在分析鄂尔多斯市生态空间网络拓扑结构和鲁棒性的基础上,提出节点最低和最大介数增加(Low and maximum betweenness addition,LMBA)增边优化策略,同时与采用RA、LDF和SMB 3种增边策略的优化结果进行了对比.结果表明:鄂尔多斯生态空间网络有262个节点、402条边,网络直径为38,节点最大介数为418,最大连通度为25.网络连通度低,重要节点少且均位于网络西部,网络极不均匀,当网络结构遭到破坏时,进行自我恢复的能力比较强,但维持自身连通性的能力非常弱.增边94条后,LMBA策略优化后网络直径为16、节点最大介数为796、最大连通度为49,网络重要节点增多,网络整体效率明显提升;RA、LDF策略也使网络连通度极大增强,SMB策略的网络连通性增强效果不显著,重要节点增多且东移,网络结构比优化前更均匀.遭到攻击后,网络的连接鲁棒性大大增强,恢复鲁棒性也有所提升.与其他策略对比,LMBA策略的连接鲁棒性在两种攻击模式下、节点恢复鲁棒性在随机攻击模式下表现最优,节点恢复鲁棒性在恶意攻击下、边恢复鲁棒性在两种攻击模式下表现较优且稳定,说明该策略网络连通性强、结构均匀,综合表现最优.在遭受攻击过程中,LMBA策略维持自身连通情况的能力较优且稳定,节点和边的恢复能力也较优.

以鄂尔多斯市为典型研究区,以2000、2005、2010、2015、2018年研究区景观格局数据和气象水文数据为研究素材,基于复杂网络理论、景观生态学和GIS空间分析技术,定量研究鄂尔多斯市景观格局的时空演变规律,并探究各级子流域的水源涵养深度,再将研究区景观格局演变数据和生态水文数据与由多个决定景观特征的因子构建的景观生态网络进行耦合分析,为研究区景观格局优化及生态环境建设提供参考.结果 表明:在研究期内鄂尔多斯市的耕地不断减少,林地、草地、水域和建设用地均有一定程度的增加;景观演变主要是耕地、林地和水域之间的转化,林地、水体的景观演变最为剧烈,耕地、草地和建设用地相对平稳;鄂尔多斯地区整体水源涵养能力偏低,相对而言,东部地区的水源涵养能力高于西部地区,随着时间的推移,水源涵养深度高值逐渐南移;构建的鄂尔多斯市景观生态网络共342个生态节点、402条生态廊道,基于度低者优先的增边策略增加了119条廊道;优化后的网络连通度和连通鲁棒性均明显提升,网络中生态流更为畅通.

以内蒙古自治区赤峰市翁牛特旗为研究区,采用2008、2013、2018年相同月份的遥感影像,结合翁牛特旗地区土地利用数据,将景观类型分为耕地、林地、草地、水域、建设用地和未利用地6类,进行景观格局指数分析,选取6个景观类型水平指数和6个景观水平特征指数,分析不同粒度对景观格局各指数的影响.研究结果表明:在景观水平格局指数中,斑块密度从0.40个/hm2下降到0.32个/hm2,香农多样性从1.37增加到1.45,香农均匀性从0.76增加到0.81,说明尚未形成优势景观,景观破碎度加剧;在景观类型水平上,随着粒度的变化斑块面积百分比没有明显变化,其他景观类型均随粒度的变化而变化.其中,在2013年和2018年水域对斑块密度的粒度效应反映较为强烈,分别从0.005个/hm2增加到0.046个/hm2、从0.010个/hm2增加到0.046个/hm2;未利用地对有效网格面积的粒度效应反映较为强烈,从24596 m2增加到40697 m2;建设用地对聚集度、凝聚度的粒度反映较为强烈,分别从0.9减少至0.3、从94％减少至49％.

论文以华北平原某垃圾场为例,选取低环萘(2环)和高环苯并[ghi]苝(6环)即迁移能力最强与最弱的两类多环芳烃的代表性物质为研究对象,采用0.01mol/LCaCl2溶液与垃圾渗滤液两种背景溶液,通过试验分析黏性土对多环芳烃吸附动力学、等温吸附性,揭示出垃圾渗滤液中多环芳烃在包气带黏性土中吸附规律和机理,这一研究对探讨黏性土吸附垃圾中多环芳烃的阻隔规律和地下水污染防治具有重要意义.

Researching the watershed-scale spatiotemporal groundwater and surface water mixing function, groundwater recharge heights and age can provide important information to watershed water sources management and water pollution controlling. In this study, 20 groundwater samples, 6 precipitation samples, and 40 surface water samples in the Yiluo River watershed in middle China were collected, and the mixing function between groundwater and surface water, recharge height, and age of groundwater was studied by using hydrochemistry (Cl, DO, EC, pH), radioactive isotopes (14C), and stable isotopes (13C, 18O, 15N). The results showed that river and shallow groundwater had frequent interaction. Evaporation function played a major role in the groundwater recharging process. Groundwater age displayed spatial and seasonal variations, and the age ranged from 660 to 2800 years (dry season) and 560 to 1800 years (wet season) in downstream and midstream, while the age range from 12,025 to 143,600 years (dry season) and 10,560 to 12,650 years (wet season) in upstream. The average recharge height of downstream and midstream both in dry and wet seasons is about 576.00 to 908.70 m. While in upstream, both, in the dry and wet seasons, ranged from 1285 to 2680 m. The mixing function between groundwater and surface water displayed spatiotemporal variety. These results of this study can provide useful information for the watershed-scale water resources management.

Slow sand filters (SSFs) have been shown to effectively improve water quality. The aim of the present study was to obtain low-cost materials (LCMs) as filter mediums (FMs) to efficiently purify harvested rainwater and to document the relationship between bacterial community structure and water purification. The red clay was mixed with crushed limestone and crushed brick, respectively. The mixtures or brick powder were used as the filter media for SSFs. Laboratory column tests were conducted in conjunction with the monitoring of representative water quality parameters (COD, NH4+, CFU and total coliforms) to estimate the performance of low-cost material slow sand filters (LCM-SSFs), including the time needed for biofilm maturation. The relationship between bacterial community structure and SSF performance was determined using a combination of 16S rRNA gene sequencing and an array of statistical techniques. The results demonstrated that LCM-SSFs perform well in purifying harvested rainwater, and are of superior economic benefit. LCMs had a stronger adsorptivity than quartz sand, which enhanced the purification of harvested rainwater before the biofilms matured, and shorten the time required for biofilm maturation. During the 90-day laboratory experiment, a mixture of crushed limestone and red clay exhibited the best performance. The abundance of Opitutae could be used as a potential indicator of NH4+ removal efficiency by SSFs. Schmutzdecke was characterized by abundant, diverse and evenly distributed bacterial communities that produced rich, stable and robust environmental functions, and that possessed an excellent purifying capacity. Environmental conditions associated with low ecological stress, such as neutral pH filter mediums and lucifugal experimental conditions, were conducive to the diversity and evenness of effluent bacterial communities and improved the performance of LCM-SSFs in purifying harvested rainwater.

晋祠泉和兰村泉是山西著名的岩溶大泉,受自然条件变化和人类活动的影响,两个泉于20世纪末相继断流.针对山西省政府提出的要使晋祠、兰村泉水复流的生态修复目标任务,文章在泉域水文地质调查基础上,就泉水复流密切相关的四个关键性岩溶水文地质条件问题开展研究并提出了新认识.核实了目前划定的晋祠—兰村泉域边界,依据最新资料对现行的晋祠、兰村泉域边界提出了7处修正,修改后晋祠泉域面积由2 030 km2变为2 713 km2,兰村泉域面积由2 500 km2变为2 614 km2.汾河二库在蓄水后库区的主体部分划归到晋祠泉域而非兰村泉域,其渗漏补给是造成近年来晋祠泉域区域岩溶地下水位大幅回升的主要原因.确定了晋祠泉域内盘道—马家山断裂带是一个岩溶水强富水带,也是岩溶地下水从北部中、上寒武统含水岩组向南部中奥陶统含水岩组的转换带.圈定了晋祠泉域:玉门河南峪村—杜儿平煤矿东侧—官地矿与白家庄矿交界处—龙山—明仙村东—晋祠泉的岩溶地下水强径流带.这些认识是开展晋祠—兰村泉域岩溶地下水资源评价、地下水开发管理和保护的基础,更是制定晋祠、兰村泉水复流方案的重要依据.

Fertilization and aglime (agricultural lime) application, as important agricultural activities in acid soil, exert an influence on the fluxes of carbon both between and within ecosystems. Animal manure added to soil can elevate the soil CO2 and release organic acid due to microbial decomposition of the high organic matter content of animal manure. Additionally, the elevated CO2 can accelerate carbonate weathering in alkaline soil, such as lime soil. However, in acidic soil, it is unclear whether the chemical weathering of additive aglime can be quickened by the elevated CO2 due to animal manure addition. Thus, to ascertain the impact of animal manure addition on aglime weathering in acidic soil and to understand the weathering agent of aglime or underlying carbonate in the acidic soil profile, we established two contrasting profiles (control profile and manurial profile) in a cabbage-corn or capsicum-corn rotation in a field experiment site located in the HuaXi district of Guiyang, China, and buried carbonate rock tablets at different depths of soil profiles to calculate the dissolution rate of carbonate rock by monitoring the weights of the tablets. The results indicated that soil CO2 increased due to animal manure addition, but the rate of dissolution of the carbonate rock tablets was reduced, which was attributed to the increase in the pH in acidic soil after animal manure addition because the relationship between the dissolution rate of carbonate rock and soil pH indicated that the weathering rate of carbonate rock was controlled by pH and not by CO2 in acidic soil. Thus, the contribution of H+ ions (mainly exchangeable acid) in acid soil as a weathering agent to the weathering of underlying carbonate (and/or aglime) may lead to the overestimation of the CO2 consumption through chemical weathering at the regional/global scale using hydro-chemical methods.

Urban ecological infrastructure is the foundation of urban sustainable development.The ecology of arid area in West China is very fragile.The ecological infrastructure network of county scale is significant to ensure the stable development in the arid area.Under the background of rapid urbanization, Dengkou County, the typical ecological fragile zone in West China, was chosen as the study area.Landscape pattern index, landscape transfer network and kernel density mapping were used to analyze the landscape pattern evolution of the county.Then the ecological resources were identified and classified, and ecological corridors and ecological nodes were identified based on the Cost Path model.In addition, the urban ecological infrastructure network in the county scale was developed.The results show that the landscape of the county in 2014 was immensely damaged, and the ecological flow of landscape was poor.The transfer between urban/construction land, desert shrub land, farmland and desert determines the characteristics of the whole landscape changes in Dengkou County.There were totally 28 kinds of transfer relations during the 14 years.The optimization network of ecological infrastructure in county scale based on the Cost Path model is consisted of 391 ecological resources, 47 466 ecological corridors and 799 ecological nodes.The ecological infrastructure optimization network constructed for Dengkou County at the arid area is an important guarantee for the development and urbanization of the county, and is of significance for the ecological planning in arid area.

为了更加快速、准确的提取出荒漠绿洲区土地利用类型,采用面向对象的分类方法,利用eCognition软件对荒漠绿洲区磴口县高分一号遥感影像进行多尺度分割,并对分割尺度、颜色、形状、紧密度和光滑度等参数设置进行多次的试验,最终确定了荒漠绿洲区高分一号遥感影像信息提取的最佳分割尺度与分类规则.对研究区高分一号影像也采用最大似然法分类法进行分类,分类精度为78.65%,kappa系数为0.6984,面向对象分类方法的分类精度为92.51%、kappa系数为0.8767,荒漠绿洲区面向对象的分类方法提取精度明显优于最大似然法.

将磴口县作为研究区,按照荒漠景观和绿洲景观两大主要景观类型对1989,1995,2000,2007,2010和2014年遥感影像进行分类,利用荒漠绿洲景观重心迁移模型、转移矩阵和景观格局指数系统研究了磴口县荒漠绿洲景观时空演变以及格局特征.结果表明:1)25年来荒漠景观逐渐向西北迁移,绿洲景观逐步扩张,积极的沙漠化治理获得成效.2)严重沙漠化景观和重度沙漠化景观大面积转出为其他景观,中度和轻度流转最为频繁,非沙漠化景观逐渐成为主体景观.3)轻度沙漠化景观和中度沙漠化景观破碎化程度较大,轻度沙漠化景观的人类干扰程度更大,斑块更为复杂.

To provide scientific foundation for the protection of groundwater environment in Sanjiao block of Lin County in Shanxi Province,the groundwater numerical simulation was conducted to predict the migration of hydro-fracturing fluid in coal bed.A hydrogeological conceptual model was set up based on the analysis of geo-logical structure.The 3#group coal bed within Shanxi Formation was conceptualized as a confined aquifer,over-laid by Permian sandstone and mudstone and underlaid by interbeds of mudstone and sandstone functioning as quitards.In addition,groundwater boundary conditions were confirmed.Migration of hydro-fracturing fluid in coal bed of the study area was modeled and predicted.Results indicate that the migration range of hydro-fractu-ring fluid in the coal bed is within coal hydro-fracturing impact limits,about 300 meters around fractured well.

Urbanization is a common trend for all the countries in their development,and is a mark of human civilization and progress.The trend of urbanization in China is consistent with the total trend of the world.So it is of great significance to find out the work progress of urban geological work in foreign countries.In this paper, the definition,connotation,task and work content are summarized and expounded.Then the main urban geolo-gical work of foreign countries is reviewed and summarized,in order to provide reference of the related work. On this basis,the development trend of urban geology is analyzed from nine aspects,including theory research, information system,working depth,working focus,mechanism construction,and so on.Finally,combining with the present situation of geological work in our country,the focus,content,research level of urban geology in China are discussed in order to offer reference to urban geological work in China.

PTA wastewater discharged from a factory was selected as the research object in this project and CODcr was selected as the characteristic pollution factor. Static adsorption and soil column leaching experiments of silty clay and clayey soil were carried out to study the adsorption, bio-degradation and dispersion coefficient of CODcr in PTA wastewater. Hydrus-1D was used to build the convection-diffusion model to demonstrate the migration of PTA wastewater in the vadose zone. The results indicate that silty clay and clayey soil in the vadose zone can adsorb, degrade and impede the contaminants in PTA wastewater; however, the coefficient of adsorption and degradation were very low, they were down to 0.0002 L g(-1), 0.0003 L g(-1) and 0.0097 d(-1), 0.0077 d(-1) for silty clay and clayey soil, respectively. Under the virtual condition that, wastewater in the sewage pool is 5 m deep, CODcr concentration is 4000 mg L-1, vadose zone is 21 m, PTA wastewater will reach the phreatic surface after 20.87 years. When wastewater in the sewage pool is 7 m with other conditions unchanged, after 17.18 years PTA wastewater will reach groundwater. The results show that there is a higher pollution risk for groundwater if we do not take any anti-seepage measures.

The chemical weathering can consume atmosphere/soil CO2. Human activities such as pollution, fertilization and acid precipitation have exerted a large impact on CO2 intake by carbonate weathering. Thus, based on the analysis on chemical component change of the karst groundwater in the karst ridge watershed of Conglin Village, Fuling District of Chongqing City, the influence of human activities such as fertilization, sewage discharges from mustard tuber processing, breeding industry and acid rain precipitation on carbonate weathering and CO2 intake in 1980, 2003 and 2006 was studied. The results showed that CO2 intake by carbonate rock declined with year. Because H+ derived from acid sewage discharge, fertilization and acid precipitation reacted with carbonate rock when mustard tuber production and swine breeding were developed fleetly after 2000 as well as the burning amount of high-sulfur coal augmented persistently, which led to the increase of (Ca2++Mg2+)/HCO3-. The difference on charge between Ca2++Mg2+ and HCO3- was balanced by NO3-+SO42-. The control on pollution and acid rain, especially the pre-neutralization of acid waste water, would rejuvenate the atmospheric CO2 intake strength of carbonate weathering besides the protection of water and soil environment.

Thanks to the increasingly-improved flood-control engineering projects in the lower reaches of the Yellow River safety has been maintained over the past 50 years. Nonetheless, the rising trend of the riverway bed of the lower reaches has not been reversed. This has been a potential hazard to the local people. Using various investigation methods we basically ascertain the geological environment of the lower reaches including active faults, crust uplift, ground subsidence, seismic activities, engineering conditions of dike foundation, hydraulic conditions and fluvial geomorphology, etc. Based on the comprehensive analysis of the instability modes and corresponding influencing factors we choose fuzzy comprehensive assessing method to assess the ground stability, dike-foundation stability and riverway stability and general stability of the suspended river. The results show that the stability of the suspended river of the Yellow River could be classified into four grades, i.e. “basically stable, unstable, very unstable and extremely unstable” and 11 segments. Taking into account future tectonic faults, earthquake, difference between riverway and ground outside riverway, riverway shapes, historical breaches, ground fluidization and seepage deformation, etc., we further find out 17 the most unstable sites, among of which 7 are the most possible breaching sites, i.e. Wuzhi, Zhongmou, Kaifeng, Fengqiu, Dongming, Changyuan and Dong’e. Calculations of the possible inundation scope and area, number of affected people, economic losses and environment damage etc. Any of them, if breached, could bring about disaster results in the lower reaches of the Yellow River.

To ascertain the impact of animal manure addition on aglime weathering in acid soil and to understand the contribution of carbonate weathering to the atmospheric/soil CO2 in acid soil profile, two contrastive profiles (control profile and manurial profile) in the HuaXi district of Guiyang, China were established, and carbonate rock tablets were buried in different depths of soil profiles to determine the weathering rate of aglime. The results showed that soil CO2 increased owing to animal manure addition, but the dissolution of carbonate rock tablets decelerated, which was attributed to the increase of pH in acidic soil after animal manure addition. The relationship between the dissolution rate of carbonate rock tablets and soil pH indicated that the weathering rate of aglime was controlled by pH rather than CO2 in acid soil. Thus, the contribution of protons in acidic soil as a weathering agent to riverine alkalinity may lead to the overestimation of CO2 consumption via chemical weathering at regional/global scale using hydrochemical methods.

A much improved understanding of how farmyard manure application may affect carbonate rock dissolution is needed in order to predict possible feedbacks between the rock carbon cycle and the global climate system. Two carbonate mineral rock tablets; dolomite and limestone were buried at six depths between 0 and 110 cm in a soil typical of the subtropical karst area in Guiyang City, Guizhou Province. The extent of tablet dissolution, soil CO2, soil pH, soil water content, soil mineral and chemical composition, and chemical composition of soil water were tested in order to assess the degree of dissolution under manure application over the course of one year. The results show that manure addition decreases the dissolution rate of carbonate rocks; limestone and dolomite by between 11.7%-116.9% and 25.0%-65.69% respectively, with the dissolution rate of limestone consistently exceeding that of dolomite under the same conditions. Our data indicates that the rate of pedogenesis of the dolomite and limestone rocks is decreased as much as 35.77% and 59.41% respectively, as a result of manure application. Moreover, the results suggest that manure application accelerated the generation of soil CO2, with soil CO2 concentration increasing on average by 93.94%, and the CO2 flux increasing by 67.64% compared with the control profile. Finally, the data also indicates that manure decreases CO2 uptake by dissolution of carbonate rocks by 25.50%-39.45% on a Guiyang city scale. The counteraction of the CO2 sink contributed by karst water due to farmyard manure utilization in general karst area (both dolomite and limestone) however was 59.41%-62.72%, indicating the application of manure successfully reduces both dissolution and CO2 release to the atmosphere.

Waste production in cities is increasing with growing urbanization in China. As the incorrect disposal of waste can lead to environmental problems and pollution of groundwater, it is important to asses the suitability of sites for waste disposal. In this paper, 831 waste disposal sites in 295 cities in China were investigated, and suitability assessments of 508 sites were made. The results showed that the number of "suitable", "moderately suitable", "barely suitable" and "unsuitable" waste disposal sites accounted for 17.7%, 29.5%, 14.2% and 38.6% of the sites investigated, respectively. The pollution condition of 465 sites was examined, and the results indicated that groundwater in 282 sites was contaminated. Groundwater samples from two polluted sites were collected and analyzed to inform a proposal on urban waste disposal.

The pattern of adsorption,degradation and migration of CODCr of the wastewater was examined through the static batch experiments and the soil column methods,and the parameters required with the numerical simulation were obtained.As a result,the partition coefficients,longitudinal dispersivity and the first-order degradation coefficient of CODCr on silt were 0.155cm3/g,0.15cm,and 0.009 7/d,respectively.The migration of CODCr in the soil columns was simulated with the Hydrus-1D software.The results show that a good correlation exists between the measured values and the simulated ones.The migration depths within different times were predicted by the correspondence mathematical models.