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China’s Largest Carrier Rocket Long March-5 Makes New Flight 预览
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《今日中国:英文版》 2020年第2期12-13,共2页
China launched the third Long March-5,the largest carrier rocket of the country,from Wenchang Space Launch Center in south China’s Hainan Province on the evening of December 27,2019.The rocket,coded as Long March-5 Y... China launched the third Long March-5,the largest carrier rocket of the country,from Wenchang Space Launch Center in south China’s Hainan Province on the evening of December 27,2019.The rocket,coded as Long March-5 Y3,blasted off from the coastal launch center at 8:45 p.m.(Beijing time),carrying the Shijian-20 technological experiment satellite weighing over eight tonnes,the heaviest and most advanced communications satellite of the country. 展开更多
关键词 ROCKET COASTAL ROCKET
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临海码头钢结构的防腐施工技术 预览
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作者 胡辉 《建筑施工》 2020年第3期431-434,共4页
某临海码头项目的钢结构构件一直处于浪溅、潮气及水的冲击和侵蚀等腐蚀环境之中。为此,通过对位于不同部位的钢结构的防腐技术及施工难点进行分析,并结合实际施工经验,找出了有效的施工方法。经实践,项目的完工效果符合业主要求,为类... 某临海码头项目的钢结构构件一直处于浪溅、潮气及水的冲击和侵蚀等腐蚀环境之中。为此,通过对位于不同部位的钢结构的防腐技术及施工难点进行分析,并结合实际施工经验,找出了有效的施工方法。经实践,项目的完工效果符合业主要求,为类似项目的实施积累了经验。 展开更多
关键词 临海 港建钢结构 防腐施工 喷涂设备 免翻身涂装
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Flexible feeding patterns of copepod Centropages tenuiremis in fluctuating conditions: a possible survival strategy to cope with disturbance 预览
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作者 Cuilian Xu Simin Hu +4 位作者 Zhiling Guo Tao Li Hui Huang Leo Lai Chan Sheng Liu 《海洋学报:英文版》 SCIE CAS CSCD 2020年第2期59-68,共10页
Centropages tenuiremis is a species with a wide distribution range in disturbed coastal waters.However,due to a lack of dietary information,it remains unclear as to how they maintain such dominance in fluctuating cond... Centropages tenuiremis is a species with a wide distribution range in disturbed coastal waters.However,due to a lack of dietary information,it remains unclear as to how they maintain such dominance in fluctuating conditions.In this study,C.tenuiremis was collected from the Daya Bay Nuclear Power Plant both in inlet and outfall regions at 06:00,12:00 and 18:00 on April 27,2011 and their in situ diet was analyzed using a PCR protocol targeting 18S ribosomal genes.Thirty-four species of prey organisms were identified totally,including Dinophyta,Baciliariophyta,Viridiplantae,Rhizaria,Apicomplexa,Chordata,Mollusca,Arthropoda and Fungi,indicating an obvious omnivorous feeding habit of C.tenuiremis.Centropages tenuiremis obviously exhibited spatial and temporal variations in diet composition.More plant prey(land plants and phytoplankton)were consumed in the morning(~50%),while more animal prey(metazoans and protozoans)were ingested at midday and night(60%–70%).Furthermore,a more diverse diet was detected in the outfall region(10–11 taxa),where the temperatures were relatively higher and more fluctuating,than in the control region(5–10 taxa).This finding indicated that C.tenuiremis could potentially expand its food spectrum under stressful condition.Specifically,C.tenuiremis exhibited phytoplankton preference(58.62%–67.64%)in the outfall region with a lower omnivory index(0.27–0.35)than in the control region(0.51–0.95).However,phytoplankton density was lower than that in the control region,suggesting a possible herbivorous tendency of C.tenuiremis under elevated temperatures to balance the energy acquirement and feeding effort.The flexible food choices of C.tenuiremis observed here could effectively buffer environmental fluctuations and might be an important survival strategy in coastal ecosystems. 展开更多
关键词 Centropages FEEDING response strategy COASTAL ECOSYSTEM DAYA BAY
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Geographical Variation and Influencing Factors of Spartina alterniflora Expansion Rate in Coastal China 预览
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作者 ZHANG Danhua HU Yuanman +2 位作者 LIU Miao CHANG Yu SUN Lishuang 《中国地理科学:英文版》 SCIE CSCD 2020年第1期127-141,共15页
Biological invasion poses a huge threat to ecological security.Spartina alterniflora was introduced into China in 1979,and its arrival corresponded with negative effects on native ecosystems.To explore geographical va... Biological invasion poses a huge threat to ecological security.Spartina alterniflora was introduced into China in 1979,and its arrival corresponded with negative effects on native ecosystems.To explore geographical variation of its expansion rate in coastal China,we selected 43 S.alterniflora sites from Tianjin Coastal New Area to Beihai.The area expansion rate,expansion rate paralleling and vertical to the shoreline were analysed based on Landsat images and field survey in 2015.Simple Ocean Data Assimilation(SODA)and climate data were collected to statistically analyse the influential factors of expansion rate.Results showed that significant difference of S.alterniflora area expansion rate among different latitude zones(P<0.01),increasing from 6.08%at southern(21°N–23°N)to 19.87% in Bohai Bay(37°N–39°N)along latitude gradient.There was a significant difference in expansion rate vertical to shoreline in different latitude zones(P<0.01)with the largest occurring in Bohai Bay(256m/yr,37°N–39°N),and showed an decreasing tendency gradually from north to south.No significant difference and latitudinal clines in expansion rate paralleling to shoreline were observed.Expansion rate had significant negative correlation with mean seawater temperature,the lowest seawater temperature,current zonal velocity and meridional velocity and presented a reducing trend as these biotic factors increased;however,they were not significantly correlated with the highest seawater temperature and mean seawater salinity.We identified significant correlations between expansion rate and annual mean temperature,the lowest temperature in January and annual precipitation,but there was little correlation with annual diurnal difference in temperature and the highest temperature in July.The rapid expansion rate in high-latitude China demonstrated a higher risk of potential invasion in the north;dynamic monitoring and control management should be established as soon as possible. 展开更多
关键词 GEOGRAPHICAL variation biological INVASION SPARTINA alterniflora expansion rate COASTAL WETLANDS China
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水-沙变化趋势影响世界大河发展方向
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作者 胡春宏 《科学通报:英文版》 SCIE EI CSCD 2020年第1期4-6,M0003共4页
As the primary fluxes transported by rivers,water and sediment play a crucial role in the evolution of riverine-estuarinecoastal topography and the establishment of ecological systems[1].Under the impact of climate ch... As the primary fluxes transported by rivers,water and sediment play a crucial role in the evolution of riverine-estuarinecoastal topography and the establishment of ecological systems[1].Under the impact of climate change and human activities,river discharge suffered significant changes worldwide[2,3]in the past decades.These changes have resulted in a variety of consequences[1].Meanwhile,global interests in water issues have been extended from water resources to water-related disasters,and ecological and environmental problems[4-7]. 展开更多
关键词 TOPOGRAPHY COASTAL consequences
Application of the Static Headland-Bay Beach Concept to a Sandy Beach: A New Elliptical Model 预览
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作者 LI Bing ZHUANG Zhenye +1 位作者 CAO Lihua DU Fengchao 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2020年第1期81-89,共9页
The headland-bay beach is one of the most common coastal types in the world.Its morphology reflects the changes that occurred during long-term evolution of the sandy coast.Several headland-bay beach models have been p... The headland-bay beach is one of the most common coastal types in the world.Its morphology reflects the changes that occurred during long-term evolution of the sandy coast.Several headland-bay beach models have been proposed to simulate the coastline’s configuration in equilibrium.In this paper,a new elliptical model is proposed,described,and applied.On the east coast of Laizhou Bay in Shandong Province from Longkou Port to Diaolongzui,four typical headland-bay beaches have developed,and four headland-bay beach models are used in this paper to simulate the morphology of these beaches to assess the applicability of each model.The simulation results of the elliptical model verify that it is applicable to the study area.In addition,the elliptical model is easy to use.Through simulation and field investigations,we concluded that most of the coastal segments in this area will remain in an erosion state,and the human activity has a significant impact on the shoreline’s evolution. 展开更多
关键词 static headland-bay beach concept elliptical model sandy beach coastal erosion east coast of Laizhou Bay
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RESPONSIVE TRANSFORMATION 预览
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作者 Zuo Lin 《中国东盟报道(英文)》 2020年第2期68-69,共2页
Due to the sudden outbreak of the novel coronavirus,Sheng Lei,a garment factory owner from the coastal Jiangsu Province in east China,made more than a few major changes over the Spring Festival holiday.He cancelled a ... Due to the sudden outbreak of the novel coronavirus,Sheng Lei,a garment factory owner from the coastal Jiangsu Province in east China,made more than a few major changes over the Spring Festival holiday.He cancelled a family trip to Xi’an,a popular tourist destination in western China’s Shaanxi Province.More boldly,the enterprising soul decided to shift his well-established business operating since 1997 to a new sector:face masks. 展开更多
关键词 COASTAL DESTINATION Jiangsu
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Numerical investigation on tsunami wave mitigation on forest sloping beach 预览
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作者 Mingliang Zhang Yongpeng Ji +2 位作者 Yini Wang Hongxing Zhang Tianping Xu 《海洋学报:英文版》 SCIE CAS CSCD 2020年第1期130-140,共11页
An explicit one-dimensional model based on the shallow water equations(SWEs) was established in this work to simulate tsunami wave propagation on a vegetated beach. This model adopted the finite-volume method(FVM)for ... An explicit one-dimensional model based on the shallow water equations(SWEs) was established in this work to simulate tsunami wave propagation on a vegetated beach. This model adopted the finite-volume method(FVM)for maintaining the mass balance of these equations. The resistance force caused by vegetation was taken into account as a source term in the momentum equation. The Harten–Lax–van Leer(HLL) approximate Riemann solver was applied to evaluate the interface fluxes for tracing the wet/dry transition boundary. This proposed model was used to simulate solitary wave run-up and long-periodic wave propagation on a sloping beach. The calibration process suitably compared the calculated results with the measured data. The tsunami waves were also simulated to discuss the water depth, tsunami force, as well as the current speed in absence of and in presence of forest domain. The results indicated that forest growth at the beach reduced wave energy loss caused by tsunamis. A series of sensitivity analyses were conducted with respect to variable parameters(such as vegetation densities, wave heights, wave periods, bed resistance, and beach slopes) to identify important influences on mitigating tsunami damage on coastal forest beach. 展开更多
关键词 SHALLOW water equations HLL scheme TSUNAMI waves COASTAL vegetation WAVE propagation
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An Ocean of Opportunity:Seaweed farming has become a lucrative operation in coastal regions of East Africa
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作者 Geoffrey Kamadi 《中国与非洲:英文版》 2020年第2期30-31,共2页
A thriving trade in seaweed is fast taking root on the seabed of the East African coast,effectively becom ing a commercial venture of choice for many communities living along the Indian Ocean.Despite the trade being d... A thriving trade in seaweed is fast taking root on the seabed of the East African coast,effectively becom ing a commercial venture of choice for many communities living along the Indian Ocean.Despite the trade being driven by demand from China,Ireland,South Korea,Japan and Malaysia,the plant has also found a market locally. 展开更多
关键词 East COASTAL INDIAN
Wintertime Guangdong coastal currents successfully captured by cheap GPS drifters 预览
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作者 Hongyang Lin Zhenyu Sun +2 位作者 Zhaozhang Chen Jia Zhu Jianyu Hu 《海洋学报:英文版》 SCIE CAS CSCD 2020年第1期166-170,共5页
This study introduces a type of self-developed, GPS-based, simple and cheap Surface Current Experiment(SUCE)drifters designated for observing surface coastal currents. By examining trajectories of six drifters deploye... This study introduces a type of self-developed, GPS-based, simple and cheap Surface Current Experiment(SUCE)drifters designated for observing surface coastal currents. By examining trajectories of six drifters deployed in the Daya Bay and the drifter-derived velocities, we conclude that such drifters are generally capable of capturing the characteristics of wintertime surface coastal currents along the Guangdong coast. 展开更多
关键词 GPS DRIFTER TRAJECTORY COASTAL current
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近海环境中抗生素分析样品前处理技术的研究进展 预览
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作者 吕敏 陈令新 《色谱》 CAS CSCD 北大核心 2020年第1期95-103,共9页
抗生素在人和动物疾病防治方面的广泛及大量使用造成其源源不断地进入到环境中,并最终通过各种途径进入到近海环境中。由于抗生素可在水生生物体内蓄积,特别是其可促进细菌耐药性的产生与传播,已经威胁到生态和人类健康。抗生素种类复... 抗生素在人和动物疾病防治方面的广泛及大量使用造成其源源不断地进入到环境中,并最终通过各种途径进入到近海环境中。由于抗生素可在水生生物体内蓄积,特别是其可促进细菌耐药性的产生与传播,已经威胁到生态和人类健康。抗生素种类复杂、性质各异,且在环境中存在浓度低,因此,发展各种基质中抗生素分析的前处理方法至关重要。该文综述了近十几年来近海水体、沉积物和生物体中抗生素的前处理方法,主要包括固相萃取、固液萃取、基质固相分散萃取和QuEChERS等几种常用前处理技术,并对方法中可能影响萃取和净化效果的各种因素进行了分析,最后对各种方法的优缺点和发展进行了总结和展望。 展开更多
关键词 抗生素 近海 前处理技术 综述
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Impacts of Coastal Reclamation on Natural Wetlands in Large River Deltas in China 预览
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作者 MA Tiantian LI Xiaowen +1 位作者 BAI Junhong CUI Baoshan 《中国地理科学:英文版》 SCIE CSCD 2019年第4期640-651,共12页
Little information is available on the impacts of coastal reclamation on wetland loss in large-river deltas at a regional scale.Using remote sensing data of coastal wetland and reclamation in four deltas in China from... Little information is available on the impacts of coastal reclamation on wetland loss in large-river deltas at a regional scale.Using remote sensing data of coastal wetland and reclamation in four deltas in China from 1978 to 2014, we tracked their continuous area changes in four periods: 1978–1990, 1990–2000, 2000–2008, and 2008–2014. The areal relation between wetland loss and reclamation was quantified and used to identify coastal reclamation mode intensity coupled with another three indicators: reclamation rate,accretion rate and land-use intensity of coastal reclamation. The results showed that coastal reclamation driven by economic development reduced, or even reverse the original growth of delta which was determined by the offset between wetland acceleration rate and wetland loss rate. Generally, the area of reclamation showed a positive linear correlation with the area of wetland loss. The findings imply that human activities should control reclamation rate and intensity to alleviate total wetland loss and maintain wetland ’net gain’.Inappropriate coastal reclamation modes can magnify total wetland loss;therefore, coastal reclamation with a slow increment rate and low impervious surface percent is of great importance for sustainable development in future coastal management. 展开更多
关键词 COASTAL RECLAMATION WETLAND loss COASTAL RECLAMATION mode multi-case comparison large river DELTA COASTAL management
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Photodegradation of 2-(2-hydroxy-5-methylphenyl) benzotriazole (UV-P) in coastal seawaters: Important role of DOM
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作者 Xi Chen Jieqiong Wang +3 位作者 Jingwen Chen Chengzhi Zhou Feifei Cui Guoxin Sun 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第11期129-137,共9页
Benzotriazole UV stabilizers (BT-UVs) have attracted concems due to their ubiquitous occurrence in the aquatic environment,and their bioaccumulative and toxic properties.However,little is known about their aquatic env... Benzotriazole UV stabilizers (BT-UVs) have attracted concems due to their ubiquitous occurrence in the aquatic environment,and their bioaccumulative and toxic properties.However,little is known about their aquatic environmental degradation behavior.In this study,photodegradation of a representative of BT-UVs,2-(2-hydroxy-5-methylphenyl) benzotriazole (UV-P),was investigated under simulated sunlight irradiation.Results show that UV-P photodegrades slower under neutral conditions (neutral form) than under acidic or alkaline conditions (cationic and anionic forms).Indirect photodegradation is a dominant elimination pathway of UV-P in coastal seawaters.Dissolved organic matter (DOM) from seawaters accelerate the photodegradation rates mainly through excited triplet DOM (3DOM*),and the roles of singlet oxygen and hydroxyl radical are negligible in the matrixes.DOM from seawaters impacted by mariculture exhibits higher steady-state concentration of 3DOM*([3DOM*]) relative to those from pristine seawaters,leading to higher photosensitizing effects on the photodegradation.Halide ions inhibit the DOM-sensitized photodegradation of UV-P by decreasing [3DOM*].Photodegradation half-lives of UV-P are estimated to range from 24.38 to 49.66 hr in field water bodies of the Yellow River estuary.These results are of importance for assessing environmental fate and risk UV-P in coastal water bodies. 展开更多
关键词 BENZOTRIAZOLE UV STABILIZERS PHOTODEGRADATION Dissolved organic matter COASTAL seawaters
Analysis of the Mamaia Bay shoreline Retreat with Hard and Soft Protection Works 预览
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作者 Catalin Anton Carmen Gasparotti +1 位作者 Iulia Alina Anton Eugen Rusu 《海洋科学杂志(英文)》 2019年第1期7-17,共11页
Integrated Coastal Zone Management is a complex concept that involves various economic, social and environmental factors. There are often conflicting approaches to these factors. Furthermore, when it is decided to imp... Integrated Coastal Zone Management is a complex concept that involves various economic, social and environmental factors. There are often conflicting approaches to these factors. Furthermore, when it is decided to implement structural works in the coastal area, it must be taken into account the particularity of the area, the way in which it is developed and the type of work to be done. The Gulf of Mamaia in the Romanian Black Sea coast is the target of structural changes through the implementation of an extensive coastal rehabilitation program. The works made are of “hard” type and aim to change the shore line configuration. From this perspective, the target of the present paper is to make an analysis between the type of work that is being carried out and another kind of "soft" work aiming especially to favor the ecological reconstruction of the area and the approach of an environmentally friendly concept. Thus, we propose to analyze the two types of works with a view to apply the Bruun rule in order to mitigate the effect of the increase of the sea level and to prevent the shoreline retreat. 展开更多
关键词 COASTAL zone management Romanian COAST Mamaia BAY Black Sea SHORELINE HARD and soft WORKS
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Hydrological and economic feasibility of mitigating a stressed coastal aquifer using managed aquifer recharge: a case study of Jamma aquifer, Oman 预览
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作者 Mustafa EL-RAWY Ali AL-MAKTOUMI +2 位作者 Slim ZEKRI Osman ABDALLA Rashid AL-ABRI 《干旱区科学:英文版》 SCIE CSCD 2019年第1期148-159,共12页
This study explored the hydrological and economic feasibility of managed aquifer recharge(MAR) using tertiary treated wastewater(TWW) to mitigate salinity in the coastal aquifer of Jamma, Oman. A steady-state groundwa... This study explored the hydrological and economic feasibility of managed aquifer recharge(MAR) using tertiary treated wastewater(TWW) to mitigate salinity in the coastal aquifer of Jamma, Oman. A steady-state groundwater flow and transport model, using MODFLOW software, was developed and calibrated. Different managerial scenarios were simulated and the results reveal that the Jamma aquifer will be further deteriorated in the next 20 a if it remains unmanaged. The groundwater table will decline further by more than 3 m on average;and the iso-concentration salinity line of 1500 mg/L will advance 2.7 km inland, which will severely affect the farming activities in the area. However, MAR using TWW when integrated with the management of groundwater abstraction(e.g., using modern irrigation systems to reduce the abstraction rate) becomes hydrologically feasible to augment the aquifer storage and control seawater intrusion, and hence improves the farming activities. The results indicate that:(1) injecting TWW in the vicinity of irrigation wells(Scenario A2);(2) investing in smart water meters and online control of pumping from the wells to reduce the abstraction rate by 25%(Scenario B);and(3) a combination of both(Scenario B2) are feasible scenarios with positive net present values. Recharge in upstream areas is found not economically feasible because of the very high investment cost of the installation of pipes to transport the TWW over a distance of 12.5 km. Because of securing funds are challenging, Scenario B would be the best option and the second-best option is Scenario A2. Scenario B2 has the lowest net benefit investment ratio and is very attractive because it entails integrated demand and supply management of groundwater. It is required to reduce pumping and to invest in injecting TWW to improve groundwater quality in the vicinity of irrigation wells and to form a hydrological barrier to control seawater intrusion in the long run. 展开更多
关键词 managed AQUIFER RECHARGE treated WASTEWATER SALINITY line COASTAL AQUIFER Oman
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Object-based classification of cloudy coastal areas using medium-resolution optical and SAR images for vulnerability assessment of marine disaster 预览
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作者 YANG Fengshuo YANG Xiaomei +3 位作者 WANG Zhihua LU Chen LI Zhi LIU Yueming 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第6期1955-1970,共16页
Efficient and accurate access to coastal land cover information is of great significance for marine disaster prevention and mitigation.Although the popular and common sensors of land resource satellites provide free a... Efficient and accurate access to coastal land cover information is of great significance for marine disaster prevention and mitigation.Although the popular and common sensors of land resource satellites provide free and valuable images to map the land cover,coastal areas often encounter significant cloud cover,especially in tropical areas,which makes the classification in those areas non-ideal.To solve this problem,we proposed a framework of combining medium-resolution optical images and synthetic aperture radar(SAR)data with the recently popular object-based image analysis(OBIA)method and used the Landsat Operational Land Imager(OLI)and Phased Array type L-band Synthetic Aperture Radar(PALSAR)images acquired in Singapore in 2017 as a case study.We designed experiments to confirm two critical factors of this framework:one is the segmentation scale that determines the average object size,and the other is the classification feature.Accuracy assessments of the land cover indicated that the optimal segmentation scale was between 40 and 80,and the features of the combination of OLI and SAR resulted in higher accuracy than any individual features,especially in areas with cloud cover.Based on the land cover generated by this framework,we assessed the vulnerability of the marine disasters of Singapore in 2008 and 2017 and found that the high-vulnerability areas mainly located in the southeast and increased by 118.97 km2 over the past decade.To clarify the disaster response plan for different geographical environments,we classified risk based on altitude and distance from shore.The newly increased high-vulnerability regions within 4 km offshore and below 30 m above sea level are at high risk;these regions may need to focus on strengthening disaster prevention construction.This study serves as a typical example of using remote sensing techniques for the vulnerability assessment of marine disasters,especially those in cloudy coastal areas. 展开更多
关键词 COASTAL area marine DISASTER VULNERABILITY assessment remote sensing land use/cover object-based image analysis(OBIA)
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沿海地区沥青混合料在低气温条件下施工可行性研究 预览
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作者 王永敏 侯跃敏 《工程建设与设计》 2019年第11期211-213,219共4页
随着公路建设的迅速发展,沥青路面低气温施工问题备受关注。低气温施工会对沥青路面的压实度、平整度等方面造成严重影响,从而加速沥青路面的损害。论文以沿海城市青岛为例,利用Pavecool软件在低气温条件参数下,对不同摊铺温度、环境气... 随着公路建设的迅速发展,沥青路面低气温施工问题备受关注。低气温施工会对沥青路面的压实度、平整度等方面造成严重影响,从而加速沥青路面的损害。论文以沿海城市青岛为例,利用Pavecool软件在低气温条件参数下,对不同摊铺温度、环境气温、风速及不同厚度的沥青混合料降温曲线进行数值计算,分析上述环境因素及混合料因素对沥青有效压实时间的影响,探索沥青混合料在低气温条件下施工的可行性方法。通过以上分析,得出对于同一种沥青混合料,适当降低临界温度、增加摊铺层厚度均可以有效延长压实时间。这一结果为沿海地区低气温条件下沥青混合料的施工新技术的发展提供了新的思路。 展开更多
关键词 沿海 低气温 沥青混合料 有效压实时间
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Spatial Distribution Characteristics of Nitrogen and Phosphorus in Sediments of Coastal Wetlands 预览
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作者 Huanqiang ZHENG Kun RONG 《亚洲农业研究:英文版》 2019年第1期42-46,共5页
Taking the typical coastal wetlands in the Yellow River Delta as the research object,(i)three parallel strips A1,A2 and A3 were set up along the vertical coastline in the newborn wetland at 60 km south of the Dongwenl... Taking the typical coastal wetlands in the Yellow River Delta as the research object,(i)three parallel strips A1,A2 and A3 were set up along the vertical coastline in the newborn wetland at 60 km south of the Dongwenliu Management Station in the Yellow River Delta Nature Reserve.(ii)Sample plots B(Phragmites communis area),C(Suaeda glauca area),and D(Tamarix chinensis area)were set up near the field ecological station of the coastal wetlands.Through collecting sediment samples and measuring nitrogen and phosphorus contents,the spatial distribution characteristics of nitrogen and phosphorus in sediments of coastal wetlands were studied.Following results were obtained.(i)The concentration of TN in the 0-20 cm surface sediments of the coastal wetlands in the Yellow River Delta was in the range of 130-695 mg/kg,the concentration of TP was in the range of 589-778 mg/kg,and the average content of TN and TP was 372.18 and 660.82 mg/kg respectively.(ii)From the remote coastal area of the Yellow River to the near coastal area,the horizontal distribution of TN in the sediments was different at each level,and the TN content in the surface sediments gradually decreased;the content of TP generally increased.(iii)At the profile level,the content of TN and TP generally showed a trend of decreasing gradually from the surface layer and tending to be stable,and the peak appeared at the outermost layer.(iv)In the sediments under different vegetation cover,TN was more evenly distributed on each profile,and the distribution of TP on each profile was different.TN showed the largest distribution in the 0-20 cm surface sediments in the T.chinensis area,while TP had the largest distribution in the 80-100 cm bottom sediments in the T.chinensis area. 展开更多
关键词 COASTAL WETLAND SEDIMENT NITROGEN PHOSPHORUS Spatial distribution
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需求导向下的滨海民宿庭院景观设计策略研究——以北戴河区为例 预览
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作者 于宝 王建梅 +1 位作者 杨雅婷 白冰 《黑龙江生态工程职业学院学报》 2019年第2期17-20,共4页
随着中国城市化进程的加快,城市居民对旅游度假需求的不断增加,旅游度假的发展也带动了民宿的兴起。民宿庭院景观是民宿设计中重要的组成部分,对民宿庭院景观设计的策略研究越来越成为研究者关注的课题。以秦皇岛市北戴河区民宿庭院景... 随着中国城市化进程的加快,城市居民对旅游度假需求的不断增加,旅游度假的发展也带动了民宿的兴起。民宿庭院景观是民宿设计中重要的组成部分,对民宿庭院景观设计的策略研究越来越成为研究者关注的课题。以秦皇岛市北戴河区民宿庭院景观为例,通过资料收集、实地调查、案例分析、总结归纳的方法,从生态有氧型、功能实用型、文化艺术型三个营造方向进行策略研究,总结出适于本地区滨海民宿庭院景观的设计方法和策略,以推动华北地区滨海民宿庭院景观的发展。 展开更多
关键词 滨海 庭院景观 民宿
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Impact,Mechanism,Monitoring of Land Subsidence in Coastal Cities(Annual Work of IGCP 663) 预览
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作者 YAN Xuexin YANG Tianliang +5 位作者 XU Yan Luigi TOSI Esther STOUTHAMER Heri ANDREAS LIN Jinxin HUANG Xinlei 《地质学报:英文版》 SCIE CAS CSCD 2019年第S01期158-159,共2页
Land subsidence is a worldwide geohazard consisting in the lowering of the ground surface due to natural and human-induced processes occurring in the shallow and deep subsoil.Over the last two decades,land subsidence ... Land subsidence is a worldwide geohazard consisting in the lowering of the ground surface due to natural and human-induced processes occurring in the shallow and deep subsoil.Over the last two decades,land subsidence has caused damages and widespread impacts to a variety of infrastructures in coastal cities(Ma et al.,2011;Liu et al.,2016;Minderhoud et al.,2018). 展开更多
关键词 LAND SUBSIDENCE COASTAL CITIES case studies reclaimed soil
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