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1.
狗年,渐行渐远,悄无声息地离我们而去了。对于狗年“撞狗”运的驾驶人,感触可是酸甜苦辣什么都有,从车狗相撞不属交通事故到属于交通事故,是最分明的分水岭。  相似文献   
2.
约基台错救命水 8月7日,我们完成了巴毛穷宗的考察工作,全队拔营继续向北挺进。我们绕过几乎干涸的莲蓬湖,翻过一道缓平的分水岭来到了约基台错盆地,在这一盆地中分布着许多大小湖泊,显然都是约基台错退缩后留下的残遗水体。约基台错面积有26平方公里,是一个即将干涸的高度浓缩的盐湖。  相似文献   
3.
张鹏 《绿色视野》2012,(5):20-25
2012年3月1日,是个分水岭。这一天,备受关注的合肥市《机动车环保检验合格标志分类管理制度》正式实行。从当日起,新车可直接在环检机构内的环保窗口申领环保标志;排气检测不合格的在用车辆,将拿不到环保标志和安全技术检验合格标志,今后将无法上路。  相似文献   
4.
A case study is introduced and discussed concerning water dispute of misuse and pollution between up- and down-stream parts. The relations between water usage and local industrial structures are analyzed. Results show it is important to change industrial structures of the target region along with controlling water pollution by technical and engineering methods. Three manners of upstream-downstream cooperation are presented and discussed based on the actual conditions of Guangting Reservoir watershed. Two typical scenarios are supposed and studied along with the local plan on water resources development. The best solution for this cooperation presents a good way to help the upstream developing in a new pattern of eco-economy.  相似文献   
5.
本文对江淮分水岭地区的气候资源,水资源,农业生产结构进行了分析,对合理开发利用气候资源和水资源问题提出了一些措施。  相似文献   
6.
Streamwater chemistry and spatial flow dynamics from a subalpine Abies fabri forest in an experimental watershed located in the east slope of Gongga Mountain were analyzed to gain insights into the gradient effect of primary community succession on the stream biogeochemical process. Results showed that high sand content (exceeding 80%) and porosity in the soil(exceeding 20% in A horizon and 35% in B horizon), as well as a thick humus layer on the soil surface, made the water exchange quickly in the Huangbengliu (HBL) watershed. Consequently, no surface runoff was observed, and the stream discharge changed rapidly with the daily precipitation. The flow trends of base ions in the stream water were influenced by the Abies fabri succession gradient. Ca^2 , HCO3^- and SO4^2,- were the dominant anions in the streamwater in this region. A significant difference of Ca^2 , HCO3^- and SO4^2- concentration exported between the succession stages in the watershed can be found. But they had the similar temporal change in the stream flow. Ca^2 , HCO3^- and SO4^2- showed significantly negative correlations with the daily precipitation and the stream discharge. Concentrations of Cl^- , Na^ , K^ , and Mg^2 were low in all streamwaters monitored and we observed no differences along the Abies fabri succession gradient. Low ratios of Na. (Na Ca) (range from 0.1 to 0.2) implied cations were from bedrock weathering (internal source process in the soil system) in this region. But, a variance analysis showed there were almost no differences between rainwater and streamwaters for Mg^2 , Na^ , K^ , and Cl^- concentrations. This indicated that they might be come from rainfall inputs(external source). The highly mobile capacity, rapid water exchange between precipitation and discharge, and long-term export lead to this observed pattern were suggested.  相似文献   
7.
Sediment has been identified as a significant threat to water quality and channel clogging that in turn may lead to river flooding. With the increasing awareness of the impairment from sediment to water bodies in a watershed, identifying the locations of the major sediment sources and reducing the sediment through management practices will be important for an effective watershed management. The annualized agricultural non-point sourcepollution(AnnAGNPS) model and newly developed GIS interface for it were applied in a small agricultural watershed, Redrock Creek watershed, Kansas, in this pilot study for exploring the effectiveness of using this model as a management tool. The calibrated model appropriately simulated monthly runoff and sediment yield through the practices in this study and potentially suggested the ways of sediment reduction through evaluating the changes of land use and field operation in the model for the purpose of watershed management.  相似文献   
8.
传统影像分类方法多利用影像端元光谱进行地物分类,影像的空间结构信息被忽视,本研究结合面向对象分类方法思想以提高红树林遥感分类精度。本研究提出了一种结合端元类型选择、像元提纯等混合像元分解手段及分水岭图像分割算法的改进光谱角影像分类方法,并以山口红树林国家级自然保护区为研究区,利用GF-1号遥感影像数据,在光谱特征分析和地面调查的基础上,对红树林生态系统进行分类,并对分类精度进行分析。研究结果表明:改进的光谱角分类方法对GF-1影像分类效果较好,既兼顾地类光谱组成较复杂时的特殊性,又有效避免结果的破碎化现象,且总体精度达到95%(KAPPA系数0.944),证明了其在红树林遥感影像分类及信息提取方面的应用潜力,为红树林生态系统业务化遥感监测奠定了基础。  相似文献   
9.
八百里巢湖,号称"皖中明珠",自汉代起就是我国重要的粮食产区。历经数千年的沧桑,受巢湖恩泽的人们日渐富庶,然而巢湖的容颜却在一天天老去、蜕变。2012年对于巢湖来说是个分水岭。这一年,巢湖管理局正式挂牌,结束"多头"管理。这一年,已实施近14年的《巢湖流域水污染防治条例》再次大修。这一年,合肥的"大湖名城"之梦正在编织……诸多事件表明,古老的巢湖正在发生着历史性的嬗变。  相似文献   
10.
<正>联合国环境规划署最新报告表明,与利用煤炭和石油发电的1100亿美元投资相比,2008年全球绿色能源发电的投资首次超过传统能源,达到了1400亿美元。低碳经济中的最重要领域——绿色能源(太阳能、风能、生物能源等)发展的状况表明,全球低碳经济发展已进入一个重要分水岭,它已开始对各国经济结构,投资和生产生活产生重要影响。  相似文献   
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