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81.
Recognizing the socio-economic and biophysical causes of land degradation at the national level is important for cause-targeted strategies when designing policies for combating land degradation. This study aims to identify the biophysical and socio-economic factors that significantly affect land degradation across Vietnam and to interpret the causalities underlying the effects. The dependent variables considered in the study are spatial, the extent and intensity of degradation in three land-use zones (agriculture, forest and severely degraded abandonment). The hypothesized explanatory variables are common economic and demographic drivers and bio-physical factors such as soil, terrain constraints, and neighborhood land-use structures that are often neglected in many large-scale land degradation assessments. Instead of using a single inferential statistic technique, we used multi-linear regression and binary logistic regression in a complementary manner to increase the detectability and credibility of the degradation cause analyses. The results showed agricultural production growth had strong and consistent effects on land degradation extent and intensity. Population growth, especially in rural areas, had a strong effect on the extent of overall land degradation. The importance of a neighboring forest was revealed for its ability to reduce land degradation intensity in abandoned, unproductive lands. The concrete faceting of the causal analysis for each land-use zone as social–ecological stratum allowed us to combine the defined social–ecological contexts, contemporary theories, and hypotheses in the field to clarify the causal factors of a complex phenomenon like land degradation. The study demonstrates these contemporary inferential statistics can be complementarily used to sufficiently detect and understand land degradation causes at the national level. The results suggest implications for national land management policy: internalizing land degradation costs in the farming system evaluation for payment for ecosystem services policy, restricting forest conversion, and improving extension services and education in agrarian communities.  相似文献   
82.
This paper investigates the effects of microstructures and financial reforms on time-varying informational efficiency in an emerging equity market setting. Our data comprises of firm level data from the Trinidad and Tobago Stock Exchange, over the period 1990–2013. Using a dynamic panel regression framework while controlling for firm size, we find that microstructures, specifically liquidity, volatility, automation and the number of shareholders have an important role in influencing the time-varying efficiency of this emerging market. The financial reforms, namely liberalisation and regulation are not found to have a notable influence. We also consider heterogeneity at the firm level, finding that the microstructures of the banking firms listed in this market have a greater impact on market efficiency, in relation to the other listed firms.  相似文献   
83.
The present inquiry lays a groundwork for the analysis of the net greenhouse gas (GHG) footprint of oil in the oil-abundant settings. To address the research question, the study puts forward a three-sector decision model, which provides a common ground for the assessment of the interaction of the structuralist and institutional factors influencing environmental pollution in the oil-reliant economies. The study shows that fossil-fuel abundance triggers forces, which induce diametrically opposed effects concerning atmospheric pollution. These are the rising carbon-intensive oil extraction and processing and fossil-fueled power generation versus shrinkage of the carbon-intensive manufacturing and growth of the low-carbon tertiarization. The theoretical analysis enables compartmentalization of the essential factors, which determine GHG emissions in the respective countries. To assess the significance of the proposed theoretical framework, the study employs multivariate panel co-integration techniques and two-stage fixed effects estimations for a dataset of 38 oil-producing countries for the time period between 1960 and 2018. In contrast to the existing literature, this study drives apart from the black box approaches that employ just one omnibus variable, per capita income.  相似文献   
84.
85.
作为推动国民经济增长和促进社会稳定的基础力量,中小企业在市场中扮演着最活跃的经济主体。与大企业相比,中小企业有其鲜明的成长特征,从动态演进视角选取体量规模、生命周期、要素需求三个维度,系统探讨了中小企业的差异化特征。结论显示:体量规模特征反映在个体与群体以及经济板块之间;生命周期特征体现在死亡陷阱和空间格局演变上;要素需求特征会根据阶段创新内容的不同做出适时调整。  相似文献   
86.
Agricultural applications of nanotechnology are at a relatively early stage and little is known about consumer responses to the technology. Canadian consumer responses to food nanotechnology are examined through the lens of the Food Value Scale. Data from a survey of Canadian consumers are used to evaluate the relative importance of eleven food values to food purchase decisions. We find that taste, safety, nutrition, and price are among the most important food values to Canadians, however, consumers exhibit considerable heterogeneity with respect to the priority placed on these values. A discrete choice experiment (DCE) explores the effect of food values on choice behavior. The DCE is positioned as a sliced apple product with non-browning and antioxidant-enhanced features introduced through the use of nanocoating or a conventional coating method. Random parameters logit (RPL) and latent class models (LCM) confirm the existence of significant preference heterogeneity. The LCM identifies three classes of consumers: “supporters,” “doubters,” and “opponents” who differ in their reaction to nanotechnology and in the relative importance placed on food values such as naturalness, novelty, and convenience. The analysis shows that food values provide additional insights into consumers’ food choices and their attitudes toward novel food technologies.  相似文献   
87.
To improve the economies of scale in forest management and reduce the fragmentation of forestland, the Chinese central government has implemented a collective forest tenure supplementary reform since 2008. This has included a series of policies for motivating transfer of forestlands use rights among households in the country’s Southern Collective Forest Area (SCFA). However, to date there is little evidence that large-scale forest owners can earn more profits from timber harvests than small-scale forest owners in the SCFA. Using data collected from household surveys in the three of the SCFA’s provinces in 2016, this paper examines the return to scale of forestland ownership for timber harvests in this region, and how the scale of forestland ownership affects households’ profits from timber harvests. The results show a constant return to scale in timber harvests in the case provinces in China’s SCFA, that forestland area makes the most important contribution to the output of timber harvests, and that fragmentation of forestland results in lower profits from timber harvests. It appears that a moderate scale of forestland ownership should be identified for increasing the profits from timber harvests. With the rapid urbanization throughout China, an increase in off-farm employment among rural household members has a negative impact on timber harvests in the region. We argue that policymakers should realize the importance of encouraging the forestland transfers and improve the concentration of forestlands in the next stage of forest tenure rights reform in China’s SCFA.  相似文献   
88.
基础设施既可以作为特殊的资本存量直接促进经济增长,又可以通过促进投资和劳动力增加(增加生产要素数量)以及提高存量资本和劳动力的边际生产率(提高生产要素效率)间接促进经济增长。本文构建了一个扩展的Barro经济增长模型,并利用中国1992—2016年省级面板数据和中介效应模型对两条机制进行实证检验。结果发现:基础设施对经济增长具有促进作用,但对交通、能源、通信三类基础设施的影响以及在2008年金融危机前后均表现出异质性。直接效应呈动态上升趋势,中介效应则逐渐下降。针对异质性的原因,本文进一步采用非线性模型进行检验。结果表明我国基础设施对经济增长的促进作用主要表现为规模扩张型、数量型或外延型,而不是以质量型和内涵型为主的形式。能源和通信基础设施对经济增长的总效应具有规模效应,交通基础设施的规模效应不显著,但也对经济增长具有持续促进作用。这说明目前我国三类基础设施仍然具有较大投资潜力。其中的关键是要通过基础设施建设提高生产要素效率。  相似文献   
89.
We consider methods for estimating the means of survey variables in domains of a finite population, where sample sizes are too small to obtain reliable direct estimates. We construct generalized compositions from the direct and traditional design-based synthetic estimators and propose the methodology for evaluating their coefficients. This methodology measures similarities among sample elements and estimates of the domain means. We propose the compositions for two cases of auxiliary information: domain-level characteristics are available; true means of auxiliary variables are available for the estimation domains, and unit-level auxiliary vectors are known for the sample elements. In the simulation study, we show where the generalized compositions improve the traditional synthetic and composite estimators.  相似文献   
90.
For global sustainability it is imperative to find a balance across the three main components of sustainable development which are the economic, social and environmental aspects. However, it is not a simple task to make these contexts compatible, usually because of economic pressures which transform them into opposed objectives. This framework occurs across several dimensions within society and the economy, where the agricultural sector is not an exception. The objective of this study is to analyse the efficiency, total factor productivity and returns to scale in an economic, social and environmental perspective in farms of the European Union (EU) regions through Data Envelopment Analysis (DEA) approaches. The research concerning the returns to scale will be complemented by the Keynesian models. Data obtained from the European Union Farm Accountancy Data Network (FADN) was considered. The results show that in maintaining or improving the levels of production in farms, it is often possible to greatly reduce, in some cases, the consumption of fertilizers and crop protection products. On the other hand, from a social perspective, some European Union regions are more generous in the salaries paid to farming workers and absorb more labour, which in a European context of unemployment, may be an interesting way to realistically look at and be engaged in the agricultural planning in a sustainable way, founding a balanced trade-off among the economic, social and environmental dimensions.  相似文献   
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