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2.
Albert A. Bartlett 《Natural Resources Research》2006,15(3):151-164
This paper examines the implications of statements by Australia’s Minister of… Resources that Australia’s exports of coal
are growing rapidly and that Australia’s coal will last “110 years at current rates of production.” If one assumes that coal
production P(t), follows a Gaussian curve (similar to a Hubbert curve) one can construct a family of Gaussian curves showing possible future
paths of P(t) which are consistent with the cited “110 years.” Each curve reaches a maximum after which P(t) declines toward zero. Knowledge of the present value of dP/dt allows one member of the family to be identified as the most probable future path of P(t). Families of curves and tabular data are presented for resource quantities that would last 50, 100 and 200 years “at current
rates of production.” If, instead, Australia’s P(t) follows a declining exponential curve (exp(−kt)) with k = (1/110) per year, the stated quantity of coal will allow production to continue forever, with P(t) declining with a half life of 76 y. This and more rapidly declining exponential paths are the only paths that can be said
to be sustainable. The envelope of the family of Gaussian curves divides the (P, t) plane into “allowed” and “forbidden” areas.
The declining exponential curve divides the “allowed” area into an upper area that is “terminal” and a lower area that is
“sustainable.” These facts, coupled with Australia’s expectations of rapid growth of its population, suggest that Australia’s
present resource policies are “anti-sustainable” and that the people of Australia need to rethink their present policy of
rapidly exporting their fossil fuels. 相似文献
3.
Stimulated by the exceeding progress of information technology, the development of mineral exploration has entered a new period of digitization and quantification. The “three components” approach of mineral prediction is suggested as a new approach to the “digital mineral prospecting,” which is based on the geoanomaly analysis, directed by the research on the diversity of mineralization and on the spectrum of mineral deposits. Close combination of these three aspects of quantitative study makes a new starting point to the digital prospecting. In this paper, the basic theories of the “three components” approach of mineral prediction are discussed. In addition, based on the new achievements in the studies on the prediction and assessment of solid minerals and gas–oil resources, we have centered our discussion on the thought of analysis of geoanomaly evolution and on the “5P” method for approaching the target area in the “three components” approach of mineral prediction. 相似文献
4.
土地利用变化时空模型的图谱方法--以黄河三角洲为例 总被引：12，自引：0，他引：12
Changesinlandcoverandland-usehaveimpactsandimplicationsatlocal,regionalandglobalscalesbecauseofthewaytheyalterbiophysical,biogeochemicalandhydrologicalstatesandprocesses(Alcamoetal.,1996;Li,1996).Since1990,scientistsathomeandabroadhavebeenpayingattentiontoresearchesonland-useandland-coverchange(LUCC)(Turneretal.,1990;MeyerandTurner,1994),butresearchisnotenoughon"spaceandprocess"ofLUCC(Turneretal.,1995).Spatialrelationshipbetweenvariablesyethasnotbeenestablished(Bockstael,1996).Soitispara… 相似文献
5.
社会生态补偿标准测算方法(英文) 总被引：2，自引：0，他引：2
Ecological compensation is a hot subject in academic studies, and the determina-tion of the spatial allocation of compensation payments is a key point in the research of eco-logical compensation. There are two kinds of thoughts in the determination of regional spatial allocation at present: "evaluation of ecological construction cost" and "evaluation of ecosystem services value". This paper analyzes the relationships between social ecological compensation and regional socio-economic development, and establishes two econometric models with the data of 2007 from various provinces in China. Through these models, the impacts of geographical endowments on the regional socio-economic development in various provinces are analyzed from the social justice viewpoint and the concept of "equivalent value of geographical endowments" (EGE for short) is proposed. This paper analyzes the application prospect of EGE in the policy making of regional ecological compensation. The results showed that: (1) the implementation of social ecological compensation is not only an effective guarantee for each region to obtain the equal rights of survival, development and decent environment, but also an essential assurance to the coordinated, balanced and sustainable development among various regions; (2) the regional difference in geographical endowments is an important factor affecting the regional spatial variation of socio-economic development. Therefore, geographical endowments are important bases for the determination of the spatial allocation of compensation payments in social ecological compensation; (3) based on the EGE, the government can determine the spatial allocation of social ecological compensation scientifically, and avoid the "sweeping approach" phenomenon in the policy making process of ecological compensation. 相似文献
6.
WANG Xiqin ZHANG Yuan LIU Changming 《地理学报(英文版)》2007,17(3):304-316
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that： except Xiliao River is ＂median＂, the rest are all upon ＂good＂, the Dongliao River is even ＂very good＂. The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that： considering ＂quantity＂, except Xiliao River, the rest rivers can all achieve the ＂quantity＂ criteria of the en- vironmental flows of river requirements, but if considering the aspect of ＂quality＂, only Dongliao River can reach the ＂quality＂ standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands. 相似文献
7.
Amalgamation of a number of continental fragments during the Late Neoproterozoic resulted in a united Gondwana continent.
The time period in question, at the end of the Precambrian, spans about 250 million years between ∼800 and 550 Ma. Geological
activity focused along orogenic belts in Africa during that time period is generally referred to as “Pan African.” We identify
three age-related classes of tectonic terranes within these orogenic belts, differentiated on the basis of the formation-age
of their crust: juvenile (e.g. mantle derived at or near the time of the orogenesis, ∼0.5–0.8 Ga), Paleoproterozoic (∼1.8–2.5 Ga),
Archean (>2.5 Ga). We combine African mineral deposits data of these terranes on a new Neoproterozoic tectonic map of Africa.
The spatial correlation between geological terranes in the belts and mineral occurrences are determined in order to define
the metallogenic character of each terrane, which we refer to as their “metallogenic fingerprint.” We use these fingerprints
to evaluate the effectiveness of mobilization (“recycling”) of mineral deposits within old crustal fragments during Pan African
orogenesis. This analysis involves normalization factors derived from the average metallogenic fingerprints of pristine older
crust (e.g. Palaeoproterozoic shields and Archean cratons not affected by Pan African orogenesis) and of juvenile Pan African
crust (e.g. the Nubian Shield). We find that mineral deposit patterns are distinctly different in older crust that has been
remobilized in the Pan African belts compared to those in juvenile crust of Neoproterozoic age, and that the concentration
of deposits in remobilized older crust is in all cases significantly depleted relative to that in their pristine age-equivalents.
Lower crustal sections (granulite domains) within the Pan African belts are also strongly depleted in mineral deposits relative
to the upper crustal sections of juvenile Neoproterozoic terranes. A depletion factor for all terranes in Pan African orogens
is derived with which to evaluate the role of mineral deposit recycling during orogenesis. We conclude that recycling of old
mineral deposits in younger orogenic belts contributes, on average, to secular decrease of the total mineral endowment of
continental crust. This could be of value when formulating exploration strategies. 相似文献
8.
E. D. Attanasi 《Natural Resources Research》1998,7(4):271-279
According to the National Research Council’s Committee on Earth Resources the stated goal of the “sustainability” paradigm
is that the economic activity that maintains current well-being not make future generations worse off, either through environmental
degradation or resource depletion. Coal is not “running out” in the United States but the effects of economic deregulation
of electricity generation, new air quality standards (Phase II of the 1990 Clear Air Act Amendments), and continued restructuring
of the coal mining industry will likely stretch lowsulfur coal supplies in the next decade. The paper discusses these forces
and then presents summary coal quality data in the form of grade-cumulative tonnage relationships for major U.S. producing
areas to show where future low-sulfur coal supplies are likely to come from. The final section considers the potential magnitude
of additional demand for low-sulfur coal, alternative compliance strategies, and implications in terms of maintaining economic
efficiency and in terms of the “sustainability paradigm.” 相似文献
9.
For the Tuvalu Island group in the western Pacific, a simple graphical method is proposed as a means of forecasting whether
rainfall totals for the next 1, 2,…,6 months will be below average. The method is based on scatter plots where the points
are color-coded as above- or below-average rainfall, with the plot axes being lag-1 and lag-2 NINO4 sea surface temperatures.
Within the scatter plots there are reasonably clear data fields with higher frequencies of below-average rainfalls associated
with cooler precursor NINO4 temperatures. These data fields are defined by subjectively emplaced separation lines which bifurcate
the scatter plots into “predictable” and “unpredictable” fields. If two precursor NINO4 temperature values define a point
located in a predictable field then a warning would be issued for below-average rainfall over the next n-month period, depending on the time scale of the scatter plot. A long rainfall record at Funafuti in Tuvalu indicates that
success in predictable-field forecasting of below-average rainfalls would range between 68% for 1-month rainfall totals and
89% for 6-month totals. The forecasting success derives from persistence of cooler NINO4 sea surface temperatures which are
associated with lower rainfalls in Tuvalu. However, many dry periods are also located in the unpredictable field and cannot
be forecast by this method. 相似文献
10.
The US Geological Survey’s 1995 estimates of domestic undiscovered plus undeveloped natural gas nearly tripled quantities
estimated in its 1989 Assessment. Much of the increase came from selected unconventional resources assessed using the paradigm
of continuous-type accumulations. These include such seemingly unrelated “unconventional” gas occurrences as “tight gas,”
coalbed gas, gas in shales, and deep basin-center gas. Though only a small fraction of the assessed 352 trillion cubic feet
is now economic, the quantity is nevertheless significant. Moreover, the lowest cost resources are close to major gas markets
where competing conventional gas is modest. With continued technological improvements these resources can contribute significantly
to future U.S. gas supply, even without subsidies 相似文献
11.
An oases dynamics model and its application in the Manas oasis 总被引：2，自引：0，他引：2
This study applies theories of systems and system dynamics to ecological economic systems in the oasis environment, with the
intention of finding the basic characteristics of the oasis environment and its feedback structures. This study explores the
inner mechanisms of economic development in the oasis environment and its relationship to policy variables. This model is
applied to economic development in the Manas oasis of the Xinjiang Uygur Autonomous Region of China. System dynamics method
starts from studying feedback structure within the system study and then searches for the best solution through identifying
the right “policy point” and through model simulation in the computer. It embodies the cream of “systems cybernetics theory”.
This study is justified because the nature of the oasis system and the simulation results are scientifically sound and practically
feasible. 相似文献
12.
N. N. Klyuev 《Geography and Natural Resources》2011,32(1):1-8
The concept of territorial justice is developed. The principles of ensuring it are formulated. The method is suggested for
determining the regional dissonances between the manufacture of gross national product and income of the population. The method
offers promise as a necessary coupling tool for identifying potential regions: “donors” and “recipients”. 相似文献
13.
The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are
widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “greatest lake period” may be inferred
by the last highest lake shorelines. They are several, even tens times larger than that at present. According to the analyses
of tens of lakes on the Plateau, most dating data fell into the range of 40-25 ka BP, some lasted to 20 ka BP. It was corresponded
to the stage 3 of marine isotope and interstitial of last glaciation. The occurrence of maximum areas of lakes marked the
very humid period on the Plateau and was also related to the stronger summer monsoon during that period. 相似文献
14.
亚洲国际河流研究进展 总被引：4，自引：0，他引：4
1 General situation Entering the 21st century, resource and environmental diplomacy is regarded as a new element for establishing future international patterns of cooperation. Transboundary resources and environmental issues in international river basins … 相似文献
15.
三江源地区气候变化及其对径流的驱动分析(英文) 总被引：6，自引：3，他引：3
Based on the precipitation and temperature data of the 12 meteorological stations in the "Three-River Headwaters" region and the observed runoff data of Zhimenda in the headwater sub-region of the Yangtze River, Tangnaihai in the headwater sub-region of the Yellow River and Changdu in the headwater sub-region of the Lancang River during the period 1965-2004, this paper analyses the trends of precipitation, temperature, runoff depth and carries out significance tests by means of Mann-Kendall-Sneyers sequential trend test. Makkink model is applied to calculate the potential evaporation. The runoff model driven by precipitation and potential evaporation is developed and the influence on runoff by climate change is simulated under different scenarios. Results show that during the period 1965-2004 the temperature of the "Three-River Headwaters" region is increasing, the runoff of the three hydrological stations is decreasing and both of them had abrupt changes in 1994, while no significant trend changes happen to the precipitation. The runoff model suggests that the precipitation has a positive effect on the runoff depth, while the potential evaporation plays a negative role. The influence of the potential evaporation on the runoff depth of the Lancang River is found to be the significant in the three rivers; and that of the Yellow River is the least. The result of the scenarios analysis indicates that although the precipitation and the potential evaporation have positive and negative effects on runoff relatively, fluctuated characteristics of individual effect on the runoff depth in specific situations are represented. 相似文献
16.
I. Mazzini C. Faranda M. Giardini C. Giraudi L. Sadori 《Journal of Paleolimnology》2011,45(2):243-256
We present a Holocene record of climate and environmental change in central New York (USA) inferred using lithologic and stable
isotope data from two sediment cores recovered in Cayuga Lake. The record was divided into three intervals: (1) early Holocene
(~11.6–8.8 ka), (2) Hypsithermal (~8.8–4.4 ka), and (3) Neoglacial (~4.4 ka to present). The early Holocene began abruptly,
with rising lake level and relatively deep water. Between ~10.8 and 9.2 ka, cool and dry conditions prevailed at a time of
maximum solar insolation. This anomaly has been referred to as the “post-Younger Dryas climate interval” and lasted ~1,600 years,
the approximate length of one “Bond cycle.” The Hypsithermal was the warmest, wettest and most biologically productive interval
of the Holocene in central New York. The Hypsithermal was characterized by centennial to multi-centennial-scale variability.
The 8.2 ka event is one such variation. The Neoglacial was an interval of generally cooler and dryer conditions, falling lake
levels, and several prominent climate anomalies. At approximately 2.4 ka, δ13C of bulk organic matter increased abruptly by 5‰ as lake level declined, and the lake flora was dominated by Chara sp. during the coldest interval of the Neoglacial. Numerous sediment variables display increased variability ~2.0 ka, which continues
today. Archaeological data from the literature suggest that Native American populations may have been large enough to impact
land cover by about 2.4 ka and we hypothesize that the “Anthropocene” began at about that time in central New York. We also
found paleolimnological evidence for the Medieval Warm Period (~1.4–0.5 ka), which was warmer and wetter than today, and for
the Little Ice Age (~500–150 years ago), a period with temperatures colder than today. 相似文献
17.
Assessment of Exploration Bias in Data-Driven Predictive Models and the Estimation of Undiscovered Resources 总被引：3，自引：0，他引：3
The spatial distribution of discovered resources may not fully mimic the distribution of all such resources, discovered and
undiscovered, because the process of discovery is biased by accessibility factors (e.g., outcrops, roads, and lakes) and by
exploration criteria. In data-driven predictive models, the use of training sites (resource occurrences) biased by exploration
criteria and accessibility does not necessarily translate to a biased predictive map. However, problems occur when evidence
layers correlate with these same exploration factors. These biases then can produce a data-driven model that predicts known
occurrences well, but poorly predicts undiscovered resources.
Statistical assessment of correlation between evidence layers and map-based exploration factors is difficult because it is
difficult to quantify the “degree of exploration.” However, if such a degree-of-exploration map can be produced, the benefits
can be enormous. Not only does it become possible to assess this correlation, but it becomes possible to predict undiscovered,
instead of discovered, resources.
Using geothermal systems in Nevada, USA, as an example, a degree-of-exploration model is created, which then is resolved into
purely explored and unexplored equivalents, each occurring within coextensive study areas. A weights-of-evidence (WofE) model
is built first without regard to the degree of exploration, and then a revised WofE model is calculated for the “explored
fraction” only. Differences in the weights between the two models provide a correlation measure between the evidence and the
degree of exploration.
The data used to build the geothermal evidence layers are perceived to be independent of degree of exploration. Nevertheless,
the evidence layers correlate with exploration because exploration has preferred the same favorable areas identified by the
evidence patterns. In this circumstance, however, the weights for the “explored” WofE model minimize this bias. Using these
revised weights, posterior probability is extrapolated into unexplored areas to estimate undiscovered deposits. 相似文献
18.
Unlike other branches of geosciences, exploratory drilling has not been investigated within the framework of an information
system; so, the expression “value of exploratory drilling information” (despite its common usage) is vague. This article presents
a model for the evaluation of value of the information gathered from exploratory drilling after studying different mineral
exploration and exploratory drilling systems within the framework of an “information system.” Although this model does not
present the economic value of information, it is a suitable tool for comparing different drilling patterns. The model was
verified on the basis of drilling data for the Gol-Gohar XIIA anomaly. 相似文献
19.
西辽河流域全新世以来的农业垦殖活动(英文) 总被引：1，自引：1，他引：0
The agricultural reclamations in the Xiliao River Valley since the Holocene have led to a huge landscape change from grassland to farmland. In this paper we reconsider the man-land relationship in the Xiliao River Valley by analyzing three major agricultural reclamations in prehistory, the Liao-Jin Dynasty and the period since the Qing Dynasty. We argue that when the demographic pressure appears in this area, especially during the last reclamation, the intraregional migration (second migration) is the major response to relieve such pressure, which also distinguishes two different settlement locations: "the initial area" and "the secondary area". Due to the environmental differences between these two areas, the cultivation on the latter one has caused more serious disturbance to the local environment. Thus the secondary area has become the key region which needs environmental management seri-ously. 相似文献
20.
Based on energy balance equation and mass transfer equation, a general model to estimate actual evaporation from non-saturated
surfaces was derived. Making use of two concepts, “relative evaporation” and “relative drying power”, a relationship was established
to account for the departure from saturated conditions. Using this model, the actual evaporation (evapotranspiration) can
be calculated without the need of potential evaporation estimation. Furthermore, the model requires only a few meteorological
parameters that are readily and routinely obtainable at standard weather stations. Based on nearly 30 years data of 432 meteorological
stations and 512 hydrological stations in China, in combined with GIS, nine typical river basins were selected. Using the
data of the selected river basins, the model was tested. The results show that the actual evaporation rate can be estimated
with an error of less than 10% in most areas of China, except few years in the Yellow River Basin. 相似文献