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1.
大家知道吗,现在地球妈妈的身体越来越不干净了,还变得十分虚弱了,所以我们要马上行动起来,保护地球妈妈。我想了一个办法:从自我做起,评选"低碳生活达人"。我把这事告诉了爸爸和妈妈,他俩欣慰地笑了,我们家便开始了低碳生活。瞧,现在爸爸很少开车了,因为车子排放的尾  相似文献   

2.
一到了重要的节日,中国人基本都要烧纸、放鞭炮,我们的传统习惯中,不知不觉制造了许多环境污染。许多人比较尊重传统文化和习惯,而忽略了其中产生的有害气体,不仅危害了自己,同时也危害了他人。  相似文献   

3.
超稠油污水深度处理工艺技术   总被引:2,自引:1,他引:1  
针对辽河油田超稠油污水的特点设计了处理工艺流程,进行了药剂的筛选,根据各工艺设备的出水水质要求确定了合适的净水剂、除硅剂、阻垢剂的加量,并进行了现场实际应用,外输出水达到锅炉给水指标要求,用于锅炉注汽使用,效果良好,分析了该超稠油污水处理技术的特点和优势,提出了超稠油污水回用锅炉的建议。  相似文献   

4.
唐逸 《环境教育》2011,(6):17-18
鸟类是对环境十分敏感的动物,环境改变了,不适于它们生活,它们就飞走了。当然,环境改变了,又适于它们生活了,它们又会飞回来。  相似文献   

5.
系统分析了范庄油田污水处理中水质状况,找出了不达标的原因,提出了如下改进方案:合理加药,强化除油,加强沉降,严格过滤,自动排污,改善收油系统,改进处理工艺流程。实施改进措施后,有效地减少了地层污染,提高了污水回注率,避免了污水外排,同时还减轻了一线工人的劳动强度。  相似文献   

6.
雪之印象     
<正>这个冬天真是地道得很,北半球几乎所有的国家都在下雪。大雪如天使手中曼舞的轻纱,飘洒悠然,覆盖了山脉,封冻了河流,点缀了城乡,染白了大地。大自然用鬼斧神工,雕琢出了雪花,这个季节的精灵。  相似文献   

7.
在上周的星期六,由于我没有把水龙头关紧被妈妈发现了,妈妈狠狠教育了我一顿:"孩子,你要节约水资源呀。就算这水是公家的,我们也不能浪费!"我感到很内疚,默默地走到自己的房间,关上门,静静地思考着。过了一会儿,妈妈敲了敲门,进来又说:"以后不要这样浪费水了,下不为例!"  相似文献   

8.
长株潭城市群核心区大气环境承载力初探   总被引:2,自引:0,他引:2  
胡麓华  张虹 《四川环境》2009,28(5):31-35
对长株潭城市群核心区大气环境质量现状进行了分析,评价了长株潭城市群核心区大气环境承载力,分析了长株潭核心区大气环境承载力发展趋势,提出了提高长株潭核心区大气环境承载力利用水平的建议。  相似文献   

9.
阐述了环保企业集群的定义,分析了环保企业集群的优势,列举了典型范例,给出了环保企业集群发展的建议。  相似文献   

10.
流泪     
刘佳馨 《环境教育》2013,(10):88-88
小朋友们从小草身上践踏过去,小草哭了;小女孩摘下一朵小花,小花哭了;人们随便地砍伐树木,大树哭了;人们往大气中排放污染物,臭氧层哭了;现在的地球已被折磨的千疮百孔,地球哭了……  相似文献   

11.
ABSTRACT: The effects of potential climate change on water resources in the Delaware River basin were determined. The study focused on two important water-resource components in the basin: (1) storage in the reservoirs that supply New York City, and (2) the position of the salt front in the Delaware River estuary. Current reservoir operating procedures provide for releases from the New York City reservoirs to maintain the position of the salt front in the estuary downstream from freshwater intakes and ground-water recharge zones in the Philadelphia metropolitan area. A hydrologic model of the basin was developed to simulate changes in New York City reservoir storage and the position of the salt front in the Delaware River estuary given changes in temperature and precipitation. Results of simulations indicated that storage depletion in the New York City reservoirs is a more likely effect of changes in temperature and precipitation than is the upstream movement of the salt front in the Delaware River estuary. In contrast, the results indicated that a rise in sea level would have a greater effect on movement of the salt front than on storage in the New York City reservoirs. The model simulations also projected that, by decreasing current mandated reservoir releases, a balance can be reached wherein the negative effects of climate change on storage in the New York City reservoirs and the position of the salt front in the Delaware River estuary are minimized. Finally, the results indicated that natural variability in climate is of such magnitude that its effects on water resources could overwhelm the effects of long-term trends in precipitation and temperature.  相似文献   

12.
The High Plains aquifer (HPA) is the primary water source for agricultural irrigation in the US Great Plains. The water levels in many locations of the aquifer have declined steadily over the past several decades because the rate of water withdrawals exceeds recharge, which has been a serious concern to the water resources management in the region. We evaluated temporal trends and variations in agricultural water use and hydroclimatic variables including precipitation, air temperature, reference evapotranspiration, runoff, groundwater level, and terrestrial water storage across the HPA region for different periods from 1985 to 2020 at the grid, county, or region scale. The results showed that water withdrawals decreased from 21.3 km3/year in 1985 to 18.2 km3/year in 2015, while irrigated croplands increased from 71,928 km2 in 1985 to 78,464 km2 in 2015 in the entire HPA. The hydroclimatic time-series showed wetting trends in most of the northern HPA, but drying and warming trends in the southern region from 1985 to 2020. The groundwater level time-series indicated flat trends in the north, but significant declining in the central and southern HPA. Trends in irrigation water withdrawals and irrigation area across the HPA were controlled by the advancement of irrigation systems and technologies and the management of sustainable water use, but also were affected by dynamical changes in the hydroclimatic conditions.  相似文献   

13.
An attempt was made to investigate the relationship between raw coal characteristics and effluent quality in two coking coal washeries of Central Coalfields Limited, Kedla and Rajrappa in Jharkhand State, India. Coal samples-raw coal feed, washed fine clean coal, washed coarse clean coal, middlings and rejects were collected. Similarly, raw water (intake to washery) and effluent samples generated in the washeries, namely, fine coal jig under water, coarse coal jig under water and slurry pond water were also collected over a period of 6 months. Parameters outlined in Ministry of Environment and Forest (MoEF) Schedule VI Indian standards were determined, both in coal samples and water/washery effluent samples. Apart from the parameters listed in the standard, sodium, potassium, calcium, magnesium, sulphate and chloride found to be present in coal were also determined in coal and water samples. The processing results essentially in production of huge quantities of suspended material, which is beyond the stipulated limit of 100mg/l as specified in the Standard. Lowering of pH was observed in both the washeries. The trace/heavy elements were found to be concentrated in the heavier fractions in rejects produced from the washery. The concentrations of major elements in coal-Na, K, Ca, Mg, and minor elements in coal-Mn; F, SO4 and Cl were found to be higher in process water than in raw water indicating that these elements are transferred from coal to the water in washeries. However, only in the case of Mn, the stipulated limit of the effluent standard was exceeded. Trace elements like As, Se, Hg, Cd, though found to be present in coal, were absent in the process water indicating that these elements are not released by coal during washing.  相似文献   

14.
15.
Human agency plays a key role in the processes of biological invasions. This comprises not only the human role in the configuration of driving forces or in the perception of the impacts, but also the conceptualization of alien species themselves as an environmental problem. This paper examines different stakeholders' positions in bioinvasion processes at different scales, and it looks at their relevance for the management of invasive species. It compares two cases: the invasion process of Dreissena polymorpha in the Ebro River in Spain and the case of Hydrilla verticillata in Lake Izabal, Guatemala. Our results are structured according to impacts and to management options. The discussion focuses on the relevance of incorporating the different stakeholders' interests and values in the analysis and management of biological invasions. Although social analysis of stakeholders' positions is necessary in order to foster management actions, it also reveals conflicts on the relevant criteria and on the very definition of invasive species.  相似文献   

16.
A map of summer total phosphorus in lakes was compiled recently for a three-state area of the upper Midwest for purposes of identifying regional patterns of total phosphorus in lakes and attainable lake trophic state. Spatial patterns in total phosphorus from approximately 3000 lakes were studied in conjunction with maps of geographic characteristics that tend to affect phosphorus balance in lakes to identify regions of similarity in phosphorus concentrations in lakes or similarity in the mosaic of values as compared to adjacent areas. While degrees of relative homogeneity are apparent at many scales, the map was designed at a scale that would yield regions with sufficient homogeneity to be useful for lake management throughout the area. In this study, data from 210 lakes in a 1560-mi2 area in northwestern Wisconsin, sampled by the Wisconsin Department of Natural Resources in the spring of 1988 (subsequent to the compilation of the phosphorus map), were examined to: (1) substantiate the existence of the regions depicted on the map in northwest Wisconsin, (2) determine the nature and relative precision of the regional boundaries, (3) determine the relative importance of natural and anthropogenic watershed characteristics, lake types, lake area, and lake depth in explaining within-region differences in lake phosphorus, and (4) demonstrate how the regions might be used by local lake managers.  相似文献   

17.
River engineers use sediment transport formulas to design regulated channels in which the river's ability to transport bedload would remain in equilibrium with the delivery of materials from upstream. In gravel-bed rivers, a number of factors distort the simple relationship between particle size and hydraulic parameters at the threshold of sediment motion, inherent in the formulas. This may lead to significant errors in predicting the bedload transport rates in such streams and hence to instability of their regulated channels. The failure to recognize a nonstationary river regime may also result in unsuccessful channelization. Rapid channel incision has followed channelization of the main rivers of the Polish Carpathians in the 20th century. A case study of the Raba River shows that incision has resulted from the increase in stream power caused by channelization and the simultaneous reduction in sediment supply due to variations in basin management and a change in flood hydrographs. Calculations of bedload transport in the river by the Meyer-Peter and Müller formula are shown to have resulted in unrealistic estimates, perhaps because the different degree of bed armoring in particular cross-sections was neglected. It would have been possible to avoid improper channelization if the decreasing trend in sediment load of the Carpathian rivers had been recognized on the basis of geomorphological and sedimentological studies. Allowing the rivers to increase their sinuosity, wherever possible without an erosional threat to property and infrastructure, and preventing further in-stream gravel mining are postulated in order to arrest channel incision and reestablish the conditions for water and sediment storage on the floodplains.  相似文献   

18.
ABSTRACT: The Central Nebraska Basins (NAWQA) study unit includes the Platte River and two major tributaries, the Loup and Elkhorn Rivers. Platte River flows are variable in the western part of the study unit because of diversions, but the Loup and Elkhorn Rivers originate in an area of dune sand covered by grassland that generates consistent base flows. More frequent runoff in the eastern part of the study unit also sustains stream flow. Ground water in the study unit has no regional confining units and the system is a water table aquifer throughout. Macroinvertebrate and fish taxa at biological sampling sites in the state were related to stream flow. One of the four wetland complexes identified in the study unit includes habitat for threatened and endangered bird species. The study unit is an agricultural area that includes row crops, both irrigated and nonirrigated in the eastern and southern parts, and rangeland in the Sand Hills of the western part. A water quality assessment will be based on the differences in environmental setting in each of four subunits within the study unit.]  相似文献   

19.
Variability and trends in water‐year runoff efficiency (RE) — computed as the ratio of water‐year runoff (streamflow per unit area) to water‐year precipitation — in the conterminous United States (CONUS) are examined for the 1951 through 2012 period. Changes in RE are analyzed using runoff and precipitation data aggregated to United States Geological Survey 8‐digit hydrologic cataloging units (HUs). Results indicate increases in RE for some regions in the north‐central CONUS and large decreases in RE for the south‐central CONUS. The increases in RE in the north‐central CONUS are explained by trends in climate, whereas the large decreases in RE in the south‐central CONUS likely are related to groundwater withdrawals from the Ogallala aquifer to support irrigated agriculture.  相似文献   

20.
High variability in precipitation and streamflow in the semiarid northern Great Plains causes large uncertainty in water availability. This uncertainty is compounded by potential effects of future climate change. We examined historical variability in annual and growing season precipitation, temperature, and streamflow within the Little Missouri River Basin and identified differences in the runoff response to precipitation for the period 1976‐2012 compared to 1939‐1975 (n = 37 years in both cases). Computed mean values for the second half of the record showed little change (<5%) in annual or growing season precipitation, but average annual runoff at the basin outlet decreased by 22%, with 66% of the reduction in flow occurring during the growing season. Our results show a statistically significant (< 0.10) 27% decrease in the annual runoff response to precipitation (runoff ratio). Surface‐water withdrawals for various uses appear to account for <12% of the reduction in average annual flow volume, and we found no published or reported evidence of substantial flow reduction caused by groundwater pumping in this basin. Results of our analysis suggest that increases in monthly average maximum and minimum temperatures, including >1°C increases in January through March, are the dominant driver of the observed decrease in runoff response to precipitation in the Little Missouri River Basin.  相似文献   

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