Plant–soil interactions in metal contaminated soils

The legacy of industrialization has left many soils contaminated. However, soil organisms and plant communities can thrive in spite of metal contamination and, in some cases, metabolize and help in remediation. The responses of plants and soil organisms to contamination are mutually dependent and dynamic. Plant–soil feedbacks are central to the development of any terrestrial community; they are ongoing in both contaminated and healthy soils. However, the theory that governs plant–soil feedbacks in healthy soils needs to be studied in contaminated soils. In healthy soils, negative feedbacks (i.e. pathogens) play a central role in shaping plant community structure. However to our knowledge, the nature of feedback relationships has never been addressed in contaminated soils. Here we review literature that supports a plant–soil feedback approach to understanding the ecology of metal-contaminated soil. Further, we discuss the idea that within these soils, the role of positive as opposed to negative plant–soil feedbacks may be more important. Testing this idea in a rigorous way in any ecosystem is challenging, and metal contamination imposes an additional abiotic constraint. We discuss research goals and experimental approaches to study plant–soil interactions applicable to metal-contaminated soils; these insights can be extended to other contaminated environments and restoration efforts.     

试验条件对标准橡胶塑性初值和保持率的影响与分析

通过测试不同厚度的试样和改变相同厚度试样的老化时间及温度来验证和分析试样厚度对塑性初值（P0）、老化条件对塑性保持率（PRI）的影响。试验表明,在其它试验条件不变的情况下,试样厚度偏大塑性初值（P0）也相应偏大,老化时间越长和老化温度越高,老化后的P30和塑性保持率（PRI）就越小。     

高贵化回交育种技术在凉蔗2号遗传亲系中的应用探讨

凉蔗2号亲系广泛应用高贵化杂交育种方法,引入异质血缘多次回交,打破连锁遗传,重组有利基因,促进血缘多样化,实现超亲。进行凉蔗2号亲系遗传高贵化杂交技术研究,有利于为凉蔗2号用作广亲和力亲本,实施远缘杂交制种工作提供有益借鉴。     

郏县文庙片区更新中历史文化资源的保护与利用

对河南郏县文庙片区的环境背景进行了分析,立足于其核心历史价值,对片区进行了详细规划设计。将片区的核心历史文化特色通过设计,在建筑、景观等层面表达出来,在保护古建筑的同时,借其核心优势,驱动整个片区的经济,并将部分收益返回来用于保护历史遗迹。通过案例的解析来阐明历史文化资源的有效保护利用手段。     

小组参与式教学在水产动物营养与饲料学中的探索与实践

为提高学生在教学过程中的参与度,培养学生自主学习与相互协作的能力,提出了以小组为单位参与水产动物营养与饲料学课堂教学的详细方案,制定了相应的考核评价体系。教学实践证明,这一方法对于提高学生学习的主动性、积极性,培养学生独立思考、自主解决问题的能力及团队合作精神是确实有效的。分析了应用中存在的一些问题,并提出了进一步改进完善的措施。     

Response of the soil fungal community to multi-factor environmental changes in a temperate forest

Both environmental and climatic changes are known to influence soil microbial biomes in terrestrial ecosystems. However, there are limited data defining the interactive effects of multi-factor environmental disturbances, including N-deposition, precipitation, and air temperature, on soil fungal communities in temperate forests. A 3-year outdoor pot experiment was conducted to examine the temporal shifts of soil fungal communities in a temperate forest following N-addition, precipitation and air temperature changes. The shifts in the structure and composition of soil fungal communities were characterized by denaturing gradient gel electrophoresis and DNA sequencing. N-addition regimen induced significant alterations in the composition of soil fungal communities, and this effect was different at both higher and lower altitudes. The response of the soil fungal community to N-addition was much stronger in precipitation-reduced soils compared to soils experiencing enhanced precipitation. The combined treatment of N-addition and reduced precipitation caused more pronounced changes in the lower altitude versus those in the higher one. Certain fungal species in the subphylum Pezizomycotina and Saccharomycotina distinctively responded to N fertilization and soil water control at both altitudes. Redundancy discrimination analysis showed that changes in environmental factors and soil physicochemical properties explained 43.7% of the total variability in the soil fungal community at this forest ecosystem. Variations in the soil fungal community were significantly related to the altitude, soil temperature, total soil N content (TN) and pH value (P < 0.05). We present evidence for the interactive effects of N-addition, water manipulation and air temperature to reshape soil fungal communities in the temperate forest. Our data could provide new insights into predicting the response of soil micro-ecosystem to climatic changes.     

农业科研单位青年科技人员思想政治工作初探

思想政治工作是党的建设工作的重要法宝，充分体现了党组织的统领全局作用和凝聚作用。随着农业体制机制改革的日益深入，农业科研单位正经历着复杂而又深刻的改革，同时，青年科技人员的思想也在悄然变化。农业科技创新归根到底取决于青年科技人员，面对青年科技工作者新的思想动态、精神状态的变化，必须开展有效的思想政治工作，以帮助青年科技人员树立正确的思想信念，克服错误的思想倾向，为深入推进农业科研单位健康、协调发展提供强大的精神正能量。     

某宾馆利用太阳能集中热水供应系统设计

随着人们生活水平的提高,对生活热水需求的激增促进了太阳能热水器的迅速发展。目前太阳能热水器的应用,主要还是以分户独立系统为主,未来太阳能热水系统的发展趋势是以集中式为主。针对该宾馆热水供应的要求和特点,为宾馆设计了利用太阳能提供热水的集中系统,进行了太阳能集热系统规划、设计计算和设备选型,为将来集中式太阳能热水系统的应用和发展提供参考。     

基于广告、技术、奖励的二级供应链效益最大化研究

基于技术进步视角，构建服务业FDI影响产业安全的理论模型，并采用1996-2013年的时序数据和分位数回归方法进行检验。实证结果表明，服务业FDI对技术进步的总效应为正；分位数回归进一步揭示，服务业FDI对技术进步的直接效应为正、间接效应为负，并在技术进步的低中分位点上，服务业FDI的直接效应大于间接效应，而在技术进步的高分位点上，服务业FDI的直接效应小于间接效应。研究证实，在技术进步的初期，服务业FDI会对产业安全发展产生直接的正向推动作用，但随着时间的推移，服务业FDI会威胁其产业安全。     

磁化水在农作物上应用的研究进展

针对磁化水对农业生产的影响,简述了国内外关于磁化水应用的研究动态和发展趋势,介绍了磁化水在促进作物种子萌发、增强抗逆性以及提高产量和改善品质方面的研究进展。