旅游需求波动、风险管理与非线性减贫效应研究

旅游发展能够有效匹配贫困人口的资源禀赋,是产业扶贫的重要支撑。为更好地发挥旅游的减贫效用,本文基于旅游波动和风险管理视角对旅游发展与贫困减缓的多样化关联进行了逻辑统一,在使用HP滤波方法测度旅游需求波动的基础上,使用门限面板模型对2000-2013年中国旅游发展的非线性减贫效应进行了实证检验。实证结果显示:旅游波动是影响旅游发展减贫效应的重要因素,但国内旅游波动和入境旅游波动的减贫效应存在异质性。国内旅游波动主要体现为上行波动,能够在增长的稳定预期下,有助于旅游企业和包括贫困人口在内的旅游从业者进行专业化供给,从而有助于减贫。旅游发展的减贫效应体现出双门限的非线性特征,在旅游发展的初始阶段,并未能体现出显著的减贫效果,越过第一个门限值后,旅游减贫效应开始凸显,但在第二门限值之后,处于第三阶段旅游发展减贫弹性递减。因此,旅游产业具备成为阶段性重要减贫动力来源的潜力,但在旅游扶贫政策的制定和实施中,应秉持辩证和动态视角,当意识到旅游减贫效应已经步入递减区间时,要进行主动、系统、综合的风险管理。理解外部环境变化对旅游发展冲击的潜在结果,通过旅游需求结构和产业结构的调整提升贫困人口应对风险冲击的韧性,并通过互助、保险等风险应对手段,促进资源在不同风险状态之间的转移,提升旅游减贫绩效。     

Mapping the global supply and demand structure of rice

Rice plays a major role in the global supply and demand for sustainable food production. The constraints of maintaining sustainable rice production are closely linked to the relationship between the distribution patterns of human activity on the planet and economic growth. Global patterns of rice production can be mapped by using various criteria linked to domestic income, population patterns, and associated satellite brightness data of rice-producing regions. Prosperous regions have more electric lighting, and there are documented correlations between gross domestic product (GDP) and nighttime light. We chose to examine global rice production patterns on a geographical basis. For the purposes of this study, each country is considered to be made up of regions, and rice production is discussed in terms of regional distribution. A region is delineated by its administrative boundaries; the number of regions where rice is produced is about 13,839. We used gridded spatial population distribution data overlain by nocturnal light imagery derived from satellite imagery. The resultant relationship revealed a correlation between regional income (nominal values of GDP were used) and rice production in the world. The following criteria were used to examine the supply and demand structure of rice. Global rice consumption = “caloric rice consumption per capita per day” multiplied by “regional population values”. Regional rice yields = “country-based production” divided by “harvested area” (multiple harvests are taken into account). Regional rice production = “regional harvested areas” multiplied by “rice yield values”. We compared regional rice consumption and production values according to these methods. Analysis of the data sets generated a map of rice supply and demand. Inter-regional shipping costs were not accounted for. This map can contribute to the understanding of food security issues in rice-producing regions and to estimating potential population values in such regions.     

The challenge of adapting centralised electricity systems: peak demand and maladaptation in South East Queensland,Australia

South East Queensland’s (SEQ’s) centralised electricity system is under great pressure to adapt. Climate change is converging with socio-economic, demographic and technological changes to create a ‘perfect storm’ for the region’s electricity system. Distribution networks are particularly affected, with these factors contributing to tremendous peak demand growth, about double the rate of growth in average demand in recent years. This paper reviews how Australia’s electricity system is adapting to multiple drivers of peak electricity demand. We use socio-technical transitions theory to understand the temporal interconnected social and technical dimensions of adaptation in this setting. Specifically, we present an historical narrative of the emergence of centralisation in Australia and outline the peak demand problem in SEQ and review adaptation options from the international literature. We also analyse the interactions between key social groups and their adaptation responses over the past decade. Our analysis shows that adaptation has become a contested process between supply-chain actors and end-users, each with different economic objectives, adaptation needs and capacities. The resulting adaptation dynamic that is emerging shows worrying signs of maladaptation. Implications for market governance and urban policy and research are discussed.     

Social demand for multiple benefits provided by Aleppo pine forest management in Catalonia,Spain

This paper estimates the social demand for key benefits provided by Aleppo pine forests in Catalonia that can be enhanced by management. These so-called externalities are the side effects of forest management on citizens’ welfare and can be either positive or negative. The externalities addressed are: biodiversity (measured as the number of tree species), accessibility for practicing recreational activities, CO₂ sequestration and annual burned area by wildfires. By the use of a choice experiment, an economic valuation method, we estimate in a joint manner people’s preferences for these externalities and show that there is a social demand for their enhanced provision. Based on these estimates, we construct three hypothetical scenarios reflecting the range of likely outcomes of different management strategies and calculate the social demand for these scenarios. Results show that the highest gains in terms of social benefits are obtained under a scenario that minimizes the burned area (2044.23 €/ha year). Our estimates show that an increase in the investment in forest management is in line with the social demand for forest benefits and the social support that exists for a related cost increase for inhabitants.     

Air pollution and the demand for hospital services: a review

Time-series studies published since 1993 on the association between short-term changes in air quality and use of hospital services, including both inpatient and emergency room use, are reviewed. The use of nonparametric analysis, often incorporating generalized additive models (GAMs), has increased greatly since the early 1990s. There have also been three major multi-city studies, which together analyzed data from well over 100 cities in Europe and North America. Various air pollutants, especially ozone (O(3)), particulate matter (PM), nitrogen dioxide (NO(2)) and sulfur dioxide (SO(2)), were generally found to be significantly associated with increased use of hospital services. Ozone tends to have stronger effects in the summer during periods of higher concentrations. Several studies revealed synergistic effects between pollutants such as PM and SO(2). Overall, short-term exposure to air pollutants is found to be an important predictor of increased hospital and emergency room use around the world.     

Water demand of central pivot-irrigated areas in Bahia,Brazil: management of water resources applied to sustainable production

When performed without technical criteria, the rapid expansion of irrigated agricultural frontiers can result in overexploitation of water, causing worrying impacts on the balance of agroecosystems. This study proposes a model applied to the state of Bahia, to estimate the water demand of areas irrigated by a central pivot, in order to contribute to information that will subsidize the inspection and planning of water resources in the promotion of sustainable agriculture. The irrigated areas were identified and measured by photointerpretation using orbital images from the Landsat-8 satellite. With a historical series of data, the reference evapotranspiration was calculated and monthly water balance was elaborated. The data obtained were spatialized by kriging, and with punctual values of water deficit (mm), the water demand of the irrigated perimeter of the equipment was estimated. The results were described considering strategic planning units, proposed from municipalities, hydrographic basins and biomes. A total of 4075 pivots were quantified, covering an irrigated area of 265,896.30 ha and with an average annual consumption of 1,333,473,208.02 m³ of water. Areas of high demand were identified, especially in the western region of Bahia, which includes the hydrographic basin of the São Francisco River and the Cerrado biome, concentrating 80.85% and 75.47% of the state water demand for pivots, respectively. Considering possible points of water vulnerability and continuity of this expansion, the results provide the primary information needed to encourage the adoption of public policies aimed at the management of water resources. The study method proposes guidelines that condition the application in any region of interest in the world.

Graphical abstract

     

碳排放交易体系的构建、挑战与市场拓展

碳排放权通过市场交易实现效率配置,有理论与实践支撑。"碳排放"作为一种"恶品",需要不断压缩或定额管控,与"善品"有着本质不同。因而,"碳排放"市场交易有着固有的困境。在国内碳市场构建中,困境还会得到强化。因为,1中国与国际社会、中央与地方、地方之间、政府与企业存在多重博弈,受经济、政治、环境、社会多重因素的制约,排放总量的确定和分配具有潜在的不确定性。2"碳"的核算从属于能源,并不完全独立,是一种具有被动属性的交易品,企业的选择与能效和节能关联,则"用能权"和"碳排放权"重叠。由于碳作为交易品的从属和被动属性,企业的经营决策的碳约束可能被弱化或边缘化,对消费者的价格信号部分失真。3开放的、竞争的市场才是有效率的。但是从欧盟的碳排放贸易体系和国内的试点看,这一系统则是相对封闭的。4如果说高碳产品低品质可以通过市场的自我调节而对企业有所约束,而城市基础设施锁定的碳,其成本只能由全社会担承,在碳排放交易体系中得不到实际体现。5用能权和碳排放权有可能一体兼容,但是,碳交易的市场激励传递受到一些体制性因素的约束而失效。因此,中国的碳交易体系构建,需要在顶层设计中考虑碳排放的属性特点,拓展碳排放交易的市场空间。首先,在认知上将"碳交易"从约束变为一种机遇。其次,国家需要将碳纳入预算管理,实现效率配置和有效管控。再次,建立发展导向的碳交易市场,拓展碳市场规模。如纳入森林碳汇,碳市场与生态补偿相关联。最后,鼓励净零碳城市建设。     

Spatio-temporal modelling of electric vehicle charging demand and impacts on peak household electrical load

This paper presents a composite methodology for obtaining spatial and temporal projections of charging demand and peak-shaving potential from plug-in electric vehicles (EVs), and the associated spatio-temporal impacts on peak household electrical load. The methodology comprises a suite of models of future EV uptake, travel by households, household electricity demand and recharge/discharge of EVs at their home locations. The analysis is disaggregated to hourly time-steps over a full year, and spatially to mesh blocks comprising around 250 houses per block. The modelling suite is applied to an analysis of peak household load impacts across the state of Victoria, Australia, under nine different combinations of EV uptake and charging/discharging behaviour. The projected increase in peak household electrical loads under expected penetration rates and charging demands is less than 10 % on most high-demand days, but can be up to 15 % on a handful of days and geographic locations. Peak-load impacts under off-peak charging are mostly less than 5 %. With judicious EV discharging strategies, there is potential to shave peak loads on the highest demand days by up to 5 %.     

Robust optimization approach to two-echelon agricultural cold chain logistics considering carbon emission and stochastic demand

Environment, Development and Sustainability - Cold chain logistics has become one of the main sources of carbon emissions. Meanwhile, the implementation of low-carbon economy has become an...     

Reducing carbon footprint and cooling demand in arid climates using an integrated hybrid ventilation and photovoltaic approach

Environment, Development and Sustainability - A hybrid ventilation system combining both natural and mechanical ventilation has proven very promising in moderating indoor climate, based on its...     

Multiscale system dynamics of humans and nature in The Bahamas: perturbation, knowledge, panarchy and resilience

The analysis of the dynamic interactions between social systems, integrated by governance and communication, and biophysical systems, connected by material and energy flows, remains a challenge. In this paper, we draw on the heuristic models of the “adaptive renewal cycle” and “panarchy” [Gunderson and Holling (eds) Panarchy: understanding transformations in human and natural systems. Island Press, Washington, 2002], which are embedded in the theory of complex adaptive systems. Taking island development research in The Bahamas as a case study, we investigate environmental stressors, knowledge and social response in the context of three distinct social–ecological subsystems: (1) the interaction between tropical storms/hurricanes and the social system of disaster preparedness/management; (2) coastal ecosystem degradation coupled with land development; and (3) the fishery, in which we also consider the impact of a recent biological invasion, the Indo-Pacific red lionfish. The findings demonstrate the complexity of panarchical relations and the crucial role of diverse and uncertain knowledge systems and underlying mental models of risk and environment for resilience and sustainability. These are acquired at different scales and form key variables of change. This also applies to processes of communication. Bringing together the various constantly evolving multi-level knowledge systems for effective communication and decision-making remains a major challenge.     

Closed-loop supply chain system with energy,transportation and waste disposal costs

Energy usage and consumption play important and strategic roles in modern manufacturing, inventory and logistics systems. The literature on inventory models for closed-loop supply chains reveals that, for no clear reasons, energy costs were ignored along with transportation and disposal costs. This paper introduces a closed-loop supply chain model that considers the economic value and energy content of products. It also offers a novel framework for studying lot-sizing policies of production processes in that context. Thus, a mathematical model for a closed-loop supply chain system with energy, transportation and disposal costs is developed. Numerical examples are provided with their results discussed. The developed model was also compared to that of Richter (1996) to stress the importance of accounting for the three noted costs. The numerical results emphasise that accounting for energy, transportation and disposal costs in supply chain modelling increases the sustainability of a production-inventory system due to the strong interdependence of the three costs on one hand, and their relationship to the environment on the other hand.     

Environmental demand effects on the energy generation of Karkheh reservoir: Base and climate change conditions

Environment, Development and Sustainability - Reservoir is a hydraulic structure that regulates river water to supply different sectors’ demands such as municipal, agricultural, and...     

Dynamics of leaf litter and soil respiration in a complex multistrata agroforestry system,Pernambuco, Brazil

High litter inputs in agroforestry systems contribute to soil microbial activity, soil fertility and productivity. Considering that the cycling of organic matter is essential to the maintenance of physical–chemical and microbiological properties of the soil, the aims of this work were to estimate the production, accumulation and decomposition of litter, and assess soil microbial respiration in a complex multistrata agroforestry system located in the north-east of Brazil. This agroforestry system has three strata formed by forest and fruit trees and species of multiple uses. During 3 years (2011–2013), leaf litter was sampled monthly to account for litterfall and quarterly to account for litter accumulation. The rates of litter decomposition were estimated using the ratio produced-to-accumulated litter, and the correlation between litter fall and rainfall was calculated. Precipitation data were provided by the water and climate agency of Pernambuco (APAC). Soil samples (0–15 cm) were also taken quarterly, simultaneously with the litter accumulation samples, and soil microbial respiration was assessed using the capture, by a KOH solution, of the evolved CO₂. The annual production of leaf litter was stable in the 3 years of study in this agroforestry system, and the monthly input of litter to the soil was influenced by rainfall, being higher in the dry seasons. The accumulated litter on the ground was constant, as was microbial activity (respiration) through time. The estimated litter decomposition rates were 1.49 (first year), 1.33 (second year) and 1.42 (third year), being considered rapid rates of decomposition. This guarantees (to the farmer) that this system is capable of maintaining soil fertility and eliminates the need for chemical fertilizers.     

Analysis of the energy demand of the Chilean mining industry and its coverage with solar thermal technologies

The mining industry represents more than half of Chile’s foreign exchange earnings and its increasing expansion will demand a continuous development of its energy supplies. Mostly, all the mines in Chile are located in the desert regions, having a large surface with one of the highest solar radiations levels and clearest skies in the world. Covering the mining industry’s energy demand with solar energy is thus an obvious and promising approach. In this paper, the implementation of solar thermal heating is studied in every mining process and the solar thermal electricity generation for the entire mine demand is considered as well. The work concludes that the installation of flat plate collectors to heat water for mine processes, especially for electrowinning, is strongly recommended. Additionally, the installation of solar thermal power plants can satisfy the mining electricity demand.     

Environmental management systems in the architectural,engineering and construction sectors: a roadmap to aid the delivery of the sustainable development goals

Environment, Development and Sustainability - Realisation of the sustainable development goals (SDGs) will provide improvements to people's lives and longevity of the planet. The architectural,...     

Willingness to pay and demand elasticities for two national parks: empirical evidence from two surveys in Pakistan

Using survey-based data approach for modeling the demand for environmental goods/resources, this study estimates income and price elasticities of demand for improved environmental quality of two National Parks in Northern Pakistan. The study uses data from two studies. The estimates indicate that improved environmental quality effects can be described as a luxury and an ordinary and price elastic service. Confidence intervals show however that the classification as a luxury is not statistically significant. Income elasticities of willingness to pay are estimated for a broad range of environmental services. The study finds that income and willingness to pay vary directly and significantly. The elasticity estimates, in general, are greater than zero, but less than unity. The study concludes that environmental improvements are more beneficial to low-income groups than for high-income groups.

Design,measurement and evaluation of photovoltaic pumping system for rural areas in Oman

In the present paper, the optimum design of a PV system used to operate a water pumping system was determined for Oman. The system design focused on the environmental conditions of Sohar city. The implementation and measurement of the designed system are presented to prove the effectiveness of the proposed system. The results show that the system can provide the required power at peak hours, leading to a substantial reduction in the sizing of the PV system. Consequently, the investment capital costs 2400 USD, and the cost of energy is equal to 0.309 USD/kWh. Furthermore, the results indicate that the system annual yield factor is 2024.66 kWh/kWp and that the capacity factor is 23.05 %, which is encouraging since the latter is typically 21 %. The system capital cost and the cost of energy are worth comparing to a diesel generator. A comparison is made between the proposed system and several others in the literature. The comparison indicated that the system cost of energy is promising.