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1.
Most states levy severance taxes on the value of natural resources when they are severed or extracted from the ground or subsurface. In Louisiana, severance tax on oil and gas production contributes to the majority of mineral revenue in the state, and over the last decade, has ranged between $400 million and $1.1 billion, or between 5 and 9% of annual state revenue. The purpose of this article is to develop a forecast model for severance tax revenue to better understand the severance tax regime and to assist in state budgeting and planning purposes. We couple an oil and gas production model with empirical relationships describing historical severance tax receipts to perform the forecast. We demonstrate that oil production correlations are robust, but that in recent years, unconventional gas production from the Haynesville shale has led to a significant departure from historic trends. We estimate that cumulative oil and gas severance tax revenues during 2011–2015 will range from $1.0 to $2.1 billion for oil and $1.3–$1.9 billion for gas. Louisiana is transforming into a gas-producing state, and more attention needs to be paid to tax design and the impact of exemptions on future severance revenue receipts.  相似文献   

2.
This study employs (1) a simple econometric model to generate a time series of drilling footage to the year 2040 and (2) learning models to estimate the oil reserve additions from that drilling, given scenarios of oil price and projected U.S. population. Reserve additions are estimated separately for the lower 48 states and Alaska regions by estimating separate drilling footage and learning models for each region. Generally, the estimates of potential supply from undiscovered oil fields and from extensions of known fields are more optimistic than recent estimates by others. For a $1989 price of about $20/barrel (bbl), which is similar to recent prices, the potential supply of oil is estimated to be approximately 60.7 billion bbl, with 95-percent confidence bounds of 54.3 and 67.1 billion bbl. For a price of $25.50/bbl, potential supply is estimated to be approximately 82 billion bbl, with 95-percent confidence bounds of 74.5 and 89.5 billion bbl. Although estimates of potential oil supply for the entire United States are more optimistic than other recent estimates, the part of that supply estimated to be forthcoming from Alaska is smaller than other recent estimates: 2.3 and 3.3 billion bbl for prices of about $20 and $25.50 per barrel, respectively. Thus, reserve additions from the lower 48 states through development drilling and through improved recovery and production technologies will become increasingly important to future U.S. oil supply.  相似文献   

3.
Wilderness attracts tourists and generates visitor spending in proximate communities as people enjoy Wilderness for outdoor recreation. Wilderness also attracts amenity migrants and out-of-region investments into surrounding regional economies. To investigate the amount and types of employment and income generated by Wilderness visitation, we conducted an economic contribution analysis of aggregate national visitor expenditures. The U.S. Forest Service National Visitor Use and Monitoring (NVUM) economic spending profiles were used to construct types and amounts of Wilderness visitor spending and were applied to an estimated 9.9 million annual visitors across federal agencies. IMPLAN modeling software was used to estimate total effects and multipliers for output, employment, income, and value added. Results show that some $500 million is annually spent in communities adjacent to Wilderness, generating a direct effect of 5,700 jobs and a total output effect over $700 million across numerous industries ($2012 including indirect and induced effects).  相似文献   

4.
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5.
Two methods of estimating potential U.S. oil supply are reported: life cycle analysis of updated (1987) oil production data, and an analysis based on learning curve modeling of discovery rates. Based on these analyses, potential U.S. (lower 48 plus Alaska) oil supply (ultimate recoverable oil) is estimated to be 222 billion barrels. A rough inference of the economic reference for this potential oil supply is an oil price of about $20/bbl (1989 dollars).  相似文献   

6.
Forests are major sources of energy, timber and non-timber forest products, medicinal and aromatic plants, hydrological functions, biodiversity conservation, and also fundamental sources of revenue collection to the nation. Studies indicate that forests could significantly enhance economic growth and create employment opportunities for local communities under intensive management. This paper aims to predict the contribution of the forest sector to the national economy. The economic facets of forestry considered in this paper are revenue generated from timber, non-timber forest products (NTFPs) and medicinal and aromatic plants (MAPs), and protected areas. The ARIMA model was used to forecast the economic contribution of the forestry sector. The study found that the total revenue generated from the selling of timber and fuelwood (USD 50.19 million) was higher than the total revenue collected from protected areas (USD 37.58 million) and NTFPs/MAPs (USD 6.9 million) in the past 15 years. The model projected that the mean revenue for the timber and fuelwood sale will USD 3.5 million for the next ten years. Similarly, the mean revenue will be generated about USD 0.5 million and USD 6.2 million from NTFPs/MAPs and protected areas, respectively, for the next ten years. The study limits to take account the in-kind use of forest products such as timber, fodder, fuelwood, etc., as used by community people within a forest users’ groups. Thus, practicing sustainable forest management, enabling policy documents, establishing forest-based industries, establishing forestry nurseries, conducting agroforestry practices, and tenure security could enhance the forestry sector's economic aspects.  相似文献   

7.
Historic exploration and development were used to evaluate the reliability of domestic uranium reserves and potential resources estimated by the U.S. Department of Energy national uranium resource evaluation (NURE) program in the U.S. Gulf Coast Uranium Province. NURE estimated 87 million pounds of reserves in the $30/lb U3O8 cost category in the Coast Plain uranium resource region, most in the Gulf Coast Uranium Province. Since NURE, 40 million pounds of reserves have been mined, and 38 million pounds are estimated to remain in place as of 2012, accounting for all but 9 million pounds of U3O8 in the reserve or production categories in the NURE estimate. Considering the complexities and uncertainties of the analysis, this study indicates that the NURE reserve estimates for the province were accurate. An unconditional potential resource of 1.4 billion pounds of U3O8, 600 million pounds of U3O8 in the forward cost category of $30/lb U3O8 (1980 prices), was estimated in 106 favorable areas by the NURE program in the province. Removing potential resources from the non-productive Houston embayment, and those reserves estimated below historic and current mining depths reduces the unconditional potential resource 33% to about 930 million pounds of U3O8, and that in the $30/lb cost category 34% to 399 million pounds of U3O8. Based on production records and reserve estimates tabulated for the region, most of the production since 1980 is likely from the reserves identified by NURE. The potential resource predicted by NURE has not been developed, likely due to a variety of factors related to the low uranium prices that have prevailed since 1980.  相似文献   

8.
Louisiana plays an important role in domestic oil and natural gas production, and in 2012 ranked sixth in oil production and third in gas production in the United States. Conventional oil and gas production in Louisiana has been declining steadily over the past four decades, while unconventional gas production has seen spectacular growth in recent years, effectively doubling the state’s natural gas output over three years. The structural changes impacting Louisiana’s oil and gas industry are complex and dynamic, and to better understand the relationships between activity drivers, a review of drilling and production data between 1980 and 2011 is performed and correlative relationships are developed. Drilling and completion trends, including completion and success rate statistics and drilled footage, are summarized by region. Correlative relationships are established between measured footage and the number of wells drilled, drilling activity, abandonments, and commodity price. We show that drilling activity in North Louisiana is highly responsive to changing oil prices, whereas in South Louisiana, activity is relatively inelastic. Well abandonments are shown to be negatively related to commodity prices. Horizontal, directional, active, idle, and orphaned well inventories are summarized.  相似文献   

9.
This paper estimates various economic impacts of the annual conferences of the Association of American Geographers (AAG) on the states in which they have been held, from 1983 to 1994. It uses data on the number of registrants at these conferences, the average expenditures and durations of stay of these individuals, and the sectoral distribution of these expenditures. Input-output analysis was employed to estimate the indirect and induced impacts on each state or province. Aggregate expenditures ranged from $890,000 (Denver in 1983) to $2.5 million (Toronto in 1990), while the effect on statewide output ranged from $1.64 million to $4.67 million (same cities). On average, state or provincial output increased by $2.86 million, 90.9 jobs were created, and $717,000 in personal income was generated. These impacts have gradually increased over the time period in question.  相似文献   

10.
Monitoring during three meteorologically different spring seasons in 2012, 2013, and 2014 revealed that temperature increase in spring, which influences spring lake mixing duration, markedly affected nutrient availability and diatom deposition in a sediment trap close to the bottom of deep Tiefer See, NE Germany. Deposition of Stephanodiscus taxa and small Cyclotella taxa was much higher after late ice out and a deep, short lake mixing period in spring 2013, compared to that after gradual warming and lengthy lake mixing periods in spring 2012 and 2014, when only brief or marginal ice cover occurred. Availability of dissolved Si and P was 33 and 20 % higher, respectively, in 2013 compared to 2014. The observed relation between high (low) diatom deposition and short (lengthy) mixing duration in spring was applied to varved sediments deposited between AD 1924 and 2008. Low detrital Si content in trapped material and a sediment core enabled use of µXRF-counts of Si as a proxy for diatom silica. The spring mixing duration for 1951–2008 was derived from FLake-model calculations. The spring warming duration related to lake mixing was approximated from air temperatures for 1924–2008 using the dates when daily mean air temperature exceeded 5 °C (start) and 10 °C (end). Diatom silica deposition showed a significant (p < 0.0001) inverse linear relationship with the modeled spring mixing duration (R2 = 0.36) and the spring warming duration (R2 = 0.28). In both cases, the relationship is strengthened when data from the period of low diatom production (1987–2005) is excluded (R2 = 0.59 and R2 = 0.35). Part of this low diatom production is related to external nutrient supply that favored growth of cyanobacteria at the expense of diatoms. This approach shows that diatom Si deposition was strongly influenced by the availability of light and nutrients, related to the duration of lake mixing and warming in spring, during most of the studied period. The remaining unexplained variability, however, indicates that additional factors influence Si deposition. Further tests in other deep, temperate lakes are necessary to verify if this relation is a common feature and consequently, if diatom Si can be used as a proxy for spring mixing duration in such lakes.  相似文献   

11.
High-resolution, well-calibrated records of lake sediments are critically important for quantitative climate reconstructions, but they remain a methodological and analytical challenge. While several comprehensive paleotemperature reconstructions have been developed across Europe, only a few quantitative high-resolution studies exist for precipitation. Here we present a calibration and verification study of lithoclastic sediment proxies from proglacial Lake Oeschinen (46°30′N, 7°44′E, 1,580 m a.s.l., north–west Swiss Alps) that are sensitive to rainfall for the period AD 1901–2008. We collected two sediment cores, one in 2007 and another in 2011. The sediments are characterized by two facies: (A) mm-laminated clastic varves and (B) turbidites. The annual character of the laminae couplets was confirmed by radiometric dating (210Pb, 137Cs) and independent flood-layer chronomarkers. Individual varves consist of a dark sand-size spring-summer layer enriched in siliciclastic minerals and a lighter clay-size calcite-rich winter layer. Three subtypes of varves are distinguished: Type I with a 1–1.5 mm fining upward sequence; Type II with a distinct fine-sand base up to 3 mm thick; and Type III containing multiple internal microlaminae caused by individual summer rainstorm deposits. Delta-fan surface samples and sediment trap data fingerprint different sediment source areas and transport processes from the watershed and confirm the instant response of sediment flux to rainfall and erosion. Based on a highly accurate, precise and reproducible chronology, we demonstrate that sediment accumulation (varve thickness) is a quantitative predictor for cumulative boreal alpine spring (May–June) and spring/summer (May–August) rainfall (rMJ = 0.71, rMJJA = 0.60, p < 0.01). Bootstrap-based verification of the calibration model reveals a root mean squared error of prediction (RMSEPMJ = 32.7 mm, RMSEPMJJA = 57.8 mm) which is on the order of 10–13 % of mean MJ and MJJA cumulative precipitation, respectively. These results highlight the potential of the Lake Oeschinen sediments for high-resolution reconstructions of past rainfall conditions in the northern Swiss Alps, central and eastern France and south-west Germany.  相似文献   

12.
RURAL-URBAN CLASSIFICATION AND MUNICIPAL GOVERNANCE IN INDIA   总被引：1，自引：0，他引：1  
Rural‐urban classification constitutes an important framework for the collection and compilation of population data in many countries. While “urban” is often specifically defined, “rural” is treated simply as a residual category. The criteria defining urban also differ from country to country. This paper argues that these rural and urban statistical categories are also highly significant for local governance, increasingly so in recent years given the emphasis on local governance and its restructuring. In India, constitutional amendments have given constitutional status to local bodies in the federal structure of the country. Local bodies are thus now expected to draw up their own plans and initiate development works, which requires them to generate their own resources and lessen their dependence on central government funding. It is thus necessary to reorganize urban space into viable spatial units in terms of their revenue base. While rural‐urban classification is the task of the Census of India, state governments are responsible for granting municipal status to urban centres. This paper examines the criteria and limitations of the rural‐urban classification followed by the Census, its congruence with the dynamics of state‐accorded municipal/non‐municipal status and some implications for municipal governance in India.  相似文献   

13.
利用泰尔指数、σ系数、莫兰指数和空间回归模型等方法,对2012—2017年中国大陆346个市域单元收入房价比的时空演变规律进行分析,并探究其影响因素。结果表明:2012—2017年,中国市域单元收入房价比排名整体表现为东部>中部>东北>西部,其相对差异和绝对差异均随时间呈现增大趋势,居民住房支付能力稳步增强。2012—2017年,中国市域单元收入房价比的空间集聚性显著增强,空间分布不均衡性有逐渐增强的趋势。经济水平、城镇化水平、房地产投资水平、城市规模是影响中国市域住房支付能力的主要影响因素,其中,经济水平和城镇化水平对居民住房支付能力具有较大的正向影响,而房地产投资水平和城市规模为负向影响;2012—2017年我国东北和东中西部则不同程度上受不同影响因素的影响。  相似文献   

14.
We examined the potential of geothermal energy development in northern Canadian communities to support local energy demand, along with providing an initial assessment of the economic viability of geothermal energy resources for (a) low enthalpy heating systems and (b) electrical power generation from high temperature resources. We estimate yearly energy production and cost per kWh for geothermal systems using scenarios for thermal and electrical production sustained over 15 years from temperatures reached in the 2–6-km depth range. All the calculations are based on a borehole fluid productivity of 30 kg/s. We assume this to be feasible in sedimentary aquifers and through fractured granites. Under such an assumption and assumptions made on the efficiency of heat exchangers, our modeling shows that thermal energy output for 120°C from 3- to 5-km wells can be as low as 5–8 cents/kWh thermal. For a 6 km depth, the cost of thermal energy can be as low as 1–2 cents/kW thermal for thermal energy production of 100–200 MWh annually.  相似文献   

15.
Freshwater lakes in Antarctica fluctuate from ice-free state (during austral summer) to ice-cover state (during austral winter). Hence the lakes respond instantly to the seasonal climate of the region. The Antarctic seasons respond sharply to the glacial and interglacial climates and these signatures are archived in the lake sediments. A sediment core from Sandy Lake, a periglacial lake located in Schirmacher Oasis of East Antarctica records distinct changes in grain-size, C, N, C/N ratios (atomic), δ13COM and δ15NOM contents during the last 36 ky. The contents of the sedimentary organic matter (OM) proxies (Corg ~ 0.3 ± 0.2%, C/N ratios ~9 ± 5 and δ13COM ~?18 ± 6‰) indicate that the OM in this lake sediment is a product of mixing of terrestrial and lacustrine biomass. Distinctly lower contents of Corg (~0.2%) and sand (~50%), low C/N ratios (~8) and depleted δ13COM (~?20‰) during the Last Glacial Maximum (LGM: 32–17 ky BP based on Vostok Temperatures) suggest greater internal (autochthonous) provenance of organic matter and limited terrestrial (allochthonous) inputs probably due to long and intense winters in the Antarctic. Such intense winters might have resulted the lake surface to be ice-covered for most part of the year when the temperatures remained consistently colder than the Holocene temperatures. The denitrification within the lake evident by enriched δ15NOM (>10‰) during Antarctic LGM might have resulted from oxygen-limitation within the lake environment caused by insulated lake surface. The gradual increases in δ13COM, C/N and sand content starting at ~11 ky BP and attaining high values (~?11‰, ~10 and ~80% respectively) at ~6 ky BP together suggest a subtle change in the balance of sources of organic matter between algal and macrophyte/bryophyte nearly 8–9 ky later to the beginning of the deglaciation. Thus the seasonal opening-up of the Sandy Lake similar to the modern pattern started with the establishment of the optimum temperature conditions (i.e., 0 °C anomaly) in the Antarctic, prior to which the lake environment might have remained mostly insulated or closed.  相似文献   

16.
We describe a dataset of 26 modern diatom samples and associated environmental variables from the Badain Jaran Desert, northwest China. The influence of electrical conductivity (EC) and other variables on diatom distribution was explored using multivariate analyses and generalized additive modeling of species response curves. A transfer function was derived for EC, the variable with the largest unique effect on diatom variance, as shown by partial canonical correspondence analysis. Weighted-averaging partial least squares regression and calibration provided the best model, with a high coefficient of determination ( $ {\text{r}}_{\text{boot}}^{2} $  = 0.91) and low prediction error (RMSEPboot = 0.136 log10 μS cm?1). To assess its potential for palaeosalinity and palaeoclimate reconstructions, the EC transfer function was applied to fossil diatom assemblages from 210Pb-dated short sediment cores collected from two subsaline lakes of the Badain Jaran Desert. The diatom-inferred (DI) EC reconstructions were compared with meteorological data for the past 50 years and with remote sensing data for the period AD 1990–2012. Changes in DI–EC were small and their relationship with climate was weak. Moreover, remote sensing data indicate that the surface areas and water depths of these lakes did not change, which suggests that water loss by evaporation is compensated by groundwater inflow. These results suggest that the response of these lakes to climate change is mediated by non-climatic factors such as the hydrogeological setting, which control recharge from groundwater, and may be non-linear and non-stationary.  相似文献   

17.
Lacustrine records from the northern margin of the East Asian monsoon generate a conflicting picture of Holocene monsoonal precipitation change. To seek an integrated view of East Asian monsoon variability during the Holocene, an 8.5-m-long sediment core recovered in the depocenter of Dali Lake in central-eastern Inner Mongolia was analyzed at 1-cm intervals for total organic and inorganic carbon concentrations. The data indicate that Dali Lake reached its highest level during the early Holocene (11,500–7,600 cal yr BP). The middle Holocene (7,600–3,450 cal yr BP) was characterized by dramatic fluctuations in the lake level with three intervals of lower lake stands occurring 6,600–5,850, 5,100–4,850 and 4,450–3,750 cal yr BP, respectively. During the late Holocene (3,450 cal yr BP to present), the lake displayed a general shrinking trend with the lowest levels at three episodes of 3,150–2,650, 1,650–1,150 and 550–200 cal yr BP. We infer that the expansion of the lake during the early Holocene would have resulted from the input of the snow/ice melt, rather than the monsoonal precipitation, in response to the increase in summer solar radiation in the Northern Hemisphere. We also interpret the rise in the lake level since ca. 7,600 cal yr BP as closely related to increased monsoonal precipitation over the lake region resulting from increased temperature and size of the Western Pacific Warm Pool and a westward shifted and strengthened Kuroshio Current in the western Pacific. Moreover, high variability of the East Asian monsoon climate since 7,600 cal yr BP, marked by large fluctuations in the lake level, might have been directly associated with variations in the intensity and frequency of the El Niño-Southern Oscillation (ENSO) events.  相似文献   

18.
Pronounced climate warming during the past century has been well documented in high-latitude regions. Nonetheless, considerable heterogeneity exists in northern climate trends. We examined the roles of cryospheric landscape and lake depth in modulating the rate and magnitude of local climate responses through a paleolimnological study of lakes from southwest Yukon, Canada. By sampling lakes at varying distances from the Wrangell-St. Elias ice fields, we hypothesized that, for lakes of similar maximum depth, sites closest to the ice fields would be relatively complacent in terms of their chironomid and diatom assemblage changes over the past ~200 years. This hypothesis is based on the moderating effect of the glaciers on local climate, which would be most pronounced in the lakes nearest to the ice fields. However, given the known ecological differences between deep and shallow lakes, we further predicted that, for a given distance from the ice fields, a sediment record from a shallower lake would show the greatest change in stratigraphic subfossil assemblages. Because of the complicated shape of the ice fields, we applied the longitude for each site (which decreases from west to east) to approximate the proximity of our study lakes to the ice fields. Consistent with our predictions, we observed a space-transgressive pattern in the chironomid assemblage turnover that was associated with their proximity to the ice fields (r = ?0.75, P = 0.034, n = 8) across lakes of similar depth (mean maximum depth ± 1, SE = 18.1 ± 2.6 m). Considering a broader network of lakes that represented a greater range in maximum depth (4.9–29 m), we found that differences in subfossil chironomid assemblages between the modern and ca. AD 1800 sediment layers were strongly related to lake depth (r = ?0.77, P < 0.001, n = 15), but failed to detect a significant relationship with latitude or longitude (i.e. our proxy for proximity to the ice fields). Similarly, our comparative high-resolution analyses of two lakes with distinct lake morphometries, but similar proximities to the ice fields, demonstrated the predicted contrasting pattern: we observed pronounced post-1880 changes in the biotic assemblages in the shallow lake and a muted and delayed response (i.e. ~1970s) in the deeper lake. Our findings confirm that cryospheric landscape features can strongly modulate regional climate. Furthermore, our work shows that investigators need to be conscious of how climate change affects the structure and functioning of lakes of different typologies, which influences the way in which paleoclimate signals are recorded and interpreted.  相似文献   

19.
针对陕西省关中区域1978—2017年的农业生产数据,在分析关中40 a农业粮食生产的趋势变化后,运用主成分分析法,对影响关中农业生产中的地理环境和生产投入等主要因素进行了评价研究。结果表明：（1） 关中农业粮食生产的趋势变化呈现周期为3～7 a的循环增长方式,平均每周期峰值增长率为4.5%。（2） 主成分分析研究后得出,第一主成分全是地理因素指标,方差贡献率达到0.554,对关中地区农业粮食生产起着非常显著的决定影响作用,包括受灾农田面积（不含病虫害）、主要粮食作物播种面积、成灾农田面积（不含病虫害）、有效灌溉耕地面积、耕地面积;第二主成分方差贡献率为0.25,是影响粮食生产的重要因素和农业生产的生命补给。包括农业用电量、化肥、农用机械等生产资料投入和主要粮食作物稳产面积、劳动力投入因素指标;第三主成分为农药应用量,方差贡献率为0.068,影响较小。主成分累计方差贡献为0.872。通过对关中地区农业粮食生产变化的影响因素分析,可以为政府部门提出数据支撑和相关性的建议。  相似文献   

20.
Satisfying the food demands of an ever-increasing population, preserving the natural resource base, and improving livelihoods are major challenges for South Asia. A large area of land in the Middle and Lower Gangetic Plains of South Asia remains either uncultivated or underused following the rice harvest in the kharif (wet) season. The area includes “rice-fallow,” estimated at 6.7 million ha, flood-prone riversides (“diara lands,” 2.4 million ha), waterlogged areas (4.9 million ha), and salt-affected soils (2.3 million ha). Bringing these lands under production could substantially improve the food supply and enhance livelihoods in the region. This paper describes a methodological case study that targeted resource-conserving technologies in underused lands of the Ballia District of eastern Uttar Pradesh (India) using multispectral remote-sensing images. Classification of temporal satellite data IRS-P6 in combination with Spot VGT 2 permitted the identification of all major categories of underused land during the post-rainy rabi/winter season, with an average accuracy of 89%. Based on three-year averages of field demonstrations, farmers gained an additional income of $63 ha−1 by introducing raised beds in salt-affected soils; $140 and $800 ha−1 by introducing deepwater rice varieties (monsoon) and boro rice (winter) in waterlogged areas; and $581 ha−1 by introducing zero-till lentil (winter) in rain-fed fallow lowland. Timely wheat planting through zero-tillage implies an additional income of $147 ha−1 and could increase wheat production by 35,000-65,000 tons in the district. The methodologies and technologies suggested in the study are applicable to more than 15 million ha of underutilized lands of the Indo-Gangetic Plains of South Asia. If the technologies are precisely applied, they can result in more than 3000 million US $ of additional income every year to these poverty prone areas.  相似文献   

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