The present paper has made a comparison of major similarities and differences of extreme cold events between the cold and warm periods for recent 50 years, in order to gain a better insight into the impact of the global warming on extreme cold events in China. Two typical events of low temperature, ice freezing and snow disasters that occurred in January 2008 and in the winter of 1954/1955, respectively, are selected as representative cases for the cold period (1950’s-1970’s) and the warm period (1980’s-present). The contrasting study has revealed that these two events both occurred under long-persistent blocking circulation over Eurasian continent, with continuous invasions of strong cold air into China mainland. They nearly brought about similar weather disasters such as extensive low temperature, record-breaking freezing rains and exceptionally heavy snowfalls. However, due to active northward transport of warm and moist air from Bay of Bengal and Indo-China Peninsula in the warm period, the January 2008 case had longer freezing rain days and heavier snowstorms in South China, thus leading to much more severe damage to electric grids and transportations. The case of the 1954/1955 winter was a stronger, extreme cold event than the case of January 2008, in terms of magnitudes of temperature drop and severity of impact on river icing. It was gradually recovered to normal condition while the case of January 2008 had a very rapid recovery to warming condition due to impact of the global warming.

This paper examines the credibility and predictability of sediment flux of the Changjiang River that has discharged into the seas on the basis of historical database. The assumption of the study stands on the lack of sufficient observation data of suspended sediment concentration (SSC) during peaking flood period, which most likely results in the application of an inappropriate method to the downstream-most Datong hydrological gauging station in the Changjiang basin. This insufficient method (only 30-50 times of SSC observation per year), that obviously did not cover the peaking SSC during peaking floods, would lead to an inaccuracy in estimating the Changjiang sediment load by 4.7×10⁸ t/a (multiyearly) into the seas. Also, sediment depletion that often takes place upstream of the Changjiang basin has, to some extent, lowered the credibility of traditional sediment rating curve that has been used for estimating sediment budget. A newly-established sediment rating curve of the present study is proposed to simulate the sediment flux/load into the seas by using those SSC only under discharge of 60000 m³/s at the Datong station-the threshold to significantly correlate to SSC. Since discharge of 60000-80000 m³/s is often linked to extreme flood events and associated sediment depletion in the basin, un-incorporating SSC of 60000-80000 m³/s into the sediment rating curve will increase the credibility for sediment load estimation. Using this approach of the present study would indicate the sediment load of 3.3×10⁸-6.6×10⁸ t/a to the seas in the past decades. Also, our analytical result shows a lower sediment flux pattern in the 1950 s, but higher pattern in the 1960 s-1980 s, reflecting the changes in land-use in the upstream of Changjiang basin, including widely devastated deforestation during the middle 20th century.

We analyzed the statistical properties of water level extremes in the Pearl River Delta using five probability distribution functions. Estimation of parameters was performed using the L-moment technique. Goodness-of-fit was done based on Kolmogorov-Smirnov’s statistic D (K-S D). The research results indicate that Wakeby distribution is the best statistical model for description of statistical behaviors of water level extremes in the study region. Statistical analysis indicates that water levels corresponding to different return periods and associated variability tend to be larger in the landward side of the Pearl River Delta and vice versa. A ridge characterized by higher water level can be identified expanding along the West River and the Modaomen channel, showing the impacts of the hydrologic process of the West River basin. Trough and higher grades of water level changes can be detected in the region drained by Xi’nanyong channel, Dongping channel, and mainstream of Pearl River. The Pearl River Delta region is characterized by low-lying topography and a highly-advanced socio-economy, and is heavily populated, being prone to flood hazards and flood inundation due to rising sea level and typhoons. Therefore, sound and effective countermeasures should be made for human mitigation to natural hazards such as floods and typhoons.

Numerous samples taken from one core at the Beijing plain were utilized to characterize the paleoclimatic configuration of the study area and its possible relation to global control since the last interglaciation. We presented here a detailed grain-size record for the full length of Late Pleistocene, along with the optical simulated luminescence (OSL) dating. Our findings revealed that Late Pleistocene of the study area started approximately at 110 ka B.P. represented by the thick sediments of 31 m in Changping depression. Four sedimentary cycles were outlined in the core during Late Pleistocene, corresponding to marine isotope stage (MIS) 5 to 2. Controlled by regional geology and global climatic setting, eight paleoclimatic periods were identified simultaneously in the study area on the time scale of 10⁴ year, with the warm and moist climate being found at 110-96, 92-76, 67-56, and 28-18 ka B.P.. The climatic instabilities on a millennial scale in Late Pleistocene were characterized largely by the occurrence of 6 strong Heinrich events shown by comparatively coarse groups. These variations correlate well with those documented in the GRIP Greenland and in the Northern Atlantic Ocean, though more complex features may exist on the long time scale.

This paper presents an image analysis method for automated quantification of charcoal total area, focusing on the charcoal fractions less than 160 ?m observed on 14 pollen slides from Grotta Reali samples. Four fire signals were recorded with 4 high values in the microcharcoal concentration curve. On the basis of modern microcharcoal study, mean length/width ratio of the microcharcoal particles was applied in an archeological context as an indicator of vegetal type (wood, grass or leaves). Therefore, the 4 fire signals were separated into two types: high concentration with high length/width ratio, and high concentration with low length/width ratio. Two fire signals might be interpreted as anthropic fire based on hearth or combustion areas, as inferred from archeological remains.

Poland, like other EU countries, is obliged to implement the Water Framework Directive (2000/60/WE) by the end of 2015. The main objective of the Directive is to provide normative quality of all water resources (surface, underground and coastal sea waters). To reach this goal, reduction of water pollutant emission to the environment is needed. Our project focuses on pollution from agricultural sources which share in global pollution, which is high and growing. This is due to both intensification of agricultural activities and ignoring Agricultural Good Practice Code rules by farmers. In view of the above, this project is expected to provide analysis of selected catchments; especially those exposed to agricultural pollution risk, and propose adjustment strategies for new trends, still keeping in mind environment protection.

Our project concerns the area further called “sensitive area” (according to the rules of Regional Water Management Board in Warsaw). A part of Zglowiaczka river catchments in central Poland was defined as sensitive area (125.3 km²) where reduction of nitrogen and phosphorus run-off from agricultural land to water resources is especially needed. This is a typical agricultural district characterized by good soil quality (predominance of black swampy soil with deep and fertile humus layers). Due to this, it is the first and foremost high quality agricultural land, and almost forestless. The main topic of the research, with the use of the SWAT model, is to propose different means for reduction of migration of P and N to surface waters. Another problem is retention of water for actual and future irrigations. After model verification, calibration and validation, several climatic changes and reclamation strategies will be tested and simulated by the model to find the most effective and profitable solutions.

The project focuses on supporting administration and self-governmental organization in the implementation of effective strategies of catchments management based on a modeling approach. This method enables analysis of trends and early warning system against excessive pollution load. Enhancement of the ecological education level and activation of local population for implementation of EU directives are also very important factors.

In many metropolitan regions, natural sources contribute a substantial fraction of volatile organic compound (VOC) emissions. These biogenic VOC emissions are precursors to tropospheric Ozone (O₃)formation. Because forests make up 59% of the land area in Taiwan, the biogenic VOC emissions from forests and farmland could play an important role in photochemical reactions. On the other hand, anthropogenic emissions might also be one of the major inputs for ground level O₃ concentrations. Hence, emission inventory data, grouped as point, area, mobile and biogenic VOC sources, are a composite of reported and estimated pollutant emission information and are used by many air quality models to simulate ground level O₃ concentrations. Before using relevant air quality models, the emission inventory data generally require huge amounts of processing for spatial, temporal, and species congruence with respect to the associated air quality modeling work. The fist part of this research applied satellite remote sensing and geographic information system (GIS) analyses to characterize land use/land cover (LULC) patterns, integrating various sources of anthropogenic emissions and biogenic emissions associated with a variety of plant species. To investigate the significance of biogenic VOC emissions on ozone formation, meteorological and air quality modeling were then employed to generate hourly ozone estimates for a case study of a high ozone episode in southern Taiwan, which is the leading industrial hub on the island. To enhance the modeling accuracy, a unique software module, SMOKE, was set up for emission processing to prepare emission inputs for the U.S. EPA’s Models-3/CMAQ. An emission inventory of Taiwan, TEDS 4.2, was used as the anthropogenic emission inventory. Biogenic emission modeling was accomplished by BEIS-2 in SMOKE, with improvement of local LULC data and revised emission factors. Research findings show that the majority of biogenic VOC emissions occur in the mountainous areas and farmlands. However, the modeling outputs show that downwind of the most heavily populated and industrialized areas, these biogenic VOC emissions have less impact on air quality than do anthropogenic emissions.

This study presents a basin-scale integrative hydrological, ecological, and economic (HEE) modeling system, aimed at evaluating the impact of resources management, especially agricultural water resources management, on the sustainability of regional water resources. The hydrological model in the modeling system was adapted from SWAT, the Soil and Water Assessment Tool, to simulate the water balance in terms of soil moisture, evapotranspiration, and streamflow. An ecological model was integrated into the hydrological model to compute the ecosystem production of biomass production and yield for different land use types. The economic model estimated the monetary values of crop production and water productivity over irrigated areas. The modeling system was primarily integrated and run on a Windows platform and was able to produce simulation results at daily time steps with a spatial resolution of hydrological response unit (HRU). The modeling system was then calibrated over the period from 1983 to 1991 for the upper and middle parts of the Yellow River basin, China. Calibration results showed that the efficiencies of the modeling system in simulating monthly streamflow over 5 hydrological stations were from 0.54 to 0.68 with an average of 0.64, indicating an acceptable calibration. Preliminary simulation results from 1986 to 1995 revealed that water use in the study region has largely reduced the streamflow in many parts of the area except for that in the riverhead. Spatial distribution of biomass production, and crop yield showed a strong impact of irrigation on agricultural production. Water productivity over irrigated cropland ranged from 1 to 1640 USD/(ha·mm^-1), indicating a wide variation of the production conditions within the study region and a great potential in promoting water use efficiency in low water productivity areas. Generally, simulation results from this study indicated that the modeling system was capable of tracking the temporal and spatial variability of pertinent water balance variables, ecosystem dynamics, and regional economy, and provided a useful simulation tool in evaluating long-term water resources management strategies in a basin scale.

Heap leaching is essentially a process in which metals are extracted from mine ores with lixiant. For a better understanding and modeling of this process, solute transport parameters are required to characterize the solute transport system of the leach heap. For porous media like leach ores, which contain substantial gravelly particles and have a broad range of particle size distributions, traditional small-scale laboratory experimental apparatus is not appropriate. In this paper, a 2.44 m long, 0.3 m inner diameter column was used for tracer test with boron as the tracer. Tracer tests were conducted for 2 bulk densities (1.92 and 1.62 g/cm³) and 2 irrigation rates (2 and 5 L/ (m²·h^-1)). Inverse modeling with two-region transport model using computer code CXTFIT was conducted based on the measured breakthrough curves to estimate the transport parameters. Fitting was focused on three parameters: dispersion coefficient D, partition coefficient β, and mass transfer coefficient ω. The results turned out to fall within reasonable ranges. Sensitivity analysis was conducted for the three parameters and showed that the order of sensitivity is β>ω>D. In addition, scaling of these parameters was discussed and applied to a real scale heap leach to predict the tracer breakthrough.

According to the ecosystem assessment framework developed by the Millennium Ecosystem Assessment (MA), this paper designs an evaluation system of ecosystem services in Poyang Lake area. On the basis of relevant variables disaggregated to 1 km grid using the gridded 1 km, this paper employs factor analysis to extract a number of factors which characterize the ecosystem services of Poyang Lake area. The extracted principal component are then represented onto 1 km×1 km grids by spatial clustering analysis to recognize and identify the minimal but consistent mapping units for ecosystem services which can be used to delimit the boundaries of ecological service zones. The research identifies ten ecosystem service zones in Poyang Lake area according to the consistent principle of core ecosystem service unit. Four kinds of core ecosystem services including supporting function, provisioning function, regulating function and cultural function are identified and represented. The research results could provide both spatially and temporally valuable decision-making information for sustainable ecosystem management in the targeted area.

Fe²⁺ oxidation by Acidithiobacillus ferrooxidans in pure and mixed cultures was investigated in batch cultures in the presence of arsenate. The pH value was periodically monitored and Fe²⁺ content was analyzed by the 1,10-phenanthroline method. ICP-AES was employed for the analysis of As(V) concentration in the solution phase. Precipitates were collected and analyzed by X-ray diffraction. Slight enhancement of iron bio-oxidation was observed in mixed cultures with the two greatest As(V) concentrations (1.0 and 5.0 mg/L As), which were enriched from sediment samples in an abandoned copper mine site. As(V) concentrations decreased with time, indicating either the co-precipitation with or the adsorption by jarosite, the major sink of solid phase. Our data suggest that biogenically synthesized jarosite may play an important role in the attenuation of soluble arsenate in natural aquatic environments.

Different sedimentary settings can influence preservation of pollens, which would lead to mis-interpretation of fossil pollen spectrum. This study investigates the influence on the preservation of Pinustabulaeformis pollen by simulating alkaline and oxidative environment in the laboratory. There was no obvious change in the content of Pinustabulaeformis pollen while comparing the original with the ones that were immersed with 10% NaOH liquor for ten days, or boiled for five hours, and or boiled with 20%-30% NaOH for one hour, respectively. However, the pollen fossils were obviously corroded and eroded after being boiled with 40% NaOH for one hour and were seriously corroded after five hours. The result indicates that Pinus tabulaeformis pollen is quite durable in alkaline environment and heating condition within a shorter period of time, although alkaline environment has a disadvantage for itspreservation. We also tested the influence of oxidation on Pinus tabulaeformis pollen preservation with KMnO₄ as oxidant. The result presents that the number of remaining Pinustabulaeformis pollen grains decreased quickly after being dipped in KMnO₄ along with extending the reaction time and reinforcing oxidant. The rate of remnant pollen grains was less than 1% after being dipped with 2% KMnO₄ for one hour. It is suggested that oxidative environment has stronger influence on Pinus tabulaeformis pollen preservation than alkaline environment.

The leaves of six plant species and the corresponding leaf residues collected in water from the two-year simulation experiments were analyzed in n-alkane distributions by gas chromatography (GC) and gas chromatography-mas spectrometry (GC/MS). The leaf n-alkanes keep unchanged in the dominant homologues when soaked in tap water for two years. The most significant change was observed in carbon preference index (CPI), with enhanced values being found in leaf residues collected from water. This is contradictory with the previous reports showing the lower CPI values during sinking and burial processes in natural aquatic environments. The elevated CPI values from leaf residues might be related to the low amount of microorganisms in the water used in the simulation experiment, and the enhanced solubility of even-carbon-numbered n-alkanes via van der Waals attraction. In contrast with herbaceous plants, the woody plants appear to show relatively great variations in both the CPI and the average chain length (ACL) values of n-alkanes after submerged in water for two years. Our data clearly show the differentiated decomposition between woody and herbaceous leaves, with the woody leaves suffered from much stronger decomposition. This observation suggests that in comparison with the grassland, the forest vegetation might result in relatively low authentic signals to be preserved in the n-alkane distributions in aquatic sediments.

Surface soil moisture is one of the crucial variables in hydrological processes, which influences the exchange of water and energy fluxes at the land surface/atmosphere interface. Accurate estimate of the spatial and temporal variations of soil moisture is critical for numerous environmental studies. Recent technological advances in satellite remote sensing have shown that soil moisture can be measured by a variety of remote sensing techniques, each with its own strengths and weaknesses. This paper presents a comprehensive review of the progress in remote sensing of soil moisture, with focus on technique approaches for soil moisture estimation from optical, thermal, passive microwave, and active microwave measurements. The physical principles and the status of current retrieval methods are summarized. Limitations existing in current soil moisture estimation algorithms and key issues that have to be addressed in the near future are also discussed.

RegCM3 (REGional Climate Model) simulations of precipitation in China in 1991 and 1998 are very sensitive to the cumulus parameterization. Among the four schemes available, none has superior skills over the whole of China, but each captures certain observed signals in distinct regions. The Grell scheme with the Fritsch-Chappell closure produces the smallest biases over the North; the Grell scheme with the Arakawa-Schubert closure performs the best over the southeast of 100°E; the Anthes-Kuo scheme is superior over the northeast; and the Emanuel scheme is more realistic over the southwest of 100°E and along the Yangtze River Basin. These differences indicate a strong degree of independence and complementarity between the parameterizations. As such, an ensemble is developed from the four schemes, whose relative contributions or weights are optimized locally to yield overall minimum root-mean-square errors from observed daily precipitation. The skill gain is evaluated by applying the identical distribution of the weights in a different period. It is shown that the ensemble always produces gross biases that are smaller than the individual schemes in both 1991 and 1998. The ensemble, however, cannot eliminate the large rainfall deficits over the southwest of 100°E and along the Yangtze River Basin that are systematic across all schemes. Further improvements can be made by a super-ensemble based on more cumulus schemes and/or multiple models.