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Species diversity in restoration plantings: Important factors for increasing the diversity of threatened tree species in the restoration of the Araucaria forest ecosystem
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作者 Taylor E. Shaw 《植物多样性:英文版》 CAS CSCD 2019年第2期84-93,共10页
The Araucaria forest ecosystem in southern Brazil is highly threatened: less than one percent of the original forest remains, and what is left is a fragmented agro-mosaic of mostly early-to-late secondary forest patch... The Araucaria forest ecosystem in southern Brazil is highly threatened: less than one percent of the original forest remains, and what is left is a fragmented agro-mosaic of mostly early-to-late secondary forest patches among high-yield agriculture and timber monocultures. Forest restoration initiatives in this region aim to restore degraded areas, however the limited number of species used in restoration projects represents a missed opportunity for species-rich plan tings. High diversity plantings represent a larger number of functional groups and provide a targeted conservation strategy for the high number of threatened species within this ecosystem. This study interviewed nurseries (Ns) and cultivated and planted, and what factors are driving the species selection process. An average of 20 species were reportedly used in restoration plantings, most of which are common, widespread species. Baseline data confirms that Ns and RPs have disproportionately low occurrences of threatened species in their inventories and plantings, supporting findings from previous research. Questionnaire responses reveal that opportunities for seed acquisition are an extremely important factor in order for nurseries to increase their diversity of cultivated species. Results also suggest that facilitating speciesrich plan tings for restoration practitioners would only be feasible if it did not increase the time required to complete planting projects, as it would minimize their ability to keep costs low. This study proposes solutions for increasing the number of species used in restoration practice-such as developing a comprehensive species list, fostering knowledge-sharing between actors, creating seed sharing programs, and in creasing coordination of planting projects. Long-term strategies inv olve complimenting traditional ex situ approaches with emerging inter-situ and quasi in situ conservation strategies which simultaneously provide long-term preservation of genetic diversity and increase seed production of target species. 展开更多
关键词 RESTORATION ARAUCARIA forest THREATENED species NURSERIES RESTORATION practitioners Decision-making
Design of Landscape Ecological Restoration for"Five Mining Areas"of the Laoqing Mountain in the Dianchi Lake Basin 预览
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作者 ZHU Guofei HU Yeqing +2 位作者 LONG Haijun CAI Fang SHE Lihua 《景观研究:英文版》 2019年第2期95-98,103共5页
Through analyzing basic conditions of the “five mining areas” in the Laoqing Mountain of the Dianchi Lake Basin, in Kunming City, South China, the ecological restoration design of “integrating engineering protectio... Through analyzing basic conditions of the “five mining areas” in the Laoqing Mountain of the Dianchi Lake Basin, in Kunming City, South China, the ecological restoration design of “integrating engineering protection and biological restoration, building the landscape ecological security pattern of the Laoqing Mountain” was proposed. Considering the different ecological functional areas, varying engineering measures, greening patterns, and irrigation means were selected for the ecological restoration, including site management, vegetation restoration, management and utilization etc.. These ecological restoration measures will produce favorable ecological benefits, and also take landscape effect and sustainable development into consideration, which will contribute to the ecological restoration of the “five mining areas”, and provide a scientific and feasible reference for the ecological restoration in China. 展开更多
关键词 "Five mining areas" of Laoqingshan MOUNTAIN LANDSCAPE ECOLOGICAL RESTORATION Site MANAGEMENT VEGETATION RESTORATION MANAGEMENT and utilization
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Power Restoration Prediction Following Extreme Events and Disasters
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作者 Romney B.Duffey 《国际灾害风险科学学报:英文版》 CSCD 2019年第1期134-148,共15页
This article examines electric power restoration following catastrophic damage in modern cities and regions due to extreme events and disasters. Recovery time and non-restoration probability are derived using new data... This article examines electric power restoration following catastrophic damage in modern cities and regions due to extreme events and disasters. Recovery time and non-restoration probability are derived using new data from a comprehensive range of recent massive hurricanes,extensive wildfires, severe snowstorms, and damaging cyclones. Despite their totally disparate origins, over three orders of magnitude severe wildfires and hurricanes have the same non-restoration probability trends, which are of simple exponential form. The results fall into categories that are dependent on and grouped by the degree of damage and social disruption. The implications are discussed for emergency response planning. These new results demonstrate that the scientific laws of probability and human learning, which dominate risk in modern technologies and societies are also applicable to a wide range of disasters and extreme events. 展开更多
关键词 Damage CATEGORIES Hurricanes RESTORATION PROBABILITY Storms WILDFIRES
图像中的政治:光复初期台湾媒介对国家认同的视觉建构 预览
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作者 凌富亚 《台湾研究集刊》 CSSCI 北大核心 2019年第3期82-89,共8页
日据时期,日本殖民者为根除台湾民众身上的中华文化烙印,实行“皇民化运动”,强制推行日语和灌输日本文化,致使部分台湾民众的民族意识与国家认同出现错乱。台湾光复之后,地方政府开始有意识地重塑台湾社会的中国认同。在这一过程中,媒... 日据时期,日本殖民者为根除台湾民众身上的中华文化烙印,实行“皇民化运动”,强制推行日语和灌输日本文化,致使部分台湾民众的民族意识与国家认同出现错乱。台湾光复之后,地方政府开始有意识地重塑台湾社会的中国认同。在这一过程中,媒介图像发挥了视觉叙事与意识形态宣传的重要作用,通过政治归属、文化归属、民族归属三个维度的图像展示,实现了国家认同的视觉建构。 展开更多
关键词 台湾 光复 图像 国家认同
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云南某铅锌污染场地修复研究 预览
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作者 孙晶 潘学军 《环境科学导刊》 2019年第2期56-60,共5页
土壤是生态环境的重要组成部分,也是人类赖以生存的主要自然资源[1]。随着我国产业结构调整及城市建设进程的加快,导致大量搬迁企业遗留的污染场地引发很多的环境问题。选用三种不同类型的钝化剂对云南某铅锌污染场地土壤进行修复研究,... 土壤是生态环境的重要组成部分,也是人类赖以生存的主要自然资源[1]。随着我国产业结构调整及城市建设进程的加快,导致大量搬迁企业遗留的污染场地引发很多的环境问题。选用三种不同类型的钝化剂对云南某铅锌污染场地土壤进行修复研究,结果表明:药剂A、B、C对土壤铅、锌、镉的钝化效果显著,但药剂B、C均会造成土壤中砷的活性释放。药剂A的钝化能力更全面,效果更好。为安全有效地治理重金属污染场地提供技术指导[2]。 展开更多
关键词 铅锌污染场地 重金属 原位钝化 修复研究 云南
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陶渊明的思想和艺术 预览
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作者 顾农 《南京师范大学文学院学报》 CSSCI 北大核心 2019年第1期1-10,共10页
陶渊明接受前人的思想遗产相当驳杂,而仍以儒家思想为主导。他的社会理想具有浓厚的复古色彩。其人生哲学以天命论为重要的基点。他既重视实际的物质生活,又强调加强道德修养,其践履形成了一种高尚的人格范型。他在艺术上充满了创新精神... 陶渊明接受前人的思想遗产相当驳杂,而仍以儒家思想为主导。他的社会理想具有浓厚的复古色彩。其人生哲学以天命论为重要的基点。他既重视实际的物质生活,又强调加强道德修养,其践履形成了一种高尚的人格范型。他在艺术上充满了创新精神,取得了极高的成就。 展开更多
关键词 陶渊明 自然 思想 复古 人生哲学 艺术创新
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重视斜视术后双眼视功能的重建
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作者 魏红 黄俊婷 刘陇黔 《中华眼视光学与视觉科学杂志》 CAS CSCD 2019年第4期241-244,共4页
双眼视是双眼输入的视觉信息进行加工整理最终形成三维立体视觉的过程,属于大脑皮层的高级认知活动。斜视因为眼位的偏斜产生复视和混淆视,进而引起视觉抑制、异常视网膜对应、注视异常、三级视功能受损等一系列双眼视异常,严重影响了... 双眼视是双眼输入的视觉信息进行加工整理最终形成三维立体视觉的过程,属于大脑皮层的高级认知活动。斜视因为眼位的偏斜产生复视和混淆视,进而引起视觉抑制、异常视网膜对应、注视异常、三级视功能受损等一系列双眼视异常,严重影响了双眼视觉形成和发育。手术治疗为斜视的主要的治疗方法,但斜视矫正术后大部分患者无法获得正常的双眼视功能,而斜视的治疗应以重建双眼视功能为目标。斜视治疗不仅要重视眼位的恢复,更要重视双眼视功能的重建。重建双眼视功能在减少斜视的复发率,提高斜视的治疗效果方面具有积极的作用,并大大提高斜视患者术后的生活质量。所以双眼视功能重建应在斜视治疗中占有更重要的地位。斜视的早期手术治疗是建立双眼视觉的先决条件,同时应重视术后正确的屈光矫正和弱视的治疗,正确选用训练手段,个性化制定训练方案,才能促进双眼视功能的重建。 展开更多
关键词 双眼视觉 斜视手术 重建
Restoration,Strengthening and Planning in Italian and German Reconstruction after World War Ⅱ:Essay in Three Steps 预览
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作者 Emanuela Sorbo 《土木工程与建筑:英文版》 2019年第2期115-124,共10页
Post WWⅡ reconstruction took place at a time of fundamental importance for our understanding of the divide,theoretical and technical,between consolidation,reconstruction and restoration.Indeed,this period represents ... Post WWⅡ reconstruction took place at a time of fundamental importance for our understanding of the divide,theoretical and technical,between consolidation,reconstruction and restoration.Indeed,this period represents the moment in which the earliest stages of this rift emerged.In this essay,we shall attempt to provide an account of this phenomenon by citing case studies considered important within the Italian and German context:post-WWⅡ reconstruction work in the Veneto region(at key sites such as the Basilica Palladiana in Vicenza,the Palazzo dei Trecento in Treviso and the Church of the Eremitani in Padua),reconstruction of the Alte Pinakothek in Munich,and reconstruction and work for new use of the hospital,Ospedale Maggiore,in Milan,as a seat for the Università Statale.Considering these instances provides us with an opportunity to reconsider the transition,theoretical and technical,between conservation of ruins and reconstruction of memory. 展开更多
关键词 CULTURAL heritage post-WWⅡreconstruction CULTURAL memory and IDENTITIES architectural RESTORATION and conservation
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农田土壤机械压实修复研究 预览
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作者 周艳丽 《中国农机化学报》 北大核心 2019年第1期141-144,共4页
农田土壤机械压实是由机械作业引起的土壤结构破坏,导致土壤质量下降,具有累积效果。通过农机技术对压实土壤进行修复,可以改善土壤三相比,提高土壤质量。深松耕地土壤容重降低15.62%,土壤孔隙度提高7.7个百分点,孔隙比提高36.51%;土壤... 农田土壤机械压实是由机械作业引起的土壤结构破坏,导致土壤质量下降,具有累积效果。通过农机技术对压实土壤进行修复,可以改善土壤三相比,提高土壤质量。深松耕地土壤容重降低15.62%,土壤孔隙度提高7.7个百分点,孔隙比提高36.51%;土壤含水量正常年份可提高0.99个百分点,干旱季节可提高1.22个百分点,而多雨季节则降低0.8个百分点;土壤速效氮、速效磷、速效钾分别提高21.4%、18.04%、12.6%。除应用农机技术外,还可以使用农艺技术对压实土壤进行修复,通过增加土壤有机质含量、作物合理轮作等降低土壤容重,提高土壤孔隙度,修复土壤压实。 展开更多
关键词 土壤 农业机械 土壤压实 修复
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反渗透膜耐氯及氯化修复研究进展 预览
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作者 柳圳 赵颂 +2 位作者 王志 韩向磊 王纪孝 《膜科学与技术》 CAS CSCD 北大核心 2019年第2期123-134,142共13页
活性氯的添加可以有效缓解反渗透膜生物污染的问题,但是也会破坏膜的分离层结构,造成膜选择透过性能的急剧变化.研制耐氯性能良好的芳香聚酰胺反渗透膜能简化预处理和清洗工艺,延长膜使用寿命,降低膜系统运行成本.此外,对氯化降解的反... 活性氯的添加可以有效缓解反渗透膜生物污染的问题,但是也会破坏膜的分离层结构,造成膜选择透过性能的急剧变化.研制耐氯性能良好的芳香聚酰胺反渗透膜能简化预处理和清洗工艺,延长膜使用寿命,降低膜系统运行成本.此外,对氯化降解的反渗透膜进行修复,能恢复膜的分离性能,延长膜使用寿命,同时也能减少废弃反渗透膜对环境的污染.综述了反渗透膜耐氯性能以及氯化修复两方面的研究进展.首先,简要介绍芳香聚酰胺反渗透膜的氯化降解机理及氯化引起的性能变化.其次,从物理保护、纳米材料改性、苯环修饰、酰胺键修饰以及联合多重机制等多方面介绍了目前耐氯反渗透膜的研制手段及方法.再者,简要介绍了几种膜性能修复试剂及其应用.最后,对耐氯膜制备和膜氯化修复的研究方向和发展前景进行了总结与展望. 展开更多
关键词 芳香聚酰胺 反渗透膜 耐氯性能 修复 研究进展
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科学保护“桂林之肾”:会仙岩溶湿地 预览
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作者 邹胜章 周长松 +5 位作者 朱丹尼 林永生 樊连杰 谢浩 王佳 李军 《中国矿业》 北大核心 2019年第A01期353-357,共5页
会仙岩溶湿地是亚热带低海拔地区最大的岩溶湿地,在中国乃至全球都具有重要的生态价值和研究意义。近几十年来,在自然和人为双重因素的影响下,会仙湿地——“桂林之肾”呈现出退化趋势,保护与恢复会仙湿地已经成为时代的必然。本文从形... 会仙岩溶湿地是亚热带低海拔地区最大的岩溶湿地,在中国乃至全球都具有重要的生态价值和研究意义。近几十年来,在自然和人为双重因素的影响下,会仙湿地——“桂林之肾”呈现出退化趋势,保护与恢复会仙湿地已经成为时代的必然。本文从形成原因、演化趋势、退化成因等角度对会仙湿地进行了系统介绍,并从地质、水文地质等角度对湿地修复的可行性进行了探讨,在此基础上给出了会仙岩溶湿地保护与恢复建议,研究结果可以为会仙岩溶湿地的修复与保护提供参考。 展开更多
关键词 会仙 岩溶 湿地 退化 修复
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Ecological Restoration Technology and Benefit Assessment of Karst Rocky Desertification Mountains in Xixiu District of Anshun City 预览
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作者 Li LAI Ying PENG +1 位作者 Yujie LIU Hongwei XING 《亚洲农业研究:英文版》 2019年第4期40-45,共6页
Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and l... Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and landscape pattern based on self-repairing capacity of the nature and combined with appropriate artificial measures. Since the natural restoration process of karst desertification mountain is very long,it needs to be supplemented by artificial vegetation restoration. This paper introduced the ecological restoration technologies implemented in karst rocky desertification mountains in Xixiu District,Anshun City of Guizhou Province,and also introduced the afforestation tending management measures. It assessed the ecological benefits of the ecological restoration project from five aspects: mountain community characteristics,vegetation coverage,species diversity,afforestation survival rate and landscape effect. 展开更多
关键词 KARST rocky DESERTIFICATION MOUNTAINS Ecological restoration Technical measures BENEFIT assessment Xixiu DISTRICT of Anhui CITY in Guizhou Province
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Tidal Asymmetry Changes in a Shallow Mud Estuary by a Restoration Project 预览
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作者 LIANG Huidi KUANG Cuiping +3 位作者 GU Jie MA Yue CHEN Kuo LIU Xu 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期339-348,共10页
The tidal asymmetry-induced siltation below tidal barriers is a worldwide problem that restricts regional socio-economic and environmental development.The hydrodynamic processes of the small mud estuary also feature a... The tidal asymmetry-induced siltation below tidal barriers is a worldwide problem that restricts regional socio-economic and environmental development.The hydrodynamic processes of the small mud estuary also feature a high uncertainty after estuary restoration measures.In this study,a hydrodynamic model based on the MIKE21 is used to quantify the responses of tidal asymmetry to a two-phase restoration project in Shuanglong Estuary,Bohai Bay,China.According to the numerical modeling results,the tidal flat removal in the upper estuary(first-phase restoration)induces the flood asymmetry switching to the ebb asymmetry in unrestored reach but enhances flood asymmetry in widening restored reach.Although the tidal asymmetry reverts to flood-dominated pattern after full restoration over the estuary,the imbalance between flood and ebb velocities is relieved.A possible net sediment transport pattern based on a comparison of dominant asymmetric current and actual sediment transport period shows net sediments in the upper estuary and inlet transport seaward and landward,respectively,in the first-phase restoration,whereas landward net sediment transport occurs in the whole estuary under the second-phase restoration scenario.Given these results,we assume that a switch from the flood-dominated estuary to ebb-dominated estuary can be caused by redesigning the cross-sectional profile.The quantitative comparison of Lagrangian residual currents also implies that a channel–shoal structure rather than a flat bathymetry can promote the mass transport.Therefore,reshaping the channel–tidal flat system in restoration projects can prevent the sedimentation of the estuary and improve the water environment. 展开更多
关键词 TIDAL asymmetry RESTORATION project MUD ESTUARY net SEDIMENT transport
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基于饮马河生态化修复堤型选择研究 预览
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作者 王桂娟 《吉林水利》 2019年第2期29-32,共4页
文章通过对饮马河打渔山段河道治理工程堤型方案优选,确定选用直斜式复合堤型,堤防防洪、防潮标准提高为50年一遇。这种直斜式复合堤型兼具工程防护与生态化修复功能于一体,既能满足海湾赶潮型河道在流域防洪、区域除涝和片区防潮等基... 文章通过对饮马河打渔山段河道治理工程堤型方案优选,确定选用直斜式复合堤型,堤防防洪、防潮标准提高为50年一遇。这种直斜式复合堤型兼具工程防护与生态化修复功能于一体,既能满足海湾赶潮型河道在流域防洪、区域除涝和片区防潮等基本要求又具有经济可行、绿色生态和便于施工等优点,对沿海地区同类工程具有较好的借鉴意义。 展开更多
关键词 生态化 修复 堤型 饮马河
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王昕退膜汤与益气固冲汤分期辨治崩漏
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作者 付露 王昕 《实用中医内科杂志》 2019年第1期4-6,共3页
王昕教授认为崩漏主要为气虚血瘀,气虚为本,血瘀为标;排卵障碍型异常子宫出血(AUB-O)临床表现与'崩漏'类似。治疗以'急则治其标,缓则治其本'为原则,灵活运用'塞流''澄源''复旧'治崩三法。先活... 王昕教授认为崩漏主要为气虚血瘀,气虚为本,血瘀为标;排卵障碍型异常子宫出血(AUB-O)临床表现与'崩漏'类似。治疗以'急则治其标,缓则治其本'为原则,灵活运用'塞流''澄源''复旧'治崩三法。先活血化瘀以治标,退膜汤(党参、黄芪、莪术、三棱、茜草、补骨脂、海螵蛸、赤石脂、三七粉);瘀血祛除后,益气固冲摄血以调其本,益气固冲汤(党参、续断、黄芪、白术、白芍、茜草、山茱萸,荆芥炭、棕榈炭、牡蛎、海螵蛸、龙骨、赤石脂)。伴心烦加香附、郁金疏肝解郁;伴胃脘不适加瓦楞子煅制酸止痛;伴夜寐欠佳加酸枣仁、首乌藤养心安神。阴道流血停止后,运用中医四期调周疗法,结合不同生理时期的阴阳转化、消长、气血变化规律,周期性用药,经后阴血亏虚,加熟地、白芍、当归滋阴养血,充盈胞宫、血海;排卵期重阴转阳,加丹参、五灵脂、红花等补肾活血,促进排卵;经前期是重阳维持期,加鹿角霜、补骨脂、杜仲等补肾阳,推动经血来潮;经期为重阳转阴期,宜活血化瘀,重在祛瘀,加赤芍、五灵脂、益母草等,使经血排出通畅。附崩漏-气虚血瘀(异常子宫出血)验案1则。 展开更多
关键词 排卵障碍 异常子宫出血(AUB-O) 气虚血瘀 塞流 澄源 复旧 退膜汤 益气固冲汤 四期调周 王昕 老中医经验 中医药治疗
Climate forcing of tree growth in dry Afromontane forest fragments of Northern Ethiopia: evidence from multi-species responses 预览
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作者 Zenebe Girmay Siyum J.O.Ayoade +1 位作者 M.A.Onilude Motuma Tolera Feyissa 《森林生态系统:英文版》 CSCD 2019年第2期132-148,共17页
Background: Climate-induced challenge remains a growing concern in the dry tropics, threatening carbon sink potential of tropical dry forests. Hence, understanding their responses to the changing climate is of high pr... Background: Climate-induced challenge remains a growing concern in the dry tropics, threatening carbon sink potential of tropical dry forests. Hence, understanding their responses to the changing climate is of high priority to facilitate sustainable management of the remnant dry forests. In this study, we examined the long-term climate-growth relations of main tree species in the remnant dry Afromontane forests in northern Ethiopia. The aim of this study was to assess the dendrochronological potential of selected dry Afromontane tree species and to study the influence of climatic variables (temperature and rainfall) on radial growth. It was hypothesized that there are potential tree species with discernible annual growth rings owing to the uni-modality of rainfall in the region. Ring width measurements were based on increment core samples and stem discs collected from a total of 106 trees belonging to three tree species (Juniperus procera, Olea europaea p. cuspidate and Podocarpus falcatus). Thesubsp. collected samples were prepared, crossdated, and analyzed using standard dendrochronological methods. The formation of annual growth rings of the study species was verified based on successful crossdatability and by correlating tree-ring widths with rainfall. Results: The results showed that all the sampled tree species form distinct growth boundaries though differences in the distinctiveness were observed among the species. Positive and significant correlations were found between the tree-ring widths and rainfall, implying that rainfall plays a vital role in determining tree growth in the region. The study confirmed the formation of annual growth rings through successful crossdating, thus highlighted the potential applicability of dendroclimatic studies in the region. Conclusions: Overall, the results proved the strong linkage between tree-ring chronologies and climate variability in the study region, which further strengthens the potential of dendrochronological studies developing in Ethiopia, and also has great i 展开更多
关键词 Climate-growth relationship CLIMATE change DRY AFROMONTANE forest RESTORATION TREE-RING width
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灌浆期涝害对小麦旗叶光合特性影响及降渍恢复效应 预览
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作者 王宏杰 李文阳 +3 位作者 邵庆勤 许峰 张从宇 闫素辉 《中国农业气象》 CSCD 北大核心 2019年第7期460-466,共7页
2015-2016年以小麦品种烟农19为材料,采用盆栽实验研究灌浆期持续6d和9d涝害处理对旗叶光合特性的影响及水分胁迫解除后旗叶光合特性的变化。结果表明:灌浆期涝害会显著降低小麦旗叶的净光合速率(P<0.05),但不同处理下降的幅度存在差... 2015-2016年以小麦品种烟农19为材料,采用盆栽实验研究灌浆期持续6d和9d涝害处理对旗叶光合特性的影响及水分胁迫解除后旗叶光合特性的变化。结果表明:灌浆期涝害会显著降低小麦旗叶的净光合速率(P<0.05),但不同处理下降的幅度存在差异;涝害6d处理(WL6)和涝害9d处理(WL9)净光合速率分别降至正常水分处理(对照,CK)的82.0%和71.5%;水分胁迫解除后3d,WL6处理的净光合速率得到恢复,与CK表现一致,而WL9处理的旗叶净光合速率与CK差异显著,仅恢复至CK的86.3%。涝害阶段及水分胁迫解除后3d,小麦旗叶SPAD值的变化趋势与净光合速率基本保持一致。与涝害9d处理相比,涝害6d处理进行降渍以后,小麦叶片的光合特性能得到较好恢复。涝害期间,WL6处理的旗叶胞间CO2浓度较对照显著升高,表明涝害6d后旗叶净光合速率下降的主要原因是由于非气孔因素所致;WL9处理气孔导度显著下降的同时,胞间CO2浓度却无显著变化,说明涝害9d后小麦叶片的低光合作用主要也是受到了非气孔因素的影响,与叶片气孔的张开程度无关。 展开更多
关键词 小麦 灌浆期 涝害 光合速率 恢复
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黑龙江省西部退化防护林修复方式初探 预览
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作者 王铁霞 《林业勘查设计》 2019年第1期22-23,共2页
简要介绍退化防护林所能采取的修复措施及其树种选择原则和使用条件,为志“之北”防护林建设提供借鉴。
关键词 黑龙江西部 退化防护林 修复 方式
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广水河河流水质调查及健康评价 预览
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作者 陈兰洲 陶可 +4 位作者 赵剑 吴新国 张渝蕊 魏思洁 陶越 《中南民族大学学报:自然科学版》 CAS 2019年第1期56-62,共7页
在充分调研分析国内外河流健康研究的基础上,建立了由15个评价指标构成的广水河河流健康评价指标体系,确定了河流健康状况的评价标准,将其健康水平划分为'很健康、健康、亚健康、不健康、病态'5个等级,运用AHP-综合指数法对广... 在充分调研分析国内外河流健康研究的基础上,建立了由15个评价指标构成的广水河河流健康评价指标体系,确定了河流健康状况的评价标准,将其健康水平划分为'很健康、健康、亚健康、不健康、病态'5个等级,运用AHP-综合指数法对广水河健康状况进行评价.结果表明:广水河健康综合指数为3.1963,健康状况总体处于亚健康水平.广水河的河流健康状况主要存在以下问题:水量和水资源承载力不足;部分河岸坍塌;水体污染,部分河段呈轻度富营养化状态;水土流失加剧而导致河床淤积;水生生物减少.根据评价结果及问题分析,提出了相应的保护及修复措施,为广水河流域的保护提供了可借鉴的决策依据,也对同类型的河流保护具有一定的指导意义. 展开更多
关键词 广水河 河流健康评价 AHP-综合指数法 修复措施
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泡菜直投菌对抗生素诱导的小鼠肠道菌群紊乱的改善效果研究 预览
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作者 陈书巧 郭佳汶 +5 位作者 程如越 袁文硕 彭天宇 陈功 张其圣 李鸣 《食品与发酵科技》 CAS 2019年第3期29-34,共6页
目的探究泡菜直投菌对抗生素诱导的小鼠肠道菌群紊乱的改善效果。方法选取36只Balb/c雄性小鼠,随机分为实验组、模型组与空白组(n=12)。实验组小鼠灌胃头孢曲松(40mg/d/只)+泡菜直投菌(109CFU/d/只);模型组小鼠灌胃头孢曲松(40mg/d/只)... 目的探究泡菜直投菌对抗生素诱导的小鼠肠道菌群紊乱的改善效果。方法选取36只Balb/c雄性小鼠,随机分为实验组、模型组与空白组(n=12)。实验组小鼠灌胃头孢曲松(40mg/d/只)+泡菜直投菌(109CFU/d/只);模型组小鼠灌胃头孢曲松(40mg/d/只);空白组使用等量生理盐水灌胃。连续灌胃7d后停止干预,继续喂养21d。喂养过程中每3d测量体重,每7d收集粪便,提取DNA,采用qPCR和二代测序法分析小鼠粪便细菌浓度及粪便菌落构成。28d实验结束后,处死小鼠收集相关样品,称量脏器质量,计算脏器系数。结果抗生素干预后3d开始,实验组和模型组小鼠体重显著低于空白组(P<0.05);停止干预后,实验组和模型组小鼠体重分别第15d和第21d与空白组无差异,第28d实验组小鼠肝脏系数高于模型组(P<0.01)。在抗生素诱导期间,实验组、模型组小鼠的粪便细菌总浓度下降,丰富度与多样性均与空白组有明显差异(P<0.01);粪便菌落构成中以厚壁菌门占明显优势,而空白组则以厚壁菌门和拟杆菌门两种菌群占优势。经21d自然恢复后,实验组与模型组小鼠粪便细菌浓度,菌落丰富度与多样性逐渐恢复至正常水平,实验组小鼠肠道菌群丰富度低于模型组和空白组(P<0.01),但其多样性指数更接近于空白组;粪便菌落组成中均以厚壁菌门占优势,拟杆菌门次之,且实验组的菌落构成优于模型组。结论抗生素的使用会造成小鼠肠道菌群紊乱,在抗生素投用期间联合使用泡菜直投菌有助于促进肠道菌群紊乱的恢复,并在一定程度上促进机体损伤的修复。 展开更多
关键词 泡菜直投菌 肠道菌群 改善效果 二代测序
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