国家北方重要生态安全屏障保护与建设

把内蒙古建成我国北方重要生态安全屏障,是立足全国发展大局确立的战略定位。本文在阐述国家北方重要生态安全屏障概念和内涵的基础上,综述了近年来内蒙古在国家北方重要生态安全屏障保护和建设中取得的进展及效果,对生态服务功能基础进行全面分析总结,剖析了目前和未来生态安全屏障建设中面临的天然生态脆弱、部分生态系统退化、资源环境承载压力大等问题,最后从发展方向、关键技术、政策体系、工程布局和监管能力五个角度提出了内蒙古生态保护与建设的对策建议,为筑牢我国北方重要生态安全屏障提供思路。     

Economic Growth and Marine Biodiversity: Influence of Human Social Structure on Decline of Marine Trophic Levels

Abstract:  We assessed the effects of economic growth, urbanization, and human population size on marine biodiversity. We used the mean trophic level (MTL) of marine catch as an indicator of marine biodiversity and conducted cross-national time-series analyses (1960–2003) of 102 nations to investigate human social influences on fish catch and trends in MTL. We constructed path models to examine direct and indirect effects relating to marine catch and MTL. Nations' MTLs declined with increased economic growth, increased urbanization, and increased population size, in part because of associated increased catch. These findings contradict the environmental Kuznets curve hypothesis, which claims that economic modernization will reduce human impact on the environment. To make informed decisions on issues of marine resource management, policy makers, nonprofit entities, and professional societies must recognize the need to include social analyses in overall conservation-research strategies. The challenge is to utilize the socioeconomic and ecological research in the service of a comprehensive marine-conservation movement.     

基于安全保障的分布式电源选址定容优化研究

分布式电源的发展是我国智能电网发展中的重要方面之一,基于安全保障性,合理地对分布式电源进行选址定容,对于中低压配电网规划具有重要意义。分析了分布式电源对配网的具体安全性影响。提出以安全第一、成本最小、网损最小、电压偏移最小为目标的综合效用目标函数模型,并采用遗传算法求解。通过对IEEE9节点配电网络的算例分析验证了所提算法在分布式电源选址定容求解问题中的可行性和实用性。     

食品工业废渣以发酵技术生产菌体蛋白饲料的研究

为了将食品工业废渣中可被微生物利用的营养物质构成蛋白质的微生物菌体,采用以固态发酵法生产蛋白饲料。试验结果表明,通过组合菌株,在2t规模的发酵池里进行连续培养,较佳的控制工艺条件是：培养温度30℃,培养基初始水份65％,培养时间80h,产品的菌体蛋白达到了30％以上,粗纤维含量下降60％以下,废渣中灰分降低了30％以上,钙和磷分别提高了70％和205倍,并含有丰富的纤维素酶,提高了食品工业废渣的利用价值。     

餐厨垃圾水热炭化产物分配规律及液固产物特性研究

以实采餐厨垃圾为对象,探究了3种反应强度("温和"180℃-1h、"中等"220℃-2h和"剧烈"260℃-4h)下餐厨垃圾水热炭化三相产物分配规律及液固产物特性.结果表明,反应强度显著影响产物分配.随反应强度提升,固相产物(水热炭)产率先上升后下降;液相产物(炭化液)产率先降低后趋于稳定;而气相产物产率持续上升.但无...     

微生物群落对氨胁迫响应的宏基因组学研究

为探析厌氧消化微生物群落对氨胁迫的响应,在串联批次实验中引入氨氮(TAN)胁迫,结合宏基因组学分析,研究了不同TAN浓度下,厌氧消化系统的过程参数、群落结构/组成及其功能基因/代谢途径的响应.结果显示,TAN为3000mg/L时,系统性能逐步优化;TAN为6000mg/L时,甲烷产率逐步下降,并伴随着丙酸、丁酸积累.从...     

宠物食品加工废水处理工程实例

介绍了水解 接触氧化 气浮工艺在宠物食品加工废水中的应用。实践表明 ,在进水CODCr、BOD5和SS分别为 2 5 0 0mg/L、1 6 0 0mg/L和 2 5 0mg/L的情况下 ,出水的CODCr、BOD5和SS分别为 70mg/L、1 5mg/L和 4 0mg/L ,达到了《污水综合排放标准》(GB8978 96 )一级标准。经过 1年半的运行表明 ,该工艺具有运行稳定性好、处理效率高、操作管理方便的优点。     

我国新时期生态保护修复总体战略与重大任务

生态保护修复是美丽中国建设的重大任务,是加快推进生态文明建设的优先行动,是推动生态产品价值实现的重要基础。近年来,我国生态保护修复取得显著进展,但生态系统本底脆弱、保护修复基础薄弱、管理机制不协调等问题依然突出。在大力推进生态文明建设的新的历史时期,面对百年未有之大变局,我国生态保护修复工作所面临的形势更加严峻,与实现国家生态治理体系和治理能力现代化的要求依然存在较大差距,尚难以满足人民日益增长的优质生态产品需要。本文在总结近年来我国生态保护修复主要进展基础上,分析了未来一段时期生态保护修复面临的问题与挑战,提出新时期生态保护修复应以习近平生态文明思想为统领,以提升生态系统服务功能、协同改善生态环境质量、维护国家生态安全为核心,探索构建生态保护修复与污染防治统筹推进机制,强化监管制度设计、示范样板引领、体制机制创新,加快实现山水林田湖草整体保护、系统修复、综合治理,筑牢美丽中国生态根基。     

Factors affecting the quantitative uncertainty of the estimated short-term intake. Part II—Practical examples

ABSTRACT

The effects of the spread of residue concentrations in the samples derived from the selected supervised trials and the number of trials were studied on the magnitude and uncertainty of the short-term dietary intakes calculated with the proposed new procedure (IESTI_p) and that one used currently by the FAO (Food and Agriculture Organization) and WHO (World Health Organization) Joint meeting on Pesticide Residues (JMPR) (IESTI_c). The residue data of 10 pesticides were obtained from supervised trials conducted on apples and pears. The methods described in Part I were used for the calculations of the uncertainty. The results indicate that the ratio of IESTI_P to IESTI_c (φ_IESTI) is directly proportional to the ratio of the estimated maximum residue level (MRL), recommended by the JMPR; to the highest residue (HR) observed in supervised trials, and it may have a wide range depending on the particular conditions. The φ_IESTI becomes greater with the increase of the difference between the mrl or maximum residue limit (MRL, established by the Codex Alimentarius Commission, CAC) and HR, and becomes smaller if the difference between the large portion (LP) and unit mass (U) decreases. The φ_IESTI ranged between 2 and 5.1 in the 16 cases examined indicating that the IESTI_p calculation method leads to higher intake estimates. The ratio of CV_IESTIp and CV_IESTIc ranged typically between 0.62 and 1.71. It rapidly increased up to 12 trials. For a larger number of trials, the ratio remained practically constant (1.69–1.71). The processing factor (PF) equally affects the MRL and HR values, therefore, it will not practically influence the φ_IESTI. The uncertainty of the estimated median residues depends on the spread and number of values in the residue datasets, which affects the uncertainty of the conversion factor (CF) and subsequently the uncertainty of the estimated IESTI_p. Residue values obtained from minimum nine independent trials are required for the correct calculation of the 95% confidence intervals of the calculated median residues. The uncertainty of the analytical results directly affects the median, HR values and indirectly the calculated mrl and the MRL derived from it. Therefore, it should also be considered for the calculation of the combined uncertainty of the conversion factors. For the correct interpretation of the results of dietary exposure calculations, the upper 95% confidence limit of the short-term intake should also be considered. However, it is not the current practice of regulatory agencies or JMPR.     

Determination and health risk assessment of enrofloxacin,flumequine and sulfamethoxazole in imported Pangasius catfish products in Thailand

The goals of this study were to determine the levels of three antibiotics – enrofloxacin, flumequine and sulfamethoxazole – in Pangasius catfish products imported into Thailand and to assess the health risks from consumption. To extract these antibiotic residues, acetonitrile, methanol and a small amount of formic acid were used as solvents. Determination of the antibiotics after extraction steps was carried out by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) technique. The results showed that 14 and 3 samples of Pangasius catfish products were contaminated with enrofloxacin and sulfamethoxazole, respectively. No flumequine residue was found. While the concentration levels of these antibiotics in most contaminated samples were lower than the European Union (EU) standard, one sample was found to contain sulfamethoxazole at 245.91 µg kg^?1, which was higher than the EU standard (100 µg kg^?1), indicating the likelihood that some contaminated freshwater fish products are widely distributed in Thai markets. Notably, the concentration levels of enrofloxacin in samples of Pangasius catfish with skin were higher than in non-skin products, suggesting that products with skin might retain more antibiotic residues than non-skin products. Although the hazard quotient showed that consuming imported Pangasius catfish products, based on the current consumption rate, will not adversely affect consumer health, antibiotic residues in Pangasius catfish products imported into Thailand should be continually monitored.