Some aspects of Cretaceous ostracod biostratigraphy of South Africa and relationships with other Gondwanide localities

One hundred and thirty-six species, representing 67 genera have been recorded from the late Jurassic-Maastrichtian marine sediments of South Africa. The faunas show a major dichotomy across a regionally-developed late Cenomanian-early Coniacian hiatus with the Portlandian-Cenomanian Cytheruridae/Progonocytheridae/Schizocytheridae dominated faunas being replaced in the Coniacian by Trachyleberididae/Brachycytheridae/Schizocytheridae dominated faunas. Comparison with other Gondwanide localities shows that the two South African basins from which ostracods have been described (Outeniqua and Natal/Zululand) formed part of a Callovian-Cenomanian South Gondwana ostracod province that stretched from the Neuquen Basin of Argentina to Madagascar/Tanzania/Kutch and west Australia. The most characteristic and cosmopolitan forms within this province belong to the Majungaella/Amicytheridea/Progonocythere group, along with Arculicythere in the Aptian-Cenomanian.In Tanzania, (the only locality of the old South Gondwana province where the succession is complete) these assemblages are replaced in the Turonian by the influx of Brachycythere, and Cythereis and various other trachyleberids. Changes of a similar nature are seen whenever marine sedimentation resumed after the local “mid” Cretaceous hiatus (South Africa, India, Argentina). Argentina differs in not having Brachycythere, whose rapid appearance in the West Indian Ocean basin soon after its earliest record in Brazil, is attributed to the destruction of the barrier at the eastern end of the Walvis Ridge/Rio Grande Rise in late Cenomanian or early Turonian times. Despite this common element with Brazil and West Africa, the South African Coniacian to Maastrichtian faunas are closer to those of Tanzania and Australia than they are to either Argentina or Brazil/West Africa. In Zululand they show evidence of a steady increase in water depth, leading to the establishment of progressively more diverse cytheracean populations, with a particularly large increase across the Santonian/Campanian boundary.     

Impacts of sea-level rise and urbanization on groundwater availability and sustainability of coastal communities in semi-arid South Texas

The sea levels along the semi-arid South Texas coast are noted to have risen by 3–5 mm/year over the last five decades. Data from General Circulation Models (GCMs) indicate that this trend will continue in the 21st century with projected sea level rise in the order of 1.8–5.9 mm/year due to the melting of glaciers and thermal ocean expansion. Furthermore, the temperature in South Texas is projected to increase by as much as 4 °C by the end of the 21st century creating a greater stress on scarce water resources of the region. Increased groundwater use hinterland due to urbanization as well as rising sea levels due to climate change impact the freshwater-saltwater interface in coastal aquifers and threaten the sustainability of coastal communities that primarily rely on groundwater resources. The primary goal of this study was to develop an integrated decision support framework to assist land and water planners in coastal communities to assess the impacts of climate change and urbanization. More specifically, the developed system was used to address whether coastal side (primarily controlled by climate change) or landward side processes (controlled by both climate change and urbanization) had a greater control on the saltwater intrusion phenomenon. The decision support system integrates a sharp-interface model with information from GCMs and observed data and couples them to statistical and information-theoretic uncertainty analysis techniques. The developed decision support system is applied to study saltwater intrusion characteristics at a small coastal community near Corpus Christi, TX. The intrusion characteristics under various plausible climate and urbanization scenarios were evaluated with consideration given to uncertainty and variability of hydrogeologic parameters. The results of the study indicate that low levels of climate change have a greater impact on the freshwater-saltwater interface when the level of urbanization is low. However, the rate of inward intrusion of the saltwater wedge is controlled more so by urbanization effects than climate change. On a local (near coast) scale, the freshwater-saltwater interface was affected by groundwater production locations more so than the volume produced by the community. On a regional-scale, the sea level rise at the coast was noted to have limited impact on saltwater intrusion which was primarily controlled by freshwater influx from the hinterlands towards the coast. These results indicate that coastal communities must work proactively with planners from the up-dip areas to ensure adequate freshwater flows to the coast. Field monitoring of this parameter is clearly warranted. The concordance analysis indicated that input parameter sensitivity did not change across modeled scenarios indicating that future data collection and groundwater monitoring efforts should not be hampered by noted divergences in projected climate and urbanization patterns.     

Geological comparison of precambrian and early palaeozoic terrains between the Southern West Coast of Africa and the South-East Coast of South America

This paper describes a geological comparison of similar lithostratigraphic sequences of Proterozoic and early Palaeozoic ages between the southern west coast of Africa (Namibia and South Africa) and the south-east coast of South America (Brazil and Uruguay). The oldest terrains present within the compared regions are those comprising the Rio de la Plata and the Richtersveld Provinces of ~ 2000 Ma. Both provinces appear to have evolved from earlier Archaean terrains, i.e., the Guapore Craton in South America and the Kalahari Craton in southern Africa, during the Transamazonic and Eburnian orogenic cycles, respectively. Both the Namaqua Province, affected by the Kibaran orogenesis at ~ 1200 Ma, and the Sinclair Group of 1300 Ma seem to have no comparable geological counterparts in southern Brazil and Uruguay.The late Precambrian—early Palaeozoic successions of the Gariep and Ribeira belts investigated here seem to be remarkably similar and it is suggested that they were parts of the same geological unit, i.e., a mobile belt, developed during the Pan-African-Brasil- iano orogenesis. Geological comparisons are particularly good between the Gariep, Porongos and Lavalleja Groups, and stratigraphic correlations can be successfully at- tempted even between geological formations, i.e., Marica, Piedra de Afilar and Stink- fontein Formations.The lack of detailed geological maps for South America makes it difficult to separate different geological formations from broad lithostratigraphic successions and, consequent- ly, comparisons can only be drawn between subgroups and several geological formations, i.e., Vacacai and Minas Subgroups with Grootderm Holgat and Oranjemund Formations. The extensive magmatic activity generated during the Brasiliano orogenesis and only present in the south-east coast of South America has not affected the southern west coast of Africa. However, two post-tectonic complexes, i.e., the Kuboos—Bremen line of intrusives and the Sierra de Animas Complex appear to be geochronologically analogous and petrologically they seem to have certain similarities. It is also suggested that the Camaqua Group in southern Brazil and the Nama Group could perhaps have certain similarities within their lithological successions and their ages may be also com- parable.The late stages of the geological evolution of the basin, represented by molassic sediments, are only present in south-east Brazil. Finally an interpretation is given of the geological evolution of the Proterozoic—early Palaeozoic terrains compared in this work.     

Comparative urbanization in Ghana and Kenya in time and space

There are few inter-African country urban analyses because of the continent’s enormous size and socioeconomic diversity, language barriers, and wide variations in national and regional urban research capacity. Nevertheless, comparative urban studies are critical in understanding contemporary African urbanization. In this comparative spatial and temporal analysis of Ghana and Kenya’s urbanization, we find that both countries are urbanizing rapidly and are faced with many common urban problems. Moreover, Ghana is more urbanized than Kenya and has a larger indigenous urban imprint and a more widely dispersed urban pattern. Besides their physiographic and population conditions, we trace these countries’ convergent and divergent urban trends to their shared but unique experiences of colonialism, nationalism and globalization.     

城市下垫面空间特征对地表产汇流过程的影响研究综述

快速城市化显著改变了城市下垫面空间特征,对地表产汇流过程产生了重要影响。综述城市下垫面空间特征对地表产汇流过程的影响研究进展,以下垫面空间特征对产汇流过程的影响为主线,聚焦不透水面和微地形两类空间特征,总结城市下垫面空间特征及其表征方法;从不透水率与不透水面空间变化、数值模拟与物理实验等方面,分别梳理不透水面和微地形等空间特征对地表产汇流过程的影响研究成果。展望未来城市下垫面空间特征对地表产汇流过程的影响研究重点和发展方向,主要包括影响机理解析、主控空间特征参数识别与敏感性分析、城市水文效应适应性应对等,以期为快速城市化下城市水文效应解析和城市洪涝灾害防治提供一定参考。     

The effect of change in surface roughness on the precipitation regime in the coastal area of NE-Brazil

The NE of Brazil is one of the earth's problematic semiarid areas. However, in the coastal area along the coast from Natal to Salvador precipitation is high enough to allow for a fully developed tropical vegetation. It is shown that this enhancement of annual precipitation is due to the dynamic convergence within the planetary boundary layer and that this effect can quantitatively be evaluated by simple model considerations. To do this the mass flux perpendicular to the coastline is calculated within the lower troposphere for an undisturbed PBL (Planetary Boundary Layer) over land and over sea, by using the resistance law of the PBL and by integrating the equation of monion between the bottom and some height above the PBL. By using the equation of continuity the mean vertical motion due to the coastal convergence can be calculated. The relation of the calculated total amount of lifting near the coast on the rate of precipitation is calculated. Compared with the increase of precipitation due to orography it gives the same increase in precipitation per meter of lifting in the coastal area quantitatively and since this is strongly related to the roughness due to the vegetation along the coast it can be shown that deforestation — for instance to grow sugar-cane — in this area the annual amount of precipitation will decrease considerably. Once the coastal area will have been transformed to a desertlike structure, the coastal maximum of precipitation will diminish at all.     

我国城市化发展的新特点及其区域空间建设策略

经济全球化成为21世纪最具有广泛影响的事件,将促进全球城市化的高速发展。我国正处在城市化高度发展时期,城市化出现“集群式”发展、城乡二元结构扩大、“驱赶型城镇化”和城市化的区域空间差异性等新特点、新问题。我国快速城市化过程中出现的新矛盾、水土资源流失与大量占用,对沿海地区一些城市的区域环境产生了很多负面影响,诸如酸雨、城市污染、汽车烟雾和交通阻塞等。面对全球城市化的巨大影响与冲击,从区域空间角度出发,提出必须在科学发展观和构建和谐社会的指导下,使我国城市化走向健康之路,实施区域空间建设新策略,注重大城市群区内的保护与建设,因地制宜、合理利用、适度发展、构建区域性的生态安全格局,促进我国信息化的区域合作。     

Stenian A-type granitoids in the Namaqua-Natal Belt,southern Africa,Maud Belt,Antarctica and Nampula Terrane,Mozambique:Rodinia and Gondwana amalgamation implications

We carried out SHRIMP zircon U-Pb dating on A-type granitic intrusions from the Namaqua-Natal Province,South Africa,Sverdrupfjella,western Dronning Maud Land,Antarctica and the Nampula Province of northern Mozambique.Zircon grains in these granitic rocks are typically elongated and oscillatory zoned,suggesting magmatic origins.Zircons from the granitoid intrusions analyzed in this study suggest~1025-1100 Ma ages,which confirm widespread Mesoproterozoic A-type granitic magmatism in the Namaqua-Natal(South Africa),Maud(Antarctica) and Mozambique metamorphic terrains.No older inherited(e.g.,~2500 Ma Achean basement or~1200 Ma island are magmatism in northern Natal)zircon grains were seen.Four plutons from the Natal Belt(Mvoti Pluton,Glendale Pluton,Kwalembe Pluton,Ntimbankulu Pluton) display 1050-1040 Ma ages,whereas the Nthlimbitwa Pluton in northern Natal indicates older 1090-1080 Ma ages.A sample from Sverdrupfjella,Antarctica has~1091 Ma old zircons along with~530 Ma metamorphic rims.Similarly,four samples analysed from the Nampula Province of Mozambique suggest crystallization ages of~1060-1090 Ma but also show significant discordance with two samples showing younger~550 Ma overgrowths.None of the Natal samples show any younger overgrowths.A single sample from southwestern Namaqualand yielded an age of~1033 Ma.Currently available chronological data suggest magmatism took place in the Namaqua-Natal-MaudMozambique(NNMM) belt between~1025 Ma and~1100 Ma with two broad phases between~1060-1020 Ma and 1100-1070 Ma respectively,with peaks at between~1030-1040 Ma and~1070-1090 Ma.The age data from the granitic intrusions from Namaqualand.combined with those from Natal,Antarctica and Mozambique suggest a crude spatial-age relationship with the older1070 Ma ages being largely restricted close to the eastern and western margins of the Kalahari Craton in northern Natal,Mozambique.Namaqualand and WDML Antarctica whereas the younger 1060 Ma ages dominate in southern Natal and western Namaqualand and are largely restricted to the southern and possibly the western margins of the Kalahari Craton.The older ages of magmatism partially overlap with or are marginally younger than the intracratonic Mkondo Large lgneous Provinee intruded into or extruded onto the Kalahari Craton,suggesting a tectonic relationship with the Maud Belt.Similar ages from granitic augen gneisses in Sri Lanka suggest a continuous belt stretching from Namaqualand to Sri Lanka in a reconstituted Gondwana,formed during the terminal stages of amalgamation of Rodinia and predating the East African Orogen.This contiguity contributes to defining the extent of Rodinia-age crustal blocks,subsequently fragmented by the dispersal of Rodinia and Gondwana.     

Mobilizing the ethical consumer in South Africa

This paper presents a critical engagement with current initiatives for ethically-labeled goods in South Africa, thus offering an intervention in a literature on ethical consumption that has previously prioritized the global North. Through an interview-based methodology supported by focus groups in the Western Cape, the paper attends specifically to the strategies shaping recent forms of ethical consumption in South Africa on the part of business and civil society. Campaigns and strategies associated with three of the most prominent ethical labeling initiatives in South Africa—Proudly South African, Fairtrade Label South Africa and the Southern African Sustainable Seafood Initiative (SASSI)—are evaluated. Barnett et al.’s (2011: 90) notion of “mobilizing the ethical consumer” is brought into conversation with ethical consumption literature on local embeddedness in order to assess the ways in which the organizations responsible for these initiatives combine globalizing business and political networks of responsibility with local institutions and values in South Africa. The role played by the discursive construction of a growing South African ‘middle class’ is also acknowledged as part of the process of encouraging ethical consumption on the part of these actors. In conclusion, it is suggested that understanding ethical consumption in South Africa, as elsewhere, requires sensitivity to both transnational networks of globalizing responsibility and localized expressions of ethical consumption.     

海峡西岸城市群地质环境特征研究

福建南部沿海是全国城市化水平最高的地区之一,国内生产总值占福建省的51．64％,现已成为“海峡西岸经济区”建设的核心区域。城市是以人类社会为主体的生态系统,是城市社会(人口、劳动、智力)与城市空间(地质、资源、环境)对立统一的系统。区域地壳稳定是城市建设的基本条件,水是城市发展不可缺少的自然资源,闽南沿海花岗岩风化壳发育,软土环境工程地质问题突出。本文重点讨论城市区域稳定性问题、城市水资源供需平衡问题和城市开发建设可能涉及的工程地质问题。     

African urbanization in Metropolitan South Africa — differential urbanization perspectives

The supersession of the process of urbanization by what has been termed polarization reversal and counterurbanization in advanced developing and developed countries has become a much debated issue over the past 15 years. Disaggregated migration studies indicate that in addition to mainstream population migration patterns, undercurrent migration patterns may be evident which could differ quite substantially from the former. Such divergent migratory patterns occurring at the same time in the same country are called differential urbanization. As a potentially important urban development policy consideration, attention is focused in this paper on differential urbanization trends in South Africa at the metropolitan level. Recent informal urban settlement patterns of the African population within the major metropolitan areas are contrasted against these differential urbanization trends to determine the implications of both for residential development in the metropolitan areas during the post-apartheid era.     

A literary geography of Soweto

Humanist inspired literary geography offers one avenue of enquiry into the study of place. Its prime intention is to untangle the subjective, personalised construction and connotations of place meaning. African literature offers a rich source of information into the black urban experience. The presentation focuses upon the literary interpretation of Soweto, South Africa's largest black township. The Sowetan environment emerges as a landscape of placelessness in which the overwhelming emphasis by white and black writers alike is upon relating appalling conditions in an austere and hostile environment.     

青岛市城中村土地征用（收）调查

随着全国大部分地区尤其是东部沿海区域城市化发展进入加速期,城区土地资源紧张问题愈发显现。同时城区内大片旧城区和城中村的改造,影响着城市化能否顺利实施,为了破解这一城市发展难题,青岛市国土部门创新思路,探索实施新的城中村土地征用（收）办法,全方位保障被拆迁群众的利益,推动了城市化的顺利实施,促进了社会的和谐和城市经济健康发展。     

Estuaries of the South Atlantic coast of North America: Their geographical signatures

Estuaries of the southeastern Atlantic coastal plain are dominated by shallow meso-tidal bar-built systems interspersed with shallow sounds and both low flow coastal plain and high flow piedmont riverine systems. Three general geographical areas can be discriminated: the sounds of North Carolina; the alternating series of riverine and ocean dominated bar-built systems of South Carolina, Georgia, and northeast Florida, and the subtropical bar-built estuaries of the Florida southeast coast. The regional climate ranges from temperate to subtropical with sea level rise and hurricanes having a major impact on the region's estuaries because of its low and relatively flat geomorphology. Primary production is highest in the central region. Seagrasses are common in the northern and southern most systems, while intertidal salt marshes composed ofSpartina alterniflora reach their greatest extent and productivity in South Carolina and Georgia. Nuisance blooms (cyanobacteria, dinoflagellates, and cryptomonads) occur more frequently in the northern and extreme southern parts of the region. Fishery catches are highest in the North Carolina and Florida areas. Human population growth with its associated urbanization reaches a maximum in Florida and it is thought that the long-term sustainability of the Florida coast for human habitation will be lost within the next 25 years. Tidal flushing appears to play an important role in mitigating anthropogenic inputs in systems of moderate to high tidal range, i.e., the South Carolina and Georgia coasts. The most pressing environmental problems for the estuaries of the southeastern Atlantic coast seem to be nutrient loading and poor land use in North Carolina and high human population density and growth in Florida. The future utilization of these estuarine systems and their services will depend on the development of improved management strategies based on improved data quality.     

Challenging the gay ghetto in South Africa: Time to move on?

In recent years, there has been increasing interest in changes within gay ghettos, villages, precincts, and neighbourhoods in different cities and regions, particularly in the West. This includes concerns from some constituencies about the decline – or de-gaying – of some queer neighbourhoods, coupled with commentary about the emergence of newer places, sometimes espoused as mixed, gay-friendly, or post-gay. Drawing on the South African experience, the question of how central these debates should stand in gay geographical scholarship is posed. Although it is increasingly acknowledged that the “old gay ghetto debates” are in some ways parochial (both spatially and theoretically), the dominance of such concerns remains pervasive in Western gay space theorisation. In this paper, attention is focused on Western theorisations of the relationship between gay sexualities, its links to specific forms of gay space such as gay ghettos and neighbourhoods, and the South Africa context. The contention is that gay spaces (in the form of consolidated space, or villages) are not a necessary outcome of lived gay identities. It is argued that in South Africa differently constructed gay identities are differently spatialised and ultimately incongruent with Western theory. The investigation supports the growing scholarship that suggests Western theorisation of the links between gay sexual identity and space is not universally applicable.     

地理信息系统（GIS）在地质学中的应用

地理信息系统（ＧＩＳ）在最近５～８年中已普遍应用，它是在计算机上储存、编组和分析空间信息的系统。ＧＩＳ研究项目利用ＰＣＡＲＣ／ＩＮＦＯ软件处理地质和地理信息。自１９６０年以来，从南非海岸收集了大量海洋地质和地球物理信息，包括地震资料、声纳扫描、测深、磁法和重力记录，以及大量海底沉积物和岩石标本。这些资料对环境保护和矿产资源勘查方面的未来科学研究很有价值。目前这些信息难以利用，因为分析结果尚未能以一种方式储存可以直接相容。我们正在建立数据库，使用“ｄＢＡＳＥⅣ”和“ＰＣＡＲＣ／ＩＮＦＯ”以科学的、系统的方式连接各类地质和地球物理数据，从而提供利用这些信息的简单方便的方法。本文展示了南非西南海岸海洋沉积物分析的初步结果。扩大和改进数据库的研究正在进行。文中探讨了利用ＧＩＳ处理一般地质信息的可能性和优势。     

Urban experience takes an informational turn: mobile internet usage and the unevenness of geosocial activity

Coinciding the widespread deployment of handheld information and communications technologies (ICT) there has been a rapid emergence of mobile Internet applications. Notably, these applications are designed to perform within operating systems that are not only Internet-connected but that are also location-aware and decoupled from any single point in space—design characteristics that enable instantaneous integration of users’ everyday ‘real-world’ experience with an array of Internet-based services. As a consequence, the experience of urban space can be mediated by digital information in ways that have not before been possible. In this article I explore the convergence of ongoing discussions about the digital divide, the nascent class of mobile ICT, and the urban communities that have been most adversely impacted by uneven technological landscapes. Building on this convergence, I argue that it is increasingly important to consider the impacts that pervasive mobile information have on the composition of everyday urban life.     

The privatisation of secondary schooling and the desegregation of central Johannesburg

African education controlled by the state's Department of Education and Training has collapsed. Insufficient spending, low standards and persistent student boycotts have made township schools undesirable places of learning. African students with any financial means now seek secondary education at multi-racial private schools in affluent white suburbs or at street-academies in the centre of Johannesburg. The establishment of schooling services for African pupils in the traditionally white central business district contributes to the wider process of desegregation of South Africa's major urban area, Johannesburg.     

Interaction between land-use change,flooding and human health in Metro Vancouver,Canada

Many regions of the world are experiencing an increase in frequency and intensity of floods. There has been increasing understanding among emergency preparedness and natural disaster planners that rapid urbanization is enhancing the risk from river flooding in urban areas. Many regions of Canada have been exposed to particularly severe floods over the course of the last few years, much of this due to land-use change. This study aims at understanding the risk of flooding for the City of Metro Vancouver, British Columbia, Canada, which is located in the Fraser River Delta. The paper presents a fast, efficient and reliable method that can be used to produce vegetation maps from advanced very high resolution radiometer images and SPOT vegetation maps. A 10-day maximum normalized difference vegetation index maps were produced to assess the dynamics of the urbanization process in Vancouver. Remotely sensed data show a significant decrease in vegetation cover in the Metro Vancouver City between 1984 and 2012. The proposed method can be used as an effective tool for raising early land-use change awareness and assist with flood risk management. Flood risk management has a substantial impact on human health and well-being in urban areas, and this flood risk information will be used to assess the impact of flooding and explore the complex relationship between land-use change, urbanization, flooding and impact on urban dwellers.     

An Early Cretaceous extinct spreading center in the northern Natal valley

We have identified an extinct E–W spreading center in the northern Natal valley on the basis of magnetic anomalies which was active from chron M11 (133 Ma) to 125.3 Ma, just before chron M2 (124 Ma) in the Early Cretaceous. Seafloor spreading in the northern Natal valley accounts for approximately 170 km of north–south motion between the Mozambique Ridge and Africa. This extension resolves the predicted overlap of the continental (central and southern) Mozambique Ridge and Antarctica in the chron M2 to M11 reconstructions from Mesozoic finite rotation parameters for Africa and Antarctica. In addition, the magnetic data reveal that the Mozambique Ridge was an independent microplate from at least 133 to 125 Ma. The northern Natal valley extinct spreading center connects to the spreading center separating the Mozambique Basin and the Riiser-Larsen Sea to the east. It follows that the northern Mozambique Ridge was either formed after the emplacement of the surrounding oceanic crust or it is the product of a very robust spreading center. To the west the extinct spreading center connects to the spreading center separating the southern Natal valley and Georgia Basin via a transform fault. Prior to chron M11, there is still a problem with the overlap of Mozambique Ridge if it is assumed to be fixed with respect to either the African or Antarctic plates. Some of the overlap can be accounted for by Jurassic deformation of the Mozambique Ridge, Mozambique Basin, and Dronning Maud land. It appears though that the Mozambique Ridge was an independent microplate from the breakup of Gondwana, 160 Ma, until it became part of the African plate, 125 Ma.