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1.
Pollution and Capital Markets in Developing Countries   总被引:3,自引:0,他引:3  
It is said that firms in developing countries do not have incentives to invest in pollution control because of weak implementation of environmental regulations. This argument assumes that the regulator is the only agent that can create incentives for pollution control, and ignores that capital markets, if properly informed, may provide the appropriate financial and reputational incentives. We show that capital markets in Argentina, Chile, Mexico, and the Philippines do react to announcements of environmental events, such as those of superior environmental performance or citizens' complaints. A policy implication is that environmental regulators in developing countries may explicitly harness those market forces by introducing structured programs of information release pertaining to firms' environmental performance: public disclosure mechanisms in developing countries may be a useful model to consider given limited government enforcement resources.  相似文献   
2.
The present study investigates the immobilization of Pb(II), Cd(II) and Ni(II) on clays (kaolinite and montmorillonite) in aqueous medium through the process of adsorption under a set of variables (concentration of metal ion, amount of clay, pH, time and temperature of interaction). Increasing pH favours the removal of metal ions till they are precipitated as the insoluble hydroxides. The uptake is rapid with maximum adsorption being observed within 180 min for Pb(II) and Ni(II) and 240 min for Cd(II). A number of available models like the Lagergren pseudo first-order kinetics, second-order kinetics, Elovich equation, liquid film diffusion and intra-particle diffusion are utilized to evaluate the kinetics and the mechanism of the immobilization interactions. Two isotherm equations due to Langmuir and Freundlich showed good fits with the experimental data. Kaolinite and montmorillonite have considerable Langmuir monolayer capacity with respect to Pb(II), Cd(II) and Ni(II), the values being in the range of 6.8-11.5mg/g (kaolinite) and 21.1-31.1mg/g (montmorillonite). The Freundlich adsorption capacity follows a similar order. The thermodynamics of the immobilization process indicates the same to be exothermic with Pb(II) and Ni(II), but endothermic with Cd(II). The interactions with Pb(II) and Ni(II) are accompanied by decrease in entropy and Gibbs energy while the endothermic immobilization of Cd(II) is supported by an increase in entropy and an appreciable decrease in Gibbs energy. The results have established good potentiality for kaolinite and montmorillonite to remove heavy metals like Pb(II), Cd(II) and Ni(II) from aqueous medium through adsorption-mediated immobilization.  相似文献   
3.
Climate change and soil salinity: The case of coastal Bangladesh   总被引:1,自引:0,他引:1  
This paper estimates location-specific soil salinity in coastal Bangladesh for 2050. The analysis was conducted in two stages: First, changes in soil salinity for the period 2001–2009 were assessed using information recorded at 41 soil monitoring stations by the Soil Research Development Institute. Using these data, a spatial econometric model was estimated linking soil salinity with the salinity of nearby rivers, land elevation, temperature, and rainfall. Second, future soil salinity for 69 coastal sub-districts was projected from climate-induced changes in river salinity and projections of rainfall and temperature based on time trends for 20 Bangladesh Meteorological Department weather stations in the coastal region. The findings indicate that climate change poses a major soil salinization risk in coastal Bangladesh. Across 41 monitoring stations, the annual median projected change in soil salinity is 39 % by 2050. Above the median, 25 % of all stations have projected changes of 51 % or higher.  相似文献   
4.
Environmental Chemistry Letters - Climate change is predicted to cause severe loss in agricultural production by increasing disease epidemics and intensifying abiotic stresses. Therefore,...  相似文献   
5.
Environmental Science and Pollution Research - Glucose -mediated one-pot hydrothermal method has been utilized to synthesize hollow spherical MgO-ZnO (xMgO-(1-x)ZnO, x?=?0, 0.2, 0.4,...  相似文献   
6.
Red blooms of Euglena sp. in the floodplain wetland ecosystems of Barak Valley, Assam, India, were found to be induced by high concentrations of NH3-N, NO3, Fe, Mg and to some extent, PO4, Cu and Zn in their water. The trace elements were rapidly accumulated by the bloom organisms to high levels, whereby their concentrations in the water declined, leading to a collapse of the bloom, which tended to reappear as decomposition again led to the release of the nutrients. The bloom also harboured fairly high density of certain other algae and zooplankton, thereby acting as a sub-system within the wetland ecosystem. The bloom is non-toxic and is exploited as a fish food by the fish-farmers who artificially induce a bloom for augmenting the growth of surface-feeding species of fishes.  相似文献   
7.
8.
This paper investigates the effectiveness of protected areas in slowing tropical forest clearing in 64 countries in Asia/Pacific, Africa and Latin America during the period of 2001–2012 by comparing deforestation rates inside and within 10 km outside of the boundaries of protected areas. Annual time series of these deforestation rates were constructed from recently published high‐resolution data on forest clearing from Hansen et al. (2013). For 4,028 parks, panel estimation based on a variety of park characteristics was conducted to test if deforestation was lower in protected areas because of their protected status, or if other factors explained the difference. From a sample of 726 parks established since 2002, a test was also conducted to investigate the effect of park establishment on protection. Findings suggest park size, national park status and management by indigenous people all are significantly associated with effective protection across regions. For the Asia/Pacific region, the test offers compelling evidence that park establishment has a near‐immediate and powerful effect.  相似文献   
9.
Environmental Science and Pollution Research - Coronavirus disease 2019 (COVID-19) has emerged as a significant public health emergency in recent times. It is a respiratory illness caused by the...  相似文献   
10.
Environmental Science and Pollution Research - Agricultural soil acts as a source and sink of important greenhouse gases (GHGs) like methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2)....  相似文献   
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