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1.
This article postulates strong endogenous relationships in lower income countries between institutional quality, financial development and sustained economic growth. These associations were investigated using the vector-error correction model (VECM) and Granger causality method for a sample of 79 countries from 2005 to 2022. The findings show that (1) these variables reinforce each other in the short run. (2) In the long run, both institutional quality and financial development can fuel economic growth. (3) The positive effect of institutional quality on economic growth is greater than that of financial development. Policy implications of these findings are that careful attention should be paid to co-development policies to enhance the institutional quality and the financial system in these economies. Policies should also consider economic growth strategies to enable sustainable economic growth rates.  相似文献   
2.
利用2004—2015年列车实际运营数据,构建广义加权旅行时间模型,探究我国东北地区城市群可达性的空间分布特征。结果表明:①高铁开通后,东北地区城市群的可达性水平有较大程度的提高,地级市较为明显;空间上,提高较为明显的区域集中在铁路沿线以及辽中南城市群的部分城市。②高铁对东北地区第三产业集聚现象并不明显。③城市可达性水平的提高可以促进东北地区城市群经济增长,高铁的开通对于地区经济增长具有溢出效应。  相似文献   
3.
This paper examines long-run and short-run dynamics of renewable energy consumption on carbon dioxide (CO2) emissions and economic growth in the European Union. This study employs cointegration tests, Granger causality tests and vector error correction estimates to examine the direction of Granger causality, the long-run dynamics of economic growth and energy variables on carbon emissions. This study analyses time series data from the World Development Indicators over the period from1961 to 2012. The results of this study support a link between renewable energy consumption, economic growth, industrialization, exports and CO2 emissions in the long-run and short-run. The results support that the sign of the long-run dynamics from the endogenous variables to the CO2 emissions variable is negative and significant, which implies that the energy and environmental policies of the European Union aimed at curbing CO2 emissions must have been effective in the long-term. Furthermore, renewable energy consumption and exports have significant negative impact on CO2 emissions in the short-run. However, industrialization and economic growth have positive impact on CO2 emissions in the short-run. The results suggest that both economic growth and industrialization must have been achieved at the cost of harming the environment. The finding suggests that the increasing consumption of renewable energy tends to play an important role in curbing carbon emissions in the region.  相似文献   
4.
Cultural heritage does not have direct economic benefits. However, if properly managed it can stimulate social cohesions, improving the environment and have beneficial economic spin offs for the local communities. This paper discusses the role of communities in the formulation of the policies concerning their local environment. It argues that community engagement by policy makers is important in giving legitimacy and ownership of the policies. Furthermore, this paper discusses the potential of cultural heritage in diversifying the economy in Botswana. This paper recommends for the re-assessment of the relationship between the state and local communities which is critical in resuscitating the seemingly ailing community business organizations. In conclusion, it argues for the sustainable management of cultural heritage as a social and economic resource in the next 50 years of Botswana’s independence.  相似文献   
5.
This study examines the Granger causality relationships between economic growth, energy consumption and emissions, from 1980 to 2007 in Bahrain, controlling for capital and urban population using Toda and Yamamoto’s approach. It was found that there is unilateral causality which runs from urban population, economic growth, capital and energy consumption to environment. Further, we found strong support for causality running from economic growth to energy consumption, emissions and capital. The existence of these linkages suggests that the government of Bahrain may pursue energy efficiency strategies and carbon emissions reduction policy in the long run without impeding economic growth. Additionally, the long run pursuit of high economic growth given sustained increases in energy efficiency may also reduce CO2 emissions intensity per unit of her GDP.  相似文献   
6.
以水华鱼腥藻和四尾栅藻分别作为蓝藻,绿藻代表藻种,采用均匀设计实验方法(uniform design experimentation,UDE)设计藻类AGP实验。采用通径分析法(Path Analysis,PA)对氮、磷、铁和锰在不同藻种增殖过程中的影响程度进行分析。结果表明,4种营养元素对水华鱼腥藻增殖影响的决策排序为FeTNTPMn,微量金属元素铁是影响水华鱼腥藻(蓝藻)增殖的主要因素;对四尾栅藻增殖影响的决策排序为TNTPFeMn,常量元素是影响四尾栅藻(绿藻)增殖的主要因素。联合通径分析法和逐步二次方回归分析法(QRA)建立的数学模型,可用于预判藻增殖。  相似文献   
7.
基于环境卫星CCD数据的黄海浒苔遥感监测   总被引:1,自引:1,他引:0  
2007年以来,黄海海域每年夏季都发生大面积浒苔绿藻潮,影响沿岸人民的生活、生产。考虑到其分布范围动则几千、上万平方公里,水面监测很难实施,尝试利用遥感技术对其分布和发展变化情况进行监测。基于中国自主产权的环境卫星(HJ1)数据,采用经典植被指数算法和人工辅助判读方法,对2013年黄海浒苔暴发全过程进行了连续遥感监测,分析了此次浒苔过程的分布和漂移路线。监测结果表明,浒苔绿藻潮首发于江苏盐城东部海域,由南向北逐渐漂移,面积逐渐扩大,结束于青岛东北部海域;该期间,浒苔最大覆盖面积达663.54平方公里。  相似文献   
8.
Effects of controlled nutrient additions on a prairie stream were studied using a before‐after‐control‐impact paired design. The site is in a reference condition with low soluble nitrate (NO3) and phosphate (soluble reactive phosphorus [SRP]) in summer (3 μg NO3‐N/L, 4 μg SRP/L). Nutrients were added to two reaches over the growing season at two levels (Low Dose — 39 μg NO3‐N/L and 4.4 SRP/L; High Dose — 119 μg NO3‐N/L and 15.6 μg SRP/L). Continuously measured dissolved oxygen (DO) and changes in aquatic flora were compared to an upstream Control. Enrichment led microalgae and filamentous algae to increase in density, areal coverage, and thickness, and the magnitude of the changes were largely concordant with dosing (more in the High Dose); algal growth also suppressed macrophytes in the High Dose. Enrichment caused significant increases in diel DO swings whose magnitudes were consistent with dosing level. In the High Dose, benthic algae flourished in the growing season and then senesced en masse in fall. The decomposing algae led DO to crash (ca. 0 mg/L on the bottom), but DO impacts were out‐of‐sync with peak algal growth and photosynthesis, which occurred weeks earlier. This finding provides a plausible explanation as to why high DO delta in streams impacts aquatic life even when concurrently measured DO is not low. When DO crashed, DO was longitudinally patchy, some areas having low DO near the bottom, others near saturation. Geomorphology and exposure to wind may have caused this pattern.  相似文献   
9.
本文以江苏省为研究区域,采用1990—2013年江苏省市级面板数据,基于单位根检验和面板协整检验,运用可拓展的随机性环境影响评估模型(STIRPAT)和参数、半参数固定效应回归方法,对经济增长与工业COD排放之间的关系展开研究。研究发现,江苏省经济增长与工业COD排放之间存在倒U形曲线关系,即全省工业COD排放随经济的发展呈现先增长后降低的趋势,同时人口增长对水污染物排放影响很大,二者之间的环境库兹涅茨曲线表明了经济持续发展能够协调并能解决其与水污染排放之间的困境。本研究丰富了社会经济发展与水污染关系在市级尺度层面的实证研究,为"十三五"期间江苏省水污染治理提供了政策依据。  相似文献   
10.
Nitrogen and phosphorus criteria were developed for 233 km of the Yellowstone River, one of the first cases where a mechanistic model has been used to derive large river numeric nutrient criteria. A water quality model and a companion model which simulates lateral algal biomass across transects were used to simulate effects of increasing nutrients on five variables (dissolved oxygen, total organic carbon, total dissolved gas, pH, and benthic algal biomass in depths ≤1 m). Incremental increases in nutrients were evaluated relative to their impact on predefined thresholds for each variable; the first variable to exceed a threshold set the nutrient criteria. Simulations were made at a low flow, the 14Q5 (lowest average 14 consecutive day flow, July‐September, recurring one in five years), which was derived using benthic algae growth curves and EPA guidance on excursion frequency. An extant climate dataset with an annual recurrence was used, and tributary water quality and flows were coincident with the river's 10 lowest flow years. The river had different sensitivities to nutrients longitudinally, pH being the most sensitive variable in the upstream reach and algal biomass in the lower. Model‐based criteria for the Yellowstone River are as follows: between the Bighorn and Powder river confluences, 55 μg TP/l and 655 μg TN/l; from the Powder River confluence to Montana state line, 95 μg TP/l and 815 μg TN/l. Pros and cons of using steady‐state models to derive river nutrient criteria are discussed.  相似文献   
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