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61.
62.
生态水文调节服务是生态系统服务的重要组成,能够有效调节地表径流,缓解暴雨洪涝灾害。但由于城市建设扩张、生态环境退化、极端降雨频发等因素,导致生态水文调节服务出现供需失衡。平原城市中地形水动力较弱及城市发展需求高的特征更是加剧了这种现象。基于生态系统供需视角,以生态水文调节率表征城市生态水文调节服务的生态供给,以暴雨洪涝风险表征城市生态水文调节服务的社会需求,构建应对暴雨洪涝灾害的平原城市生态水文调节服务供需研究框架。以典型平原城市天津市为例,应用SWAT模型、随机森林模型和ArcGIS定量测度城市生态水文调节服务供需水平,划分四种供需空间匹配类型,识别供需失衡关键区域,并进行五级规划干预等级分区。结果表明:(1)供给能力呈现“东南沿海高,西北近山低”的空间分布;需求水平表现出“多中心聚集,圈层向外递减”的分布规律。(2)供需空间分布呈现正相关关系,低供-低需在四种供需匹配类型中占据主导,同时空间聚集性最明显。(3)规划干预分区存在明显的空间差异,优先干预区占比5.41%,整体与建成区分布一致,大部分集中在市内六区,其次分布在滨海新区核心区,是未来规划治理的重点。研究结果为城市规划管理从... 相似文献
63.
IntroductionSeaweeds are a rich source of elements such as iodine, and are also able to accumulate contaminants such as trace elements.MethodsThe aim of this study was to assess the dietary exposure as well as the risk from iodine and trace elements in edible seaweeds for the French population using current consumption data. The contribution of seaweeds to overall dietary exposure to trace elements and iodine was evaluated, and for those substances with minimal contribution to overall dietary exposure, simulations were performed to propose increased maximal limits in seaweeds.ResultsCadmium, inorganic arsenic and mercury in seaweeds were very low contributors to total dietary exposure to these contaminants (0.7 % 1.1 % and 0.1 % on average, respectively). Dietary exposure to lead via seaweed may contribute up to 3.1 % of total dietary exposure. Dietary consumption of iodine via seaweed may contribute up to 33 % of total exposure to iodine, which makes seaweeds the strongest contributor to iodine in diet.DiscussionNew maximal values in seaweeds are proposed for the very low contributors to total dietary exposure: 1 mg/kg dw for cadmium, 10 mg/kg dw for inorganic arsenic and 0.3 mg/kg dw for mercury. 相似文献
64.
Peatlands as scientific archives of past biodiversity 总被引:5,自引:0,他引:5
Keith E. Barber 《Biodiversity and Conservation》1993,2(5):474-489
Peat bogs preserve past biodiversity in a way which is unique among ecosystems, but the full realization of this, and the exploitation of the various records which are archived in the stratified layers of peat, is only now beginning. Present knowledge of peat formation in ombrotrophic or rain-fed bogs is reviewed and the many advantages of such systems as proxy-data sources are summarized. Some results of recent work involving pollen analysis and human impact, pollution histories, volcanic ash layers, plant macrofossils and the prospects for a detailed proxy-climate record are presented. The present vegetation of such bogs is only a very partial view of their past biodiversity; the conservation of the peat that remains must have a high priority. 相似文献
65.
生态系统服务是自然生态系统及其物种提供的供给和维持人类生存的条件和过程,是人类通过生态系统的功能直接或间接得到的产品或服务,具有典型的区域性特征。黄土高原是黄河流域重要生态安全屏障,生态建设规模大、历时长,是我国生态系统服务研究的重要案例区。已有研究针对黄土高原生态系统服务进行物质量与价值量估算、权衡与协同关系识别和供需关系评估,但不同结论之间缺少归纳和对比。研究对近20年来黄土高原地区生态系统服务研究的文献总体特征和主要研究发现分析表明:相关中英文论文数量和被引频次整体呈上升趋势,研究内容上主要关注黄土高原生态系统服务的定量估算,近年来逐渐向生态系统服务权衡分析和供需关系评估拓展;黄土高原地区自退耕还林以来,各项生态系统服务总量呈上升趋势,呈现出东南增量较多、西北增量较少的空间格局;黄土高原地区供给服务和调节服务存在较明显的权衡关系,但在不同尺度上强度分异明显;区域内生态系统服务供给量和需求量均呈增加趋势,供需匹配状况具有明显时空差异。面向当前研究中物质量评估种类不足、价值量估算高度不确定、权衡与协同现象缺乏归因、空间流动性体现不足等问题,未来黄土高原生态系统服务研究有待加强面向生态... 相似文献
66.
《Revista espa?ola de geriatría y gerontología》2023,58(1):35-42
Last decade, the Government of Catalonia have urged an integrated care strategy for planning the care model to older populations living with frailty, multimorbidity and advanced illnesses. Based on international evidence that was reviewed by a group of experts from the Catalan Society of Gerontology and Geriatrics, we summarised some recommendation to adapt hospital-at-home care to older populations in our system. We defined Comprehensive Geriatric Assessment (CGA) hospital-at-home (HaH) as a specialised home hospitalisation service formed by interdisciplinary teams, characterised by using the clinical methodology of CGA, and by adapting geriatric units’ protocols for the provision of person-centred care at home. Main benefits of CGA-HaH in these populations are: response to heath crises according to individualised care plans based on the situational diagnosis carried out by Primary Care teams; provision of a comprehensive health and social approach tailored to the complexity of cases and situations; and adaptation of multipurpose hospitalisation, by working on different person-centred care, aspects, such as caregivers support on care provision, focusing on function or home adaptation. 相似文献
67.
Manfred Rösch 《Vegetation History and Archaeobotany》1993,2(4):213-232
The second part of a pollen profile from Hornstaad/Lake Constance (Germany), containing the Atlantic and Subboreal (6400 cal B.C. to 700 cal B.C.) is presented. The diagram has a sampling interval of 1 cm and an average time resolution of 10 years. The cereal curve provided the basis for cereal zones, which are used to classify the human impact. Twenty-six cereal zones can be distinguished, most of them divided into subzones, from 5500 cal B.C. to 700 cal B.C. They correspond to both known and, mostly, unknown settlements in the surrounding landscape from the Early Neolithic to the Late Bronze Age. Charcoal and chemical analyses as well as sediment accumulation, confirmed by accelerator dates, provide evidence for human impact on the environment.A contribution to the 8th IPC, Aix-en-Provence, Sept. 1992 相似文献
68.
仿脑组织体模是指可以有效模拟人脑组织形状、性质的等效材料组织或数字模型,可以在实验中代表人脑组织的某些生理特性从而达到特定的研究目标,根据其物理形态,通常可分为固体、液体、数字体模3类。仿脑组织体模具有安全经济,配置简单并且可重复使用的优势,被广泛应用于脑部疾病诊断、系统安全性评估等研究。本文就仿脑组织体模的分类、物理特性和脑科学研究应用3方面进行论述,在阐述当前仿脑组织体模与真实脑组织存在一定性质差异的同时也说明其在替代真实脑组织实验上有良好的应用前景。 相似文献
69.
摘要 目的:探讨基于老年综合评估结果指导(CGA)治疗对老年冠心病患者心功能、脂代谢和生活质量的影响。方法:本次研究将2020年6月-2022年1月在江苏省人民医院心血管内科接受治疗的106例老年冠心病患者,采用随机数字法将其随机分为对照组(常规药物治疗,53例)与研究组(对照组的基础上结合CGA治疗,53例)。对比两组疗效、心功能、脂代谢和生活质量相关情况。结果:研究组的临床总有效率为94.34%,明显高于对照组的79.25%(P<0.05)。研究组治疗3个月后左心室舒张期末内径(LVEDD)、左心室收缩期末内径(LVESD)低于对照组,左心室射血分数(LVEF)高于对照组(P<0.05)。研究组治疗3个月后高密度脂蛋白胆固醇(HDL-C)高于对照组,甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)低于对照组(P<0.05)。研究组治疗3个月后病情、体力、医疗状况、一般生活、社会心理状况、工作状况各维度评分高于对照组(P<0.05)。研究组的住院期间心脏不良事件总发生率低于对照组(P<0.05)。结论:基于CGA治疗老年冠心病,可有效改善心功能、脂代谢,降低住院期间不良事件发生率,提高患者的生活质量。 相似文献
70.
Field experiments were done at two widely separated sites in England (Tadcaster, North Yorkshire and North Wyke, Devon). In each case an old permanent sward was re-seeded after ploughing or by direct drilling, or was left intact and fertilised. The carbamate pesticide aldicarb was applied to half of each experimental plot. The effects of sward improvement and pesticide on various soil invertebrate groups were assessed. Soil-dwelling macrofauna arthropods were scarce at both sites. Stem-boring dipterous larvae, however, were numerous at both sites. At Tadcaster, Oscinella vastator was the only species present in the original sward, but 0. frit was by far the most prevalent species in re-seeded areas. These can only have arisen from direct oviposition of eggs by adults on or near the emerging seedlings and not by migration of larvae from buried turf or the desiccated old pasture.
Mites and Collembola were abundant. Their numbers were reduced initially by cultivation and pesticide usage, but the effects of these practices were transient and their numbers recovered to previous levels usually within 10 wk.
Earthworms were present at both sites. Deep burrowing species, e.g. Lumbricus terrestris and Allolobophora longa were less affected by the treatments imposed than species such as A. chlorotica and L. rubelius which usually live close to the soil surface. Effects on their numbers were in any case, short-lived.
No improvement method consistently provided the greatest herbage dry matter yield. Pesticide application, however, greatly increased seedling stand and/or herbage yield at both sites and showed the benefits of using crop protectants, especially on direct-drilled re-seeds. 相似文献
Mites and Collembola were abundant. Their numbers were reduced initially by cultivation and pesticide usage, but the effects of these practices were transient and their numbers recovered to previous levels usually within 10 wk.
Earthworms were present at both sites. Deep burrowing species, e.g. Lumbricus terrestris and Allolobophora longa were less affected by the treatments imposed than species such as A. chlorotica and L. rubelius which usually live close to the soil surface. Effects on their numbers were in any case, short-lived.
No improvement method consistently provided the greatest herbage dry matter yield. Pesticide application, however, greatly increased seedling stand and/or herbage yield at both sites and showed the benefits of using crop protectants, especially on direct-drilled re-seeds. 相似文献