共查询到20条相似文献，搜索用时 31 毫秒
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南四湖人工湿地建设与管理 总被引：1，自引：0，他引：1
采用生态滞留塘+多级表面流湿地系统的工艺方案建设南四湖人工湿地,使出水水质基本达到《地表水环境质量标准》Ⅲ类水质要求。利用人工湿地的生态经济价值,采取市场化运营的模式,探索"以湿养湿,以收养管"的管理机制,使南四湖人工湿地既能保障南水北调安全顺利进行,又能自身循环发展,取得"保水创收"的双赢效果。 相似文献
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自然湿地与人工湿地生态占补平衡研究 总被引：1，自引：1，他引：0
自然湿地与人工湿地的功能与效益并不完全相同。实现湿地生态占补平衡,必须考虑占补湿地的替代性与同质性。人工湿地与自然湿地的替代性是解决湿地生态占补平衡的关键问题之一。建立自然湿地与人工湿地占补平衡的约束机制,占用自然湿地时,可以新建人工湿地,还可以恢复自然湿地。通过确保自然湿地生态量、生态功能与生态效益的均衡,减少湿地的生态损失。尽可能在同一水文单位或同流域内实现湿地生态占补平衡。资金投入要兼顾现有自然湿地的生态恢复与新建人工湿地。 相似文献
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G. S. Parsonson 《New Zealand geographer》1968,24(2):189-194
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Application of Artificial Neural Networks to Complex Groundwater Management Problems 总被引：4，自引：0，他引：4
Coppola Emery Poulton Mary Charles Emmanuel Dustman John Szidarovszky Ferenc 《Natural Resources Research》2003,12(4):303-320
As water quantity and quality problems become increasingly severe, accurate prediction and effective management of scarcer water resources will become critical. In this paper, the successful application of artificial neural network (ANN) technology is described for three types of groundwater prediction and management problems. In the first example, an ANN was trained with simulation data from a physically based numerical model to predict head (groundwater elevation) at locations of interest under variable pumping and climate conditions. The ANN achieved a high degree of predictive accuracy, and its derived state-transition equations were embedded into a multiobjective optimization formulation and solved to generate a trade-off curve depicting water supply in relation to contamination risk. In the second and third examples, ANNs were developed with real-world hydrologic and climate data for different hydrogeologic environments. For the second problem, an ANN was developed using data collected for a 5-year, 8-month period to predict heads in a multilayered surficial and limestone aquifer system under variable pumping, state, and climate conditions. Using weekly stress periods, the ANN substantially outperformed a well-calibrated numerical flow model for the 71-day validation period, and provided insights into the effects of climate and pumping on water levels. For the third problem, an ANN was developed with data collected automatically over a 6-week period to predict hourly heads in 11 high-capacity public supply wells tapping a semiconfined bedrock aquifer and subject to large well-interference effects. Using hourly stress periods, the ANN accurately predicted heads for 24-hour periods in all public supply wells. These test cases demonstrate that the ANN technology can solve a variety of complex groundwater management problems and overcome many of the problems and limitations associated with traditional physically based flow models. 相似文献
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城市生态住宅小区分散式雨水人工湿地处理研究 总被引：3，自引：0，他引：3
以小区为单位的城市雨水分散式收集利用有利于减轻城市洪涝灾害,减小城市排水管网长度和管径,缓解城市供水压力,对改善城市水环境和生态环境具有重要意义。本文提出利用人工湿地处理小区地表径流并回用于城市地下水补给、绿化的思路,论述了城市雨水人工湿地再生处理利用系统中主要工艺的设计计算方法,为缓解城市用水压力提供有效途径。 相似文献
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Artificial neural networks and cluster analysis in landslide susceptibility zonation 总被引：14，自引：1，他引：13
A landslide susceptibility analysis is performed by means of Artificial Neural Network (ANN) and Cluster Analysis (CA). This kind of analysis is aimed at using ANNs to model the complex non linear relationships between mass movements and conditioning factors for susceptibility zonation, in order to identify unstable areas. The proposed method adopts CA to improve the selection of training, validation, and test records from data, managed within a Geographic Information System (GIS). In particular, we introduce a domain-specific distance measure in cluster formation. Clustering is used in data pre-processing to select non landslide records and is performed on the whole dataset, excluding the test set landslides. Susceptibility analysis is carried out by means of ANNs on the so-generated data and compared with the common strategy to select random non-landslide samples from pixels without landslides. The proposed method has been applied in the Brembilla Municipality, a landslide-prone area in the Southern Alps, Italy. The results show significant differences between the two sampling methods: the classification of the test set, previously separated and excluded from the training data, is always better when the non-landslide patterns are obtained using the proposed cluster sampling. The case study validates that, by means of a domain-specific distance measure in cluster formation, it is possible to introduce expert knowledge into the black-box modelling method, implemented by ANNs, to improve the predictive capability and the robustness of the models obtained. 相似文献
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Natural Resources Research - Blasting is the most popular method for rock fragmentation in open-pit mines. However, the side effects caused by blasting operations include ground vibration, air... 相似文献
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《The Journal of geography》2012,111(8):428-435
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通过对扎龙河漫滩湿地植被定位观测,对比研究人为补水对湿地植被的影响。人为补水后,湿地植被发生了湿生化演替趋势。湿草甸植物生活型谱中,地面芽植物有所增加,挺水植物沼泽则无明显变化;湿地与草地过渡带植物生活型组成对水位增加反应敏感,典型湿地植被生活型组成变化不大。研究表明,水位波动强烈的河漫滩湿地中,水文学的微弱改变可以导致湿地植被的明显变化。湿地的人为补水应结合准确的气候预测,进行湿地生态需水量研究,确定合理的补水量和补水时间。 相似文献
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Subjective geomorphic mapping is a method commonly used for landslide hazard zonation. This method relies heavily on the skills and experience of the mapper, and therefore, its major drawbacks are the high costs and lack of consistency between products generated by different terrain mappers. In this study a method for cost-effective and consistent replication of subjective geomorphic mappings is demonstrated, by using a type of Artificial Neural Network named Learning Vector Quantization. This paper presents a study conducted in the Canadian province of British Columbia employing a high-quality data set. By utilizing Learning Vector Quantization, stable and unstable terrains were delineated with a similarity of approximately 91%, compared to the mapping produced by terrain specialists. Also, in this process, slope, elevation, aspect, and existing geomorphic processes were identified as the terrain attributes that contributed most to the quality of the mapping. 相似文献
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利用吐哈盆地2011-2015年逐时FY-2E静止气象卫星红外云图资料,吐鲁番市1976-2015年5个国家气象站和2013-2015年26个区域气象站降水资料,采用卫星资料反演和统计分析方法,首次定义TK（地面气温与云顶亮温的差值）来规避地面辐射对卫星接收辐射的影响,分析吐鲁番盆地各级别TBB（-10~-20℃、-20~-30℃、-30~-40℃、-40~-50℃）云的分布状况及其与降水的关系、降水的时空分布特征和变化趋势。结果表明,吐鲁番盆地TBB各级别云覆盖度与海拔高度显著正相关,云量从盆地平原区向山区递增;TK的月变化同月降水具有较好的正相关性,TK正值时段4~8月与盆地汛期相对应,TK极大值对应月降水量最大的6月;降水与海拔高度显著正相关,降水先随海拔高度增加而增多,1 400~1 900 m区域是降水量和降水垂直变率最大的区域,之后降水随海拔高度增加而减少;降水高度集中在夏季与秋季,6月降水最多（占3~4成）;降水集中出现在白天,平原地区集中在早晨至中午,山区集中在下午至傍晚。综合分析得出吐鲁番盆地人工增水作业区域、作业月份、作业"时间窗"选择的参考依据,其中最佳作业区域在1 400~1 900 m,最佳作业月份为6月,最佳作业"时间窗"为上午的06~10时与下午的14~18时。 相似文献
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Laboratory simulation of the catagenesis of organic matter in sedimentary rocks has been used to provide an understanding of the processes involved in petroleum generation. Several of these studies have focused on the thermal evolution of organic matter (OM) present in Recent sediments. This study examines the geochemical characteristics and experimental thermal evolution of primary organic matter from two organic facies that are thought to be major contributors to Venezuelan hydrocarbon source rocks. A third facies, generally considered unimportant for petroleum formation, is used to contrast the experimental results. Hydrous pyrolysis maturation experiments were performed for three intermediate temperatures. The products of the final 330°C stage are shown in this paper because they best illustrate the changes in the OM during catagenesis. Results from the hydrous pyrolysis experiments show that at 280°C and higher all three samples yield liquid hydrocarbons similar in composition to natural crudes and the transformed organic matter is similar to kerogen that occurs in natural source rocks. Chromatograms from the saturated fraction of extracts at 330°C are similar to natural crudes with respect to n-alkane distribution and abundance of beta; and beta;alpha; hopanes. The only difference seems to be the relative abundance of 22R over 22S isomers, which indicates immature oil. This is in contrast to indications from the R
o and T
max parameters measured on the accompanying kerogen. 相似文献
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丹顶鹤越冬期在人工湿地的夜栖分布 总被引：1，自引：0，他引：1
在盐城国家级自然保护区人工湿地内,通过对丹顶鹤越冬期间夜栖地的调查,得出鹤群夜栖分布及其动态规律,并提出对该种群与夜栖地的管理措施。该项工作主要借助望远镜、GPS.照相机,采用直接计数法统计数量和利用文献资料数据。结果表明:人工湿地中丹顶鹤的夜栖分布随着环境的改变而改变,其中安全度和水位为其主要限制因子。因此控制人工湿地冬季水位,保护栖息环境不受人为影响是丹顶鹤安全越冬的主要保护措施。 相似文献
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针对江汉平原区堤垸人工微地貌,综合局部地形分析、水流模拟分析以及GIS空间分析和地统计分析方法,利用SRTM DEM数据进行微地貌自动提取研究。根据人工微地貌特点,构建一种局部地形形态分析方法来对结构线位置进行标示,并提出一种流域合并的方法来进行微地貌结构线提取;进而综合上述两种方法的计算结果,提出平原区人工微地貌的组合提取方法。研究结果表明该方法可较好实现平原区垸堤人工微地貌结构线提取。 相似文献