Adaptive Water Resource Planning in the South Saskatchewan River Basin: Use of Scenarios of Hydroclimatic Variability and Extremes

The South Saskatchewan River Basin is one of Canada's most threatened watersheds, with water supplies in most subbasins over‐allocated. In 2013, stakeholders representing irrigation districts, the environment, and municipalities collaborated with researchers and consultants to explore opportunities to improve the resiliency of the management of the Oldman and South Saskatchewan River subbasins. Streamflow scenarios for 2025‐2054 were constructed by the novel approach of regressing historical river flows against indices of large‐scale ocean‐atmosphere climate oscillations to derive statistical streamflow models, which were then run using projected climate indices from global climate models. The impacts of some of the most extreme scenarios were simulated using the hydrologic mass‐balance model Operational Analysis and Simulation of Integrated Systems (OASIS). Based on stakeholder observations, the project participants proposed and evaluated potential risk management and adaption strategies, e.g., modifying existing infrastructure, building new infrastructure, changing operations to supplement environmental flows, reducing demand, and sharing supply. The OASIS model was applied interactively at live modeling sessions with stakeholders to explore practical adaptation strategies. Our results, which serve as recommendations for policy makers, showed that forecast‐based rationing together with new expanded storage could dramatically reduce water shortages.     

Characterization of human manure-derived biochar and energy-balance analysis of slow pyrolysis process

Biochars have received increasing attention in recent years because of their soil improvement potential, contaminant immobilization properties, and ability to function as carbon sinks. This study adopted a pyrolytic process to prepare a series of biochars from dried human manure at varying temperatures. The thermal analysis of human manure and physicochemical properties of the resulting biochars illustrated that human manure can be a favorable feedstock for biochar production. In particular, the porous texture and nutrient-rich properties of biochars produced from human manure and may significantly enhance soil fertility when used as used soil additives. A temperature range of 500–600 °C was optimal for human manure biochar production. Significantly, when the moisture content of the feedstock is lower than 57%, the system could not only harvest manure-derived biochar but also have a net energy output, which can be provide heat source for nearby users.     

Exposure to elevated ozone levels differentially affects the antioxidant capacity and the redox homeostasis of two subtropical Phaseolus vulgaris L. varieties

Ozone (O₃) has become one of the most toxic air pollutants to plants worldwide. However, investigations on O₃ impacts on crops health and productivity in South America countries are still scarce. The present study analyzed the differences on the enzymatic and non-enzymatic antioxidant system in foliar tissue of two subtropical Phaseolus vulgaris varieties exposed to high O₃ concentration. Both varieties were negatively impacted by the pollutant, but the responses between each variety were quite distinct. Results revealed that Irai has higher constitutive levels of reactive oxygen species (ROS) and ascorbate (AsA) concentration, but lower total thiol levels and catalase immunocontent. In this variety catalase protein concentration was increased after O₃ exposure, indicating a better cellular capacity to reduce hydrogen peroxide. On the opposite, Fepagro 26-exposed plants increased ROS generation and AsA concentration, but had the levels of total thiol content and catalase protein unchanged. Furthermore, O₃ treatment reduced the levels of chlorophylls a and b, and the relationship analysis between the chlorophyll ratio (a/b) and protein concentration were positively correlated indicating that photosynthetic apparatus is compromised, and thus probably is the biomass acquisition on Fepagro 26. Differently, O₃ treatment of Irai did not affect chlorophylls a and b content, and loss on the protein content was lower. Altogether, these data suggest that early accumulation of ROS on Fepagro 26 are associated with an insufficient leaf antioxidant capacity, which leads to cell structure disruption and impairs the photosynthesis. Irai seems to be more tolerant to O₃ toxic effects than Fepagro 26, and the observed differences on O₃ sensitivity between the two varieties are apparently based on constitutive differences involved in the maintenance of intracellular redox homeostasis.     

A novel dismantling process of waste printed circuit boards using water-soluble ionic liquid

Recycling processes for waste printed circuit boards (WPCBs) have been well established in terms of scientific research and field pilots. However, current dismantling procedures for WPCBs have restricted the recycling process, due to their low efficiency and negative impacts on environmental and human health. This work aimed to seek an environmental-friendly dismantling process through heating with water-soluble ionic liquid to separate electronic components and tin solder from two main types of WPCBs—cathode ray tubes and computer mainframes. The work systematically investigates the influence factors, heating mechanism, and optimal parameters for opening solder connections on WPCBs during the dismantling process, and addresses its environmental performance and economic assessment. The results obtained demonstrate that the optimal temperature, retention time, and turbulence resulting from impeller rotation during the dismantling process, were 250 °C, 12 min, and 45 rpm, respectively. Nearly 90% of the electronic components were separated from the WPCBs under the optimal experimental conditions. This novel process offers the possibility of large industrial-scale operations for separating electronic components and recovering tin solder, and for a more efficient and environmentally sound process for WPCBs recycling.     

Effect of additives in the Neem formulations on deposition,volatilization and persistence of Azadirachtin in spruce foliage

Abstract

Foliar deposits, volatilization and persistence of azadirachtin‐A (AZ‐A) were investigated after application of four spray mixes prepared from a wettable powder (WP) and three emulsifiable concentrate (EC) formulations of neem. They were applied at the dosage rate of 50 g AI in 4 L/ha onto potted spruce seedlings in a laboratory spray chamber. Droplet‐size spectra and deposits were assessed using Kromekote^® card/glass plate collection units. Foliar residues [dislodgeable residues (DR), penetrated residues (PR) and total residues (TR)] of AZ‐A and their volatilization were measured by HPLC at different intervals of time up to 60 h after treatment. Differences in the droplet‐size spectra and deposit levels were observed among the four spray mixes due to the influence of additives present in them. Dissipation half‐lives (DT₅₀) of the DR, PR and TR in the foliage were low (range, 19.5 to 38.9 h) and varied according to the residue type and the spray mix used. The DT₅₀ values of the DR were consistently lower (range, 19.5 to 31.9 h) than those of the PR (range, 30.5 to 38.9 h) due to preferential loss of the surface residues. The low DT₅₀ values observed for the DR and TR in the foliage sprayed with the WP spray mix were attributed to the particulate nature of the deposit. AZ‐A volatilized appreciably from the DR rather than from the PR. The variations found in the amounts of AZ‐A volatilized (42 to 58%) and unaccountable (38 to 46%) from the initial TR values in spruce foliage, after 60 h, were attributed to the physical form of the deposits on the target surface and the influences of additives present in the different spray mixes.     

石灰岩和砂岩地区豆科类植物紫花光叶苕(Vicia villosa)中铁和锰的不同分配模式

豆科类植物生物量的减少主要与氮和磷之间的平衡受到影响而有紧密的相关性。然而,其他营养元素之间的不平衡也能响应生物量的减少,比如铁和锰营养元素。选择了贵州茂兰相邻的石灰岩和砂岩地区土壤进行了野外种植实验。实验结果表明:生长着的豆科类植物铁(Fe)和锰(Mn)出现互为相反的分配模式:在砂岩地区生长的豆科类植物根部对铁的吸收相对高于石灰岩地区;而对锰的吸收,石灰岩地区高于砂岩地区。因此,植物根部的Fe∶Mn,砂岩地区高于石灰岩地区。这个结果说明豆科类植物根部对Fe和Mn的吸收存在不同模式。然而,在叶片中的Fe∶Mn砂岩地区和石灰岩地区之间基本没有区别,这说明铁和锰从根部到叶片的迁移具有不同模式。当叶片的Fe∶Mn(质量之比)低于2.9时,有可能响应豆科类植物生物量的减少。我们在研究植物与土壤的营养元素含量之间相关性时,越过环境因素,必须考虑植物内部随生长过程而发生变化的营养元素的化学计量,比如,生长着的植物中Fe∶Mn比值的变化等。     

水电站大型起重平衡梁的安全检测与复核

对某水电站桥式起重机并车抬吊使用的大型平衡梁系统进行了全面的安全检测与复核,获取了有效的数据与信息,并据此对平衡梁的安全状况进行了评估,为同类吊具的安全检测提供参考.     

增养殖区沉积界面营养物质平衡体系研究

通过1999年在大亚湾海水增养殖区现场的调查资料,分析了上覆水、表层沉积物、柱状样品中的TN、TP含量。结果表明:(1)沉积物中营养物质对水体的贡献或交换,主要来自于表层沉积物。(2)TN的溶出率比TP高,沉积界面N的平衡体系易受破坏,沉积物中N对水体作出的贡献比P大。(3)沉积物对水体中的P有吸附现象,经一系列的地球化学过程后,沉积物中的P释放较难。(4)增养殖区上覆水TP的含量较高,超标现象较多。基于以上研究结果,建议以沉积物中TN的含量作为赤潮监测的因子。     

石化污水氨氮源头控制措施的探讨

通过武汉石油化工厂在正常生产运行条件下的污水场进水氨氮分布平衡 ,弄清炼油废水氨氮的来源 ,找出了污水氨氮源头控制的重点是污水汽提装置的脱硫氨净化水和与设备有关的机泵冷却水等 ,并以此分析了氨氮源头控制的对策。