Application of PPE Model in Land Adaptability Appraisal in Small Basin Based on RAGA

The paper applies multi-dimension to lower technology-projection pursuit evaluation model in the conservation of water and soil discipline domain, optimizes the projection direction using the improved acceleration genetic algorithms, transforms the multi-dimensional data target to lower sub-space, and values soil adaptability of Dongdagou basin in Keshan County by searching the optimal projection direction and the projection function data. The paper provides a new notion and method for the conservation of water and soil in small basin.

RESEARCH ON SYSTEM OF FLOOD DISASTER CONTROL AND REDUCTION SUPPORTED BY GIS IN MEDIUM AND SMALL BASINS

Southeast China coastal areas belong to subtropical monsoon climatic zone, thus easily affected by floods resulted from typhoons and rainstorms. Since the areas of river basins are small, rivers flood regulation capacities are low, and therefore flood hazard is grave. In this paper, taking the Yongjiang basin in southeast China as an example, the approaches and methods of geographic information system(GIS) applied to flood disaster control and reduction research on small basin are explored. On GIS help the rainfall runoff calculation model and the river channel flood routing model are developed. And the evaluating flood submerged area and the damage assessment models are built supported by digit elevation models. Lastly the decision support system on GIS supported for flood control in research basin has been set up. This greatly improves flood proofing decision making capacities in river basin, and provides valuable information and a mode for flood prevention and reduction in the medium and small basin. Meanwhile, the research indicates that technologies of GIS provide a powerful tool for flood disaster control.

Early Palaeozoic Evolution of the Zhen' an- Xichuan Block and the Small Qinling Multi-Island Ocean Basin

Based on studies of palaeogeography, palaeobiogeography, palaeomagnetism, geochemistry and volcanism, this paper proposes that the Zhen'an-Xichuan area was a small Early Palaeozoic block rifted away from South Qinling and suturing onto North Qinling earlier than the other parts of South Qinling. In the Early Palaeozoic Qinling was a small archipelagic ocean basin with 5 rows of islands including the Zhen'an-Xichuan block. The drifting of the Yangtze and North China plates and the islands between them in the same direction at different speeds caused their suturing process to be different from the classic plate collision, which is the major feature of the suturing of the multi-island Tethys ocean basin. This also explains the problem that the Caledonian collision did not result in orogeny in eastern Qinling.

Problems for water resources development in typical small karst drainage basins and countermeasures

In karst area water deficit is one of the main factors constraining sustainable economic development. In 1979 the comprehensive karstic observational field station was set up in Houzhai drainage basin located,\ in Puding county of Guizhou Province, which can represent most of the small karst drainage basins on the dividing line of the Guizhou Plateau. Geomorphology, water resources and water chemistry were investigated and observed. Based on comparisons of water supply with water demand and analysis of the main problems in water exploitation and utilization. it is found out that the water deficiency was not directly caused by the scarcity of natural water resources. The true reason is the insufficient capacity of water supply caused by the dismatch of the water and soil water resources which can be dealt with by building more irrigation works. Some solutions such as to build scientific basis for water exploitation and utilization and sustainable economic development in karst drainage basins on dividing line of the Guizhou Plateau.

Analysis on Hydrological Regimes of the Medium and Small Rivers in Hami of Xinjiang——Take Toudaogou Basin as an Example

[ Objective] The research aimed to analyze hydrological regimes of the medium and small rivers in Hami of Xinjiang. [ Method] According to actual observation data at Toudaogou hydrological station during 1956 -2010, climate, runoff, flood, sediment and water quality in the basin were analyzed. [ Result] Runoff in Toudaogou River was mainly from bedrock fissure water and rainfall, and depended on temperature and precipi- tation in the catchment zone. Runoff in Toudaogou River had very big change during the year. Runoff in whole year mainly concentrated during April -June, which occupied 57.9% of annual runoff. Flood in Toudaogou basin was divided into spring and summer flood from time, and snowmelt and rainstorm flood from type. Sediment load was related to terrain, gradient, runoff, precipitation, flood and process. Suspended sediment load at Toudaogou hydrological station had close relationship with the annual maximum flow capacity of flood peak, and related coefficient was 0.917. [ Conclusion] Hydrological regime in Toudaogou basin basically represented corresponding hydrological information of rivers without glacier water supply in Hami even whole western arid zone of China. The research could provide theoretical basis for scientifically using water resources of the medium and small rivers in the zone.

One feature of the activated southern Ordos block:the Ziwuling small earthquake cluster

Small earthquakes （Ms〉2.0） have been recorded from 1970 to the present day and reveal a significant diffrence in seismicity between the stable Ordos block and its active surrounding area. The southern Ordos block is a conspicuous small earthquake belt clustered and isolated along the NNW direction and extends to the inner stable Ordos block; no active fault can match this small earthquake cluster. In this paper, we analyze the dynamic mechanism of this small earthquake cluster based on the GPS velocity field （from 1999 to 2007） , which are mainly from Crustal Movement Observation Network of China （CMONOC） with respect to the north and south China blocks. The principal direction of strain rate field, the expansion ratefield, the maximum shear strain rate, and the rotation rate were constrained using the GPS velocity field. The results show that the velocity field, which is bounded by the small earthquake cluster from Tongchuan to Weinan, differs from the strain rate field, and the crustal deformation is left-lateral shear. This left-lateral shear belt not only spatially coincides with the Neo-tectonic belt in the Weihe Basin but also with the NNW small earthquake cluster （the Ziwuling small earthquake cluster）. Based on these studies, we speculate that the NNW small earthquake cluster is caused by left-lateral shear slip, which is prone to strain accumulation. When the strain releases along the weak zone of structure, small earthquakes diffuse within its upper crust. The maximum principal compression stress direction changed from NE-SW to NEE-SWW, and the former reverse faults in the southwestern margin of the Ordos block became a left-lateral strike slip due to readjustment of the tectonic stress field after the middle Pleistocene. The NNW Neo-tectonie belt in the Weihe Basin, the different movement character of the inner Weihe Basin （which was demonstrated through GPS measurements） anti the small earthquake cluster belt reflect the activated southern margin of the Ordos block, which was generated through readjustment of the tectonic stress field after the middle Pleistocene.

ANALYSIS OF ECONOMIC EFFICIENCY OF SMALL VALLEY’S COMPREHENSIVE TREATMENT OF HUANGJIA-ERCHA IN XIJI COUNTY,NINGXIA

The Lanni River, rising at Laojunpo, Huining County, Gansu Province, entersNingxia at Libaocun, Sanhexiang, Xiji County. It flows through 10 villages and joints theHulu River at Gongyixiang, Xiji County and finally flows through the Wei River into theYellow River. The section of the river within Xiji County is 44.8 km long with a

小型含油气盆地成因类型、特征与油气赋存

沉积盆地分布广、数量多,其中小型盆地数量占比居多。中国小型盆地占全国盆地总数的80%以上,虽然发现工业油气藏的小型盆地占比少于10%,远低于大—较大型盆地(>76%),但是小型含油气盆地的油气丰度(HAPUA)大多较高,“小而富”盆地远高于多数大中型含油气盆地,勘探成效较高。通过对中国16个含常规油气小型盆地的综合研究,根据盆地形成机制和动力环境的差异,将其分为残留型和原始型两大类型;进一步将后者细分为走滑、裂陷和热力成因3类。小型残留成因含油气盆地一般经历了主力烃源岩形成的原盆建造、后期改造残留和晚期覆埋生烃的演变时段,3期缺一不可。其中原盆中部分烃源岩得以残留奠定了资源基础,晚期深埋是烃源岩成烃-聚集并成藏的关键环节。原始小型含油气盆地中的走滑、裂陷和热力3种成因类型,均在较活动的动力环境中形成演化,一般具有较快沉降-沉积、较高地温场、活跃的深部背景和晚(后)期改造等特征。这类动力环境使盆地沉积了“小而厚”的地层并形成多种形式的构造圈闭,有利于生物超常勃发繁盛和优质烃源岩形成及生烃转化,有助于油气聚集成藏。盆地油气“小而富”与“小岩体成大矿”,在形成动力环境和成矿理论认识等方面有相通之处。这两大领域在科学研究和学术思想等方面可触类旁通、相互借鉴参考。

数字素养对小农户衔接现代农业的影响研究——基于黄河流域9省区1592户小农户的调查

基于黄河流域9省区1592户小农户的调研数据,利用LPM和Probit模型分析数字素养对小农户衔接现代农业的影响。结果表明:数字素养的提升能够促进小农户衔接现代农业;机制分析发现,数字素养通过拓宽小农户信息获取渠道、提高小农户信息获取能力来影响小农户衔接现代农业;引入ESRM模型结合反事实推断分析发现,数字素养提升可以使小农户衔接现代农业的水平提高45.33%;小农户数字素养对地理邻近农户衔接现代农业的行为具有正向空间溢出效应;异质性检验发现,数字素养对衔接现代农业的影响在纯小农户中最大,其次是兼业型小农户,数字素养对中低收入小农户衔接现代农业的影响要大于高收入小农户。根据结论,提出加强对小农户的数字化培训和指导以提升其数字素养,对不同类型小农户有针对性地提供帮扶措施,通过示范效应带动周边小农户衔接现代农业等政策建议。

沿海中小河流域地表-地下水库联合调控洪水资源利用研究:Ⅰ.方法与模型

针对沿海中小河流域地表-地下水库复杂工程系统,因缺少联合调控方法而导致洪水资源利用难的问题,解析地表-地下水库系统结构与功能,定量模拟地表水库调度、闸坝调控下河流和地下水动力过程,并利用智能替代模型提升水动力过程计算速度;在此基础上通过研发时/日/月多时间尺度模型耦合嵌套方法,构建了兼顾计算精度与效率的地表-地下水库联合调控模型。该模型实现了洪水、地表-地下水相互作用和供水等时间尺度差异明显的调节过程的统一调配,可为沿海中小河流域洪水资源利用提供新思路与技术支撑。

西南丘陵地区小流域土地利用格局与生态环境变化规律研究

土地利用格局变化与人类的实践活动与自然演变息息相关,对人与自然和谐共生具有重要的意义。选取西南丘陵地区小流域—琼江流域内的遂宁市安居区为研究对象,通过遥感技术和地理信息系统,结合土地利用转移矩阵,研究了遂宁市安居区土地利用格局与生态环境变化规律。结果表明:2010—2019年间安居区土地利用变化速度整体呈先增加后变缓的趋势,城镇用地变化显著,主要由耕地转化而来;安居区城镇用地土地利用动态度较大,其他4类土地利用类型变化较小;10年间安居区土地利用程度综合指数呈上升趋势,土地开发利用强度增大,但总体上升平缓;2010—2019年间安居区生态环境质量逐渐下降,林地、耕地面积减少为主要原因。本研究成果可为我国西南小流域城镇土地利用规划和可持续发展提供借鉴与参考。

鄂尔多斯盆地DND气田马家沟组马五段小层划分探析

鄂尔多斯盆地DND气田中奥陶统马家沟组自下而上划分为6段,其中马五段是该气田下古生界主要产气层,随着对DND气田马五段气藏的开发力度不断加大,马五6-马五10亚段的小层精细划分已日益迫切。为此在继承鄂尔多斯盆地中东部马五1-马五5亚段小层成熟划分方案的基础上,利用岩心、薄片、录井、测井资料针对研究区136口井的马五段尤其是马五6、马五7亚段进行亚段及小层的精细划分,寻找并确定标志层,利用对碳酸盐岩岩性敏感的光电吸收截面指数曲线区分石灰岩与白云岩地层,将自然伽马、自然电位、声波时差等多种测井响应结合识别碳酸盐岩岩性段。研究表明:目前可将马家沟组马五段划分出10个亚段和21个小层;马五6亚段“四分”,厚度范围为4.6~13.3 m,平均值8.8 m;马五7亚段“三分”,厚度范围为5.9~15.3 m,平均值9.8 m。马五6、马五7亚段小层精细划分在鄂尔多斯盆地尚属首次,将为DND气田及其他气田的马家沟组中组合气藏小层划分提供重要参考。

地铁车站狭长基坑支撑异常轴力分析

【目的】研究地铁车站狭长型基坑施工过程中第一道支撑轴力过大的问题。【方法】通过土体小应变刚度硬化模型(HSS)有限元分析,对车站基坑土方的开挖方式、钢支撑安装质量差、钢支撑未及时受力等情况进行精细化模拟,分析其对第一道支撑轴力的影响。【结果】结果表明:采用盆式开挖对第一道支撑的轴力影响显著,相较分层开挖的情况增大45%,应及时安装对应位置的钢支撑;安装钢支撑的预应力未达到设计值时,会导致开挖到底时的顶层支撑轴力增大,增大幅度在10%以内,底层支撑轴力减小。【结论】在地铁车站狭长基坑开挖过程中应限制盆式超挖;温度变化对支撑轴力的影响不能忽视;安装下层钢支撑预应力达不到设计值时,会导致开挖到底时的顶部支撑轴力偏大。

滇池流域河道生态补偿机制成效评价与完善对策

2017年4月起实施的昆明市滇池流域河道生态补偿机制,为市级层面小流域生态补偿机制的建立和实施提供了先行先试经验。为充分发挥生态补偿机制对河道水质改善的促进作用,采用定性定量相结合的方法,分析了昆明市滇池流域河道生态补偿机制建设运行情况和水环境改善效益,评估该机制的有效性,总结成效与存在的问题,提出机制完善的对策建议。研究表明:滇池流域河道生态补偿机制实施以来,河湖水环境明显改善、水质监测网络逐步健全、水环境管理能力明显提升,机制总体有效,但也还存在考核指标待优化、补偿范围不全面、补偿方式单一、监管评估和公众参与有待加强等问题,需要进一步完善补偿机制,多渠道筹集补偿资金,健全生态补偿绩效评价制度,促进形成可复制可推广的滇池流域生态补偿模式。

基于安德森模型的洱海流域小农户养老方式选择偏好及影响因素研究

为探索洱海流域小农户养老方式的选择偏好及影响因素,采用多阶段随机抽样方法抽取洱海流域40岁以上的村民290位,进行问卷调查获取数据;基于286份有效问卷运用卡方检验和二元Logistic回归,从40岁以上人员对养老相关问题的看法,分析小农户养老方式选择偏好的差异;以安德森行为模型为理论框架,探究倾向性因素、使能因素、需求性因素对洱海流域小农户养老方式选择偏好的影响。结果显示:洱海流域小农户目前以家庭养老作为主要的养老方式,倾向性因素是养老方式选择偏好最主要的影响因素,需求性因素次之。建议多方主体积极引导当地农户转变传统的养老观念,积极探索适合当地小农户的多元的养老方式,加大养老工作方面资金的投入力度。

四川盆地中部地区震旦系大型碳酸盐岩气藏开发技术新进展

四川盆地中部地区(以下简称川中地区)震旦系灯影组气藏为大型古老深层岩溶风化壳型碳酸盐岩气藏,气藏整体表现为低孔隙度低渗透率,储集空间小尺度缝洞发育,储层非均质性强特征,气藏开发面临储层表征难、井位部署和效益开发难度大等系列挑战。为此,以川中地区安岳气田灯影组气藏为对象,通过地质工程一体技术化攻关,深化了对储层发育特征和成因机理的认识,提出了气藏开发新模式,创建形成了气藏高效开发的关键技术。研究结果表明:①灯影组储层主要为岩溶成因储层,具有“叠合岩溶差异控储”的发育特征;②岩溶储层非均质性强,“溶蚀相成因控储”可精细刻画储层的非均质性;③灯影组气藏宜采用“单井指标叠加论证气藏规模”的开发新模式;④创新形成了“双界面”岩溶古地貌恢复及定量刻画方法,并指导平面选区,其中Ⅰ+Ⅱ类井比例由评价期的40%提高到方案建设期的100%;⑤创建了小尺度缝洞识别、刻画及表征技术,并指导钻井轨迹设计,测试百万立方米气井比例由开发评价期的41.6%提高到建产期的60%;⑥配套完善了分段酸压工艺技术,高效动用了优质储层,并解放了低品位储层,储层渗透率由改造前的0.62 mD提高到酸压改造后的6.77 mD。结论认为,“十四五”期间,在上述开发技术的支持下,安岳气田由台缘带灯四段高效开发转向长期稳产和台内地区多层系效益开发,蓬莱含气区由单井高产转向区块高产和气藏规模建产,将强力支撑中国石油西南油气田公司“十四五”末天然气上产500×10^(8)m^(3)。

小河流域水库储水变化及评估研究

为了填补中国水库分布和蓄水情况的信息空白,编制了某小河流域的水库清单,并利用遥感观测估计了2000年和2018年水库的季节性储水量变化。研究区域包括149个水库,其中102个为2000年之前建造的现有水库,另外47个为2000年至2018年期间新建的水库。利用中分辨率成像光谱仪(MODIS)的表面反射率数据对水库进行监测,通过分析归一化差异水体指数(NDWI)时间序列来检测水库的存在。为了估计所有水库的储水变化,结合了谷歌地球引擎(GEE)平台上检索到的水库淹没范围和航天飞机雷达地形任务DEM数据中获取的海岸线地形信息。通过这项研究,能够更全面地了解某小河流域水库的分布情况和季节性储水量变化。

香山河小流域水文特性初步分析

以武鸣河支流香山河为例,通过统计香山河流域内的降雨、蒸发、水位、流量、径流等水文观测资料并结合场次洪水分析降雨蒸发关系、降雨径流关系、洪峰水位关系等,初步总结香山河小流域水文规律,尝试探究中小河流流域水文特性研究方法,并提出相应的水文测验工作建议。

红原县白河瓦切镇塔林段水生态保护方案之浅见

黄河上游高寒草甸草原小流域生态环境脆弱,部分小流域因受过度放牧、草皮层冻融剥离、河水冲刷等因素影响出现了河流两岸草甸退化、水土流失严重、水源涵养能力降低等现象。阐述了针对该区域小流域出现的上述水生态环境问题进行的研究,结合阿坝州红原县黄河流域白河瓦切镇塔林段水生态保护项目,提出了“草甸修复、生态护岸、封禁治理、湿地建设、水污染防治”的综合治理思路,并给出了相应的治理方案。该方案落实后,可以起到在维持该地区原有生态景观的同时修复河流两岸受损草原的生态系统,改善水环境质量,提高当地小流域水土保持及水源涵养能力的作用。

基于气象水文耦合的水库实时洪水预报方法

以水库实时洪水预报为研究对象,针对中小流域预见期短,流域天然预见期难以满足水利工程生产要求的问题,研究水库实时洪水预报方法,构建基于气象水文耦合的水库实时洪水预报模型。首先,采用短时临近外推技术及STMAS-WAF中尺度天气模式,建立24 h降水预报模型;然后将气象预报成果耦合至水文预报,实现气象水文的时空尺度匹配;最后建立基于来水预报成果反馈的降水预报修正方法,根据前期规律滚动修正未来24 h降水预报成果,将修正后的降水预报输入水文模型,实时预测水库来水,使水文模型从源头上实现准确输入,实现高精度长预见期的水库实时洪水预报,解决了传统水文模型预见期不足的问题。以新安江水库为例开展了模型的实例研究,编制新安江水库气象水文耦合预报方案,进行水库实时洪水预报,并探讨不同降雨输入形式对预报精度的影响,研究结果表明:基于气象水文耦合的水库实时洪水预报方法考虑了气象水文的双向反馈,将新安江水库实时洪水预报预见期从6 h左右提升至18 h,确保18 h预见期内预报精度在80%以上。与不考虑降水预报及使用未修正降水预报的2种传统方法的有效预见期相比,新方法的有效预见期分别提升了200%和29%,有效延长了水库实时洪水预报预见期,提高了洪水预报服务能力,给水库实时洪水预报提供了一种行之有效的方法。