滇池流域不同土壤类型和土地利用方式的土壤中溶解性有机碳的流失特性研究

采集滇池流域不同土壤类型、不同土地利用方式下的土壤样品,进行土壤中溶解性有机碳(DOC)的静态解吸实验,通过测定不同时间下溶入水相的COD量,探究不同土壤类型及土地利用方式下DOC的流失特性,从而揭示不同土地利用方式对滇池流域面源污染的影响.结果表明,同一土地利用方式的不同类型土壤中DOC的溶出平衡时间为壤土＞粘土＞粘壤土,其中退耕区(粘壤土＞粘土＞壤土)、大棚(粘土＞粘壤土=壤土)土壤不符合该规律,溶出平衡时间基本为1.5～2.5h;不同的土壤类型和土地利用方式下,DOC的溶出率为1.00％～2.75％,同一土地利用方式的不同类型土壤中DOC的溶出率存在一定差别,这是由于不同类型的土壤中砂粒、粉粒、粘粒的含量有所差异.     

Halotolerant bacteria of the genus <Emphasis Type="Italic">Arthrobacter</Emphasis> degrading polycyclic aromatic hydrocarbons

Eight strains of bacteria capable of degrading polycyclic aromatic hydrocarbons have been isolated from soils and bottom sediments sampled in the region of Verkhnekamskoe potash deposit (Berezniki, Perm krai) and classified with the genus Arthrobacter on the basis of phylogenetic analysis (16S rRNA genes) and morphological and chemotaxonomic characters. According to the results of 16S rDNA sequence alignment, strains B905, SMB11, SMB145, SF27, and DF14 show the highest sequence homology to the type strain of A. crystallopoietes (99.7%), and strain SN17, to the type strain of A. arilaitensis (99.8%). The isolated strains are capable of growing on naphthalene and phenanthrene (as the sole sources of carbon and energy) in the presence of 60 mg/l NaCl. Their cells contain large plasmids ranging in size from 85 to 130 kb. Plasmid elimination from Arthrobacter sp. SF27 has proved to result in the loss of capacity for growing on naphthalene and phenanthrene, suggesting a plasmid localization of genes responsible for degradation of these compounds.     

Nanoflower synthesis,characterization and analytical applications: a review

Environmental Chemistry Letters - The occurrence of contaminants in the environment requires very sensitive analytical techniques for their determination. For that, analytical techniques have been...     

国家环境信息数据库的研究

本文概述了国家“七五"科技攻关“国家环境信息数据库研究"课题的研究背景,研究方法及该课题的研究成果“国家环境信息系统"的总体结构、规模、系统的主要功能以及该系统“八五"继开发的设想。      

淮河上游全新世古洪水沉积学特征及古洪水事件气候背景

通过详细的野外调查,在淮河上游的毛集河口发现了夹有一套淮河古洪水滞流沉积物层的黄土-古土壤剖面。对剖面进行详细观察、分层和取样,并对样品做粒度和化学元素分析,通过OSL测年进行控制点断代,进一步对该流域洪水事件与全球厄尔尼诺现象进行对比。结果认为：自8500a以来,在淮干上游至少发生了6次特大洪水,与厄尔尼诺现象有明显的响应关系。通过对沉积物不同粒级的组分含量对比,认为SWD在粗粒级范围为优势组分,而黄土古土壤在细粒级范围为优势组分,据此可以有效地对古洪水沉积物层加以识别。地球化学分析表明,剖面不同沉积单元上化学元素呈现出鲜明差异,表现为在SWD中SiO2和Th明显贫化,Fe2O3、CaO、MgO、P、V、Sr、Nb富集,Al2O3、Na2O、K2O、Cr、Zn、Rb在剖面各地层单元中没有表现出明显的区别,通过地球化学元素的富集或贫化特征亦可以很好地识别古洪水滞流沉积物层。通过对古洪水沉积物的识别得到了全新世以来淮河上游特大洪水信息,也一定程度上能够从沉积学角度佐证在该流域特大洪水的发生与全球厄尔尼诺现象密切相关。     

兼顾生态系统功能和生态需求强度的城市生态用地重要性评价——以长沙市为例

生态环境保护和城市经济发展的矛盾由来已久,科学评价生态用地的重要性,对维护区域生态安全和引导城市有序扩张具有重要意义。生态用地的重要性不仅由生态用地自身的生态系统功能决定,同时受到人类生态需求强度的影响。选取生物多样性维持功能、土壤保持功能、水源涵养功能、户外休闲需求和生态用地稀缺度等指标,以长沙市中心城区为研究区,构建了兼顾生态系统功能和区域生态需求强度的生态用地重要性评价模型,进行了生态用地重要性评价。其中,生态系统功能通过生物多样性维持功能、土壤保持功能、水源涵养功能量化,区域生态需求强度通过户外休闲需求和生态用地稀缺度量化。实验结果表明：长沙市中心城区生态用地空间分布差异显著,极重要生态用地主要由大面积集中连片的森林、重要饮水源地和高质量的耕地构成,既包括城市外围提供生态屏障的大块生态用地,同时包括人口稠密城市建成区内的湿地、河流等小面积生态用地。与传统评价模型相比,构建的模型能够体现人类需求的影响,结果更符合人们的实际生态需要。     

Genetic Differentiation of the Ural Endemic <Emphasis Type="Italic">Gypsophila uralensis</Emphasis> (Caryophyllaceae) in Relict Fragments of Its Range in Northwestern European Russia

Molecular genetic methods (AFLP and ITS1–5.8S–ITS2 rDNA analysis) have been used to study the level and structure of genetic diversity in relict populations of the Ural endemic Gypsophila uralensis Less. in the northeast of European Russia. Intraspecific genetic differentiation is most clearly manifested between G. uralensis Less. subsp. pinegensis (Perf.) Kamelin locally endemic to the north of Europe (Arkhangelsk oblast, locus classicus) the population of G. uralensis Less. subsp. uralensis on limestone outcrops along the Shchugor River, the Subpolar Urals. The cluster of Timan populations (on limestone outcrops along the Svetlaya, Pizhma, and Myla rivers) is autonomous and genetically heterogeneous. Genetic distances between model G. uralensis s.l. populations are correlated with geographic distances. The size and abundance of relict populations show a descending gradient in the forest zone, and parameters of their genetic diversity [1] and unbiased expected heterozygosity have been found to decrease along this gradient.     

Concentration and size distribution of particulate matter in a new aviary system for laying hens in China

ABSTRACT

Particulate matter (PM) from poultry production facilities may strongly affect the health of animals and workers in the houses, and PM emitted to the ambient air is an important pollution source to the surrounding areas. Aviary system is considered as a welfare friendly production system for laying hens. However, its air quality is typically worse as compared with conventional cage systems, because of the higher PM concentration of indoor air and other airborne contaminants. Furthermore, PM’s physical property, which has a direct impact on the penetration depth into the lungs of the birds and humans, is largely unknown for the aviary system. Therefore, a systematic method was utilized to investigate the characteristics of particles in the aviary house with large cage aviary unit system (LCAU) in Beijing, China. For the field measurements, three measuring locations were selected with two inside and one outside the house with LCAU to continuously monitor PM concentrations and collect the samples for particle size distribution (PSD) analysis. Results showed that PM_2.5, PM₁₀, and total suspended particulate (TSP) concentrations averaged at 0.037 ± 0.025 mg/m³, 0.42 ± 0.10 mg/m³, and 1.92 ± 1.91 mg/m³, respectively. Particle concentrations increased from October to December due to less ventilation as the weather got colder, and were generally affected by stocking density, ventilation rate, birds’ activities, and housing system. Meanwhile, indoor PM_2.5 concentration was easily impacted by the ambient air quality. Mass median diameter (MMD) and mass geometric standard deviation (MGSD) of the TSP during the measurement were 18.92 ± 7.08 μm and 3.11 ± 0.31, respectively. Count median diameter (CMD) and count geometric standard deviation (CGSD) were 1.94 ± 0.14 μm and 1.48 ± 0.08, respectively. Results indicated that the aviary system can attain a good indoor condition by suitable system design and environment control strategy.

Implications: Indoor PM_2.5 concentration of the layer house can be significantly affected by ambient air quality when the air quality index (AQI) was larger than 100. PM_2.5 and PM₁₀ concentrations of the layer house with a LCAU system were comparable to the cage system. TSP concentration was higher, and PM size was larger than most of the cage system. System design, larger space volume, and higher ventilation rate were the main influence factors. Good indoor environment of the aviary system can be achieved through the reasonable design of the production system and appropriate environment control strategy.     

旅游景区解说设施研究

为了更好地促进旅游信息的传播与交流、旅游地形象的宣传、旅游学术思想的交流与共享、旅游产品的促销、旅游服务的完善与提高等,对旅游景区解说设施的功能、类型、解说效果、相关因素、流程进行了深入研究,提出了旅游景区解说设施的4个功能、2大类型,比较分析了各类型旅游解说设施的解说效果、解说设施及其相关要素的循环关系,以及旅游景区解说设施的规划流程。     

固氮植物篱改善退化坡耕地土壤养分状况的效果

在四川宁南县坡地农业实验站对固氮植物篱在坡耕地上防治水土流失和改良土壤的效果进行了长期定位研究．结果表明等高固氮植物篱在防治土壤养分退化方面效果明显：与传统顺坡种植（ＣＫ） 相比,在坡耕地上培植新银合欢（Ｌｅｕｃａｅｎａｌｅｕｃｏｃｅｐｈａｌａ） 等高植物篱和山毛豆（Ｔｅｐｈｒｏｓｉａ ｃａｎｄｉｄａ）等高植物篱,正常耕作３～６ ａ 后,作物带土壤全氮可增加８０％ ～１３０％ ,有机质增加２０％ ～４０％ ,有效钾和阳离子交换量等养分均有不同程度增加．由于肥力状况改善,等高植物篱处理的农作物产量也明显高于ＣＫ．