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Bendixen posted an update 7 months, 1 week ago
Sulfate (SO42-) affects the cycling of ecologically important substances, such as carbon, nutrients and metals, but the contribution of anthropogenic activities in sulfate load entering aquatic systems is poorly known. We calculate specific sulfate loads for land cover types, atmospheric deposition and point sources, and then estimate the source-specific flux of sulfate to Finnish surface waters. The largest sulfate flux, entering mostly the Baltic Sea, originates from agricultural fields on acid sulfate soil (24% of total flux). Forests on mineral soil, which cover 67% of the country’s surface area, form the second largest source (21%). Additionally, agricultural fields on non-acid soil cause noticeable sulfate flux (16%). Pulp and paper mills were the key point sources (20%) for sulfate. We find that anthropogenic activities contribute to elevated sulfate levels in waters potentially affecting the cycling of nutrients, metals and formation of greenhouse gases in naturally sulfate-poor freshwaters. selleck compound Based on these findings, sulfate should be systematically included in monitoring and pollution control measures.Mangrove ecosystems are essential to society, providing ecological and economic services, and play a crucial role in the geochemical land-ocean interface as a sink for potentially toxic metals. This study assessed metals (Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sr and Zn) and arsenic in sediments from three mangrove zones (Tidal Flat, Rhizophora mangle L. and Avicennia schaueriana Stapf & Leechman ex Moldenke forests) during two seasons spring of 2015 and autumn of 2016, with the latter being a severe drought year. Overall results suggest that Fe/Mn oxyhydroxides and clay minerals control the distribution of metal and arsenic in the Tidal Flat zone. In the mangrove forest however, sulfur and organic matter dominate complexation, with Fe mainly present as insoluble sulfide, and As, Cd, Cu and Zn as metal sulfides or organometallic complexes. In the autumn of 2016, all elements except Cd and Pb had lower concentrations compared to the spring of 2015. Cd and Pb were probably transferred from sources other than mangrove sediments, due to increased saline water intrusion, a consequence of reduced riverine flow, and precipitated in the Rhizophora mangle and Avicennia schaueriana mangrove forests. This increase of Cd and Pb in the mangrove forest suggests potential storage of metal contaminants in the organic rich areas, a change in availability and potential toxicity to fauna and flora and a need for regulatory responses to sediment quality. These results indicate a change in sediment metal contaminant dynamics with the increasing occurrence of extreme weather events – an increased risk to the ecosystem.Extensive, progressive rock emergence causes localized variations in soil biogeochemical and microbial properties that may influence the capacity for the regeneration of degraded karst ecosystems. It is likely that karst ecosystem recovery relies on the persistence of soil functions at the microbial scale, and we aimed to explored the role of interactions between soil bacterial taxa and identify keystone species that deliver key biogeochemical functions, i.e. carbon (C) and nutrient (nitrogen, N and phosphorus, P) cycling. We applied high-throughput sequencing and phylogenetic molecular ecological network approaches to topsoils sampled at rock-soil interfaces and adjacent bulk soil along an established gradient of land-use intensity in the Chinese Karst Critical Zone Observatory. Bacterial α-diversity was greater under increased perturbation and at the rock-soil interface compared to bulk soils under intensive cultivation. However, bacterial ecological networks were less intricate and connected fewer keystonein keystone taxa in this microenvironment. Our study provides foundations to test the success of different regeneration practices in restoring soil microbial diversity and the multifunctionality of karst ecosystems.Phytoremediation coupled with agro-production is a sustainable strategy for remediation of toxic metal contaminated farmlands without interrupting crop production. In this study, high accumulating oilseed rape was rotated with low accumulating rice to evaluate the effects of crop rotation on growth performance and uptake of cadmium (Cd) in plants. In this system, oilseed rape was inoculated with plant growth promoting endophyte (PGPE) consortium, and rice was applied with soil composite amendment and foliar inhibitor. The results showed, compared with rice monoculture, crop rotation coupled with superposition measure has potential to enhance yield, biomass and nutritional quality of both crops, as well as to increase Cd uptake in non-edible tissues of oilseed rape and to reduce Cd concentration in individual parts of rice, thus accelerating phytoextraction and ensuring food safety. These comprehensive management practices removed 7.03 and 7.91% total Cd from two experiment fields, respectively, in three years phytoremediation. These results demonstrated a feasible technical mode for phytoremediation coupled with argo-production in slightly Cd contaminated field, and also provided useful information for further investigation of interaction mechanisms between the rotated crops and biofortification measures.Hydrophobic environmental chemicals bio-accumulate in adipose tissue (AT) in animals and humans, but their impact on diseases related to adipose tissue dysfunction remains unclear. Moreover, visceral rather than subcutaneous (SC) fat deposition is more closely associated with cardio-metabolic diseases such as type 2 diabetes, fatty liver and cardiovascular diseases. We therefore tested the hypotheses that environmental chemicals bio-accumulate in a fat depot specific pattern and that these patterns are related AT inflammation and obesity comorbidities. First, we developed an extraction method for detecting and quantifying a set of 9 persistent organic pollutants (POPs) in human AT. The quantified chemicals exhibit KOW coefficients from 4 to 7. Paired abdominal omental and SC AT samples were obtained from 54 individuals (30 women, 24 men) with a wide range of body mass index (BMI, 16-70 kg/m2) during laparoscopic abdominal surgeries. Among the POPs are classical halogenated substances like Dichlorodiphenyldichloroethylene (DDE) and polychlorinated biphenyls (PCBs), but also fragrance substances.