武汉市都市发展区地表温度季节性空间分布与驱动力分析

基于2015年武汉市都市发展区30 m空间分辨率的Landsat 8遥感影像反演近地表温度(LST),运用地统计学、地理加权回归(GWR)等方法,分析都市发展区、生态绿楔以及主城区四季LST时空分布规律和各驱动因子的作用机制,以期为更全面、科学地规划城市发展空间布局和缓解热岛效应提供借鉴.结果 表明:(1)与单一的普通最小二乘回归(OLS)相比,线性逐步回归(LSR)可以寻找最优的多驱动因子组合模型,与LSR拟合的结果相比,GWR模型R2值提高了0.04～0.09,且AIC值均明显减小;(2) LST存在空间聚集关系,“高-高”聚集主要发生在主城区、新型城镇发展区、主要交通干线沿线等更容易造成高温聚集的人工表面,其中夏季“高-高”聚集网格数最多且占比最大,而“低-低”聚集四季均主要发生在各大湖泊水系;(3)绿楔生态用地降温幅度各异,春季降温幅度不明显,夏季降温幅度最显著,各绿楔生态用地降温均超过2℃,且在一定范围内,LST随着与绿楔距离增大而升高,达到一定距离时,会随着与绿楔距离增加而趋于平缓或呈下降趋势;(4)与前人研究相比,景观格局对LST变化的解释程度整体较低,其原因可能是快速城市化导致人工表面积增加,相应的人工绿地也将增加,使得城市景观格局更加零散,导致LST受多种相互作用因素的影响;(5)影响四季LST的驱动因子空间差异较大,夏季土地覆盖和景观格局与冬季土地覆盖、景观格局和人为活动的回归系数均为正值,说明高温或低温条件下这些驱动因子对全域升温作用明显.     

Systematic review of conservation interventions to promote voluntary behavior change

Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.     

Are older drivers’ driving patterns during an on-road driving task representative of their real-world driving patterns?

Abstract

Objective: The current study investigated whether older drivers’ driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

Methods: Two hundred and eight participants (male: 68.80%; mean age?=?81.52 years, SD?=?3.37 years, range?=?76.00–96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants’ real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant’s vehicle.

Results: During the 4-month period prior to completing the on-road driving task, participants’ median real-world driving trip distance was 2.66?km (interquartile range [IQR]?=?1.14–5.79?km) and their median on-road driving task trip distance was 4.41?km (IQR?=?2.83–6.35?km). Most participants’ on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n?=?198).

Conclusions: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants’ real-world driving patterns.     

Traditional agriculture in transition: examining the impacts of agricultural modernization on smallholder farming in Ghana under the new Green Revolution

Following the renewed effort at achieving a new green revolution for Africa, emphasis has been placed on modernizing smallholder agriculture through the deployment of improved inputs especially mechanized technologies. In Ghana, the government has in the last decade emphasized the provision of subsidized mechanized ploughing services to farmers alongside a rapidly growing private sector tractor service market. While mechanized technology adoption rates have increased rapidly, the deployment of these technologies has been without critical analysis of the impacts on production patterns and local agrarian systems. This paper examines the distributional impacts of agriculture mechanization on cropping patterns and farm sizes of smallholder farmers in northern Ghana using Geographic Information Systems (GIS) techniques, and semi-structured interviews with smallholder farmers (n=60). Specifically, comparative analysis of the field sizes and cropping patterns of participant farmers prior to and after the adoption of mechanized technologies was conducted. In-depth interviews were used to contextualize the experiences of smallholder farmers toward understanding how mechanization may be impacting traditional agriculture. Our findings reveal a mechanization paradox in which farm sizes are expanding, while cropping patterns are shifting away from traditional staple crops (pearl millet and sorghum bicolor) to market-oriented crops (maize, rice and groundnuts). This transition we argue, has adverse implications on the cultural dimension of food security, the organization of social life, and climate change adaptation. We recommend a retooling of the current agricultural policy focus to ensure context sensitivity for a more robust battle against food insecurity.     

The distribution and enrichment characteristics of copper in soil and <Emphasis Type="Italic">Phragmites australis</Emphasis> of Liao River estuary wetland

The aims of the present investigation were to reveal the distribution and enrichment characteristics of copper in soil and Phragmites australis of Liao River estuary wetland. The concentrations of copper in root, stem, leaf, and ear of Phragmites australis as well as in soil were determined to study the absorption capacity of copper by wild Phragmites australis of Liao River estuary wetland. The study was carried out at test pool of the Shenyang Agricultural University, and the experimental materials (soil, irrigating water and Phragmites australis) were derived from Liao River estuary wetland. The concentrations of copper in soil and Phragmites australis were 16.4441 to 49.0209 mg/kg and 0.8621 to 89.5524 mg/kg, respectively. The results indicated that the enrichment coefficients of copper in different tissues of Phragmites australis changed with the growth of Phragmites australis. The results revealed that the enrichment coefficients of copper in the whole Phragmites australis were greater than 1 at each growing stage of the Phragmites australis. The results also showed that the transfer coefficients of Phragmites australis to copper changed with the growth of Phragmites australis. The results revealed that the Phragmites australis had a good removal effect on copper from soil and had some characteristics of copper hyperaccumulator.     

Assessment using CFD of the wind direction on the air discharges caused by natural ventilation of a poultry house

Air inside poultry houses must be removed on a regular basis to prevent excess of heat, particles and noxious gases that can imperil animals. To cope with this issue, natural ventilation could be an effective method when assisted by accurate predictions. This study investigates air discharges caused by natural ventilation of a poultry house by means of a three-dimensional computational fluid dynamics (CFD) model. It solves the governing equations of momentum, heat and mass transport, radiative transfers and animal-generated heat. Wind directions of 0°, 36° and 56° (0° corresponds to a wind blowing perpendicular to the ridgeline) were investigated; the CFD model predictions achieved a RMSE of 1.2 °C and 0.6 g[H₂O] kg^?1 [dry air] for internal temperature and absolute humidity, respectively, when air blew with an angle of 36°. Air renewal rates (ARR) were 39.5 (±?1.9), 34.9 (±?2.2) and 33.6 (±?1.7) volumes of the building per hour, when air blew at 0°, 36° and 56°, respectively. Such ARR predictions served to know how the gases contained in air would likely spread downstream from the building in order to define regions of potentially high gas concentration that could endanger neighbouring habitable facilities.     

南京典型站点春季大气颗粒物数谱分布特征

利用TSI公司的APS和SMPS系统,于2017年4月在江苏省环境监测中心点位连续一个月进行大气颗粒物数谱观测,结果表明,南京市春季典型月份大气颗粒物数浓度和体积浓度均值分别为1.64×104cm~(-3)和1.65×106μm~3/m~3;核模态、爱根核膜态、积聚模态和粗粒子模态数浓度占比分别为22.72%,53.52%,23.72%和0.05%,体积浓度占比分别为0.01%,1.76%,55.82%和42.41%;颗粒物数浓度平均日变化呈现双峰结构;PM_(2.5)体积浓度和质量浓度具有高度相关性;存在明显的新生粒子事件,3~10 nm颗粒物数浓度小时均值短时7 500 cm~(-3)。     

网状季胺基阴离子吸附剂制备及吸附性能

以丝瓜络为原料,采用醚化-接枝技术制备出季胺基阴离子交换吸附剂。采用电镜扫描、傅里叶红外光谱、比表面积孔径分布测定仪和元素分析仪等仪器对其进行分析和结构表征,并考察了温度、p H和硝酸盐初始浓度等因素对NO-3去除率的影响。实验结果表明,在20℃,p H值为3~10时,NO-3的吸附率可达90%左右;在不同温度下该吸附过程用Langmuir等温线模型和Freundich等温线模型描述均可;与伪一级动力学方程相比,伪二级动力学方程能更好地描述其吸附动力学方程。     

密相塔半干法烟气脱硫塔内加湿降温及其对脱硫效率的影响

为了实现密相塔半干法脱硫工艺的精确加湿进一步提高系统脱硫效率,利用推导出的传热传质计算方法,得到烟气温度降低和加水量的关系.结合3组密相塔半干法工程实际数据,发现理论计算值和实测值误差区间仅为2.9％ ～5.4％.通过选取河北某钢厂210 m2烧结烟气密相塔半干法脱硫项目实际在线检测数据,发现循环脱硫灰含湿量为3％的系统脱硫效率整体高于含湿量为5％和4％的样品,最大值达93.56％.通过粒度分析、扫描电镜、X射线衍射及差热-热重对2种不同含湿量的循环脱硫灰进行表征,结果表明,含湿量为3％的循环脱硫灰较含湿量为5％的样品粒径小、比表面积大,无团聚现象,物相分析还证实相对于含湿量为5％样品,其Ca(OH)2和结晶水含量少,几乎都是CaSO4和CaS03干态物质,因此脱硫反应进行彻底,脱硫效率较高.