A campaign was conducted to assess and compare the personal exposure in L3 of Tianjin subway, focusing on PM2.5 levels, chemical compositions, morphology analysis, as well as the health risk of heavy metal in PM2.5. The results indicated that the average concentration of the PM2.5 was 151.43 μg/m3 inside the train of the subway during rush hours. PM2.5 concentrations inside car under the ground are higher than those on the ground, and PM2.5 concentrations on the platform are higher than those inside car. Regarding metal concentrations, the highest element in PM2.5 samples was Fe; the level of which is 17.55 μg/m3. OC is a major component of PM2.5 in Tianjin subway. Secondary organic carbon is the formation of gaseous organic pollutants in subway. SEM–EDX and TEM–EDX exhibit the presence of individual particle with a large metal content in the subway samples. For small Fe metal particles, iron oxide can be formed easily. With regard to their sources, Fe-containing particles are generated mainly from mechanical wear and friction processes at the rail–wheel–brake interfaces. The non-carcinogenic risk to metals Cr, Ni, Cu, Zn and Pb, and carcinogenic hazard of Cr and Ni were all below the acceptable level in L3 of Tianjin subway.
Conflicts between local people's livelihoods and conservation have led to many unsuccessful conservation efforts and have stimulated debates on policies that might simultaneously promote sustainable management of protected areas and improve the living conditions of local people. Many government‐sponsored payments‐for‐ecosystem‐services (PES) schemes have been implemented around the world. However, few empirical assessments of their effectiveness have been conducted, and even fewer assessments have directly measured their effects on ecosystem services. We conducted an empirical and spatially explicit assessment of the conservation effectiveness of one of the world's largest PES programs through the use of a long‐term empirical data set, a satellite‐based habitat model, and spatial autoregressive analyses on direct measures of change in an ecosystem service (i.e., the provision of wildlife species habitat). Giant panda (Ailuropoda melanoleuca) habitat improved in Wolong Nature Reserve of China after the implementation of the Natural Forest Conservation Program. The improvement was more pronounced in areas monitored by local residents than those monitored by the local government, but only when a higher payment was provided. Our results suggest that the effectiveness of a PES program depends on who receives the payment and on whether the payment provides sufficient incentives. As engagement of local residents has not been incorporated in many conservation strategies elsewhere in China or around the world, our results also suggest that using an incentive‐based strategy as a complement to command‐and‐control, community‐ and norm‐based strategies may help achieve greater conservation effectiveness and provide a potential solution for the park versus people conflict. 相似文献
The inhibition and dispersion of polyepoxysuccinate (PESA, self-manufactured) to inorganic scale was evaluated by scale static beaker test to CaC03 and Ca3(P04)2, stability test to zinc salt, and dispersion test to ferric oxide. The experimental results demonstrated that PESA functioned excellent scale inhibition to CaC03 and Ca3(P04)2, good stability to zinc salt and special dispersion to ferric oxide. Under the water with hardness 500-1200 mg/L, alkalinity 1000 mg/L, and dosage of PESA 31.2 mg/L, PESA scale inhibition ratio reached more than 85.0%. At dosage of PESA 20.8 mg/L inhibition ratio on calcium phosphate reached 38.9%, at optimum dosage of PESA 9.1 mg/L, the stability ratio was up to 96.1%; while at dosage of PESA 3.6 mg/L, transmittance ratio reached 64.4%. Therefore, PESA can be considered a soluble, high effective and versatile inhibitor. 相似文献
Environmental Science and Pollution Research - In the face of the global haze crisis, exploring the driving force of political factors for controlling minute atmospheric particles has become... 相似文献