Dealing with double-counting in tiered hybrid life-cycle inventories: a few comments

Strømman et al. (2009) developed a method for dealing with double-counting in tiered hybrid LCA. Their algorithms identify overlaps of physical and monetary flows in the process and input–output parts of their hybrid data base, and then remove double-counted monetary flows in the input–output system using structural path analysis. Strømman's adjustment criterion is that the set of input–output paths to be removed should have the same monetary value as the process system flow that it overlaps with. I comment on Strømman's methods with respect to the accuracy of the correspondence between process and input–output systems. I argue that the set of double-counted paths to be removed from the input–output system is better selected on the basis of sector definitions than monetary value.     

海河流域植物中碳的输出(或存留)量和土壤中的库存量

研究了海河流域地区植物中碳的输出量和土壤库存量。结果指出：不同作物－土壤系统中各种作物碳的输出量和归还量有很大不同,作物碳输出量一般为归还量的３－１７倍;海河流域地区不同子流域土壤中碳的库存量也有差异,以滹沱河子流域土壤碳的库存量最高,大清河子流域土壤中碳的库存量最低。     

粮食生产的投入产出影响因素分析——基于江苏省粮食生产的实证研究

在对江苏省13个市的粮食生产数据搜集整理的基础上，运用面板数据模型进行了投入产出的影响因素分析。结果显示，土地是影响目前江苏省粮食生产的最主要因素，因此随着城市化进程的不断加快，耕地面积的缩减，粮食产量有下降的趋势；此外，由于技术效率和劳动生产率的提高，出现了在劳动力投入不断下降条件下的粮食产量上升，但是二者表面上的反向关系不应当被简单理解为劳动力对产出弹性的负作用；在农资投入方面，化肥与农业机械动力的投入对于江苏省粮食生产有积极影响。     

A new and integrated hydro-economic accounting and analytical framework for water resources: a case study for North China

Water is a critical issue in China for a variety of reasons. China is poor of water resources with 2300m(3) of per capita availability, which is less than 13 of the world average. This is exacerbated by regional differences; e.g. North China's water availability is only about 271m(3) of per capita value, which is only 125 of the world's average. Furthermore, pollution contributes to water scarcity and is a major source for diseases, particularly for the poor. The Ministry of Hydrology [1997. China's Regional Water Bullets. Water Resource and Hydro-power Publishing House, Beijing, China] reports that about 65-80% of rivers in North China no longer support any economic activities. Previous studies have emphasized the amount of water withdrawn but rarely take water quality into consideration. The quality of the return flows usually changes; the water quality being lower than the water flows that entered the production process initially. It is especially important to measure the impacts of wastewater to the hydro-ecosystem. Thus, water consumption should not only account for the amount of water inputs but also the amount of water contaminated in the hydro-ecosystem by the discharged wastewater. In this paper we present a new accounting and analytical approach based on economic input-output modelling combined with a mass balanced hydrological model that links interactions in the economic system with interactions in the hydrological system. We thus follow the tradition of integrated economic-ecologic input-output modelling. Our hydro-economic accounting framework and analysis tool allows tracking water consumption on the input side, water pollution leaving the economic system and water flows passing through the hydrological system thus enabling us to deal with water resources of different qualities. Following this method, the results illustrate that North China requires 96% of its annual available water, including both water inputs for the economy and contaminated water that is ineligible for any uses.     

石家庄市主要农作物灌溉节水潜力研究

利用田间作物灌溉试验数据，对作物单产产量与需水量的关系进行了模拟，并据此以县域为单元，计算了1984～2001年石家庄市主要农作物冬小麦、夏玉米和棉花获得逐年实际产量的理论总需水量、理论灌溉总需水量、实际灌溉用水量，测算了3种作物灌溉节水的空间。结果表明，1984～2001a。按照节水高效试验所得的产量需水模式。获得石家庄市3种主要作物产量的理论需水总量为23-29亿m^3／a，理论灌溉需水总量为8．8-13．8亿m^3／a，实际灌溉用水量平均约为17亿m^3／a，农业年均超采地下水5．67亿m^3／a。按照目前的种植结构和产量水平，石家庄市今后作物灌溉节水的理论上限为9亿m^3／a。即使加大节水投入，实现最大节水潜力的一半。仍不能弥补目前地下水的超采量。在2010年实现南水北调，部分城市用水归还农业用水，且实现最大节水潜力的一半的情况下，水资源方能勉强维持平衡。因此，石家庄市今后应一方面加大农业节水投入和管理。另一方面，也应根据水资源承载力适当减少高耗水的冬小麦播种面积，同时全面建设节水型社会，方能实现可持续发展。     

煤矿事故中生命价值经济评价探讨

我国每年都有大量的煤矿事故发生 ,造成数千名矿工死亡 ,对死亡矿工的经济赔偿 ,往往是事故处理的一大难题 ,其主要原因是目前对死亡矿工的赔偿标准偏低。由于赔偿费用低 ,经济赔偿的代价不足 ,以引起威慑和警戒 ,部分煤矿企业仍然不重视安全生产、不珍惜矿工生命 ,从而煤矿伤亡事故不断发生。分析了目前国内外主要的生命价值评价方法和评价结果 ,对煤矿事故中的生命价值进行了研究 ,提出采用净产值推算矿工的生命价值 ,并给出了相应的计算公式和分析实例。分析结果表明 ,目前的赔偿标准不能体现矿工的生命价值 ,二者之间存在相当大的差距     

环境因子对某新型延时起爆装置性能影响研究

目的研究环境因子对某火工元件延时性能和输出能量的影响。方法根据某型延时起爆装置的组成结构特点,依据火工品试验法、军械装备环境试验法,结合极限使用环境条件设计了高温高湿、温度冲击试验。结果高温高湿的延迟时间范围为260~630 ms;温度冲击的延迟时间范围为283~513 ms,高温高湿输出能力范围为13~17 mm,温度冲击输出能力范围为13~18 mm。结论高温高湿试验对延迟时间影响较大,出现超出指标的延迟时间。     

Cardiac blood flow studies in fetuses with haemoglobin bart's disease

Blood flow across the atrioventricular valves and outflow tracts was measured in 55 normal fetuses and 32 fetuses with haemoglobin (Hb) Bart's disease between 18 and 26 weeks of gestation. The mean velocities remained unchanged in both normal and affected fetuses over the gestations studied. The volume flow across both atrioventricular valves and outflow tracts increased as the gestation advanced in both normal and affected fetuses, but was significantly higher in affected than in normal fetuses. The same magnitude of increased flow was found in both hydropic and non-hydropic fetuses with Hb Bart's disease. These findings suggest that fetuses with severe and long-standing anaemia have a remarkable cardiac compensatory mechanism for the maintenance of tissue oxygenation. In response to anaemia and circulatory loading, the cardiac chambers and outflow tracts enlarge proportionately up to twice the normal values. Because of this response and the operation of the Frank-Starling mechanism, the heart is able to maintain a normal mean velocity of propulsion and the net output is increased to two to three times that in normal fetuses. Hydropic changes in these anaemic fetuses appear unrelated to cardiac failure as cardiac failure is not observed at the time that hydropic changes develop.     

我国环保产业投入与产出的空间非均衡性分析

环保产业是我国七大战略性新兴产业之一,加快发展环保产业是促进发展方式转型、提高经济增长质量的重要举措.基于空间非均衡性理论与测算方法,通过构建环保产业投入与产出评价指标,计算了我国环保产业投入与产出的基尼系数,探究了东中西部环保产业投入与产出的空间差异.结果表明,在2000年、2004年和2011年3个时间点,我国环保产业投入水平的基尼系数处于0.3~0.4区间内,呈现出地区间均衡发展的趋势;环保产业产出水平的基尼系数分别为0.33、0.40和0.45,即我国环保产业产出水平的区域差异愈加明显,对经济增长的贡献逐渐呈现出不均衡态势;环保产业投资效率的空间非均衡性明显,2011年基尼系数甚至达到0.72,即投资效率的极不均衡状态.此外,我国东中西部地区在环保产业投入水平方面基本一致,东部和中部地区在环保产出水平方面明显优于西部地区,东部地区在投资效率方面遥遥领先其他区域.基于我国环保产业发展空间非均衡性的特点,提出了加快环保产业发展的政策建议:保持东部地区的环保投入力度,发掘中西部地区环保产业发展的新动力,充分利用产业发展的空间溢出效应等.      

Estimating the Unknown Components of Nutrient Mass Balances for Forestry Plantations in Mine Rehabilitation, Upper Hunter Valley, New South Wales, Australia

Commercial forestry plantations as a postmining land use in the Upper Hunter Valley of New South Wales, Australia are restricted by both the poor nutrient availability of mining substrates and low regional rainfall. An experiment was conducted to investigate whether municipal waste products and saline groundwater from coal mining operations could improve early tree growth without impacting on the environment through salt accumulation and/or nutrient enrichment and changes in groundwater quality. Potential impacts were investigated by quantifying the nutrient cycling dynamics within the plantation using an input–output mass balance approach for exchangeable calcium (Ca²⁺), exchangeable magnesium (Mg²⁺), exchangeable potassium (K⁺), exchangeable sodium (Na⁺), nitrogen (N), and phosphorus (P). Measured inputs to and outputs from the available nutrient pool in the 0–30 cm of the overburden subsystem were used to estimate the net effect of unmeasured inputs and outputs (termed “residuals”). Residual values in the mass balance of the irrigated treatments demonstrated large leaching losses of exchangeable Ca, Mg, K, and Na. Between 96% and 103% of Na applied in saline mine-water irrigation was leached below the 0–30-cm soil profile zone. The fate of these salts beyond 30 cm is unknown, but results suggest that irrigation with saline mine water had minimal impact on the substrate to 30 cm over the first 2 years since plantation establishment. Accumulations of N and P were detected for the substrate amendments, suggesting that organic amendments (particularly compost) retained the applied nutrients with very little associated losses, particularly through leaching.