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1.
Environment, Development and Sustainability - Economic, environmental, and social imperatives make sustainability-oriented entrepreneurship an indispensable phenomenon of the day, yet only sparse...  相似文献   
2.
Assessing mitigation of phosphorus (P) leaching from subsurface drainage systems is challenging due to high spatial and temporal variation in leaching. Mean measured total P leaching from a clayey soil in an eight-year study period (four replicates per treatment) was (kg ha?1 year?1): 1.21 from shallow autumn tillage (ShT), 0.84 from unfertilised fallow (UF), 0.81 from conventional autumn ploughing (CT) and 0.57 from structure liming (SL–CT). Treatment was not significant using Richards–Baker flow index or a distance factor as covariate (p = 0.084 and 0.057). A tendency for lower leaching was obtained comparing SL-CT with ShT (p adjusted = 0.060 and 0.009 respectively). A combination of measures adapted to drainage conditions and clay content in different parts of the field is proposed since P leaching was approximately halved from an adjacent field (4.3 ha) in a three-year post-period compared with a three-year pre-period for structure liming the entire field and drainage system renovation plus structure lime drain backfilling.  相似文献   
3.
Environmental Science and Pollution Research - Medicines and drugs consumption by all populations of the world can be expected to result in the contamination of the environment since 30–90%...  相似文献   
4.
Environmental Science and Pollution Research - Coronavirus refers to a group of widespread viruses. The name refers to the specific morphology of these viruses because their spikes look like a...  相似文献   
5.
Environmental Chemistry Letters - Pesticides contribute to human welfare by reducing vector-borne diseases and protecting crops against pests. Insecticides are the most widely employed pesticides...  相似文献   
6.
ABSTRACT

The present research aimed to determine the lowest levels of three heavy metals (Pb, Cd and Cu) to which the larvae of Southern House Mosquito, Culex quinquefasciatus are susceptible in water. The study also aimed to investigate the effects of these heavy metals on the development of Cx. quinquefasciatus at concentrations set by Pakistan Environmental Protection Agency (Pak-EPA) as permissible levels for liquid industrial effluents. The 2nd instar larvae of Cx. quinquefasciatus were exposed to different concentrations of Pb, Cd and Cu and their effects on oviposition preference, egg hatching rate and larval development were studied. The LC50 values of Pb, Cd and Cu were 12.6, 6.3 and 2.6?ppm, respectively. Gravid female mosquito adults deposited a significantly lower number of egg rafts in containers containing 0.50?ppm Pb or 1.0?ppm Cu in water. Each of the heavy metals in water resulted in significantly (p?<?0.05) lower egg hatching rate, prolonged time to pupation, lower pupation rate, prolonged time to adult emergence, lower adult emergence rate and higher female to male ratio. It is concluded that the 2nd instar larvae of Cx. quinquefasciatus are susceptible to Pak-EPA permissible levels of Pb, Cd and Cu in municipal and liquid industrial effluents.  相似文献   
7.
Environmental Science and Pollution Research - Cadmium is an important widely distributed heavy metal in the environment due to its several industrial uses, while milk thistle is an important herb...  相似文献   
8.
Long-term median total phosphorus (TotP) and total nitrogen (TotN) concentrations were 0.08 and 5.5 P/N (mg L-1), respectively, in 10 agricultural streams monitored since 1988 in Sweden. The areas ofthe respective catchments are 2–20 km2. The period 1992/2002 was characterised by stable hydrological conditions without any flow trends in nearly all of the streams. The highest average TotP concentration, 0.17 mg P L-1, was found in a small agriculturalstream in the largest Swedish agricultural plain. The soil texture is here characterised by a large specific surface area of the soil particles, and the agriculture by cereal production. The second highestaverage TotP concentration, 0.14 mg P L -1, was measured in the surface water from a catchment characterised partly by clay soils andby production of potato, spring cereals and grass. This catchment had twice as many fields with a calculated high risk for P losses comparedwith another monitored catchment in the same watershed (River Rönneå). There was a significant downward TotP trend during 1992/2002 of 0.0012 mg P L-1 yr-1 (Sen's slope estimator) in the catchment where many fields risk P losses and which had a reduced P manure application rate of –20% during 1995/2000. In recent years practically no manure has been spread during autumn. Bypass flow of nitrate through one soil has been suggested to influence the LOWESS (LOcally WEighted Scatterplot Smothing) fitting curve of TotN. Total nitrogen concentration decreased in most of the catchment. The average downward slope was similar to a general TotN reduction of 0.069 mg N L-1 yr-1. During the period 1992/2002 this was equal to slightly more than 10 per cent. Cultivation of catch crops wasrelatively uncommon until 2002, but this practice is expected to expandto larger areas during 2003 and in the future.  相似文献   
9.
The concentrations of Zn, Cu, Cd, and Pb were determined in different tissues of mudskipper fishes Periophthalmodon schlosseri caught at two selected locations (Morib and Remis) of the intertidal mudflat area of Selangor state, West Coast of Peninsular Malaysia and in surface sediment samples. Metal concentrations in the mudskipper tissue and in the sediment samples tended to vary significantly (p < 0.05) between the two locations. Higher metal concentrations (except for Zn) were mostly found in the tissues of mudskippers from Remis. For sediment samples, significantly (p < 0.05) higher metal concentrations of all metals were also found at Remis. Generally, metal distribution between different tissues of mudskipper varied with scales being highly accumulative of Zn, Cd, and Pb, while for Cu, the highest mean concentrations were found in the liver. The lowest mean concentrations of Zn, Cu, and Cd were found in the muscles except for Pb, which was lowest in the liver. This study suggests that mudskippers can be potential biomonitoring organisms for heavy metal bioavailability and contamination of intertidal coastal mudflats. The concentrations of Cd and Pb were slightly above the acceptable limits of Malaysian and European food safety guidelines.  相似文献   
10.
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