华北平原夏收期间气溶胶卫星遥感探测分析

为研究2014年华北平原在夏收期间气溶胶污染的时空分布特征及形成原因,对2014年6月MODIS卫星的华北平原的气溶胶光学厚度(AOD)、细粒子比(FMF)、火点分布及后向轨迹进行了分析.结果表明,2014年6月华北平原的气溶胶光学厚度值在1.2~2.0之间,远高于年平均值1.0~1.2,而6月的火点分布主要集中在6—14日,此阶段的气溶胶光学厚度值高于6月6日前及14日以后的气溶胶光学厚度值.在两个特定研究区——华北南部及长三角地区,通过对6月的3个阶段的细粒子比进行分析,发现火点集中阶段细粒子排放增多,确定此次污染极有可能是由秸秆燃烧造成.在火点集中时期,两个研究区的后向轨迹说明,污染主要来自火点分布密集区域,进一步确定了秸秆燃烧是华北平原在夏收期间的主要污染源之一.     

On the functional extinction of the Passenger Pigeon

The Passenger Pigeon (Ectopistes migratorius) was a social breeder, and it has been suggested that the species experienced functional extinction, defined as a total reproductive failure, prior to its actual extinction in the early years of the 20th century. We applied a novel randomization test based on the relative times of the most recent egg‐ and skin‐specimen sightings (i.e., recorded date of specimen collection) to test for functional extinction. For a total of 6 eggs and 27 skins, the observed significance level was 0.38, which indicated that the species did not become functionally extinct. Thus, proposals to reverse its rapid decline in the late 19th century could have been successful.     

‘Ecomálaga’: an ecosystem analysis of the Mediterranean coast around Málaga, Spain

In October 1992, the Oceanographic Centre of Málaga of the Spanish Oceanographical Institute (IEO) started a monitoring project,Ecomálaga, which collects physical, chemical, biological and sedimentological data from the Alborán Sea shelf. The project is coordinated with similar projects in the Atlantic and Mediterranean Centres of IEO. The ultimate objective is to, understand the long-term changes of the essential marine-environmental parameters. So far, nine quarterly surveys have been carried out—from October 1992 to December 1994. The following variables were registered:abiotic: location weather, water temperature, salinity, pH, dissolved oxygen, chlorophyll a, nitrate, nitrite, phosphate, silicate,biotic: zooplankton biomass and species composition, and ichthyoplankton. The granulometric composition and organic matter content of sediments are also included. Data are stored in a computerized data base named Ecomálaga Data Base, with contributions from geology, physics, plankton biology and marine chemistry. The data base not only contains separate files for each research topic, but also allows for interchange between these files, resulting in a synoptic data output. It offers the users an output in the form of synthetic records of each station sampled. The analysis of the data indicates seasonal influences and ainshore-offshore gradient, as well as an Atlantic influence on the stations located in the transect closest to the Strait of Gibraltar.     

Evaluation of recycling waste materials and by-products in highway construction

SUMMARY

The generation, handling, and safe disposal of waste materials has become a major concern in North America. Approval of facilities for waste processing and proper disposal is becoming more difficult to obtain. Furthermore, there is a growing public awareness of the importance of conserving and preserving our valuable natural resources. This expanding awareness has given rise to the trend towards recycling or reuse of awide variety of solid wastes. Experiences with using waste materials in highway construction can vary considerably, depending on material characteristics, construction processes, and climatic differences. A number of waste materials may be suitable for use in highway construction, but others may not. The objective of this paper is introduced in two tasks. The first is to include a survey of the waste materials and by-products that have been used successfully, or may be used, as materials for highway construction or maintenance work. This also includes determination of the state of practice concerning economic and technical factors for these wastes. The second is to rank these materials based on three criteria: number of uses by State agencies, economic uses and performance aspects.     

High-Frequency Zone of River Desiccation Disasters in China and Influencing Factors

In recent years, the desiccation of the lower Yellow River has raised concerns in the government, public, and scientific community in China. Long-term and widespread desiccation of rivers is a disaster with many adverse environmental implications. It has been found in this study that there exists a high-frequency zone of river desiccation disasters at 34°–42°N in the North China Plain. The hazardous environment is characterized by semiarid climate, widely distributed thick loess in the basin and a “hanging river bed” in the plain as well as unfavorable man–water–land coupling relationships. In this setting, the sharply increased water diversion by man since the late 1950s led to the occurrence of river desiccation disasters in the lower reaches of the river in this area.     

Effects of Pioneer Tree Species Hyperabundance on Forest Fragments in Northeastern Brazil

Abstract: Despite many studies on fragmentation of tropical forests, the extent to which plant and animal communities are altered in small, isolated forest fragments remains obscure if not controversial. We examined the hypothesis that fragmentation alters the relative abundance of tree species with different vegetative and reproductive traits. In a fragmented landscape (670 km²) of the Atlantic Forest of northeastern Brazil, we categorized 4056 trees of 182 species by leafing pattern, reproductive phenology, and morphology of seeds and fruit. We calculated relative abundance of traits in 50 1‐ha plots in three types of forest configurations: forest edges, small forest fragments (3.4–83.6 ha), and interior of the largest forest fragment (3500 ha, old growth). Although evergreen species were the most abundant across all configurations, forest edges and small fragments had more deciduous and semideciduous species than interior forest. Edges lacked supra‐annual flowering and fruiting species and had more species and stems with drupes and small seeds than small forest fragments and forest interior areas. In an ordination of species similarity and life‐history traits, the three types of configurations formed clearly segregated clusters. Furthermore, the differences in the taxonomic and functional (i.e., trait‐based) composition of tree assemblages we documented were driven primarily by the higher abundance of pioneer species in the forest edge and small forest fragments. Our work provides strong evidence that long‐term transitions in phenology and seed and fruit morphology of tree functional groups are occurring in fragmented tropical forests. Our results also suggest that edge‐induced shifts in tree assemblages of tropical forests can be larger than previously documented.     

南水北调中线水源地汉江上游流域主要生态环境问题及对策

汉江上游是南水北调中线水源地，流域生态环境建设是保障水源地水质安全的关键。针对上游流域水环境污染、土地利用以及水土流失等重大生态环境问题，结合流域数字高程模型及水质调查对其进行了系统分析。结果表明：（1）丹江流域、库区流域及汉中盆地水质较差，CODMn和氨氮成为水源区主要污染物；（2）各子流域区植被覆盖占各自面积的712%~957%，表明流域植被覆盖较好，但沿河岸100 m范围内农业用地占292%~434%，且多为坡耕地；（3）流域水土流失严重，2000年左右流域侵蚀图显示汉江源头、秦岭南及大巴山北均出现了大片年均侵蚀模数>2 200 t/km2的区域，且有日益增强的趋势。提出加大水环境污染整治力度、加强农业用肥管理及河岸带建设、水土保持建设以及加强流域水环境及水土保持监测和科研工作等对策。     

Effect of Soils on Water Quantity and Quality in Piedmont Forested Headwater Watersheds of North Carolina1

Boggs, Johnny, Ge Sun, David Jones, and Steven G. McNulty, 2012. Effect of Soils on Water Quantity and Quality in Piedmont Forested Headwater Watersheds of North Carolina. Journal of the American Water Resources Association (JAWRA) 1‐19. DOI: 10.1111/jawr.12001 Abstract: Water quantity and quality data were compared from six headwater watersheds on two distinct soil formations, Carolina Slate Belt (CSB) and Triassic Basins (TB). CSB soils are generally thicker, less erodible, and contain less clay content than soils found in TB. TB generated significantly more discharge/precipitation ratio than CSB (0.33 vs. 0.24) in the 2009 dormant season. In the 2009 growing season, TB generated significantly less discharge/precipitation ratio than CSB (0.02 vs. 0.07). Over the entire monitoring period, differences in discharge/precipitation ratios between CSB and TB were not significantly different (0.17 vs. 0.20, respectively). Storm‐flow rates were significantly higher in TB than CSB in both dormant and growing season. Benthic macroinvertebrate biotic index scores were excellent for all streams. Nutrient concentrations and exports in CSB and TB were within background levels for forests. Low‐stream nitrate and ammonium concentrations and exports suggested that both CSB and TB were nitrogen limited. Soils appear to have had a significant influence on seasonal and storm‐flow generation, but not on long‐term total water yield and water quality under forested conditions. This study indicated that watersheds on TB soils might be more prone to storm‐flow generation than on CSB soils when converted from forest to urban. Future urban growth in the area should consider differences in baseline hydrology and effects of landuse change on water quantity and quality.     

Characterization of Drought in the South Atlantic,United States

Drought has been less extensively characterized in the humid South Atlantic compared to the arid western United States. Our objective was to characterize drought in the South Atlantic and to understand whether drought has become more severe in this region over time. Here we used monthly streamflow to characterize hydrological drought. Hydrological drought occurred when streamflow fell below the 20th percentile over three consecutive months and terminated once streamflow remained above the 20th percentile for three consecutive months. We characterized the frequency, duration, magnitude, and severity of events using the above definition. Significant changes in drought characteristics were tested with Mann‐Kendall over three periods: 1930‐2010, 1930‐1969, and 1970‐2010. We show that 71% of drought events were shorter than six months, while 7% were multiyear events. There was little evidence of trends in drought characteristics to support the claim of drought becoming more severe in the South Atlantic over the 20th Century. The one exception was a significant increase in the joint probability of nearby basins being simultaneously in drought conditions in the southern portion of the study area from 1970 to 2010. While drought characteristics have changed little through time, decreasing average streamflow in non drought periods coupled with increasing water demand provide the context within which recent multiyear drought events have produced significant stress on existing water infrastructure.     

A Non-confrontational Approach to Socially Responsible Air Pollution Control: The electoral experience of Kitakyushu

Social scientists have described Japan's urban anti-pollution protests in the 1960s as a national phenomenon. However, in Kitakyushu, Japan's most polluted industrial city at that time, no distinct citizens' movement developed. Because local politics and economics were so dominated by large industry, its citizens were reluctant to directly challenge these industries. Instead, local women's groups studied local pollution problems and presented their general findings to the public. These activities raised public awareness and resulted in increased support for local leftist politicians because leftist administrations had succeeded in cutting pollution in their cities. Kitakyushu's conservative mayor and local industry both became concerned that leftists would win the next local elections if pollution was not reduced. Thus the municipal government utilised scientific pollution data and prepared individualised pollution reduction recommendations in sulphur oxide pollution control agreements, which were accepted and complied with by all local industries. The result was a significant reduction in air pollution without the need for active intervention from Kitakyushu's citizenry. Cientificos sociales han descrito las protestas anti-polución urbana de Japon en los años 60 como un fenómeno nacional. Sinembargo, en Kitakyushu, ciudad industrial japonesa más polucionada en ese tiempo, no se desarrollóningún movimiento ciudadano evidente. Debido a que las políticas locales y económicas eran dominadas por la gran industria, sus ciudadanos no estaban dispuestos a retar directamente estas industrias. En lugar de eso, grupos locales de mujeres estudiaron problemas locales de polución y presentaron sus resultados al público. Estas actividades despertaron conciencia pública y resultaron en el incremento del apoyo para políticos izquierdistas locales debido a que las administraciones izquierdistas habían triunfado en la reducción de la polución en sus ciudades. El alcalde conservador y la industria local de Kitakyushu empezaron a preocuparse que los izquierdistas ganarían las próximas elecciones locales si la polución no era reducida. Asíque, el Gobierno Municipal utilizó información científica sobre polución y preparó recomendaciones de reducción de polución individualizada en acuerdos de control de polución en oxído sulfurico, los cuales fueron aceptados y obedecidos por todas las industrias locales. El resultado fue una significativa reducción en la polución del aire sin la necesidad de la intervención activa de parte de la ciudadania de Kitakyushu.