来安县气候多尺度时间变化特征及其对气候生产力的影响

文章利用来安县国家气象站1961—2015年温度和降水资料,采用Thornthwaite Memorial模型计算气候生产力,分析来安县近55年温度和降水气候因子的时空变化特征,研究气候变化对来安气候生产力的影响,得出结论:近55年来安升温趋势显著,升温幅度0.23℃/10a,此趋势是一突变现象,具体突变点是2001年。降水量呈波动上升趋势,波动幅度大,最大波动幅度高达1 230 mm。年平均气温和降水量在年际尺度上周期振荡以准4～8a为主,年代际尺度上周期信号以准16a为主;近55年来安气候生产力上升趋势显著,上升幅度每10年20 kg·km-2,此上升趋势是一突变现象,具体突变点是1995年。气候生产力在年际尺度上周期振荡以准8a左右为主,年代际尺度上周期信号以准16a为主;气候生产力同时受气温、降水影响,气候变化对气候生产力的提高有利,但只在水分充足条件下,其提高幅度才更大,未来"暖湿型"变化趋势使来安气候生产力的上升空间在10%左右。     

青藏高原青南和甘南牧区气候变化趋势及对环境和牧草生长的影响

对 2 0世纪 80年代以来青藏高原青南牧区和甘南牧区气候变化的统计分析表明 ,该地区呈现出气温升高和降水量减少的明显趋势。气候暖干化 ,造成该地区干旱缺水 ,草地退化、沙化和鼠害猖獗 ,使草畜矛盾不断加剧 ,已严重威胁到牧区的生存和发展 ,也影响到长江、黄河中下游地区的可持续发展 ,对此应予高度重视 ,同时应采取针对性政策措施 ,加大对青藏高原江河源头和上游地区生态环境的恢复性治理和保护。     

基于改进三维生态足迹模型的上海市生态足迹动态研究

生态足迹是评估可持续发展的重要方法,本文采用改进后的三维生态足迹模型对上海市2000-2014年的生态足迹进行动态研究。结果表明,2000-2014年,上海市人均生态足迹、承载力以及赤字均呈下降的趋势,而总生态足迹、承载力以及赤字则呈上升的趋势;化石能源的足迹变化对上海市足迹变化起决定作用,是上海市生态赤字的重要驱动力;人均生态足迹广度呈下降的趋势,略有波动,而人均生态足迹深度呈上升的趋势,波动较大,反映出生态压力逐渐增大。研究结果为上海市可持续发展的决策提供科学依据。     

2005年能源需求增速将回落供求状况趋于好转

2004年能源生产快速增长，需求十分旺盛，主要能源产品进口大幅增加，出口明显减少，能源价格大幅攀升。2005年能源需求增速将有所回落，能源供求形势将比2004年有较大缓解。预计全年发电量同比增长12％左右，煤炭产量同比增长8．5％左右，成品油表观消费量同比增长10％左右。预计煤炭和电力价格仍呈上升趋势，国际油价波动幅度将有所放缓。建议推进能源价格形成机制改革，建立和逐步完善能源产品储备制度，重视高耗能产品的国际贸易。     

乳源1965—2022年汛期降水的时空特征

根据乳源国家气象观测站1965—2022年和13个区域自动气象站2014—2022年的降水资料,采用滑动t检验、Morlet小波分析等方法分析近58 a乳源降水的时空变化特征。结果表明：乳源年均降水量呈单峰型,峰值出现在5月和6月;乳源汛期降水量总体是较为明显增加的趋势,存在6、15、34 a 3个振荡周期,34 a周期是汛期降水量变化的第一主振荡周期;汛期降水量的变化趋势和年降水量的变化趋势基本一致;乳源汛期降水的空间分布总体呈现自西南向东北递减的趋势。     

就业结构演变:三产将成为吸纳从业人员主力

一、从产业角度考察我国就业结构的变动改革以来,与我国经济的快速发展和三次产业国内生产总值份额的变化相对应,三次产业从业人员数与份额也发生了较大的变化。第一产业从业人员数量与份额呈下降趋势,从业人员份额已由1978年的2/3强下降到目前的1/2左右。第二产业从业人员数量及份额呈上升趋势,但是20世纪90年代后期从业人员数量及份额     

中国城市房价周期波动特征——以北京、上海、广州与深圳为例

本文研究北京、上海、广州与深圳四大城市的住房价格(以下简称房价)周期波动特征。通过使用四大城市从1991年一季度(1993年二季度)至2010年一季度的房价指数数据,本文考察了上述城市房价的长期趋势与短期波动。本文的主要发现包括:(1)古典周期特征方面,四大城市房价都经历了一个完整周期,本轮周期正在形成中。(2)现代周期特征方面,四大城市真实房价趋势成分主要表现出从20世纪90年代初开始下降及21世纪初开始至2010年一季度的上涨趋势。四大城市房价周期成分表现出明显的波动性、持续性和对称性,仅有广州和深圳的房价波动存在顺周期的同期协动性。此外,1998年住房制度市场化改革后,四大城市房价周期成分的波动性、持续性和协动性特征均发生了明显变化。     

西安市降水时空变化特征及突变分析

根据西安市1975~2012年4个典型气象站点的降水资料,运用空间插值法、累积距平曲线法、Mann-Kendall(M-K)检验法以及双累积曲线法等多种方法对西安城区和郊区年际、季节和汛枯期降水时空变化特征进行了趋势分析和突变检验。结果表明:(1)近38年来西安地区多年平均降水量为611.5mm,总体上呈下降趋势,下降率为-13.7mm/10a,且市区降水量下降趋势较郊区显著;(2)无论是枯季还是汛期,城区降水量明显小于郊区,且两者呈现相反的变化趋势,这主要与城乡气候差异及人为因素有关;(3)年降水量突变点为1979年,而春、夏、秋、冬各季突变点分别为2000、1979、1980和1997年,与全年突变点不尽一致,汛期较枯季易发生突变;(4)从空间上来看,西安地区多年平均降水量由东南向西北呈递减趋势。     

陕西省土地市场价格时空变化规律研究

基于2008~2015年陕西省一级土地市场监测数据,运用地价指数趋势图来反映土地价格的时序变化。通过ArcGIS的空间分析功能对不同年土地市场的价格进行叠加分析,得到陕西省土地市场价格变化的时空分布规律。研究显示:陕西省2008~2015年商业地价和住宅地价变化波动较大,工业地价的变化相对平稳,三种地价变化总体呈上升趋势。以2008年作为基期,陕西省商业、住宅、工业地价的变化趋势均符合周期为2的移动平均变化趋势。2008~2015年关中地区、陕南地区的商业地价整体呈上升趋势、陕北地区相反;关中地区住宅地价的变化趋势性相对稳定、普遍呈上升趋势;除榆林市以外工业地价的整体变化趋势较稳定。     

产业链视角下稀土授权专利的文献计量分析——基于2000—2021年智慧芽数据

基于2000—2021年智慧芽数据库收录的稀土产业链有关专利数据,利用社会网络分析方法和Gephi软件的可视化分析,从稀土产业链的开采、冶炼、精加工以及应用4个环节分析稀土专利技术趋势,为稀土技术发展提供借鉴。结果表明：从时间趋势来看,总体呈上升趋势,但稀土冶炼环节专利数量波动较大,稀土开采与精加工环节增长缓慢;从专利授权机构来看,江西理工大学、江西稀土金属钨业有限公司在采矿阶段专利授权量排名靠前,主要集中于矿产资源附近,而其他环节主要以日本、韩国和德国的机构为主;从专利授权机构合作网络来看,发现国外的公司与机构之间合作密切,而中国科研院所间缺乏协作;从热点技术领域来看,C22C59/00、C22C38/00、H01F/057、H01F41/02、B22F1/00等技术领域密度较大且处于核心位置。     

A Ricardian analysis of the economic impact of climate change on agriculture: Evidence from the farms in the central highlands of Afghanistan

This paper provides evidence on the economic impact of climate change on agriculture in the Central Highlands of Afghanistan by exploring the climate sensitivity of crop net revenue per unit of land. A Ricardian model and a novel 2017 dataset for 1502 farmers in three central provinces along with 34 years of weather information are used to study the impact of variations in seasonal precipitation and annual temperature. The findings suggest a significant and nonlinear effect of climate factors on crop net revenue. The impact of seasonal precipitation is found to vary across space and time. The effect of increased annual temperature is found to be generally positive and significant—both statistically and economically. The predicted impact of future climate change is largely beneficial, mainly due to warming.     

安太堡煤矿复垦区刺槐径向生长对气候因子的响应

在全球变暖的背景下,区域干旱化程度加强,严重限制了干旱和半干旱地区树木的生长。安太堡矿区位于我国农牧交错带,生态环境脆弱,对气候变化敏感。通过树木年代学研究方法,建立了安太堡煤矿复垦区人工刺槐林（Robinia pseudoacacia）的树轮宽度标准年表,树轮气候响应分析发现水分是限制研究区刺槐生长的主要因素,上一年9月至当年8月的水文年降水以及主要生长季（6～8月）的降水对树木的生长有重要的促进作用,但是当年9月降水有限制作用;生长季前冬季（12月、1月）的较高的温度也是限制刺槐径向生长的重要因素。     

Human capital and growth in Japan: Converging to the steady state in a 1% world

Annual growth in GDP/adult in Japan has declined from over 10% in 1969 to an average of 1% since the financial crisis in 1991. I show that a dynamic Solow growth model, augmented with human capital, weekly hours worked, and oil prices, explains Japan’s annual growth rates from 1969 to 2007 as conditional convergence to a steady-state rate of 1%/year. Each year of average adult schooling attainment raised GDP/adult directly or indirectly by 20 percent, and weekly hours worked had an output elasticity of 0.5. The marginal product of schooling in 2005 is double the marginal product of physical capital.     

Potential Impact of Climate Change and Armed Conflict on Inequality in Sub-Saharan Africa

This study investigates the potential impact of climate change and armed conflict on inequality in Sub-Saharan Africa (SSA). The system-GMM for a panel of 35 SSA countries is employed using annual data from 1997 to 2018. The empirical results indicate that armed conflict and climate are major drivers of inequality in SSA. The direct impact of the two determinants is more than the indirect impact. Also, the impact of armed conflict is more than the climate change. The coefficients of population growth, output growth, unemployment, natural rent, exchange rate and inflation rate are significant positive predictors of inequality in the SSA. The study advocates for a multidisciplinary inclusive growth strategy that prioritises the climate change reversal, de-escalation of armed conflict, population control, reduction of the unemployment rate and increasing informal sector productivity, to promote inclusive growth and reduce inequality. However, sequencing the policy targets relative to the magnitude of their impact on inequality is extremely crucial.     

Income polarization in China: Trends and changes

This paper estimates income polarization in China from 1978 to 2010 and decomposes the estimated polarization by population subgroups. In addition, a framework is proposed to disentangle a change in polarization into a growth and a redistribution component. This framework is then used to quantify the contributions of various income sources to a rise in polarization in China between 2002 and 2007. The analytical results suggest that (1) income polarization exhibited a broadly increasing trend from 1978 to 2010; (2) income polarization was large and rising among rural citizens, while low and declining among urban citizens; polarization of migrants also declined; (3) geographically, income polarization rose in east and particularly central China, while west China was most polarized with little change over time; and (4) the rise in polarization between 2002 and 2007 was mainly driven by the investment income, followed by transfers. Conversely, business income is polarization-reducing, especially in rural China. To a lesser extent, wage is also polarization-reducing, especially among migrants.     

江苏旅游业发展效率及对策研究——基于超效率DEA和Malmquist指数分析

文章利用超效率DEA模型和Malmqulst指数模型分别测算了江苏13市2001-2012年旅游业发展的静态效率与动态效率。结果显示:江苏旅游业静态效率保持先降后升的态势,从2001年的0.848下降到2006年的0.611,后又上升到2012年的0.824,12年间效率均值为0.726。各市旅游业效率存在显著的地区差异,且呈现逐步扩大的趋势。江苏旅游业动态效率(TFP)年均变化值-0.6%,增长主要来源于技术进步而不是规模效率的作用。在以上研究的基础上,提出提升江苏旅游业效率的对策,为旅游业持续、高效、健康发展提供理论参考。     

The productivity impacts of energy efficiency programs in developing countries: Evidence from iron and steel firms in China

We study the impact of a national energy efficiency program on total factor productivity (TFP) growth in firms in China's iron and steel industry. Using detailed firm-level survey data and multiple approaches to estimate program effects, we find participating firms experienced greater annualized TFP change. Our base specification estimates the program increased annual TFP growth by 3.1 percentage points, implying an annual private benefit of 148.7 million RMB/year per firm, with approximately equal contributions from technical change and scale efficiency change. Our results suggest that firms undervalued energy efficiency investments prior to the start of the program.     

Demographic change,human capital,and economic growth in Korea

We construct a measure of human capital using micro datasets on labor composition of age, gender, education, and wage rate and analyze its role in economic growth for the Korean economy. Over the past three decades, human capital has grown steadily at about 1% per year, contrasting to a continuously declining trend of total work-hours. This growth has been driven by the rise of better-educated baby-boom cohorts. A growth accounting exercise shows that human capital contributes significantly to economic growth; it accounted for 0.5% points of annual GDP growth over the period. Human capital is projected to remain a major growth factor over the next two decades as the increase in educational attainment continues. Increased employment rate of elderly or female workers reduces the aggregate human capital growth while increasing the available labor. Polices to improve human capital of female or elderly workers help to increase aggregate human capital growth.     

Saving not Spending: Indonesia’s Domestic Demand Problem

Indonesian income per capita has risen rapidly in the past 10 years. The growth in income, combined with an expanding middle class, has corresponded with strong growth in retail sales. Recently, however, this trend has started to change. Consumption growth has been relatively stable, but retail sales are growing more slowly than in the past. In order to develop a clearer picture of consumer spending in Indonesia, we discuss differences in spending behaviour across two income groups—lower-middle income and upper-high income. Consumption varies across income groups, so saving and investment patterns may also vary. We find that the upper-high income group, despite having more income than in the past, is less willing to invest and borrow than previously, and that the lower-middle income group continues to suffer from a lack of purchasing power. Meanwhile, investors are simply postponing investments, preferring to take a ‘wait and see’ approach. Excess saving can be economically problematic. If effective demand is too weak, it can have negative consequences for long-term economic growth. We begin, however, by surveying recent economic developments in Indonesia, focusing on the third quarter of 2017. Indonesia’s current rate of economic growth (5.1% year on year) places it among the world’s fastest-growing large economies, but the lack of acceleration is a concern: growth has not exceeded 6.0% since the second quarter of 2012. Despite this lack of acceleration, Indonesia has achieved macroeconomic and financial stability. The balance of payments has been improving since early 2016, with a narrow current account deficit—well below 3.0% of GDP—and a surplus trade balance. Exports grew by 17.3% in the third quarter of 2017, owing to rising commodity prices (which boosted export growth in both value and volume), while imports grew by 15.1%, although the impact on economic growth has so far been more moderate than in the commodity boom of 2000–2011. The growth in commodity exports has also benefited Kalimantan, Sumatra, and other commodity-rich regions. However, rising commodity prices come with some caveats. They might boost growth for a short period, but they raise the challenge of making this growth sustainable. We have seen this many times in the past. Increasing institutional capacity to better implement policy initiatives, for one, will help to deliver sustainable, high-quality economic growth.