Geochemistry of borehole cutting shale and natural gas accumulation in the deepwater area of the Zhujiang River Mouth-Qiongdongnan Basin in the northern South China Sea

The Qiongdongnan Basin and Zhujiang River（Pearl River） Mouth Basin, important petroliferous basins in the northern South China Sea, contain abundant oil and gas resource. In this study, on basis of discussing impact of oil-base mud on TOC content and Rock-Eval parameters of cutting shale samples, the authors did comprehensive analysis of source rock quality, thermal evolution and control effect of source rock in gas accumulation of the Qiongdongnan and the Zhujiang River Mouth Basins. The contrast analysis of TOC contents and Rock-Eval parameters before and after extraction for cutting shale samples indicates that except for a weaker impact on Rock-Eval parameter S2, oil-base mud has certain impact on Rock-Eval S1, Tmax and TOC contents. When concerning oil-base mud influence on source rock geochemistry parameters, the shales in the Yacheng/Enping,Lingshui/Zhuhai and Sanya/Zhuhai Formations have mainly Type Ⅱ and Ⅲ organic matter with better gas potential and oil potential. The thermal evolution analysis suggests that the depth interval of the oil window is between 3 000 m and 5 000 m. Source rocks in the deepwater area have generated abundant gas mainly due to the late stage of the oil window and the high-supper mature stage. Gas reservoir formation condition analysis made clear that the source rock is the primary factor and fault is a necessary condition for gas accumulation. Spatial coupling of source, fault and reservoir is essential for gas accumulation and the inside of hydrocarbon-generating sag is future potential gas exploration area.

Characteristics and Optimization of Distribution of Rural Residential Area in Wangcun River Basin of Linfen City

As a carrier of rural population,rural residential area carries important functions such as rural production and life. This paper studied the characteristics of rural residential area and optimization model,to lay certain foundation for integrating urban and rural development and increasing economic income. With the aid of Arc GIS 10. 1 and Fragstats 3. 4 software,based on the theory of landscape ecology,it analyzed the distribution characteristics of residential area in Wangcun River Basin of Anze County,Linrfen City,Shanxi Province. Besides,according to distribution characteristics,it analyzed three optimization models: priority development model,retention limit development model,and migration development model.

Surface Temperature Anomalies in the River Niger Basin Development Authority Areas, Nigeria

The study investigates the trends in temperature in the Upper and Lower Niger Basin Development Authority Areas using standardized Anomaly Index, Gaussian Low Pass and Spearman’s correlation coefficient. From the data collected and analyzed, the mean annual temperature and mean annual maximum temperature demonstrated pronounced temporal increasing trend in the period 1951-2010 while the mean annual minimum temperature showed no trend. The rate of increase in mean annual temperature, mean annual maximum and minimum temperatures was 0.45°C, 0.40°C and 0.20°C respectively. The mean annual maximum temperature warmed faster than the mean annual minimum leading to increase in diurnal range of temperature. The annual temperature anomaly in the study area tracks the observed anomalies for the Northern Hemisphere in the 20th century. The decadal temperature increase is very small particularly as from 1980.

Variability and Trends of Daily Heavy Rainfall Events over Niger River Basin Development Authority Area in Nigeria

Using 70 years of daily rainfall records in eight stations, an analysis of variability and trends of daily heavy rainfall events over Niger River Basin Development Authority Area was carried out by using Standardized Anomaly Index and Spearman Rank Correlation Coefficient. Significant temporal variability on interannual and decadal time-scales was observed in the frequency of heavy rainfall events and annual heavy rainfall amount. Both the annual heavy rainfall amount and frequency of heavy rainfall events demonstrated no pronounced temporal decreasing or increasing trend. However, more recent data records from 1981 onwards revealed an increasing trend. Thus, evidence of a temporal change is apparent in heavy rainfall events in the last three decades in sympathy with global warming.

The Process of Cultivated Land and Water Resource Distribution Changing in Recent Decades in Upstream and Downstream in Shiyang Inland River Basin in Arid Area of Northwest China

Last century 50 - 70 years, the dam construction of Shiyang Inland River Basin (SIRB) profound impact on the distribution of water resources and arable land in the basin. Through data collection, field surveys and remote sensing image interpretation, we analysis the use of land and water resources change process in the middle and lower reaches of SIRB in recent decades. The results show: (1) The cultivated area of SIRB has been an upward trend in recent decades, The whole basin cultivated area has increased total 229,000 hm2 from 1973 to 2010 and mainly in the middle and lower reaches. Midstream increased by 149,700 hm2 accounting for 65.36 percent of total, downstream increased by 70,000 hm2 accounting for 30.70 percent of total. (2) The amount of surface water resources of downstream reduce significantly gradually since dam construction, and the water table sharp decline. While the volume of surface water resources come downstream from the 1950s accounted for 30 to 40 percent of the total gradually reduced to less than 10% in 2012;(3) since the arable land area of middle and lower reaches of SIRB basin substantial increase, so the surface water resource does not meet irrigation needs. Agricultural irrigation relies heavily on exploitation of groundwater to supplement, resulting in Regional Groundwater Depth dropped rapidly, and forming several huge funnel groundwater settlements. 20 years from 1981 to 2001 the groundwater level of midstream dropped from around 5m to around 10m in Wuwei, and in Minqin dam-region of downstream along faster rate of decline in 20 years fell from 8.52 m to 22.68 m. Dam construction project has changed the pattern of the basin water cycle, the middle reaches closure a large number of surface water resources led to downstream sharp decline. Downstream continued exploitation of groundwater formed a few huge funnel groundwater settlements, it caused serious ecological problems. The basin should adjust the industrial structure and develop water saving irrigation, promote a virtuous cycle of water resources, to achieve sustainable development, seek a sustainable development ways conversion natural oasis to artificial oasis efficiency in arid zone.

Regional Evaluations of the Meteorological Drought Characteristics across the Pearl River Basin, China

Regional evaluation of drought characteristics provides critical information for water resource management. In this case, this study attempts to analyze the probability behaviors of drought events of a given severity in the Pearl River Basin and to construct severity-area-frequency curves of drought events. Due to possible impacts of complicated topographical properties and diverse climate types within the Pearl River Basin, the entire Pearl River Basin is subdivided into different homogeneous regions. In general, the Pearl River Basin can be categorized into four homogeneous regions, and the severity-area-frequency analysis results for the short-, medium- and long-term drought episodes within each homogeneous regions indicate stressful challenge for the water resource management in the Pearl River Basin due to the fact that severe droughts usually occur over the entire Pearl River Basin. Meanwhile, the Pearl River Delta will face a higher risk of drought when compared to other regions of the Pearl River Basin in terms of the medium-term drought. The Pearl River Basin is highly economically development and is heavily populated, thus impacts of droughts and related resilience resolutions or policies should be taken into account in the formulation of regional sustainable development of water resources and socio-economy within the Pearl River Basin, China.

Land Cover Change in the Barekese River Basin of Ghana

The Barekese reservoir provides 80 percent of the total public pipe borne water to the Kumasi metropolis and its environs.However,over the past two decades, the Barekese river basin has seen persistent degradation through anthropogenic activities along its catchment area which also raises concern on the deteriorating water quality.The study examines

面向城市群的黄河流域生态脆弱性研究

黄河流域是我国重要的生态屏障,其生态保护和高质量发展是重大国家战略,需要充分发挥城市群的引领作用。然而黄河流域上下游自然生态禀赋的差异和发展不平衡,以及各城市群之间协同合作不足,制约流域高质量发展。本文基于敏感-弹性-压力(SRP)模型和空间主成分法(SPCA)法构建黄河流域城市群生态脆弱性评价体系,对2020年山东半岛城市群、中原城市群、关中平原城市群、黄河“几”字弯都市圈和兰州-西宁城市群的生态脆弱性进行定量评估;同时基于层次聚类方法,对全域613个县域进行生态脆弱性区划,并探究人为活动对生态脆弱性的影响。结果表明:①2020年黄河流域城市群的生态脆弱性程度较高,平均值达到0.53,生态弹性是生态脆弱性的首要因子,权重为0.55。②在空间上,黄河流域城市群以中度脆弱区为主,面积占比为64.08%。③人为活动对生态脆弱性具有广泛影响,全域76.02%的县域表现出人为活动与生态脆弱性的显著相关性(P<0.05)。④研究确定了8种生态脆弱型,从空间分布来看,中东部农业敏感型地区的面积占比最大,为30.40%,而中心城区脆弱型和矿业脆弱型地区的面积占比最小,分别为0.37%和0.25%。研究显示,黄河流域各城市群的生态脆弱度不同,生态脆弱度最高的是山东半岛城市群和黄河“几”字弯都市圈,建议采取针对性的空间布局优化和生态修复措施,推进城市群的可持续发展。

干旱区自然资源地表基质细化分类体系构建与调查深度

地表基质分类是开展地表基质调查监测的基础,同时也是揭示地表基质与地表覆盖层的协同耦合关系的关键,有助于从地表覆被和地下空间要素两个层次认识地表基质与生态环境的作用机制。本研究以干旱区典型的内陆河流域——新疆三工河流域为靶区,依据干旱区山地-绿洲-荒漠景观异质性分布特征,在地表基质的分布区域、海拔范围及主要地表覆被的基础上,构建了一套地表基质三级分类分区体系。整体划分为4个地表基质一级类、17个二级类及28个三级类。根据土壤理化性质及植被根系分布特征,地表基质调查深度在南部山区以50 cm;中部平原区以3 m;北部沙漠区小于10 m为宜。此外,基于垂直带生态系统NPP的分异性特征,验证了分类体系的合理性,体现了地表基质层孕育支撑土地覆被的作用关系。研究成果为未来干旱区自然资源调查监测和科学管理决策提供理论与技术支撑。

基于ELECTREⅢ的湟水流域水资源可持续利用能力评价

水资源可持续利用能力研究对中国西北缺水地区实现水资源可持续管理和发展具有十分重要的意义。根据湟水流域特征,从气候因素、水资源系统和社会经济3个方面构建了水资源可持续利用能力评价指标体系,并引入ELECTREⅢ评价法评价了湟水流域水资源可持续利用能力状况。结果表明:湟水流域水资源的整体可持续利用能力为中等水平;气候因素和社会经济特征是影响湟水流域水资源可持续利用能力的主要因素。为提高湟水流域水资源可持续利用能力,应加强流域水资源综合管理、推进外流域调水、加强流域节水和非常规水资源利用和加强河流水环境综合整治等。研究成果可为缺水地区水资源可持续利用能力评价和优化流域水资源管理提供参考。

基于Flood Area模型的邢台市小马河流域暴雨洪涝灾害风险分布特征

利用邢台市小马河流域26个区域站2014—2019年及周边7个国家站1980—2019年的逐日降水资料,基于泰森多边形法和MuDFiT软件计算不同重现期面雨量。运行Flood Area模型对该流域不同重现期下的淹没范围进行模拟,基于此叠加承灾体数据,得到各承灾体受损率。为验证模拟结果的准确性,选取2016年7月19—20日强降雨过程对百年一遇暴雨洪涝灾害风险分布特征进行验证,结果与模拟淹没范围基本一致。研究表明随着重现期不断增大,洪水逐渐向中下游地区推进,淹没范围不断扩大加深。当淹没深度在0.1~0.3 m及1.0 m以上时,林地受损率最高,淹没深度小于0.1 m时,林地受损率最低。人口、GDP、城镇用地、耕地、草地等其他承灾体淹没深度在0.1 m以下时受损率最高,在0.1~0.3 m时受损率次之,在1.0 m以上时受损率居中,在0.3~0.5 m时受损率较低,淹没深度位于0.5~1.0 m时受损率最低。

A cultivated area forecasting approach in artificial oases under climate change and human activities

The cultivated area in artificial oases is deeply influenced by global climate change and human activities.Thus,forecasting cultivated area in artificial oases under climate change and human activities is of great significance.In this study,an approach named GD-HM-PSWROAM,consisting of general circulation model downscaling(GD),hydrological model(HM),and planting structure and water resource optimal allocation model(PSWROAM),was developed and applied in the irrigation district of the Manas River Basin in Xinjiang Uygur Autonomous Region of China to forecast the cultivated area tendency.Furthermore,the catchment export of the MIKE11 HD/NAM model was set to the Kensiwate hydrological station.The results show that the downscaling effects of temperature can be fairly satisfying,while those of precipitation may be not satisfying but acceptable.Simulation capacity of the MIKE11 HD/NAM model on the discharge in the Kensiwate hydrological station can meet the requirements of running the PSWROAM.The accuracy of the PSWROAM indicated that this model can perform well in predicting the change of cultivated area at the decadal scale.The cultivated area in the Manas River Basin under current human activities may be generally decreasing due to the climate change.But the adverse effects of climate change can be weakened or even eliminated through positive human activities.The cultivated area in the Manas River Basin may even be increasing under assumed human activities and future climate scenarios.The effects of human activities in the future can be generally predicted and quantified according to the cultivated area trends under current human activities and the situations in the study area.Overall,it is rational and acceptable to forecast the cultivated area tendency in artificial oases under future climate change and human activities through the GD-HM-PSWROAM approach.

数字孪生淠河建设实践与思考

数字孪生淠河根据淠河流域特征,以流域防洪需求为牵引,提出技术解决方案。在共享安徽省现有数据感知、网络传输、算力环境等基础上,建设内容包括流域数据底板、水利模型平台、水利知识平台等支撑平台,以及在上述支撑平台基础上建立防洪预报、预警、预演、预案“四预”应用。防洪“四预”应用以精细化洪水预报为预警、调度提供基础,洪水预警为下游圩区等保护对象提供多阶段预警,情景化洪水预演以实景化方式分析洪水影响,智能化方案实现防洪预案的快速、自动化生成。通过总结数字孪生淠河建设内容,进一步探讨数字孪生流域建设中存在的难点问题,为相关数字孪生流域建设提供借鉴。

砒砂岩区生态治理-生态衍生产业协同发展关键技术与模式

探索生态治理与生态衍生产业协同发展的关键技术与途径,是促进水土保持生态治理高质量发展的重要课题。为此,以生态治理难度极大的黄河流域砒砂岩区为研究对象,基于生态经济学、生态产业技术的理论与方法,提出了生态治理-生态衍生产业协同发展的基本原理和应遵循的原则,探索了生态治理与生态衍生产业协同发展的关键技术与模式,并开展了示范应用。1)生态治理-生态衍生产业协同发展的原理是行为互驱动、效应互补偿,应遵循的原则是“双律适应、适地适生、三方意愿”;2)鉴于砒砂岩覆土区、覆沙区、裸露区生态环境有明显差异,分别构建了小流域生态治理-生态衍生产业协同发展的综合治理措施体系和模式,以坡顶、坡面和沟道为水土保持措施配置的3个地貌单元,选择兼具水土保持功能和饲用、药用、食用等经济开发价值的作物进行生物措施配置,配合注浆固结、抗蚀促生、砒砂岩改性等新的工程技术措施进行生态治理;3)研发了物理-化学-生物综合改良砒砂岩土壤、砒砂岩复配风沙土+生物改良提质、灌草优化平茬及饲料加工、煤矸石改性资源化利用、高陡边坡抗蚀+控渗+植生固稳、生态果园建植等关键技术;4)基于砒砂岩覆沙区“土壤改良固沙+”(如土壤改良固沙+经济林种植、土壤改良固沙+梭梭草套种甘草等)生态治理模式的实践与示范,探索实施了“政府支持,科技支撑,企业产业化+公益性投资,农牧民市场化参与”的多元投资、多方参与、共同受益运行机制与模式。通过灌草平茬饲料加工、土壤改良、经济作物种植等产业化中试,以及矿区回填区生态恢复、小流域生态治理-生态衍生产业协同发展示范性实践,表明脆弱生态区治理中发展生态衍生产业具有广阔的前景。

黄河流域水资源超载地区和短缺地区的判定与动态管理

黄河流域水资源短缺,而能源富集,工业用水需求强劲,水资源开发利用率高达80%,如何协调生态保护和高质量发展的关系,实现对水资源超载地区、短缺地区的动态管理,至关重要。在分析水资源承载能力的概念定义和内涵发展的基础上,总结了水资源超载地区和短缺地区的定义和判定标准,对黄河流域九省(自治区)进行了综合研判,并从水资源刚性约束、水资源监测和管控策略等方面提出了水资源动态管理的关键措施,以期为黄河流域生态保护和高质量发展国家战略的水安全保障提供决策参考。

海河“23·7”流域性特大洪水蓄滞洪区泥沙淤积分析

为探究海河“23·7”流域性特大洪水过程中蓄滞洪区泥沙淤积特征,评估受灾情况,基于实地淤积调查和高分遥感影像,计算淤积厚度空间分布,并结合DEM数据估算蓄滞洪量和蓄滞洪区利用率。结果表明:淤积厚度插值的均方根误差E_(RMS)为1.32,纳什系数E_(NS)为0.78,蓄滞洪量计算的E_(RMS)为0.75,E_(NS)为0.92,证明研究计算方法可行,计算结果可靠;8个蓄滞洪区共蓄洪24.63亿m^(3),蓄滞洪区利用率约为36.90%,平均淤积厚度为2.60 cm,总淤积量达7.67×10^(7) t;海河流域洪水含沙量约31.14 kg/m^(3),其中大清河系和永定河系的洪水含沙量达到过去20 a平均含沙量的20~40倍;此外,研究发现海河流域西部和北部山地的淤积情况更严重,较早启用的、位于上游的蓄滞洪区淤积量更大。

海温异常对长江流域夏季典型旱涝的影响研究

为研究长江流域夏季旱涝特征及其与海温异常之间的关联性,基于中国326个气象站降水量、NCEP/NCAR再分析资料等,采用合成分析、EOF分解等方法,分析了长江流域夏季典型旱涝年的降水分布、同期大气环流及前期海温特征,并以2018年为例,初步揭示了2018年前期海温异常对大气环流的可能影响。结果表明:①长江流域夏季典型旱年,仅嘉陵江和岷沱江会表现出局部偏涝,全国为典型的Ⅰ类雨型,多雨区位于黄河流域及以北地区。前期冬季赤道太平洋表现出类拉尼娜的东冷西暖分布,同时黑潮区海温偏低,西风漂流区海温偏暖。受多海域协同作用,同期欧亚环流场上自西北向东南呈现出“+-+”三极型分布,东亚地区为自北向南“-+-”的EAP负位相。长江流域典型涝年,全国多为典型的Ⅱ类和Ⅲ类雨型,环流及海温呈现出相反特征。②2018年为典型的长江中下游偏旱年,仅在岷沱江降水偏多近3成,为历史第4多,与长江流域夏季降水的主模态正位相类似,解释方差达24%。③2018年前冬出现弱拉尼娜、春末夏初西风漂流区异常偏暖、NAT异常正位相,三者共同作用,使得东亚副热带西风急流偏北,东亚沿岸出现EAP负位相,大陆热低压明显偏强,东亚夏季风为1961年以来最强,同时副高脊线最北,造成夏季降水主雨带北推至华北、西北地区,岷沱江、嘉陵江异常多,而长江中下游异常少,为典型的Ⅰ类雨型。研究成果可为长江流域旱涝预测、水资源调度提供参考。

2013-2022年黑河流域中下游绿洲荒漠区域碳水通量及气象要素观测数据集

绿洲-荒漠系统碳水循环的观测和研究对绿洲稳定和可持续发展有重要的意义。本研究以黑河流域中游人工绿洲荒漠和下游天然绿洲荒漠区域为研究对象,基于在该区域建立的12个观测站点,系统整理了2013-2022年11套涡动相关仪、12套自动气象站和2组闪烁仪观测获取的碳水通量和气象要素数据。观测项目包括生态系统净碳交换量、蒸散发(潜热通量)、感热通量、空气温度、空气相对湿度、风速、风向、向下/上短波辐射、向下/上长波辐射、净辐射、大气压、降水、红外辐射温度、光合有效辐射、土壤温度与土壤水分廓线、土壤热通量、平均土壤温度等。本数据集经过了严格的数据处理与质量控制,可用于干旱区绿洲荒漠区域生态水文过程、碳水通量变化特征及耦合机制等研究,并为相关模式或遥感产品的真实性检验提供可靠的验证数据。

基于遥感和通量观测的实际蒸散发时空变化特征——以黄河流域水源涵养区为例

蒸散发是地表水热平衡的关键要素,分析蒸散发的时空分布特征及其影响因素,对于深入理解区域水文循环与生态系统过程至关重要。基于通量观测站数据,评估GLEAM、MTE、GLDAS和AVHRR共4种蒸散发产品在黄河流域水源涵养区的适用性,利用水量平衡方法验证其在流域尺度上的精度,并探讨实际蒸散发的影响因素。结果表明:在站点尺度上,GLEAM蒸散发产品精度最高;在流域尺度上,校正后的GLEAM蒸散发产品与实际蒸散发的相对误差在渭河南山支流区最小,其次是兰州以上地区;1982—2015年黄河流域水源涵养区实际蒸散发整体呈增加趋势,空间分布上自西到东逐渐增加;不同植被类型年均蒸散发差异较大,阔叶林的蒸散发最大(575.2 mm),其次是农田(504.3 mm),高山草甸的蒸散发最小(358.2 mm);实际蒸散发变化主要受到太阳辐射与气温的影响。

长江流域建立水资源刚性约束制度的关键问题与对策研究

南方丰水地区建立水资源刚性约束制度,是为了更好地促进生态环境高水平保护和经济社会高质量发展。基于长江流域水资源开发利用、管理现状及特点,分析了长江流域建立水资源刚性约束制度需重点研究的关键问题,并从水资源和水环境承载能力、用水定额标准、计量监测、水资源规划论证、监管考核和市场机制等方面,提出长江流域建立水资源刚性约束制度的对策建议。