Distribution of total mercury and methylmercury in lake sediments in Arctic Ny-Ålesund

The toxicities and bioavailabilities of total mercury (THg) and methylmercury (MeHg) in aquatic systems have made them the subjects of recent research. In this study, we collected a lake sediment core from Ny-Ålesund in Svalbard and analyzed the distributions of THg and MeHg in the sediments. The increased trend of THg was caused by anthropogenic contamination since the 14th century through long-range transportation, especially after the industrial era. However, the peak values of Hg in surface sediment samples could be explained by the increased algal scavenging process in recent decades. All the biogeochemical proxies (e.g., pigments and diatom biomass) revealed recent sharp increases in aquatic primary production due to the current climate warming. Rock-Eval analyses indicated that algal-derived organic matter took up a large portion, and quantitative calculation showed that 89.6-95.8% of the Hg in post-1950 could be explained by scavenging. The distribution of MeHg has a close relationship with total Hg and organic matter. The oxidation-reduction condition is one of the possible factors affecting the methylation rates in H2 lake sediments. Higher algal productivity and organic matter actually led to the increased trend of methylation in the uppermost sediment. This study supports some new key hypotheses on climate-driven factors affecting Hg and MeHg cycling in High Arctic lake sediments.     

Can environmental regulation promote industrial innovation and productivity?Based on the strong and weak Porter hypothesis

This paper constructed extended CDM model to study the effects of environmental regulation on industrial innovation and productivity based on the perspective of strong and weak “Porter hypothesis”, by using 28 manufacturing industry panel data of 2003–2014. The findings reveal that: (1) the impact of environmental regulation on R&D intensity lags behind. In the long run, environmental regulation intensity has a significant role in promoting R&D investment in manufacturing industry. (2) The R&D has a significant role in promoting the substantial innovation of manufacturing industry, and has a strong lag and continuity. However, the R&D intensity has no obvious effect on strategic innovation of manufacturing industry. (3) The substantial innovation doesn’t significantly promote the economic performance of manufacturing industry, but it has a significant role in promoting the energy performance of manufacturing industry, and the substantial innovation plays a significant role in promoting environmental performance in the long term. The strategic innovation significantly promotes the economic performance of manufacturing industry, and it inhibits the energy performance and has no significant effect on environmental performance in the short term. It can promote the energy performance of manufacturing industry, but significantly inhibit environmental performance in the long term. (4) Environmental regulation has significantly suppressed the substantive innovation and strategic innovation of manufacturing industry, and the weak Porter hypothesis has not yet been supported. In the short term, environmental regulation inhibits manufacturing economic performance, but it can promote energy and environmental performance. In the long run, environmental regulation promotes the economic and energy performance of manufacturing industry, but it inhibits environmental performance. The establishment of strong Porter hypothesis has a certain scenario.     

Do water saving technologies save water? Empirical evidence from North China

This paper describes the extent of water saving technologies usage and evaluates their impacts on water use, water productivity, total irrigated sown area and crop mix in North China. A set of panel data collected at the househol.d and plot levels is used in empirical analysis. Water saving technologies are categorized into traditional technologies, household-based technologies and community-based technologies. By 2007, traditional technologies and household-based technologies are used in almost all sample villages. However, the shares of sown area on which water saving technologies are used are still fairly low. Econometric analysis using plot level fixed effects show that using water saving technologies can reduce crop water use and improve the productivity of water. The positive effects are generated mainly through the use of household-based or community-based technologies. The use of water saving technologies does not have statistically significant impacts on total irrigated sown area and crop mix.     

Environmental policies and productivity growth: Evidence across industries and firms

This paper investigates the impact of changes in environmental policy stringency on industry- and firm-level productivity growth in a panel of OECD countries. To test the strong version of the Porter Hypothesis (PH), we extend a neo-Schumpeterian productivity model to allow for effects of environmental policies. We use a new environmental policy stringency (EPS) index and let the effect of countries׳ environmental policies vary with the pollution intensity of the industry and with the countries’ and firms’ technological advancement. A tightening of environmental policy is associated with a short-term increase in industry-level productivity growth in the most technologically-advanced countries. This effect diminishes with the distance to the global productivity frontier, eventually becoming insignificant. For the average firm, no evidence of PH is found. However, the most productive firms see a temporary boost in productivity growth, while the less productive ones experience a productivity slowdown.     

生产性公共支出、空间溢出效应与区域经济差距——基于多地区动态一般均衡模型的分析

改革开放以来,中国东、中、西部地区经济差距不断拉大,政府为协调区域经济发展水平,逐渐将生产性公共支出向较不发达的中部和西部地区倾斜。为了全面地评估这种财政政策的效果,在传统一般均衡分析的基础上将生产性公共支出及其空间溢出纳入宏观经济分析框架,构建了一个多地区动态一般均衡模型,并用该模型模拟了现实经济中区域生产性公共支出政策及其调整对区域经济和宏观经济的冲击,得到的结论是:(1)当前生产性公共支出空间分布基础上,新增生产性公共支出分散于各个地区,会继续扩大区域经济差距;(2)新增生产性公共支出集中于较不发达的地区时,由于较低的基础设施边际生产力和较弱的空间溢出效应,全国人均产出不能达到最大水平,但可缩小区域经济差距;(3)新增生产性公共支出集中于较发达的地区时,由于较高的基础设施边际生产力和较强的空间溢出效应,全国人均产出可达到最大水平,但同时拉大区域经济差距。由此得到的政策启示是:在现有生产性公共支出的区域分布基础上,以缩小区域经济差距为目标的次优的财政政策将新增的生产性公共支出向西部和中部等较不发达地区倾斜,靠直接刺激效应促进当地产出增长;以效率优先为准则的财政政策选取较发达地区为生产性公共支出目的地,因为较发达地区通常具有较高的基础设施边际生产力和较强的空间溢出效应。     

Crop biodiversity,productivity and production risk: Panel data micro‐evidence from Ethiopia

This paper uses data from the Central Highlands of Ethiopia to assess the productivity and production risk impacts of crop diversification. Using count index as a measure of crop biodiversity, results show that increasing crop biodiversity contributes positively to farm level productivity. In addition, the findings suggest that the level of production risk significantly responds to the level of diversity, with the effect highly conditional on the skewness. The major contribution of the paper is that, unlike previous similar studies that tended to focus on intra‐crop diversity, it incorporates the mutual interdependencies across crops within a farm by focusing on inter‐crop diversity. Hence the study adds to the growing empirical literature, particularly in Africa, that tests empirical relationships between productivity, risk and crop diversity. An important policy implication for a diversity rich country such as Ethiopia is that agro‐biodiversity can be used to improve agricultural productivity while promoting in situ conservation.     

资源型城市转型升级:压力测算与方向选择

在绿色增长理念和“分类引导、特色发展”的指导原则下,如何科学地识别资源型城市经济可持续增长的压力,从而确定未来转型升级方向,是引导资源型城市摆脱传统发展模式的关键。本文在绿色增长的理论框架下构建了资源型城市转型升级的能源节约、附加值提升和环境友好三维空间,从方向向量内生化、引入相对距离和外生权重三个方面对方向距离函数加以改进,提出资源型城市转型升级压力的测算方法,讨论了经济可持续发展的方向选择问题,进而以2008—2016年中国283个城市(包括115个资源型城市和168个非资源型城市)为样本进行了实证检验。结果发现:①资源型城市的绿色全要素生产率水平在0.4~0.5区间内,明显低于非资源型城市;②根据修正后的转型升级压力测算结果,考虑能源和环境因素后资源型城市转型升级压力巨大,80%以上处于中效区和低效区,49个城市选择单向转型,53个城市选择多向转型;③来自不同地理区位和成长阶段的测算结果表明,东部资源型城市的绿色生产率水平最高,东北地区要致力于附加值提升和节约能源,衰退型资源型城市应选择多向转型,不同主导资源型产业的城市则需因地制宜,选择差异化的转型升级策略。     

Refining the ecological footprint

Ecological footprint measures how much of the biosphere’s annual regenerative capacity is required to renew the natural resources used by a defined population in a given year. Ecological footprint analysis (EFA) compares the footprint with biocapacity. When a population’s footprint is greater than biocapacity it is reported to be engaging in ecological overshoot. Recent estimates show that humanity’s footprint exceeds Earth’s biocapacity by 23%. Despite increasing popularity of EFA, definitional, theoretical, and methodological issues hinder more widespread scientific acceptance and use in policy settings. Of particular concern is how EFA is defined and what it actually measures, exclusion of open oceans and less productive lands from biocapacity accounts, failure to allocate space for other species, use of agricultural productivity potential as the basis for equivalence factors (EQF), how the global carbon budget is allocated, and failure to capture unsustainable use of aquatic or terrestrial ecosystems. This article clarifies the definition of EFA and proposes several methodological and theoretical refinements. Our new approach includes the entire surface of the Earth in biocapacity, allocates space for other species, changes the basis of EQF to net primary productivity (NPP), reallocates the carbon budget, and reports carbon sequestration biocapacity. We apply the new approach to footprint accounts for 138 countries and compare our results with output from the standard model. We find humanity’s global footprint and ecological overshoot to be substantially greater, and suggest the new approach is an important step toward making EFA a more accurate and meaningful sustainability assessment tool.

四川省农业生产环境因素-化肥施用状况宏观分析

本文首次提出“区域化肥施用负荷”、“化肥施用相对生产力”、“化肥施用相对适宜度”等概念及研究方法,用于四川省化肥施用状况宏观分析。四川全省化肥施用量F=228．86kg／hm^2,全省21个市州中自贡、攀枝花、德阳、绵阳、遂宁、眉山、雅安和巴中等8个市F〉250kg／hm^2,其中攀枝花市达到457kg／hm^2;全省5个农业区中,成都平原区F值最高,达285．63kg／hm^2。四川省化肥施用负荷H=4704kg／km^2,自贡、德阳、遂宁、内江等4市H值是全省H值4倍以上,自贡、遂宁2市甚至达5倍以上;成都平原区、盆地丘陵区H值分别是17491kg／km^2和16309kg／km^2,远远高于其他地区。全省化肥施用相对生产力R=20．26kg,攀枝花市R=12．11kg,是全省最低的;盆地丘陵区R=20．16kg,其余地区R值均高于全省的。全省近10年平均化肥施用相对适宜度T=3．19作为评价基准,攀枝花市T=5．22,是全省最高的,属化肥施用高度过量;各农业区中,盆地丘陵区T=3．47,盆周山地区T=3．28,属化肥施用轻度过量,其余地区基本适宜。     

Carbon productivity convergence club and its initial conditions: China’s construction industry

A three-stage method is proposed to study the convergence clubs for the dynamic total factor carbon productivity (DCP) and the initial conditions. The first stage is to measure the DCP that reflects the initial difference. The second stage is to identify the convergence club of DCP. The last stage is to examine the initial factors that may affect the formation of the convergence club. Construction industry data from 30 provinces in mainland China from 2005 to 2016 were adopted to conduct an empirical study. The empirical results showed that (1) the arithmetic mean value of China’s provincial DCP showed an upward trend and the standard deviation showed an expanding trend. (2) There are five convergence clubs, but 13 provinces failed to converge to any club. (3) The higher the degree of construction industry marketization in 2005, the greater the probability that the provinces belong to a club with higher DCP. To improve the DCP, the effective diffusion of low-carbon construction technologies and the market-oriented reform of state-owned construction companies should be promoted. The three-stage method can also be applied to study different industries in different countries or regions.