Watershed Ecology and the Environment最新文献

Urbanization has expanded rapidly worldwide in recent decades, and has led to a series of environmental changes. With the improvement of the urban habitat, the density of wildlife is on the rise, especially for the birds. However, birds are host to a variety of viruses, pathogenic microorganisms and parasites, and the increase of their density may amplify the risk of disease transmission in cities. Thus, understanding the characteristics of regional bird community aids the integration of knowledge about the risk of disease transmission by birds. Here, we conducted a field survey in summer, 2021, to compare the differences in vegetation, species richness and individual numbers of bird in Shanghai urban and surrounding areas covering 28 zones along an urbanization gradient and to assess the possibility of bird transmission risk in Shanghai. We recorded 122 plant species and 3416 bird individuals of 23 species. Our results found that urbanization has led to a decline in bird species and densities than relatively pristine habitats (rural, agroforestry habitat, urban park), and based on our literature collection, most species carrying avian influenza virus were migratory waterbirds (anatidae and shorebird) that relatively away from urban area. Our study suggests that urbanization reduces bird diversity, but urban birds may have a low probability of transmitting the avian influenza virus to humans.

Emerging chemical substances have dramatically increased in aquatic ecosystems throughout the last few decades and are creating harmful effects on sustainable environments. Herbicides and antibiotics are usually consumed simultaneously and liquidated into the aquatic system as effluents. Due to the dearth of rigorous control of emerging substances, it poses a threat to ecotoxicologists and limnologists because of their hidden roles against non-target aquatic organisms like zooplankton. These substances have a negative impact on grazer inducers and disrupt community-level zooplankton-phytoplankton relationships. But the hidden role of these phenomena due to these substances is still clearly unknown. So, the present mesocosm study summarises and updates the current status of antibiotics and herbicides on the survival of zooplankton species. We also discuss the role of various herbicides and antibiotics on these non-targeted organisms and create baseline information to overcome the above-mentioned risks and expand the scope of future research in this field.

In the present study, hydrophilic silica aerogel (HPSA) was synthesized by ambient pressure drying method and was successfully used as an adsorbent for the removal of Cationic dyes (Crystal violet- CV) from the aqueous solution. The synthesized sample was characterized and examined by Fourier transform infrared spectroscopy (FTIR), Bruner – Emmett – Teller (BET), x-ray diffraction (XRD), Zeta potential pH _zp, Nuclear Magnetic Resonance Spectrometer (NMR), and Scanning Electron microscope (SEM). The effect of different parameters such as pH, initial concentration of dyes, contact time, temperature, and their effect on the removal of CV dyes was studied. Silica aerogel synthesized was excellent and 96 % removal of CV dyes on the optimum value of the parameters of 30 min contact time, 303 K temp, 7 pH, 50 mg/l Conc., 0.3 g/l dose of HPSA was obtained. Langmuir, Freundlich, Temkin,and D-R models were applied in the equilibrium studies and obtained the maximum adsorption capacity 137.17 mg/g. pseudo-first, second-order, and intraparticle diffusion models were employed to indicate the chemisorption behavior in the kinetic study on the adsorption. Thermodynamic parameters showed the adsorption process as Exothermic and spontaneous. Sticking Probability (S*≪1) indicated HPSA as a good adsorbent for the removal of dyes. HPSA has demonstrated the potential for regeneration while affirming its remarkable removal efficiency, Cost effectiveness and Environmental compatibility.

Taipu River is one of the important river channels of Taihu Lake, and also an important water body in the demonstration zone of green and integrated ecological development of the Yangtze River Delta. In this study, we collect the water quality monitoring data of Taipu River and related research results of Taipu River water quality, and analyze the water environment characteristics of Taipu River by analyzing the water quality status of Taipu River main stream and East Taihu Lake. The results indicate that from 2016 to 2018, the annual mean values of conventional indexes in main sections of the Taipu River main stream were maintained in Class II to III. The incoming water from the Taipu River mainly includes the East Taihu Lake and its tributaries. The water quality of the East Taihu Lake is superior to that of the Taipu River. The water quality of the Jinze section is mainly affected by the inflow from the East Taihu Lake. Increase the discharge under Taipu sluice to supply high-quality water, which can effectively guarantee the water quality of the section. Then we identify the main water environmental problems in Taipu River basin. The results of our analysis can provide support for the water ecological environment protection of Taipu River.

It is vital to employ efficient methods to calculate and determine the threshold of river ecological flow. These methods help to get the river ecological status control countermeasures in the plain river networks and construct a flawless long-term mechanism of ecological flow control (water level). According to the river's current environment and the actual circumstances surrounding its operation and administration, the upper, middle, and lower reaches make up the three sections of the Zong-Liutang River in the Plain of Northern Jiangsu. Furthermore, the ecological water level governing factor for each reach was analyzed and studied. The ecological water level threshold in the upper and lower reaches of the Zong-Liutang River adopted the specified values of Jiangsu Provincial Department of water resources. The threshold of the middle reach was thoroughly analyzed by using the determination method with multi-criteria, which consisted of the hydrological and hydraulic methods (including yearly minimum water level with a 90% assured rate method; wetted perimeter method; minimum monthly average water level method), aquatic living conditions method, and river landscape entertainment factor method. Taking into account the hydrological and hydrodynamic characteristics, observed hydrological data conditions of rivers, and the actual operation rules of rivers and water projects regulations in the Northern Jiangsu plain. Through comparing and contrasting actual operation and management plans, the target values of the ecological water level for the river's upper, middle, and lower reaches were 17.4 m, 8.96 m, and 7.5 m, respectively. Based on the river's ecological water level's control value, which was found through a thorough analysis, and the river's real operation and management conditions, specific measures to protect the river's ecological water level were suggested. These included developing a perfect and workable ecological flow control method, speeding up the development of an ecological water level goal assurance early warning system, and an ecological flow and inlet system.

Ecological health of two waterbodies i.e., cistern-made and ‘natural’ earthen-made waterbody was compared in the present study based on temporal variations of physicochemical and biological parameters. Number of physicochemical parameters [transparency, temperature, pH, electrical conductivity (EC), total dissolved solids (TDS), total suspended solids (TSS), dissolved oxygen (DO), total hardness (TH), total alkalinity (TA), biochemical oxygen demands (BOD), nitrate, phosphate and chlorophyll a (Chl a)], and biological parameters, e.g., zooplankton community and aquatic macrophytes were studied seasonally. Zooplankton communitiy comprised six arthropods and two rotifers. SIMPER analysis depicted that Moina sp., Daphnia sp., and Cyclops sp. were dominant species in cistern pond while Cyclops sp., Daphnia sp., Keratella sp. and Brachionus sp. were dominant in earthen natural pond. Abundance of species was highest in summer followed by post-rainy and winter in both the ponds while maximum abundance of zooplankton was recorded in summer. Species richness peaked in winter in natural pond, while in cistern pond species richness and diversity raised in summer. Multivariate analyses depicted significant temporal variation in zooplankton species in both the conditions. RELATE analysis revealed that temporal variation in species distribution and zooplankton community was significantly correlated with environmental parameters. Moreover, biological-environmental best matching (BIO-ENV) analyses indicated that water temperature, pH, TH and BOD (for cistern pond) and water temperature, EC and TSS (for earthen natural pond) were the main driving forces for temporal variations in species distribution and zooplankton community. Additionally, correlation analysis depicted that Moina sp., Daphnia sp., Diaptomus sp., Cyclops sp., Cypris sp., Bosmina sp., and species abundance was positively (significant) correlated with transparency, water temperature, and Chl a in natural pond. On the other hand, correlation analysis depicted that zooplankton species, species abundance, evenness and diversity were positively correlated with water temperature, DO, BOD and Chl a in cistern pond. Moreover, abundance of aquatic macrophytes were limited in three basic groups, namely free floating [(Lemna sp. (Major), Lemna sp. (Minor), Azolla sp., Pistia sp. and Eichhornia sp.], rooted submerged [Hydrilla sp., Ceratophyllum sp.] and rooted emerged [Nymphaes sp. and Ipomoea sp.]. Further, trophic state index (TSI) value revealed that both the ponds are hyper-eutrophic (‘natural’ waterbody > cistern waterbody) with a strong temporal variations. Therefore, these data could be used as water quality community-based bio-assessment tool as well as basis of water