Impact of Vegetation on Main Hydrological Processes：A Field Study and Its Implication for Water Quality

The impact of vegetation cover on groundwater table was assessed with the observed water level fluctuations at two monitored wells in stalled on a bare ground and a vegetated land,respectively．Substantial differences in water table behavior were observed under two land cover scenarios．Ingeneral,the water level in the east grass (EG） well was lower and had much less response to rainfall events than the WNG well mainly due to the difference in the land cover．The effect of vegetation was to lower the water level in the EG well through ET and thus reduce groundwater recharge,which in turn reduced the chemical loads to the creek．The daily and accumulative ET values were estimated with both the Penman-Monteith method and a water table recession model．It is suggested that while the Penman-Monteith method closely modeled hourly ET cycles during the day,it underestimated actual ET during an intensive mid-summer growing period,and especially underestimated actual ET when the water table was close to the landsurface．With the water table recession model,the amount of ET was estimated at its maximum ET of 7．6 mm when the water table was near the groundsurface and then decreases exponentially to zero around day 33 during a dry period with the accumulative ET of 93．9 mm,or 2．84 mm／day．The results from this study clearly demonstrate that landuse and vegetation coverage have significant effects on ET,groundwater recharge and implications for a basin-scale water cycle and chemical loads to rivers and streams．     

Anticipatory Adaptation Approaches to Climate Change--A Review and Discussion of Southern Australia’s Sustainable Water Management and Its Strategies and Shortcomings

Climate change issues has been discussed and argued for decades. It has been widely recognized that climate change will bring more serious issues to environment vulnerable areas than other areas. Southern Australia is one of the typical examples of vulnerable areas where water deficiency is enhanced by climate change. Although, this area has been successfully adapted with drought environment for decades, those shortcomings of strategies are highlighted by climate change events. In the interests of sustainable water management, Southern Australia’s experiences on possible anticipatory adaptation approaches, especially on mitigation of risks and costs of drought could be expected to provide recommendations to planning and management actions in the future     

The Effects of Water Content and Dry–Wet Cycles of Weak‐Interlayer Soil on Stability of Clastic Rock Slope

Geotechnical and Geological Engineering - The goal of this paper was to study the effect of water content change of weak interlayer soil on the stability of clastic rock slope. Direct shear tests...     

Crystal Chemistry Research of Minerals of Nigerite Group and Its Significance

SinceJacobsonandWebb (194 7)firstlyfoundthenigeriteinNigeria ,mineralogistshavefounditinmanycountriessuchasRussia (EastSiberia ,195 8) ,China(Hunan ,196 3) ,Portugal (196 5 ) ,Australia (1976 )andsoon .Greyetal.(1979)determinedaccuratelythecrystalstructureofnigerite (2 4R) .In 1988,Chenfoundakindofendmembermineralofnigerite ,whichisMg riched .ByapprovingofCommissiononNewMineralsandMineralNames (CNMMN) ,thismineralwasnamedpengzhizhongite .Inthepast ,somemineralogistsdidnotfurtherdis t…     

Research on Relationship Between Fluorine in Tap Water and That in Urine of Chinese Residents

In this study, the relationship between fluorine in drinking water and that in urine of urban residents in China is assessed. Fluorine concentrations in tap water and those in urine show a good correlation with a linear regression coefficient of 0. 9798, indicating that the fluorine concentrations in big cities under investigation are extremely low, and the main source of fluorine is tap water. The weather effect on the intake amount of fluorine is also discussed. When air temperature is above 15℃, people would intake more fluorine through drinking water with the rise of air temperature. When temperature is below 15℃, no remarkable relationship is observed between air temperature and the intake amount of fluorine. This phenomenon indicates that the main source of fluorine in China is tap water instead of foodstuff.     

Characteristics of Karst Ecosystems of Vietnam and Their Vulnerability to Human Impact

Karst in Vietnam covers an area of about 60,000 km2, i.e. 18 % of the surface of the country. The country has an annual average temperature of 24@, an annual average rainfall of 2300 mm and a relative humidity of about 90%. Karst in Vietnam is typified by peak cluster-depression landscapes ranging in elevation from 200 to over 2000 m. Tower and coastal karst landscapes also exit. Because of naturally favourable conditions, karst ecosystems are diverse and very rich. Higher plants (cormophytes) are abundant. They are represented by approximately 2000 species, 908 genera, 224 families, 86 orders and 7 phyla. They form a thick vegetation cover of evergreen tropical rainforest. Knowledge about lower plants is limited. The fauna is rich and diverse. Phyla such as Protozoa, Vermes, Mollusca and Arthropoda are yet ill known. Preliminary results show that the phylum Chordata is represented by 541 species from 80 families, 40 orders and 5 classes. There exist many precious and rare mammals, in particular some en     

Recognition of Milankovitch Cycles in the Natural Gamma—Ray Logging of Upper Cretaceous Terrestrial Strata in the Songliao Basin

Spectrogram analysis of seven natural gamma-ray logging of Member 1 of the Qingshankou Formation (K2qn1) and Member 1 and 2 of the Nenjiang Formation (K2n1-2) of Late Cretaceous age in the Songliao Basin reveals sedimentary cyclicities controlled by Milankovitch climate periodicities. The recognition of Milankovitch cycles allows estimation of an average accumulation rate of ~7.55–8.62 cm/ka for the K2qn1 sections, and ~6.69–10.16 cm/ka for the K2n1-2 sections. Two marine transgression events occurred during the deposition of K2qn1 and K2n1-2 and their ages are at ~0.74–1.10 Ma and ~2.38–4.84 Ma, respectively. Identification of Milankovitch cycles from fine-grained deep lake sedimentary rocks in the Songliao Basin may provide great potential for high-resolution stratigraphic subdivisions and correlations.     

Risk Assessment of Coal Floor Water Inrush from Underlying Aquifers Based on GRA–AHP and Its Application

Ground water inrush from underlying coal seam aquifers is a serious geohazard during coal mining in China. In order to effectively predict coal floor water inrush, the evaluation index system and evaluation standard for coal floor water inrush, containing quantitative indexes and qualitative indexes, is established on the base of conditions of aquifer and aquiclude, geologic structure and mining disturbance. Simultaneously, grey relational analysis and analytic hierarchy process are used to establish an evaluation model which efficiently overcomes the uncertainty between indexes of water inrush effects and really reflects the degree of importance for each index of water inrush effects. The model is applied to the typical working face of Yuzhou coalfield in the north of China to demonstrate the evaluation process. Compared to the water inrush coefficient method which is widely used for evaluating coal floor water inrush, the presented evaluation model in this paper accords more with the susceptibility of coal floor water inrush by multi-factor and is of nonlinear dynamic characteristics of highly complicated formation mechanism. This method offers a new tool in the assessment of ground water inrush in mine.     

The Methods of Research on Formation and Evolution of the Solar Nebula

Based on the studies of meteorites,theauthors introduce the formation and evolutionof the solar system,including condensation,heating and alteration in the solar nebula,thermal metamorphism,igneous fractionationand shock metamorphism in parent bodies ofmeteorites.Heterogeneities in chemical and     

Aproposed Area for Study of Accessory Section and Point of Terrestrial Permian—Triassic Boundary

After the establishment of the global stratotype section and point (GSSP) of the Permian-Triassic boundary (PTB), the definition of the accessory section and point (ASP) of the terrestrial Permian-Triassic boundary (TPTB) is now on the agenda. However, all good TPTB sections so far known have the following shortcoming:(1) the exact TPTB horizon is difficult to define paleontologically with high-resolution, and (2) accurate correlation between marine and terrestrial PTBs in hard to attain. In order to enhance the understanding of the nature of the global life crisis in both the marine and terrestrial environments across the Paleozoic-Mesozoic transition, these shortcomings need to be addressed. In western Guizhou and eastern Yunnan, Southwest China, some fossiliferous PTB sections which include marine, paralic and terrestrial are well-developed, allowing bed-to-bed correlation of the PTB sequences. Fortunately, the marine PTB sequence in this area is almost the same as found at the Meishan Section, where the GSSP of the PTB is located, which may provide a reliable auxiliary marker for high-resolution demarcation of the TPTB. These features fund in estern Guizhou and eastern Yunnan make this area a good place to study the ASP of the TPTB, so we propose to study the ASP of the TPTB in this area.     

Impact of bioturbation on reservoir quality and production – A review

Bioturbation is a typically small scale yet potentially significant geological process altering rock properties by reworking. For many years, bioturbation studies found application in exploration geology to estimate paleobathymetry, interpreting depositional environment and identifying key stratigraphic surfaces. These act as vital inputs to the geological models, for determination of source rock potential, reservoir quality and modeling of petroleum systems. Recently geologists extended the application of bioturbation studies to address production related challenges. Recognizing the bioturbation effects and incorporating them in reservoir simulation models can improve production predictions and enhanced oil recovery operations. This paper discusses bioturbation and its effects on reservoir quality, its performance and production.     

Geochemical Mapping——Evolution of Its Aims, Ideas and Technology

The development of geochemical mapping progressed from local geochemical prospecting through regional geochemical exploration and regional geochemical mapping to national and global geochemical mapping. This paper discusses the evolution of aims, ideas and methodology of geochemical mapping in Western countries, Russia and China. The sophistication of geochemical mapping methodology will make great contributions to solving resources and environmental problems in the 21st century.     

Research on Slope Movement and Landslide by Methods of Analytical Geomechanics

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Geochemical Mapping——Evolution of Its Aims,Ideas and Technology

The development of geochemical mapping progressed from local geochemical prospecting through regional geochemical exploration and regional geochemical mapping to national and global geochemical mapping.This paper discusses the evolution of aims,ideas and methodology of geochemical mapping in Western countries,Russia and China.The sophistication of geochemical mapping methodology will make great contributions to solving resources and environmental problems in the 21~(st) century.     

Reviews in Garnet—Biotite Geothermometer：Its Versions,Inherent Problems of Accuracy and Precision,and Perspective for Further Research

This paper briefly introduces twenty-one versions of garnet-biotite Fe-Mg exchange geothermometry,points out the sources of systematic errors inherent in geothermometry.The sources lie in that:(1) ideal Fe-Mg mixing in garnet and biotite is assumed;(2)non-ideal properties of bot garnet and biotite are not considered completely;(3) minor elements-Mn, Ca in garnet,and Al^Ⅵ,Ti,Mn in biotite are almost neglected;(4)effects of pressure on equilibrium,although little,are almost not taken into consideration,and experiments were conducted at one fixed pressure;(5)the data used for egression analysis is too scarce in quantity;(6)internal consistency of the data used for empirical calibration is not fully guaranteed;(7) the authors take energy parameters W‘s(Margule‘s parametrs)independent of pressure and temperature,though the former are actually the functions of the latter items;and (8)the most important composition-activity relationship is not consistent with the mineral compositions used for calibration.Furthermore,it is believed that empirical calibrations cannot avoid the following problems;(1) effect of retrograde metamorphism;(2)inconsistent data set;(3)effect of pressure on temperature estimation;and (4)effect of Fe^3 calculation.Exact experimental work should be done in order to accurately calibrate the geotermometer in which the Margule‘s parameters should be treated as the functions of pressure,temperature,and mineral compositions.     

Effect of Soil–Water Characteristic Parameters on Saturation Line and Stability of Slope

Rainfall infiltration is the main factor that causes slope instability. To study the effect of hydraulic parameters on the final saturation line and stability of slopes, a numerical slope model is established with a saturated–unsaturated seepage analysis method. Analysis results show the following, (1) When parameter a increases, the effective rainfall duration decreases linearly, and the ultimate safety factor increases gradually; when parameter m increases, the effective rainfall duration increases linearly, and the ultimate safety factor decreases linearly; when parameter n increases, both the effective rainfall duration and the ultimate safety factor decrease first and then remain stable. (2) When the saturated permeability coefficient decreases, the effective rainfall duration presents a crescent trend, and the ultimate safety factor decreases first and then remains the same after rainfall intensity exceeds the saturated permeability coefficient of soil. (3) When rainfall intensity is less than the saturated permeability coefficient of soil, the location of the final saturation line rises as the saturated permeability coefficient decreases and is thus independent of parameters a, m, and n.     

Impact of changing climate and land use on the hydrogeology of southeast Australia ∗

Anthropogenic climate change is the Earth's most serious large-scale environmental concern. While the projected changes of global temperatures, rainfall and surface water have been modelled in a sophisticated manner, the impact on groundwater resources is much less well constrained. In southeast Australia, the decrease in rainfall amount and an increase in temperature that are predicted by climate models are generally assumed to reduce the amount of recharge to the groundwater systems. However, the increase in recharge that has resulted from clearing of the native vegetation will almost certainly produce a greater impact on the groundwater system, increasing quantity and potentially improving quality. Additionally, the impact on recharge of changes to rainfall frequency rather than just total amount is not well documented. Overall our understanding of the impacts of climate change on groundwater systems is insufficiently advanced to make firm predictions. Indirect impacts of climate change, particularly the projected increased demand for groundwater or surface water to supplement surface water supplies also will have a major impact that may be greater than the direct effect of climate change.     

Earthquake-related Tectonic Deformation of Soft-sediments and Its Constraints on Basin Tectonic Evolution

The authors introduced two kinds of newly found soft-sediment deformation-synsedimentary extension structure and syn-sedimentary compression structure, and discuss their origins and constraints on basin tectonic evolution. One representative of the syn-sedimentary extension structure is syn-sedimentary boudinage structure, while the typical example of the syn-sedimentary compression structure is compression sand pillows or compression wrinkles. The former shows NW-SE-trendlng contemporaneous extension events related to earthquakes in the rift basin near a famous Fe-Nb-REE deposit in northern China during the Early Paleozoic （or Mesoproterozoic as proposed by some researches）, while the latter indicates NE-SW-trending contemporaneous compression activities related to earthquakes in the Middle Triassic in the Nanpanjiang remnant basin covering south Guizhou, northwestern Guangxi and eastern Yunnan in southwestern China. The syn-sedimentary boudinage structure was found in an earthquake slump block in the lower part of the Early Paleozoic Sailinhudong Group, 20 km to the southeast of Bayan Obo, Inner Mongolia, north of China. The slump block is composed of two kinds of very thin layers-pale-gray micrite （microcrystalline limestone） of 1-2 cm thick interbedded with gray muddy micrite layers with the similar thickness. Almost every thin muddy micrite layer was cut into imbricate blocks or boudins by abundant tiny contemporaneous faults, while the interbedded micrite remain in continuity. Boudins form as a response to layer-parallel extension （and/or layer-perpendicular flattening） of stiff layers enveloped top and bottom by mechanically soft layers. In this case, the imbricate blocks cut by the tiny contemporaneous faults are the result of abrupt horizontal extension of the crust in the SE-NW direction accompanied with earthquakes. Thus, the rock block is, in fact, a kind of seismites. The syn-sedimentary boudins indicate that there was at least a strong earthquake belt on the southeast side of the basin during the early stage of the Sailinhudong Group. This may be a good constraint on the tectonic evolution of the Bayan Obo area during the Early Paleozoic time. The syn-sedimentary compression structure was found in the Middle Triassic flysch in the Nanpanjiang Basin. The typical structures are compression sand pillows and compression wrinkles. Both of them were found on the bottoms of sand units and the top surface of the underlying mud units. In other words, the structures were found only in the interfaces between the graded sand layer and the underlying mud layer of the flysch. A deformation experiment with dough was conducted, showing that the tectonic deformation must have been instantaneous one accompanied by earthquakes. The compression sand pillows or wrinkles showed uniform directions along the bottoms of the sand layer in the flysch, revealing contemporaneous horizontal compression during the time between deposition and diagenesis of the related beds. The Nanpanjiang Basin was affected, in general, with SSW-NNE compression during the Middle Triassic, according to the syn-sedimentary compression structure. The two kinds of syn-sedimentary tectonic deformation also indicate that the related basins belong to a rift basin and a remnant basin, respectively, in the model of Wilson Cycle.     

Characteristics of Oil Contamination and Numerical Modelling of Its Transport in Fracture-Karst Water in Zibo City,China

In this paper, the hydraulic characteristics of the fracture-karst aquifer and the distribution patterns of petrochemical contaminants are studied. Then, a numerical model using the mixed Eulerian-Lagrangian approach is constructed to predict the distribution and transport of petrochemical compounds in groundwater. The results of numerical modelling and sensitivity analysis show that it may be a workable way for aquifer remediation to combine contamination sources control and capture zone establishment.