Purpose Sustained inputs of nitrogen and/or phosphorus from wastewater treatment plants (WWTPs) to aquatic environments lead to an increased risk of eutrophication. The purpose of this study was to analyze the relative proportions of biotic and abiotic processes in the uptake of phosphorus by streambed sediments and their response to exogenous carbon (sodium acetate) concentration gradients, as well

Purpose The aims of the study were to investigate the interaction between fractions of organic matter and polycyclic aromatic hydrocarbons (PAHs) in bottom sediments and to use mussels as passive biomonitors and consensus-based sediment quality guidelines for ecological risk assessment in sediments. Methods Bottom sediment samples were taken from 46 points located in the Rożnów reservoir (Poland).

Purpose Soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) play a vital in plant growth, and their stoichiometric ratios (RCN, RCP, RNP, and RCNP) are important indicators of the elemental balance in the soil ecosystem. However, the effects of land-use change (from natural forest to high-intensity orchards) on dynamics of SOC, TN, TP, and their stoichiometric ratios along the

Purpose Soil organic carbon (SOC), especially the stable SOC, have the important ecological function in the carbon cycle. As a typical stable SOC, soil phytolith-occluded organic carbon (PhytOC) is one of the important mechanisms of long-term soil carbon sink in terrestrial ecosystems. However, the distribution characteristics, accumulation law, and cycle process of soil PhytOC in fragile karst ecosystems

Purpose Soil fertility plays a key role in citrus productivity. Therefore, it is necessary to explore the effects of soil amendments on soil fertility and citrus productivity and estimate carbon fractions’ suitability, which response to soil fertility and citrus productivity. Methods A field experiment in a citrus orchard was conducted containing five treatments: local habit fertilization (LF), special

Purpose Seasonal hypoxia in water bodies can increase levels of reduced chemical species in the hypolimnion as they are released from anoxic bottom sediments. Water-lifting aeration (WLA) is a technology known to solve this problem by elevating near-sediment dissolved oxygen (DO) and increasing mixing in the water column in a canyon reservoir with deep water (>20 m). The influence of WLA in reservoirs

Purposes Establishing accurate geochemical baselines by normalization procedures (NP) is important for distinguishing contaminated soils from the uncontaminated ones. In the areas with intensive anthropogenic influences, geochemical baselines are easily affected by the contaminated soils. The commonly used least squares method is not robust enough because it is sensitive to outliers, resulting in distorted

Purpose Ascertaining soil and associated soil organic carbon (SOC) redistribution induced by erosion and deposition processes is of critical importance to explore SOC dynamics on the landscape. The relationship between landscape scale erosion and deposition and SOC dynamics still has to be clearly described in fragile karst region. Methods The soil profiles of 40-cm depth in relation to different land

Abstract Purpose In most of previous studies about aggregate breakdown caused by water erosion, a critical process that water inevitably fragments the eroded aggregates by water erosion again is generally ignored. This will reduce the accuracy of research results. Hence, alcohol has been added to the collecting device of eroded aggregates to weaken the slaking of eroded aggregates by the researchers

Purpose Desorption of phosphorus (P) bound to iron-containing minerals (Fe-P) is a crucial component of the eutrophication process in lakes. However, the main process and regulation mechanism of iron (Fe) and sulfur (S) on P release is little known because of a lack of in situ high-resolution data. High-resolution measurement evidence is needed to assess the availability and diffusion kinetic process

Purpose Lead (Pb(II)) can be accumulated in soil and transferred to humans via the food chain. Therefore, it is essential to improve Pb(II) immobilization during soil remediation. Materials and methods Nanosized zero-valent iron (nZVI) from green tea extract (tea polyphenols, TPs) was successfully synthesized as an additive reductant. Further, the nZVI was supported on montmorillonite (Mont), resulting

Purpose Seagrasses accelerate sedimentation, release oxygen and organic matter through their roots, and compete with ammonia oxidizers for ammonia/ammonium in surface sediments and overlying water, all of which can influence benthic aerobic nitrification. To understand the effects of seagrass vegetation on benthic nitrification, the heterogeneity of nitrification activities and functional microbial

Purpose Differences in the composition and properties of soil organic matter (SOM) components with different decomposition stages determine their ability and mechanism to sequester heavy metals in contaminated soils. However, very little research has emphasized the adsorption properties of heavy metals on humic acid (HA) versus particulate organic matter (POM). Materials and methods X-ray absorption

Purpose Long-term fertilization is a widely accepted strategy to enhance soil organic (SOC). However, fertilization effects on the stability of aggregate-associated OC remained largely unknown. Thus, stability of aggregate-associated OC was studied through aggregate fractionation, C-mineralization, and 13C NMR analyses. Materials and methods Three aggregates (macro-aggregates, micro-aggregates, and

Purpose The aim of the study was to (1) investigate the distributions of sulfur (S), iron (Fe), and phosphorus (P) in coastal surface sediments under the stresses of high salinity and heavy metals; (2) identify potential sources and the environmental geochemical process of S–Fe mineral accumulation; and (3) elucidate the coupling mechanisms of S–Fe–P in coastal sediments under environmental stresses

Purpose Internal phosphorus (P) input has been proven to be an important cause of eutrophication. The purpose of this study is to explore the process and mechanism of P release from sediments in seasonal hypoxic reservoirs. Material and methods Six sediment cores were collected from Hongfeng Reservoir, one of the largest reservoirs in southwestern China. Incubation experiments were conducted using

Purpose How to predict gully erosion rates was one of the most important issues at present. A model implemented in the Channel Hillslope Integrated Landscape Development (CHILD) model based on the shape factor (Sf) of the plunge pools, which successfully predicted the headcut retreat rates over a long timescale. But whether this model was also valid in the short-term scale? What factors affected the

Purpose At the intersection of land and sea, coastal zones are unstable areas that can suffer intensive coastal erosion or sedimentation. The Yellow River Delta, which has experienced rapid land growth, is of great significance in soil fertility research. Materials and methods To qualitatively and quantitatively analyse the basic soil fertility characteristics of coastal zones, we sampled six soil

Purpose Soil quality can not only affect soil and water conservation, soil nutrient cycling, soil structure, and stability but also impact the agricultural sustainability. The objective of our study was to evaluate the effects of different tillage and straw management methods on the soil quality indicators and peanut yield in a wheat–peanut rotation system in the Huang-Huai-Hai Plain of China. Materials

Purpose The recent literature indicates that, depending on the feedstocks and pyrolysis temperature, biochar can be a good source of nutrients. On the contrary, some biochars are not good sources of available carbon and other nutrients, but their porous structure seems to be a suitable microenvironment for microbial colonization. We investigated the response of soil biological parameters, microbial

Purpose The stability of soil organic matter is a key predictor of changes in management practices due to the progressive decomposition of organic compounds. However, the dynamics of soil compounds and to what extent the composition of microbes controls the process are still unclear. Methods Black soils from Northeast China without fertilizer (CK), soil treated with chemical fertilizer (NPK), NPK plus

Purpose The information on the effects of ZnONPs on soil biological processes and the resulting changes of ecosystem function is limited in wheat straw return agricultural soil. This study investigated the effects of ZnONPs on soil heterotrophic respiration and biochemical properties in wheat straw return farmland soil. Materials and methods An 84-day microcosm incubation experiment was implemented

Purpose Wildfires can have major impacts on water scarcity and water quality linked to off-site transfer of polluting ash and nutrients. Understanding sediment sources in burnt landscapes can help to develop mitigation strategies, especially in catchments planted with introduced species that are prone to fire. We investigated sediment sources activated by post-fire rainfall in a small-forested catchment

Purpose Measuring environmental capacity of total nitrogen (TN) in marine water has become an effective indicator of how much TN is entering the ocean from various sources. However, the TN environmental capacity balance is affected not only by external input but also by removal of TN from water. This removal occurs by numerous mechanisms, among which sedimentation is one that should not be ignored

Purpose Complete ammonia oxidizers (comammox), which convert ammonia to nitrate through nitrite, are a newly discovered nitrifying group. In recent years, comammox Nitrospira have been discovered in various natural and engineered ecosystems. However, little is known about the distribution dynamics of comammox Nitrospira in estuary tidal flat sediments. Materials and methods Chongming eastern tidal

Purpose Roles of bulk and rhizosphere denitrifying bacteria in paddy soil denitrification under straw return conditions are rarely discriminated, limiting our understanding on nitrogen biogeochemistry in soils amended with straw. The objective of this study was to explore the microbial mechanisms accounting for the altered rhizosphere and bulk soil denitrification with straw amendment. Methods In this

Purpose In order to determine the interactive effect of Phyllostachys pubescens (moso bamboo) expansion to adjacent coniferous forest (Cryptomeria japonica, Japanese cedar) on soil fauna communities and soil food web, we conducted a tangible investigation combined with natural abundance isotope analysis to examine how moso bamboo expansion process affects soil faunal composition and underground soil

Purpose An important bottleneck in phytoremediation technologies, which focus on extraction of potentially toxic trace elements, is the low solubility and bioavailability of metals, a handicap that worsens over time. To overcome this barrier, we explored the possibility of using Zn-solubilising bacteria with plant growth-promoting characteristics. Material and methods Zn-tolerant soil bacteria were

Purpose Wetland soils may face more severe water stress under future climate change. Our aim was to assess the change characteristics of wetland soil bacterial community and metabolic potentials under drought and flood conditions. Methods Wetland soil was incubated under five different water environments (including constant moisture at 30%, natural air-dried, and 3 types of flooding depths) by conducting

Purpose Wetland eutrophication is a global ecological problem. Anaerobic oxidation of ammonium (ANAMMOX) and denitrification are the two major pathways of nitrogen removal in wetlands. However, little is known about the associated bacteria that are present around emergent macrophytes and their transcriptional activities. Here, we examine the transcriptional activity of bacteria that perform ANAMMOX

Purpose Phosphorus (P) fertilization methods significantly affect soil P availability, transformation, and crops yield. However, contradictory or paradoxical results are often available, and debates about this issue have never ceased so far. Therefore, the aims of this study are to explore influences of different P application methods on availability and transformation of added P in drip-irrigated

Purpose The slightly exuberant appearance suggests a misleading idea of an insignificant diversity of microorganisms in Cerrado soils. Thus, a review is necessary, gathering essential information on the microbiology of the Cerrado soil, and its biogeochemical processes, as well as the effects of anthropogenic impacts on this important biome. Materials and methods We reviewed studies of microbiota,

Purpose In situ remediation techniques are currently limited for agricultural soil contaminated by heavy metal(loid)s, particularly for alkaline soil. In this study, we applied the amendments (Chinese loess, attapulgites, and composted sludge) to a contaminated alkaline agricultural soil to compare their effectiveness in immobilizing heavy metal(loid)s. Materials and methods Soil was collected from

Purpose The excessive use of nitrogen (N) fertilizer in intensive agriculture has increased nitrate leaching into groundwater, but its impacts on N transformation processes and the associated microbial communities in the deep vadose zone remain unclear. Materials and methods Soil samples from 0–1050 cm depth were collected from a 20-year field experiment with two N fertilization treatments: 0 (N0)

Purpose The impact of dairy farm effluent and manure applications upon gas emissions from soil is of concern for agronomic, ecological, and environmental reasons. Yet it remains unclear how the optimized manure and effluent additions may affect gas (nitrous oxide (N2O), nitric oxide (NO), and ammonia (NH3)) emissions during wheat cultivation. Materials and methods We conducted a field experiment in

Purpose The quality of organic matter influencing sediment nitrate (NO3−) reduction processes in estuarine zones is not well understood. This study aimed to assess the denitrification (DNF), anaerobic ammonium oxidation (ANA), and dissimilatory reduction of nitrate to ammonium (DNRA) in estuarine zones of South Africa, and to understand the effects of organic matter fractions and degradation states

Purpose Microbial inoculation is a promising way to improve soil fertility in an eco-friendly manner. Despite the extensive studies of microbial inoculation used for soil biofertilization, their influences on the soil resident microbial community compositions and functions remain poorly understood. Methods Here, we conducted a 130-day pot experiment to test the effects of single and co-inoculation

Purpose This study aims to investigate the dynamic changes over time in the immobilization efficiency of hydroxyapatite, bentonite, and biochar for Cd and Pb co-contaminated soil given the potential remobilization of immobilized heavy metals for long-term stabilized soils. Materials and methods Hydroxyapatite, bentonite, and biochar were applied only once at 2.5% (w/w) of soil during a 5-year pot experiment

Purpose The successful implementation of a plant protection product depends on its effectiveness against a target species and its safety for the environment. Risk assessment schemes have therefore been devised to facilitate classification and regulation. These guidelines, however, are directed towards chemical substances and are in many cases less suitable for the assessment of products employing microorganisms

Purpose This study aimed to relate the altitudinal and vertical distributions and occurrences of major heavy metals (HMs) to soil physicochemical properties in the riparian soils subject to periodic and intense wet–dry cycles Materials and methods Cadmium (Cd), copper (Cu), and lead (Pb) and their chemical fractions were investigated in the riparian soil (0–40 cm) of the upland and within the water-level-fluctuation

Purpose Significant leaching losses of nitrogen (N) and phosphorus (P) from soil occurred during the summer fallow period of intensive plastic-shed vegetable production systems, which could be resolved by catch crops. Materials and methods We firstly estimated the economic profits and then evaluated the efficiencies of six catch leafy vegetables on reducing N and P leaching losses. Meanwhile, responses

Purpose Soil physico-chemical properties, biomass production, and root density are considered key factors indicating soil health in an agroecosystem. The soil physico-chemical changes and plant growth (e.g., shoot biomass production and root density) in a 6-year cultivation of plant species used as green manure in a sandy soil from Tropical ecosystem, North-eastern Brazil, were investigated between

Purpose Intensive livestock grazing has been associated with an increased risk of soil erosion and concomitant negative impacts on the ecological status of watercourses. Whilst various mitigation options are promoted for reducing livestock impacts, there is a paucity of data on the relationship between stocking rates and quantified sediment losses. This evidence gap means there is uncertainty regarding

Purpose This study investigated the chemical and physical mechanisms associated with the movement of water and salt in saline-alkali soil amended with different types of biochar. Materials and methods Four types of biochar were selected: ordinary laboratory-prepared biochar (BC), acidified biochar (HBC), particle size modified biochar (NBC), and composite modified biochar (HNBC). The physical and chemical

Purpose Soil nitrogen (N) availability plays an important role in determining ecosystem structure and function. However, the variation patterns of soil N availability under different vegetation restoration strategies along climatic gradients in the ecologically fragile karst region of China have been poorly understood. Methods Soil N variables, including total N (TN), inorganic N [ammonium (NH4+) and

Purpose Many industries and agriculture generate huge amounts of wastes either mineral, organic or both, with environmental impact. Some of these residues have the potential to become Technosols when mixed in proper proportions. Degraded terrestrial ecosystems, especially sloping land, show very shallow or no soil left which makes restoration very difficult. Covering such degraded surfaces with Technosols

Purpose This investigation assessed the responses of soil fertility, enzyme activity, and microbial community diversity to soil texture and land use type. Materials and methods The tested soils included five soil textures (sandy loam, medium loam, heavy loam, light clay, and medium clay soils) with two land use types (uncultivated and paddy soils) in the coastal zone of Zhejiang Province, China. Results

Purpose Conversion of coastal mudflats to agricultural soil is one of the most important land use practices in Eastern China. However, effects of soil profile and reclamation time on soil microbial community, which play an important role in soil nutrient cycling, are still poorly documented. Materials and methods Soil profile (0–15 cm, 15–30 cm, 30–45 cm) samples were collected from four sites with

Purpose Nitrous oxide (N2O) measured simultaneously with di-nitrogen (N2) emissions from soils are greatly uncertain due to large temporal and spatial variations. This study aims to report N2O, N2, N2/N2O, 15N-N2O, wheat-maize annual grain yields, and yield-scaled N2O and N2O plus N2 emissions on the responses to different nitrogen (N) fertilizer rates in a winter wheat-summer maize cropping system

Purpose Clay-humic substance complexes play a major role in controlling the mobility of elements and colloids in natural soils. The purpose of the present study is to explore the different reaction mechanisms induced by cations on the humic acid (HA) and montmorillonite (Mt) heteroaggregation and to analyze the binding mechanism of HA-Mt. Materials and methods HA is extracted from soil and colloidal

Purpose Microplastics have become a ubiquitous pollutant in marine, terrestrial and freshwater systems that seriously affects aquatic and terrestrial ecosystems. Common methods for analysing microplastic abundance in soil or sediments are based on destructive sampling or involve destructive sample processing. Thus, substantial information about local distribution of microplastics is inevitably lost

Purpose The aim of this study was to estimate the impact of lake disappearance, groundwater table fluctuations, and some aspects of human pressure on stages of soil cover development in the catchment of Lake Rakutowskie. Materials and methods Research was conducted in soil chronosequence composed of eight soil profiles located in 785-m-long transect. Soils were sampled every 10 cm. Physical and chemical

Purpose Though land use change has been shown to have great influence on soil structure and C storage, little is still known how these effects change over the long term, especially in Africa. Thus, a study was conducted in central highlands of Kenya to evaluate changes in soil aggregates and aggregate-associated C content across four land use types. Methods The four land use types included (1) an undisturbed

Purpose Cereal-based cropping systems under arid and semiarid climates have typically low soil organic matter and fertility, and natural fallowing during summer gap could have negative effects on soil quality and health. We tested an alternative approach of using biochar and leguminous cover crops to replace natural summer fallowing of about 75 days in the wheat-maize-wheat cropping systems with a

Purpose Thermal treatment technologies are generally very effective for the remediation of soils contaminated. For the traditional thermal treatment method of contaminated soil, the heating method from the outside to the inside will inevitably cause a waste of energy, and it may be expensive due to the energy costs. Therefore, it is necessary to find a new heating technology to improve the thermal

Purpose Urbanisation causes changes in land use, from natural or rural to urban, leading to the sealing of soil and the replacement of vegetation by buildings, roads and pavements. The sealing process impacts soil properties and services and can lead to negative consequences for microbial attributes and processes in soil. At present, information about the microbial community following soil sealing

Purpose Though the process and players of nitrification are important in the ecology and biogeochemistry of Arctic fjords; there are very limited studies available on the ecology of ammonia oxidizers. Hence, we studied the abundance, diversity, and niche separation of ammonia oxidizers in the surface sediment of two high Arctic fjords (Kongsfjorden and Krossfjorden) to explore their ecology in the

Purpose Organic mulching is an effective forest management technique that improves the soil environment and promotes plant growth. The rhizosphere is an important interface connecting root systems and soil. However, the rhizosphere effects (REs) after organic mulching are still unknown. Methods We conducted a field experiment in a 15-year-old Ligustrum lucidum forest of urban greening space. Changes