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Coastal wetland soils exposed to crude oil exploration activities were assessed using microbiological and chemical procedures in the wet and dry seasons. The bacteria isolated from the impacted wetland soils included species of the genera Acinetobacter, Alcaligenes, Citrobacter, Azotobacter, Bacillus, Cellulomonas, Flavobacterium, Micrococcus, Proteus, Pseudomonas, Sarcina, Serratia and Staphylococcus. In addition, species of the genera Nitrobacter, Nitrosomonas and Rhizobium were isolated from the non-impacted soils. Total heterotrophic bacterial counts (THBC) in the wet and dry seasons ranged from 7.1 ± 0.4 to 8.6 ± 0.2 Log₁₀CFU g‾¹ and 3.7± 0.04 to 5.4 ± 0.1 Log₁₀CFU g‾¹ for the control and impacted soils respectively. The counts in control was 1.6 to 1.9 times higher than the impacted soil and the difference was significant at p = 0.05. The nitrifying bacteria (NB) associated with the impacted soil were the most adversely affected. There was 2.11 to 139 times higher concentration of the different heavy metals in the impacted soil than the control and 1.13 to 1.26 x 104 times higher Total petroleum hydrocarbon in the impacted soils in both seasons and these differences were significant (p = 0.05). Dehydrogenase activity was 2.8 to 3.1 times higher in the control soils compared to the impacted soil whereas Phenol oxidase was 15.14 to 15.75 times higher in the impacted soils in both seasons. This study indicates that Exploration and Production activitiesi in the coastal wetlands if not carried out according to specified guidelines by the environmental control agencies can result in the reduction of beneficial soil bacterial population and diversity, high concentrations of heavy metals, petroleum hydrocarbon and decreased dehydrogenase activity at impacted explored wetland site. It also revealed non-impacted regions of this explored wetlands not within oil pipe-line routes are fit for agricultural use.

Wetlands played an important role in human development and nature nutrient store for rice cultivation. Spatial techniques have gained importance in monitoring wetland changes. The study aimed to assess wetland soils for rice production using spatial techniques. The area was sample using stratified grid sampling. Nutrient availability and rice suitability were assessed in ArcGIS 10.6 environment. The soil was characterized into Eutric fluvaquent (Soil Survey Staff, 2010) and correlated as fluvisols in the World Reference Base system. The results of the land cover changes showed that built-up, waterbody, and farmland have increased by 39, 18, and 29%, respectively, and 13% decrease was observed in vegetation. The study concluded that soils of the studied area varied from marginally (75%), not suitable (20%), and permanently not suitable (5%) for rice production. Therefore, without proper assessment and management of these studied soils, rice production will continue to be futile.

The spatial distribution and environmental risk assessment of eight hazardous elements in wetland soils in Yellow Sea coastal area of China were investigated. The concentrations of As, Hg, Pb, Cd, Cu, Cr, Zn, and Se varied between 6.35-46.14, 0.004-0.05, 18.90-62.07, 0.17-3.76, 11.34-76.79, 21.52-80.88, 39.25-136.86, 0.002-0.16 mg/kg, respectively. The spatial distributions analysis demonstrated that the high levels of As, Pb, Cd, and Zn were in Sheyang area. The results of correlation and PCA indicated that natural and anthropogenic source were major sources for Pb, Cr, Cu, Zn, and Se. As and Cd were from industrial and agricultural sources, and Hg was from natural source. The Cd indicated that 84% of sites experienced moderate and considerable contamination. The PER indices indicated that 68% of sites experienced considerable and high ecological risk. This study suggested that more attention should be paid to hazardous elements contamination of wetland soils in eastern China.

Deicing salt runoff is a cause of freshwater salinisation in many regions. Studies in uplands indicate that soil properties affect storage and movement across the landscape of salt and dissolved or...

Wetland soils of the Maputaland Coastal Plain do not exhibit the redox morphology typically associated with extended periods of water saturation. The aim of this paper was to determine if the addit...

The Greater Khingan Mountains (GKM) regions have the second-largest areas of permafrost in China and serve as sinks of heavy metals like mercury (Hg) and arsenic (As). However, to date, we lack detailed information on Hg and As reserves, sources, and pollution assessment in the region, and this may bring increasing uncertainty when studying Hg and As cycle. By investing Hg and As contents of soil, plant, and litter samples from 22 typical wetlands in the GKM, we found that the average Hg content was 0.11 mg/kg in the soil, higher than the soil background value. The geo-accumulation index (Igeo) showed that Hg pollution degree ranged from mild to moderate grade. The average soil As content was 16.1 mg/kg. Hg and As storage in wetland soils, vegetation biomass, and litter were estimated to be 4.32 mg/m2 and 995 mg/m2, 159 μg/m2 and 494 μg/m2, and 13.9 μg/m2 and 113 μg/m2, respectively. About 61% As was from endogenous sources contribution, and about 84% Hg was derived from exogenous sources. A positive correlation was observed between Hg in the litter and temperature and the precipitation-to-temperature ratio. This implied that Hg accumulation in the litter should be paid more attention to considering current climatic warming in the GKM.

The following synthesizes studies investigating plant and soil responses to increased inundation in order to support ecosystem restoration efforts related to the alteration of natural wetland hydrodynamics. Specific topics include hydrologic regimes, soil response to inundation, and implications for vegetation communities exposed to increased water depths. Results highlight the important interactions between water, soils, and vegetation that determine the trajectory and fate of wetland ecosystems, including the development of feedback loops related to marsh degradation and subsidence. This report then discusses the knowledge gaps related to implications of inundation depth, timing, and duration within an ecosystem restoration context, identifying opportunities for future research while providing source materials for practitioners developing restoration projects.

The inland wetland soils of Obukiyo, Oju Local Government Area of Benue State, Nigeria were evaluated for the production of rice. The physical, chemical and morphological features of the soils were matched with the requirements of the crop (rice), and the overall suitability rating of the soils was obtained using limitation method. Unit 1 soils were rated as marginally suitable (S3) for rice production due to their drainage condition being ustic moisture regime. Units III and IV soils were considered moderately suitable (S2) on account of water availability and nutrient status while unit ll soils which occupied the lowest elevation with endo saturation and high clay content were rated as highly suitable (S1) for rice production.

Soils of the Maputaland Coastal Plain are naturally grey, do not contain any redoximorphic features, and are therefore problematic to interpret during wetland delineation. This study was consequent...

Soil color patterns are essential to understand hydrologic regime and biogeochemical processes in wetland ecosystems. Munsell Soil Color Chart (MSCC) has been traditionally and predominantl...

El corredor Ocuiltzapotlan-Macultepec constituye una zona con potencial para el crecimiento urbano, por su cercania a la ciudad de Villahermosa Tabasco, esto ha provocado intensos cambios de uso de suelo en su area periurbana que afectan las funciones ambientales de sus recursos naturales. Por ello, el objetivo de la investigacion fue analizar los cambios de uso de suelo, ocurridos entre los anos 2000-2017, asi como el impacto que causan a algunas funciones ambientales de las areas periurbanas en dicho corredor. Mediante analisis de imagenes se identif icaron los usos de suelos, se calcularon las tasas de cambios de uso y se determinaron sus efectos sobre el almacenamiento de carbono y regulacion de los flujos hidricos. Los resultados indican que los usos urbano y pastizales crecieron en 2.27 y 2.26% respectivamente, mientras que los forestales y humedales decrecieron en 11.48 y 1.09% respectivamente. El almacenamiento de carbono edaf ico se estima en 92.4±5.1, 73.2±2.8 y 220.4±4.6 Mg C ha-1 para los usos pastizal, forestal y humedales respectivamente. El compartimento aereo del uso forestal almacena 63.27 Mg C ha-1, que se suman al carbono edaf ico, alcanzando las 136.47 Mg C ha-1, que hacen de este uso de suelo, el segundo almacen de C mas importante, solo despues del humedal. Se concluye que el mayor impacto ambiental ocasionado por el cambio de uso de suelo del area periurbana del poligono estudiado es la reduccion de humedales, por ser estos las principales areas de almacenamiento de carbono y de regulacion de los flujos hidricos.

Soil properties have a significant influence on solutes redistribution in the soil vadose zones. The aim of this study was to assess the relevance of soil properties for solute transport characteristics in degraded wetland soils using 72 undisturbed soil columns from two experimental fields located in Robinia pseudoacacia (CH) and Tamarix chinensis (CL) communities. Combining soil column tracer experiments, all experiments were conducted under the same initial and boundary conditions using Brilliant Blue FCF as a conservative tracer. Solute transport characteristics were described by four measures of dye solution steady infiltration rate of effluents, dye solution concentration of effluents, soil column dye staining patterns, and cumulative dye solution leaching. Numerical modeling by the dual-permeability model in HYDRUS-1D was used to simulate the proportion of cumulative dye solution leaching from soil macropore flow. This study showed that basic soil properties exhibited a significant difference at CH site and at CL site. Dye solution steady infiltration rate of effluents at CH site decreased with soil depth, but increased at first and then decreased with soil depth at CL site. Dye solution concentration of effluents both at CH site and at CL site decreased nonlinearly with soil depth. Soil column dye staining patterns were significantly different among different soil locations, indicating the largest dark blue staining domains from soil depth of 0-10 cm at CH site and 20-40 cm at CL site. The proportion of cumulative dye solution leaching from soil macropore flow was from 37.6 to 61.1% at CH site, whereas from 0 to 99.9% at CL site. Basic soil properties played inconsistent roles in solute transport characteristics. The understanding of soil properties and its correlation with solute transport characteristics is the first step for degraded wetland restoration and development. Some alternative solutions of wetland restoration are proposed for managers.

Trichoderma isolates were collected from wetland soils in different areas of China. Combined analyses of morphological characteristics and phylogenetic analyses by partial translation elongation factor 1 alpha (TEF1-α) and RNA polymerase II subunit b (RPB2) revealed five new Trichoderma species, namely, Trichoderma macrofasciculatum, T. shangrilaense, T. nordicum, T. vadicola, and T. hailarense. T. macrofasciculatum and T. shangrilaense belonging to the Polysporum Clade were isolated from wetland soils collected from Sichuan and Yunnan Provinces. The conidiation of T. macrofasciculatum typically appeared in white pustules in concentric rings on PDA or MEA, and its conidia had two or more guttules. Conidiation of T. shangrilaense formed white pustules with irregular shape and size, and its conidia were mostly obovoid and smooth. Trichoderma vadicola, T. nordicum, and T. hailarense belonging to the Viride Clade were collected from Shandong Province, Beijing Municipality, and Inner Mongolia Autonomous Region, respectively. The phialides of T. nordicum lageniform were curved on PDA, and its conidia were globose to obovoidal and large. The aerial mycelium of T. vadicola formed strands and floccose mat. The colonies of T. hailarense cannot form conidia on PDA, and the conidia of T. hailarense on other media were obovoid and delicately roughened.

This study assessed carbon storage potential in terms of total carbon (TC) and total carbon stocks (TC stocks) in soils of four forested wetlands in Northern Virginia along with associated soil physicochemistry [e.g., soil pH, bulk density (Db), and gravimetric soil moisture (GSM)]. The study sites were selected across two vastly different degrees of urbanization (urban [U]; non-urban [N]) and the two main physiographic provinces of the region (Piedmont; Coastal Plain). Soils were sampled and analyzed at three depth intervals (0-10cm; 10-20cm; 20-30cm). No significant differences were found in TC (3.07 ± 0.31% [U]; 3.82 ± 0.40%; [N]) or TC stocks (2.81 ± 0.35 kg∙m− 2 [U]; 3.58 ± 0.28 kg∙m− 2 [N]) between urbanization degrees (p > 0.05). There was no significant difference in TC stocks by physiographic province (p > 0.05), however, Coastal Plain wetland soils had higher TC than the Piedmont wetlands (4.32 ± 0.41%; 2.57 ± 0.22%, p b and GSM were significantly different along urbanization degree and physiography, and were highly correlated to TC, being able to estimate the total variability of TC to a significant degree (R2 = 0.39 and R2 = 0.47, all p

Wetland soils are dominated by anaerobic conditions induced by soil saturation and flooding. This chapter reviews the chemical and physical parameters of soils, particularly freshwater wetland soils, that influence their ability to effectively treat wastewater. Soils may remove wastewater constituents by ion exchange/nonspecific adsorption; specific adsorption/precipitation; and complexation. To maximize the utility of constructed wetlands to treat wastewater, they must be designed and built to emulate natural wetland ecosystem processes. Wetland processes can often enhance removal of a given wastewater constituent, and specific goals should be identified and design criteria developed to meet those goals. The chapter provides an overview of the major pools, intrasystem transformations, and fluxes for N, P, and S in freshwater wetlands along with specific applications involving these and other important contaminants. The challenge facing us in applied ecology is to construct wetlands with optimal retention capacities for removing and storing contaminants.

Background: Disentangling the biogeographic patterns of rare and abundant microbial sub-communities is essential in order to understand the generation and maintenance of microbial diversity with respect to the functions they provide. However, little is known about ecological assembly processes and environmental adaptation of rare and abundant microbial sub-communities across large spatial-scale wetlands. Using Illumina sequencing, we investigated the taxonomic and phylogenetic β-diversity of rare and abundant bacterial and fungal sub-communities in Qinghai-Tibet Plateau wetland soils. Additionally, we determined environmental breadths and phylogenetic signals of ecological preferences of rare and abundant microbial sub-communities, and investigated community assembly processes of microbial taxa. Results: We found that both taxonomic and phylogenetic similarities of rare and abundant microbial sub-communities attenuated with geographical distance. Based on threshold indicator taxa analysis and Blomberg’s K statistic, abundant microbial taxa exhibited broader environmental thresholds and stronger phylogenetic signals for ecological traits than rare microbial taxa. The strong correlations between community compositional dissimilarity and phylogenetic distance of rare microbial sub-communities also revealed that rare taxa may be more sensitive to environmental changes. In addition, the rare microbial sub-communities exhibited closer phylogenetic clustering compared with abundant microbial sub-communities. The null model analysis revealed that dispersal limitation belonging to stochastic process dominated ecological assembly of abundant bacterial sub-community, and rare and abundant fungal sub-communities; variable selection belonging to deterministic process governed community assembly of rare bacterial taxa. Neutral model analysis and variation partitioning analysis further confirmed that abundant microbial sub-communities were less environmentally constrained. Soil ammonia nitrogen was the crucial factor in mediating the balance between stochasticity and determinism of both rare and abundant microbial sub-communities, as reflected by distinct differences in stochastic process with higher ammonia nitrogen content.Conclusions: Abundant microbial sub-communities may have better environmental adaptation potential and are less dispersed by environmental changes compared with rare microbial sub-communities. Our findings extend knowledge of the adaptation of rare and abundant microbial taxa to ongoing environmental change and could facilitate prediction of biodiversity loss caused by global climate change and increasing human activity in wetlands of the Qinghai-Tibet Plateau.

Hydrologic changes modify microbial community structure and ecosystem functions, especially in wetland systems. Here, we present 24 metagenomes from a coastal freshwater wetland experiment in which we manipulated hydrologic conditions and plant presence. These wetland soil metagenomes will deepen our understanding of how hydrology and vegetation influence microbial functional diversity.

The Qinghai-Tibetan Plateau (QTP), as the third pole, has recently experienced unexpected heavy metal pollution. However, few were available on heavy metal pollution and source apportionment in regions near South Asia, where the economy is currently experiencing rapid development. This paper evaluated heavy metal pollution in wetland soils along the Yarlung Tsangbo River (YTR), the largest river in the QTP. Results indicated minor contamination levels of Cu, Pb, Zn, Hg, As, Mn, and Cr. However, Cd pollution was serious and was the main pollutant. Nemero synthesis index values (PN) were relatively high and ranged from 4.54 to 10.47 caused by high loading from Cd and Zn. Roughly 92% Pb, 89% Cr, and 89% Mn were from natural sources while 86% Cd and 61% Zn were from anthropogenic sources in wetland soils along the YTR. Differences in heavy metal contents and sedimentation rates were accentuated by the metal accumulation rates of each site. Cd, Zn, and Hg accumulation rates were estimated to 0.966 mg m−2 year−1, 0.187 g m−2 year−1, and 0.061 mg m−2 year−1 in the 1800s and increased to 5.351 mg m−2 year−1, 1.144 g m−2 year−1, and 0.263 mg m−2 year−1 in the 2000s, respectively. This implied unexpected heavy metal pollution in wetland soils along the YTR basin and more attention should be paid to avoid the risk of heavy metal pollution here.

Wetlands are important sites for the biogeochemical cycles of macro and microelements, because the presence of the water induces faster chemical and transport processes in the soils which occur as intensive diurnal and seasonal fluctuations of the soil parameters and element-content. Vegetation is also varied basically because of the (often fluctuating) water level, which makes it possible to study these different ecotopes in a relatively small area.We chose our long-term study site – a meadow formed by a local depression of the surface – near Ceglédbercel, Hungary in 2010. Three different vegetation patches were separated governed by the following species (in order of the influence of water): 1 – Agrostis stolonifera; 2 – Carex acutiformis, Carex flacca, Carex vulpina; 3 – Phragmites australis. Microclimatic and soil-representing parameters were measured in each patch: air temperature, evaporation, strength of wind and incident solar radiation; soil temperature, pH and redox potential of the soil solution. We also analyzed the main elements and element forms of the soil solution regularly: NO3-, NO2-, NH4+, PO43-, Mn, Fe, K, Na, Mg, Ca and emitted N2O, CH4 gas fluxes of the soil.Our main hypothesis was that different plant species generate measurable differences and heterogeneities in the bulk soil. This is shown best by the run of the redox potential which often seemed to ignore the effect of water-gradient because of the regulating ability of plants in the rooting zone. The occurrence and concentration of nitrogen forms are very redox-sensitive; thus they are seemingly good indicators of the state of the soil. Somewhat surprisingly, diurnal cycles (caused by the plants’ alternating photosynthetic activity) rarely occurred among the measured parameters and concentrations. One of those rare occurrences was the emission of gaseous N2O, which reached its maximum in the afternoon and almost stopped before dawn. Our long-term experimentation also caught some interesting anomalies (e. g. accidental destruction of the vegetation) thus we managed to record the effect of these environmental changes on the soil and the most environment-sensitive elements of the soil proved to be the nitrogen-forms, with Fe and K.

The biogeochemical reactors are apparatus constructed to evaluations in controlled environments. When well-designed can be environmental technologies for in situ monitoring, as well as methodological support for ex situ analysis. The various models are based on knowledge in chemical engineering and includes chemical, physical and biological concepts, as well as the possible interactions between these basic fronts study. The objective of this work is to expose the possibilities of use of reactors in biogeochemical studies of degradation of organic pesticides in flooded soils and propose a design methodology for tests which have focused on anaerobic systems and degradation of organic pesticides.

Although an important sink for contaminants including metals, wetland soils can release metals and thus cause a secondary pollution when environmental condition changes. Metals in wetland soils are influenced by a variety of environmental factors, including soil property, topography, wetland type, and plant species. However, the degree of importance of these environmental factors to wetland soil metals has not yet been clearly explained. In this study, the effect of these environmental factors on soil metal concentrations (i.e., Cr, Ni, Cu, Zn, As, Cd, and Pb) was explored in Poyang Lake wetland. Correlation, redundancy, and variance decomposition analyses were employed. The results indicate that the concentrations of Cu, Pb, Cd, Cr, and Zn were higher than their background values. Statistical analysis showed that all environmental factors explained 55.90% of the total variance (either p

Sixteen polycyclic aromatic hydrocarbons (PAHs) were quantified by GC/MS in 30 soil samples of Liaohe estuarine reed wetland. The total concentrations of 16 PAHs ranged from 235 to 374 ng g−1, and seven carcinogenic PAHs concentrations were in the range of 83–109 ng g−1. A probabilistic carcinogenic potential for three age groups (including children, teenagers, and adults) exposed to soil PAHs via three pathways was quantitatively calculated based on Monte Carlo simulations. The 95th percentiles carcinogenic risks of PAHs for children, teenagers, and adults were 7.80 × 10−8, 4.03 × 10−8, and 1.14 × 10−7, respectively. The carcinogenic risk levels were all below 10−6, indicating no potential for cancer development. Dermal contact and accident ingestion of soil were the dominant exposure pathways to soil PAHs. BaP and DBahA were the major contributors to carcinogenic risk in this study. Sensitivity analysis demonstrated that exposure duration and PAH concentrations in soil were the key exposure parameters in calculating carcinogenic risk. Results from this study will provide valuable information for potential scientific evaluation and prevention for carcinogenic risk exposed to soil PAHs.

Gleying and enhancement of hydromorphism in wetland soils due to Fe(III) reduction entail a series of degradation processes. The resistance of wetlands to degradation can be calculated from the content of potentially reducible iron, Fe(III)pr, which is found from the van Bodegom equation taking into account the contents of oxalate-soluble iron Feox and dithionite-soluble iron Fedit in the soil. In addition, this makes it possible to distinguish relict and actual gleysols. The van Bodegom equation is applicable to soils from which the oxalate solution extracts only amorphous and poorly crystallized iron compounds, which are quickly reduced by Fe-reducing bacteria. These soils have a low proportion of Fe(II) (no more that 15% of the total iron), as well as an accumulative profile distribution of Feox. The van Bodegom equation is unsuitable for calculating the Fe(III)pr content in soils with a high proportion of Fe(II) and a nonaccumulative profile distribution of Feox.

This study determines the corrosion rate and percent weight loss of mild steel buried in soils of the Niger Delta Area of Nigeria. Six geologic zones representing the upland and wetland soils were used for the assessment. The corrosion rates of mild steel in these soils were monitored to assess the extent of corrosion. However, the upland soils (Odagwa, Ogoni, Ahoada and Omoku) were more resistant to corrosion than the wetland (Kaiama and Elebele) soils. The corrosion rate of mild steel at the 24th month was in the following order of corrosivity: Elebele > Kaiama > Omoku > Ahoada > Ogoni > Odagwa. The percent weight loss was higher at the 24th month, with the highest values found at the Meander Belt Deposits of Elebele. Alternately, the Coastal Plain Sands were found to have the least percent weight loss with the lowest value recorded at Odagwa site at the 24th month. The percent weight loss at the 24th month is in the following order: Elebele > Omoku > Kaiama > Ahoada > Ogoni > Odagwa. The variation in corrosion rate and weight loss of mild steel buried in the different soil types is caused by the aquic moisture regime of the soils, anthropogenic activities carried out, microorganisms present in the soils, and also, the physico-chemical properties of the soils.

Microplastics (MPs) are widespread in the environment including coastal wetlands. The influence of different types and intensities of human activities on the occurrence of MPs in coastal wetlands is still unknown. The aim of this study was to investigate the distribution of MPs and the contribution of human activities in different areas of Yellow River Delta wetland. MPs were widely detected in different areas of the wetland even in the protection area with little human activities. Direct human activities resulted in more severe MPs contamination in the protection area than the tourism area. In the soil of different areas, the MPs abundances ranged from 136 to 2060 items/kg. The concentrations of polyethylene terephthalate (PET) ranged from 536 to 660 μg/kg, and the concentrations of polycarbonate (PC) ranged from 83.9 to 196 μg/kg. The MP abundances of the three areas had significant correlations with PET concentrations. These results indicate that the direct influence of human activities has much greater contribution than indirect influence. These results also suggest that PET concentration can be used as a potential marker of MPs contamination in wetland soils.

While the Munsell Soil Color Chart (MSCC) is the most frequently used, well-established field method for reading soil color, the Nix Color Sensor (NCS) is an inexpensive, app-based alternative that can complement or potentially substitute for the MSCC. Soils were collected and their colors were measured from four forested sites across Northern Virginia within the Chesapeake Bay Watershed using both the MSCC and NCS. Three MSCC variables and 15 NCS variables were collected in the field; a methodology was established to use these "measured" (M) variables to derive 9 NCS calculated (C) variables. A stepwise correlation identified NCS variables most suitable for relating the NCS to each of the MSCC attributes: hue (H), value (V), and chroma (CM). Ultimately, H, V, and CM were deemed to be best represented by HRGB calculated from the RGB color space (ρ = 0.56), L from the CIE-Lab color space (ρ = 0.73), and ẑ = Z/(X + Y + Z) from the XYZ color space (ρ = -0.80), respectively (p < 0.001). The corresponding explanatory powers of final NCS variables (i.e., HRGB, L, and ẑ) for H, V, and CM were 26%, 54%, and 62%, respectively (p

The rare earth elements (REE) along with iron and manganese distribution in ochre-precipitates and wetland soils in a passive system for acid mine drainage treatment (Jales, Portugal) was studied. The results obtained by instrumental neutron activation analysis showed a higher incorporation of the light REE (particularly La and Ce) by the ochre-precipitates resulting from the mine water-limestone interaction. These fluffy materials influence the entrance of the first wetland where a correlation between Fe and La and Ce was found. Then Mn phases appear to play a more important role controlling REE distribution in the remaining area of the wetland soils., Thanks to EDM (Empresa de Desenvolvimento Mineiro, S.A.) for providing access to the water treatment plant, and to the staff of the Portuguese Research Reactor (RPI) of CTN/IST. C2TN authors gratefully acknowledge the FCT (the Portuguese Science and Technology Foundation) support through the UID/Multi/04349/2013. This work is co-funded by European Union through the European Regional Development Fund, based on COMPETE 2020 (Programa Operacional da Competitividade e Internacionalização), project ICT (UID/GEO/04683/2013) with reference POCI-01-0145-FEDER-007690 and national funds provided by FCT., info:eu-repo/semantics/publishedVersion

Deciphering the role of soil organic matter on methylmercury production in wetlands is an important environmental topic in Tibet, where is the province with the largest number of international rivers, including the Yarlung Tsangbo River. In this study, total mercury (THg) and methylmercury (MeHg) contents in soils from wetlands along the YTR were detected, and roles of the molecular composition of soil organic carbon (SOC) in the formation of MeHg were explained in detail by pyrolysis–gas chromatography/mass spectrometry technology (Py-GC/MS). On average, THg and MeHg contents were 62.9 ng/g and 5.88 ng/g, respectively. About 12.6% of total Hg was in the form of MeHg. Unexpected high methylmercury levels occurred in wetland soils along the YTR. The topsoils (0–20 cm) had more THg but less MeHg contents than those in subsoils (20–48 cm). The proportion of MeHg to THg (RHg) was higher in subsoils than in topsoils independent of wetland types. Correlations between THg, MeHg, and SOC were weak in topsoils but strong in subsoils. Lignin and phenol moieties of SOC pyrolysis products were significantly and positively related to THg in topsoils, while positive or negative correlations were found between THg, MeHg, and pyrolysis products of SOC in subsoils at p

The portable X-ray fluorescence spectrometry (pXRF) can be considered one of the most novelty for soil characterization. In tropical regions (e.g., Brazil), some studies have showed a consistent correlation between pXRF and laboratory-based methods. However, there is no any work dedicated exclusively for hydromorphic soils (gley or organic-rich soils). This study aims to assess the total elemental composition reported by portable X-ray fluorescence (pXRF) spectrometry and to compare it to laboratory-based wet digestion method and wavelength dispersive X-ray (WDXRF) spectrometry. A collection of 144 hydromorphic soil samples from six wetlands located in the Cerrado biome (Savannah), Brazil, was used for this investigation. Soil samples were disaggregated and passed through a 150- μ m nylon mesh and subjected to wet digestion (US EPA 3051a) followed by elemental determination via atomic absorption spectrometry (AAS). Subsamples of each ground soil were also directly analyzed via both pXRF and WDXRF. Linear regressions were performed to establish the relationship between methods. Several elements (Pb, Cu, Zn, Cr, Fe, Ti, Sr, and Y) determined via pXRF were successfully correlated to other methods (USEPA 3051a and WDXRF). Specially for Pb, a very strong correlation (R > 0.90) was observed between pXRF, WDXRF and US EPA 3051a methods. The pXRF revealed also to be a useful tool for characterization of hydromorphic soils and future studies can be conducted directly in the field to assess the elemental composition of Cerrado wetland soils.

NaCl and Na2SO4 are the foremost salt compositions in coastal wetlands, while their effects on soil net nitrogen mineralization still remain unclear. Aimed at investigating the two salt compositions on soil net nitrogen mineralization, a 30-day laboratory incubation experiment was respectively conducted by adding 5‰ NaCl and Na2SO4 to incubated coastal wetland soils under aerobic conditions. Our results showed that Na2SO4 addition increased the rates of mineralization (Rmin) by an average of 33.03% and nitrification (Rnit) by 23.84% during the incubation (p

Although bacteriophages are the most abundant biological entities on the planet, their genetic diversity, especially in natural wetlands, is poorly understood. In this study, the genetic diversity of cyanopodoviruses in sediments of two coastal wetlands in Northeast China was investigated by targeting the DNA polymerase (pol) gene. A total of 66 DNA pol clones were obtained. A BLAST search at the amino acid level showed that the obtained sequences had the highest identity ranged from 83 to 99% to the known sequences. A phylogenetic tree showed that the distribution patterns of DNA pol sequence were different between two wetland soils, and 29 clones of this study formed four wetland-specific groups, which suggested that unrevealed novel groups of cyanopodovirus inhabited in wetlands. In addition, nonmetric multidimensional scaling (NMDS) analysis of all DNA pol sequences from various environments showed that cyanopodovirus communities of coastal wetlands are in the intermediate position between marine water environments and terrestrial freshwater environments, which highlights that the coastal wetlands as transitional zones between inland freshwater environments and marine environments.

Most studies on electrogenic microorganisms have focused on the most abundant heterotrophs, while other microorganisms also commonly present in electrode microbial communities, such as Actinobacteria strains, have been overlooked. The novel Acidimicrobiaceae sp. strain A6 (Actinobacteria) is an iron-reducing bacterium that can colonize the surface of anodes in sediments and is linked to electrical current production, making it an electrode-reducing bacterium. Furthermore, A6 can carry out anaerobic ammonium oxidation coupled to iron reduction. Therefore, findings from this study open the possibility of using electrodes instead of iron as electron acceptors, as a means to promote A6 to treat NH4+-containing wastewater more efficiently. Altogether, this study expands our knowledge of electrogenic bacteria and opens the possibility of developing Feammox-based technologies coupled to bioelectric systems for the treatment of NH4+ and other contaminants in anoxic systems., Acidimicrobiaceae sp. strain A6 (A6), from the Actinobacteria phylum, was recently identified as a microorganism that can carry out anaerobic ammonium (NH4+) oxidation coupled to iron reduction, a process also known as Feammox. Being an iron-reducing bacterium, A6 was studied as a potential electrode-reducing bacterium that may transfer electrons extracellularly onto electrodes while gaining energy from NH4+ oxidation. Actinobacteria species have been overlooked as electrogenic bacteria, and the importance of lithoautotrophic iron reducers as electrode-reducing bacteria at anodes has not been addressed. By installing electrodes in the soil of a forested riparian wetland where A6 thrives, in soil columns in the laboratory, and in A6-bioaugmented constructed wetland (CW) mesocosms and by operating microbial electrolysis cells (MECs) with pure A6 culture, the characteristics and performances of this organism as an electrode-reducing bacterium candidate were investigated. In this study, we show that Acidimicrobiaceae sp. strain A6, a lithoautotrophic bacterium, is capable of colonizing electrodes under controlled conditions. In addition, A6 appears to be an electrode-reducing bacterium, since current production was boosted shortly after the CWs were seeded with enrichment A6 culture and current production was detected in MECs operated with pure A6, with the anode as the sole electron acceptor and NH4+ as the sole electron donor. IMPORTANCE Most studies on electrogenic microorganisms have focused on the most abundant heterotrophs, while other microorganisms also commonly present in electrode microbial communities, such as Actinobacteria strains, have been overlooked. The novel Acidimicrobiaceae sp. strain A6 (Actinobacteria) is an iron-reducing bacterium that can colonize the surface of anodes in sediments and is linked to electrical current production, making it an electrode-reducing bacterium. Furthermore, A6 can carry out anaerobic ammonium oxidation coupled to iron reduction. Therefore, findings from this study open the possibility of using electrodes instead of iron as electron acceptors, as a means to promote A6 to treat NH4+-containing wastewater more efficiently. Altogether, this study expands our knowledge of electrogenic bacteria and opens the possibility of developing Feammox-based technologies coupled to bioelectric systems for the treatment of NH4+ and other contaminants in anoxic systems.

Soil moisture is an important hydrological parameter, which is essential for a variety of applications, thereby extending to numerous disciplines. Currently, there are three methods of estimating soil moisture: ground-based (in-situ) measurements; remote sensing based methods and land surface models. In recent years, the cosmic ray probe (CRP), which is an in-situ technique, has been implemented in several countries across the globe. The CRP provides area-averaged soil moisture at an intermediate scale and thus bridges the gap between in-situ point measurements and global satellite-based soil moisture estimates. The aim of this study was to test the suitability of the CRP to provide spatial estimates of soil moisture. The CRP was set up and calibrated in Cathedral Peak Catchment VI. An in-situ soil moisture network consisting of time-domain reflectometry and Echo probes was created in Catchment VI, and was used to validate the CRP soil moisture estimates. Once calibrated, the CRP was found to provide spatial estimates of soil moisture, which correlated well with the in-situ soil moisture network data set and yielded an R2 value of 0.845. The use of the CRP for soil moisture monitoring provided reliable, accurate and continuous soil moisture estimates over the catchment area. The wealth of current and potential applications makes the CRP very appealing for scientists and engineers in various fields.Significance: The cosmic ray probe provides spatial estimates of surface soil moisture at an intermediate scale of 18 hectares. A single cosmic ray probe can replace a network of conventional in-situ instruments to provide reliable soil moisture estimates. The cosmic ray probe is capable of estimating soil moisture in previously problematic areas (saline soil, wetlands, rocky soil). Cosmic ray probes can provide data for hydro-meteorologists interested in land–atmosphere interactions. The cosmic ray probe estimates can be promising for remote sensing scientists for product calibration and validation.

Municipal biosolids in end-of-life lagoons can release phosphorus (P) to floodwater and contribute to P enrichment of receiving waters if the floodwater is released. Phosphorus release to floodwater is well-documented in agricultural and wetland soils, but information on flooding depth and timing effects on P release from flooded biosolids in end-of life municipal lagoons is currently lacking. This 42-day experiment utilized intact, cattail-(Typha latifolia L.) vegetated biosolids cores (45.7-cm diameter by 60-cm height) to investigate the effects of flooding depth (5, 15, and 25 cm) on P release from biosolids and on P fractionation in pore water, floodwater, and biosolids upon flooding of municipal biosolids. Averaged across flooding depths, TP rapidly increased from the onset of flooding (0.45 mg L−1) to day 14 (1.8 mg L−1) and remained relatively constant thereafter (1.8–1.9 mg L−1). Dissolved reactive P was the major fraction of P in pore water and floodwater. Flooding for more than 3 days resulted in the release of > 0.5 mg L−1 dissolved reactive P (DRP) to floodwater. Phosphorus release was positively correlated with Fe and Mn concentrations in pore water and with water-extractable inorganic P, labile inorganic P, and Fe/Al-bound organic P concentrations in biosolids. Results indicate that P release to floodwater; hence, risk to receiving water bodies, is minimal during the first 3 days of flooding. This suggests that release of floodwater from the lagoon presents minimal adverse impact to receiving surface waters if done during the early stages (

In the Tablas de Daimiel National Park (TDNP) wetlands, a semi-arid wetland system in Spain that is of international importance, it is believed that pollutants from a variety of sources accumulate. In the study reported here, we evaluated soils from the flooded part of this wetland in an effort to establish relationships between the abundance/structure of microbial communities (mainly cyanobacteria) and certain soil properties (redox potential, dissolved oxygen, organic matter, soil reaction, electrical conductivity, calcium carbonate, total nitrogen, soluble phosphorus and total phosphorus). This objective was achieved by establishing one transect from the entrance to exit of the flood plain, including sampling from potentially polluted sites. Substantial variations between sampling sites were found in soil in terms of salinity, dissolved oxygen (DO), organic matter (OM), total phosphorus (TP) and nitrogen (TN). The presence of primary producers was more evident in contaminated samples. In addition to calcium, high levels of oxidizable organic matter, traces of dissolved oxygen, and considerable amounts of nitrate and phosphates probably stimulated the growth of cyanobacteria, these latter characteristics can be explained as being due to the influence of wastewaters from urban, industrial and agricultural activities that run off directly into this unique wetland. In the future it will be necessary to understand the synergic effects of other soil properties., The authors are grateful to the Autonomous Organism Parques Naturales of Spain (OAPN) for providing financial assistance

In Eastern China, wetlands are common in the lower reaches of catchments or in coastal zones. Wetlands are at risk from eutrophication because of the large quantities of phosphorus (P) they receive from rivers. They are also decreasing in size. In this contribution, we present information about the composition of P in wetland soils, obtained using the Standards, Measurements, and Testing (SMT) protocol and 31P-nuclear magnetic resonance (NMR) spectroscopy. Average P concentrations varied in the different wetland soils and, in four of the five wetlands sampled, exceeded 500 mg∙kg−1. HCl-inorganic P (Pi) was the main Pi fraction in wetland soils. The percentage contribution of Pi (89.7 %) to total P was the highest in the Yangtze River estuary wetland. Six P components were detected by 31P-NMR analysis. Mono-P was the main organic P (Po) in wetland soils. Orthophosphate (Ortho-P) was positively and negatively related to NaOH-Pi (R 2 = 0.957, p

Hoe ziet een duurzaam en biodivers nat zandlandschap van de 21e eeuw eruit en hoe ontwikkelen we dat? Dat landschap zal ongetwijfeld een ander zijn dan dat van de 19e en de eerste helft van de 20e eeuw, maar de uitdaging is de totale soortenrijkdom hierin weer voldoende plaats te bieden. Dit artikel biedt een overzicht van de kennis die daartoe ontwikkeld moet worden.

Hoogvenen herbergen een unieke biodiversiteit, variërend van insectenetende zonnedauw, kleurrijke veenmossen tot broedende kraanvogels. Genoeg reden dus om hoogvenen te beschermen en te herstellen. Dankzij de nauwe samenwerking tussen beheerders en onderzoekers en de daaruit resulterende kennisontwikkeling is herstel van levend hoogveen in Nederland niet langer een droom. In dit artikel geven we een overzicht van de hoogtepunten van 18 jaar OBN-onderzoek en sluiten af met een kijkje naar de toekomst.