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g of the eco-friendly processes discussed in the penultimate section and their optimization for possible integration into the RO plants.The growing incidence of microcystins (MCs) in the environment has become an issue of global concern for the high ecological and human health risks. Herein, a comparative adsorption of three MCs (MC-LR, MC-YR and MC-RR) by spent mushroom substrate (SMS)-derived biochars from contrasting pyrolytic conditions (temperature 600/300 °C; and gas steam CO2/N2) was surveyed to better understand the mechanisms and factors affecting the adsorption performance. For biochar preparation, 600 °C and CO2 led to greater levels of aromaticity, ash, SBET, and porosity, while 300 °C and N2 created more surface functional groups. The adsorption of MCs by biochars was a pH-dependent and endothermic physisorption process, following the pseudo-second-order kinetics (R2 = 0.99) and linear isotherm model (R2 &gt; 0.88). The distribution coefficients Kd (0.98-19.2 L/kg) varied greatly among MCs (MC-YR &gt; MC-RR &gt; MC-LR) and biochars (BC600 &gt; BN600 &gt; BC300 &gt; BN300), which depends on the combined effects of hydrophobicity, electrostatic attraction, H-bonding, cation bridging, and the amounts of adsorption sites on biochars. Higher ash, SBET, and total pore volume of BC600 facilitated the adsorption capacity for MCs relative to other biochars. Furthermore, the co-adsorption efficacy for MCs (Kd = 1.09-8.86 L/kg) was far below those for the single adsorption, indicating strong conflicts among competing MCs. This study sheds light on the roles of pyrolytic temperature and gas steam in biochar properties, and elucidates the mechanisms and factors affecting the adsorption performance of different MCs, which lays a foundation for MCs removal from water.To further understand the underlying mechanisms involved in the developmental toxicity of crude oil and chemically dispersed crude oil on fish early-life stages (ELS), zebrafish (Danio rerio) embryos were exposed to GM-2 chemical dispersant (DISP), low-energy water-accommodated fractions (LEWAF), and chemically enhanced WAF (CEWAF) of Merey crude oil at sublethal concentrations for 120 h. We employed the General Morphology Score (GMS) and General Teratogenic Score (GTS) systems in conjunction with high-throughput RNA-Seq analysis to evaluate the phenotypic and transcriptomic responses in zebrafish ELS. Results showed that ΣPAHs concentrations in LEWAF and CEWAF solutions were 507.63 ± 80.95 ng·L-1 and 4039.51 ± 241.26 ng·L-1, respectively. The GMS and GTS values indicated that CEWAF exposure caused more severe developmental delay and higher frequencies of teratogenic effects than LEWAF exposure. Moreover, no significant change in heart rate was observed in LEWAF treatment, while CEWAF exposure caused a signifsights into the effects of crude oil and chemical dispersant on fish ELS.Drought is a complex natural hazard that affects ecosystems and society in several ways and it is important to quantify drought at the river basin scale. Assessment of drought requires both hydrological observations and simulation models as the data are generally scarce. Therefore, we use remote sensing products to help understand drought conditions in four basins in South India. This study analysed the correlation among five drought indices for four seasons gravity recovery and climate experiment - drought severity index (GRACE-DSI), standardized precipitation index (SPI), self-calibrated palmer drought severity index (sc_PDSI), standardized precipitation-evapotranspiration index (SPEI), and combined climatologic deviation index (CCDI) with GRACE terrestrial water storage anomalies (TWSA) using the Pearson correlation coefficient (r) from 2002 to 2016 over the Godavari, Krishna, Pennar, and Cauvery river basins. Basin scale drought events are evaluated using CCDI, GRACEDSI, sc_PDSI, SPI12, and SPEI12 at seasonal and monthly time scale. Characteristics of drought event analysis are calculated for CCDI monthly. The results showed that GRACE TWS is highly correlated with GRACE-DSI, CCDI, and sc_PDSI. Seasonally, high spatial correlations between CCDI and GRACE-DSI with GRACE TWS are evident for all the river basins. Additionally, correlation is found to exist between sc_PDSI and GRACE TWS as soil moisture content is an operating variable between them. The 12-month SPI and SPEI correlated better with GRACE TWS than the 3 and 6-month periods. Among the four basins, droughts in the Krishna Basin lasted 29 months, longer than in the rest of the basins between 2003 and 2005. Overall, CCDI and GRACE-DSI indices are found to be effective for examining and evaluating the drought conditions at the basin scale.Plants are vital components of the nitrogen (N) cycling in the riparian zones. Understanding of N uptake strategies of riparian plants, including N sources and preference in N forms (ammonium (NH4+) vs. nitrate (NO3-)), is essential to advance our knowledge on the role that plants play in regulating nutrient biogeochemical cyclings in the riparian areas. In this study, stable N isotopes (δ15N) of three riparian plants, including Acorus calamus, Canna indica and Phragmites australis, and the δ15N of NH4+ and NO3- in different sources were measured during the plant growing season (June-September) in the Taihu Lake Basin. The dissolved inorganic N (DIN) from river water, groundwater, rainwater and soil were considered as the major N sources for plants in the riparian ecosystem. [https://www.selleckchem.com/products/baxdrostat.html Baxdrostat mouse] Our results indicated that soil was the largest source for plant N nutrition, with significantly different (P less then 0.05) contributions from soil observed among plant species (80.5 ± 4.1, 73.9 ± 2.8 and 58.7 ± 6.1% for A. calamus, C. indica, and P. australis, respectively). Meanwhile, complex water networks, shallow water tables, and high DIN content in rainwater lead to nonignorable N contributions from river water, groundwater and rainwater to plants. Groundwater contributed more percentage of N to P. australis (12.8 ± 3.2%) than A. calamus (6.1 ± 1.9%) and C. indica (8.0 ± 1.5%), which is likely attributed to the deeper roots of P. australis. All plants showed similar N preference for NO3- during the growing season. External environmental conditions and plant characteristics and adaption to more abundant soil NO3- content are possible explanations. Our research could provide important information for vegetation selections during the process of riparian ecological restoration. Reasonable choice of vegetation is essential to plant growth and water quality management, especially in agricultural watersheds where N concentrations are relatively high in agricultural runoff due to the wide uses of N fertilizers.