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1.
An increasing demand for food together with a growing demand for energy crops result in an increasing demand for and competition over water. Sugar cane, sugar beet and maize are not only essential food crops, but also important feedstock for bio-ethanol. Crop growth requires water, a scarce resource. This study aims to assess the green, blue and grey water footprint (WF) of sweeteners and bio-ethanol from sugar cane, sugar beet and maize in the main producing countries. The WFs of sweeteners and bio-ethanol are mainly determined by the crop type that is used as a source and by agricultural practise and agro-climatic conditions; process water footprints are relatively small. The weighted global average WF of sugar cane is 209 m3/tonne; for sugar beet this is 133 m3/tonne and for maize 1222 m3/tonne. Large regional differences in WFs indicate that WFs of crops for sweeteners and bio-ethanol can be improved. It is more favourable to use maize as a feedstock for sweeteners or bio-ethanol than sugar beet or sugar cane. The WF of sugar cane contributes to water stress in the Indus and Ganges basins. In the Ukraine, the large grey WF of sugar beet contributes to water pollution. In some western European countries, blue WFs of sugar beet and maize need a large amount of available blue water for agriculture. The allocation of the limited global water resources to bio-energy on a large scale will be at the cost of water allocation to food and nature.  相似文献   

2.
The study assesses green and blue water footprints (WFs) and virtual water (VW) trade in China under alternative scenarios for 2030 and 2050, with a focus on crop production, consumption and trade. We consider five driving factors of change: climate, harvested crop area, technology, diet, and population. Four scenarios (S1–S4) are constructed by making use of three of IPCC's shared socio-economic pathways (SSP1–SSP3) and two of IPCC's representative concentration pathways (RCP 2.6 and RCP 8.5) and taking 2005 as the baseline year. Results show that, across the four scenarios and for most crops, the green and blue WFs per tonne will decrease compared to the baseline year, due to the projected crop yield increase, which is driven by the higher precipitation and CO2 concentration under the two RCPs and the foreseen uptake of better technology. The WF per capita related to food consumption decreases in all scenarios. Changing to the less-meat diet can generate a reduction in the WF of food consumption of 44% by 2050. In all scenarios, as a result of the projected increase in crop yields and thus overall growth in crop production, China will reverse its role from net VW importer to net VW exporter. However, China will remain a big net VW importer related to soybean, which accounts for 5% of the WF of Chinese food consumption (in S1) by 2050. All scenarios show that China could attain a high degree of food self-sufficiency while simultaneously reducing water consumption in agriculture. However, the premise of realizing the presented scenarios is smart water and cropland management, effective and coherent policies on water, agriculture and infrastructure, and, as in scenario S1, a shift to a diet containing less meat.  相似文献   

3.
Abstract

In despite of fluctuation in recent years, the grain yield in China has been increasing, which relieves the conflict between supply and demand and turns the situation of food security good. However, because of the rapid increase in food consumption, the conflicts of food quality and structure in the supply and demand equilibrium has become more and more obvious and the long-effective mechanism of food security has not been established yet. It is found that the factors affecting food security in China include the scarcity and dissipation of resources, farmers’ low enthusiasm in planting grain crops and the inappropriateness of the emphasis and measures of macro-economic regulation and control. Therefore, the authors advance to optimize resources allocation, strengthen macro-economic regulation and control and policy stimulation and establish the mechanism of allocating grain production cost, to set up the long-effective mechanism of China food security and keep it stable in the long term.  相似文献   

4.
In despite of fluctuation in recent years, the grain yield in China has been increasing, which relieves the conflict between supply and demand and turns the situation of food security good. However, because of the rapid increase in food consumption, the conflicts of food quality and structure in the supply and demand equilibrium has become more and more obvious and the long-effective mechanism of food security has not been established yet. It is found that the factors affecting food security in China include the scarcity and dissipation of resources, farmers' low enthusiasm in planting grain crops and the inappropriateness of the emphasis and measures of macro-economic regulation and control. Therefore, the authors advance to optimize resources allocation, strengthen macro-economic regulation and control and policy stimulation and establish the mechanism of allocating grain production cost, to set up the long-effective mechanism of China food security and keep it stable in the long term.  相似文献   

5.
Climate change phenomenon can be seen as a simple but daunting problem. The lack of equity in emission reduction burden sharing regime, will cause a need for a greater sacrifice for poor or less developed countries. Thus, the evaluation of different aspects of equity at a national scale and presenting a top–down model of equity for allocation of GHGs emission (such as GERA) in line with sustainable development is the main objective of this study. In this study, the five equity principles proposed in the literature namely (1) population distribution, (2) GHGs emissions, (3) GDP, (4) trend of economic growth and (5) per capita of carbon productivity as appropriate criteria of equity estimation. Due to the different decision makers' preferences, different weights are allocated to indicators and analyzed. Iran has been considered as a case study, and these criteria were applied at national level to propose an allowance allocation scheme. The result of applying GERA for Iran, at provincial level and under the five equity criteria, determines which provinces have to shoulder higher reduction burdens, and makes a room for less developed provinces for growth. Based on these results, this model demonstrated to be more sensitive to criteria selection rather than to the weight factors. In addition, shifting to low carbon technologies or renewables, careful evaluation of current emission–income pattern, improving of energy intensity and finally, adjustment of secondary industries (manufacturing) based on ecological and natural resources of each region are suggested as the most efficient approaches toward sustainability and green development for the case study.  相似文献   

6.
Universal two-child policy has been implemented since the end of 2015 in China. This policy is anticipated to bring a significant increase in the total population, with profound influences on the resources and environment in the future. This paper analyzes the changing dynamics of urban and rural population, and forecasts urban and rural population from 2016 to 2030 at national and provincial scale using a double log linear regression model. Drawing upon the results of these two predictions, the impact of the population policy change on Chinese resources consumption and environmental pollution are predicted quantitatively. Given the future total population maintains current levels on resources consumption and environmental emission, the additional demand of resources and environment demand for the new population is forecasted and compared against the capacity on supply side. The findings are as follows: after implementing the universal two-child policy, China’s grain, energy consumption, domestic water demand, and pollutant emissions are projected to increase at different rates across provinces. To meet the needs arising from future population growth, food and energy self-sufficiency rate will be significantly reduced in the future, while relying more on imports. Stability of the water supply needs to be improved, especially in Beijing, Henan, Jiangsu, Qinghai, and Sichuan where the gap in future domestic water demand is comparatively larger. Environmental protection and associated governing capability are in urgent need of upgrade not least due to the increasing pressure of pollution.  相似文献   

7.
Thailand plays an important role in the international trade of food and agricultural products, which is in alignment with its national strategy of serving as the “kitchen of the world.” When looking at its agricultural promotion and export policies, the country only counts the value gains from exports while neglecting environmental externalities related to plantation practices. The purpose of this study was to perform a trade-off analysis between consumptive water, land, and fertilizer use together with the economic values of major crops for export and consumption in the country. The results show that to gain income from agricultural exports, the country has exploited various natural resources. The area used to harvest rice, sugarcane, cassava, and rubber adds up to approximately 15.3 million ha: 7.2 million ha of which is for domestic consumption and 8.1 ha for export. To produce Thailand’s agricultural exports, total water use is estimated to be 49.8–67.5 billion m3 per year (61–65 %), while the amount used to produce crops for domestic consumption is 26.5–43.7 billion m3 per year (35–39 %). Meanwhile, 1,056–1,826 thousand tons (54 %) of fertilizer was used on crops for domestic consumption, and 1,222–1,370 thousand tons (46 %) of fertilizer was used on export crops. The best crop choice for export in terms of its export value, land use, fertilizer use, and water consumption is rubber. The worst crop choices for export are rice and cassava. More sustainable agricultural practices are needed to effect improvements such as increased yields and reduced fertilizer and water use.  相似文献   

8.
China’s large population and deteriorating environment have created great concern related to the sustainability of food production, especially since details related to this topic remain poorly studied. Thus, an integrated analysis of both crop yield and cultivated area is essential for gaining a better understanding of cereal grain production in China and for making corresponding policies designed to achieve food security. In this study, we adopt trend analysis of both provincial yield and cultivated area to assess the subsequent provincial-level cereal production sustainability between 1980 and 2011 with the goal of providing a better understanding of regional agricultural development. The results indicate that while maize shows the most promise for yield improvement, rice and wheat production is experiencing substantial yield stagnation among most provinces across mainland China. In addition, the trends in spatial patterns are prominently different from those of yields. The sizes of the main rice- and wheat-growing areas in China have declined greatly, suggesting that the related production of these cereals should attract more attention from land management planners and farmers. Specifically, the south-eastern coastal provinces have largely failed to sustain both crop yield and area, while the north-eastern provinces have witnessed thriving agricultural production during the last three decades. Moreover, we find that cereal production in China is significantly affected by governmental policies related to the agricultural sector. Thus, this analysis of food production in China will help policymakers to better understand how the potential implications of food security in China may be applicable to countries worldwide.  相似文献   

9.
China produces the largest amount of pork in the world, which emits the largest amount of greenhouse gases (GHGs). This paper calculates GHG emissions from China’s hog production at the provincial level using newly published emission factors. Empirical results show that GHG emissions from China’s hog production mainly respond to the scale intensity. Capital abundance and income contribute positively to GHG emissions from hog production. Pork trade increases GHG emissions from China’s hog production with a significantly direct effect, reduces GHG emissions through indirect technique effects.  相似文献   

10.
贵阳市循环经济发展度量的研究   总被引:16,自引:0,他引:16  
循环经济指标体系旨在度量区域循环经济发展的系统目标和工作进展。该文在“驱动力-压力-状态-响应”(DPSR)框架下设计度量区域循环经济发展的指标体系,含有状态指标、压力指标、驱动力指标、响应指标以及分离指标共5类指标集合。其中,分离指标集合作为循环经济的特征指标来表征经济发展与资源投入和污染产出分离的效果和趋势。考察贵阳循环经济规划案例表明:贵阳如果走循环经济的发展道路,可以转变经济增长方式,实现经济增长与资源投入和污染产出的分离。  相似文献   

11.
ABSTRACT

China’s domestic oil production has lagged the growth in domestic oil consumption since the beginning of the 21st century, leading to a growing reliance on imports. In response, the Chinese government has introduced a number of policies, including import license constraints, to support domestic suppliers. In an effort to measure the economic impact of these policies we develop a short-run equilibrium model of China’s wholesale oil and gas market at the provincial scale. We construct counterfactual scenarios that suggest that relaxing policies that prioritize domestic production in 2016, when the average price of Chinese oil imports was US$42 per barrel (bbl), could have increased China’s import demand by 0.29 million barrels per day (MMbbl/d). This results in a substitution of 9% of China’s domestic production in 2016, and a reduction of US $2.8 billion in crude supply costs including transportation as the imported oil has more direct access to the country’s pipeline network, compared to the displaced domestic production. In addition, rising import prices since mid-2017 may provide a window of opportunity for Chinese policymakers to proceed with further deregulation of the domestic oil sector, as the short-term impact on domestic producers is reduced.  相似文献   

12.
中国工业用水效率的动态演进及驱动因素研究   总被引:1,自引:0,他引:1  
选取中国31个省级行政区1999~2014年的面板数据,运用Frontier4.1软件测算了我国各省区历年工业用水效率值,还通过聚类分析方法将各省区分为高效率组、中效率组、低效率组进行工业用水效率差异分析,接着选择自然资源、经济水平、工业发展、工业结构、用水结构和政府影响这6个因素,构建Tobit回归模型对这6个驱动因素分全国、高、中、低效率组样本分别对工业用水效率的影响进行实证分析。研究结论如下:我国工业用水效率平均值呈现逐年上升的趋势;东、中、西部地区的工业用水效率值差异较为明显;工业用水效率整体分布从东南向西北逐渐递减的趋势;我国各省区的工业用水效率处于一种较快的增长趋势且地区间的工业用水效率差距在不断缩小;人均水资源量与工业用水效率呈负相关关系;经济水平驱动因素和工业发展驱动因素都与工业用水效率存在很强的正相关关系;合理的工业结构可以显著提高工业用水效率;政府作为对于工业用水效率的提高也是至关重要的。  相似文献   

13.
长江流域的水资源配置与水资源综合管理   总被引:16,自引:7,他引:9  
回顾总结了我国近年来在水资源配置方面的理论研究和工作进展,论述了我国水资源配置的特点及其与联合国倡导的水资源综合管理的相互关系,阐述了长江流域水资源综合管理在我国的重要地位。提出我国开展的水资源配置在重视公众参与的基础上,与水资源综合管理是一致的。长江流域水资源综合管理是一个多学科、跨学科的研究课题。流域层面的水资源综合管理是国家层面和行业层面水资源配置的基础。长江水资源综合管理应该遵循水文系统优先的原则,使水资源利用和管理在流域层面上首先达到优化状态。环境用水需求是一个重要课题,它是流域层面水资源配置的基础,急待开展大量的研究。在流域系统优先原则下,各行政区与水用户参与者在讨论和协商的基础上,确定共同的准则、目标和具体措施,在不损害它方利益的前提下都能取得自己的利益。具体细化新《水法》中提出的流域管理与行政管理相结合的原则是开展长江水资源综合管理的关键。《长江法》的制定应该为水资源综合管理提供具体的法律依据。流域与地方水利机构的体制改革是十分重要的,它应该为开展水资源综合管理创造条件。在我国国情条件下,水资源综合管理中的用户参与应该如何开展,需要研究和实践。  相似文献   

14.
中国农产品虚拟耕地与资源环境经济要素的时空匹配分析   总被引:1,自引:0,他引:1  
计算出1999~2009年中国各地区农产品虚拟耕地与人口、水资源、耕地资源、水土流失治理以及GDP等要素的基尼系数以及全国8大区域2009年农产品虚拟耕地 资源环境经济要素的不平衡指数。结果表明:(1)我国农产品虚拟耕地与各资源环境经济要素的地域分布匹配程度都不高;其中农产品虚拟耕地与人口、耕地的地域匹配程度相对较高,与水土流失治理之间的地域匹配状况次之,与GDP和水资源的地域匹配程度相对较低;(2)我国农产品虚拟耕地与各资源环境经济要素的外部公平性不高,黄淮海地区为农产品虚拟耕地 资源环境经济要素不公平性最突出地区,其次是华南、西北和东北地区  相似文献   

15.
粮食安全:气候变化与粮食产地转移   总被引:2,自引:0,他引:2  
基于1985-2008年中国雀际面板数据,实证检验了气候变化对粮食种植规模与单位产量的作用机制,进而分析了产地转移对国家粮食总供给的影响.结论表明:①中国的稻谷、小麦、玉米产业正分别向黑龙江、河南、内蒙古等气候资源匮乏地区转移或集聚;②粮食产地转移的主导因素在于粮食作物与经济作物、种植业与畜牧业、农业与非农的成本收益比较,而气候变化因素仅处于附属地位;③基于规模效应、牧入效应以及回弹效应的作用机制,东北三省、河南、内蒙古等地区的增长潜质往往优于其他地区;④落后地区应对气候变化的生产与政策成本,往往要低于发达地区保留粮食生产的机会成本,粮食生产向欠发达地区转移应具有可持久性.粮食产地转移过程中,并未呈现粮食供给安全的“个体理性”与“集体理性”的冲突.中国应该在气象预报、水利设施、抗灾能力、中低产田改造等方面加大投入,摒弃区内平衡的传统观念,在全国范围内优化资源配置,并辅以国家粮食储备战略应对特大灾害的供给风险.  相似文献   

16.
经济全球化背景下,中国工业化进程深度融入全球价值链分工体系,在以资源能源消耗与要素投入增加为特征的粗放型经济增长模式下,国际贸易与国际投资在带动中国经济迅速发展的同时,也不可避免地影响国内的资源环境形势。基于此,本文以中国为研究对象,探究对外直接投资对母国环境的影响及其作用机制,对于“一带一路”战略背景下中国改善生态环境质量、推动经济绿色发展,具有重要的现实意义。本文首先从经济规模扩张、产业结构转型以及技术水平增进等三个视角,构建起对外直接投资影响母国环境的理论框架,并提出相应研究假说。随后,基于中介效应法,构建动态面板模型,在核算各省综合污染指数基础上,结合省级面板数据与系统GMM估计方法,实证探究对外直接投资对母国环境的基本影响,并对其作用机制进行了检验、识别与分析。多个角度开展的稳健性检验依然表明实证结果是稳健的。研究结论如下:一是对外直接投资通过推动母国经济规模扩张,导致其污染物排放增加;二是对外直接投资通过促进母国产业结构朝向服务化转型,有利于减少其污染物排放;三是对外直接投资通过引致反向技术溢出效应,有利于母国污染物排放减少;四是综合来看,当前中国推动对外直接投资,有利于减少母国污染物排放。最后,本文从优化国际投资结构、强化技术领域国际合作等方面提出促进中国环境治理的政策建议。  相似文献   

17.
基于VAR模型的水资源利用与经济增长动态关系研究   总被引:2,自引:0,他引:2  
基于VAR模型,通过变量平稳性检验和协整分析,广义脉冲响应和预测方差分解分析,利用中国1980-2007年水资源利用和经济增长相关数据,对中国经济增长与水资源利用的长期均衡关系及其动态性进行了实证分析。研究结果表明:①经济增长与总用水量、工业用水量和生活用水量之间存在长期均衡关系,而农业用水与经济增长之间不存在长期均衡关系,这与研究期间中国处于工业化中期阶段的事实相吻合;②经济增长对水资源利用的冲击响应的滞后期短且是非渐进的,而水资源对经济增长产生显著影响的滞后期较长且是非渐进的,我国经济发展中工业用水、生活用水量增加趋势明显,农业用水量随着经济发展出现零增长和负增长;③经济增长对水资源利用的预测方差起着重要作用,而水资源利用对经济增长的预测方差的贡献度较小。建议加强工业用水和生活用水的节水措施,减少工业和生活用水量,实现水资源可持续利用。  相似文献   

18.
本文将社会选择理论引入到流域跨界水资源配置冲突的解决研究中,从群决策的角度寻找到流域内各区域一致同意的、满足水量分配公平的流域水资源配置方案。流域水资源配置冲突问题从表面上看是资源问题,实质上却是一个典型的决策问题。作为一种具有混合特性和稀缺性的自然资源,流域稀缺水资源的分配实质上是多主体参与的涉水利益分配,而分配的核心问题是如何通过合理的群决策机制协调水资源配置冲突中不同行政区域之间的利益关系进而实现公平。本文提出基于社会选择理论的流域跨界水资源配置冲突解决框架,首先从公平性角度将流域水资源配置冲突看成一个短缺资源的配置问题,利用P、AP、CEA和CEL四种破产准则获取可行的水量分配方案集合;其次运用社会选择理论中的PV、BC、HQ、PCM和FB五种偏好聚合方法进行流域内各行政区域个体偏好聚合的群决策分析;通过破产准则与偏好聚合的结合能够实现流域水资源配置冲突群决策结果的公平,所得流域水量分配方案易于被冲突主体所接受。最后,以华北缺水地区的漳河流域跨界水资源配置冲突问题为例进行研究,并比较不同破产准则及偏好聚合方法在解决流域跨界水资源配置冲突中的应用。研究结果表明,社会选择理论与破产准则的结合在解决流域跨界水资源配置冲突问题中具有较高的实用价值。  相似文献   

19.
One of the targets of the United Nations ‘Millennium Development Goals’ adopted in 2000 is to cut in half the number of people who are suffering from hunger between 1990 and 2015. However, crop yield growth has slowed down in much of the world because of declining investments in agricultural research, irrigation, and rural infrastructure and increasing water scarcity. New challenges to food security are posed by accelerated climatic change. Considerable uncertainties remain as to when, where and how climate change will affect agricultural production. Even less is known about how climate change might influence other aspects that determine food security, such as accessibility of food for various societal groups and the stability of food supply. This paper presents the likely impacts of thermal and hydrological stresses as a consequence of projected climate change in the future potential agriculture productivity in South Asia based on the crop simulation studies with a view to identify critical climate thresholds for sustained food productivity in the region. The study suggests that, on an aggregate level, there might not be a significant impact of global warming on food production of South Asia in the short term (<2°C; until 2020s), provided water for irrigation is available and agricultural pests could be kept under control. The increasing frequency of droughts and floods would, however, continue to seriously disrupt food supplies on year to year basis. In long term (2050s and beyond), productivity of Kharif crops would decline due to increased climate variability and pest incidence and virulence. Production of Rabi crops is likely to be more seriously threatened in response to 2°C warming. The net cereal production in South Asia is projected to decline at least between 4 and 10% under the most conservative climate change projections (a regional warming of 3°C) by the end of this century. In terms of the reference to UNFCCC Article 2 on dangerous anthropogenic (human-induced) interference with the climate system, the critical threshold for sustained food productivity in South Asia appears to be a rise in surface air temperature of ~2°C and a marginal decline in water availability for irrigation or decrease in rainfall during the cropping season.  相似文献   

20.
Economic values of water for the main Public Irrigation Schemes in the sub-middle region of the São Francisco River Basin, in northeastern Brazil, are determined in this study using an integration of a global agro-economic land and water use (MAgPIE) with a local economic model (Positive Mathematical Programming). As in the latter, the water values depend on the crops grown, and as Brazilian agriculture is strongly influenced by the global market, we used a regionalized version of the global model adapted to the region in order to simulate the crop land use, which is in turn determined by changes in global demand, trade barriers, and climate. The allocation of sugarcane and fruit crops projected with climate change by the global model, showed an impact on the average yields and on the water costs in the main schemes resulting in changes in the water values locally. The economic values for all schemes in the baseline year were higher than the water prices established for agricultural use in the basin. In the future, these water values will be higher in all the schemes. The highest water values currently and in the future were identified in municipalities with a significant proportion of area growing irrigated sugarcane. Being aware of current water values of each user in a baseline year and in a projected future under global climate and socioeconomic changes, decision makers should improve water allocation policies at local scale, in order to avoid conflicts and unsustainable development in the future.  相似文献   

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