近52年西北干旱区极端温度事件季节性时空分析

利用西北干旱区83个气象站点1961—2012年逐日最低（高）气温资料,对其极端温度事件季节性时空变化规律进行分析与预测,以期更好地为其生态保护和农业生产服务。结果表明：(1)时间趋势上,日极端低（高）温均值呈上升趋势,尤其是1981年后升幅明显增加,冬秋季升温最显著;日极端低（高）温极低（高）值有增多趋势,其中暖昼（夜）日数有增加趋势,夜（昼）指数变化最快的季节为夏秋季;1979—1986年,上述指数变化趋势发生突变（冬季先开始）;除夏季日极端低温极低值外,其他指数在2013—2020年季节变化与1961—2012年的增减趋势一致。(2)空间分布上,暖昼（夜）日数最大值、冷昼（夜）日数最小值均在北疆分区,而内蒙-宁夏分区的增减速率变化最快;2013—2020年,新疆全境春季冷昼、冷夜日数急剧减少,内蒙-宁夏分区、南疆分区夏季日最低（高）气温极值急剧降低（上升）。     

1961—2012年山东省气温变化及对农业热量条件影响

为了解山东省近52 年的气温变化对农业热量条件和粮食生产的影响,据1961—2012 年气象站数据,利用GIS 方法提取气温变化和农业热量条件变化指标,分析山东省气温时空分布规律、变化特征 及对农业生产条件的影响。结果表明：（1）山东省及鲁西、鲁中、鲁东地区年、四季平均气温整体增温显著,2000 年后增温更明显。春、冬季和全年平均气温从1990s 以后增温显著,夏、秋季近52 年来气温有波动,但整体增温较小;（2）山东省东部增温幅度最大,西部最小,呈自西向东增加趋势;（3）山东省及3个地区秋、夏季气温倾向率较小,而冬季和春季呈“暖冬”、“暖春”现象;（4）山东省≥0℃和≥10℃积温呈上升趋势,特别是近10年上升幅度较大;全省≥0℃和≥10℃初终日间持续日数波动较大,呈上升趋势。     

江西省稻瘟病发生流行趋势和治理对策探讨

就江西省稻瘟病发生流行趋势、发病诱因及防治对策等进行了探讨,并对建立高效的稻瘟病防控体系以及解决病虫害防治中劳力短缺问题提出了建议。     

国内外粮食生产科技现状及发展趋势分析

“中国人的饭碗任何时候都要牢牢端在自己手上,我们的饭碗应该主要装中国粮。”粮食安全是国家安全的重要基础,保障粮食安全是一个永恒的课题,所以系统分析国内外粮食生产科技现状及发展趋势非常重要。从世界粮食生产科技特征及发展趋势、世界典型农业发达国家粮食生产科技的成功经验、新时期中国粮食生产科技发展趋势和重大科技任务等方面进行了研究,以期为粮食生产管理及研究领域相关科研人员等提供参考。     

Scale measurements as a conservation tool in endangered Zingel asper (Linnaeus, 1758)

• 1. Zingel asper (a percid) is a highly endangered endemic fish of the Rhone catchment (France). Scale reading was used to estimate age and growth rates in one of the two last remaining populations that are still present in relatively high densities (River Beaume).
• 2. Scale reading was validated for the first time in Z. asper by comparing back‐calculated lengths from scale annual increment to actual lengths obtained by individual mark–recapture monitoring. The impacts of age or sampling site on individual growth rates were explored using generalized linear models.
• 3. No major discrepancy was observed between actual and back‐calculated lengths. Longevity of Z. asper was inferred from the age data and did not exceed 3 years. Results showed variation in growth rates among ages (20 times higher for 1+ fish than for 2+ or 3+ fish) and also among sampling sites.
• 4. The present work provided the first estimates of annual growth rates in the Beaume population. This study also showed that scale reading allowed a valuable trade‐off between accuracy and conservation imperatives that often imply avoiding invasive techniques such as the implantation of passive integrative transponders.
• 5. Scale reading will be a valuable tool for future ecological studies in Z. asper and will help in developing conservation strategies for this species as longevity and growth patterns are two life‐history traits of major importance for the management of endangered populations.

Copyright © 2007 John Wiley & Sons, Ltd.     

河北省山区农业节水灌溉发展趋势与展望

为了缓解河北省山区农业用水压力,寻求适合河北省山区主要灌溉作物的节水灌溉方式,系统分析了河北省山区水资源的现状,通过实地调查、相关资料的搜集与整理,从灌溉面积、灌溉形式、灌溉用水量几方面分析了研究区1980~2003年农田灌溉的发展情况,得出其发展趋势。并以各分区主要灌溉作物为例,对不同节水灌溉方式下的节水灌溉面积、作物产量、灌溉水分生产效率的变化进行比较,分析得出使各分区主要灌溉作物达到节水、高产效果的灌溉方式。     

番茄褪绿病毒病预测预报模型的建立

研究烟粉虱传播番茄褪绿病毒Tomato chlorosis virus (ToCV)的发生规律,建立其预测预报模型,能够指导田间早期有效防治.本研究于2014年-2018年每年采集山东寿光蔬菜基地大棚番茄和杂草的植株叶片,并收集植株上携带的所有烟粉虱,以健康番茄、杂草叶片和室内饲养的健康烟粉虱为阴性对照;实验室ToCV...     

Improvement in feed efficiency and reduction in nutrient loading from rainbow trout farms: the role of selective breeding

Resource efficiency, the ratio of inputs to outputs, is essential for both the economic and environmental performance of any sector of food production. This study quantified the advancement in the feed conversion ratio (FCR) and reduction in nutrient loading from rainbow trout farming in Finland and the degree to which genetic improvements made by a national breeding program have contributed to this advancement. The study combined two datasets. One included annual records on farm-level performance of commercial rainbow trout farms from 1980 onwards, and the other included individuals across eight generations of the national breeding program. The data from the commercial farms showed that from 1980 onwards, the farm-level feed conversion ratio improved by 53.4%, and the specific nitrogen and phosphorus loading from the farms decreased by over 70%. Hence, to produce 1 kg of fish today, only half of the feed is needed compared to the 1980s. The first generation of the breeding program was established in 1992. The FCR was not directly selected for, and hence, the genetic improvement in the FCR is a correlated genetic change in response to the selection for growth and body composition. Since 1992, the estimated genetic improvement in the FCR has been 1.74% per generation, resulting in a cumulative genetic improvement of 11.6% in eight generations. Genetic improvement in the FCR is estimated to be 32.6% of the total improvement in the FCR observed at farms, implying that genetic improvement is a significant contributor to resource efficiency. The use of genetically improved rainbow trout, instead of the base population of fish, reduces feed costs by 18.3% and total production costs by 7.8% at commercial farms (by −0.266€ per kg of ungutted fish). For phosphorus and nitrogen, it can be assumed that the use of fish material with an improved FCR also leads to 18.3% less nitrogen and phosphorus flowing into an aquatic environment. Such improvements in resource efficiency are win–wins for both industry and the environment—the same amount of seafood can be produced with significantly reduced amounts of raw materials and reduced environmental impact.     

环介导等温扩增技术的最新研究进展

环介导等温核酸扩增技术是一种新型的核酸扩增技术,其核心原理是对靶基因片段的6个区域设计3对引物,实现对靶基因片段地快速、高效扩增。该技术目前已广泛的运用于一些领域。通过简述该技术的原理方法,在一些领域的运用,总结该技术国内外目前的研究进展以及改进措施,分析该技术未来的发展趋势,对环介导等温核酸扩增技术有一个全面的了解,以期为今后该技术的发展运用提供一定的参考依据。     

我国北方寒区塑料大棚闲置期开发利用现状及分析

针对我国北方寒区塑料大棚广泛存在的实际情况,分析了大棚闲置的原因及其危害,对我国北方寒区闲置大棚开发利用情况进行了概括总结,其中闲置大棚主要用于种植蔬菜、食用菌栽培、畜禽养殖、光伏结合温室等方面,并提出了闲置大棚开发利用存在的问题及发展趋势.同时,指出开展规模化开发利用闲置大棚关键技术研究是加速闲置大棚利用的有效手段;...