对构建水污染防治社会共治体系的分析与探讨——对《水污染防治行动计划》的解读

文章针对我国目前环境管理中存在的政府管理不到位、企业治污不履责和公众参与不够的问题,从政府、公众和企业方面梳理了国外水污染防治社会共治方面的主要经验,指出了我国水污染防治社会共治的重点,即明确政府责任、落实企业排污责任、构建全民行动格局。     

A new method for the prediction of flash points for ternary miscible mixtures

The flash point is one of the most important physicochemical parameters used to characterize the fire and explosion hazard for flammable liquids. The flash points of ternary miscible mixtures with different components and compositions were measured in this study. Four model input parameters, being normal boiling point, the standard enthalpy of vaporization, the average number of carbon atoms and the stoichiometric concentration of the gas phase for mixtures, were employed and calculated based on the theory of vapor–liquid equilibrium. Both multiple linear regression (MLR) and multiple nonlinear regression (MNR) methods were applied to develop prediction models for the flash points of ternary miscible mixtures. The developed predictive models were validated using data measured experimentally as well as taking data on flash points of ternairy mixtures from the literature. Results showed that the obtained average absolute error of both the MLR and the MNR model for all the datasets were within the range of experimental error of flash point measurements. It is shown that the presented models can be effectively used to predict the flash points of ternary mixtures with only some common physicochemical parameters.     

Influence evaluation of ionic liquids on the alteration of nitrification waste for thermal stability

Nitrification waste (NW) is the processed product of nitro compounds, flammable and explosive, and is prone to accidents due to thermal runaway. Ionic liquids (ILs) are widely used as flame retardants and have a good inhibitory effect. The effect of 1-butyl-3-methylimidazole hexafluorophosphate and 1-butyl-3-methylimidazole tetrafluoroborate as humectants on the thermal stability of NW was investigated in this paper. The microstructure and properties of the ionic liquid hybrid NW were first investigated using scanning electron microscopy. Secondly, thermogravimetric experiments were carried out on the ionic liquid mixed NW by thermogravimetric-infrared spectroscopy to analyze the decomposition law. Finally, six advanced linear regression thermokinetic models were used to calculate its apparent activation energy, pre-exponential factor, and other thermokinetic parameters, and the reaction model was simulated through multiple linear regression. The experimental research results in this paper can provide a reference for the storage and disposal of nitro compounds and their wastes.     

南通市深层地下水中氨氮的影响因素研究

运用相关性分析、因子分析及多元线性回归模型对南通市2020—2021年15个监测井第Ⅲ承压层地下水的监测数据进行分析,研究深层地下水中氨氮的主要影响因素。结果表明,氨氮的主要来源是地下水沉积物中有机质的矿化及一部分工业开采引入的氮污染,地下水的还原性环境是氨氮赋存的主要成因;地下水中As、Fe及总硬度含量的同时增加也能反映氨氮含量的提高;硝态氮（NO-3-N）与NH3-N在深层地下水中是竞争关系,当地下水环境处于还原性时,更易于NH3-N的富集。降低深层地下水中氨氮的主要方法是减少有机污染物输入及还原性废水的入渗。     

The importance of white on black: unmelanized plumage proportion predicts display complexity in birds

Animal ritualized displays have been classically viewed as behavioral characters that decrease signal ambiguity or that facilitate the evaluation of costly exhibitions. It has been shown that their prevalence and level of complexity across species can reflect phylogenetic relationships between them, but the adaptive function of these behavioral traits is poorly known. Here, I hypothesize that, given that the efficacy of visual displays basically depends on conspicuousness and level of performance, species with low levels of conspicuousness may be forced to perform more complex varieties of a given display to get the same signal efficiency than other more conspicuous species. Thus, the evolution of display complexity, considered as the level of exaggeration of ritualized movements, may be explained as an adaptive trait and not only by phylogenetic inertia. I illustrate and test this hypothesis with the case of black-and-white plumage patches of pelecaniform birds. As predicted, there was a negative correlation between level of complexity and species conspicuousness (proportion of unmelanized plumage) for two different social displays. This indicates that classical ideas on the adaptiveness of ritualized displays should be considered to understand the present variation in signal form across species, which sheds light on the evolution of multiple signals.     

基于遥感数据的京津冀地区PM2.5时空分布特征

基于MODIS AOD遥感数据,采用多元线性回归模型对PM2.5地面监测数据进行模拟估算,同时加入降水量、相对湿度等气象因子以提高模型精度,结合GIS空间分析技术,得到2015—2016年京津冀地区空间连续的PM2.5浓度分布。结果表明:利用多元线性回归模型反演PM2.5浓度效果较好,R 2均在0.59~0.84之间。在时间上,京津冀地区PM2.5浓度呈现出夏季最低、秋季稍高、冬春两季最高的变化趋势;在空间上,2015年和2016年京津冀地区PM2.5浓度有明显的区域差异,均呈现出西北低、东南高的分布格局,大致与燕山山脉和太行山脉走向一致。     

Local Responses to Inundation and De-Farming in the Reservoir Region of the Three Gorges Project (China)

Large-scale infrastructural developments in rural areas often impose significant direct and indirect impacts on environment and people. The Three Gorges Project to dam the Yangtze River in China will create a huge reservoir, inundate farmlands and villages, and incur large-scale resettlement. The concurrent de-farming program to reforest marginal farmlands on steep slopes imposes additional stresses on local people. This study evaluates the ecological and economic adjustments in rural areas affected by both projects, and explores villagers’ knowledge, attitudes, perceptions, and expectations vis-à-vis the drastic changes. Eleven villages in Yunyang County in Sichuan Province, stratified into three zones based on topography and agriculture, were assessed by field studies, questionnaire surveys, maps, satellite imagery, and census and government reports. Multiple regressions identified predictors for 17 dependent variables. Spatial variations in the difficult terrain imposed zone-differentiated agricultural constraints, ecological impacts, and human responses. The dominant farming population—mainly young adults working as migrant laborers in cities—has adopted some nonagricultural work to supplement incomes. Expected per-capita standardized farmland (SF) exceeded threshold SF, which surpasses existing SF. Motivations to reclaim more farmlands, de-farm marginal lands, and become migrant laborers were explained by different multiple-regression predictors. Reduction in farmland stock by inundation and de-farming, aggravated by unwillingness towards nonlocal resettlement, would impose ecological pressures and stimulate demands for nonfarming incomes. Common anticipation of better future income and occupation has been subdued by unfavorable feedbacks from early relocatees. Future environmental and landscape changes are hinged upon changing human responses. Government policies could be informed by research findings to match economic, ecological, and social realities.     

Juggling Land Retirement Objectives on an Agricultural Landscape: Coordination, Conflict, or Compromise?

Strategic land retirement in agricultural settings has been used as one way to achieve a combination of social objectives, which include ameliorating water quality problems and enhancing existing systems of wildlife habitat. This study uses a simulation model operating on a virtual landscape, along with the compromise programming method, to illustrate the implications of alternative weighting schemes for the long-term performance of the landscape toward various objectives. The analysis suggests that particular spatial patterns may be related to how various objectives are weighted. The analysis also illustrates the inevitable trade-offs among objectives, although it may be tempting to present retirement strategies as “win-win.”     

Performance Evaluation of the SLEUTH Model in the Shenyang Metropolitan Area of Northeastern China

Performance evaluation is crucial for the development and improvement of an urban cellular automata model, such as SLEUTH. In this paper, we employed multiple methods for map comparison and model validation to evaluate the simulation performance of the SLEUTH urban growth model in the Shenyang metropolitan area of China. These multiple methods included the relative operating characteristic (ROC) curve statistic, multiple-resolutions error budget, and landscape metrics. They were used to quantitatively examine model performance in terms of the amount and spatial location of urban development, urban spatial pattern and prediction ability. The assessment results showed that SLEUTH performed well in the way of the quantitative simulation of urban growth for this case study. Similar to other urban growth models, however, the simulation accuracy for spatial location of new development at the pixel scale and urban spatial pattern still needs to be improved greatly. These inaccuracies might be attributed to the structure and nature of SLEUTH, local urban development characteristics, and the temporal and spatial scale of its application. Finally, many valuable suggestions had been put forward to improve simulation performance of SLEUTH model for spatial location of urban development in the Shenyang metropolitan area.     

梅梁湖水体浮游植物与环境因子的关系

根据2008年的4月—11月梅梁湖水域应急监测数据,探讨了梅梁湖水体浮游植物与环境因子的关系。相关性分析结果表明,蓝绿藻含量与TP、pH值和DO呈极显著正相关;与TN、SD和EC呈极显著负相关;与NH3-N呈显著负相关。多元逐步回归分析结果表明,梅梁湖浮游植物生长受多个环境因子的共同影响,但主要为TP、TN、水温和风速。