基于CBERS-02卫星数据的地震滑坡识别——以青川县为例

以5.12地震后四川省青川县为研究区域,以该区域CBERS-02 CCD数据及DEM数据为基础数据,结合国内外滑坡遥感识别数据处理方法,通过九个特征指标(CBERS-02 CCD五个波段、亮度、绿度、湿度及坡度)组合对青川县进行滑坡识别。首先经过镶嵌裁剪得到研究区影像图,用1、2、3波段合成真彩色图像,对该区域遥感影像滤波增强处理,减少图像斑点,改善图像质量,同时应用穗帽变换生成研究区的亮度、绿度、湿度指标;然后结合地震滑坡分布的地质地貌、构造岩性、形状纹理特点,对九个特征指标进行最大似然法监督分类;最后利用青川县的现场调查资料,对该滑坡识别结果进行了验证,同时结合滑坡发生的机理对滑坡分布进行了分析。研究区域的滑坡分布具有以下特点:1)分布范围广泛,且河谷两岸较多;2)地震产生的滑坡大多发生在坡度40°～50°、海拔700～1 100 m的山坡上。研究结果表明,利用中巴卫星进行滑坡识别的分类精度为76.4676%,Kappa系数为0.7130,抽取初步识别的96个滑坡进行野外校验,正确率为89%。证明中巴卫星适应于山区地震滑坡的识别。     

Growth and photosynthesis responses of Phaeodactylum tricornutum to dissolved organic matter from salt marsh plant and sediment

The effects of allochthonous dissolved organic matter (DOM) on the growth and photosynthesis of Phaeodactylum tricornutum were investigated. P. tricornutum incubated in f/2 medium was exposed to DOM additives, which were extracted from the plant and sediment samples of a salt marsh in North Branch of the Yangtze estuary, China. During 12 days incubation, the chlorophyll fluorescence parameters of P. tricornutum were measured by a Phyto-PAM phytoplankton analyzer. Spectral properties of DOM in algae filtrates were also observed. The concentrations of chlorophyll a, active chlorophyll a, and the maximum quantum yield of photosystem II significantly decreased after four days of incubation, suggesting that the growth and photosynthetic e ciency of P. tricornutum were inhibited. After adding sediment-DOM extract, both a250/a365 (the ratio of the absorption coe cients at 250 and 365 nm) and S values (spectral slope coe cients) of algae filtrates declined in the first two days, which demonstrated a loss of low molecular weight DOM. Parallel factor analysis of fluorescence spectra of DOM in algae filtrates revealed that DOM could be classified into two humic-like and two protein-like components. The fluorescence intensity of tyrosine-like component originating from algae increased significantly during incubation. This study supports the hypothesis that allochthonous DOM derived from salt marsh plant and sediment have a strong influence on the adjacent aquatic ecosystems.     

Phytoplankton community from Lake Taihu, China, has dissimilar responses to inorganic and organic nutrients

To evaluate the response of phytoplankton from Lake Taihu to di erent types of nutrients, the phytoplankton responses were measured after adding inorganic nitrogen (N) and phosphorus (P) or decomposed algal scum (Microcystis spp.) into the lake water. Both types of nutrients promoted an increase in phytoplankton biomass as determined by chlorophyll a and algal wet weight. The addition of decomposed algal scum resulted in a significantly greater phytoplankton response than the addition of inorganic N and P alone. The dissolved inorganic N and P in the inorganic nutrient treatment were found not limit phytoplankton growth. The higher algal biomass obtained in the treatment with decomposed algal scum indicated the importance of other organic nutrients besides N and P such as trace elements, as well as the importance of the form of N since the levels of ammonia nitrogen (NH4 +-N) from the decomposed algal treatment were actually higher than that of the inorganic N and P addition. Microcystis spp. (Cyanobacteria), Scenedesmus spp. (Chlorophyta) and Synechocystis spp. (Cyanobacteria) were the dominant taxa in the control, inorganic N and P treatment, and the decomposed algal scum treatment, respectively. Microcystis never bloomed in response to both types of nutrient additions indicating that the bloom propagation is not solely related to nutrient additions, but may be related to the absence of selective grazing from zooplankton.     

Classification of di erent sustainable flood retention basin types

Using a revised version of a previously published expert classification system, a database of potential Sustainable Flood Retention Basins has been developed for Scotland. The research shows that the majority of small and former (often old) drinking water reservoirs are kept full and their spillways are continuously in operation. Utilising some of the available capacity to contribute to flood control could significantly reduce the costs of complying with the European Union Flood Directive. Furthermore, the application of a previously developed classification model for Baden in Germany for the Scottish data set showed a lower diversity for basins in Scotland due to less developed infrastructure. The classification system appears to be robust and has the potential, with minor modifications, to be applied across Europe. The principle value of this approach is a clear and unambiguous categorisation, based on standard variables, which can help to promote communication and understanding between stakeholders.     

国际化学危险品分类体系简介

介绍了当前国际化学危险品的各种分类体系,对比了GHS与TDG、EU_CLP、DOT、WHMIS等对化学危险品的具体分类。有助于GHS的理解与掌握,全面推进GHS在我国的实施。     

大气环境腐蚀性分类分级研究综述

介绍了大气环境腐蚀性分类分级的发展状况、方法和作用,归纳了现有大气环境腐蚀性分类分级方法在等级划分、影响因素等方面存在的不足,展望了大气环境腐蚀性分类分级研究的发展趋势,并指出了开展针对高分子材料的大气环境老化严酷度分类分级研究的重要意义。     

深圳红树林水体浮游植物多样性与营养状态评价

通过监测深圳福田红树林水体浮游植物,掌握浮游植物多样性组成和时空分布特征,并利用浮游植物群落多样性指数结合生物量、数量,对水体营养状态进行评价。结果表明,浮游植物种类少,数量大。硅藻分布广泛,在种类和数量上占主导地位,优势种为微小小环藻(Cyclotella caspia)和诺氏海链藻(Thalassiosira nordenski ldi)等,一些耐污染的藻类,如小颤藻(Oscillatoria minima)、裸藻(Euglenaspp.)在特定季节成为一些站位的优势种。浮游植物种类组成时空变化显著,而数量的空间变化明显,季节差异不大。检测出富营养化指示种15种,中营养化指示种11种,贫营养化指示种9种。浮游植物的生物评价指数显示,深圳红树林水体处于中~富营养化状态,有向富营养化过渡的趋势,水体遭受严重污染,应注意加强对内陆径流和污水排放进入红树林的严格控制和管理。     

不同营养水平下苦草对附着和浮游藻类的影响

通过室内培养,研究了不同营养盐浓度下苦草对附着藻类和浮游藻类的影响,同时比较了两种藻类对不同营养盐浓度的响应,结果发现附着藻类在中高营养盐浓度下生物量较高而浮游藻类在中低营养盐浓度下生物量较高,虽然两者对营养盐的响应不一致,但其最大量都出现在中高浓度的营养盐状态下。在中低营养盐浓度下(ρTN=0.4～2.5mg/L),苦草促进附着藻类而抑制浮游藻类,即相比于浮游藻类而言,附着藻类对苦草的敏感性较低。在较高营养盐浓度(ρTN=4.5～6.5mg/L)下,苦草对附着藻类产生了极显著的抑制作用,且这种抑制作用随着营养盐浓度的增加而增强,在ρTN=6.5mg/L的处理条件下,苦草对附着藻类的抑制率近80%,但是在此营养盐浓度处理下,苦草对浮游藻类的抑制作用却减弱甚至消失了。     

Enhancement of formaldehyde degradation by amine functionalized silica/titania films

Doping amine functional groups into SiO2/TiO2 films for enhancing the decomposition of formaldehyde has been investigated using the modified sol-gel method to prepare organic-inorganic hybrid photocatalysts via the co-condensation reaction of methyltrimethoxysilane (MTMOS) and amine functional groups. n-(2-Aminoethyl)-3-aminopropyl-trimethoxysilane (AEAPTMS) and 3-aminopropyl-trimethoxysilane (APTMS) were selected to study the e ect of amine functional groups on the enhancement of formaldehyde adsorption and degradation under a UV irradiation process. Physicochemical properties of prepared photocatalysts were characterized with nitrogen adsorption-desorption isotherms measurement, X-ray di raction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. The results indicated that the APTMS/SiO2/TiO2 film demonstrated a degradation e ciency of 79% superior to those of SiO2/TiO2 and AEAPTMS/SiO2/TiO2 films due to the synergetic e ect of adsorption and photocatalytic properties. The APTMS/SiO2/TiO2 film can be recycled with about 7% decreasing of degradation e ciency after seven cycles.     

废旧塑料的简易分类方法

塑料制品因其具有质量轻、外观美、加工方便、经济实用等特点而颇受人们青睐,广泛用于各行各业和日常生活用品中,但塑料制品的大量使用也给环境造成了严重污染,消除塑料污染的最积极的办法是对废旧塑料进行回收再利用。塑料种类繁多,不同类别的塑料性质和用途都不相同。介绍几种塑料分类的简易方法,以利于废旧塑料的回收利用。