Vulnerability Assessment of Sea Level Rise Over Port Said Governorate, Egypt

An assessment of the impact of sea level rise on the city of Port Said, Egypt has been carried out using remote sensing and GIS techniques. Bruun's is used to estimate horizontal retreat, due to three scenarios of sea level rise, taking into account local subsidence rates. Overlaying horizontal retreat on land use obtained by remote sensing enabled us to estimate possible losses and socio-economic impacts. Results indicate serious physical and socio-economic impacts. It is suggested that protection measures must be carried out with emphasis on building breakwaters along the most vulnerable shoreline area.     

Impacts of vineyard area dynamics on soil erosion in a Mediterranean catchment (1950-2011)

The Mediterranean basin has undergone widespread land cover change. Urbanization of coastal areas, land abandonment of steeper slopes, and agricultural intensification in alluvial plains are recurrent themes. The objective of this study was to examine how vineyard land cover changes have affected agricultural soil erosion in a 50 year period (1950–2011). The study area covers a 235 km² catchment located near the Gulf of St Tropez. Aerial photographs were used to map land cover in 1950, 1982, 2003 and 2011, and the RUSLE soil erosion model was run to estimate soil erosion.

Between 1950 and 2011, vineyard went from about 2,426 ha to 1,561 ha. Mean soil erosion increased as vineyard slopes became steeper (11.8 T ha^?1, 13.2 T ha^?1, 14.4 T ha^?1 and 13.5 T ha^?1 for 1950, 1982, 2003 and 2011). Total erosion decreased after 1982: 28,621 T y^?1 in 1950, 29,030 T y^?1 in 1982, 22,848 T y^?1 in 2003, and 21,074 T y^?1 in 2011. Total soil loss in 2011 is about 75% of values in 1950–1982, so impacts on water pollution and channel dredging have evolved positively over time.     

Assessment of pollution of potentially harmful elements in soils surrounding a municipal solid waste incinerator,China

We assessed the contamination levels of Mn, Zn, Cr, Cu, Ni, Pb, As and Hg and the risks posed by these potentially harmful elements in top-soils around a municipal solid waste incinerator (MSWI).We collected 20 soil samples, with an average pH of 8.1, and another fly ash sample emitted from the MSWI to investigate the concentrations of these elements in soils. We determined the concentrations of these elements by inductively coupled plasma–optical emission spectrometer (ICP-OES), except for Hg, which we measured by AF-610B atomic fluorescence spectrometer (AFS). We assessed the risks of these elements through the use of geoaccumulation index (I _geo), potential ecological risk index (RI), hazard quotient (HQ _i ) and cancer risk (Risk _i ). The results showed that concentrations of potentially harmful elements in soil were influenced by the wind direction, and the concentrations of most elements were higher in the area northwest of the MSWI, compared with the area southeast of the incinerator, with the exception of As; these results were in accordance with those results acquired from our contour maps. According to the I _geo values, some soil samples were clearly polluted by Hg emissions. However, the health risk assessment indicated that the concentrations of Hg and other elements in soil did not pose non-carcinogenic risks to the local populations. This was also the case for the carcinogenic risks posed by As, Cr, and Ni. The carcinogenic risk posed by As was higher, in the range 6.49 × 10^–6–9.58 × 10^–6, but this was still considered to be an acceptable level of risk.

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川中丘陵区紫色土坡耕地土壤侵蚀特征

利用137Cs示踪方法与耕作侵蚀模型评价了川中丘陵区紫色土坡耕地土壤侵蚀速率,并通过比较分析方法探讨了2种典型坡耕地-短陡坡与缓长坡耕地-土壤侵蚀特征差异。结果表明,短陡坡耕地土壤侵蚀速率高达52.6 t.hm-2.a-1,是缓长坡耕地土壤侵蚀速率（26.7 t.hm-2.a-1）的2倍。耕作侵蚀是短陡坡耕地的主要侵蚀过程,它整体性搬运土壤,其对土壤总侵蚀的贡献高达74%。水蚀是缓长坡耕地的主要侵蚀过程,其分选性搬运土壤,对土壤总侵蚀的贡献为55%。短陡坡耕地与缓长坡耕地土壤侵蚀速率均沿着向下坡方向逐渐降低,但短陡坡耕地土壤侵蚀速率下降梯度明显高于缓长坡耕地。耕作侵蚀导致两种坡耕地的坡顶土壤损失最为严重。因此,川中丘陵区的耕作侵蚀风险应该引起重视。     

土壤侵蚀环境演变与全球变化及防灾减灾的机制

以土壤侵蚀学和环境学的交叉为基础,讨论了土壤侵蚀环境学的内涵、土壤侵蚀环境演变及其调控、全球变化及防灾减灾的机制。为揭示土壤侵蚀的实质及制定土壤侵蚀的防治对策提供了新的思想。     

CHANNEL MORPHOLOGY EVOLUTION AND OVERBANK FLOW IN THE GEORGIA PIEDMONT1

ABSTRACT: Historic changes in stream channel morphology were investigated in the Georgia Piedmont to better understand the hydrologic processes and functioning of the region's riverine systems. USGS gaging station data and channel geomorphology data were collected from thirty study sites in the Upper Oconee River Basin for flood frequency analysis. Historic and modern (i.e., present-day) channel capacity discharge (i.e., overbank flow) was calculated using Manning's equation and historic channel cross-section records. The recurrence interval for overbank flow was estimated for each site from flood frequency data. Results indicate that channel expansion has occurred throughout the basin, especially in upper reaches. Recurrence intervals for modern overbank events were variable and generally high ranging from < 2 to > 500 years for first to third order streams. They were less variable and lower for fourth and fifth order streams, ranging from < 2 to 3 years. Potential depositional thresholds were identified that exemplify the complex response of sediment distribution patterns throughout the basin. Results indicate overbank flows occur less frequently now than they once did due to historic accelerated sedimentation and subsequent channel expansion. One application of these findings is that these basin processes are likely applicable across the region and may impact the hydrologic functioning of associated Piedmont riverine wetlands that depend on flooding regimes.     

示踪法在土壤侵蚀研究中的应用及存在的问题

鉴于用示踪法研究土壤侵蚀已成为国际社会普遍关注的热点问题,结合国内外最新研究进展,主要介绍了放射性核素示踪（137Cs,210Pbex,7Be,复合核素）、稀土元素（REE）示踪、磁性示踪等3类主要示踪法在土壤侵蚀研究中的应用概况及进展,结合示踪法在土壤侵蚀研究中的特点,分析了示踪法在土壤侵蚀研究中存在的问题以及在今后的发展方向和应用前景。     

长江上游水资源开发利用研究——以重庆市为例

介绍了长江上游地区水资源开发利用情况，并以重庆市为例，从重庆市水资源实际情况和开发利用现状出发，针对水资源在开发利用中存在的问题，提出了相应的对策措施，其中涵盖了三峡库区的水生态环境保护问题，以期为重庆市水资源规划和管理提供参考。     

基于遥感方法的小流域土壤侵蚀研究

探讨了利用遥感技术进行小流域土壤侵蚀计算的方法。应用通用土壤侵蚀方程,借助RS和GIS技术,对模型各参数因子进行精确计算,实现了基于栅格信息的土壤侵蚀计算模型。选择黄河皇甫川五分地沟小流域作为典型研究区,讨论了适宜植被盖度对减小土壤侵蚀模数的影响。