Land reclamation is gradually posing negative impact on man due to unplanned urbanization. A study was carried out on impact of land reclamation through sand mining of coastal communities in Ikate and Ilubirin in Lago...Land reclamation is gradually posing negative impact on man due to unplanned urbanization. A study was carried out on impact of land reclamation through sand mining of coastal communities in Ikate and Ilubirin in Lagos, Nigeria. Ten waters (8 surface and 2 groundwater sources), 10 soil samples and air were collected and taken for analysis. Results of water revealed concentrations lower than WHO (2017) and SON (2007) standards. Soil/sediment with average crustal value revealed Pb and Cd above standard values, which is attributed to anthropogenic influence on soils. Quality of air in the study was mainly particulate matter arising from the sea and reclaimed land in the surroundings of the environment with the highest Total Suspended Particulate of 0.8 mg/m3 in sulfur dioxide. This explains corrosion found on the roofs of the communities. Therefore, in the development planning adequate precautions should be put in place to avert environmental degradation.展开更多
The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses o...The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP： 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area.展开更多
This paper presents the results of the investigations, driven by different techniques, including environmental tracers and geophysical methods, in the aim of better understand the causes of the current salt-water intr...This paper presents the results of the investigations, driven by different techniques, including environmental tracers and geophysical methods, in the aim of better understand the causes of the current salt-water intrusion in the Pontina Plain, in the south of the Lazio Region (Italy). In the last 50 years many investigation campaigns have been carried out to evaluate the evolution of salt-water intrusion. This is an area with a strong man-made residential and tourist impact and, in the some cases, it is characterized by intensive agricultural practices. Therefore, it can be affected not only by salt-water intrusion, but by the salinization of its groundwater also due to other factors. All these factors have led the Pontina Plain to a groundwater situation which makes the groundwater resource management and the planning of their future exploitation very difficult.展开更多
In this study, some environmental factors were investigated to assess the potential effects on the dynamics of a dinoflagellate red tide caused by Gymnodinium catenatum in Shenhu Bay coastal waters in June, 2017. The ...In this study, some environmental factors were investigated to assess the potential effects on the dynamics of a dinoflagellate red tide caused by Gymnodinium catenatum in Shenhu Bay coastal waters in June, 2017. The highest cell density of G. catenatum was 1.0×10 6 cells/L, so it was known as the predominant species of the red tide discovered in Fujian coastal waters for the first time. Continuous rainfall process brought many land-based pollutants into the coastal waters, providing abundant nutrients for plankton growth. Then the continuous sunny and hot weather, high temperature, high salinity and south wind conditions accelerated the formation and occurrence of the red tide. During the red tide, DO, pH and COD increased remarkably and had significant positive correlations with the cell density of the red tide organisms. The contents of various nutrients decreased obviously, and eutrophication index E became low before and after the red tide, indicating the oligotrophic status of Shenhu Bay coastal waters. It is also found that DIP was one of the determinant environmental factors that induced the red tide. The N/P ratio of water in the declining phase of the red tide was close to the Redfield ratio. As for DIN, NH + 4-N and NO - 3-N were the two main species of inorganic nitrogen needed for this red tide dinoflagellate. The study indicates the relationship between the occurrence of the red tide and environmental conditions, providing essential reference for monitoring and forecasting research of red tide in marine environment and ecosystem management.展开更多
以天津市近岸海域为例,通过对地统计学的研究和地理信息系统(GIS,geographic information system)软件的应用,提出了一种完全基于环境监测数据的计算近海水环境容量的新方法．首先对COD监测数据进行地统计学分析,确定研究海域有机物分...以天津市近岸海域为例,通过对地统计学的研究和地理信息系统(GIS,geographic information system)软件的应用,提出了一种完全基于环境监测数据的计算近海水环境容量的新方法．首先对COD监测数据进行地统计学分析,确定研究海域有机物分布的空间结构特征;其后以此为基础,采用普通克里格法对整个天津市近海的有机物浓度进行空间插值;最后,借助GIS软件的地图代数运算功能,依据质量守恒原理,建立近海水环境容量的计算方法,估算出最不利状态下天津市近海的水环境容量．通过应用表明,本方法避免了复杂的模型计算,具有原理简单、实用性强等特点,适合在近海环境管理中应用．展开更多
文摘Land reclamation is gradually posing negative impact on man due to unplanned urbanization. A study was carried out on impact of land reclamation through sand mining of coastal communities in Ikate and Ilubirin in Lagos, Nigeria. Ten waters (8 surface and 2 groundwater sources), 10 soil samples and air were collected and taken for analysis. Results of water revealed concentrations lower than WHO (2017) and SON (2007) standards. Soil/sediment with average crustal value revealed Pb and Cd above standard values, which is attributed to anthropogenic influence on soils. Quality of air in the study was mainly particulate matter arising from the sea and reclaimed land in the surroundings of the environment with the highest Total Suspended Particulate of 0.8 mg/m3 in sulfur dioxide. This explains corrosion found on the roofs of the communities. Therefore, in the development planning adequate precautions should be put in place to avert environmental degradation.
基金National Natural Science Foundation of China, No.40471122
文摘The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP： 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area.
文摘This paper presents the results of the investigations, driven by different techniques, including environmental tracers and geophysical methods, in the aim of better understand the causes of the current salt-water intrusion in the Pontina Plain, in the south of the Lazio Region (Italy). In the last 50 years many investigation campaigns have been carried out to evaluate the evolution of salt-water intrusion. This is an area with a strong man-made residential and tourist impact and, in the some cases, it is characterized by intensive agricultural practices. Therefore, it can be affected not only by salt-water intrusion, but by the salinization of its groundwater also due to other factors. All these factors have led the Pontina Plain to a groundwater situation which makes the groundwater resource management and the planning of their future exploitation very difficult.
基金Supported by Key Laboratory of Integrated Marine Monitoring Technology and Applied Technologies for Harmful Algal Blooms,State Oceanic Administration(MATHAB201802)
文摘In this study, some environmental factors were investigated to assess the potential effects on the dynamics of a dinoflagellate red tide caused by Gymnodinium catenatum in Shenhu Bay coastal waters in June, 2017. The highest cell density of G. catenatum was 1.0×10 6 cells/L, so it was known as the predominant species of the red tide discovered in Fujian coastal waters for the first time. Continuous rainfall process brought many land-based pollutants into the coastal waters, providing abundant nutrients for plankton growth. Then the continuous sunny and hot weather, high temperature, high salinity and south wind conditions accelerated the formation and occurrence of the red tide. During the red tide, DO, pH and COD increased remarkably and had significant positive correlations with the cell density of the red tide organisms. The contents of various nutrients decreased obviously, and eutrophication index E became low before and after the red tide, indicating the oligotrophic status of Shenhu Bay coastal waters. It is also found that DIP was one of the determinant environmental factors that induced the red tide. The N/P ratio of water in the declining phase of the red tide was close to the Redfield ratio. As for DIN, NH + 4-N and NO - 3-N were the two main species of inorganic nitrogen needed for this red tide dinoflagellate. The study indicates the relationship between the occurrence of the red tide and environmental conditions, providing essential reference for monitoring and forecasting research of red tide in marine environment and ecosystem management.
文摘以天津市近岸海域为例,通过对地统计学的研究和地理信息系统(GIS,geographic information system)软件的应用,提出了一种完全基于环境监测数据的计算近海水环境容量的新方法．首先对COD监测数据进行地统计学分析,确定研究海域有机物分布的空间结构特征;其后以此为基础,采用普通克里格法对整个天津市近海的有机物浓度进行空间插值;最后,借助GIS软件的地图代数运算功能,依据质量守恒原理,建立近海水环境容量的计算方法,估算出最不利状态下天津市近海的水环境容量．通过应用表明,本方法避免了复杂的模型计算,具有原理简单、实用性强等特点,适合在近海环境管理中应用．
