Identifying climate change impacts on surface water supply in the southern Central Valley, California

Effect of jasmonic acid on the phytoremediation of dinitrophenol from wastewater by Solanum nigrum L. and Atriplex lentiformis (Torr.) S. Watson

Phytoremediation is one of the best methods for cleaning up natural resources like water because plants are eco-friendly and safe for the ecosystem. Hyperaccumulators, e.g., Solanum nigrum L. and Atriplex lentiformis (Torr.) S. Watson, have been used to remove toxic metals from soil and water through phytoremediation techniques, but it is unknown if they can remove hazardous chemicals such as dinitrophenol (DNP), from wastewater. A hydroponic experiment was conducted to study the efficiency of S. nigrum and A. lentiformis in removing DNP from wastewater. Jasmonic acid (JAC) was applied to the tested plants in two doses, 0.25 and 0.50 mmol, in an effort to better understand how it affects phytoremediation effectiveness. The growth of S. nigrum and A. lentiformis improved significantly (p < 0.05) by the foliar application of JAC. The applications of JAC1 and JAC2 significantly (p < 0.05) increased nutrient uptake and chlorophyll concentrations in S. nigrum and A. lentiformis plants. The foliar spraying of S. nigrum and A. lentiformis with JAC significantly (p < 0.05) increased the antioxidant enzymes activity, i.e., SOD and POD. The levels of osmoregulatory substances like proline and carbohydrates significantly (p < 0.05) increased after JAC was sprayed on S. nigrum and A. lentiformis plants. In the case of S. nigrum, the efficiency of DNP removal varied between 53 and 69%, with an average of 63%, while in the case of A. lentiformis, it varied between 47 and 62%, with an average of 56%. The removal efficiency of DNP reached 67 and 69% when S. nigrum was sprayed with JAC1 and JAC2. When JAC1 and JAC2 were sprayed on A. lentiformis, DNP removal efficiency rose from 47 to 60 and from 47 to 62%, respectively. S. nigrum and A. lentiformis plants can be grown normally and survive in dinitrophenol-contaminated water without showing any toxic symptoms. S. nigrum and A. lentiformis have a powerful antioxidant system and the ability to produce vital compounds that alleviate the stress caused by DNP toxicity. The findings are crucial for cleaning up polluted water and protecting the ecosystem's health from dangerous pollutants.

Curbing land degradation and mitigating climate change in mountainous regions: a systemic review

Human population is envisaged to continue to grow, with a tremendous contribution to land degradation and climate change. Climate change and land degradation are intertwined, thus tackling climate change means mitigating land degradation. Climate change is a worldwide problem that affects lives and livelihoods; henceforth, mitigating measures are urgently required. With their unique, rich biodiversity, mountain areas are severely sensitive to climate change and land degradation; therefore, a speedy need to curb land degradation in mountain areas is needed. The aim of this systematic review was to appraise different strategic methods used globally to minimise land degradation and sustain mountainous areas in a frequently changing climate. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was utilised in this systematic review. The Scopus data base was utilised for document search, with a selection of articles limited between the years 2012 and 2021. Only articles written in English were considered. After assessing the abstracts, 703 articles were retained for a full review, leading to the final selection of 84 articles. The results show that soil erosion, overgrazing and construction of infrastructure are major causes of land degradation. The human population increase is also an enormous contributing factor to activities leading to land degradation and climate change. A conspicuous intensification of agricultural activities is expected to continue due to rising food demand. Curbing land degradation and climate change in mountain areas can be enforced by the government through stricter regulations. However, regulations and policies must be locally initiated, instead of globally initiated, with local communities being the main stakeholders. Hence, bottom-up rather than top-down policies would encourage local communities to embrace mitigation policy initiatives.

Iodine adsorption isotherms on Matamba fruit shell stemmed biochar for wastewater re-use strategy in rural areas owing to climate change

Remote communities in developing countries are facing ever-increasing water scarcities, due to cumulative demand induced by the climate change and global warming impacts. For the socio-economic and health well-being of the local communities, sufficient, efficient, and affordable water supply is fundamental from local-based adsorbents. Matamba Fruit shell was obtained and pyrolyzed to obtain well-transformed biochar, which exhibited enough capacity to remove Iodine from aqueous solution. The maximum capacity of adsorption of the Matamba Fruit shell was 2.122 mmol L^-1 and 2.12 mmol L^-1 from conventional and Bayesian statistics correspondingly. The difference was insignificant. The surface morphology was evaluated by the Field Emission Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (FESEM-EDX) which revealed porous structures with irregular openings enough to purge wastewater pollutants. The material surface area was 267.0 m² g^-1, as estimated by both approaches, making the Matamba Fruit shell an emerging potential candidate for environmental pollution control and use in bioremediation practices. The Fourier-transform infrared spectroscopy (FTIR) revealed that surface functional groups of Matamba Fruit shell biochar have enough peak variations in intensity and position due to vibration variations of the surface. The Fruit shell has different functional groups including the hydroxyl (-OH) and the carbonyl groups (CO), CC stretches of aromatic rings, and the carboxylate (C-O-O-) groups. The biochar understudy unveiled its capability for wastewater-treatment reuse in local and urban communities of developing countries to safeguard their health and access to water-supply as the climate change reverberations are affecting the developing countries more pronounced than before.

Enhancing Soil and Water Assessment Tool Snow Prediction Reliability with Remote-Sensing-Based Snow Water Equivalent Reconstruction Product for Upland Watersheds in a Multi-Objective Calibration Process

Precipitation occurs in two basic forms defined as liquid state and solid state. Different from rain-fed watershed, modeling snow processes is of vital importance in snow-dominated watersheds. The seasonal snowpack is a natural water reservoir, which stores snow water in winter and releases it in spring and summer. The warmer climate in recent decades has led to earlier snowmelt, a decline in snowpack, and change in the seasonality of river flows. The Soil and Water Assessment Tool (SWAT) could be applied in the snow-influenced watershed because of its ability to simultaneously predict the streamflow generated from rainfall and from the melting of snow. The choice of parameters, reference data, and calibration strategy could significantly affect the SWAT model calibration outcome and further affect the prediction accuracy. In this study, SWAT models are implemented in four upland watersheds in the Tulare Lake Basin (TLB) located across the Southern Sierra Nevada Mountains. Three calibration scenarios considering different calibration parameters and reference datasets are applied to investigate the impact of the Parallel Energy Balance Model (ParBal) snow reconstruction data and snow parameters on the streamflow and snow water-equivalent (SWE) prediction accuracy. In addition, the watershed parameters and lapse rate parameters-led equifinality is also evaluated. The results indicate that calibration of the SWAT model with respect to both streamflow and SWE reference data could improve the model SWE prediction reliability in general. Comparatively, the streamflow predictions are not significantly affected by differently lumped calibration schemes. The default snow parameter values capture the extreme high flows better than the other two calibration scenarios, whereas there is no remarkable difference among the three calibration schemes for capturing the extreme low flows. The watershed and lapse rate parameters-induced equifinality affects the flow prediction more (Nash-Sutcliffe Efficiency (NSE) varies between 0.2–0.3) than the SWE prediction (NSE varies less than 0.1). This study points out the remote-sensing-based SWE reconstruction product as a promising alternative choice for model calibration in ungauged snow-influenced watersheds. The streamflow-reconstructed SWE bi-objective calibrated model could improve the prediction reliability of surface water supply change for the downstream agricultural region under the changing climate.