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Based on bibliometric analysis, this paper summarized the research progress of the effects of biochar (BC) on soil physical and chemical properties and provided recommendations for future research. By using appropriate keywords, a total of 1,448 bibliographic records were retrieved from the Web of Science database, and these records were analysed on the basis of criteria, such as authors, keywords, citations, countries, institutions and journals. On the basis of these data, research advances were mapped to identify current scientific trends and the progress made, as well as knowledge gaps. The research began in the year 2010 and accelerated after the year 2015. Yong Sik Ok is the best-known and most productive author in the field. Moreover, China and America are important countries for BC research. Soil Biology and Biochemistry received the highest cocitation rate amongst active journals. Research hotspots can be separated into four distinct clusters, and future research can be summarised in these three directions: (1) the effects of BC mixed with organic and chemical fertilisers on crop growth and nitrogen use efficiency; (2) the response to a series of soil health problems, such as soil erosion and salinisation, by waste management to produce BC for bioremediation; and (3) the effects of BC on soil physicochemical properties from the perspective and mechanism of soil bacterial communities and other microorganisms. [ABSTRACT FROM AUTHOR]

Litter decomposition is essential for nutrient and chemical cycling in terrestrial ecosystems. Previous research on in situ litter decomposition has often underestimated its impact on soil nutrient dynamics and allelopathy. To address this gap, we conducted a comprehensive study involving both field and greenhouse experiments to examine the decomposition and allelopathic effects of the invasive Solidago canadensis L. in comparison with the native Phalaris arundinacea L. In the field, a 6-month litter bag experiment using leaf litter from S. canadensis and P. arundinacea was conducted across three community types: invasive, native, and mixed. Seed germination tests were also performed to investigate the allelopathic effects of decomposing litter. In the greenhouse, a pot experiment with lettuce as a bioindicator was performed to examine the allelochemical inputs from litter decomposition over various time intervals (0, 30, 60, 120, and 180 days). Subsequently, a soil–plant feedback experiment was carried out to further evaluate the effects of decomposing litter on soil biochemistry and plant dynamics. The findings of this study revealed that S. canadensis litter decomposed more rapidly and exhibited greater nitrogen (N) remaining mass compared with P. arundinacea in both single and mixed communities. After 180 days, the values for litter mass remaining for S. canadensis and P. arundinacea were 36% and 43%, respectively, when grown separately and were 32% and 44%, respectively, in mixed communities. At the invasive site, the soil ammonia and nitrate for S. canadensis increased gradually, reaching 0.89 and 14.93 mg/kg by day 120, compared with the native site with P. arundinacea. The soil organic carbon for S. canadensis at the invasive site also increased from 10.6 mg/kg on day 0 to 15.82 mg/kg on day 120, showing a higher increase than that at the native site with P. arundinacea. During the initial decomposition stages, all litters released almost all of their allelochemicals. However, at the later stages, litters continued to input nutrients into the soil, but had no significant impact on the soil carbon (C) and N cycling. Notably, litter-mediated plant–soil feedback facilitated the invasion of S. canadensis. In conclusion, this study highlights the significance of litter decomposition as a driver of transforming soil biochemistry, influencing the success of invasive S. canadensis. [ABSTRACT FROM AUTHOR]

Background and Aims: Over the last few decades, rampant nitrogen fertilization has exacerbated soil acidification in agricultural ecosystems. To counteract this, liming has become an essential technique for rehabilitating fertility in acid-degraded agricultural soils. Our research aimed to shed light on the response of ammonia oxidizers to liming in acidic soils within a controlled rice paddy experiment. We conducted a pot experiment with rice, featuring three different treatments: a control with only soil, a low dolomite dose (LD), and a high dolomite dose (HD). Various soil properties were investigated throughout the study. Under flooding, soil pH values rose across the treatments, from 5.4 in the control to 6.8 in HD. Ammonium and nitrate levels peaked in the HD treatment, reaching 30 and 22 mg kg−1, respectively. Similarly, dissolved organic carbon and microbial biomass carbon surged at mid-season aeration, hitting highs of 101 and 30 mg kg−1, respectively, in the HD treatment. Ammonia-oxidizing bacteria (AOB) and archaea (AOA) were responsive to dolomite-lime application, with distinct reactions; AOB abundance and potential nitrification rates were positively affected by higher lime doses, whereas AOA numbers decreased over time and with dolomite application. Additionally, soil enzymes such as urease, catalase, invertase, phenol oxidase, and phosphatase also increased progressively, mirroring the rise in soil pH. This study identified increased soil pH as the critical factor influencing various soil parameters, especially the balance between AOA and AOB populations. Both AOB and AOA were sensitive to liming; AOA decreased while liming stimulated AOB abundance. [ABSTRACT FROM AUTHOR]

A pot experiment was carried out to evaluate the remediation potential of Brassica juncea and Sorghum bicolor in the decontamination of soil polluted with heavy metals such as copper, lead, tin, and zinc along with polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and heavy hydrocarbons. Two composts obtained from different composting processes were tested as biostimulating agents. At the end of the trial, the effect of plant/compost combinations on soil microbial composition, contaminant removal, biochemical indicators, and plant biomass production was determined. The results highlighted that compost addition improved plant biomass despite slowing down plants' removal of organic and inorganic contaminants. In addition, compost partially enhanced the soil biochemical indicators and modified the relative abundance of the rhizosphere microorganisms. Sorghum showed better mitigation performance than Brassica due to its higher growth. The soil fertility level, the choice of plant species, and microbial richness were found fundamental to perform soil remediation. In contrast, compost was relevant for a higher crop biomass yield. [ABSTRACT FROM AUTHOR]

The history that follows will show that the limits of (in)humanity are malleable and readily shifted. Whirled in the chaos of life, ordinary people may suddenly be transformed into monsters, and later, may return calmly to their former nature. It remains unclear why these limits prove so diffuse. Dr. Hans Beutelspacher, whose life story took us ten years to reconstruct, traced this path in both directions, and thus came to embody yet another mystery of the human mind. The possessor of an educated and inventive intelligence, he toyed with monstrous behaviour during World War II, before returning just as effortlessly to his «human» and even benevolent state, later developing a prominent career in the field of soil biochemistry. [ABSTRACT FROM AUTHOR]

Introduction: Sugarcane/soybean intercropping with reduced nitrogen (N) addition has improved soil fertility and sustainable agricultural development in China. However, the effects of intercropping pattern and N fertilizer addition on the allocation of photosynthesized carbon (C) in plant-soil system were far less understood. Methods: In this study, we performed an 13CO2 pulse labeling experiment to trace C footprints in plant-soil system under different cropping patterns [sugarcane monoculture (MS), sugarcane/soybean intercropping (SB)] and N addition levels [reduced N addition (N1) and conventional N addition (N2)]. Results and discussion: Our results showed that compared to sugarcane monoculture, sugarcane/soybean intercropping with N reduced addition increased sugarcane biomass and root/shoot ratio, which in turn led to 23.48% increase in total root biomass. The higher root biomass facilitated the flow of shoot fixed 13C to the soil in the formof rhizodeposits. More than 40% of the retained 13C in the soil was incorporated into the labile C pool [microbial biomass C (MBC) and dissolved organic C (DOC)] on day 1 after labeling. On day 27 after labeling, sugarcane/soybean intercropping withN reduced addition showed the highest 13C content in the MBC as well as in the soil, 1.89 and 1.14 times higher than the sugarcane monoculture, respectively. Moreover, intercropping pattern increased the content of labile C and labile N (alkaline N, ammonium N and nitrate N) in the soil. The structural equation model indicated that the cropping pattern regulated 13C sequestration in the soil mainly by driving changes in labile C, labile N content and root biomass in the soil. Our findings demonstrate that sugarcane/soybean intercropping with reduced N addition increases photosynthesized C sequestration in the soil, enhances the C sink capacity of agroecosystems. [ABSTRACT FROM AUTHOR]

Selection of a land plot is one of the first and most important stages during realization of the vineyard project. The final decision at this stage is determined by many factors, including the cost of the land plot, its logistical parameters, tourist attractiveness, etc. The most important among them is the suitability of the plot for grape cultivation, determined by a combination of soil, climatic, and orographic conditions, which are combined in the concept of terroir in the production practice of viticulture and winemaking. An integral assessment of the soil component of the terroir of test plots located in contrasting physical-geographical conditions of France (communes of Le Bignon and Domme) and Russia (villages of Fruktovoe and Beregovoi) was performed. The optimal list of analyzed soil properties based on the parameters taken into account when choosing rootstock varieties—the design solution that most depends on soil conditions—was determined in the course of the work. Then, the procedure of compression of the information on the soil component of the terroir of test plots was performed, and locally oriented weight coefficients were calculated. According to the results of the average integral assessment in the 1-m-deep layer of soil profiles, the following ranked sequence of test plots from the best soil conditions to the worst ones was obtained: the village of Beregovoi (score 0.84), the commune of Le Bignon (score 0.70), the village of Fruktovoe (scores 0.66 and 0.65), and the commune of Domme (score 0.63), the values of which can be compared with other factors at the stage of making a decision on planting vineyards. [ABSTRACT FROM AUTHOR]

Savannas are characterized by the co-occurrence of two different plant life forms: grasses and trees. Herbivory plays a major role in the balance between grasses and trees in savanna ecosystems. The present study aimed to investigate the impact and interactions between long-term (i.e. 20 years) herbivory and/or its exclusion and plant life form on the soil biochemistry of a protected semi-arid savanna ecosystem in the Kruger National Park (KNP), South Africa. To study the effects of herbivory on soil properties, herbivore exclosures (fully fenced areas, partially fenced areas, and an unfenced area) were used in conjunction with plant life form (trees and grasses) were considered. Interaction effects of herbivory and plant life form on soil pH, electrical conductivity (EC), total nitrogen (TN), total carbon (TC), available phosphorus (available P), exchangeable cations (K+, Na+, Mg2+ and Ca2+) cation exchange capacity (CEC), organic matter (OM) and total microbial activity were determined on savanna soils in the Nkuhlu exclosures, KNP. Exclosures where herbivores were present had significantly higher soil pH, The presence of herbivores caused an increase in soil pH, EC, exchangeable Na, CEC, and OM. The influence of the tree canopy was significantly more pronounced in elevating total C and N, exchangeable K+, Mg2+ and Ca2+, CEC and OM than observed in the open grassland zones across all exclosures. The two-way interaction between herbivory and plant life form resulted in significant decreases in TN, TC, exchangeable K, Na and Mg in open grassland areas outside of herbivore exclosures where large animals had direct access, as compared to areas within the exclosures which was protected from animal entry herbivory. This data can be used by national parks as an indicator to increase their knowledge of environmental issues relating to maintaining and preserving landscape features of savannas. [ABSTRACT FROM AUTHOR]

Nitrogen (N), an indispensable mineral nutrient element for plant growth and development, is a major limiting source of productivity in many terrestrial ecosystems. Soil organic nitrogen (SON) is a crucial form of nitrogen (N) in the N cycle within terrestrial ecosystems, acting as either a "source" or a "sink" for environmental N release. In order to illustrate the research trends, evolution process and hotspots of SON, a bibliometric analysis was used to analyze 906 documents based on the ISI (Institute of Scientific Information) Web of Science (WoS) database. The results indicated that (1) the number of published papers on SON research showed a wavy growth from 2000 to 2022 and the research has entered a mature development period; China has been increasing its number of publications and has long been in the lead; (2) the most productive institutions and authors in this subject area are in the USA and China, with the Chinese Academy of Sciences being the key institution performing such research; (3) in the sample, Soil Biology and Biochemistry, Science of the Total Environment, and Biogeochemistry are the leading international journals that have played a key role in the evolution of the field and have laid a solid foundation for future research; (4) the characteristics and maintenance of SON in farmland and SON migration in small watersheds under forest conversion have become research hotspots. Through the in-depth analysis of SON research, this paper provides a better understanding of the development trends of SON over the past 20 years, which can also provide reference for future research. [ABSTRACT FROM AUTHOR]

Nanoproducts are gaining more importance in scientific society and the industrial sphere thus emerging as a new contaminant of the terrestrial systems including soil biology and biochemistry. Organic carbons are crucial in the growth and development of microorganisms and plants. Soil rich in organic carbon is considered as fertile. Enzymes like β-glucosidase, xylanases, and proteases are responsible for the last stage of complex organic matter degradation and the release of free carbon in the soil. Many of these enzymes may be considered as an important aspect for the policies pertaining to soil protection in the future keeping nanoparticle mediated toxicity of soil as a vital parameter. Due to accumulation of nanomaterials in soil, these activities may affect the function of enzymes and nutrient availability, but the detailed investigations are under developing phase. In this mini review, the authors have tried to establish a relationship between the negative impacts of nanoparticles on soil enzymes as a future concern. [ABSTRACT FROM AUTHOR]

Soils and agriculture are inextricably linked, in the past as well as today. The Pacific islands, which often represent organized gradients of the essential soil-forming factors of substrate age and rainfall, represent excellent study systems to understand interactions between people and soils. The relationship between soil characteristics and indigenous agricultural practices are well documented for some locations, but there is a paucity of data for much of the region. Given the extent of ecological adaptation that has been documented, specifically for Hawai'i, new Pacific datasets are expected to provide important insights into indigenous agricultural practices. To contribute to this discussion, we analyzed patterns in soil chemistry and vegetation in the Manu'a islands of American Samoa. Soils were sampled along transects that crossed through precontact settlement zones in the upland of Fiti'uta on Ta'ū island, a location characterized by young (<100 ky) volcanic substrates and very high (>3800 mm y−1) annual rainfall. Soils were analyzed for several soil fertility properties that have been proposed as predictors of intensive rainfed tuber production in Hawai'i and Rapa Nui. Surveys of remnant economic plants were conducted to assess patterns of past land use. Soils demonstrated moderate values of soil fertility as measured by pH, base saturation, exchangeable calcium, and total and exchangeable phosphorus, despite the high rainfall. Previously identified soil fertility indicators had some application to the distribution of traditional agriculture, but they also differed in important ways. In particular, low exchangeable calcium in the soils may have limited the agricultural form, especially the cultivation of tubers. Significant shifts in both soil parameters and remnant economic crops were documented, and alignment suggests cropping system adaptation to soil biochemistry. Archaeological samples combined with surveys of relict vegetation suggest that agroforestry and arboriculture were key components of past agricultural practices. [ABSTRACT FROM AUTHOR]

Background and aim: Coastal marshes and wetlands hosting blue carbon ecosystems have shown vulnerability to sea-level rise (SLR) and its consequent effects. In this study, we explored the effects of waterlogging and elevated salinity on the accumulation and allocation of photosynthetic carbon (C) in a widely distributed species in marsh lands. Methods: The plant–soil mesocosms of Phragmites australis were grown under waterlogging and elevated salinity conditions to investigate the responses of photosynthetic C allocation in different C pools (plant organs and soils) based on 13CO2 pulse-labeling technology. Results: Both waterlogging and elevated salinity treatments decreased photosynthetic C fixation. The hydrological treatments also reduced 13C transport to the plant organs of P. australis while significantly increased 13C allocation percentage in roots. Waterlogging and low salinity had no significant effects on 13C allocation to rhizosphere soils, while high salinity (15 and 30 ppt) significantly reduced 13C allocation to soils, indicating a decreased root C export in saline environments. Waterlogging enhanced the effects of salinity on the 13C allocation pattern, particularly during the late growing season. The responses of flooding and elevated salinity on C allocation in plant organs and rhizosphere soils can be related to changes in nutrient, ionic concentrations and microbial biomass. Conclusion: The adaptation strategy of P. australis led to increased C allocation in belowground organs under changed hydrology. Expected global SLR projection might decrease total C stocks in P. australis and alter the C allocation pattern in marsh plant-soil systems, due to amplified effects of flooding and elevated salinities. [ABSTRACT FROM AUTHOR]

The use of liquid formulations―prepared from naturally available farm wastes―has increasingly gained popularity in recent years; however, it remains unclear how these amendments influence the rhizosphere soil biochemistry, particularly in aerobic rice. In this study, we reformulated the traditional liquid manure (Jeevamrutha) with microbial consortia as liquid bioformulation (LBF), and evaluated its potential effect (when applied with or without NPK-fertilizers) on soil biochemical properties and nutrient availability at different stages of crop growth. Six treatments were tested: (i) absolute control, (ii) conventional practice (CP), LBF applied twice at 2000 L ha–1 with (iii) 100% recommended dose of fertilizer (RDF) through a multi-split fertigation (LBF+NPK100), (iv) 75% RDF (LBF+NPK75), (v) 50% RDF (LBF+NPK50), and (vi) LBF alone. The results showed that soil microbial biomass carbon, total bacterial and fungal load, dehydrogenase, urease, and acid phosphatase activities were significantly (p <.05) higher in the LBF co-applied plots, particularly at the panicle initiation and maturity stages of rice. However, actinomycetes and alkaline phosphatase showed an irregular trend with the growth stages. The rhizosphere soil microbial index (RSMI) values were significantly higher under LBF co-applied treatments over the CP, signifying the improvement of soil quality. Grain yield with LBF+NPK75 increased by 30.3−37.8% and 19.3−32.4% for the summer and rainy seasons, respectively, compared with the CP. Combining LBF with NPK-fertigation had more long-lasting effect on soil N and P availability. Therefore, our findings suggest that substituting about half of RDF with LBF could bring promising agronomic and soil ecological benefits to the rice production under aerobic conditions. [ABSTRACT FROM AUTHOR]

A field experiment was conducted during the winter seasons of 2017–18 and 2018–19 at Uttar Banga Krishi Viswavidyalaya, Cooch Behar, West Bengal, India to study the impacts of tillage and herbicides on weeds, biochemical properties of soil, and productivity of wheat. Tillage systems had similar weed diversity, density and weed control index (WCI), whereas there were significant effects due to weed control treatments. Two hand weeding had superior weed control followed by Glyphosate 41% SL @ 2.5 L ha−1 + (Sulfosulfuron 75% + Metsulfuron methyl 5% WG) @ 40 g ha−1 and (Sulfosulfuron 75% + Metsulfuron methyl 5% WG) @ 40 g ha−1, as this treatment resulted in flat weed diversity, density, highest WCI, upsurge in grain yield and furthermore enriched biochemical properties of soil. Conventional tillage (CT) system recorded lower weed density than reduced tillage (RT) and zero tillage systems. Convincingly, low weed density, dry matter and highest WCI were recorded in two hand weeding at 20 and 40 days after sowing followed by herbicidal treatments at 40 and 60 DAS. Higher grain yield obtained with CT (3.48 t ha−1 and 3.88 t ha−1) was statistically at par with RT (3.12 t ha−1 and 3.59 t ha−1). Among the weed control treatments, hand weeding at 20 and 40 DAS generated more grain yield (3.61 t ha−1) during 2017–18 and Glyphosate 41% SL 2.5 l ha−1 + (Sulfosulfuron75% + Metsulfuron methyl 5% WG) @ 40 g ha−1 generated higher grain yield (3.90 t ha−1) during 2018–19. Soil organic carbon, soil available N, P2O5, and exchangeable K2O were found non-significant due to tillage systems. Expressively higher soil organic carbon, soil available N, P2O5, and exchangeable K2O were recorded with (Sulfosulfuron 75% + Metsulfuron methyl 5% WG) @ 60 g ha−1 and (Sulfosulfuron 75% + Metsulfuron methyl 5% WG) @ 40 g ha−1. In CT, higher bacterial and actinomycetes colonies were found which was at par with RT. Herbicidal treatments recorded a higher number of bacterial and actinomycetes colonies and a lower number of fungal colonies. [ABSTRACT FROM AUTHOR]

Shrubs are expanding in grassland ecosystems across the world, yet their influence on the spatial heterogeneity of soil phosphorus (P) transformation has seldom been investigated. We conducted grid sampling to a soil depth of 1.2 m in a grazed alpine meadow dominated by grass patches and four shrub species to analyze the spatial distributions of soil pH and total soil P and its acid-soluble (representing inorganic P) and acid-insoluble (organic) P fractions. Heterogeneities of soil pH and total, acid-soluble and acid-insoluble P were all visible to the depth of 1.2 m across the plot. The total P stock decreased in the upper 0.4 m of soil, but increased in the lower 0.8 m, under shrubs compared to grasses, resulting in only negligible differences in the total soil P stock in the entire 1.2 m profile between vegetation patch types. The acid-soluble P stock decreased under shrubs throughout the profile, responding to the lowering of soil pH by shrubs, while the acid-insoluble P stock increased in the lower 0.8 m, under shrubs compared with grasses. Soil acid-insoluble P under shrubs increased at the expense of acid-soluble P. These features led to significantly higher proportions of acid-insoluble P in the total P across the 1.2 m soil profile under shrubs (66–71 %) compared to grasses (55 %), associated with the lowered soil pH in shrubby patches. We conclude that shrubification alters the biochemistry of the soil P pool to a depth of at least 1.2 m. The lowered soil pH under shrubs drives the transformation of soil P from inorganic to organic forms in alpine meadows. The altered biochemistry of the soil P pool suggests a rapid release of available P, which supports primary productivity. We emphasize the importance of deep soil sampling in investigating the effects of shrubification on soil P cycling. [Display omitted] • Heterogeneities of soil pH and inorganic and organic P are visible to 1.2 m depth. • Soil organic P under shrubs increases at the expense of inorganic P. • Shrubs enhance soil P transformation from inorganic to organic form. • Enhancement of soil P transformation by shrubs is driven via lowering soil pH. • Total P stock in the 1.2 m soil is almost unaffected by shrubs. [ABSTRACT FROM AUTHOR]

Invasive alien plants such as Reynoutria spp. can drastically affect the composition of plant communities. Yet, whether and how these species also affect soil physicochemical properties and microbial functioning is still an unresolved question in the literature. Using a space-for-time substitution approach comparing invaded to uninvaded adjacent plots, we estimated the impacts of Reynoutria on soil biochemistry across nine contrasted sites in France by measuring soil carbon content, nutrient availability and enzyme activities. Soil under Reynoutria displayed higher carbon, nitrogen and phosphorus contents but no differences were detected regarding enzyme activities between invaded and uninvaded sites. Moreover, the magnitude of Reynoutria 's effects differed depending on local conditions, with greater effects when total carbon and phosphorus-related enzymes were relatively low. These data highlight that changes in soil nutrient availability might be primarily due to direct effects of Reynoutria on soil properties and microbial functioning. Higher impacts were observed in soils with low-nutrient status, suggesting a 'niche construction ability' of Reynoutria. Our results underscore the necessity of considering the context-dependency of Reynoutria on soil biochemistry and highlight that the impact of alien species belowground functioning depends on initial soil conditions. [Display omitted] • We compared soil conditions in Reynoutria -invaded plots to riparian plots. • Reynoutria spp. positively affected carbon, nitrogen and phosphorus contents. • Reynoutria spp. did not affect enzyme activities. • The magnitude of Reynoutria 's effects differed depending on local conditions. • Higher impacts in poor soil conditions suggested a 'niche construction ability'. [ABSTRACT FROM AUTHOR]

In the Kruger National Park (KNP), the lower slopes of catenas have open patches referred to as sodic patches. Fire and herbivores are dominant mediators of vegetation in sodic patches. The effect of fire and herbivores on soil properties of sodic patches remains largely understudied. Moreover, the co-existence of trees and grasses and how they influence savanna soils is an important but poorly understood phenomenon in ecology. Therefore, the present study aimed to determine the influence of 20 years of fire, herbivores, vegetation type, and their interaction on soil biochemistry of sodic patches on the Nkuhlu exclosures in the Kruger National Park, South Africa. We found a higher main effect of fire on available phosphorus, cation exchange capacity, and soil organic matter. The presence of herbivores caused an increase in soil exchangeable cations (K+, Ca2+, Na+, and Mg2+), organic matter, cation exchange capacity, and microbial activity. Tree canopies had a higher effect on total nitrogen, exchangeable Ca and Mg, soil organic matter, and cation exchange capacity than open grassland zones. Our results indicate that changes in vegetation structure due to fire and herbivores and their secondary impact on soil properties should be taken into consideration in managing savannas. Moreover, fire and herbivores play an important role in the maintenance of vegetation type (trees and grasses) in sodic patches. [ABSTRACT FROM AUTHOR]

Black soldier fly larvae (Hermetia illucens L. BSFL) bioconversion is a promising biotechnology for food waste recycling, yet little is known about how BSFL vermicompost affects soil health in terms of element availability and related microbial response. In this work, a field soil experiment for luffa (Luffa cylindrica (L.) Roem.) growth was conducted to examine the impacts of BSFL vermicompost (BV, 9750 kg ha−1, equal to total N input rate of chemically treated soil (CK)) on soil biochemistry and bacterial communities. Relative to CK, application of BV significantly increased total soil carbon by 149% and enhanced catalase and urease activity by 59.2% and 16.2%, respectively. BV increased the degree of aromaticity and humification in dissolved organic matter (DOM) in soil by 28.6% and 27.3%, respectively, compared to CK treatment. Among bacterial communities in soil, Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria were the phyla that showed the most substantial alteration in response to BV. Redundancy analysis further revealed that the bacterial community structure was affected by DOM and total phosphorus. Functional analyses indicated that BV enhanced xylanolysis (55.4%) and nitrogen fixation (46.3%), but inhibited nitrification (59.8%). BSFL vermicompost input might effectively prevent the harm of soil borne pathogens (e.g., wilt). Moreover, these function groups strongly correlated with Clostridiales, Actinomycetales, and Nitrospirales. Our study reveals that BSFL vermicompost promoted soil nutrient availability, microbial community succession, and biochemical function optimization, which is conducive to the popularization and application of BSFL vermicompost in the field of soil health. Key points: • Vermicompost enhanced catalase and urease levels while increased DOM aromaticity. • Vermicompost enriched Bacteroidetes and Firmicutes and improved soil health. [ABSTRACT FROM AUTHOR]

Smooth brome (Bromus inermis Leyss.) is an invasive cool-season grass that has spread throughout the Great Plains of North America. The species is considered one of the most widespread exotic grasses that has successfully invaded both cool-season and warm-season native prairies. In the prairies where it has invaded, there has often been a total elimination of native species and an overall homogenization of ecosystems. Smooth brome has greater competitive abilities compared to many native grasses and can foster their total elimination in many instances. The greater competitiveness can be partially attributed to its ability to alter the soil and hydrological properties of a site. It is a deep-rooted rhizomatous grass species that thrives in nitrogen-enriched soil, and since its leaf tissue decomposes faster than native species, it in turn increases the soil nitrogen level, causing positive plant-soil feedback. Moreover, smooth brome is able to transport the required nutrients from older plants to the newer progenies invading new nutrient-depleted areas, making it a potent invader. However, the impact of smooth brome is not limited to soil biochemistry alone; it also affects other ecosystem components such as the movement and behavior of many native arthropods, thereby altering the overall population dynamics of such species. Thus, smooth brome invasion poses a serious threat to the remnant prairies of the Great Plains, and efficient management strategies are urgently needed to control its invasion. Control measures such as mowing, grazing, burning, and herbicide application have been effectively used to manage this species. However, due to the widespread distribution of smooth brome across North America and its adaptability to a wide range of environmental conditions, it is challenging to translate the management strategies from one area to another. [ABSTRACT FROM AUTHOR]

After several pandemics over the last two millennia, the wildlife reservoirs of plague (Yersinia pestis) now persist around the world, including in the western United States. Routine surveillance in this region has generated comprehensive records of human cases and animal seroprevalence, creating a unique opportunity to test how plague reservoirs are responding to environmental change. Here, we test whether animal and human data suggest that plague reservoirs and spillover risk have shifted since 1950. To do so, we develop a new method for detecting the impact of climate change on infectious disease distributions, capable of disentangling long‐term trends (signal) and interannual variation in both weather and sampling (noise). We find that plague foci are associated with high‐elevation rodent communities, and soil biochemistry may play a key role in the geography of long‐term persistence. In addition, we find that human cases are concentrated only in a small subset of endemic areas, and that spillover events are driven by higher rodent species richness (the amplification hypothesis) and climatic anomalies (the trophic cascade hypothesis). Using our detection model, we find that due to the changing climate, rodent communities at high elevations have become more conducive to the establishment of plague reservoirs—with suitability increasing up to 40% in some places—and that spillover risk to humans at mid‐elevations has increased as well, although more gradually. These results highlight opportunities for deeper investigation of plague ecology, the value of integrative surveillance for infectious disease geography, and the need for further research into ongoing climate change impacts. [ABSTRACT FROM AUTHOR]

The field experiment was conducted during the winter season of 2016-17 at the experimental site of Agroforestry Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand. Poplar and eucalyptus were intercropped with different wheat varieties (UP-2526, UP-2565, UP-2628, and DPW-621-50). After harvesting the wheat crop, the soil sampling was performed to determine the soil parameters like electrical conductivity (EC), organic carbon and the minerals content. Nitrogen, phosphorus and potassium content and other biochemical constituents were higher in the agroforestry system as compared to the open farming system. A high soil pH (7.53) was found in an open farming system and lower pH in an agroforestry system. Soil EC in the agroforestry system was slightly higher than the open farming system. Organic carbon was maximum (1.33%) under the poplar agroforestry system compared to the eucalyptus based agroforestry system. Overall, this study determines the effect of poplar and eucalyptus based agroforestry systems on soil biochemistry. [ABSTRACT FROM AUTHOR]

Understanding the relationship between durum wheat genotypes and soil biochemistry under salt stress plays a key role in breeding for yield superior genotypes. Thus, microbial biomass carbon (MBC) and nitrogen (MBN), the activity of three selected enzymes including dehydrogenase (D-ase), alkaline phosphatase (Alk-ase), and protease (P-ase), and available phosphorus (available P) and nitrogen (available N) were assessed. Two landraces and two improved varieties were tested under two salinity levels of water irrigation (0.3 and 12 dS m-1). Soil sampling was carried out at five durum wheat growth stages. The soil biota-genotype interaction seems to affect the biological (MBC, MBN, and enzymatic activities) and chemical (available P and N) traits. The microbial activity of rhizospheric soil was higher at the tillering and flowering stages. Under saline conditions, 'Maali' (improved variety) and 'Agili Glabre' (landrace) showed the best belowground inputs (e.g., MBC, MBN, enzymatic activities, available P and N) and grain yield (GY) performance. Under the same conditions, four soil biochemical indicators of GY of tolerant genotypes (i.e., 'Maali' and 'Agili Glabre') were determined as available N, P-ase, available P, Alkase, and D-ase. Stepwise analysis revealed that predictive variables depended on growth stages. Overall, MBC, available N, Alk-ase, and P-ase were the variables that mainly contributed to predicting GY in saline environments. In conclusion, the results suggested a specific interaction between plant genotype roots and soil microbes to overcome salt stress. Thus, soil biological components should acquire more importance in plant salinity tolerance studies. [ABSTRACT FROM AUTHOR]

Soil pollution due to toxic elements (TEs) has been a core environmental concern globally, particularly in areas with developed industries. In this study, we sampled 300 surface (0-0.2 m) soil samples from Yuyao City in eastern China. Initially, the geo-accumulation index, potential ecological risk index, single pollution index, and Nemerow composite pollution index were used to evaluate the soil contamination status in Yuyao City. Ordinary kriging was then deployed to map the distribution of the soil TEs. Subsequently, indicator kriging was utilized to identify regions with high risk of TE pollution. Finally, the positive matrix factorization model was used to apportion the sources of the different TEs. Our results indicated that the mean content of different TEs kept the order: Zn > Cr > Pb > Cu > Ni > As > Hg ≈ Cd. Soil pollution was mainly caused by Cd and Hg in the soil of Yuyao City, while the content of other TEs was maintained at a safe level. Regions with high TE content and high pollution risk of TEs are mainly located in the central part of Yuyao City. Four sources of soil TEs were apportioned in Yuyao City. The Pb, Hg, and Zn contents in soil were mainly derived from traffic activities, coal combustion, and smelting. Meanwhile, Cu was mainly sourced from industrial emissions and atmospheric deposition, Cr and Ni mainly originated from soil parental materials, and Cd and As were produced by industrial and agricultural activities. Our study provides important implications for improving the soil environment and contributes to the development of efficient strategies for TE pollution control and remediation. [ABSTRACT FROM AUTHOR]

Different soil amendments are applied to improve soil properties and to achieve higher crop yield under drought conditions. The objective of the study was to investigate the role of biochar for the improvement of wheat (Triticum aestivum L.) growth and soil biochemical properties under drought conditions. A pot experiment with a completely randomized design was arranged with four replications in a wire house. Drought was imposed on two critical growth stages (tillering and grain filling) and biochar was applied to the soil 10 days before sowing at two different rates (28 g kg-1 38 g kg-1 Soil samples were collected to determine the soil properties including soil respiration and enzymatic parameters after crop harvesting. Results showed that water stress negatively affects all biochemical properties of the soil, while biochar amendments positively improved these properties. Application of biochar at 38 g kg-1 provided significantly higher mineral nutrients, Bray P (18.72%), exchangeable-K (7.44%), soil carbon (11.86%), nitrogen mineralization (16.35%), and soil respiration (6.37%) as a result of increased microbial activities in comparison with the 28 g kg-1. [ABSTRACT FROM AUTHOR]

[Display omitted] • Seasons, forest types, and ground cover together alters soil microbial biomass C, N, and enzymes. • Quercus sp. and C. torulosa forests have better soil quality indicators than P. roxburghii forests. • Rainy season with optimum conditions for microbial activity promotes SMBC, SMBN, and enzymes. • Moss cover with higher nutrient and moisture retention attributes to higher microbial biomass. • Soil organic matter and moisture were important controlling factors for SMBC, SMBN, and enzymes. Soil microbial biomass (SMB) is a key storehouse of carbon and nitrogen, driving biogeochemical cycles. Understanding soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN), and soil enzymes is crucial for global nutrient cycling. Soil biochemistry is linked to seasonal and vegetation-related soil changes, but little is known about how season, moss cover, and forest types collectively affect SMB and enzymes. In this context, our study examined five temperate forest types (Pinus roxburghii, Quercus leucotrichophora, Q. floribunda, Q. semecarpifolia, and Cupressus torulosa) and two ground cover types (moss-covered and bare soil) to assess their impacts on SMBC, SMBN, and enzymatic activity in the Indian Central Himalayas during the rainy and winter seasons. SMBC and SMBN were quantified using the chloroform fumigation-extraction method, while enzymatic activity was assessed using established protocols. Forest types, ground cover, and seasons significantly influenced SMBC and enzymatic activity (p < 0.01). Forest and ground cover had substantial effects on SMBN (p < 0.01), while seasons had negligible effects (p > 0.05). Biochemical properties showcased higher values under moss-covered soil in the rainy season and bare soil in winter. C. torulosa forests, followed by Quercus -dominated forests, exhibited superior SMB and enzymatic activities compared to P. roxburghii forests. SMBC and SMBN varied across forest types, ranging from 58.54 to 1913.75 µg/g and 16.77 to 137.81 µg/g, respectively. Soil organic matter and moisture were key abiotic factors influencing soil biochemical properties. The results indicate that moss-covered soil in C. torulosa and Quercus -dominated forests appears promising for maintaining SMB and enzymatic activity, and should be preferred in forest management plans to improve microbial diversity and soil quality. Overall, this study deepens our understanding of soil enzymatic activity and microbial biomass dynamics in carbon and nitrogen cycling, and highlights the importance of moss ground cover as hotspots for ecosystem functioning. [ABSTRACT FROM AUTHOR]

High-spatiotemporal-resolution leaf area index (LAI) data are essential for sustainable agro-ecosystem management and precise disturbance detection. Previous LAI products were primarily derived from satellite data with limited spatiotemporal or spectral resolutions, which could be overcome with the use of Sentinel-2. While hybrid methods that integrate PROSAIL simulations with machine learning offer advantages in extracting high-spatiotemporal-resolution LAI from Sentinel-2, they still face challenges due to confounding factors related to canopy structure, leaf biochemistry, and soil background. To reduce impacts of these confounders, we developed an efficient hybrid method for Sentinel-2-based LAI retrieval. Our approach consists of random forest models trained on simulated datasets generated by PROSAIL-5B with two refinements: variable canopy fraction of fully senescent leaves (FS) and soil bidirectional reflectance factor (BRF) simulated by Brightness-Shape-Moisture (BSM) model. We corrected canopy BRF using near-infrared reflectance of vegetation (NIR V) and vegetation cover within mixed pixels (V C). For validation, we used ground measurements across different vegetation types from the Copernicus Ground Based Observations for Validation (GBOV) and Korea flux (KoFlux) sites during 2019–2023. Our results showed that coupling BSM and FS with PROSAIL-5B simulations improved hybrid LAI estimates, reducing RMSE by 10.8%–73.8%. Utilizing NIR V and V C to correct canopy BRF better quantified LAI in most vegetation types, with RMSE reduced by 15.3%–64.8%. Our hybrid method showed robust agreement with ground validation data from GBOV (R2 = 0.88, RMSE = 0.71) and KoFlux (R2 = 0.80, RMSE = 0.75). Overall, our method (R2 = 0.58–0.93, RMSE = 0.04–0.83) outperformed both the benchmark Sentinel Application Platform (R2 = 0.11–0.85, RMSE = 0.28–1.67) and data-driven (R2 = 0.09–0.85, RMSE = 0.29–0.93) algorithms in producing precise seasonal LAI data at finer resolutions. Our findings underscore the potential of the proposed hybrid method for high-spatiotemporal-resolution LAI retrieval across diverse ecosystems. [Display omitted] • Canopy fraction of senescent leaves and soil BRF model enhanced PROSAIL simulations. • Correcting BRF by NIR V and accounting for mixed pixels increased sensitivity to LAI. • Sentinel-2 BRF/NIR V , BRF M and BRF M /NIR VM outperformed BRF for hybrid LAI estimation. • Our hybrid method outperformed other relevant high-resolution LAI estimation methods. • Prior knowledge of LAI ranges and leaf angles improved hybrid LAI estimation. [ABSTRACT FROM AUTHOR]

Silicon (Si), a quasi-essential element for plants, is abundant in the soil typically as insoluble silicate forms. However, plants can uptake Si only in the soluble form of monosilicic acid. Production of monosilicic acid by rock-weathering mostly depends on temperature, pH, redox-potential, water-content, and microbial activities. In the present review, approaches involved in the efficient exploration of silicate solubilizing bacteria (SSB), its potential applications, and available technological advances are discussed. Present understanding of Si uptake, deposition, and subsequent benefits to plants has also been discussed. In agricultural soils, pH is found to be one of the most critical factors deciding silicate solubilization and the formation of different Si compounds. Numerous studies have predicted the role of Indole-3-Acetic Acid (IAA) and organic acids produced by SSB in silicate solubilization. In this regard, approaches for the isolation and characterization of SSB, quantification of IAA, and subsequent Si solubilization mechanisms are addressed. Phylogenetic evaluation of previously reported SSB showed a highly diverse origin which provides an opportunity to study different mechanisms involved in Si solubilization. Soil biochemistry in concern of silicon availability, microbial activity and silicon mediated changes in plant physiology are addressed. In addition, SSB's role in Si-biogeochemical cycling is summarized. The information presented here will be helpful to explore the potential of SSB more efficiently to promote sustainable agriculture. • Silicate solubilizing bacteria plays important role in silicon biogeochemical cycle. • Silicon is beneficial for plants, poultry birds, domestic animals and human. • Silicate solubilizing bacteria has potential to be used as biofertilizer. • Silicon fertilization has great environmental concerns. • Mechanism involved in silicate solubilization with bacterial activities. [ABSTRACT FROM AUTHOR]

Recent research shows that earthworms can alter defense traits of plants against herbivores and pathogens by affecting soil biochemistry. Yet, the effects of invasive earthworms on defense traits of native plants from previously earthworm‐free ecosystems as well as the consequences for multitrophic interactions are virtually unknown.Here we use a combination of an observational study and a complementary experimental study to investigate the effects of invasive earthworms on leaf defense traits, herbivore damage and pathogen infection in two poplar tree species (Populus balsamifera and Populus tremuloides) native to North American boreal forests.Our observational study showed that earthworm invasion was associated with enhanced leaf herbivory (by leaf‐chewing insects) in saplings of both tree species. However, we only detected significant shifts in the concentration of chemical defense compounds in response to earthworm invasion for P. balsamifera. Specifically, leaf phenolic concentrations, including salicinoids and catechin, were lower in P. balsamifera from earthworm‐invaded sites.Our experimental study confirmed an earthworm‐induced reduction in leaf defense levels in P. balsamifera for one of the defense compounds, tremulacin. The experimental study additionally showed that invasive earthworms reduced leaf dry matter content, potentially increasing leaf palatability, and enhanced susceptibility of trees to infection by a fungal pathogen, but not to aphid infestation, in the same tree species.Synthesis. Our results show that invasive earthworms can decrease the concentrations of some chemical defense compounds in P. balsamifera, which could make them susceptible to leaf‐chewing insects. Such potential impacts of invasive earthworms are likely to have implications for tree survival and competition, native tree biodiversity and ecosystem functioning. [ABSTRACT FROM AUTHOR]

Integrated crop, livestock, and forestry systems (iCLF) have been widely heralded as a sustainable farming method in comparison to conventional pastures. However, intensive soil use and management modify ecosystem function, particularly biogeochemical cycling. The aim of this study was to determine whether there are changes in soil chemistry or biochemistry after the conversion of pasture into iCLF in the Brazilian Cerrado. Additionally, we compared three iCLF areas initiated 3, 5, and 8 years before this study to test the effect of time since conversion to iCLF (age) on soil chemistry and biochemistry and on microbial carbon (C). Conventional pasture and native Cerrado soils were used as controls. Microbial C and biochemical activity were dependent on the plant cover and age of the iCLF, but soil physicochemical properties were sensitive only to the agroecosystem type. Enzyme activity and microbial C were higher in native Cerrado soils, followed by iCLF and pasture soils, respectively. There was an inverse relationship between iCLF age and microbial C and β-Glucosidase and phenol oxidase activities. The results suggest that the response of the microbial community depends on the soil composition and the iCLF age. Nutrient cycling in iCLF increases with age of the system and varies by management subtype within the iCLF (i.e., forestry or grazing areas). The implementation of iCLF changes soil conditions, which generates a positive response in the microbial community. The adoption of iCLF increases microbial activity and enhances soil quality over short–medium timescales (5 years). [ABSTRACT FROM AUTHOR]

Degradation of soil micronutrient fertility status is an increasingly serious problem damaging the sustainability of modern agriculture. In this article, an attempt has been made to present some of the significant features of boron (B) in relation to soil nutrition including soil biochemistry and plant root uptake kinetics. Interests in B research have been sparked by the problem of deficiency and toxicity resulting from shortage and oversupply of the nutrient. Both deficiency and toxicity of B may be related to the total concentration of B in the soil, however, these problems arise from the chemical forms of B present in the soil, particularly its solubility, and availability to plants. The natural soil conditions as well as different soil-management practices have a marked influence on the fractions of B present in the soil and its availability. [ABSTRACT FROM AUTHOR]

Decomposition of animal bodies in the burial environment plays a key role in the biochemistry of the soil, altering the balance of the local microbial populations present before the introduction of the carcass. Despite the growing number of studies on decomposition and soil bacterial populations, less is known on its effects on fungal communities. Shifts in the fungal populations at different post-mortem intervals (PMIs) could provide insights for PMI estimation and clarify the role that specific fungal taxa have at specific decomposition stages. In this study, we buried pig carcasses over a period of 1- to 6-months, and we sampled the soil in contact with each carcass at different PMIs. We performed metabarcoding analysis of the mycobiome targeting both the internal transcribed spacer (ITS) 1 and 2, to elucidate which one was more suitable for this purpose. Our results showed a decrease in the fungal taxonomic richness associated with increasing PMIs, and the alteration of the soil fungal signature even after 6 months post-burial, showing the inability of soil communities to restore their original composition within this timeframe. The results highlighted taxonomic trends associated with specific PMIs, such as the increase of the Mortierellomycota after 4- and 6-months and of Ascomycota particularly after 2 months, and the decrease of Basidiomycota from the first to the last time point. We have found a limited number of taxa specifically associated with the carrion and not present in the control soil, showing that the major contributors to the recorded changes are originated from the soil and were not introduced by the carrion. As this is the first study conducted on burial graves, it sets the baseline for additional studies to investigate the role of fungal communities on prolonged decomposition periods and to identify fungal biomarkers to improve the accuracy of PMI prediction for forensic applications. [ABSTRACT FROM AUTHOR]

The effect of the endocrine disruptor nonylphenol on the biological activity of loamy soddy-podzolic soil (Eutric Albic Retisol (Abruptic, Loamic, Aric, Ochric)) was studied in model experiments. The upper horizons of loamy soddy-podzolic soil sampled in Leningrad oblast were the object of this study. The number of soil microorganisms, the activity of soil enzymes, and soil respiration were determined with the methods commonly used in soil microbiology and biochemistry. The content of nonylphenol in soil samples was determined using high-performance liquid chromatography. Soil contamination with nonylphenol was shown to cause time- and dose-dependent changes in the activity of the pool of nitrogen, carbohydrates, and redox enzymes and increases the basal respiration. The results obtained are an important stage necessary for risk assessment of soil contamination with alkylphenols, and can be used in the development of a remediation methodology for soils contaminated with endocrine disruptors. [ABSTRACT FROM AUTHOR]