Dugansutton7809

In peri-urban areas, waste water is used to irrigate orchards due to scarcity of fresh water which increases heavy metals contents in soils, leaves and fruits. Due to excessive waste water irrigations, heavy metals enter into the food chain, which eventually causes metabolic disorders in humans. The present study was envisaged to investigate the effects of canal, tubewell and sewage water on the quality of mango fruits and heavy metals accumulation in soils, leaves and fruits. Leaf and fruit samples from an un-grafted (Desi mango) and six commercial cultivars of mango (Anwar Rataul, Aman Dusehri, Sufaid Chaunsa, Samar Bahisht Chaunsa, Kala Chaunsa and Anwar Rataul Late) grafted on Desi mango were collected from different mango orchards located in peri-urban areas of Multan (Pakistan) and analyzed for some physico-chemical attributes and heavy metals contents. Soil samples were also taken from these orchards irrigated with different water sources to assess the soils' heavy metals status. A significant variation was observed among the mango cultivars for their physico-chemical attributes. Sewage water irrigation improved total soluble solids (TSS), titratable acidity, ascorbic acid content, total phenolics, total carotenoids, total flavonoids and antioxidant activity of mango fruits. However, it did not affect fruit weight and shelf life. Among the heavy metals, copper and nickel contents were found in greater amounts in soils, leaves and fruits of sewage water irrigated orchards than canal and tubewell water irrigated ones. However, zinc and cadmium were not detected in any soil, water, leaf or fruit sample. The interaction among the sources of irrigation and the mango cultivars was significant for copper accumulation in different soil layers, copper and nickel accumulation in leaves of different mango cultivars, and fruit weight, titratable acidity, ascorbic acid content, total flavonoids and shelf life of mango fruits.A new method for algal community restructuring is proposed, where harmful algae growth is inhibited through the addition of remedial nano-agent, while probiotic algae growth is promoted or only affected indistinctively. In this paper, the inhibiting effects of five different nanomaterials on Microcystis aeruginosa (M. aeruginosa) and Cyclotella sp. were studied, and the optimal nanomaterial was served as algae-inhibition ingredient of the remedial agent. The effects of the remedial agent on algal growth and their physiological characteristics were investigated, and the restructuring of algal community in actual water samples was explored. The results indicated that the inhibition ratio of 10 mg/L nm-Cu2O/SiO2 on M. aeruginosa and Cyclotella sp. could reach 293.1% and 82.8% respectively, acting as the best candidate for algae-inhibiting ingredient. After adding the remedial nano-agent made with nm-Cu2O/SiO2, the content of chlorophyll a, protein, and polysaccharides of M. aeruginosa decreased sharply, while the physiological characteristics of Cyclotella sp. were not significantly affected. Besides, the total biomass and proportion of cyanobacteria dropped (P less then 0.05), but the Bacillariophyta biomass increased significantly (P less then 0.05). The uniformity index, Shannon-Wiener index, and richness index all increased significantly (P less then 0.05). Meanwhile, the quality of actual water samples has been improved evidently (P less then 0.001). Therefore, the prepared remedial nano-agent in this study can control the harmful algae bloom to a certain extent by restructuring the algal community in eutrophic water bodies.There is an increasing interest in introducing ecosystem services (ESs) and landscape ecological risk (LER) into environmental policies and governance. Yet, we know little about how to integrate LER into real decision-making and ESs management. Using the ESs valuation method and the models of InVEST and LER, this study analyzed the spatiotemporal changes of cropland food production, carbon storage, water yield, biodiversity index and LER of Bailongjiang watershed (BLJW), China in 1990, 2002 and 2014, and the relationship between them. We found clear spatial differences in both ESs and LER levels in BLJW during the study period. The cropland food production service kept rising, and the areas of high yield mainly distributed in the loessal regions of BLJW with intensive human population. The carbon storage, water yield and biodiversity index first decreased and then increased. check details The LER was higher in the areas along the valleys with low elevation and intensive human activities. The regional ecological zoning based on overlay analysis of ESs with LER is effective for providing interactive spatial knowledge for adaptive landscape management. Our results illustrate the integrative approach on linking landscape ecological risk with ecosystem services is a comprehensive and helpful methodology for both regional risk reduction and ecosystem services enhancement at landscape scale.Chemical pollution impinges on the quality of water systems and the ecosystem services (ESs) they provide. Expression of ESs in monetary units has become an essential tool for sustainable ecosystem management. However, the impact of chemical pollution on ESs is rarely quantified, and ES valuation often focuses on individual services without considering the total services provided by the ecosystem. The purpose of the study was to develop a stepwise approach to quantify the impact of sediment pollution on the total ES value provided by water systems. Thereby, we calculated the total ES value loss as a function of the multi-substance potentially affected fraction of species at the HC50 level (msPAF(HC50)). The function is a combination of relationships between, subsequently the msPAF(HC50), diversity, productivity and total ES value. Regardless of the inherent differences between terrestrial and aquatic ecosystems, an increase of diversity generally corresponded to an increase in productivity with curvilinear or linear effects. A positive correlation between productivity and total values of ESs of biomes was observed. The combined relationships showed that 1% msPAF(HC50) corresponded to on average 0.5% (0.05-1.40%) of total ES value loss. The ES loss due to polluted sediments in the Waal-Meuse river estuary (the Netherlands) and Flemish waterways (Belgium) was estimated to be 0.3-5 and 0.6-10 thousand 2007$/ha/yr, respectively. Our study presents a novel methodology to assess the impact of chemical exposure on diversity, productivity, and total value that ecosystems provide. With sufficient monitoring data, our generic methodology can be applied for any chemical and region of interest and help water managers make informed decisions on cost-effective measures to remedy pollution. Acknowledging that the ES loss estimates as a function of PAF(HC50) are crude, we explicitly discuss the uncertainties in each step for further development and application of the methodology.