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1.
In Japan, Environment and Pollution Control Agreements (EPCAs) have been an important local environmental policy tool. This paper aims to define the current functions of EPCAs in Japan based on the author's empirical research. The most important characteristic of EPCAs is that they can set up particular environmental policies according to the locality. The eight functions of EPCAs are: (1) to regulate some activity while national regulations are in preparation, (2) to set standards to protect the area's environment, (3) to regulate major ‘point source polluters’, (4) to regulate substances and issues about which it is difficult to make rules, (5) to regulate activities over which the local governments do not have authority, (6) to reinforce administrative guidance, (7) conflict resolution, and (8) to follow up the Environmental Impact Assessment.The paper contains many case studies to prove the different functions of EPCAs. The paper also examines the environmental effectiveness of the EPCAs.  相似文献   

2.
The cytoplasmic incompatibility in the field population of Culex pipiens complex from China and Japan was studied. The results of the crossing experiments between 11 different strains suggest that some Japanese strains might be possible to be used for control Chinese strains by using male sterile technique, and the heavy infection of wolbachiae in mosquitoes may have some relations with the cytoplasmic incompatibility in the field population of Cx. pipiens complex.  相似文献   

3.
The acid snow/rain model [describedin Part I, Kitada et al., Atmospheric Environment27A, 1061–1076, 1993] was applied to investigate transport/transformation/deposition of acidic species in association with snow-precipitating cloud over the Japan Sea in winter. The model results showed: (1) The snow-precipitating clouds generated by relatively weak convective motions tend to trap aerosols of sulfate and nitrate and soluble gases such as SO2 and HNO3 below cloud levels, thus keeping their concentrations at higher levels than those for no-cloud situations. The mechanisms involved are: transfer of gas- and aerosol-phase species to cloud-phase through absorption and nucleation scavenging, then their transfer from cloud to snow through riming, and subsequent release from sublimating snow back to gas- and aerosol-phases below cloud base. (2) In-cloud oxidation enhanced the overall conversion of SO2 to SO42− by some 25% with respect to no-cloud situation after 12 h. Furthermore, contributions to the oxidation were 77.4%, 21.1% and 1.5% for S(IV)H2O2, S(IV)O2 with catalysts of Fe3+ + Mn2+ and S(IV)O3 reactions, respectively. (3) The sulfate wet deposited by precipitating snow for 12 h was due mostly to in-cloud scavenging and in-cloud oxidation, i.e. 66% by nucleation scavenging and the remaining by in-cloud oxidation of S(IV), while the contribution of below-cloud scavenging was negligible. (4) The adsorption process of HNO3 onto the surface of falling snow was found to account for major below-cloud scavenging of snow, and thus in contrast to SO42−, the below-cloud scavenging contributed very significantly to the nitrate wet deposition. Throughout the stimulation, below-cloud scavenging was responsible for 75% of the snow-NO3 formation. Therefore, taking account of this process in acid snow models is important.  相似文献   

4.
The cytoplasmic incompatibility in the field population of Culex pipiens complex from China and Japan was studied. The results of the crossing experiments between 11 different strains suggest that some Japanese strains might be possible to be used for control Chinese strains by using male sterile technique, and the heavy infection of wolbachiae in mosquitoes may have some relations with the cytoplasmic incompatibility in the field population of Cx. pipiens complex.  相似文献   

5.
1IntroductionUrbanizationisabigproblemnotonlyindevelopedcountriesbutalsoindevelopingcountries.Thisisamodernandurgentafairinth...  相似文献   

6.
In order to clarify the mechanism of spring surface level high oxidant episodes, both upper and surface level ozone observations were carried out from April to June 1983. The results were analyzed using aerological data and AMeDAS (Automated Meteorological Data Acquisition System) data.During the observation period, there were 11 days with high oxidant episodes which were defined as when the recorded ozone concentration exceeded 100 ppb at any of five stations. Meteorological conditions under which the surface episodes occurred were examined for three cases when upper level ozone distributions were observed, and the mechanism of the episode were investigated. In this paper, the analysis for one case is explained in detail. For this case: (i) the peak time of oxidant (ozone) concentration at each surface station was controlled by the transition pattern of photochemical oxidant under the local wind system and (ii) the stratospheric air with high concentrations of ozone intruded into the troposphere through the tropopause gap (tropopause folding) behind the cyclone and continued to descend gradually. In the lower troposphere, it descended further due to the influence of topography, and contributed to high surface oxidant episodes. The descent of stratospheric ozone was related to the position of both cyclones and anticyclones. The other two cases had similar upper meteorological conditions but different surface wind systems such as land and sea breeze.  相似文献   

7.
The heterogeneous loss of HO2 radicals onto ambient aerosols plays an important role in tropospheric chemistry. However, sparse investigation of the dominating parameters controlling the HO2 uptake coefficients onto ambient aerosols(γHO2) has largely hindered the application of the measured γHO2 to the global spatial prediction. Here we induced an offine method using LFP-LIF technique to measure the kinetics of HO2 uptake onto ambient aeroso...  相似文献   

8.
CharacteristicsofchangeofhumicsubstanceinsoilindegradedgraslandsShengXuebinResearchCenterforEcoEnvironmentalSciences,Chinese...  相似文献   

9.
Biodegradation of mixture of VOC''''s in a biofilter   总被引:3,自引:0,他引:3  
IntroductionDeterioratingatmosphericairqualityhasresultinginmorestringentregulationsarebeingenforcedtocontrolairpollutants .Volatileorganiccompounds(VOCs)areamongthenewclassofaircontaminantsgeneratedfromavarietyofindustrialsources .Effortstocontroltheemis…  相似文献   

10.
1 IncreasingenvironmentalproblemscallfortechnologicalsolutionsWiththerapideconomicgrowthinthepasttwodecades,allthemajorenvironmentalproblemsofworldwideconcernhaveappearedinChinainonewayoranother.Theyaremainlyreflectedinsoilerosion,desertification,bi…  相似文献   

11.
Certain enteric viruses that are present in the water environment are potential risk factors of waterborne infections. To better understand the impact of viruses in water, both enteric viruses and their potential indicators should be comparatively investigated. In this study, occurrences of GI- and GII-noroviruses (NoVs), sapovirus (SaV), rotavirus (RoV), Aichi virus 1 (AiV-1), enterovirus (EV), and pepper mild mottle virus (PMMoV) were quantitatively determined in surface water samples in Japan. Additionally, the genotype distribution of GI- and GII-NoVs was determined using a next-generation amplicon sequencing. PMMoV was the most abundant virus regardless of season and location, indicating its usefulness as an indicator for the viral contamination of water. Other potential indicators, AiV and EV, were less abundant than GII-NoV. Viruses other than PMMoV showed seasonality, i.e., EV and other viruses (NoVs, SaV, RoV, and AiV-1) became prevalent during summer and winter, respectively. SaV showed a relatively high abundance at a location that was affected by untreated wastewater. Regarding NoV genotypes, GI.1, GI.2, GI.4, GI.5, GI.6, GII.3, GII.4, GII.6, and GII.17 were found from the surface water samples. GII.4 and GII.17 seemed to have contributed to the high abundance of GII-NoV in the samples. Interestingly, GII.17 strains became prevalent in the water samples before becoming prevalent among gastroenteritis patients in Japan. These findings provide further insights into the properties of viruses as contaminants in the water environment.  相似文献   

12.
Continuous measurements of the methane flux from rice fields in Hangzhou,eastern China,arid Leshan,Sichuan Province,were carried out for 3 years.The results show that the methane flux from rice fields has a strong diurnal variation which may be explained by the soil temperature effects and rice plant growing activities,and that the day-mean flux has a large seasonal variation which may be related to soil temperature and the availability of organic substrate in the soil.An overall sources of methane for China are estimated while the rice fields are major sources,and the sewage tmatment is an important source of methane in China that has not been measure.Sewage in China is often treated in cesspools,which are similar to the biogas pits.However,no methane is recovered from such cesspools.We estimate that the total flux of methane from such sources may be of the oidcr of 10 Tg/a.The total emissions of methane from sources in China are estmmted to be about 40±lOTg/a.  相似文献   

13.
EnvironmentalgeochemicalfeaturesofarsenicinsoilinChinaWengHuanxin,LiuYunfengDepartmentofEarthSciences,ZhejiangUniversity,Hang...  相似文献   

14.
The impacts of petroleum contamination on the litter decomposition of shrub–grass land would directly influence nutrient cycling, and the stability and function of ecosystem. Ten common shrub and grass species from Yujiaping oil deposits were studied. Litters from these species were placed into litterbags and buried in petroleum-contaminated soil with 3 levels of contamination (slight, moderate and serious pollution with petroleum concentrations of 15, 30 and 45 g/kg, respectively). A decomposition experiment was then conducted in the lab to investigate the impacts of petroleum contamination on litter decomposition rates. Slight pollution did not inhibit the decomposition of any litters and significantly promoted the litter decomposition of Hippophae rhamnoides, Caragana korshinskii, Amorpha fruticosa, Ziziphus jujuba var. spinosa, Periploca sepium, Medicago sativa and Bothriochloa ischaemum. Moderate pollution significantly inhibited litter decomposition of M. sativa, Coronilla varia, Artemisia vestita and Trrifolium repens and significantly promoted the litter decomposition of C. korshinskii, Z. jujuba var. spinosa and P. sepium. Serious pollution significantly inhibited the litter decomposition of H. rhamnoides, A. fruticosa, B. ischaemum and A. vestita and significantly promoted the litter decomposition of Z. jujuba var. spinosa, P. sepium and M. sativa. In addition, the impacts of petroleum contamination did not exhibit a uniform increase or decrease as petroleum concentration increased. Inhibitory effects of petroleum on litter decomposition may hinder the substance cycling and result in the degradation of plant communities in contaminated areas.  相似文献   

15.
This study investigated the electrokinetic(EK)behavior of multiple chlorobenzenes,including 1,2,3,4-tetrachlorobenzene(TeCB), 1,2,4,5-tetrachlorobenzene(i-TeCB),and 1,2,3-trichlorobenzene(TCB)in contaminated clayed soils.The effect ofβ-cyclodextrin(β- CD)on the EK removal of the chlorobenzenes was studied.The largest removal was obtained when Na_2CO_3/NaHCO_3 buffer was used as anodic purging solution withoutβ-CD.The removal efficiencies were related to the aqueous solubilities of chlorobenzenes. With the same cumulative electroosmotic flow,greater solubility led to higher removal efficiency.The addition ofβ-CD inhibited the EK removal efficiency of all chlorobenzenes.The inhibition increased with the increase ofβ-CD concentration.With the sameβ-CD concentration,the inhibition increased with the rise of electric potential.It was found that the inclusion compounds betweenβ-CD and chlorobenzenzes were less soluble than chlorobenzenes.The formation of the less soluble inclusion compounds reduced the aqueous solubility of chlorobenzenes and led to the partial immobilization of the chlorobenzenes that desorbed from soil.It was feasible to use the EK technology to remove ehlorobenzenes in contaminated soils using water as the anodic flushing solution.The addition ofβ-CD was not recommended for the EK removal of chlorobenzenes.  相似文献   

16.
The crystal growth of hydroxyapatite (HAP) seeds in presence of the abnormal collagen secreted by the chondrocyte grown in media containing free radical sources or fulvic acid and the type II collagen (pig cartilage) damaged by · OH and fulvic acid(FA) from potable water in endemic region of Kaschin-Beck disease (KBD) was studied. The results showed that in the former case, the abnormal collagen rich in type I collagen promoted mineralization in contrast with the type n collagen. The oxidatively damaged type II collagen became less inhibitive or even promotive. In all cases, the reaction followed a second order kinetics. The powder X-diffraction analysis and SEM observation indicated that the damaged type II collagen lowers the crystalinity in the beginning and made the final crystal more agglomerated. All the results showed that the abnormal and the damaged cartilage matrix affected the bimineralization and was likely to have played an important role in the development of KBD.  相似文献   

17.
IntroductionHealthhazardsfrommercuryintheenvironmenthavecausedrestrictionsintheuseofmercuryandastrictercontrolofthereleaseofmercuryfromindustrialandotheruses.Butatthesametimethesesourcesofmercuryhavebeensubjectedtoregulation ,twonewsourceshaveappeared …  相似文献   

18.
The degradation of pesticide 1-(2-chlorobenzoyl)-3-(4-chlorophenyl)urea(CCU)in water and its accumulation and metabolism in fish were studied using HPLC method.The results of acute toxicity of both CCU and its naetabolites were also reported.The research demonstrated that CCU degraded quickly in aerobic aquatic environment and primary metabolites of CCU were 4-chlorophenyl urea and orthochlorobenzoic acid.Microorganisms play an important role for the degradation of CCU in water.Both the parents compound and its metabolites were not lethal to fish in tested concentration.The accumulation of CCU in fish was sunilar to that of dillubenzuron.The esterase in fish liver which could metabolized CCU was identified.The primary enzymatic degradation products of CCU is the same as that in water.  相似文献   

19.
Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over Beijing. Halogenated compounds such as CFC-11, CFC-12, CHCl_3, CCl_4, CH_3CCl_3, CHCl =CCl_2, and CCl_2=CCl_2 were measured and their concentrations are 109±8, 234±13, 47±22, 97±24, 88±29, 11±1 and 17±3 (pptv), respectively.  相似文献   

20.
1 Determinationoftotalmercuryandspeciationofmercurycompoundsinatmosphere1.1 DeterminationoftotalmercuryAsamplingtrainconsistingofafiltertoretain particulatephasemercuryfollowedbyanabsorbenttrapwhichretainstotalgaseousmercuryisusedfordeterminationoftota…  相似文献   

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