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1.
Column leaching tests were performed to probe the effect of simulated acid rain at different pH values on the acidification of grey-brown purplish soil from the Three Gorges Reservoir Region. The results indicated that the lower the acid rain pH value the more serious the acidification of the soil; the electric conductance of the solution leaching through different soil layers increased at first, then decreased, while the pH value of leachate changed reversely. In general, the higher the pH value and CEC content of the soil were, the greater the electric conductivity of the leachate was. The releasing amount of base ions in four types of typical soils increased with increasing rain acidity, while the leaching amount of aluminium in four types of typical soils increased with the decline of acid rain pH. Changes in the physical and chemical properties of respective soil layers to different degrees were detected after the addition of simulated acid rain of different pH values.  相似文献   

2.
安徽主要土壤酸碱性及其酸缓冲性能研究   总被引:12,自引:2,他引:12  
为了解安徽省土壤酸碱性分布状况和影响因素、以及未来酸雨可能给土壤带来的酸化影响,选取采集了安徽省不同地理区域4种主要土壤的0~20 cm表层样品,通过收集资料、室内测定和相关性分析研究了土壤酸碱性和酸缓冲容量的大小、分布规律及其影响因素。结果表明,安徽主要土壤pH值和酸缓冲容量均呈现由北向南依次递减趋势;pH值大小顺序为:潮土>砂姜黑土>水稻土>红壤,土壤酸碱性与年均降水量、交换性铝、交换性酸和水解性总酸度均呈极显著正相关(r2=0.7010~0.9039**);土壤酸缓冲容量大小顺序为:潮土(87.6 mmol/kg)>砂姜黑土(36.4 mmol/kg)>水稻土(29.2 mmol/kg)>红壤(23.0 mmol/kg),土壤酸缓冲容量与土壤pH值、土壤阳离子交换量和土壤盐基饱和度均呈极显著正相关(r2=0.7631~0.9494**);由此可见安徽几种主要土壤的酸碱性存在很大差异,土壤基本性质和环境条件强烈影响着土壤酸碱性和对酸的缓冲性能,由此也必然影响着土壤受酸雨影响的后果。  相似文献   

3.
The effects of flooding and subsequent air-drying on NH_4~+ adsorption and the release of nitrogen of typical soils adsorbed ammonia in Three Gorges reservoir were studied in the laboratory.The influence of adsorption and release of soils in Three Gorges Reservoir on Aquatic Environment Quality was also studied.The results show that: 1) The adsorption ability is enhanced by flooding and subsequent air-drying.The capacity of the ammonia adsorption capacity was increased from 666 mg/kg to 833 mg/kg.2) Nitrogen,which has been adsorbed by sample soils in drawdrown area of Three Gorge area,is released under simulating flooding condition.The more the soil adsorbed,the more the nitrogen released.The ratio between aerobic condition and anaerobic condition is 1.2~1.4.3) The soils in drawdrown area of Three Gorge Reservoir can adsorb nitrogen from surface runoff,and during submersion periods the nitrogen is released.The risk of Eutrophication is increased in Three Gorges Reservoir.  相似文献   

4.
紫色土中联苯菊酯残留对土著微生物的影响   总被引:1,自引:1,他引:0  
为了阐明紫色土农药残留的生态环境效应特征及土壤微生物响应机理,以三峡库区具代表性的紫色土为材料,通过玉米盆栽模拟试验和平板计数法,研究了残留态联苯菊酯对紫色土土著微生物数量的影响。结果表明,低浓度联苯菊酯对土著细菌和放线菌有显著的促生效应,依联苯菊酯浓度从低到高,土壤细菌和放线菌数量随时间逐次出现最高峰值:第6天,LB-L处理下的细菌和放线菌数分别达9.02×106 个/g和2.77×106 个/g,约为相应对照的9倍和3倍;第11天,LB-M的细菌数约为对照的77倍,达到5.19×107 个/g;第16天时,LB-H的细菌数为1.71×107 个/g,LB-M和LB-H处理下的放线菌数分别为4.04×106 个/g、4.35×106 个/g。其次,联苯菊酯残留对土著真菌有显著且迅速的抑制作用,即使在2.50 mg/kg残留水平下,真菌数量也会在施加联苯菊酯后第2天发生显著降低。再次,紫色土中3种土著微生物类群对残留态联苯菊酯均表现出一定的生态适应性,但表现有所不同:土著细菌的生态响应存在阈值,土著放线菌表现为较长时期内稳定的促生效应,土著真菌则表现为可恢复的抑制效应。试验表明,土壤微生物数量等生物因素可作为联苯菊酯对紫色土根际微生态影响的重要评价指标。  相似文献   

5.
Laboratory column leaching tests were conducted with simulated acid rain with pH values of 2.50,3.50,4.50 and 5.60 respectively,to study yellow soil taken from the Three Gorges Reservoir Region.The results showed that the buffer function of yellow soil against acid rain weakened after a long time of leaching,and acid rain of a lower pH exerted stronger impact on the acidification of the soil.The electric conductance (EC) of the leachates through different soil layers first increased,and then decreased.There is an EC peak occurred in the range of simulated acid rain addition,with the shape of the peak obviously different.The Al leaching loss of the soil increased when the acid rain was more acidic.  相似文献   

6.
After the dam of the Three Gorges is built, the raising water will inevitably cause the revival of the part of ancient landslide and the generation of new landslide ,which will influence the town development and traffic safety in the Three Gorges Reservoir Area. In the light of the specific conditions of the Three Gorges Reservoir Area, this paper, taking Fengdu's MingShan landslide in Chongqing for an example, has considered ten typical calculative projects, offered the correspondent load systems acting on the sliding mass and put forward the analytical and calculative method to evaluate the stability of a landslide. The ten typical calculative projects include dry season(natural state), raining season (rainstorm or rain for a long period of time), dry season and water level (175m ) of the reservoir, raining season and water level (175 m) of the reservoir, dry season and earthquake, raining season and earthquake, dry season and water level (175 m ) of the reservoir and earthquake, raining season and water level (175 m) of the reservoir and earthquake, dry season and water level lowered from 175 m to 145 m, raining seasons and water level lowered from 175 m to 145 m, and so on.  相似文献   

7.
在三峡库区典型紫色土坡耕地,设置了四种生态种植模式,进行经济和生态环境效应的研究。结果表明:投入产出比,梨×连翘/花生>桃×连翘/花生>桃/花生>梨/花生>CK,其中梨×连翘/花生与桃×连翘/花生模式分别比对照提高69.9%和65.5%,;影响果树冠幅的主要因子是土层厚度、坡位与种植模式;套种连翘的二种模式须根量明显比其它模式高,树种根系分布特征、种植密度和土层厚度是影响须根量的主要因素;种植模式和坡位均显著影响土壤孔隙度的发育,各种植模式的土壤孔隙度顺序:梨×连翘/花生>桃×连翘/花生>桃/花生>梨/花生  相似文献   

8.
以呼伦贝尔市农牧交错区典型土壤(黑土、黑钙土、暗棕壤、草甸土、栗钙土)为研究对象,对比研究不同土壤剖面发生层次容重、机械组成、有机碳、全氮、全磷等理化特征的分布规律。结果表明:在呼伦贝尔市农牧交错区,典型土壤有机碳、全氮、全磷均表现出随土壤剖面深度的增加而降低的趋势,而土壤容重、pH值的变化出现相反的趋势,且不同利用方式下土壤容重、有机碳、全氮、全磷含量的累积量不同,牧草地土壤>农田土壤。不同土壤类型有机碳:黑钙土>黑土>栗钙土>草甸土>暗棕壤;全氮:黑钙土>黑土>栗钙土>草甸土>暗棕壤;全磷:栗钙土>黑土>暗棕壤>草甸土>黑钙土。在所有典型土壤中,全钾和机械组成在土壤剖面层次上无明显规律。  相似文献   

9.
Under natural conditions,a total of 36 growth sites for Artemisiae annie L. in Three Gorges Reservoir Region were selected. Factors affecting the artemisinin content in A. annie leaves were researched by principal component analysis. Results showed that the accumulative contribution rate of the first three principal components was 89. 258 6%,which represented the whole information of relevant factors of artemisinin content. Principal component 1 was the sunlight and soil factor of A. annie,principal component 2 was the three-dimensional climate factor,and principal component 3 was the biomass factor. The 36 growth sites of A. annie were classified into four categories. According to the planting needs of artemisinin,the most suitable planting sites for sunlight and soil factor and three-dimensional climate factor were Youyang County and Xiushan County,which were consistent with the actual harvesting sites of raw materials in Three Gorges Reservoir Region.  相似文献   

10.
Under natural conditions,wild Artemisiae annie in 36 sampling sites of Three Gorges Reservoir Region were researched. Grey correlation analysis of influencing factors of artemisinin content in A. annie was carried out. Results showed that soil alkali-hydrolyzable N and P were the most significant factors affecting artemisinin content in wild A. annie in Three Gorges Reservoir Region. It could be concluded that artemisinin content in A. annie was mainly affected by the soil nutrient.  相似文献   

11.
为了解三峡库区花岗岩母质不同经济林模式的土壤养分状况,研究了各模式下土壤pH、有机质、全量养分和速效养分的特征,并利用主成分分析法对不同模式的土壤质量进行了综合评价。结果表明,除土壤pH外,经济林土壤有机质、全氮、全磷、全钾、碱解氮、有效磷、速效钾等含量的变异较宽,为中等变异。随土壤层次的增加,各模式下土壤有机质、全氮、速效氮、速效磷和速效钾含量呈递减趋势,而全磷和全钾则存在不规律变化。土壤有机质、全氮和速效钾对经济林土壤质量的高低产生着主要作用,土壤养分综合排名表现为柑橘(精细管理)>柑橘(常规管理)>板栗林>茶园。因此,利用生物措施和精细化管理措施,可有效提高该区域经济林的土壤质量。  相似文献   

12.
为研究酸雨环境下老旧砌体抗压力学性能退化规律,实验室配置了PH值分别为1.5、2.5和3.5的3种硫酸和硝酸混合溶液来模拟酸雨环境,采用完全浸泡加速腐蚀的试验方法对砖、砂浆和砖柱进行不同程度的腐蚀,并测定其抗压强度。试验表明,随着腐蚀时间的增加,砂浆试块抗压强度先增大后降低;砖试块抗压强度随腐蚀时间的增加而降低;模拟酸雨溶液PH值越小,砂浆和砖试块抗压强度降低程度也愈大;砖柱极限承载力和弹性模量均随腐蚀时间的增加而降低,且模拟酸雨溶液PH值越小,降低程度愈大;随着腐蚀时间的增加,砖柱初始刚度逐渐减小,极限破坏位移增大;模拟酸雨溶液PH值越小,砖柱在达到峰值荷载时的变形值越小,脆性愈大;基于试验结果,建立了酸雨环境下砖柱应力应变曲线上升段统一数学表达式及酸雨侵蚀后普通烧结粘土砖砌体剩余抗压强度回归公式。  相似文献   

13.
With GC/MS Approach, PAHs in raw water and effluent of six water purification plants in Three Gorges Reservoir Area are analyzed quantificationally. Six species of PAHs such as acenaphthene, phenanthrene, anthracene, pyrene, fluoranthene and acenaphthylene are determined. Of which, fluoranthene is priority pollutant firstly listed by SEPA. The results show that there are several variety of PAHs in raw water and effluent in water purification plants of Three Gorges Reservoir Area, but on the whole, PAHs concentration level is low. The results also show that PAHs removal capacity of conventional water treatment techniques is poor.  相似文献   

14.
孙盼盼  尹珂 《中国农学通报》2014,30(29):115-119
目前在三峡库区消落带耕种行为给三峡库区带来生态环境恶化,通过经济补贴让农户弃耕可以防治库区生态环境恶化。采用意愿调查法,对库区消落带沿岸农户进行随机入户调查。以农户受偿意愿为依据,估算经济补贴标准,并分析影响补贴意愿值的因素。分析统计数据得出:(1)农户对消落带土地依赖性很强,72.1%的农户在消落带土地上有农作行为;(2)农户对消落带生态环境问题感知度高,94.7%的农户愿意接受经济补贴放弃消落带耕地;(3)对农户的补贴意愿值进行加权求平均值得到549.7元/年·户的受偿平均值;(4)农户补贴意愿值与消落带耕地面积呈显著正相关。  相似文献   

15.
In this paper, the possible geological disasters in Three Gorges Reservoir Area are reviewed. Firstly, the types of geological disasters are classified and their influencing factors and growth characteristics are analyzed, then the damages, which have happened in this area up to now, are listed. On this basis, five aspects of dangers brought by geological disasters to society and economic environment are analyzed. Finally, a conclusion was drawn that the geological disasters in Three Gorges Reservoir Area have done some harms to this area and the situation becomes worse than before. So some reasonable measures should be taken quickly.  相似文献   

16.
Water level fluctuation zone(hereinafter referred to as "WLFZ") is a transitional ecosystem between terrestrial ecosystem and aquatic ecosystem,and also a key area to control its neighboring terrestrial and aquatic ecosystem. After the Three Gorges Reservoir was put into use,ecological environment of its WLFZ has aroused wide concern from domestic and foreign experts. On the basis of introducing characteristics of WLFZ of the Three Gorges Reservoir,current ecological environment and main problems of this area were analyzed,plant selection and configuration was elaborated as well as the implementation effect of many WLFZ protection and ecological restoration modes. In view of the actual conditions,pertinent suggestions were proposed for WLFZ of the Three Gorges Reservoir,namely classified protection and ecological restoration,enhancing monitoring and assessment of current situation and change tendency,carrying out technical researches and demonstration of WLFZ wetland ecological restoration.  相似文献   

17.
三峡水库投入使用后,在库区两岸形成周期性变化的水陆交错地带即消落区。通过调查消落区的类型、分布、面积等基本情况,从消落区水、土相互作用角度,分析了消落区在水、土交互作用下对水、陆生态系统的影响,提出了利用生物缓冲带等技术来建立消落区生态保护的措施。  相似文献   

18.
为了减少土壤对农业造成的损失以及给生态环境带来的恶化,为保证湖南农业的可持续发展和生态环境保护提供科学依据,以长沙市东郊浏阳河沉积物发育的冲积菜园土为研究对象,通过田间小区试验和动态取样与室内测定,研究了不同施肥结构对菜园土酸性、交换性能的改良效应。结果表明:单纯施用化学肥料处理(NPK)能明显降低土壤pH,施用石灰质物质处理(NPK+MgO和NPK+CaO)能有效降低表层土酸酸度;交换性铝离子只有在较低酸度的土壤中出现;耕层土壤CEC值相对比较稳定,试验土壤CEC值在8~10.75 cmol/kg之间,平均值为9.05 cmol/kg。供试土壤的保肥和酸化缓冲能力比较弱。  相似文献   

19.
The eutrophication of water body will destroy the balance of ecological environment.To determine the total nitrogen content in water body exactly,is one of the most important evaluating indicators that whether the water body has been polluted by eutrophication or not.After the foundation of the Three Gorges Reservoir,current velocity lowers and it may result in the eutrophication of water body.In terms of the Lambert-Beer Law,the authors adopt potassium sulpersulphate oxidation-ultraviolet spectrophotometry to determine the total nitrogen content in the Three Gorges Reservoir.By analyzing a variety of possible factors,they bring forward a method to determine the total nitrogen which can be used in lab and also have high performance.With this improved method,the authors determine the factual water samples of the Three Gorges Reservoir in the main urban area of Chongqing,and the result is that the total nitrogen content is(0.6~1.0) mg/L,less than the limiting value(2.0 mg/L) in national standard.So the water body of the Three Gorges Reservoir still eutrophication does not take place.So eutrophication does not take place in water body of the Three(Gorges) Reservior.  相似文献   

20.
庞冰  方宝华 《中国农学通报》2011,27(30):126-130
为进一步挖掘饲料专用早稻产量潜力,提高其糙米蛋白质含量,通过总结专用稻栽培技术,选取了湖南省五类土壤,研究饲料专用早稻的产量和稻米品质变化。结果表明,五类土壤种植的饲料专用早稻产量以黄泥(6358.5 kg/hm2)为最高,其次为灰黄泥(6295.5 kg/hm2),产量表现为黄泥 > 灰黄泥 > 红黄泥 > 紫潮泥 > 中性紫泥;黄泥、灰黄泥、红黄泥比紫潮泥、中性紫泥的饲料稻全生育期缩短1天;灰黄泥具有较高的糙米率和蛋白质含量,糙米率为80.1%,蛋白质含量为12.2%。综合分析,饲料专用稻的产量、生育期和米质特点,认为最适宜种植饲用稻的土壤为灰黄泥,其次是黄泥和红黄泥。  相似文献   

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