闽东滨海湿地生态系统服务功能价值评估   总被引：4，自引：1，他引：3  

苏少川  何东进  王韧  蔡金标  林立  廖小娟  张中瑞  陈志文  黄鹏 《湿地科学与管理》2012,8(3):14-18

以闽东滨海湿地为研究对象,在实地调查和查阅相关资料的基础上,将闽东滨海湿地生态系统划分为水域、潮间裸滩、农田、人工库塘和养殖场5个类型,确定物质生产、气候调节、水文调节、污染净化、生物栖息地、教育科研以及休闲旅游为闽东滨海湿地生态系统主导的服务功能,并采用市场价值法、造林成本法、影子工程法、费用替代法以及碳税法等方法来评估各项生态系统服务功能价值。结果表明:闽东滨海湿地生态系统的服务功能总价值量为1510262万元,其中物质生产功能的价值量最大,为856701万元,其次是污染净化的功能价值,为448844万元。  相似文献   

江苏东部沿海五大地学景观          下载免费PDF全文

朱士鹏  周晓丹  赵剑畏  庄颖 《江苏地质》2009,33(3):320-324

赣榆秦山岛“神路”、连云港云台山海蚀洞、北北西向淤泥质断层海岸线、辐射状沙洲和东台谅港“两分水”以及海门东灶蛎蚜山牡蛎礁是江苏东部沿海五大地学景观,对它们的研究和开发具有重要的理论价值和实际意义。  相似文献   

Modelling the formation of residual dune ridges behind barchan dunes in North-east Brazil     

NOAM LEVIN  HAIM TSOAR†  HANS JÜRGEN HERRMANN‡  §  LUIS P. MAIA¶  VANDA CLAUDINO-SALES 《Sedimentology》2009,56(6):1623-1641

Residual dune ridges are often formed by vegetation growing along a line some distance upwind of the lower stoss slope of migrating dunes. This process is common in areas where vegetation germinates along the edge of the water during the rainy period when the water level is higher and interdune areas are flooded. The phenomenon occurs on a large scale in North‐east Brazil, because of the rise and fall in groundwater level at the end of the rainy season. Each residual dune ridge corresponds to the position of the dune during the wet period in each year. Therefore, variations in the distance between these residual dune ridges could be used potentially to monitor climatic fluctuations in rainfall and wind. To examine the potential use of these residual dune ridges for the reconstruction of past climatic fluctuations, a model that simulates them under varying conditions of wind, rainfall and evaporation rates was formulated. The model was tested for sensitivity to climatic variability in North‐east Brazil and validated against residual dune ridge displacements as measured in the field and from high spatial resolution satellite images. Based on the results, it is concluded that residual dune ridges may not form in North‐east Brazil in years which are exceptionally dry, as may happen during El‐Niño events. When this type of event happens, the distance between adjacent residual dune ridges corresponds to more than one year and, therefore, the correlation between dune displacements and wind power becomes weak or even disappears. Additionally, because of biotic, aeolian and hydrological processes, these arcuate residual dune ridges may not preserve their initial shape for long periods. The presence of residual dune ridges testifies to the temporary flooding which may or may not be seasonal. However, the potential for using residual dune ridges to reconstruct the palaeo‐climate of wind regime on a yearly basis or to identify past El‐Niño events seems to be limited.  相似文献   

A short note on the geo-archeological significance of the ancient Theodosius harbour (İstanbul, Turkey)     

Oya Algan  M. Nam&#x;k Yal&#x;n  Mehmet zdoan  &#x;sak Y&#x;lmaz  Erol Sar&#x;  Elmas K&#x;rc&#x;-Elmas  Demet Ongan   zlem Bulkan-Yeiladal&#x;  Yücel Y&#x;lmaz  &#x;smail Karamut 《Quaternary Research》2009,72(3):457-461

The sedimentary sequence discovered at archaeological excavations in ancient Theodosius Harbour at İstanbul contains the records of sea level, environmental changes and the cultural history of the region. The cobbles at the base of the sequence include archaeological remnants of Neolithic culture that settled in the area between 8.4 and 7.3 ¹⁴C ka BP, and are located at 6 m below the present sea level. The sediments representing a coastal environment indicate that the area was used as a harbour from AD 4th to at least the 11th century and were filled by the sediments derived from Lykos Stream after 11th century.  相似文献   

The use of geoprocessing to assess vulnerability on the east coast aquifers of Rio de Janeiro State,Brazil   总被引：1，自引：0，他引：1  

Vinicius Silva Seabra  Gerson Cardoso da SilvaJr  Carla Bernadete Madureira Cruz 《Environmental Geology》2009,57(3):665-674

The east coast of Rio de Janeiro State, Brazil, shows a worrying overlap between areas with intrinsic groundwater vulnerability and the most significant urban expansion zones. It experienced a rapid population growth in recent years, mainly due to the tourism industry, resulting in a significant pressure on drinking groundwater resources. In this regard, development and use of techniques to control and protect areas susceptible to contamination is crucial. The elaboration of aquifer vulnerability maps is thus extremely helpful to support water resources management. The aim of the work is to present the methodological approach in the use of Geoprocessing techniques to obtain a suitable groundwater vulnerability model in Rio de Janeiro east coast. Considering the existing problems and the current land use and characteristics of the study region, it is clear that the most vulnerable areas (that is, “extreme” and “very high” vulnerability areas), coincide with the most significant zones of urban occupation, corresponding to 11% of the total study area, demanding adoption of urgent measures in the near future. Geoprocessing tools and remote sensing for characterization of Rio de Janeiro’s east coast aquifer vulnerability gave good results, representing a satisfactory method for management actions at low cost.  相似文献   

东南沿海晚白垩世火山岩浆活动特征及其构造背景   总被引：15，自引：2，他引：13  

邢光福  陈荣  杨祝良  周宇章  李龙明  姜杨  陈志洪 《岩石学报》2009,25(1):77-91

东南沿海晚白垩世火山岩浆活动微弱,研究程度不高,但构造意义重要。对浙闽沿海晚白垩世小雄组和石牛山组火山岩及其共生侵入岩类进行了较系统研究。测得小雄破火山中央侵入相正长斑岩和石牛山破火山中央侵入相正长花岗斑岩的锆石年龄分别为87.9±1.2Ma和93.8±1.3Ma;岩石学和地球化学特征表明,小雄组和石牛山组火山岩及其共生侵入岩类均属后造山A型花岗质岩类,它们是在东南沿海巨型白垩纪A型花岗岩带主体形成之后、岩石圈进一步强烈伸展的背景下形成的,是区域中生代最晚期的酸性火山岩浆活动产物,标志着燕山造山过程最终结束于约90Ma。  相似文献   

“It’s a gestalt experience”: Landscape values and development pressure in Hawke’s Bay, New Zealand     

Damian Collins  Robin Kearns 《Geoforum》2010,41(3):435-446

Demand for both primary residences and second homes in high-amenity areas has led to escalating property values and widespread development pressure in coastal New Zealand. We focus on a major development proposal at Ocean Beach, a greenfield coastal site in the Hawke’s Bay region, and seek to explain the opposition it has provoked. In so doing, we address three questions: first, what landscape values are articulated within the planning process; second, what is the anticipated impact of 1000 new dwellings on those values; and third, how does place attachment figure in the ensuing debates. We address these questions though a thematic analysis of data derived from official reports and proposals, planning submissions, and key informant interviews. We find Ocean Beach to be a place that offers a quintessential coastal experience, often linked to youthful memories. Additionally, the site is valued for its accessibility and wilderness qualities - perceptions heightened by awareness that areas of undeveloped coastline relatively close to population centres are increasingly scarce. We contend that such sites are doubly valuable: in a formal sense, as natural landscapes whose processes and forms receive regulatory protection; and in an informal sense, as sites that generate human meaning, including emotions such as nostalgia, freedom and belonging.  相似文献   

Hydrodynamics in Holocene Lake Mega-Chad     

Frédéric Bouchette  Mathieu Schuster  Claude Roquin  Patrick Marsaleix 《Quaternary Research》2010,73(2):226-236

Holocene Lake Mega-Chad (LMC) was the largest late Quaternary water-body in Africa. The development of this giant paleo-lake is related to a northward shift of the isohyetes interpreted as evidence for an enhanced Monsoon (African Humid Period). Numerous preserved coastal features have been described all around the LMC shore. Such features reveal the main paleo-hydrodynamical tendencies. In the context of a closed water-body like LMC, hydrodynamics are forced mainly by winds. We use a three-dimensional numerical model (SYMPHONIE) to simulate the mean hydrodynamics in LMC under both Harmattan-like (northeasterly trade winds) and Monsoon-like (southwesterly winds) forcings. The northern part of LMC displays coastal features, such as sand spits, that are consistent with the simulations forced by Harmattan-like winds. Geomorphic features related to Monsoon-driven hydrodynamics are not clearly expressed. They could have developed during the early stage of LMC but subsequently reworked. At the time of sand-spit building, Harmattan-like driven hydrodynamics prevailed and related coastal features were preferentially preserved in the sedimentary record.  相似文献   

The Promise for Geomorphic Discovery in the South     

《The Journal of geography》2012,111(4-5):151-161

Abstract

Until recently a neglected region, renown for limited exposures, the southern United States is becoming an area of geomorphic discovery. This article presents an overview of current geomorphic research in this region, suggesting that despite past problems, academic geographers have made significant contributions to the geomorphology of the South in recent years. Research topics published on the region are highly varied, with some spatial bias as well as topical bias toward fluvial systems. Yet because of the limited historical work, much is unknown about these unique landscapes and their susceptibility to natural and human disturbances, and much benefit is to be gained from both applied and theoretical study of them.  相似文献   

The role of strong earthquakes and tsunami in the Late Holocene evolution of the Fortore River coastal plain (Apulia, Italy): A synthesis     

Giuseppe Mastronuzzi  Paolo Sansò 《Geomorphology》2012,138(1):89-99

Morphological analysis of the Fortore River coastal plain and the Lesina Lake coastal barrier integrated with radiocarbon age data indicates that the evolution of the coastal landscape has been strongly affected by a number of strong earthquakes and related tsunamis which occurred during the last 3000 years. The first seismic event struck this coastal area in the V century BC. It produced strong erosion of the Fortore River coastal plain and significant emersion of Punta delle Pietre Nere, as well as the large tsunami responsible for the development of the Sant'Andrea washover fan. The second event occurred in 493 AD; it induced severe erosion of the Fortore River coastal plain and triggered the large tsunami that hit the Lesina Lake coastal barrier, producing the Foce Cauto washover fan. Then later in 1627, an earthquake was responsible for the further coseismic uplift of Punta delle Pietre Nere, the subsidence of Lesina village area and the development of a tsunami which produced two washover fans.Morphological analysis points out that seismic events strong enough to control the morphological evolution of local coastal landscapes show a statistical return period of about 1000 years. These major events produced important coseismic vertical movements and large tsunamis. However, the correct identification of the tectonic structure responsible for the generation of these strong earthquakes is still an unsolved problem.  相似文献