristics following sward ripping (SR) and swarding ripping plus reseeding excellent forage (SREF) in Tianzhu County, Gansu Province; adjacent A. inebrians-type degraded alpine grassland without any measures was the control (CK). The SR and SREF inhibited A. inebrians growth and reproduction, increased the proportion of edible forage and the community species diversity, (especially aboveground biomass and sum of sub-coverage of edible forage by as much as two and three times), and improved soil nutrients and soil quality. The radar analysis showed that SREF had the best effect on the A. inebrians-type degraded alpine grassland. Correlation analysis showed that edible forage community, plant diversity, soil moisture, and available nutrient content were the main factors driving the restoration of this degraded alpine grassland. Implementing measures tailored to local conditions could effectively inhibit the spread of A. inebrians, stimulate edible forage growth, and improve the grassland plant community and soil environment. The results indicated a reasonable method of restoration for this poisonous weed-type degraded grassland and protection of the ecological environment.

Soil Legacies of Tree Species Composition in Mature Forest Affect Tree Seedlings’ Performance

AbstractTrees affect the biotic and abiotic properties of the soil in which they grow. Tree species-specific effects can persist for a long time, even after the trees have been removed. We investigated to what extent such soil legacies of different tree species may impact tree seedlings in their emergence and growth. We performed a plant–soil feedback experiment, using soil that was conditioned in plots that vary in tree species composition in Białowieża Forest, Poland. Soil was taken from plots varying in proportion of birch, hornbeam, pine, and oak. In each soil, seeds of the same four target species were sown in pots. Seedling emergence and growth were monitored for one growing season. To further explore biotic implications of soil legacies, ectomycorrhizal root tip colonization of oak, a keystone forest species, was determined. We found no effect of soil legacies of tree species on the emergence measures. We, however, found a clear negative effect of pine legacies on the total biomass of all four seedling species. In addition, we found relationships between the presence of pine and soil fertility and between soil fertility and root tip colonization. Root tip colonization was positively correlated with the biomass of oak seedlings. We conclude that tree species can leave legacies that persist after that species has been removed. These legacies influence the growth of the next generation of trees likely via abiotic and biotic pathways. Thus, the choice of species in today’s forest may also matter for the structure and composition of future forests.

Effect of AC electric field on enhancing phytoremediation of Cd-contaminated soils in different pH soils

To increase the efficiency of phytoremediation to clean up heavy metals in soil, assisted with alternating current (AC) electric field technology is a promising choice. Our experiments utilized the hyperaccumulator Sedum alfredii Hance and the fast-growing, high-biomass willow (Salix sp.). We investigated the efficiency of AC field combined with S. alfredii—willow intercropping for removing Cd from soils with different pH values. In the AC electric field treatment with S. alfredii—willow intercropping, the available Cd content in acidic soil increased by 50.00% compared to the control, and in alkaline soil, the increase was 100.00%. Furthermore, AC electric field promoted Cd uptake by plants in both acidic and alkaline soils, with Cd accumulation in the aboveground increased by 20.52% (P < 0.05) and 11.73%, respectively. In conclusion, the integration of AC electric fields with phytoremediation demonstrates significant favorable effectiveness.