基于活体微生物揭示蚯蚓对污泥耐药基因转归的影响

为削减污泥蚯蚓堆肥产物中耐药基因(ARGs),以无蚯蚓组为对照,采用叠氮溴化丙锭对蚯蚓堆肥样品进行预处理,探究蚯蚓对污泥中活微生物种群及其ARGs的影响.结果显示,与对照组相比,蚯蚓堆肥产物中有机物矿化度与降解量分别显著提升82.5%与5.2%(P<0.05).并且接种蚯蚓使其产物中放线菌门的丰度显著增加了65.6%(P<0.05),而厚壁菌门和拟杆菌门的丰度分别显著降低了74.7%和34.6%(P<0.05).相较于对照组,蚯蚓堆肥致使sul1、sul2、ermF和tetM基因丰度分别显著减少了66.5%、82.8%、72.8%和77.6%(P<0.05),但ermB的丰度显著增加了5.7倍(P<0.05).蚯蚓堆肥产物中intI1基因丰度比对照组显著降低了67.2%(P<0.05),蚯蚓处理后ARGs总绝对丰度为4.19×10¹³copies/g,ARGs总去除率为82.6%,比对照组高45.4%.研究表明,蚯蚓可通过改变活细菌种群结构,减少ARGs潜在活体宿主的丰度,进而降低其传播扩散的潜在风险.     

两类污染型下中低空风切变对PM2.5浓度影响

基于2015~2020年京津冀地区生态环境监测数据和多源气象数据,分析了北京地区0~3km中低空垂直风切变在不同PM_2.5等级下的演变特征。结果表明,风速日变化特征随着PM_2.5浓度升高而逐渐减弱,PM_2.56级污染时近地面风速日变化基本消失,甚至反向变化;白天边界层风速增大时段对应10m/(s·km)以下的风切变,20:00后增大至12~14m/(s·km),该现象随着PM_2.5污染加重变得更为显著,白天时段近地层垂直风切变较小值(<6m/(s·km))维持,可能是污染严重的信号之一;基于旋转经验正交函数分解法(REOF),将污染日下中低空垂直风切变分为无扰动型和压缩型,压缩型低压强度略强于无扰动型,无扰动型的PM_2.5浓度均值、峰值较压缩型更高,逆温强于压缩型,另外,无扰动型PM_2.5浓度增长期和边界层高度(PBLH)反向变化,压缩型PM_2.5浓度增长期和PBLH同向变化。     

Estimation of spatiotemporal trends in bat abundance from mortality data collected at wind turbines

Renewable energy sources, such as wind energy, are essential tools for reducing the causes of climate change, but wind turbines can pose a collision risk for bats. To date, the population-level effects of wind-related mortality have been estimated for only 1 bat species. To estimate temporal trends in bat abundance, we considered wind turbines as opportunistic sampling tools for flying bats (analogous to fishing nets), where catch per unit effort (carcass abundance per monitored turbine) is a proxy for aerial abundance of bats, after accounting for seasonal variation in activity. We used a large, standardized data set of records of bat carcasses from 594 turbines in southern Ontario, Canada, and corrected these data to account for surveyor efficiency and scavenger removal. We used Bayesian hierarchical models to estimate temporal trends in aerial abundance of bats and to explore the effect of spatial factors, including landscape features associated with bat habitat (e.g., wetlands, croplands, and forested lands), on the number of mortalities for each species. The models showed a rapid decline in the abundance of 4 species in our study area; declines in capture of carcasses over 7 years ranged from 65% (big brown bat [Eptesicus fuscus]) to 91% (silver-haired bat [Lasionycteris noctivagans]). Estimated declines were independent of the effects of mitigation (increasing wind speed at which turbines begin to generate electricity from 3.5 to 5.5 m/s), which significantly reduced but did not eliminate bat mortality. Late-summer mortality of hoary (Lasiurus cinereus), eastern red (Lasiurus borealis), and silver-haired bats was predicted by woodlot cover, and mortality of big brown bats decreased with increasing elevation. These landscape predictors of bat mortality can inform the siting of future wind energy operations. Our most important result is the apparent decline in abundance of four common species of bat in the airspace, which requires further investigation.     

Optimal post-warranty maintenance contracts for wind turbines considering availability

ABSTRACT

Outsourcing maintenance is an economical way for wind farm owners to address sophisticated and expensive maintenance operations of wind turbines. This paper proposes three options for the post-warranty maintenance contract of wind turbines from the perspective of service providers. Option 1 involves corrective maintenance only. In option 2, the first preventive maintenance is performed at a certain time point and after that periodic maintenance is carried out. Option 3 initiates with a preventive replacement and performs periodic maintenance subsequently. An availability target is set over the contract period and failing to satisfy the target incurs a penalty from the service provider. The objective is to determine the optimal preventive maintenance programs of option 2 and option 3 that minimize the contract servicing cost. Numerical examples are provided to illustrate the proposed policies. The results show that option 2 and option 3 are more effective than option 1 and their effectiveness grows when warranty and contract coverages increase.     

Effects of development of wind energy and associated changes in land use on bird densities in upland areas

Wind energy development is the most recent of many pressures on upland bird communities and their habitats. Studies of birds in relation to wind energy development have focused on effects of direct mortality, but the importance of indirect effects (e.g., displacement, habitat loss) on avian community diversity and stability is increasingly being recognized. We used a control-impact study in combination with a gradient design to assess the effects of wind farms on upland bird densities and on bird species grouped by habitat association (forest and open-habitat species). We conducted 506 point count surveys at 12 wind-farm and 12 control sites in Ireland during 2 breeding seasons (2012 and 2013). Total bird densities were lower at wind farms than at control sites, and the greatest differences occurred close to turbines. Densities of forest species were significantly lower within 100 m of turbines than at greater distances, and this difference was mediated by habitat modifications associated with wind-farm development. In particular, reductions in forest cover adjacent to turbines was linked to the observed decrease in densities of forest species. Open-habitat species’ densities were lower at wind farms but were not related to distance from turbines and were negatively related to size of the wind farm. This suggests that, for these species, wind-farm effects may occur at a landscape scale. Our findings indicate that the scale and intensity of the displacement effects of wind farms on upland birds depends on bird species’ habitat associations and that the observed effects are mediated by changes in land use associated with wind-farm construction. This highlights the importance of construction effects and siting of turbines, tracks, and other infrastructure in understanding the impacts of wind farms on biodiversity.     

樱桃萝卜对抗生素的富集及其潜在风险

为探究土壤抗生素污染的潜在生态和健康风险,于2021年6～9月进行温室土培樱桃萝卜试验,每隔6d向土壤中施用土霉素(OTC)或链霉素(STR)污水,并对其中生长的樱桃萝卜的生物量、萝卜组织抗生素含量和菌群耐药性进行分析.同时,通过风险商法、摄入量计算和小鼠饲喂试验对萝卜植株残留的抗生素和抗性细菌的潜在人体健康风险进行评估.结果表明,与未施用抗生素对照组相比,OTC的连续施用在第74d显著促进了萝卜植株生长,使其总生物量提高了23.1%,而STR的连续施用对萝卜植株的生长并无显著影响;萝卜植株对土壤中施入的两种抗生素均有一定的富集能力,STR在组织中的残留量高于的OTC1～2个数量级,抗生素在植物生长初期主要富集在叶中,生长后期在肉质根根颈部中的富集量显著增加(P<0.05);抗生素的施用使萝卜植株组织中可培养OTC和STR抗性细菌占总可培养细菌的比率分别增加了2.48×10^-6%～5.05×10^-4%和0.19%～3.32%;食用经抗生素暴露后的萝卜肉质根根颈部可增加机体对抗生素和抗生素抗性细菌的摄入量,但其健康风险较低(评估的风险商指...     

Local voices on renewable energy projects: the performative role of the regulatory process for major offshore infrastructure in England and Wales

There is currently a considerable emphasis on delivering major renewable energy infrastructure projects. Such projects will have impacts on local communities; some impacts may be perceived as positive but others will be viewed more negatively. Any just regulatory process for considering and permitting such infrastructure will need to heed the concerns that local communities voice. But what counts as a local voice? In this paper it is argued that the regulatory process plays a performative role, constructing what counts as a local voice. Furthermore, this has consequences for how regulatory deliberations proceed and the outcomes of regulatory processes. The empirical basis for this argument is a study of major offshore renewable energy infrastructure in England and Wales and the way that it is regulated through a specific regime – the Nationally Significant Infrastructure Projects (NSIPs) regime established by the Planning Act 2008. Through a detailed study of eight projects that have passed through the regime, the analysis unfolds the way that the voices of local residents, local businesses, local NGOs and local authorities are constructed in the key boundary object of the Examining Authority’s report; it then draws out the implications for the mitigation measures that are negotiated. The research suggests that what counts as a local voice is constrained by how the performative role of the NSIPs regulatory regime differentiates between interests and suggests that new ways of giving voice to local people are required.     

Assessing Risk to Birds from Industrial Wind Energy Development via Paired Resource Selection Models

When wildlife habitat overlaps with industrial development animals may be harmed. Because wildlife and people select resources to maximize biological fitness and economic return, respectively, we estimated risk, the probability of eagles encountering and being affected by turbines, by overlaying models of resource selection for each entity. This conceptual framework can be applied across multiple spatial scales to understand and mitigate impacts of industry on wildlife. We estimated risk to Golden Eagles (Aquila chrysaetos) from wind energy development in 3 topographically distinct regions of the central Appalachian Mountains of Pennsylvania (United States) based on models of resource selection of wind facilities (n = 43) and of northbound migrating eagles (n = 30). Risk to eagles from wind energy was greatest in the Ridge and Valley region; all 24 eagles that passed through that region used the highest risk landscapes at least once during low altitude flight. In contrast, only half of the birds that entered the Allegheny Plateau region used highest risk landscapes and none did in the Allegheny Mountains. Likewise, in the Allegheny Mountains, the majority of wind turbines (56%) were situated in poor eagle habitat; thus, risk to eagles is lower there than in the Ridge and Valley, where only 1% of turbines are in poor eagle habitat. Risk within individual facilities was extremely variable; on average, facilities had 11% (SD 23; range = 0–100%) of turbines in highest risk landscapes and 26% (SD 30; range = 0–85%) of turbines in the lowest risk landscapes. Our results provide a mechanism for relocating high‐risk turbines, and they show the feasibility of this novel and highly adaptable framework for managing risk of harm to wildlife from industrial development. Evaluación del Riesgo para las Aves por el Desarrollo de Energía Eólica Industrial Mediante Modelos de Selección de Recursos Pareados.     

适宜太湖蓝藻水华形成的风场辐散特征及其形成机制

对太湖周边17个气象观测站的7年常规观测资料聚类分析发现,在适宜蓝藻水华形成的高温、微风气象条件下,太湖湖面风场往往出现辐散特征,在此辐散风场的驱动下,蓝藻水华迁移过程必然与均匀风场驱动下有所不同;数值模拟结果显示,这种辐散风场是由于非绝热加热不均匀造成的局地次级环流叠加在弱的背景风场之上引起的;其强弱程度是受湖陆温差和背景风速共同决定的,并据此给出了湖面风场辐散强度指数.     

Challenge of global climate change: Prospects for a new energy paradigm

Perspectives on the challenge posed by potential future climate change are presented including a discussion of prospects for carbon capture followed either by sequestration or reuse including opportunities for alternatives to the use of oil in the transportation sector. The potential for wind energy as an alternative to fossil fuel energy as a source of electricity is outlined including the related opportunities for cost effective curtailment of future growth in emissions of CO₂.