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1.
The demise of South African Apartheid Planning in 1994 and subsequent lost of Umtata’s capital status when the Transkei was subsumed into the new Eastern Cape Province resulted in the major political transformation of the Transkei state. Central to the post-apartheid transformation was restructuring of Transkei bureaucracy which at the time of South Africa’s independence in 1994 displayed abnormalities. This paper documents the restructuring of the Transkei bureaucracy focusing on Umtata since 1994. The study has brought to the forefront the following facts: Firstly, that at the time of the Transkei merger into South Africa, employment in the government was ‘booming’ and to greater extent it was affected by Umtata’s role—being the capital city of the pseudo-Transkei state. Secondly, the post 1994-political transformation of the Transkei Bantustan impacted negatively on Umtata’s employment notably the civil service sector by ‘squeezing’ it during the early years of democracy (1994–2000). Thirdly, since 2001, with Umtata serving as the major urban centre of both King Sabata Local Municipality and OR Tambo District Municipality, employment in the civil service and municipality has been revitalized.  相似文献   

2.
Stream response to subsidence from underground coal mining in central Utah   总被引:1,自引:0,他引:1  
 Short-term geomorphic and hydrologic effects of subsidence induced by longwall mining under Burnout Creek, Utah were evaluated. During the year after longwall mining, 0.3–1.5 m of subsidence was measured near impacted reaches of the mountain stream channel. The major channel changes that occurred in a 700-m reach of Burnout Creek that was subsided from 1992 to 1993 were: (1) increase in lengths of cascades and to a lesser extent glides; (2) increases in pool length, numbers and volumes; (3) increase in median particle diameter of bed sediment in pools; and (4) some constriction in channel geometry. Most of the changes appeared short-lived, with channel recovery approaching pre-mining conditions by 1994. In a 300-m reach of the South Fork that was subsided from 1993 to 1994, only channel constriction was observed, although any impacts on pool morphology may have been confounded by heavy grazing in the riparian reaches during the dry summer of 1994. Similar near-channel sedimentation and loss of pool volume between 1993 and 1994 were noted throughout Burnout Creek and in adjacent, unmined James Creek. Subsidence during the 3-year period had no effect on baseflows or near-channel landslides. Received: 10 April 1998 · Accepted: 21 September 1998  相似文献   

3.
A site in south-central Turkey has been proposed as the source for early bronze-age tin. Examination of the site shows that this proposal is confounded by the presence of extensive mining and smelting activities for lead. © 1994 John Wiley & Sons, Inc.  相似文献   

4.
A simple nomogram, which facilitates rapid time/cost estimates for archaeological and archaeometry surveys, is presented and discussed. © 1994 John Wiley & Sons, Inc.  相似文献   

5.
The European sturgeon (Acipenser sturio) is an endangered diadromous fish species that spawns in the rivers in late spring and early summer. The juveniles spend their first years in the brackish waters (5‰ to 25‰) of the estuary zone before moving out to sea. This study describes the downstream migration pattern of juvenile sturgeon, belonging to the 1994 cohort, the only one born naturally in the Gironde basin, France since the end of the 1980s. During October 1994 to December 1996 the inland section of the Gironde estuary was sampled monthly by trawl (n=818 tows) and all European sturgeon caught (n=381) were marked and released. The first sturgeon of the 1994 cohort (TL=27 cm) were caught in early March 1995 in the zones furthest upstream. During their second fall of life, juveniles gradually acclimatized, and spread over a wide range of salinity conditions. A first incursion into marine water was also observed (at least for a few fish) by the end of the second winter. During this second period, sturgeon showed preference for two particular zones situated at 18 and 38 km, respectively, from the mouth of the estuary. These zones, belonging to two different salinity sectors of the estuary, did not appear to be any different to their neighbors with regards to depth and type of substrate. There were no significant size differences among estuarine zones. Seasonal movements of sturgeon seem to be motivated by a search for warmer temperatures. After a period of early acclimatization of 15 months, juvenile European sturgeon appear to be highly tolerant of salinity variations.  相似文献   

6.
 The Ganga Plain is one of the most densely populated regions and one of the largest groundwater repositories of the Earth. For several decades, the drainage basin of the Ganga Plain has been used for the disposal of domestic and industrial wastes which has adversely affected the quality of water, sediments and agricultural soils of the plain. The concentrations of Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sn, Zn and organic carbon were determined in river sediments and soils of the Ganga Plain in the Kanpur-Unnao industrial region in 1994 and 1995 (pre-monsoon period of April–May). High contents (maximum values) of C-org (12.0 wt. %), Cr (3.40 wt. %), Sn (1.92 wt. %), Zn (4000 mg/kg), Pb (646 mg/kg), Cu (408 mg/kg), Ni (502 mg/kg) and Cd (9.8 mg/kg) in sediments (<20 μm fraction); and C-org (5.9 wt. %), Cr (2.16 wt. %), Sn (1.21 wt %), Zn (975 mg/kg) and Ni (482 mg/kg) in soils (<20 μm) in the pre-monsoon period of 1994 were found. From 1994 to 1995 the contents of Fe and Sn in sediments increase whereas those of C-org, Cd, Cu, Ni and Zn decrease. Considering the analytical errors, Al, Co, Cr, Mn and Pb do not show any change in their concentrations. In soils, the contents of Cd, Fe and Sn increase whereas those of Ni decrease from 1994 to 1995. Aluminium, Co, Cr, Cu, Mn, Pb and Zn do not show any change in their concentrations from 1994 to 1995. About 90% of the contents of Cd, Cr and Sn; 50–75% of C-org, Cu and Zn; and 25% of Co, Ni and Pb in sediments are derived from the anthropogenic input in relation to the natural background values, whereas in soils this is the case for about 90% of Cr and Sn; about 75% of Cd; and about 25% of C-org, Cu, Ni and Zn. The sediments of the study area show enrichment factors of 23.6 for Cr, 14.7 for Cd, 12.2 for Sn, 3.6 for C-org, 3.2 for Zn, 2.6 for Cu and 1.6 for Ni. The soils are enriched with factors of 10.7 for Cr, 9.0 for Sn, 3.6 for Cd, 1.8 for Ni and 1.5 for Cu and Zn, respectively. Received: 3 March 1998 · Accepted: 15 June 1998  相似文献   

7.
Kilauea East Rift Zone Magmatism: an Episode 54 Perspective   总被引:1,自引:0,他引:1  
On January 29–30, 1997, prolonged steady-state effusionof lava from Pu'u'O'o was briefly disrupted by shallow extensionbeneath Napau Crater, 1–4 km uprift of the active Kilaueavent. A 23-h-long eruption (episode 54) ensued from fissuresthat were overlapping or en echelon with eruptive fissures formedduring episode 1 in 1983 and those of earlier rift zone eruptionsin 1963 and 1968. Combined geophysical and petrologic data forthe 1994–1999 eruptive interval, including episode 54,reveal a variety of shallow magmatic conditions that persistin association with prolonged rift zone eruption. Near-ventlava samples document a significant range in composition, temperatureand crystallinity of pre-eruptive magma. As supported by phenocryst–liquidrelations and Kilauea mineral thermometers established herein,the rift zone extension that led to episode 54 resulted in mixtureof near-cotectic magma with discrete magma bodies cooled to  相似文献   

8.
 Shallow, anaerobic groundwater near a former manufactured-gas plant (MGP) in Charleston, South Carolina, USA, contains mono- and polycyclic aromatic hydrocarbons (MAHs and PAHs, respectively). Between 1994 and 1997, a combination of field, laboratory, and numerical-flow and transport-model investigations were made to assess natural attenuation processes affecting MAH and PAH distributions. This assessment included determination of adsorption coefficients (K ad ) and first-order biodegradation rate constants (K bio ) using aquifer material from the MGP site and adjacent properties. Naphthalene adsorption (K ad =1.35×10–7 m3/mg) to aquifer sediments was higher than toluene adsorption (K ad =9.34×10–10 m3/mg), suggesting preferential toluene transport relative to naphthalene. However, toluene and benzene distributions measured in January 1994 were smaller than the naphthalene distribution. This scenario can be explained, in part, by the differences between biodegradation rates of the compounds. Aerobic first-order rate constants of 14C-toluene, 14C-benzene, and 14C-naphthalene degradation were similar (–0.84, –0.03, and 0.88 day–1, respectively), but anaerobic rate constants were higher for toluene and benzene (–0.002 and –0.00014 day–1, respectively) than for naphthalene (–0.000046 day–1). Both areal and cross-sectional numerical simulations were used to test the hypothesis suggested by these rate differences that MAH compounds will be contained relative to PAHs. Predictive simulations indicated that the distributions of toluene and benzene reach steady-state conditions before groundwater flow lines discharge to an adjacent surface-water body, but do discharge low concentrations of naphthalene. Numerical predictions were "audited" by measuring concentrations of naphthalene, toluene, and benzene at the site in early 1997. Measured naphthalene and toluene concentrations were substantially reduced and the areal extent of contamination smaller than was both observed in January 1994 and predicted for 1997. Measured 1997 benzene concentrations and distribution were shown to be relatively unchanged from those measured in 1994, and similar to predictions for 1997. Received: 26 June 1997 · Accepted: 25 August 1997  相似文献   

9.
David Grigg 《GeoJournal》1998,44(1):9-18
A number of writers have argued that differences in food consumption between the countries in Europe are declining. This article investigates the possibility of convergence in the consumption of alcoholic beverages. The combination of beverages consumed in 1895–97, 1961–62 and 1994–95 is considered. This reveals three distinctive regions where wine, beer or spirits are the dominant drink. However, in this century the dominance of the staple drink has fallen and differences in total alcohol consumption have diminished, indicating convergence.  相似文献   

10.
 The South Canyon Fire of July 1994 burned 800 ha of vegetation on Storm King Mountain near Glenwood Springs, Colorado, USA. On the night of 1 September 1994, in response to torrential rains, debris flows inundated seven areas along a 5-km length of Interstate Highway 70. Mapping from aerial photographs, along with field observations and measurements, shows that the September rainstorm eroded unconsolidated, burned surficial soil from the hillsides, flushed dry-ravel deposits from the tributary channels, and transported loose, large material from the main channels. The hyperconcentrated flows and debris flows inundated 14 ha of Interstate Highway 70 with 70 000 m3 of material. Although the burned area was seeded in November 1994, the potential for continuing debris-flow activity remains. Incision and entrainment of channel alluvium, as well as erosion of loose material from the hillslopes could result in future debris- and hyperconcentrated-flow activity. Received: 15 October 1996 / Accepted: 25 June 1997  相似文献   

11.
 The McQuesten River system in central Yukon Territory, Canada, contains placer mines and reaches of sensitive fish habitat. Suspended sediment is supplied to the system by erosion of previously mined disturbed areas, bank erosion, resuspension of placer sediment deposited on bars, and active placer-mine discharges. Direct discharge from active placer mines did not have a large impact on suspended sediment in reaches of sensitive fish habitat in 1994–1995, although only two mines were active and concentrations did periodically exceed water quality objectives. Erosion of previously mined disturbed areas had a pronounced effect on suspended sediment during spring snowmelt and summer rainstorms in 1994–1995. Deposits in previously mined areas should be stabilized to reduce erosion and its downstream impact on fish habitat. Received: 10 November 1997 · Accepted: 30 March 1998  相似文献   

12.
Environmental and legal aspects of karst areas   总被引:3,自引:0,他引:3  
 Environmental impacts on karst settings are common as they are more sensitive than those of other rock terrains. Regulatory procedures that are effective in other rock terrains are not necessarily applicable to karst settings. Development and exploitation by man that affect the karst hydrology regime can trigger catastrophic events and result in numerous legal actions where the effects of changes go beyond property boundaries. A great variety of regulations and examples of litigation exist for karst areas. Received: 25 October 1994 · Accepted: 17 October 1995  相似文献   

13.
A catalog of maser spectra in the 1.35-cm water-vapor line towards the maser source NGC 2071 in a region of massive star formation is presented for 1994–2010. The observations were carried out using the 22-m antenna of the Pushchino Radio Astronomy Observatory with a spectral resolution of 0.101 km/s (0.0822 km/s after the end of 2005). Based on the data throughout the monitoring since 1980, two very different cycles of maser activity were found. The first (1980–1992) is characterized by high activity within a broad range of radial velocities. Emission at velocities near 7 km/s predominated in 1980–1986, and emission near 14–16 km/s, in 1987–1992. In 1997–2008, the maser intensity was appreciably lower than in the first activity cycle. Numerous flares of individual emission features were observed. Identifications based on VLA data show that strong flares took place in both maser sources, IRS1 and IRS3. Both sources demonstrated a low level of maser activity during essentially the same epochs (1977, 1995–1997, and the close of 2009 through the beginning of 2010), although the sources are separated by at least 2000 AU.  相似文献   

14.
The temple of Apollo in Delphi (Greece), built in 550 B.C., has been used to reconfirm a novel method of dating carved megalithic stone buildings using thermoluminescence (TL) (Liritzis, 1994). A calcitic (marble) sample was taken from the western side of the well-known inscribed polygonal wall, which constitutes the southern external support foundations of the temple. A partially bleached TL methodology was devised to determine first the ancient residual TL and then the correct archaeological dose. The obtained TL age of 420 ± 300 B.C. is compatible, within the margin of error, with the archaeological age. © 1997 John Wiley & Sons, Inc.  相似文献   

15.
We studied the macroinvertebrate fauna of a rocky shore in the freshwater tidal Hudson River during 1992–1994, the early years of the zebra mussel (Dreissena polymorpha) invasion. The macroinvertebrate community was numerically dominated by chironomids, nematodes, oligochaetes, gastropods, zebra mussels, and planarian flatworms. The community was a mixture of species typical of stony warm water rivers and lake shores, freshwater generalists, and semiterrestrial species. Overall macroinvertebrate densities were moderate to low (2,800–14,600 m−2). Density was a strong function of season and elevation, with consistently low densities in the early spring and in the intertidal zone. This pattern suggests that physical harshness (alternating submergence and desiccation;ice and low temperatures) limits the distribution of invertebrates at this site. Zebra mussels occurred at our study site chiefly below the low tide mark, but only at moderate abundance (usually <1,000 m−2). A weak correlation between the densities of zebra mussels and those of other macroinvertebrates nonetheless suggests that the zebra mussel invasion may have affected community structure.  相似文献   

16.
The Florida Bay ecosystem has changed substantially in the past decade, and alterations in the seagrass communities have been particularly conspicuous. In 1987 large areas ofThalassia testudinum (turtlegrass) began dying rapidly in western Florida Bay. Although the rate has slowed considerably, die-off continues in many parts of the bay. Since 1991, seagrasses in Florida Bay have been subjected to decreased light availability due to widespread, persistent microalgal blooms and resuspended sediments. In light of these recent impacts, we determined the current status of Florida Bay seagrass communities. During the summer of 1994, seagrass species composition, shoot density, shoot morphometrics, and standing crop were measured at 107 stations. Seagrasses had been quantified at these same stations 10 yr earlier by Zieman et al. (1989).T. testudinum was the most widespread and abundant seagrass species in Florida Bay in both 1984 and 1994, and turtlegrass distribution changed little over the decade. On a baywide basis,T. testudinum density and biomass declined significantly between surveys; mean short-shoot density ofT. testudinum dropped by 22% and standing crop by 28% over the decade.T. testudinum decline was not homogeneous throughout Florida Bay; largest reductions in shoot density and biomass were located principally in the central and western bay. Percent loss ofT. testudinum standing crop in western Florida Bay in 1994 was considerably greater at the stations with the highest levels of standing crop in 1984 (126–215 g dry wt m−2) than at the stations with lower levels of biomass. While turtlegrass distribution remained consistent over time, both the distribution and abundance of two other seagrasses,Halodule wrightii andSyringodium filiforme, declined substantially between 1984 and 1994. Baywide,H. wrightii shoot density and standing crop declined by 92%, andS. filiforme density and standing crop declined by 93% and 88%, respectively, between surveys. Patterns of seagrass loss in Florida Bay between 1984 and 1994 suggest die-off and chronic light reductions were the most likely causes for decline. If die-off and persistent water-column turbidity continue in Florida Bay, the long-term future of seagrasses in the bay is uncertain.  相似文献   

17.
《Applied Geochemistry》1998,13(7):841-850
Increasing fumarolic activity at Popocatépetl volcano has been observed since 1992. On 21 December 1994, a series of eruptions at Popocatépetl volcano produced ash emissions that reached the city of Puebla located to the east of the volcano. Eruptive activity declined sharply from June 1995 until 5 March 1996 when ash emissions and fumarole flux increased to levels similar to those of December, 1994. Intermittent ash production has continued to 1997. Ash was sampled at more than 80 different locations around the volcano during the various eruptions. Gas produced during an eruption may be scavenged by the ash and leaching of the ash with water allows determination of the concentration of ions adsorbed from the volcanic gases. The leachates obtained from eruptions from December 1994 until 28 November 1996, were analyzed by potentiometry with selective electrodes for Cl and F and by ion chromatography for SO42−. Minor cations (Co2+, Pb2+, Zn2+, Cu2+, Mn2+, Sb2+, Ti4+, Cd2+, Tl3+) were determined in some samples by ICP-MS. The highest concentrations of Cl and SO42− were obtained for the 21 December 1994 ash at the start of the eruptions with 19 550 ppm SO42− and 1028 ppm Cl and for the emission which occurred on 5 March 1996, with 21 775 ppm SO42− and 1250 ppm Cl. At both times a concentration decrease was observed, but with particular trends in each case. The composition of the ash leachates suggests that the two Popocatépetl eruptions in 1994 and 1996 began with phreatic and magmatic components. The increase in F and the decrease in the Cl/F ratio may indicate a heating up of the volcanic system at the beginning of March, 1996, one week before the outpouring of lava in the bottom of the crater on 20 March 1996. The concentration trends for SO42−, Cl and F suggest that during the 1996 activity, the system attained higher temperatures than in 1994–1995.  相似文献   

18.
《GeoJournal》1994,34(3):314-314
Richard F. Logan, 1914–1994  相似文献   

19.
Peatlands are an important multipurpose ecosystem, supporting huge quantities of biomass and peat soil carbon. A time series of Japanese Earth Resource Satellite-1 (JERS-1) L-band Synthetic Aperture Radar (SAR) data was employed to monitor two dynamic ecosystem processes; deforestation and inundation patterns. Using a change detection analysis for three images acquired during dry seasons of 1994, 1997 and 1998, we detected the deforestation that has occurred in the region due to the anthropogenic and natural causes. At a threshold of ±2 dB change in backscattering response, an area of about 98 km2 of these forests was found to have been cleared during 1994–1997 for conversion to cultivatable lands. However, the agricultural crops miserably failed to grow on these cleared lands because of the adverse water and soil chemistry conditions. The deliberate draining of these lands, by laying and extension of a huge network of canals, created congenial ecological conditions for the spread of forest fires, particularly during the 1997 El Niño period. An area of 250 km2 of forests was thus detected to have been destroyed by these fires between September 1997 and January 1998. These deforested lands are rapidly regenerating since their abandonment and the regenerating carbon stocks were simulated using the CENTURY ecosystem dynamics model. Furthermore, the L-band SAR was able to detect the pixel-wise seasonal and spatial inundation information for particular forest types where the transmissivity of the L-band SAR signals was quite significant. These forest types corresponded to comparatively low biomass areas. The SAR derived information about these two important dynamic processes would be useful for improving the accuracy of modelling the spatial and temporal distribution of the carbon and other trace gases in these ecosystems.Edited by D. Boyd  相似文献   

20.
Coves near an ocean inlet in Little Egg Harbor in southern New Jersey may be important settlement areas for winter flounder (Pseudopleuronectes americanus), based on the high abundance of small postlarval individuals. During 1994–1996 we sampled in two coves and adjacent areas of this same estuary to determine if this pattern was annually consistent. Collections in spring and early summer indicated that small, recently-settled winter flounder (10–45 mm TL) were abundant in the coves from May to mid-June in every year with maximum mean densities ranging from 1.5–2.5 ind m−2 and that these same size individuals were never collected at these densities in other habitats in the same estuary. Densities in the coves declined soon after settlement, usually by late June to early July in each year. In order to determine factors that may influence these high settlement rates we examined aspects of habitat quality by determining habitat-specific growth rates in cages for recently-settled individuals (17.5–38.3 mm TL) both inside and outside the coves during 1995. These rates (3.7–9.1 wt d−1) overlapped those of other estuarine habitats (3.1–10.5 wt d−1) suggesting that habitat quality, based on growth, does not differentiate the coves from other potential settlement habitats. Mark/recapture experiments for recently settled individuals (range 13–70 mm TL) in 1994 and 1996 had low recapture rates (1% in both years) suggesting that dispersal from the cove occurred soon after settlement. This pattern confirms that these coves are used as settlement areas but they are probably not used as nurseries because winter flounder, at least in this system, do not settle and stay and, as a result, use other habitats as primary nursery areas.  相似文献   

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