Locational components of urban and regional public policy in postwar Vietnam: The case of Ho Chi Minh city (Saigon)

Ho Chi Minh city is a primate city in which wartime dislocations have resulted in severely overcrowded conditions as well as a shrunken economic base. The new government has opted for a policy based on the rapid decanting of a large proportion of the urban population by encouraging internal migration to New Economic Zones in the hinterlands. This policy is based on a hierarchial administrative structure with agricultural productivity as its prime goal. A Green Belt policy has been articulated that uses the New Economic Zones as building blocks. The Green Belts constrain urban growth as well as provide foodstuff for the remaining urban residents. The ultimate objective of the overall policy is a balanced urban and regional environment that is in tune with Vietnam's agricultural economy.     

Monitoring and predicting land use change in Tripoli Metropolitan City using an integrated Markov chain and cellular automata models in GIS

The rapid development of cities in developing countries results in deteriorating of agricultural lands. The majority of these agricultural lands are converted to urban areas, which affects the ecosystems. In this research, an integrated model of Markov chain and cellular automata models was applied to simulate urban land use changes and to predict their spatial patterns in Tripoli metropolitan area, Libya. It is worth mentioning that there is not much research has been done about land use/cover change in Libyan cities. In this study, the performance of integrated CA–Markov model was assessed. Firstly, the Markov chain model was used to simulate and predict the land use change quantitatively; then, the CA model was applied to simulate the dynamic spatial patterns of changes explicitly. The urban land use change from 1984 to 2010 was modelled using the CA–Markov model for calibration to compute optimal transition rules and to predict future land use change. In validation process, the model was validated using Kappa index statistics which resulted in overall accuracy more than 85 %. Finally, based on transition rules and transition area matrix produced from calibration process, the future land use changes of 2020 and 2025 were predicted and mapped. The findings of this research showed reasonably good performance of employed model. The model results demonstrate that the study area is growing very rapidly especially in the recent decade. Furthermore, this rapid urban expansion results in remarkable continuous decrease of agriculture lands.     

Urban geology of boulder,colorado: A progress report

A cooperative program in urban geology between the city of Boulder, Colorado, and the Department of Geological Sciences, University of Colorado, has been in effect since late 1969. The principal geological problems in the rapidly growing urban environment of Boulder include:

1. Swelling clays in the Pierre Shale have been related to foundation failure, pavement heaving, and landsliding on hillslopes.
2. Colluvium and ancient landslides have been made unstable by removal of support, by loading with buildings or fill, and by increases over natural moisture contents through lawn watering and septic-tank seepage.
3. Flooding on high-gradient mountain streams has been caused by sedimentation induced by the constriction of natural channels through urban development. In May, 1969, Bear Canyon Creek overflowed its banks with a discharge of less than one-fifth its design capacity. Flooding was caused by coarse bedload deposited upstream from a culvert.

The Boulder city geologist collects data on soils exposed in open excavations within the city, maps ancient and modern landslides, provides information for contractors bidding on public works projects, and reviews the geologic aspects of all consulting work prepared for the city. Examples of formats used for the communication of information to responsible city officials include geotechnic maps of all open cuts, street pavement design maps, and input into the city-wide standard specifications for enginnering projects.     

Polycyclic aromatic hydrocarbons in surface sediments of Binacional Itaipu Lake,Brazil: characteristics,sources and toxicity evaluation

Itaipu Lake, which includes the Itaipu hydroelectric power plant, is one of the largest dams in the world and has a strong relationship with its surroundings. The flooded area has multiple uses such as navigation, recreation, water abstraction for industrial, urban and agricultural irrigation. The lake is located at the frontier between Brazil, Argentina and Paraguay. In this study, superficial sediments collected from nine sampling sites were analysed for grain size, organic matter and 16 priority polycyclic aromatic hydrocarbons (PAHs) using high-performance liquid chromatography (HPLC) with fluorescence detector. The total concentration of PAHs in the dry sediment ranged from 35.21 to 685.37 µg kg^?1. Diagnostic ratios showed that the possible source of PAHs in the Itaipu Lake could be pyrolitic and petrogenic. The potential toxicity of sediment of PAHs varied from not detected to 127.70 µg g^?1, suggesting that some adverse ecological effects would arise due to PAHs in these sediments.     

Helsinki —aspects of urban development and planning

Within a typical process of urbanization several particularities can be noticed in the Helsinki region: The peninsular location does not allow a zonal expansion of the city. It has rather enforced a tight spatial sectoral expansion with specific problems of traffic and land use. The retarded industrialization has led to an unusually fast population increase without control until the 1960s. The rapid growth created a twofold problem: pressure of population versus inadequate housing, small residences versus high rents; consequently selective migration and small size families. The number of jobs rapidly increased and displaced the residential population of the inner city. This resulted in high traffic which neither the few main roads nor the public transport system of central Helsinki could cope with. These problems correspond to the essential tasks of urban planning: the bottle neck in housing construction has to be broken; the growth of jobs in the central city needs to be stopped as well as the displacement of the residential population. Decentralization, especially of the private tertiary and quartary sector may help. A system of central places within the region would diminish the commuting traffic. Transportation may be solved by a concept of growth points and growth axis along the railway lines. This grown concept of Helsinki should be thought over under the now foreseeable conditions of population stagnation.     

P’yŏngyang — ancient and modern —the capital of North Koreangyang — ancient and modern —the capital of North Korea

The capital of the Democratic People’s Republic of Korea (North Korea) is both the oldest and the newest settlement in Korea. The basic concepts in its early urban development made it the model for Korean cities of later ages. In the 6th and 7th century AD P’yôngyang was one of the largest cities in Asia, second only to the imperial capital of China, but it later declined. It partly recovered its former position when it became the capital of North Korea after World War II. Its reconstruction since the Korean War has made it one of the most striking examples of socialist city planning.     

Boninite primary magmas: Evidence from the Cape Vogel Peninsula,PNG

Boninites from Cape Vogel, PNG, are dominantly pyroxene-glass rocks, but many contain olivine, sometimes as refractory as Fo₉₄. We derive a parental magma for this suite (in equilibrium with Fo₉₄) which contains 20 wt.% MgO and is quartz-normative. This liquid is hydrous, and from petrographie evidence and whole rock H₂O⁺ values, we estimate it to contain 2–3 wt.% H₂O. These data suggest olivine fractionation and primary magmatic water are important in boninite genesis, but both are often obscured by later alteration. The derived parental magma has probably formed at 1,250–1,300° C and low pressures (< ?10kB) and is similar to those which gave rise to olivine-clinoenstatite phyric boninites from New Caledonia and from Howqua, Australia, and possibly to a proposed parental magma for the Bushveld Complex.     

Metal contamination of surface sediments of the Sfax–Chebba coastal line,Tunisia

Concentrations of several heavy metals (Pb, Cr, Cd, Cu, Zn and Fe) in surface sediment were determined to investigate the distributions and the metallic pollution status in Sfax–Chebba coastal area (southeast of Tunisia). Sediment samples were collected from 20 locations, representing three different site groups (i.e., site I: urban zone, site II: pre-urban zone and site III: rural zone). Heavy metal contents were analyzed by Atomic Absorption Spectrometry. The obtained results showed that generally, heavy metal concentrations in the coastal sediments near Sfax city (urban zone) were higher than those at other stations because of the anthropogenic activities. These concentrations exceeded the threshold effect levels. This was confirmed by the chemometric approaches (enrichment factors, geoaccumulation index and principal component analysis) which showed a significant impact of multiple anthropogenic sources. Moderate to extremely severe enrichment of sediments in terms of Pb, Cr, Cd, Cu and Zn were shown to exist in site I. Severe enrichment by Cd was also observed in other sites. Based on the geoaccumulation index, Pb, Cr, Cd, Cu and Zn can be considered as unpollutants to extreme pollutants.     

Towards hydrological and geochemical understanding of an ephemeral palustrine perched water table “wetland” (Lanseria Gneiss,Midrand, South Africa)

Wetland delineation is commonly based on terrain unit, soil form, soil wetness and vegetation indicators which along with the shallow groundwater or proximate surface water are often absent in many ephemeral inland South African areas due to, for instance, prolonged dry periods (seasons to years) which mask these indicators, as well as disruption of surface materials due to construction, agricultural activities and field fires. Furthermore, many “wetlands” in South Africa comply with the four indicators, but the notable absent requirement for wetlands is missing, namely the shallow groundwater table, as many of these systems form in hillslope seeps, catenas or from perched water tables. A 200-m-long excavation through one such a system is being studied in Midrand (Gauteng, South Africa). The site is underlain by Lanseria Gneiss and is waterlogged after long and intense periods of intense rainfall. Frequent downslope soil profiling, horizon-specific laboratory analyses for grading and Atterberg Limits, X-Ray Diffraction and X-Ray Fluorescence Spectroscopy data are interpreted together with soil percolation tests to generate a conceptual model of the system. The results are discussed in terms of the need to consider these temporary systems that do not have a shallow groundwater table and that are not in direct contact with surface drainage features as a possible special type of wetlands, notably in arid regions where they play a very important role in biodiversity and should, therefore, be protected.     

New contributions to the Upper Senonian stratigraphy in Northern Iraq

The Upper Senonian sediments are well developed in Northern Iraq and represent three types of facies; elastics, reefal, and open-marine. These sediments are classified stratigraphically depending upon similarities in age and lithology. New groups are proposed for the first time; Ruwanduz Reefal Group comprising Aqra Limestone Formation, Bekhme Limestone Formation and Pilsener Limestone Formation, and Zakho Marl Group including Shiranish Formation, Digma Formation and Jib'ab Formation. It is suggested here that Jib'ab Formation is an extension of the Shiranish Formation and should not be treated as a separate lithostratigraphic unit.     

Sources and history of PAHs in lake sediments from oil-producing and industrial areas,northeast China

Abundance, sources, and historical records of polycyclic aromatic hydrocarbons (PAHs) in sediment cores of three lakes located in northeast China were evaluated. One lake was located in a rural oil field area, one in an industrial urban oil field area, and the third in an urban industrialized area without oil field influence. Cores from each lake were divided into 1-cm sections, dated using ¹³⁷Cs techniques, and 16 priority PAH compounds were measured. Total PAH concentrations were greater in industrial areas than in rural area, regardless of associated oil production. Only petroleum sources of PAHs were identified in lakes near oil fields between 1950s and 1980s, while sources of liquid fossil fuel combustion were persistently identified in the industrial urban lake. From 1990s to 2000s, PAH concentrations, especially high molecular weight PAHs, significantly increased in all lakes, which were consistent with the economic development in China, suggesting a change in energy use from wood burning and petroleum (oil) to liquid fossil fuel combustion. Environmental risk was low to moderate in sediments of the three lakes studied, and increases in high molecular weight PAHs during 1900s–2000s is a concern.     

Success factors of enhanced disaster resilience in urban community

Due to its unique geographic environment, Taiwan is prone to natural disasters such as earthquakes and typhoons that can cause heavy casualties and huge property losses. The effects of global warming have also increased extreme climate events and the frequency and severity of natural disasters. Therefore, disaster prevention/mitigation and response is not only an important government policy issue, but also an important daily life issue. To increase the awareness of natural disasters and the importance of community safety, the Taiwan government actively promotes a community disaster prevention system. However, to avoid over-reliance on the government taskforce, the spontaneous participation and cooperation within communities can complete specific disaster preparedness and reinforce local resources for disaster prevention and response. Although the concept of disaster-resilient community (DRC) has been shaped for a long period of time, community residents cannot keep pace with the government, which may decrease the effectiveness of DRC development. Therefore, theoretical and practical studies of urban DRC become imperative. This qualitative case study used the participant observation method to collect relevant empirical data by performing action research with self-reflection. Particularly, this article is supplemented by service work experience of the researchers in DRC promotion. A qualitative analysis of case communities during training in disaster preparedness revealed the critical success factors (CSFs) affecting the level of community-based disaster prevention and protection works. Based on the literature and empirical data, the CSFs are discussed through three spindle constructs: coping strategy, operations management, and organizational behavior. Finally, the conclusions and suggestions are given for promoting sustainable DRC.     

Seismic risk assessment of the 3rd Azerbaijan gas pipeline in Iran

A comprehensive seismic risk assessment has been performed for the existing route of the 3rd Azerbaijan natural gas buried pipeline in Iran. The major active seismic sources along the pipeline were identified and the geometrical parameters as well as the seismicity rates were determined. The seismic hazard assessment of the ground vibrations along the pipeline was performed in the framework of the Probabilistic Seismic Hazard Analysis using the CRISIS 2007 software. All of the components of the gas pipeline along the route were identified and the corresponding fragility functions are established through the methodology described in the HAZUS guideline (HAZUS MH MR4 Technical manual 2007 Department of homeland security emergency. Preparedness and Response Directorate, FEMA). A detailed cost analyses was taken into consideration based on the expert opinions in the National Iranian Gas Company, in order to provide more practical loss model for the pipeline route. Also, a simple method is suggested in order to account for the vent gas in the total loss estimation. The spatial analysis of the hazard function layer in combination with the loss model layer, in Geographical Information System  (GIS) platform, reveal the financial consequences of different earthquake scenarios.     

The problem of rock assimilation by Somma-Vesuvius magma

New chemical and modal analyses are presented of magmatic rocks and pyroxenes nodules from the Somma-Vesuvius volcano and of trachytes from the surrounding area. Geochemical evidence is employed in checking the generally accepted suggestion that magma composition develops from that of trachyte into phonolitic tephrite and finally into tephritic leucitite (vesuvite) by assimilation of dolomite. At the Somma stage of the volcano, phonolitic tephrites (tephritic phonolites) alone have been produced. Vesuvius lavas (tephritic leucitites) are comparatively high in K₂O, CaO, F, Cl, Mn, Cu, Sr and Ba and low in SiO₂ and Nb. The formation of vesuvites by assimilation of dolomitic sedimentary rocks, combined with gravity-separation of early-formed pyroxenes from a trachytic or tephritic magma, is improbable as shown by chemical balances between the respective igneous and sedimentary rocks.     

Phylogenetic Problems in Polynesian Simuliidae (Diptera: Culicomorpha): A progress report

As a basis for eventual control of the vicious anthropophilic and ornithophilic simuliid females of the Marquesas Islands, a taxonomic revision of Polynesian Simuliidae is in progress. Cytotaxonomic studies reveal two simuliid species in Rarotonga, Cook Islands; nine species in Tahiti, Society Islands, and two in the Marquesas Islands. A cytophylogeny is now available. Polynesian Simuliidae are unique in possessing heterogametic females. A reconstructed phylogeny, based mainly on morphological character states of larvae and pupae, agrees well with the cytophylogeny. One of the new species which is closely related to Simulium oviceps Edwards has larvae with highly reduced, non-functional cephalic fans. Ages of the Polynesian islands are discussed in relation to possible dispersal of Simuliidae into Polynesia.     

Application of Monte Carlo simulation technique for flood estimation for two catchments in New South Wales,Australia

The currently adopted rainfall-based design flood estimation method in Australia, known as design event approach (DEA), has a flaw that is widely criticized by the hydrologists. The DEA is based on the assumption that a rainfall depth of a certain frequency can be transformed to a flood peak of the same frequency by adopting the ‘representative values’ of other model input variables, such as temporal patterns and losses. To overcome the limitation associated with the DEA, this paper develops stochastic model inputs to apply Monte Carlo simulation technique (MCST) for design flood estimation. This uses data from 86 pluviograph stations and six catchments from eastern New South Wales (NSW), Australia, to regionalize the distributions of various input variables (e.g., rainfall duration, inter-event duration, intensity and temporal patterns and loss and routing characteristics) to simulate thousands of flood hydrographs using a nonlinear runoff routing model. The regionalized stochastic inputs are then applied with the MCST to two catchments in eastern NSW. The results indicate that the developed MCST provide more accurate flood quantile estimates than the DEA for the two test catchments. The particular advantage of the new MCST and stochastic design input variables is that it reduces the subjectivity in the selection of model input values in flood modeling. The developed MCST can be adapted to other parts of Australia and other countries.     

A cordierite-bearing granite suite from the New England Batholith,N.S.W., Australia

A suite of cordierite-bearing biotite-muscovite intrusive granites in the New England Batholith, New South Wales, outcrops over 3400 sq km and is the largest reported occurrence of granites of this type. Compositionally the granites are close to the low temperature minimum and display only limited chemical variation. The corundum-normative nature of the granites suggests a pelitic sedimentary parentage. Cordierite with an average 100 Mg/ Mg + Fe of 55 occurs as large tabular crystals and is considered to be a refractory phase brought up from the zone of partial melting. The presence of cordierite and the absence of garnet in these granites suggests a partial melting at a pressure maximum of 6 kb, equivalent to 22 km depth.     

A benthic chamber for intensely metabolic lotic systems

We have designed a flow-through benthic chamber that has the desirable characteristics of: simulation of tidal currents, continuous operation, ability to measure photosynthesis, respiration and nutrient exchanges, and maintenance of near-ambient oxygen conditions in a highly metabolic environment. The apparatus is based on a 1.3 m long Plexiglas tunnel, closed at bith ends, with both constant circulation and periodic flushing. The results of a 9-month study at one location in Flax Pond, a Long Island, New York, tidal pond, show large seasonal variations, influences of both sunlight intensity and seasonality, and a P/R ratio of less than one.     

Geochemistry of cumulus peridotites and gabbros from the Marum ophiolite complex,northern Papua New Guinea

The layered cumulus rocks of the Marum ophiolite complex in northern Papua New Guinea range from highly magnesian dunite, wehrlite, and lherzolite through pyroxenite to norite-gabbro with minor anorthosite and ferronorite-gabbro near the top of the sequence. Most of the cumulates, particularly the gabbroic rocks, are characterised by recrystallised adcumulus textures and all intercumulus melt (mesostasis) has been expelled. Trends in the cumulate sequence from Mg-rich to more Fe-, Ca- and Al-rich compositions are consistent with the formation of the layered sequence by magmatic accumulation from mafic tholeiitic magmas with varying degrees of differentiation. The cumulates are characterised by extremely low levels of ‘incompatible’ elements (K, Ba, Rb, P, Zr, Nb, Hf, Y and REE) at all levels of differentiation. REE patterns are strongly depleted in LREE; HREE abundances range from ≦0.3 chondrites in peridotite to 3 x chondrites in the norite-gabbros. The Marum cumulates resemble low-Ti peridotites and gabbros found in other orthopyroxene-bearing ophiolite sequences. The parent magmas of the Marum cumulates are inferred to have been strongly depleted in ‘incompatible’ trace elements (～ 2,000 ppm Ti, ～20 ppm Zr, 6–9 x chondrites HREE with La_N/Sm_N～0.5). These abundances are lower than found in typical MORB and back-arc basin basalts or their picritic parents. The dissimilarity of trace element abundances of the inferred Marum parent magmas with MORB-type high-alumina olivine tholeiites supports the conclusion drawn previously from the petrology of the cumulates that the parent magmas to the Marum ophiolite were not of MORB composition but resembled the strongly depleted, Ni-rich magnesian olivine-poor tholeiites and quartz tholeiites of the Upper Pillow Lavas of the Troodos ophiolite. The Marum parent magmas are believed to have been formed by shallow melting of refractory peridotite, and are chemically and genetically distinct from the LREE-enriched high-Ti lavas (Tumu River basalts) which occur in faulted contact. The geochemical data do not permit unequivocal assignment of a tectonic environment for the formation of either the Tumu River basalts or the plutonic suite; their juxtaposition results from thrust emplacement.