New Zealand since 1984: Elite succession, income distribution and economic growth in a small trading economy     

Geoff Bertram 《GeoJournal》2004,59(2):93-106

Four interrelated patterns of structural change in the New Zealand economy since 1980 are identified and analysed, against the backdrop of a growth rate which fell substantially behind the rest of the OECD in the late 1980s and early 1990s before recovering, but without catchup, from 1993. The changes discussed are: a shift in sharemarket capitalization from formerly-dominant productive activities in agriculture, manufacturing and construction to the current predominance of utilities, transport and finance; a sharp increase in overseas investors' share of the economic surplus, from around 20% to over half of post-tax corporate profits; a steady rise in international indebtedness at the same time as sovereign foreign-currency debt was eliminated; hence overseas debt was successfully privatized; a weakening of regulatory control over monopoly profits, opening the way for a surge of rent-seeking activity during the 1990s. The neoliberal reform programme has achieved fiscal and monetary sustainability, increased market flexibility, and insulated the economy against external shocks. At the same time it has led to denationalisation of economic surplus, ongoing current account deficits, and a significant diversion of resources from productive use into rent-seeking. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Stress Distribution in the Upper Shihezi Formation from 1D Mechanical Earth Model and 3D Heterogeneous Geomechanical Model,Linxing Region,Eastern Ordos Basin,Central China     

JU Wei  SHEN Jian  QIN Yong  WANG Geoff  XU Ke  LI Guozhang  LI Chao 《《地质学报》英文版》2021,95(3):976-987

The Upper Shihezi sedimentary rocks in the Linxing region has been estimated with a significant volume of tight sandstone gas.However,lateral distribution of the present-day stress magnitude is poorly understood,which limits further gas production.Hence,a one-dimensional mechanical earth model and a three-dimensional heterogeneous geomechanical model are built to address this issue.The results indicate that the strike-slip stress regime is dominant in the Upper Shihezi Formation.Relatively low stresses are mainly located around wells L-60,L-22,L-40,L-90,etc,and stress distributions exhibit the similarity in the Members H2 and H4.The differential stresses are relatively low in the Upper Shihezi Formation,suggesting that complex hydraulic fracture networks may be produced.Natural fractures in the Upper Shihezi Formation contribute little to the overall gas production in the Linxing region.In addition,the minimum principal stress gradient increases with Young’s modulus,suggesting that the stiffer rocks commonly convey higher stress magnitudes.There is a strong interplay between stress distribution and heterogeneity in rock mechanics.Overall,the relative error between the predicted and measured results is less than 10%,implying that the predicted stress distribution is reliable and can be used for subsequent analysis in the Linxing region.  相似文献   

Forecast of Low Visibility and Fog from NCEP: Current Status and Efforts   总被引：2，自引：0，他引：2  

Binbin Zhou  Jun Du  Ismail Gultepe  Geoff Dimego 《Pure and Applied Geophysics》2012,169(5-6):895-909

Based on the visibility analysis data during November 2009 through April 2010 over North America from the Aviation Digital Database Service (ADDS), the performance of low visibility/fog predictions from the current operational 12?km-NAM, 13?km-RUC and 32?km-WRF-NMM models at the National Centers for Environmental Prediction (NCEP) was evaluated. The evaluation shows that the performance of the low visibility/fog forecasts from these models is still poor in comparison to those of precipitation forecasts from the same models. In order to improve the skill of the low visibility/fog prediction, three efforts have been made at NCEP, including application of a rule-based fog detection scheme, extension of the NCEP Short Range Ensemble Forecast System (SREF) to fog ensemble probabilistic forecasts, and a combination of these two applications. How to apply these techniques in fog prediction is described and evaluated with the same visibility analysis data over the same period of time. The evaluation results demonstrate that using the multi-rule-based fog detection scheme significantly improves the fog forecast skill for all three models relative to visibility-diagnosed fog prediction, and with a combination of both rule-based fog detection and the ensemble technique, the performance skill of fog forecasting can be further raised.  相似文献   

Estimation of tephra volumes from sparse and incompletely observed deposit thicknesses   总被引：1，自引：0，他引：1  

Rebecca M. Green  Mark S. Bebbington  Geoff Jones  Shane J. Cronin  Michael B. Turner 《Bulletin of Volcanology》2016,78(4):25

We present a Bayesian statistical approach to estimate volumes for a series of eruptions from an assemblage of sparse proximal and distal tephra (volcanic ash) deposits. Most volume estimates are of widespread tephra deposits from large events using isopach maps constructed from observations at exposed locations. Instead, we incorporate raw thickness measurements, focussing on tephra thickness data from cores extracted from lake sediments and through swamp deposits. This facilitates investigation into the dispersal pattern and volume of tephra from much smaller eruption events. Given the general scarcity of data and the physical phenomena governing tephra thickness attenuation, a hybrid Bayesian-empirical tephra attenuation model is required. Point thickness observations are modeled as a function of the distance and angular direction of each location. The dispersal of tephra from larger well-estimated eruptions are used as leverage for understanding the smaller unknown events, and uncertainty in thickness measurements can be properly accounted for. The model estimates the wind and site-specific effects on the tephra deposits in addition to volumes. Our technique is exemplified on a series of tephra deposits from Mt Taranaki (New Zealand). The resulting estimates provide a comprehensive record suitable for supporting hazard models. Posterior mean volume estimates range from 0.02 to 0.26 km ³. Preliminary examination of the results suggests a size-predictable relationship.  相似文献   

Numerical simulation on tendency mining fracture evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth     

Qing Ye  Wei-jun Wang  Geoff Wang  Zhen-zhen Jia 《Arabian Journal of Geosciences》2017,10(4):82

In order to master the tendency mining-fracture-evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth in mining process, the 1221 working face in Zhao mine is selected as the engineering background and a mathematical model is established. The displacement variation, stress and strain of overlying strata and coal seams are simulated by using ANSYS software. In the mining process, the movement characteristics, displacement variation laws and fracture evolution characteristics of overlying strata and coal seams above working face with large inclination angle and mining depth along inclination direction are discussed. Simulation results show that with the advance of working face, the fracture development of overlying strata and coal seams is larger and larger; the area of gob is gradually expanding and the transverse stress of overlying strata and coal seams is also expanding. Stress contour of overlying strata and coal seams at both ends of gob becomes denser and denser; the activity of the overlying strata and coal seams near the up-roadway side of the gob is violent. The pressure relief zone is formed in the upper part of the strata and the roof above the gob. Large inclination angle of coal seam results in larger supporting pressure in the underside of the gob and smaller supporting pressure in the upper side of the gob. Along the inclination direction of the working face, the pressure relief zone is mainly concentrated in the outlet roadway of the working face; the fracture development and strata separation are obvious, which offer good passage for gas flow and migration.  相似文献   

Assessing the impact of land use change on hydrology by ensemble modeling (LUCHEM). I: Model intercomparison with current land use     

L. Breuer  J.A. Huisman  P. Willems  H. Bormann  A. Bronstert  B.F.W. Croke  H.-G. Frede  T. Gräff  L. Hubrechts  A.J. Jakeman  G. Kite  J. Lanini  G. Leavesley  D.P. Lettenmaier  G. Lindström  J. Seibert  M. Sivapalan  N.R. Viney 《Advances in water resources》2009

This paper introduces the project on ‘Assessing the impact of land use change on hydrology by ensemble modeling (LUCHEM)’ that aims at investigating the envelope of predictions on changes in hydrological fluxes due to land use change. As part of a series of four papers, this paper outlines the motivation and setup of LUCHEM, and presents a model intercomparison for the present-day simulation results. Such an intercomparison provides a valuable basis to investigate the effects of different model structures on model predictions and paves the ground for the analysis of the performance of multi-model ensembles and the reliability of the scenario predictions in companion papers. In this study, we applied a set of 10 lumped, semi-lumped and fully distributed hydrological models that have been previously used in land use change studies to the low mountainous Dill catchment, Germany. Substantial differences in model performance were observed with Nash–Sutcliffe efficiencies ranging from 0.53 to 0.92. Differences in model performance were attributed to (1) model input data, (2) model calibration and (3) the physical basis of the models. The models were applied with two sets of input data: an original and a homogenized data set. This homogenization of precipitation, temperature and leaf area index was performed to reduce the variation between the models. Homogenization improved the comparability of model simulations and resulted in a reduced average bias, although some variation in model data input remained. The effect of the physical differences between models on the long-term water balance was mainly attributed to differences in how models represent evapotranspiration. Semi-lumped and lumped conceptual models slightly outperformed the fully distributed and physically based models. This was attributed to the automatic model calibration typically used for this type of models. Overall, however, we conclude that there was no superior model if several measures of model performance are considered and that all models are suitable to participate in further multi-model ensemble set-ups and land use change scenario investigations.  相似文献   

The glutathione antioxidant system as a biomarker suite for the assessment of heavy metal exposure and effect in the grey mangrove, Avicennia marina (Forsk.) Vierh   总被引：1，自引：0，他引：1  

Caregnato FF  Koller CE  MacFarlane GR  Moreira JC 《Marine pollution bulletin》2008,56(6):1119-1127

Alterations in the glutathione antioxidant system and lipid peroxidation in Avicennia marina were studied under laboratory and field conditions. The activity of glutathione peroxidase (GPx) was found to respond to Zn exposure, and a significant positive relationship between leaf Zn concentration and GPx activity was observed after 96 h and 8 weeks. Lipid hydroperoxides increased proportionally with increasing leaf Zn concentration after 2 and 8 weeks, while no changes in total glutathione were observed. Induction of GPx at 96 h predicted effects at the individual level at a later time interval (reduced biomass at 8 weeks). Results from the field revealed that increasing leaf metal concentration (Zn, Cu or Pb) produced a proportional increase in GPx activity whereas lipid hydroperoxides and total glutathione were not affected. The utility of GPx as an early warning biomarker is suggested, since GPx activity increases in a dose-dependant fashion in response to accumulated leaf metals, and is predictive of later effects on growth.  相似文献   

Peripheral gully and landslide erosion on an extreme anthropogenic landscape produced by mountaintop removal coal mining     

Miles Reed  Steve Kite 《地球表面变化过程与地形》2020,45(9):2078-2090

Mountaintop removal/valley fill coal mining (MTR/VF) in central Appalachia has buried an estimated 4000 km of headwater streams, but the long-term geomorphic consequences of the anthropogenic valley fills and associated mined landscapes are poorly understood. These anthropogenic landscapes are not intended to be maintained in perpetuity once reclamation is complete. Here we present the first ever field-based study of erosional landforms on this type of mined landscape paired with the subsequent examination of 10 regional LiDAR (light detection and ranging) datasets for gullies and landslides in a transect from eastern Kentucky to central West Virginia. Field observations indicate that overtopping of or intentional discharge from drainage systems and overtopping of valley fill terraces can initiate gullying. We manually extracted 1328 gullies from 512 km² of mined landscape within the LiDAR datasets. Gullies are predominantly located along the perimeter of the mined landscape with the majority of gullies associated with drainage systems. The number of gullies linearly scales with mined area (R² = 0.66). We observed 387 landslides along the perimeter of MTR/VF. Within the datasets, landslides per km² ranged from 0.1 to 3.9. We observed 34 landslides within fully reclaimed valley fills, a heretofore undocumented phenomenon. Over 90% of these landslides were in Kentucky datasets, which covered only 47% of total mined area analyzed. Previously measured regional differences in the angle of friction of mine spoils or construction practices may explain the abundance of gullies and elevated level of landslide occurrence in eastern Kentucky valley fills relative to West Virginia. Observations of erosion on regionally extensive MTR/VF landscapes warrant further study to better ascertain ecological impacts. Large-scale alteration by surface mining in steep landscapes may generally lead to peripheral gully erosion. © 2020 John Wiley & Sons, Ltd.  相似文献   

The spatiality of multifunctional agriculture: A human geography perspective   总被引：8，自引：0，他引：8  

Geoff A. Wilson 《Geoforum》2009,40(2):269-280

Based on reconceptualisations of multifunctional agriculture as a normative spectrum of decision-making (strong to weak multifunctionality) bounded by productivist and non-productivist action and thought [Hollander, G.M., 2004. Agricultural trade liberalization, multifunctionality, and sugar in the south Florida landscape. Geoforum 35, 299-312; Holmes, J., 2006. Impulses towards a multifunctional transition in rural Australia: gaps in the research agenda. Journal of Rural Studies 22, 142-160; Wilson, G.A., 2007. Multifunctional Agriculture: A Transition Theory Perspective. CAB International, Wallingford], this paper argues that there is currently insufficient research into the geography of multifunctionality. Building on current human geography debates about issues of scale, the paper suggests that we should conceive of multifunctionality as a spatially complex nested hierarchy comprising different interlinked ’layers’ of multifunctional decision-making ranging from the farm level to the national and global levels. It suggests that the notion of multifunctional agriculture only makes sense if it is applied at the farm level as the most important spatial scale for the implementation of multifunctional action ‘on the ground’. Multifunctionality can be interpreted as having ’direct’ expression only at the ’lower’ geographical scales (i.e. farm, community and regional levels in particular) while the regional, national and global levels show ’indirect’ expressions of multifunctionality that are mediated by local level actors in order to find tangible expression on the ground. The notion of global-level multifunctionality is the most challenging, as this level lacks political and ideological coherence about the required directions necessary for implementation of strong multifunctionality pathways. The paper concludes by arguing that much work still awaits those investigating the spatiality of multifunctionality, in particular with regard to the question whether global-level strong multifunctionality is possible, or whether strong multifunctionality in one territory is predicated on weak multifunctionality in others.  相似文献   

Perfluorinated alkyl acids in water, sediment and wildlife from Sydney Harbour and surroundings     

Thompson J  Roach A  Eaglesham G  Bartkow ME  Edge K  Mueller JF 《Marine pollution bulletin》2011,62(12):2869-2875

Perfluorinated alkyl compounds (PFCs) including perfluorooctane sulphonate (PFOS) and perfluorooctanoate (PFOA) were measured in environmental samples collected from around Homebush Bay, an urban/industrial area in the upper reaches of Sydney Harbour and Parramatta River estuary. Water, surface sediment, Sea Mullet (Mugil cephalus), Sydney Rock Oyster (Saccostrea commercialis) and eggs of two bird species; White Ibis (Threskiornis molucca), and Silver Gull (Larus novaehollandiae) were analysed. In most samples PFOS was the dominant PFC. Geometric mean PFOS concentrations were 33 ng/g ww (wet weight) in gull eggs, 34 ng/g ww in ibis eggs, and 1.8 ng/g ww and 66 ng/g ww in Sea Mullet muscle and liver, respectively. In sediment the PFOS geometric mean was 1.5 ng/g, in water average PFOS and PFOA concentrations ranged from 7.5 to 21 ng/L and 4.2 to 6.4 ng/L, respectively. In oysters perfluorododecanoic acid was most abundant, with a geometric mean of 2.5 ng/g ww.  相似文献