首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The long-term variation, nature and correlations of outdoor 222Rn and 220Rn progeny concentrations measured during the period 1994-2009 were investigated. The time series of data were obtained within the framework of the monitoring program performed by the Environmental Radioactivity Monitoring Station (ERMS) Bac?u, a component part of the National Environmental Radioactivity Survey Network (NERSN), coordinated by National Environmental Protection Agency (NEPA). The measuring method is based on the total beta measurements of atmospheric aerosol filters, using a low background total beta counter and (90Sr/Y) reference standard. Analysis of the time series of progeny concentrations in the low atmosphere makes evident different patterns of variation of these concentrations: diurnal, seasonal and annual. A possible relationship of progeny concentration increase with global warming is emphasized. In order to find the dominant frequency of the physical processes determining progeny concentration variability the power spectrum has been used. The deterministic nature of the time series of concentrations has been studied making use of the autocorrelation function and stationarity of the original data and of their phase randomized time series. Also, the correlations with meteorological parameters have been investigated using Pearson’s correlation coefficient with corresponding level of significance.  相似文献   

2.
The south east basin of France shelters deep CO2 reservoirs often studied with the aim of better constraining geological CO2 storage operations. Here we present new soil gas data, completing an existing dataset (CO2, 222Rn, 4He), together with mineralogical and physical characterisations of soil columns, in an attempt to better understand the spatial distribution of gas concentrations in the soils and to rule on the sealed character of the CO2 reservoir at present time.Anomalous gas concentrations were found but did not appear to be clearly related to geological structures that may drain deep gases up to the surface, implying a dominant influence of near surface processes as indicated by carbon isotope ratios. Coarse grained, quartz-rich soils favoured the existence of high CO2 concentrations. Fine grained clayey soils preferentially favoured the existence of 222Rn but not CO2. Soil formations did not act as barriers preventing gas migrations in soils, either due to water content or due to mineralogical composition. No abundant leakage from the Montmiral reservoir can be highlighted by the measurements, even near the exploitation well. As good correlation between CO2 and 222Rn concentrations still exist, it is suggested that 222Rn migration is also CO2 dependent in non-leaking areas - diffusion dominated systems.  相似文献   

3.
The fishing and hunting performed by inhabitants of the Extractive Reserve of the Upper Juruá, Acre, Brazil was studied, and an ecological analysis on the use of fish and game, including preferences, taboos and medicinal uses, and of fish abundance was made. Research was carried out at the Upper Juruá Extractive Reserve in three visits (1993 and 1994). A total of 143 individuals (101 families) living along the banks of the rivers Juruá, Tejo, Bagé, S. João and Breu were interviewed, and 115 species of fish with set gillnets were collected. Local economic activities included rubber-tapping and small-scale agriculture. Fishing was especially important in the dry season, when cast net and hook and line were used. Hunting and game consumption were intensive in the wet season. Some local rules may be useful as starting points for local management, such as the use of fish diversity through lake management, the use of water level seasonality, hunting periods or quotas, and food taboos. The integration of academic research with indigenous knowledge and demands is important to develop management plans which protect both biological and cultural diversity.  相似文献   

4.
ABSTRACT

This article considers the format and cultural politics of the hugely successful UK television program Top Gear (BBC 2002–2015). It analyzes how—through its presenting team—it constructed an informal address predicated around anti-authoritarian or contrarian banter and protest masculinity. Regular targets for Top Gear presenter’s protest—curtailed by broadcast guidelines in terms of gender and ethnicity—are deflected onto the “soft” targets of government legislation on environmental issues or various forms of regulation “red tape. Repeated references to speed cameras, central London congestion charges and “excessive” signage are all anti-authoritarian, libertarian discourses delivered through a comedic form of performance address. Thus, the BBC’s primary response to complaints made about this program was to defend the program’s political views as being part of the humor. The article draws on critical discourse analysis and conversation analysis to consider how the program licensed a particular form of engagement that helped it to deflect criticisms, and considers the limits to such discursive positioning. We conclude by examining the controversies that finally led, in 2015, to the removal of the main presenter, Jeremy Clarkson, and the ending of this version of the program through the departure of the team to an on-demand online television service.  相似文献   

5.
New best estimates for the solid–liquid distribution coefficient (Kd) for a set of radionuclides are proposed, based on a selective data search and subsequent calculation of geometric means. The Kd best estimates are calculated for soils grouped according to the texture and organic matter content. For a limited number of radionuclides this is extended to consider soil cofactors affecting soil–radionuclide interaction, such as pH, organic matter content, and radionuclide chemical speciation. Correlations between main soil properties and radionuclide Kd are examined to complete the information derived from the best estimates with a rough prediction of Kd based on soil parameters. Although there are still gaps for many radionuclides, new data from recent studies improve the calculation of Kd best estimates for a number of radionuclides, such as selenium, antimony, and iodine.  相似文献   

6.
Reservoirs have a wide variety of uses that have led to frequent conflicts over ecological conservation and contamination, especially as land management has intensified. Oligotrophication must be implemented in numerous tropical reservoirs that experience advanced eutrophication to maintain aquatic ecosystem functions. To quantify impacts on ecosystem functions and to develop an adaptive management policy, multiple studies have been conducted on the Itaparica Reservoir, São Francisco River, in the semi-arid north-eastern region of Brazil. Here, we add to that existing body of knowledge through investigating how nutrient accumulation is affected by water exchange between the main river flow and Icó-Mandantes Bay. Operational water-level fluctuations in the reservoir create large desiccated littoral areas that release high amounts of nutrients when they are rewetted. In particular, water-level variation promotes proliferation of Egeria densa, a noxious weed, thus elevating trophic levels of the Itaparica Reservoir and Icó-Mandantes Bay. Analysis with a P efficiency model determined 25 μg P L?1 to be the critical concentration and further indicated that the critical load in both bodies of water have been exceeded. Moreover, intensive fish aquaculture using net cages has led to further overtaxing of the reservoir. We conclude that an effective ecological reservoir management policy must involve oligotrophication, harvesting of noxious water weeds for use as soil amendment in agriculture or biogas production, “blue” aquaculture, and limiting hydroelectric power production based on current water availability.  相似文献   

7.
创意农业,作为农业的新型产业业态和都市型农业转型升级的重要标志,成功实现了创意产业与传统农业生产的有机结合,有力促进了首都都市型现代农业的转型升级。然而,北京市创意农业在发展过程中呈现出多形态、不平衡的发展现状,为促进北京市创意农业的平衡与快速发展,本文以创意产业发展为背景,综合考虑多种变量对创意农业发展的影响,运用自适应多变量MGM(1,n)灰色预测模型,分别对北京2011-2015年不同形式创意农业发展规模与发展方向进行预测。研究发现:在发展规模上,伴随着北京创意产业与农业生产等不断发展,未来五年内北京创意农业总产值将不断增长;在发展方向上,北京创意农业中的农业观光园、民俗旅游、设施农业产值都将不断增长,其中农业观光园产值最大,且其收入增长速度最快,而民俗旅游不仅产值低,而且增长最为缓慢。因此,应在保证农业观光园和设施农业的扶持力度的基础上,加大对民俗旅游的支持力度,加速民俗旅游的发展速度,以促使北京市创意农业全面、平衡发展。  相似文献   

8.
在2007年8月研究的基础上,于2008年7月在神农架大九湖泥炭藓沼泽湿地采用自制简易模拟装置进行现场模拟实验,深入研究了泥炭藓沼泽湿地对不同浓度的金属污染物镉(Ⅱ)、铜(Ⅱ)、铅(Ⅱ)、锌(Ⅱ)的净化作用。研究表明:泥炭藓沼泽湿地对各种金属污染物都有很强的去除能力,2小时后的去除效果强弱顺序为Pb>Cu>Cd>Zn;4种金属任一时刻的去除速率都随初始浓度的增加而增大,低初始浓度先于高初始浓度达到平衡;泥炭藓沼泽湿地的稀释功能在污染物去除中起着重要作用。通过双常数速率模型得到了去除速率与实验时间的关系;拟二级动力学模型和修改后的拟一级动力学模型能够很好地描述泥炭藓沼泽湿地去除金属污染物的动态过程,拟二级动力学模型的拟合效果更佳,通过修改后的拟一级动力学模型可以计算出稀释作用对湿地净化的贡献率。为评估泥炭藓沼泽湿地净水价值、保护和合理利用泥炭藓沼泽湿地提供科学依据。  相似文献   

9.
本文比较了美国和中国的一些地区儿童血铅调查和研究成果,证明儿童血铅(BL)与土壤含铅量(SL)直接相关,土壤铅已经成为儿童铅暴露的主要来源。当土壤含铅量超过500–600 mg/kg时,长期暴露在这种土壤环境下的儿童血铅浓度超过10μg/dL是可以预期的。中美儿童血铅模型(IEUBK模型)的实际计算结果也表明,当表层土壤含铅量超过600 mg/kg时,其土地利用不适合任何儿童活动。为了更好地预防儿童高血铅,我国土壤修复的标准可定为居住用地Pb≤250 mg/kg,非居住用地Pb≤600 mg/kg。  相似文献   

10.
Introduction The Sustainable Cities Programme (SCP) is a joint UN-HABITAT/UNEP facility established in the early 1990s to build capacities in urban environmental planning and management. The programme targets urban local authorities and their partners. It is founded on broad-based stakeholder participatory approaches.  相似文献   

11.
The objective of this study was to provide operational probability density functions (PDFs) for distribution coefficients (Kds) in freshwater, representing the partition of radionuclides between the particulate and the dissolved phases respectively. Accordingly, the Kd variability should be considered in uncertainty analysis of transport and risk assessment models. The construction of PDFs for 8 elements (Ag, Am, Co, Cs, I, Mn, Pu and Sr) was established according to the procedure already tested in Durrieu et al. [2006. A weighted bootstrap method for the determination of probability density functions of freshwater distribution coefficients (Kds) of Co, Cs, Sr and I radioisotopes. Chemosphere 65 (8), 1308–1320]: (i) construction of a comprehensive database where Kds values obtained under various environments and parametric conditions were collected; (ii) scoring procedure to account for the ‘quality’ of each datapoint (according to several criteria such as the presentation of data (e.g. raw data vs mean with or without replicates), contact time, pH, solid-to-liquid ratio, expert judgement) in the construction of the PDF; (iii) weighted bootstrapping procedure to build the PDFs, in order to give more importance to the most relevant datapoints. Two types of PDFs were constructed: (i) non-conditional, usable when no knowledge about the site of concern is available; (ii) conditional PDFs corresponding to a limited range of parameters such as pH or contact time; conditional PDFs can thus be used when some parametric information is known on the site under study. For 7 other radionuclides (Ba, Be, Ce, Ra, Ru, Sb and Th), a simplified procedure was adopted because of the scarcity of data: only non-conditional PDFs were built, without incorporating a scoring procedure.  相似文献   

12.
56 250 2.7 32 3780 1560 2.910、男女睡异(X 100%)13、食物保障 8劳动力” .土识字率197011985平均 受教育年限1980撬196D中学、学闯987尸1988大学、孕减1987~88,轰:t物进口依搜率(%) 82中国123印度所有发展 中国家西方国家1046人均t物生产指数〔1979 81哭IDO)农业生产‘占DP%l公召吕人均每日热供给t(卡)1986196斗11匀86谷钧进口(1000公吨)1988食物援助(百万美元〕198公︸一二划幻1006 43 50 32 50 97 56 47 34~71谷物实物扭助(占谷物进口之 比)l匀87~88155172嘿杰戮ID凌。4 546口53已2 91 7D 54砂l7621702240每日热供给,(占必须的百分…  相似文献   

13.
l、人文发展指数┌────┬─────┬────┬────┬───┬──────┬───┬──┬─────┐│ │平均 │成入 │乍熏冷 │教育 │ 实际 │调整 │人文│口戈P ││ │寿命 │识字 ├────┤获相翻│ 入均 │后的 │发展│排位 ││ │了l,q八、│率(%) │教育 │率 │ 召川〕│实际 │指教│ 一,r ││ │ │(1 985) │年故 │ │匕 │拐阴钾│ ├─────┤│ ├─────┤ │t 19日O)│ │ (尸尸尸$) │ │ │排枯 ││ │ │ │ │ │ 19吕5~ │ │ │ ││ │ │ │ │ │ 1勺3协 │ │ │ │├────…  相似文献   

14.
Activity profiles of excess 210Pb determined in three sediment cores from Amazon River mouth, Macapá city, Brazil, provided the evaluation of sedimentation rates, contributing to a better knowledge of the hydrological conditions in the site that is the capital of Amapá State and is drained by the waters of the huge Amazon River. Chemical data were also determined in the sediments, allowing identify signatures coupled to anthropogenic inputs held in the past in Amapá State. Significant direct relationships between LOI (loss on ignition) and organic matter were found for all sediments profiles. Silica was found to be inversely related to organic matter in the three profiles; its decrease accompanied an increase on the specific surface of the sediments. This relationship was confirmed by a great number of inverse significant correlations among silica and oxides Na2O, K2O, CaO, MgO, Al2O3, P2O5, Fe2O3 and MnO. It was possible to identify the role of organic matter on adsorption of several oxides in the core sediments profiles. Apparent sediment mass accumulation rates corresponding to values between 450 and 2510 mg cm−2 yr−1 were obtained, and are compatible with the results of others studies. The 210Pb activities in one sampling point suggested the occurrence of anthropogenic inputs related to the initial period of the mining activities conducted in Serra do Navio, Amapá State, for the commercialization of Mn ores. This was reinforced by the abrupt fluctuations in chemical data obtained for the sediments and composition of the interstitial waters occurring there. The Atlantic hurricane activity also appeared to affect the sedimentation rates in the area, as two different values were recorded in each profile.  相似文献   

15.
Transuranics and fission products have been measured in lake sediment samples, collected in an alpine wetland, to determine their vertical distribution and calculate inventories. The radionuclides considered are 90Sr, 137Cs, 238Pu, 239/240Pu and 241Am. From the results, a better knowledge of radionuclide accumulation mode and behaviour was obtained. In addition, the origins of the individual pollutants could be deduced from activity ratios. Analyses were made on different sediment cores. The sampling sites were chosen to enable future determination of the mass balances of the radiopollutants. As the selected study area is in a recreational area used by urban populations, a rough estimate was made of the mean external dose from 137Cs for comparison with the French regulation.  相似文献   

16.
BackgroundStudies measuring health effects of Saharan dust based on large particulate matter (PM) fraction groups may be masking some effects. Long distant transport reduces the amount of heavier and larger particles in the Saharan air masses increasing the relative contribution of smaller particles that may be more innocuous. This study investigates the association between different PM fractions and daily mortality during Saharan and non-Saharan days in Barcelona, Spain.MethodsWe collected daily PM1, PM2.5–1 and PM10–2.5 fractions, and cause-specific mortality (cardiovascular, respiratory and cerebrovascular) between March 2003 and December 2007. Changes of effects between Saharan and non-Saharan dust days were assessed using a time-stratified case–crossover design.ResultsDuring non-Saharan dust days we found statistically significant (p < 0.05) effects of PM10–2.5 for cardiovascular (odds ratio for increase of an interquartile range, OR = 1.033, 95% confidence interval: 1.006–1.060) and respiratory mortality (OR = 1.044, 95% CI: 1.001–1.089). During Saharan dust days strongest cardiovascular effects were found for the same fraction (OR = 1.085, 95% CI: 1.017–1.158) with an indication of effect modification (p = 0.111). Effects of PM2.5–1 during Saharan dust days were about the double than in non-dust days for cardiovascular and respiratory mortality, but these differences were not statistically significant.ConclusionOur results using independent fractions of PMs provide further evidence that the effects of short-term exposure to PM during Saharan dust days are associated with both cardiovascular and respiratory mortality. A better understanding of which of the different PM size fractions brought by Saharan dust is more likely to accelerate adverse effects may help better understand mechanisms of toxicity.  相似文献   

17.
A selection of PBDE congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbor porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic white-sided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986–2009). The analytes were extracted and cleaned-up using open column extraction and multi-layer silica gel column chromatography, and the analysis was performed on a GC-MS system operating in the NCI mode. The highest PBDE levels were found in the toothed whale species pilot whale and white-sided dolphin, and the lowest levels in fin whales and ringed seals. One-sided analyses of variance (ANOVA) followed by Tukey comparisons of means were applied to test for differences between years and sampling areas. Due to inter-year sampling variability, only general comparisons of PBDE concentrations between different sampling areas could be made. Differences in PBDE concentrations between three sampling periods, from 1986 to 2007, were evaluated in samples of pilot whales, ringed seals, white-sided dolphins and hooded seals. The highest PBDE levels were found in samples from the late 1990s or beginning of 2000, possibly reflecting the increase in the global production of technical PBDE mixtures in the 1990s. The levels of BDE #153 and #154 increased relative to the total PBDE concentration in some of the species in recent years, which may indicate an increased relative exposure to higher brominated congeners. In order to assess the effect of measures taken in legally binding international agreements, it is important to continuously monitor POPs such as PBDEs in sub-Arctic and Arctic environments.  相似文献   

18.
中国动植物主要门类已知种(或属)和特有种(或属)的状况   总被引:1,自引:0,他引:1  
我国生态系统类型多 ,物种多 ,遗传资源丰富 ,生物多样性保护任务十分繁重。哺乳类的已知种有 581种 ,特有种有 1 1 0种 ,占总种数的 1 8.93% ;鸟类的已知种有 1 2 4 4种 ,特有种有 98种 ,占总种数的 7.88% ;爬行类的已知种有 376种 ,特有种有 2 5种 ,占总种数的 6.65% ;两栖类的已知种有 2 84种 ,特有种有 30种 ,占总种数的 1 0 .56% ;鱼类的已知种有 3862种 ,特有种有 40 4种 ,占总种数的 1 0 .46% ;被子植物的已知属有 31 2 3属 ;特有属有 2 4 6属 ,占总属数的 7.5% ;裸子植物的已知属有 34属 ,特有属有 1 0属 ,占总属数的 2 9.4% ;蕨类…  相似文献   

19.
利用2010—2016年济南市环境空气质量监测数据,分析了济南市PM_(2.5)的年变化、月变化、日变化和区域分布特征。结果表明:(1)跑马岭监测点(远离市区的清洁对照点)PM_(2.5)浓度呈逐年下降的趋势,其余监测点PM_(2.5)的浓度均在2013年达到峰值后逐渐下降。(2)济南市冬季污染最重,1月达到最高;夏季污染最轻,8月达到最低。(3)PM_(2.5)平均浓度有两个高值中心,不同季节PM_(2.5)高值中心有所不同。(4)夏季,有无逆温时PM_(2.5)差异较小且日变化不明显;冬季,有无逆温时PM_(2.5)差异最大。  相似文献   

20.
长江从宜昌至湖口为中游,全长900 km,其间有四湖地区、洞庭湖区和鄱阳湖区,为湿地集中地带。 
(1) 四湖地区〓位于荆江北岸,属江汉平原,是长江出三峡后第一个大平原湖区,包括长湖、三湖、白露湖和洪湖,总面积原有11000 km2,现有1793 km2,耕地面积约454万hm2,人口450万。荆江河水通过新滩口排水闸汇入长江,汛期关闸,靠电力抽排渍涝,枯季开闸自流排水。长江对地下水侧向补给是地下水主要来源。
四湖地区是湖北的“水袋子”,历史上长江、汉江洪水多次在此决堤泛滥。四湖下游江湖相通,每到汛期,长江、汉江洪水倒灌,形成洪泛区。湖区围垦耕地约7万hm2,地势低洼,多为湖积淤泥,排水不畅,存在潜育型、沼泽型渍害。
(2) 洞庭湖区〓位于荆江南岸,总面积原有18730 km2,1950年时有4350 km2,由于不断围湖垦殖,现仅有2691 km2,耕地面积533万hm2,高程在43~26 m。湖区水网密布,土地肥沃,历来为鱼米之乡。洞庭湖为过水性湖泊,接纳湘、资、沅、澧四水和长江松滋、太平、藕池三口来水,由城陵矶注入长江。近百年来,由于长江泥沙沉积湖内,加之围湖垦殖,湖泊容积显著减少,洪涝灾害日趋严重。
(3) 鄱阳湖区〓位于长江南岸,鄱阳湖是我国最大的淡水湖泊,总面积3900 km2,耕地面积约37万hm2,高程在16 m以上。接纳赣、抚、信、饶、修五河来水,经湖口注入长江。湖区16 m以下大多为湖草滩地,已垦耕地一般在湖水退落后种植,汛期湖水涨落频繁,汛后淤积,土质粘性较重,有机物含量高,地势低洼,排水不畅,耕地土壤脱潜过程缓慢。
人类历史活动,从原始游牧狩猎部落演进为农业定居聚落。江汉平原的湿地主体是“云梦泽”,洞庭湖平原的湿地主体是“江南之梦”,春秋战国时期均为楚国皇家猎区。两个湿地生物多样性丰富,生活着大象、犀牛、麋鹿、扬子鳄等。随着历史变迁,水陆交错型湿地逐渐转化为农业用地和聚落用地,最终成为人工湿地和水体湿地。13世纪后,人类开始围湖造田,与水争地。汉朝时代的大象、犀牛灭绝,宋代后成为老虎栖息地,湿地生态结构转为以湖泊湿地为主,成为水禽栖息地和越冬地,生活着天鹅、野鹤、鸳鸯、家雁等,17~18世纪时老虎绝迹,水禽亦成为濒危物种。由于围湖垦殖,人水争地,自然湿地中70%转化为耕地,多样性损失严重,洪涝灾害不断。1998年长江大洪灾后,中央提出 “封山育林、退耕还林、退田还湖、平垸行洪、以工代赈、移民建镇、加固干堤、疏浚河道” 32字方针,其关键是退耕还林、退田还湖,旨在恢复生态。 
  根据历史记载,堤垸始于春秋,南宋时形成围垦高潮,围湖造田普遍。20世纪50年代以来,人口剧增,“以粮为纲” 驱动围垦新高潮,堤垸经济蓬勃发展,带来生态失衡,人水矛盾。必须协调耕地保护与湿地保护矛盾,推行科学耕种和农、牧、渔协调发展,确保湿地总量动态平衡。长江中游江汉平原及两湖地区,河网交错,湖泊密布,应多建国家级自然保护区,争列《国际重要湿地名录》,逐步扩大湿地保护范围,滋润地球之“肾”;发展生态旅游,保护生态环境,重建湿地生物、景观和文化多样性,促进湿地可持续发展。
三峡建库后,长江枯季1~5月份下泄流量有所增加,水位将略有抬高,但仍在建库前天然水位变幅范围内;10月份水库蓄水,下泄流量减少,但三峡水库将实施人工实时调度,确保中下游生产、生活及航运用水需求。四湖地区潜育型、沼泽型渍害农田主要在总干渠两侧的湖盆地带,远离长江,地下水位不受长江水位变化影响,排水状况也不会改变,三峡建库后不会加剧这些地区农田潜育化、沼泽化。10月后水库蓄水,长江水位降低,有利于四湖地区汛后排涝排渍,提前降低湖、田水位和农田地下水位。 三峡建库后,洞庭湖泥沙淤积将会减少,可延长湖泊寿命。长江枯季下泄流量有所增加,城陵矶水位略有升高,但湖区水位仍低于圩区地面3~4 m,不会影响湖区农田自排。每年10月水库蓄水,下泄流量减少,城陵矶附近江水位比建库前降低2 m,湖区水位可尽快退落,对洞庭湖汛后排涝排渍有利。三峡建坝后如遇长江干流发生特大洪水,经三峡水库调蓄后,可减少鄱阳湖及中下游平原湖区分洪的负担和损失。遇鄱阳湖水系发生大洪水时,还可减少下泄流量,降低湖口水位,有利鄱阳湖水排入长江。每年10月三峡水库蓄水,鄱阳湖可提前退水,有利于湖区农田排涝排渍。1~4月下泄流量比建库前略有增加,湖口水位抬升不超过0.6 m,湖区农田地面仍高出长江水位3 m以上,既不会影响枯季排水,也不会加重湖区土壤的地下渍害。
由于三峡建库后,水位随洪、枯季节调蓄变化,结合中下游平原湖区排灌抽提,湖水交换相对频繁,促使水生生物生长茂盛,为水体稀释自净,消纳降解污染提供有利条件。三峡工程建成后,防洪、发电、航运等综合效益和有利影响将得到充分发挥,并采取有效措施,使不利影响得到减免。随着时间的推移,水利、水电、航运、农业、水产、湿地及自然资源的逐步开发,环境保护和湿地保护必将统筹安排、综合利用、协调发展。三峡工程将有力地保护湿地、保护环境。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号