面源污染视角下江西省耕地利用效率研究

[目的]在面源污染视角下考察耕地利用效率,可以为推动耕地可持续利用提供理论和参考依据。[方法]文章基于2000—2014年我国13个粮食主产省(区)耕地投入产出的面板数据,运用SBM方向性距离函数将耕地面源污染因素纳入到传统的效率分析框架,从省际比较的维度对江西省耕地利用效率进行了测度与分析。[结果]考虑面源污染因素对耕地利用效率测算产生了一定的影响;江西省耕地利用效率值呈现阶段性特征,耕地利用效率排名比较稳定,近年来排名有上升趋势;江西省耕地利用绩效一般,且与最佳实践者存在较大的差距。[结论]忽视面源污染因素的耕地利用效率评估是失真和不符合实际的,宜将面源污染因素纳入到耕地利用效率的测度框架,以此来更科学地量化评估耕地利用绩效;设计和完善相关政策,以有效控制耕地面源污染;加强与先进省(区)的交流与合作,学习其农业可持续耕作技术与管理经验,进一步推动江西省耕地产出与资源、环境协调发展。     

Transboundary pollution externalities: Think globally,act locally?

We analyze the implications of transboundary pollution externalities on environmental policymaking in a spatial setting, in which pollution diffuses across the global spatial economy independently of the specific location in which it is originally generated. This framework gives rise to a simple regional optimal pollution control problem allowing us to compare the global and local solutions in which, respectively, the transboundary externality is and is not taken into account in the determination of the optimal policy by individual local policymakers. We show that it is not obvious that transboundary externalities are a source of inefficiency per se since this is strictly related to the spatial features of the initial distribution of pollution. If the initial pollution distribution is spatially homogeneous then the local and global solutions will coincide and thus no efficiency loss will arise from transboundary externalities, but if it is spatially heterogeneous the local solution will be suboptimal and thus a global approach to environmental problems will be needed to achieve efficiency. From a normative perspective, in this latter (and most realistic) case we also quantify the amount of policy intervention needed at local level in order to achieve the globally desirable goal of pollution eradication in the long run. Our conclusions hold true in a number of different settings, including situations in which the spatial domain is either bounded or unbounded, and situations in which macroeconomic–environmental feedback effects are taken into account.     

An explorative study of corporate travellers’ perception at a German airport

The modern working environment is changing at a fast pace due to factors such as globalisation, digitalisation, and demographic trends. Taking an exploratory approach, this study examines how prevailing factors shaping the working world may influence the perception of business air travellers. Relevant factors are identified through a literature review, which results are confirmed by expert interviews (N = 11). Business travellers are surveyed (N = 67) at Munich Airport regarding their personal experiences and their evaluations of these identified factors. Their perceptions concerning the psychological and physical experience, digitalisation, age, and gender are examined in detail.Findings provide insights into the development of business air travel, with a focus on German business travellers. Despite the influence of advanced information and communications technology, survey results reveal that air travel might stay an essential part of the working world, as face-to-face meetings are not fully replaceable. Increasing multi-partner project work and flexible work structures could even lead into an increase of air travel. The study also delineates recommendations and research potential, such as the extension of the study in the light of the global COVID-19 pandemic. The question of how trends within the working world influence the perception of business related air travel is rarely studied. This study contributes to this gap in the scientific community.     

Does economic growth and energy consumption drive environmental degradation in China’s 31 provinces? New evidence from a spatial econometric perspective

The panel data analysis points to economic and social factors contributing to NO_x, PM_2.5, PM₁₀, SO₂, and VOCs in China’s 31 provinces. The spatial correlation analysis using Global and Local Moran’s I values indicates the existence of a significant and positive spatial autocorrelation with respect to environment, economy and energy, and the high spatial correlation is evident in the eastern region, covering the northern part of Yangtze River Delta, Huaihai Economic Zone, and the lower reaches of the Yellow River Economic Belt. The empirical estimation is performed through spatial lag and spatial Durbin models. All emitted air pollutants in 31 provinces have significant spatial dependence and strong spillover effects. There is an inverted U-shaped relationship between emitted air pollutants (NO_x, PM₁₀, VOCs, and PM_2.5) and per capita GDP, which follows the EKC hypothesis. The relationship between SO₂ and per capita GDP does not follow the EKC hypothesis. There is a positive relationship between pollutant emissions and coal consumption, which is consistent with current studies for various countries like Canada, Denmark, UK and US and regions like New York State. However, the effects of science and technology investment on air pollutants are mostly positive, which is not as policy expected.     

新疆棉农残膜回收行为影响因素及实证研究*——基于棉农的调研数据

［目的］为响应农业农村部“农业绿色发展五大行动”，加强农业面源污染防治，缓解新疆棉田残膜危害，基于新疆棉农的问卷调查研究棉农的残膜回收行为。［方法］采用描述性统计和Logistic回归模型分析影响新疆棉农残膜回收行为的因素。［结果］（1）新疆农用地膜回收率低，地膜污染形势严峻。（2）棉农对残膜危害认知缺乏，对残膜回收的间接价值认识不足，影响新疆残膜回收效率。（3）残膜回收的成本收益是影响棉农残膜回收行为的关键因素，其他如棉农年龄、种棉年限、对残膜危害的认知等自身特征，以及农户劳动力数量、政府对残膜污染的关注程度等因素对棉农的残膜回收行为有重要影响。［结论］网络及电视广播等现代媒体对棉农的残膜危害认知水平有较大影响，棉农更愿意采用成本更节约的焚烧、堆地的残膜处理方式。因此提出引导棉农残膜回收、提高棉田残膜回收效率的对策建议。     

Can stable environmental protection officials’ tenure reduce illegal emissions?

Based on the day-night PM_2.5 difference of the nearest atmospheric monitoring points to measure whether there is illegal emission, this paper explores the impact of environmental protection officials' tenure (EPLT) on illegal emissions. The results show that there is a positive correlation between EPLT and illegal emissions. Stable EPLT can reduce illegal emissions by increasing environmental information disclosure and environmental subsidies. It can increase illegal emissions by weakening public pollution reporting and media supervision, environmental law enforcement and promoting corruption. In addition, EPLT can increase illegal emissions as EPLT is less than 3.55 years, while EPLT can increase illegal emissions as EPLT exceeds 6.21 years. Further, when mayor's tenure and EPLT are both stable, the promotion effect of EPLT on illegal emission is stronger. Stable company director's tenure can also aggravate the promotion effect of EPLT on illegal emissions.     

多传感器长途客车智能新风系统设计研究

本研究设计了一种结合二氧化碳传感器、PM2.5粉尘传感器、TVOC传感器来实现智能更新长途客车封闭空间内污浊空气的长途客车车载新风系统。本系统由各项传感器实时采集车厢内CO2、PM2.5、TVOC等数据上传至单片机,单片机判断各项数据是否超过设定阈值,若超过设定阈值,新风系统自动工作改变进、排风量;反之,新风系统不工作,实现智能控制。实验证明,本系统具有明显地改善长途客车内空气质量的效果,能够更好地保护人体健康。     

"利剑斩污"行动下石家庄市挥发性有机物的污染特性变化研究

为研究石家庄市在"利剑斩污"行动管控期和非管控期挥发性有机物(VOCs)的污染特性变化,在2个时间段内对石家庄市3个国控点进行采样分析。通过苏玛罐(SUMMA罐)进行样品采集,利用气相色谱/质谱联用(GC/MS)仪对石家庄市区3个国控点的VOCs进行定性定量检测分析。结果表明,监测期间主要的特征污染物是二氯甲烷、二氯丙烷、苯和甲苯。与非管控期间相比,管控期间各污染物的质量浓度均有所降低,总VOCs平均质量浓度降低45.107μg/m~3,二氯甲烷质量浓度降低8.796μg/m~3,二氯丙烷质量浓度降低3.750μg/m~3,苯质量浓度降低18.285μg/m~3,甲苯质量浓度降低16.895μg/m~3。大气环境调控策略的实施,有效降低了VOCs浓度,减少了空气污染程度,空气质量改善效果显著。"利剑斩污"行动期间采取的相关举措,对于制定常态化下VOCs的防治对策具有一定的参考价值。     

农户生态耕种行为及其影响因素研究——以江西省为例

[目的]为清晰识别影响农户生态耕种行为的主要因素,以期为加强耕地生态保护、保障农作物质量安全、提升农户耕种收益、实现农业现代化目标提供参考。[方法]基于江西省11市47县(区)1488份农户微观调查数据,在分析农户生态耕种特征基础上,运用二元Logistic和Probit模型对农户生态耕种行为影响因素开展实证研究。[结果]农户生态耕种10种具体行为的采纳情况差异明显,其中施用有机肥采纳程度最高,生态农业模式采纳程度最低。农户采纳生态耕种整体水平不高,但仍具备进一步推广的潜力。家庭劳动力比重、生态耕种成本认知、新型农业经营主体、法律法规认知、生态耕种收益认知、生计分化和生态环境认知等解释变量是影响农户生态耕种行为的主要内部因素,政府补贴、农田基础设施、生产交流程度、耕地质量变化和生态耕种信息获取难度等则是主要的外部影响因素。[结论]政府及基层管理部门应在推动农户非农就业生计、大力培育新型农业经营主体、加强生态耕种宣传与推广、完善政策扶持与管控机制等方面制定针对性的政策措施。     

新型室内空气污染物——SVOC危害与研究进展

当今社会,室内空气质量受到越来越多的关注。研究表明,室内空气污染中除了大家熟知的甲醛、挥发性有机化合物,还有一种半挥发性有机化合物(SVOC)。目前,我国室内SVOC污染研究还处于起步阶段,相关研究还比较少。本文主要对现阶段室内SVOC污染状况及其健康风险评价内容进行梳理、分析与总结,推动室内SVOC相关研究发展,以完善我国室内空气污染物检测体系,提升室内环境安全水平。