农产品中重金属风险评估的研究与进展

对环境污染物重金属导致农产品安全方面的风险评估研究进展进行了调查。参考了世界卫生组织/世界粮农组织的食品添加剂联合专家委员会(JECFA)、欧盟、英国、美国等农产品中重金属风险评估案例。农产品中重金属风险评估有自身的特点,危害鉴定的数据较少,膳食摄入量估计主要是总膳食研究。此外,近年来MonteCarlo模拟等数理统计分析手段在重金属风险分析中的应用为科学合理的决策提供了更多依据。     

基于Bayes方法的东海小黄鱼资源评析

利用东海区渔业资源动态监测资料、采用基于Bayes方法的PellaTomlinson模型对东海区小黄鱼(Pseudosciaena polyactis)渔业资源动态进行了科学评析,同时,在不同渔业政策选择下,对2004-2020年的资源量与渔获量进行了预测模拟研究。研究结果显示：东海区小黄鱼渔业资源的环境容纳量K为394 514t;内禀增长率r为1.146;1991年的资源生物量为338 493 t、尔后持续上升到1994年的370 923t。1994年以后又持续下降,到2003年下降到最低值111 253t;最大持续产量（Maximum sustainable yield,MSY）为107 806t 左右;支持MSY所需的渔业资源生物量为197 503t;支持MSY所需的捕捞努力量为441 097 6网次;当前资源量与环境容纳量K的比值为0.282,即当前资源量已不足原始资源量的30%;若2004年以后使用0.4的捕捞死亡系数,该渔业资源可以实现持续最优利用。     

原油管道外腐蚀风险评价

介绍了应用解析法评估腐蚀管道失效风险的方法,根据ASME B 31 G和DNV等规范建立了腐蚀管道失效概率计算模型,结合国外管道事故统计结果,应用伯努利能量方程建立了后果评价模型,论述了建立风险可接受标准的方法.     

管道计算机辅助断裂评定系统研究

管道断裂评定工作是管道系统安全运行的重要保证，应用计算机辅助手段进行油气管道断裂评定能够大大简化工程人员的工作，使断裂评定工作更趋科学化。重点分析了油气管道计算机辅助断裂评定系统的研究和开发，介绍了系统的设计原则、系统构成、总体设计、设计流程和系统的实现，并简要分析了系统评定过程及结果的可靠性，为管道断裂评定提供了科学依据。     

大冶市农田土壤中镉的空间分布特征及污染评价

矿山开采和冶炼是造成土壤重金属Cd污染的主要原因,了解典型区域土壤中Cd的空间分布特征及其污染现状,可为区域土壤污染防治与安全利用提供重要信息。本研究针对湖北省大冶市所有农田采集92个表层土壤样品和3个土壤剖面,利用GIS方法对土壤重金属Cd空间分布特征及污染状况进行了研究。结果表明大冶市土壤中Cd的含量范围为0.6 ~ 4.6 mg/kg,平均值为1.41 mg/kg,Cd迁移深度可达 40 cm。区域内土壤Cd污染范围较广,空间变异较大,还地桥镇、罗桥街办、陈贵镇等地农田土壤Cd含量较高。地积累指数评价结果显示大冶市大部分农田土壤为轻度、中度污染程度,在合理调整种植结构等方式下仍可保障农田安全利用。     

Agricultural zinc fluxes into soils and crops of central Iran at regional scale

Mass flux assessment can provide information that is essential for a sustainable management of elements in agricultural soils. In this article, we present an assessment of regional-scale averages of zinc (Zn) fluxes into agricultural soils and crops of central Iran for the period 1997–2011, using available databases such as regional agricultural statistics. The basic units of the balances were 15 townships of the provinces Qom, Isfahan and Fars. Averaged over the entire study region, the net Zn input into arable soil resulting from all fertilizer inputs – Zn removal with harvested crops was 1515 g ha^?1 yr^?1 across the entire region, with a range of 438–3009 g ha^?1 yr^?1 among townships. Estimated average Zn inputs with manure, mineral fertilizers, sewage sludge and compost were 1254, 531, 19 and 7 g ha^?1 yr^?1, respectively. The input-to-output ratio of these fluxes ranged from 1.8 to 12.9 among townships and averaged 6.1 for the entire study area. Considering that outputs other than with crop harvests are minor, Zn stocks are rapidly building up in the soils of the study region. Uncertainties in the manure and crop removal data were the main sources of estimation uncertainty in this study.     

Assessing the Potential Impact of Integrated Agricultural Research for Development (IAR4D) on Adoption of Improved Cereal-Legume Crop Varieties in the Sudan Savannah Zone of Nigeria

This article provides an assessment of the potential impact of operationalizing agricultural innovation platforms (IPs) in the Sudan Savannah zone of Nigeria on adoption of improved maize/legume crop varieties, as measured by the potential outcome approach. The results show that, if the whole population in the intervention area were exposed to these varieties, the adoption rate could be increased to 69% instead of 49%. The study also shows that exposure, as well as adoption, is influenced by numerous social and institutional factors and suggests that the operationalization of IPs could help boost the adoption rate to around 51%.     

LAND SENSITIVITY TO DESERTIFICATION IN THE DOMINICAN REPUBLIC: AN ADAPTATION OF THE ESA METHODOLOGY

Many elements determine land sensitivity to desertification, whose analysis requires multifactorial approaches to be used. The environmental sensitive areas methodology is a well‐known approach to estimate sensitivity to desertification that accounts for multiple interacting driving forces, conceived and validated in a Mediterranean environment. We show that the environmental sensitive areas methodology can be used, with minor modifications, in a tropical context, where it allows the discrimination among environments with different degree of susceptibility to degradation and resilience. The results obtained for the Dominican Republic show that 48·4% of its territory is critically sensitive to desertification, and 16·4% of it is highly critically sensitive to desertification, mostly because of intense and inadequate land use practices. Copyright © 2013 John Wiley & Sons, Ltd.     

Lessons from 10 years of stakeholder adoption of a soil bioassay for assessing the risk of spinach Fusarium wilt

Although the maritime Pacific Northwest (PNW) is the only region of the United States suitable climatically for spinach seed production, the acidic soils are highly conducive to spinach Fusarium wilt caused by Fusarium oxysporum f. sp. spinaciae. A soil bioassay developed to quantify the risk of spinach Fusarium wilt in fields has been offered to seed growers annually since 2010. Soil sampled from growers' fields each winter was planted with highly susceptible, moderately susceptible, and partially resistant spinach inbred lines, and the plants rated weekly to calculate a Fusarium wilt severity index (FWSI) and the area under the disease progress curve (AUDPC). Results for 147 soils tested from 2010 to 2013 have been published. This study examined results for an additional 248 soils tested from 2014 to 2019 with the bioassay modified to include an option of agricultural limestone amendment to the soils tested. FWSI and AUDPC were affected significantly (p < .001) by the main effects of soil and spinach inbred line, and the interaction of these factors. Correlation analyses showed a range in degree of association of FWSI and AUDPC with spinach seed crop rotation duration and soil properties, depending on the spinach inbred line (r = −.255 to –.267, n = 172 soils with characteristics suitable for correlation analyses). Stepwise regression models for 172 soils with relevant parameters for regression analyses identified spinach seed crop rotation interval, rate of agricultural limestone amendment, soil pH, and soil Fe, Mn, and Zn concentrations as most strongly associated with FWSI and AUDPC. However, the models accounted for ≤33.4% (R²) of the variability in Fusarium wilt risk. The soil bioassay remains a primary tool for spinach seed growers to select fields with low risk of Fusarium wilt.