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Vascular bundle connection between seed stalk and seed coat of Caragana arborescens

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Journal of Forestry Research 2018年第1期29卷 253-257页

作者： Zhihui Luan daowei zhou Diankun Shao School of Life Sciences Changchun Normal University 677 North Changji Road Changchun 130032 Jilin Province People's Republic of China Northeast Institute of Geography and Agroecology Chinese Academy of Sciences 4888 Shengbei Street Changchun 130102 Jilin Province People's Republic of China Jilin Provincial Institute of Forest Inventory and Planning 3698 Yatai Street Changchun 130022 Jilin Province People's Republic of China

The purpose of this study was to investigate the morphology, transmission route of photosynthetic products in the seed stalk of Caragana arborescens Lam. at various stages after flowering and evaluate the role of the seed stalk in seed maturation using scanning electron microscopy. We found that the mature seed stalk mainly consisted of vessels,sclerenchymatous cells and parenchymatous cells. Elongated cells formed a ring at the junction between the seed stalk and seed, and a large hollow was produced by two layers of sclerenchymatous cells in the interior seed, which functions to sustain seed growth. The opening in the center of the ring was closed during an early stage of seed development, and the opening enlarged as the seed matured.There were two routes for material transport, which started from the seed stalk： one from the seed coat to the embryo,and another directly entering the embryo. Vessels, which are abundant in the seed stalk, are the pathway for absorption of nutrients by the seeds. The vessels were densely packed in the seed stalk, and secondary thickening of the cell wall of the vessels was characterized by net thread thickening, while the secondary thickening of the cell wall of the vessels within the seed was characterized by screw thread thickening. The morphological characteristics of the vessels were adaptive to its functions.

关键词： Caragana arborescens Seed coat Seed stalk Vascular bundle connection

Effects of fencing on vegetation and soil restoration in a degraded alkaline grassland in northeast China

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Journal of Arid Land 2014年第4期6卷 478-487页

作者： Qiang LI daowei zhou YingHua JIN MinLing WANG YanTao SONG GuangDi LI Northeast Institute of Geography and Agroecology Chinese Academy of Sciences University of Chinese Academy of Sciences School of Geography Science Northeast Normal University Graham Centre for Agricultural Innovation New South Wales Department of Primary Industries and Charles Sturt University

In order to restore a degraded alkaline grassland, the local government implemented a large restoration project using fences in Changling county, Jilin province, China, in 2000. Grazing was excluded from the protected area, whereas the grazed area was continuously grazed at 8.5 dry sheep equivalent（DSE）/hm2. In the current research, soil and plant samples were taken from grazed and fenced areas to examine changes in vegetation and soil properties in 2005, 2006 and 2008. Results showed that vegetation characteristics and soil properties improved significantly in the fenced area compared with the grazed area. In the protected area the vegetation cover, height and above- and belowground biomass increased significantly. Soil pH, electrical conductivity and bulk density decreased significantly, but soil organic carbon and total nitrogen concentration increased greatly in the protected area. By comparing the vegetation and soil characteristics with pre-degraded grassland, we found that vegetation can recover 6 years after fencing, and soil pH can be restored 8 years after fencing. However, the restoration of soil organic carbon, total nitrogen and total phosphorus concentrations needed 16, 30 and 19 years, respectively. It is recommended that the stocking rate should be reduced to 1/3 of the current carrying capacity, or that a grazing regime of 1-year of grazing followed by a 2-year rest is adopted to sustain the current status of vegetation and soil resources. However, if N fertilizer is applied, the rest period could be shortened, depending on the rate of application.

关键词： vegetation and soil restoration fencing grazing alkaline soil semi arid region grassland degradation

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农田氮肥残留效应及其影响因素

土壤与作物 2024年第2期13卷 201-214页

作者：马若男李强周道玮吉林省草地畜牧重点实验室/中国科学院东北地理与农业生态研究所吉林长春130102 中国科学院大学北京100049

氮肥利用效率的科学评估对指导农业生产至关重要。传统氮肥评估方案仅能反映当季肥料的利用效率,而忽视了氮肥的残留效应。本文综述了肥料氮的转运、氮肥残留数量、分布、利用及其影响因素,基于当前研究进展提出未来研究方向及相关研究... 详细信息

氮肥利用效率的科学评估对指导农业生产至关重要。传统氮肥评估方案仅能反映当季肥料的利用效率,而忽视了氮肥的残留效应。本文综述了肥料氮的转运、氮肥残留数量、分布、利用及其影响因素,基于当前研究进展提出未来研究方向及相关研究对农业管理实践的启示。农田输入的肥料氮,除了可以被当季作物吸收利用外,残留在土壤中的氮也可以继续被后续作物吸收利用,即评估肥效时,应该考虑氮肥的后效,而残留氮肥的回收利用受自身迁移和转化、作物种类、地力条件、气候环境、耕作管理等多个因素耦合影响。生产实践中,对决定残留氮肥回收效率的外部因素进行优化调控,诸如在长期浅根系/氮吸收低效作物种植后,轮作深根系/氮高效吸收型作物,合理密植,在干旱区适时灌溉保墒。针对作物氮肥喜好合理定制肥料类型,结合水肥一体化技术实施分次施肥,施氮同时配施微生物氮转化联合抑制剂均可有效提高氮肥总体利用率。利用15N同位素示踪技术,整合残留肥效和土壤氮素矿化等动态监测数据,配合作物类型、预期管理、目标产量等多要素数据,建立一套氮肥残留肥效的预测评估及氮肥减施的决策支持模型,对于指导未来的氮肥精准减施和提升农业生产效益具有重要科学意义。

关键词：农田氮肥利用效率氮肥残留残留氮肥回收施肥管理

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Effect of Autumn Cutting Date on Regrowth, Turning Green, Yield and Quality of <i>Leymus chinensis</i>Grassland in Songnen Plain, Northeast China

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American Journal of Plant Sciences 2018年第2期9卷 185-195页

作者： Yantao Song &ensp Wuyunna daowei zhou College of Environment and Bioresources Dalian Minzu University Dalian China Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun China

A field study was carried out to quantify the effects of different cutting time on Leymus chinensis population and community characteristic in Songnen grassland of northeast China from August, 2006 to August, 2007. The treatment interval was ten days with the remaining stubble height of 5 cm from 15th August to 4th October in 2006. Results showed that the L. chinensis made up about 90% of the dry matter of aboveground biomass, and there were about ten species in the L. chinensis community in the 1 m × 1 m plot. The L. chinensis and Kalimeris integrifolia regrew rapidly after autumn cutting in 2016. In the second year, the coefficients of the community similarity were high between the different cutting time treatments. The density, height, aboveground biomass, stem/leaf ratio, and crude protein of L. chinensis were not significant at the turning green stage and harvesting stage, the companion species of L. chinensis community contained higher crude protein, but the crude protein of the plant community were not significant. Thus, considering the weather factor for haymaking, the harvest dates should be concentrated from the middle ten days of August to the first ten days in September.

关键词： Leymus chinensis Autumn Cutting Hay Yield Quality Songnen Grass-land

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草地放牧饲养要素分析

中国草地学报 2024年第1期46卷 1-10页

作者：周道玮刘钟龄赵成振欧阳滔滔李强黄迎新中国科学院东北地理与农业生态研究所/吉林省草地畜牧重点实验室吉林长春130024 内蒙古大学生命科学学院内蒙古呼和浩特010021

饲养牲畜是草地放牧的目标,放牧饲养牲畜是草地饲草资源利用的最有效途径。放牧饲养要素包括草地生产率、适宜载畜率、饲草质量、牲畜生长需要和采食量及放牧方式。本文对这些要素进行了归纳分析,目的在于推进发展草地放牧饲养理论并推... 详细信息

饲养牲畜是草地放牧的目标,放牧饲养牲畜是草地饲草资源利用的最有效途径。放牧饲养要素包括草地生产率、适宜载畜率、饲草质量、牲畜生长需要和采食量及放牧方式。本文对这些要素进行了归纳分析,目的在于推进发展草地放牧饲养理论并推导草地生产和保护性利用的关键技术。本文介绍了草地生产率研究方法、适宜载畜率确定标准、划区轮牧区块数计算方法及间歇休牧期和放牧期确定方法。草地放牧饲养理论:基于土壤和气候,改善草地生产和饲草质量,制定适宜载畜率,确定合理放牧方式,满足放牧牲畜最佳生长需要,并维持草地健康,实现“双赢”或“三赢”。草地保护性利用关键技术:放牧场或割草场施肥,调整适宜的载畜率,延迟放牧及间歇休牧,确切的划区轮牧体系,放牧场和割草场等量配置,二时段饲养模式。

关键词：草地生产率饲草质量载畜率放牧方式

Effects of vegetation height and density on soil temperature variations

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Chinese Science Bulletin 2013年第8期58卷 907-912页

作者： SONG YanTao zhou daowei ZHANG HongXiang LI GuangDi JIN YingHua LI Qiang Institute of Grassland Science Northeast Normal University Key Laboratory of Vegetation Ecology Ministry of Education Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Graham Centre for Agricultural Innovation (alliance between Industry&Investment NSW and Charles Sturt University) Wagga Wagga Agricultural Institute

Reduction in vegetation cover caused by human activities has a great impact on soil temperature. It is important to assess how soil temperature responds to reduction of vegetation height and density. In this paper we first report the trends of mean annual soil surface and air temperatures recorded at the meteorological stations near the Ecological Research Station for Grassland Farming (ERSGF) from 1961 to 2007, then we setup an experiment using reed (Phragmites australis) stalks with different heights and densities to simulate effects of different vegetation height and density on soil and air temperatures. The warming rates of the mean annual soil and air temperatures were 0.043 and 0.041C a 1 , respectively. Changes of soil temperature were characterized by both increased mean annual maximum and minimum soil temperatures. At the experimental site, mean daily temperature, mean daily maximum soil and air temperatures increased significantly. In contrast, mean daily minimum soil temperature increased significantly while mean daily minimum air temperature decreased significantly as the height and density of reed stalks reduced during the experimental period. Mean diurnal soil temperature ranges were smaller than mean diurnal air temperature ranges. These results highlight that the importance of vegetation cover on soil and air temperatures.

关键词：土壤温度植被高度密度空气温度气温记录植被覆盖实验场地温度范围

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新型耐迁移橡胶防老剂的研究进展

化工进展 2023年第7期42卷 3708-3719页

作者：欧阳素芳周道伟黄伟贾凤中国石油化工股份有限公司科技部北京100728 中石化南京化工研究院有限公司江苏南京210048

首先介绍了橡胶防老剂的相关理论研究,橡胶材料老化的本质为自由基反应,其防护机理主要是抑制自由基的形成,实验研究集中于差示扫描量热、核磁、紫外分光、红外光谱等分析橡胶材料以及防老剂的结构变化,而理论研究则集中于分子模拟,包... 详细信息

首先介绍了橡胶防老剂的相关理论研究,橡胶材料老化的本质为自由基反应,其防护机理主要是抑制自由基的形成,实验研究集中于差示扫描量热、核磁、紫外分光、红外光谱等分析橡胶材料以及防老剂的结构变化,而理论研究则集中于分子模拟,包括解离能、溶解度、均方位移等参数计算。其次,通过对国内外商业化橡胶防老剂的使用现状进行追踪,分析了新型橡胶防老剂的开发与应用情况,包括胺类防老剂的改性方法、防老剂的复配研究以及具备特殊功能的新型防老剂应用等,结合几类耐迁移橡胶防老剂的结构特点和应用结果,指出具备耐迁移和低毒性等特点的新型橡胶防老剂是未来发展方向。最后,总结了新型耐迁移橡胶防老剂应集中于发挥防老剂大分子化和多官能化的协同作用,可以更好地适应橡胶工业的持续发展。

关键词：橡胶防老剂老化机理耐迁移分子模拟

吉林省敦化地区晚全新世泥炭沼泽孢粉组合特征及古植被

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应用生态学报 2006年第2期17卷 197-200页

作者：赵红艳周道玮东北师范大学吉林省生态恢复与生态系统管理重点实验室东北师范大学国家环境保护湿地生态与植被恢复重点实验室长春130024

对大桥泥炭地的孢粉进行了分析和年龄测定，根据孢粉组合、地层特征和^14C年龄将剖面划分为4个孢粉带，分别为2195±70～2045±70yr B．P．松为主的松．云冷杉-榛-栎-苔草组合带、2045±70～1745±70yr B．P．苔草为主的松-桦-榛-胡桃-... 详细信息

对大桥泥炭地的孢粉进行了分析和年龄测定，根据孢粉组合、地层特征和^14C年龄将剖面划分为4个孢粉带，分别为2195±70～2045±70yr B．P．松为主的松．云冷杉-榛-栎-苔草组合带、2045±70～1745±70yr B．P．苔草为主的松-桦-榛-胡桃-苔草组合带、1745±70～705±70yr B．P．松-榛．鹅耳枥-苔草．毛茛组合带和705±70yr　B．P．～1950yr　A．D．松-云冷杉-桦-苔草组合带．周围植被由温带山地针叶林（类似现今海拔1100m以上）、温带针阔混交林下部（类似现今海拔400～600m）和温带针阔混交林中部（类似现今海拔600～800m）过渡到温带针阔混交林上部（类似现今海拔800～1100m）．相应地，泥炭沼泽经历了孕育期、蓬勃发展期、继续扩张期和消亡期．

关键词：泥炭沼泽孢粉组合古植被晚全新世长白山区

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植物表型可塑性研究进展

生态学报 2017年第24期37卷 8161-8169页

作者：王姝周道玮贵州大学林学院贵阳550025 中国科学院东北地理与农业生态研究所长春130102

表型可塑性已成为生态进化发育生物学的核心概念,很大程度上由于植物可塑性研究的主要贡献,但人们仍远未完全了解表型可塑性的原因和结果。从整体角度理出表型可塑性研究发展的基本脉络,介绍研究内容、途径和简史,聚焦于几个主要方面的... 详细信息

表型可塑性已成为生态进化发育生物学的核心概念,很大程度上由于植物可塑性研究的主要贡献,但人们仍远未完全了解表型可塑性的原因和结果。从整体角度理出表型可塑性研究发展的基本脉络,介绍研究内容、途径和简史,聚焦于几个主要方面的研究进展及发展方向。现代可塑性研究的兴盛始于关于可塑性的进化学重要性的一篇综述,从现象的描述、对其遗传基础和可塑性本身进化的讨论,发展到探索其背后的发育机制、植物生长与适应策略、生态学影响等。未来可塑性研究应在重新理解和评价表型可塑性及其适应性的基础上,更关注自然条件下环境因子和可塑响应的复杂性。表型可塑性的生态-进化学意义仍将是未来研究的重点。

关键词：环境的复杂性构件特征可塑性的进化适应性可塑成本与限制发育的可塑