Evaluation of C18 solid‐phase extraction cartridges for the isolation of select pesticides and metabolites

Abstract

Nine different C₁₈ solid‐phase extraction (SPE) cartridges were evaluated for their efficiency at extracting nine pesticides and two s‐triazine metabolites from spiked deionized water samples. The SPE cartridges were found to contain nitrogen (N) and/or phosphorus (P) contaminants and varied in their extraction efficiency for certain pesticides and metabolites. Four of the nine SPE cartridges gave acceptable (70 to 120%) pesticide and metabolite recovery percentages, while five cartridges had marginal (50 to 70%) to poor (< 50%) recoveries. Statistical analyses showed that the poor to marginal recoveries found for three compounds could not be explained by considering several indigenous chemical and physical traits of the cartridge. It is suggested that proper SPE cartridge selection for pesticide recovery should be evaluated using several different cartridges.     

Appendix

Abstract

An atrazine‐degrading bacterial isolate (M91–3) was able to utilize simazine and cyanazine as N sources for glucose‐dependent growth. The degradation of these three 5‐triazine herbicides was also investigated in binary and ternary mixtures. The organism used atrazine and simazine indiscriminately, whereas cyanazine degradation was slow and delayed until the depletion of the two other herbicides. There was no apparent effect of other commonly used herbicides on the rate of atrazine degradation by M91–3.     

A case study of REDD+ challenges in the post‐2012 climate regime: The scenarios approach

The REDD+ (Reducing Emissions from Deforestation and Forest Degradation) partnership works to promote the reduction of greenhouse gas (GHG) emissions by protecting forests in developing countries through positive incentives. It is regarded as an essential component of the post‐2012 climate regime to stabilize GHG emissions and engage developing countries in worldwide mitigation endeavours. This study focuses on the gap between agricultural revenue and REDD+ compensation through the construction of several scenarios that explore the impacts of possible carbon price ranges.Three scenarios that reflect different potential policies are examined: (1) current carbon trading; (2) carbon trading with all forestry activities; and (3) carbon trading with all countries participating gradually over the coming decades. Data for developing the scenarios were obtained through a case study in central Kalimantan, Indonesia, by interrogating the potential for revenue by expanding agricultural land. The results indicate that REDD+ payments could not effectively compensate land users for their opportunity cost of deforestation, making it difficult for the governments to ensure that REDD+ money “reaches the ground” in terms of balancing the agricultural revenue of land users.     

Evaluating Local Benefits from Conservation in Nepal’s Annapurna Conservation Area

Protected areas are integral to the global effort to conserve biodiversity, and, over the past two decades, protected area managers have begun to recognize that conservation objectives are next to impossible to achieve without considering the needs and concerns of local communities. Incentive-based programs (IBPs) have become a favored approach to protected area management, geared at fostering local stewardship by delivering benefits tied to conservation to local people. Effective IBPs require benefits to accrue to and be recognized by those experiencing the greatest consequences as a result of the protected area, and those likely to continue extractive activities if their livelihood needs are compromised. This research examines dispersal of IBP benefits, as perceived by local residents in Nepal's Annapurna Conservation Area. Results reported here are based on questionnaire interviews with 188 households conducted between September and December 2004. Results indicate that local residents primarily identify benefits from social development activities, provisions for resource extraction, and economic opportunities. Overall, benefits have been dispersed equally to households in villages on and off the main tourist route, and regardless of a household's participation in tourism. However, benefits are not effectively targeted to poorer residents, those highly dependent on natural resources, and those experiencing the most crop damage and livestock loss from protected wildlife. This article provides several suggestions for improving the delivery of conservation incentives.     

Dryland characteristics and its optimized eco‐productive paradigms for sustainable development in China

Dryland area occupies 37% of the national territory in China. Desertification and other disasters have limited dryland sustainable development. Here we overview the dryland characteristics and desertification status and introduce four regionally optimized eco‐productive paradigms for dryland sustainable development, i.e., the mountain‐oasis paradigm in arid desert; the small watershed‐based paradigm on the Loess Plateau; the integrated animal husbandry paradigm on the Inner Mongolia Steppe and the agro‐pastoral transitional region; and three circle paradigm on the Ordos Plateau. These paradigms are established on the basis of regional landscape patterns and their underlying material and energy flow rules, and different functional belts are determined and capitalized upon with the integrated consideration of regional biogeophysical processes, biogeochemical cycles and biogeosocial relations. These paradigms cannot cover all complex landscape types, but provide theoretical frameworks and practicable models for dryland sustainable development in China.     

Comparison of 85Kr and 3H Apparent Ground‐Water Ages for Source Water Vulnerability in the Collyer River Catchment,Maine1

Abstract: Apparent ground‐water ages as determined by the noble gas isotope ⁸⁵Kr and the water isotope ³H are compared. Refined gas extraction methodology at the wellhead permits efficient collection of Kr for ⁸⁵Kr isotope enrichment. ⁸⁵Kr isochrones elucidate areas of much younger ground‐water ages than ³H. Declining ³H activities in the catchment prevent its correlation with the youngest measured ⁸⁵Kr ages. Source water for most drinking water supplies in the Collyer River catchment is recharged within 40 years BP (2004). Mean‐age (τ) transport modeling suggests uncertainty of ground‐water ages is greatest in the central basin area.     

Efficient and Practical Approaches to Ground‐Water Right Transfers Under the Prior Appropriation Doctrine and the Snake River Example1

Abstract: Water right transfers are one of the basic means of implementing changes in water use in the highly appropriated water resource systems of the western United States. Many of these systems are governed by the Prior Appropriation Doctrine, which was not originally intended for application to ground‐water pumping and the conjunctive management of ground water and surface water, and thus creates an administrative challenge. That challenge results from the fact that ground‐water pumping can affect all interconnected surface‐water bodies and the effects may be immeasurably small relative to surface water discharge and greatly attenuated in time. Although we may have the ability to calculate the effects of ground‐water pumping and transfers of pumping location on surface‐water bodies, mitigating for all the impacts of each individual transfer is sufficiently inefficient that it impedes the transfer process, frustrates water users, and consequently inhibits economic development. A more holistic approach to ground‐water right transfers, such as a ground‐water accounting or banking scheme, may adequately control transfer third‐party effects while reducing mitigation requirements on individual transfers. Acceptance of an accounting scheme can accelerate the transfer process, and possibly reduce the administrative burden.     

高墩大跨连续刚构桥施工期安全评价

针对高墩大跨连续刚构桥施工期结构概率失效的特性,提出了基于失效概率的安全评价方法.以徐水沟特大桥为工程背景,通过风险评定识别出施工最不利阶段--最大双悬臂时的主要风险因素即:节段特性模量的不确定性、梁体自重的不确定性以及预应力损失的不确定性.采用大型通用有限元程序ANSYS及蒙特卡洛法,计算徐水沟特大桥在最大悬臂时的失效概率,并确定施工期的目标可靠度.依据高墩大跨连续刚构桥施工期结构概率失效的评价结果,提出相应的风险控制措施.     

六安流动地磁测量异常的映震能力探讨

将安徽省六安地区流动地磁测线 12个流动地磁测点的∑ |δfi|异常与安徽中西部地震活动性作对比分析 ,初步结果为 :12个流动地磁测点的∑ |δfi|值较大 (∑ |δfi|≥Fu) ,一年内安徽中西部地区的地震活动性增强 ;反之 ,则安徽中西部地区的地震活动性较弱。此方法在地震的中短期预报中有一定的实用意义。     

CN-测定中显色剂配制方法的选择与保存时间

对2种氰化物显色剂配制方法进行了对比,发现用无水乙醇配制的显色剂具有方便,经济,实用,无毒且显色剂保存期长等优势。