长江三角洲城市体系中不同等级城市用地空间结构演变——以上海、杭州、无锡、慈溪为例

以多时相Landsat MSS、TM和ETM影像为数据源,利用遥感和GIS手段,提取不同等级城市（上海市、杭州市、无锡市和慈溪市）1979年、1990年、1995年、2000年和2005年5个时相的城市用地信息,分析了城市体系中不同等级城市用地空间结构演变特征.结果表明,不同等级城市的空间结构演变过程和扩展特征各不相同.     

Modelling the impact of wind stress and river discharge on Danshuei River plume

A three-dimensional, time-dependent, baroclinic, hydrodynamic and salinity model, UnTRIM, was performed and applied to the Danshuei River estuarine system and adjacent coastal sea in northern Taiwan. The model forcing functions consist of tidal elevations along the open boundaries and freshwater inflows from the main stream and major tributaries in the Danshuei River estuarine system. The bottom friction coefficient was adjusted to achieve model calibration and verification in model simulations of barotropic and baroclinic flows. The turbulent diffusivities were ascertained through comparison of simulated salinity time series with observations. The model simulation results are in qualitative agreement with the available field data.     

Basin-wide cooperative water resources allocation

The Cooperative Water Allocation Model (CWAM) is designed within a general mathematical programming framework for modeling equitable and efficient water allocation among competing users at the basin level and applied to a large-scale water allocation problem in the South Saskatchewan River Basin located in southern Alberta, Canada. This comprehensive model consists of two main steps: initial water rights allocation and subsequent water and net benefits reallocation. Two mathematical programming approaches, called the priority-based maximal multiperiod network flow (PMMNF) method and the lexicographic minimax water shortage ratios (LMWSR) technique, are developed for use in the first step. Cooperative game theoretic approaches are utilized to investigate how the net benefits can be fairly reallocated to achieve optimal economic reallocation of water resources in the second step. The application of this methodology to the South Saskatchewan River Basin shows that CWAM can be utilized as a tool for promoting the understanding and cooperation of water users to achieve maximum welfare in a river basin and minimize the potential damage caused by water shortages, through water rights allocation, and water and net benefit transfers among water users under a regulated water market or administrative allocation mechanism.     

中国黄河三角洲的草地

黄河三角洲是中国最大的三角洲之一。草地是本地区主要自然植被类型。芦苇群落、白茅群落、獐茅群落和盐地碱蓬群落是该草地的4个基本类型。本文研究了它们的性质及其环境因子特征。草地的平均年产草量可达2000kg/hecta。将放牧区与割草区分开、控制放牧的时间和强度、限制牧群的数量以及适宜地造林是合理利用草地资源的重要途径。建立自然保护区对于科学研究、草地生态系统的保护是必要的。     

FLOOD ROUTING MODELS IN CONFLUENT AND DIVIDING CHANNELS

By introducing a water depth connecting formula, the hydraulic equations in the dividing channel system were coupled and the relation of discharge distribution between the branches of the dividing channels can be yielded. In this manner, a numerical model for the confluent channels was established to study the variation of backwater effects with the parameters in the channel junction. The meeting of flood peaks in the mainstream and tributary can be analyzed with this model. The flood peak meeting is found to be a major factor for the extremely high water level in the mainstream during the 1998 Yangtze River flood. Subsequently the variations of discharge distribution and water level with channel parameters between each branch in this system were studied as well. As a result, flood evolution caused by Jingjiang River shortcut and sediment deposition in the entrance of dividing channels of the Yangtze River may be qualitatively elucidated. It is suggested to be an effective measure for flood mitigation to enhance regulation capability of reservoirs available upstream of the tributaries and harness branch entrance channels.     

A miniaturized flow-injection analysis ( μ FIA) system with on-line chemiluminescence detection for the determination of iron in estuarine water

A miniaturized flow-injection analysis system constructed from a glass base plate and polydimethylsiloxane (PDMS) top plate was employed for the determination of iron in river water. Two designs were investigated, one utilizing a syringe pump and the other utilizing EOF pumping with a mini-filtration system incorporated. The syringe pump system was used to optimize the analytical method on chip, where the pump was used to deliver both the analyte and the reagents to the reactor chip. The highly sensitive chemiluminescence reaction between alkaline luminol (3-aminophthalhydrazide) and 0.1?M of hydrogen peroxide (H₂O₂) in the presence of iron(II) was utilized. The bright blue light (λ _max?～?440?nm) emitted was detected using a miniaturized photomultiplier tube interfaced directly under the chip. The light intensity signals were recorded, and the corresponding concentration of iron(II) concentration was determined. The calibration for iron(II) standards was linear up to 0.75?µg?mL^?1 (y?=?5.7839x?+?0.0378, r² ?=?0.9939) with a precision value of up to 3.72% RSD, for n?=?3. The limits of detection (blank?+?3s _y/x) were found to be 28?ng?mL^?1. The system which utilized EOF pumping and incorporated a minifiltration unit provided a linear calibration for 0–5?µg?mL^?1 (y?=?3.316x?+?0.1831; correlation coefficient, r ²?=?0.9996) over a working range of 0.0–0.5?µg?mL^?1. This system provided lower limits of detection 5.1?ng?mL^?1 and better repeatability (%RSD less than 0.5% for n?=?4), but problems occurred with the mini-filtration system at higher iron(II) concentrations. The EOF pumping system provided slightly higher results for the concentration of iron(II) in the Humber estuary (0.058?µg?mL^?1), but these results were in line with the results expected by the Environment Agency.     

Fit-for-Purpose Assessment of QuEChERS LC-MS/MS Methods for Environmental Monitoring of Organotin Compounds in the Bottom Sediments of the Odra River Estuary

Organotin compounds (OTCs) are among the most hazardous substances found in the marine environment and can be determined by either the ISO 23161 method based on extraction with non-polar organic solvents and gas chromatography analysis or by the recently developed QuEChERS method coupled to liquid chromatography-mass spectrometry (LC-MS/MS). To date, the QuEChERS LC/MS and ISO 23161 methods have not been compared in terms of their fit-for-purpose and reliability in the determination of OTCs in bottom sediments. In the case of ISO 23161, due to a large number of interferences gas chromatography-mass spectrometry was not suitable for the determination of OTCs contrary to more selective determination by gas chromatography with an atomic emission detector. Moreover, it has been found that the derivatization of OTCs to volatile compounds, which required prior gas chromatography determination, was strongly affected by the sediments’ matrices. As a result, a large amount of reagent was needed for the complete derivatization of the compounds. Contrary to ISO 23161, the QuEChERS LC-MS/MS method did not require the derivatization of OTC and is less prone to interferences. Highly volatile and toxic solvents were not used in the QuEChERS LC-MS/MS method. This makes the method more environmentally friendly according to the principles of green analytical chemistry. QuEChERS LC-MS/MS is suitable for fast and reliable environmental monitoring of OTCs in bottom sediments from the Odra River estuary. However, determination of di- and monobutyltin by the QuEChERS LC-MS/MS method was not possible due to the constraints of the chromatographic system. Hence, further development of this method is needed for monitoring di- and monobutyltin in bottom sediments.     

新阶段长三角一体化发展须处理好几类关系

作为中国经济活力最强、发育最为成熟的城市群之一,长三角具备坚实的经济基础和特点鲜明的区域合作模式,是中国最有条件实现现代化和一体化的区域。以上升为国家战略为标志,长三角一体化进入了新阶段。基于新阶段这一战略判断和长三角承担的新使命,长三角一体化须妥善处理好“质与量”“大与小”“同与异”“条与块”等几类关系：（1）质与量并行,以经济集聚提高发展效率;（2）大与小分明,全方位、立体化有序推进一体化国家战略;（3）同与异统一,以功能协同引导城市差异化、特色化发展;（4）条与块串联,以交通经济带建设推动都市圈等块状经济融合发展。     

Activities of idol immersion leads to heavy metal contamination in river Hooghly in and around the city of Kolkata

West Bengal is a rich cultural state for a number of religious festivals. One of the most important festival is Kali Puja and Diwali. Idol is supposed to be the image of God which is used for worship. After worshiping immersion of idols took place in the various Ghats of the river. Several accessories of worship such as flowers, food offerings, plastic sheets, polythene bags etc. are also poured in water. Materials of idols consist of clay, plaster of Paris, varnish, oil paint etc. These paints are highly pigmented and consist of white lead, lithopone, chrome yellow, cadmium sulphide, barium chromate, vermillion, red lead etc. heavy metal salts. This study is an attempt to assess the change in water quality before and after the immersion of idols giving emphasis on heavy metal. The above investigation were carried out by collecting the water samples from six immersion ghats of the river Hooghly before & after immersion of Kali idols of the year 2019 followed by the analysis of the different parameters of water. Investigation reveals a significant changes in heavy metal concentration between pre and post immersion of the idols. A pollution due to the idols immersion into the water bodies cause adverse effect to the aquatic life or entire ecosystem.Use of natural dyes for idols obtained from flowers, leaves roots of plants, wood, seeds may reduce this pollution to a significant level. Moreover, awareness among the people of the society may have a significant responsibility in controlling this pollution satisfactorily.     

The change of characteristics of tidal wave in the Changjiang River mouth area since the post-glacial transgression maximum

During the period of the post-glacial transgression maximum (PGTM), there was a huge trumpet estuary in the modern Changjiang River Delta area. The location and the shape of the Paleo-Changjiang River Estuary (PCRE) were much different from those of the present Chang-Jiang River Estuary. The study on the change of characteristics of tidal wave in the Changjiang River mouth area since the PGTM can help to understand better the dynamic development of the Changjiang River Delta. The course curves of tidal level and tidal current velocity during a single tidal cycle for 35 points are calculated, and characteristics of tidal waves in the PCRE and its adjacent area are compared with those of tidal waves in the modern Changjiang River mouth area. The results show that the tidal waves within the PCRE and in its adjacent area during the period of the PGTM belonged to standing wave or a mixture of standing wave and progressive wave. Since then, the tidal wave in the Changjiang River mouth become gradually to be pr