淮安市农产品中重金属及有机氯、有机磷农药残留量调查

淮安市环境监测中心站于1999年－2000年对淮安市农产品中重金属以及有机氯、有机磷农药残留量进行了调查。结果表明，粮食和蔬菜作物中，六六六的4种同分异构体只有γ－六六六能检出，检出率分别为24．0％和51．7％，都未超标；DDT的4种同分异要体均未检出；有机磷农药的检出率分别为5％和25％，其中蔬菜中敌敌畏含量出现个别超标现象，倍硫磷、乐果和杀螟松在粮食和蔬菜作物中的含量都不超标。重金属中金属“五毒”在粮食和蔬菜作物中，只有Cr和Pb能检出，Cd、Hg和As都未检出，Cu、Zn和Mn能检出，但不超标。提出，应严格按照农牧渔业部和卫生部颁发的《农药安全使用规定》用药，多使用高效低残留量的“绿色农药”；农业、环保和卫生部门必须加强合作，对蔬菜生产销售的全过程进行监督监测，以确保生产无公害蔬菜。     

Remote sensing: Using the spatial domain

Objects in the terrestrial environment interact differentially with electromagnetic radiation according to their essential physical, chemical and biological properties. This differential interaction is manifest as variability in scattered radiation according to wavelength, location, time, geometries of illumination and observation and polarization. If the population of scattered radiation could be measured, then estimation of these essential properties would be straightforward. The only problem would be linking such estimates to environmental variables of interest. This review paper is divided into three parts. Part 1 is an overview of the attempts that have been made to sample the five domains of scattered radiation (spectral, spatial, temporal, geometrical, polarization) and then to use the results of this sampling to estimate environmental variables of interest. Part one highlights three issues: first, that relationships between remotely sensed data and environmental variables of interest are indirect; second, our ability to estimate these environmental variables is dependent upon our ability to capture a sound representation of variability in scattered radiation and third, a considerable portion of the useful information in remotely sensed images resides in the spatial domain (within the relations between the pixels in the image). This final point is developed in Part 2 that explores ways in which the spatial domain is utilized to describe spatial variation in remotely sensed and ground data; to design optimum sampling schemes for image data and ground data and to increase the accuracy with which remotely sensed data can be used to estimate both discontinuous and continuous variables. Part 3 outlines two specific uses of information in the spatial domain; first, to select an optimum spatial resolution and second, to inform an image classification.     

The Valuation of Health Effects Caused by Stationary Sources–Related SO2 Emissions: The Adaptation of Impact Pathway Approach in Taiwan

This paper presents the externalities of sulfur dioxide (SO₂) in the Taichung metropolitan, Taiwan. The human effects of SO₂ from stationary sources are a key element for local air quality management. A methodology to evaluate those effects in monetary term had been adapted and applied. This method was modified from the EU-based impact pathway approach link to the skill of geographic information systems. The studied area was divided into 66 districts and the quantity of SO₂ was allocated to each district. Then, the ambient concentration of SO₂ was estimated by using the ordinary kriging method. A risk analysis was employed to characterize the health impacts caused by SO₂. Finally, a monetary transfer approach based on the European data was conducted to estimate local damage costs per ton of SO₂. Health impacts, especially acute mortality, dominate in term of costs. The calculation showed that damage costs ranged from 0.56 to 7.38 USD/kg SO₂ based on the 2002 emission data. The results could be used in the internalization of SO₂ externalities and management of the stationary sources in the studied area. This paper also concludes that the externalities caused by stationary-related SO₂ emissions are some 28.5 million US dollars in Taichung metropolitan (Taiwan) in 2002.     

Minimization of the environmental impact of chrome tanning: a new process with high chrome exhaustion

In all tanning technology operations wastes are generated. These reach the environment as residual waters, solid and liquid waste as well as atmospheric emissions and odours.

This study tests an alternative method to the traditional tanning method at an industrial level. The new method is based on tanning without float and by significantly increasing the temperature at the end of the tanning process. The properties of the leathers obtained using the two methods have been compared and the results indicate that those leathers have similar physical, chemical, and organoleptic properties. However, the differences existing from the environmental point of view are significant. It is not necessary to use clean water for this tanning. Moreover, there is a 75% reduction of the residual float, a 91% reduction of the chrome discharged, and a 94% reduction of the chlorides discharged. A financial assessment was carried out to demonstrate that the newly proposed system is 32% more economic than the traditional one.     

污染场地调查动态追补钻井点位的方法研究

污染场地中的污染区域较小,但污染物的空间变异性大,污染土体较深,因而在场地调查中通常需采集场地钻井数据进行三维模拟.为了准确估计场地土壤污染物的空间分布和需修复的污染土方量,提出了场地污染调查补充采样钻井点位布设的优化方法.在初始采样的基础上,首先利用克里格方法预测场地中土壤污染物的克里格方差,基于克里格方差估算置信度,再结合场地置信度和场地污染物含量的空间分布确定场地的最大不确定性点,并将该点作为下一阶段补充采样点,以实现逼近式动态追补钻井点位的布设.最后,以某硝基苯污染的工业场地为例对该方法进行验证.结果表明:场地中硝基苯的空间变异性大,增加采样点会显著减少基台值,提高研究区总体的置信度,同时减少总体的不确定性.在项目经费约束条件下,不确定性减少65%时,需要至少增加采样点10个.10个样点的增加使得总体估值方差降低了40%,同时总体的估计精度提高了22.4%.案例结果验证了该方法在单一类有机污染场地中的可行性和适用性,能够在保证场地污染调查精度的同时,显著降低样本量,实现场地调查的成本-效益最大化.     

Sorption and desorption of Cd, Cu and Pb using biomass from an eutrophized habitat in monometallic and bimetallic systems

This work examines the sorption capacity of a natural biomass collected from an irrigation pond. The biomass mainly consisted of a mixture of chlorophyte algae with caducipholic plants. Biosorption experiments were performed in monometallic and bimetallic solutions containing different metals commonly found in industrial effluents (Cd, Cu and Pb). The biosorption process was slightly slower in the binary system comparing with monometallic system which was related to competition phenomena between metal cations in solution. The biosorbent behaviour was quantified by the sorption isotherms fitting the experimental data to mathematical models. In monometallic systems, the Langmuir model showed a better fit with the following sorption order: Cu ~ Pb > Cd; and biomass-metal affinity order: Pb > Cd ~ Cu. In bimetallic systems, the binary-type Langmuir model was used and the sorption order obtained was: Pb ~ Cu > Cd. In addition, the effectiveness of the biomass was investigated in several sorption-desorption cycles using HCl and NaHCO(3). The recovery of metal was higher with HCl than with NaHCO(3), though the sorption uptake of the biomass was sensitively affected by the former desorption agent in subsequent sorption cycles.     

Ink and dirt behavior in pulping after artificial aging of cold-set offset printed newspapers in different humidity conditions

Although moisture has a decisive role in the permanence of cellulose and unprinted paper, its role in ink release from the surface of printed recovered papers remains unclear. This work aimed to determine whether various relative humidity levels in the artificial aging test affect ink release from the surface of the paper and its fibers when pulping cold-set offset printed newspapers in alkaline pulping conditions. The results showed that relative humidity variations from 30% to 70% negligibly affected ink release at 60 °C. However, compared with these lower humidity levels, exposure to 90% relative humidity for at least 25 h resulted in a higher ink content bound to fibers, a greater formation of visible dirt specks after pulping and a smaller formation of microscopic ink particles. In practical applications, the accurate estimation of climate effects during the storage and the transportation of recycled papers requires that humidity conditions are taken into account while performing artificial aging tests with paper products.     

Long-term dynamics of biomass production, soil chemical properties and plant species composition of alluvial grassland after the cessation of fertilizer application in the Czech Republic

The resilience, the ability of an ecosystem to recover after termination of perturbation, of highly productive Alopecurus grassland was investigated after the cessation of the following long-term fertilizer treatments applied under a two- or three-cut management regime: unfertilized control, PK, N₁₀₀PK, N₂₀₀PK, N₃₀₀PK and N₄₀₀PK. Annual application rates of pure nutrients per hectare were 0–400 kg for N, 40 kg for P and 100 kg for K. The dynamics of biomass production were measured for 16 years and the effect of former fertilizer treatments on soil chemical properties, biomass chemical properties, plant species composition and species richness were investigated 16 years after the last application of fertilizers. It was concluded that 16 years was not long enough to achieve resilience in plant-available soil P and K concentrations, N/P ratios in the plant biomass or plant species composition, but that it was long enough to achieve resilience in species richness. In the case of biomass production the effect of former fertilizer treatments was apparent in 10 of the 16 seasons investigated, indicating that resilience in biomass production must be evaluated using data from more than 1 vegetation season. The results of the study stress the necessity for long-term research because of high year-to-year variability in biomass production as well as long-term after-effects of fertilizer treatments in alluvial grassland.