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91.
92.
Geo-information tools for participatory spatial planning: Fulfilling the criteria for ‘good’ governance? 总被引:2,自引:0,他引:2
The last few decades have seen increasing attempts to foster ‘collaborative’ and ‘participatory’ approaches to spatial planning and decision-making, with a more sophisticated conceptualisation of the contested term, participation. Participatory, ‘bottom-up’ geo-information technologies have been concurrently developing and these are expected to strengthen participatory spatial planning; important among these has been the transformation of conventional mapping and GIS tools into Participatory GIS (PGIS). In this paper we explore the potential contributions of participatory geo-information tools towards participatory spatial planning, in terms of the principles and criteria of good governance. We discuss five fundamental principles of ‘good’ governance: accountability, legitimacy, respect, equity, and competence, and the potential of geo-information tools to contribute to, and detract from, such principles; although we focus especially on participation and the recognition and validation of local knowledge. We derive criteria for the five principles, and we identify a range of evaluation questions which can be operationalised so as to interrogate the criteria for judging the contribution of participatory tools and participatory spatial planning activities. We conclude by summarily assessing the potentials of participatory geo-information tools, particularly participatory mobile GIS, participatory 3-dimensional modelling, and visualisation features in PGIS. 相似文献
93.
Todd Dunn 《Contributions to Mineralogy and Petrology》1987,96(4):476-484
The crystal/liquid partition coefficients of Lu, Hf, Ti, Mn and Ca have been measured between olivine, clinopyroxene and basaltic melt. The Ti, Mn, and Ca partition coefficients were determined at natural abundance levels. The Lu and Hf partition coefficients were determined at doping levels ranging from 0.5 to 1.5 wt% “trace element” as oxide in order to allow analysis by electron microprobe. Olivine/liquid partition coefficients for Lu, Hf, Ti, Mn, and Ca were determined at 1 bar and temperatures from 1150 to 1177° C. Clinopyroxene/liquid partition coefficients were determined for Lu, Hf, Ti, and Mn at pressures of 10, 15, and 20 kbars and temperatures from 1250 to 1290° C. The olivine/liquid partition coefficients of Hf, Lu, Ti, and Ca are small. D(Hf-ol) is zero within the analytical uncertainty. Both D(Lu-ol) and D(Mn-ol) decrease with increasing temperature, but D(Ti-ol) and D(Ca-ol) are constant over the narrow temperature range studied. The partition coefficient results are summarized below.
T°C 相似文献
94.
Foliage from Douglas-fir (Pseudotsuga menziesii) tops was collected from 94 sites around the poorly exposed QR Au deposit in central British Columbia. Locally high concentrations of gold in ashed stems suggest a northwestward (down-ice) dispersion train of Au extending uphill for at least 500 m from the deposit. In addition, a down-slope, hydromorphic dispersion train is evident. All trees sampled are extremely rich in As, but the patterns of As distribution are less clearly related to the mineralization than those of Au enrichment. Summary statistics of analytical data for 35 elements are provided to serve as baseline information for any future studies.The sampling method, which is described in detail, is simple and cost-effective. In one hour the foliage of tree tops from about 50 sites, spaced at intervals of 200 m or more, can be collected by a three-person helicopter crew. The technique is particularly appropriate for rapidly screening rugged or heavily forested terrain, regardless of snow-cover, in order to establish priorities for ground follow-up exploration targets. 相似文献
95.
This paper presents an analysis of a neglected area of study by geographers; that of resident action groups. During the 1980s there has been a significant increase in the number of resident action groups throughout Sydney. Resident activism has influenced local planning processes, the location of noxious facilities and subsequent urban form. This has initiated important reactions by government at both the local and State levels. Urban collective activisms have been hypothesised as single‐issue, self‐serving nimby groups. However, RAGs are also empowering forces, in which women and men are introduced to the political structures and become engaged in protest and resistance that can challenge the social and spatial order. RAGs can, either singularly or cumulatively, force a re‐aligning of existing power relations, and they can necessitate changed modes of governance (or govern‐mentality). 相似文献
96.
High‐frequency sampling of stable water isotopes in precipitation and stream water during winter and summer storm events was carried out in a 2·3 km2 lowland agricultural catchment. During peak flows of monitored events, the responses of δ2H and δ18O were comparable and inferred the dominance (ca 70%) of ‘old’ pre‐event water. Transit Time Distribution (TTD) inferred by a gamma function were fitted (Nash–Sutcliffe = 0·8) and were also similar for δ2H and δ18O. However, the shape (α) and scaling (β) parameters were markedly different for summer and winter events. Consequently, when antecedent wetness was high, mean transit times were in the order of days; when drier, they increased to months. Moreover, while the responses of δ2H and δ18O exhibited similar gradual recovery to pre‐event conditions during winter hydrograph recessions, they differed dramatically on summer recessions. Time series analysis showed that δ2H isotope content was correlated with the diurnal cycle of air temperature, suggesting an evaporative fractionation pattern which could be reproduced by a temperature‐based first‐order autoregressive model. The heavier δ18O isotope showed no evidence for such diurnal variability. The study highlights the utility of high‐frequency stable isotope sampling to explore the time‐variant nature of TTDs. Furthermore, it shows that the time of sampling in a diurnal cycle may have crucial significance for interpreting stream isotope signatures, particularly δ2H. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
97.
Zusammenfassung Die Kristallstruktur des Stranskiits wurde mit neuen Meßdaten, die an einer aus Tsumeb stammenden Probe gewonnen worden waren, bis zuR=0,034 für 1239 unabhängige beobachtete Reflexe verfeinert. Von der verfeinerten Struktur wurde die Ladungsbilanz aufgestellt und besonders im Hinblick auf die Ladungsdeformation des Cu2+ diskutiert. Eine Mikrosondenanalyse derselben Probe ergab, daß die tatsächliche Zusammensetzung der angegebenen Formel entspricht.
Charge balance of a refined crystal structure of stranskiite, Zn2Cu (AsO4)2 Summary The crystal structure of stranskiite was refined with new intensity data obtained from a specimen from Tsumeb toR=0.034 for 1234 observed independent reflections. The charge balance was calculated and discussed particularly with respect of the charge deformation of Cu2+. An electron probe microanalysis gave the result that the actual composition of the specimen corresponds to the given formula.相似文献 98.
99.
Sean S. Lindsay Tasha L. Dunn Joshua P. Emery Neil E. Bowles 《Meteoritics & planetary science》2016,51(4):806-817
Near‐infrared reflectance spectra of S‐type asteroids contain two absorptions at 1 and 2 μm (band I and II) that are diagnostic of mineralogy. A parameterization of these two bands is frequently employed to determine the mineralogy of S(IV) asteroids through the use of ordinary chondrite calibration equations that link the mineralogy to band parameters. The most widely used calibration study uses a Band II terminal wavelength point (red edge) at 2.50 μm. However, due to the limitations of the NIR detectors on prominent telescopes used in asteroid research, spectral data for asteroids are typically only reliable out to 2.45 μm. We refer to this discrepancy as “The Red Edge Problem.” In this report, we evaluate the associated errors for measured band area ratios (BAR = Area BII/BI) and calculated relative abundance measurements. We find that the Red Edge Problem is often not the dominant source of error for the observationally limited red edge set at 2.45 μm, but it frequently is for a red edge set at 2.40 μm. The error, however, is one sided and therefore systematic. As such, we provide equations to adjust measured BARs to values with a different red edge definition. We also provide new ol/(ol+px) calibration equations for red edges set at 2.40 and 2.45 μm. 相似文献
100.
S. M. Dunn J. R. Bacon C. Soulsby D. Tetzlaff M. I. Stutter S. Waldron I. A. Malcolm 《水文研究》2008,22(24):4767-4782
The isotope hydrology of a set of nested sub-catchments in the north-east of Scotland has been studied to examine the mixing processes and residence times of water in the catchments. The measured δ18O in stream waters was found to be exceptionally uniform both temporally and spatially. Hydrochemical mixing analyses showed that groundwater contributes between 62 and 90% of the stream flow in all sub-catchments. Model analysis indicated that the δ18O in stream water is indicative of a highly mixed system in which near surface runoff appears to be mixed with groundwater, within the soil profile, before being released from the catchment. Small fluctuations in the stream water δ18O response are generated by a small proportion (<10%) of less-well mixed water in infiltration excess runoff during storm events. A comparative application of the model to a nearby catchment, which has a lower proportion of groundwater runoff, demonstrated contrasting behaviour, with significantly less mixing of waters occurring and a more distinct difference in the age of runoff generated by different flow paths. This highlighted that standard methods for characterization of mixing mechanisms are often insufficient and may not discriminate between systems that have retained quite distinct flow paths throughout catchment transit, and those which have been mixed at some stage. Model sensitivity analysis also indicated that the simulated mean residence time of water varies most strongly in response to different parameters compared with the δ18O response. This has implications for estimating water residence times from isotope data. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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