The forest nitrate cycle is a crucial part of the watershed nitrate load but has received limited attention compared to that of agricultural and residential land. Here, we analyzed the status and sources of riverine nitrate fluxes and identified the characteristics and contribution of forest nitrate loss to the riverine system in a mid-high latitude forested watershed using monthly field sampling and a modified Soil and Water Assessment Tool (SWAT) with enhanced forest nutrient cycle representation. The results indicate that nitrate losses in the headwater stream and downstream exhibit different seasonal characteristics.
View Article and Find Full Text PDFAntibiotics have gained increasing attention as pharmaceuticals widely existing in human society. Under low temperature conditions, antibiotics tend to have higher environmental persistence, which poses a potential threat to ecological environment, but research on antibiotics in low-temperature basins is still lacking. Therefore, for investigating occurrence, spatio-temporal distributions, and ecological risks of antibiotics in a seasonal freeze-thaw basin, rivers in Tumen River basin were selected and sampled, including 25 samples during the river-freezing season and 27 samples during the non-freezing season.
View Article and Find Full Text PDFVanadium, like many trace metals, is persistent and detrimental to ecosystems at elevated concentrations. Likewise, it is versatile, functional, and used in many industries. Jiaozhou Bay (JZB) and Laizhou Bay (LZB) are valuable coastal ecosystems in China coexisting with several of these vanadium-related industries; however, limited studies have been conducted regarding vanadium occurrence, distribution, sources and risks in sediments.
View Article and Find Full Text PDFThe leaf litter decomposition is the important chain for the nutrient cycle in forest ecosystem, but its degradation dynamics and pulse discharge patterns in freeze-thawing watershed needed complete understanding. By integrating field observations and MODIS data, the temporal-spatial distributions of snow coverage and forest leaf litter biomass were analyzed. The critical period for snowmelt runoff under warming temperature and the relatively slow degradation patterns were identified.
View Article and Find Full Text PDFVariations in litter decomposition and nutrient migration are constraints to accurately estimate watershed diffuse forest pollution under the combined effects of topographic heterogeneity and climate change. In this study, remote sensing data, decomposition and leaching experiments, and the Soil and Water Assessment Tool (SWAT) were used to quantify the release, export, and transport characteristics of diffuse nutrients from forest litter under two climate scenarios (the current climate condition [S1] and the future warming and drying climate condition [S2]), and the impacts on aquatic environment were identified. The annual litter decomposition was 27.
View Article and Find Full Text PDFNutrients exported from forest litterfall significantly contribute to the global cycling of elements and the water quality in watersheds. Simulating the watershed discharge load is challenging because of the combined effects of the decomposing litterfall and topographic heterogeneity. We quantified the contribution of diffuse nutrient export from forest litterfall in a low temperature watershed using artificial rainfall experiments and watershed territorial modeling with remote sensing data, and therefore, the critical spatial factors and corresponding nutrient export dynamics were identified.
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