保龙高速公路生态系统的恢复与重建

分析了干热河谷地区的气候、地质、土壤、植被等特点;提出人工植被恢复的技术要求及保龙高速公路绿化生态恢复设计模式。     

川西干旱河谷区植被恢复机理及模式分析

干旱河谷区与石漠化荒地、沙化区等同属困难立地区,其植被恢复已成为国土绿化和生态治理的重点和难点.川西干旱河谷区地形和气候环境复杂,植被恢复限制因子多,关键技术和理论的突破已是瓶颈问题,急需得到进一步解决.本文通过对川西干旱河谷区的形成过程、立地条件、植被演替趋势、存在的问题等进行系统分析,总结历史上该区域植被恢复成功和失败的经验,从恢复植被物种选择、灌溉方式、整地方法、栽植技术、管护等角度提出该区植被恢复适宜模式,为干旱河谷区植被恢复提供理论和实践依据.     

刍议山区公路路堑边坡工程防护与生态防护

公路穿行于河谷山川之间，给人们带来了极大的便利，而劈山开路却使公路两侧的山体、植被和景观遭到极大的破坏。根据安徽省南部山区公路建设中高陡边坡失稳和地质的具体情况，采用了浆砌片石拱型护坡，以加固和稳定边坡；同时根据公路的重要程度结合所在地自然环境、气候条件、土壤类别等，选定边坡生态防护——客土喷播草种，来进行绿化、美化坡面，防止水土流失，达到恢复固工程建设所破坏的生态环境，同时保持生态平衡的效果。     

盐漠带适生植被的筛选及生态恢复模式

通过对准噶尔盆地南缘盐漠带示范基地观测区域内植物群落的物种结构和分布特点进行调查观测及土壤的盐分含量分析,筛选出了红砂、白刺、柽柳、尖叶盐爪爪、无叶假木贼等几种耐盐碱植物,并在试验区内通过人工灌溉(植苗或直播)恢复重建技术进行土壤盐碱改良和生态恢复。结果表明:该区域土壤盐分表聚特征明显,土壤深度增加,轻度盐化土壤面积逐渐增加,重度盐化土壤面积显著减小;通过适生植被的人工灌溉(植苗或直播)恢复重建技术,在试验区内不同生态恢复模式下植物物种增加,地表覆盖度有了显著提高,对绿洲盐碱地的植被恢复起到一定的作用,为绿洲生态重建及进一步开发利用提供选择和对策。     

金沙江干热河谷气候下滨江植物选择及应用——以龙川江元谋县城区段为例

正人类自古就有逐水而居,择水而憩的习惯。时至今日,大量人口集聚的城市都是依水而建。滨水地带独特的风貌,始终具有强大的观赏吸引力。而在受干热气候影响下的金沙江干热河谷地带,植被极为稀疏,大多数为低矮、多刺的旱生型灌丛。本文以龙川江元谋县城区段滨江绿化带为例,探讨在干热河谷气候下,滨江植物的选择原则及适合干热河谷地区生长的主要园林植物,对干热河谷地区城市园林化建设具有重要意义。     

金沙江干热河谷地区传统生土民居夏季物理环境研究

民居是传统文化的重要组成部分。在乡村振兴的背景下,如何保留其特色风貌并提升居住环境品质,是近年来学界关注的热点话题。金沙江流域历史文化源远流长,其河谷地带的生土民居独具特色,但随着经济的发展,许多民居已呈空心化。本文通过对金沙江干热河谷地区传统生土民居进行现场调研和测试,总结了该地区传统牛土民居的生态特性,并根据当地的文化和自然条件提出了一些环境提升的措施。研究可为该地区传统生土民居的更新与发展提供有益的参考。     

山区公路设计中边坡生态防护与植被恢复措施的探讨

主要对山区公路设计中边坡生态防护与植被恢复措施进行分析,以通入某旅游景区的一条公路为例,分别对边坡生态防护的规划设计、植被选择、方案实施进行重点分析,以期为相关山区公路边坡生态防护设计提供一定的参考。     

百花山公路边坡植被恢复与重建效果分析

北方地区干旱石质边坡的植被恢复一直是难题,选择北京百花山自然保护区公路边坡开展植被恢复试验,对试验地土壤的理化性状以及植被恢复情况进行调查,结果表明,采用边坡生态工程技术可大大缩短植被重建时间,高次团粒喷播改进技术优于厚层基质喷附技术,喷播的草本植物第1年生长良好,盖度达100%,第2年下降至80%左右,喷播与移栽的木本植物,萌发率与成活率低,生长慢,形成了一年生种子植物占绝对优势的草本群落,而当地自然恢复的灌丛,结构合理,景观效果好,建议植被重建应以地带性植物群落为目标,以乡土植物为主,合理搭配植物种类,保证建群种的良好生长,加强后期养护工作.     

废弃采石场生态恢复与景观重建研究进展

裸露的岩石、稀少的植被、大量的水土流失,废弃采石场的这些景象触目惊心,人类大肆开采给原有生态系统与环境景观带来极大程度的破坏,废弃地急需有效的技术与方法来恢复与重建。从废弃采石场特点、国内外废弃采石场恢复与重建概况、恢复与重建的策略、坡面稳定、土壤—植被系统等方面概述,以期为废弃采石场的生态修复与景观重建提供参考依据。     

木渎景区金山采石宕口植被恢复与可持续景观设计

采石宕口植被恢复是一项复杂的生态系统工程,涉及采矿、地貌、环境生态、景观生态、植物等学科内容,采石宕口植被恢复与景观营建应遵循“科学规划、分类指导、因地制宜、经济适用、持续发展”的原则。从研究金山采石宕口植被恢复入手,依据宕口土质条件及采石后的立地条件不同而异,提出了金山采石宕口植被恢复的技术路线、技术措施、植被绿化技术和艺术景观再造方法,可供同类地区参考。     

Estimating sediment yield from a forest road network by using a sediment prediction model and GIS techniques

In forest lands, the stream channels receive the highest amount of sediment during road construction activities due to removal of vegetation cover from road surface, cut-slope, fill-slope, and ditch areas. Sediment delivered from a road section to streams causes serious damages on water resources and aquatic life. Performing revegetation in cut-slope and fill-slope reduce sediment yield from a road section; however, road surface and ditch continue to deliver considerable amount of sediment to the streams. Therefore, accurate prediction of sediment yield from existing road network can be very critical. In order to estimate average sediment yield, several sediment prediction models have been developed based on empirical relationships between various road erosion factors. In this study, average annual sediment yield from a road network to streams in a forest watershed was estimated by using the methodology of a GIS-based sediment prediction model, the SEDMODL model. GIS techniques were used to provide required data layers such as topography, streams, roads, geology, and average precipitation. The results indicated that the SEDMODL model integrated with GIS techniques can assist road managers to estimate total sediment yield quickly and effectively. Besides, critical road sections with high sediment yield potential can be identified and the efficiencies of various sediment control measures can be evaluated for these sections.     

Restoring Dynamic Fluvial Processes in Urban Rivers: Learning from the Aire and Isar Rivers

In process-based restoration, the objective is not to create a complex river form directly; instead, interventions are intended to “prompt” the natural processes to restore such forms. The improvements in ecological conditions are actually made over time by flowing water during floods (using the stream’s energy), and by the growth of riparian vegetation (using incoming solar energy). On the Aire River in Geneva, ecological function was restored to a formerly canalized river by providing the river with an espace de liberté. A grid of channels cut into the valley bottom allowed the river to freely flood, erode its bed and banks, and deposit bars, creating complex surfaces on which riparian vegetation established to support the food web of the riverine ecosystem. The diamond-shaped bits of land left between these channels (“lozenges”) gradually erode and evolve as the river migrates, creating complex channel forms. The Isar River in Munich restoration involved adding coarse sediment load, creating erodible bed and banks in place of formerly rigid boundaries, expanding process space for river migration, erosion, and deposition, and increased human access to the river over 8 km. Since restoration, natural transport of sediment has resulted in deposition of gravel bars, whose forms evolve during floods, supporting diverse habitats. The Isar and Aire Rivers provide compelling examples of processbased restoration meeting 4 criteria for process-based restoration: space, energy, materials, and time. They demonstrate the possibilities of urban river restoration to achieve both ecological and social goals through restoration of fluvial process.     

北京市门头沟区煤矸石堆积地不同恢复方式植被特征及植被恢复方法

调查北京市门头沟区东部自然恢复与人工修复的煤矸石堆积地植被特征,比较分析2种不同恢复方式以及不同恢复年限的样地植被恢复状况。植被调查采用样方法,共统计植物69种,隶属35科63属,其中禾本科、菊科、豆科、蔷薇科为优势科。自然恢复样地植物共25种,隶属17科24属;人工修复样地植物共63种,隶属32科58属。自然恢复群落中臭椿、榆树、荆条的重要值较高,是群落的建群种;人工修复的群落中榆树、油松的优势明显。草本层中猪毛菜、地肤、野古草、紫苜蓿和白莲蒿属于恢复的先锋植物,且在群落中优势地位明显。随着终止排矸年限和植被恢复年限的增加,植物群落物种丰富度将增加;人工修复群落的物种多样性整体高于自然恢复群落。提出煤矸石堆积地适生植物材料的选择原则,通过优势度等指标筛选出符合植被恢复要求的植物材料,构建恢复植被群落模式,并总结出适合煤矸石堆积地的立地条件改良技术和植物种植技术。     

GIS技术在边坡植被防护中的应用

将地理信息系统应用于边坡植被护坡领域,以孝襄高速公路植被生态防护工程为例,将公路的走向、起讫地点、边坡特性、护坡方式、植被情况等在地图上显著地标注出来,形成一张包含所有与公路边坡植被防护情况有关的信息地图。     

柿之木坂集合住宅，东京，日本

这是一个位于东京中心区的住宅综合体。基地紧临一条交通主干道。沿着这条大街的正是在东京常见的沿路景观,中等大小的住宅综合体线性排布着。在基地另一边,是一片在谷地中的独栋住宅区。而在这个基地上,却需要设计一个针对单身人士的工作室公寓。通常,工作室公寓项目需要根据基地形状,设计一个拥有多种类型住宅单元的更高效的平面。因此,每个公寓的体量都决定于其自身的方便性,而不考虑周围环境。     

温泉融化路面冰雪试验及其对路面强度影响研究

川西高海拔地区冬季寒冷,路面冰雪问题严重威胁行车安全。而川西丰富的地热资源给解决路面冰雪问题提供了清洁高效的新方法。以海拔高度4 200 m的雀儿山隧道为例,通过数年监测明确了区域气象与温泉温度变化规律,进而研究了PVC与不锈钢管两种管道引入温泉融化路面冰雪效果及其对路面强度影响。结果表明:与间距24 cm布置的PVC管相比,间距40 cm的不锈钢管试验段路面冰雪融化时间降低了47%,保障了路面在30 h降下12 cm雪的环境中无积雪。与原路面相比,加入不锈钢管后抗压与抗折强度分别提高了 12.7%和11.3%,提高了路面的承载能力。研究成果对于高原和高纬度地区利用温泉消除道路冰雪具有借鉴意义。     

Causes and consequences of desertification in Kuwait: a case study of land degradation

Desertification in Kuwait is a process of environmental degradation under fragile ecological conditions and intensive human activities and the consequences of Gulf War. In Kuwait, very severe desertification prevails, due to increasing formation of new active sandy bodies, deterioration of many areas of natural vegetation cover to less than 10%, and limited water resources for large-scale forage production. Average annual desertified land in Kuwait is estimated to be 285 km². In Kuwait, three indicators of land degradation are encountered. These are vegetation, soil, and surface hydrological changes. Based on field measurements of soil compaction and vegetation changes, in the west Jahra area in the northern part of the country, degradation levels were assessed. Results of these measurements show that the average infiltration rate in compacted soil decreased by 53.8% in comparison with non-compacted soil, while the average soil penetration resistance in compacted soil increased by 154.1% in comparison with non-compacted soil. The bulk density in open sites was 23.4% higher than that in protected sites. The percentage of litter in open sites decreased by 77.3% in comparison with protected sites, while the percentage of total vegetation in open sites decreased by 6.1% in comparison with protected sites. Electronic Publication     

Lowering the outdoor temperature in high-rise high-density residential developments of coastal Hong Kong: The vegetation influence

This paper investigates the impact of on-site variables on the influence of vegetation in lowering outdoor temperature. The study uses six critical on-site variables such as surface albedo, sky view factor, altitude, shrub cover, tree cover and average height to floor area ratio to carry out analysis in five data sets. The climatic parameters and physical characteristics were measured and surveyed, respectively in 216 stations in high-rise high-density residential developments of coastal Hong Kong. The data set is mainly categorised into peak summer clear sky days (PSCS-days), peak summer partially cloudy days (PSPC-days) and late summer days to address the issues related to cloudy sky conditions in Hong Kong. The trend analysis shows that at a lower sky view factor, ranging from 0.1 to 0.25, shrub cover as low as 10–15% in a 1000 m² open area is more effective in reducing outdoor temperature than the same level of tree cover in a location with a higher sky view factor (0.4 or above). The regression models used in this study were able to explain the influence of on-site variables on vegetation in lowering the outdoor temperature within the respective urban settings. In high-rise high-density environments, on-site variables such as sky view factor and altitude have a substantial impact on the influence of vegetation in lowering outdoor temperature. However, off-site variables such as high urban density and anthropogenic heat could negate the behaviour of sky view factor and altitude. The study suggests that increasing the tree cover from 25% to 40% in the pocket parks in coastal area residential developments of Hong Kong could reduce daytime urban heat island intensity (UHI) by further 0.5 °C.     

基于顶极—格局假说的植被修复规划设计途径研究

植被修复是一个具有重要理论与实践价值的热点领域。但在既往研究中,对理论机制与实践应用间的关系描述尚少,植被修复一直未能形成系统的步骤和途径。本研究从植被修复的整体过程出发,首先对顶极—格局假说进行了研究,归纳出顶极—格局假说有8个理论要点;继而通过推导理论要点与植被修复的关系,整合现有的多种技术方法,最终提出了一套具有普适性的植被修复规划设计途径,包含5个步骤:植被修复场地分析、修复时间方案选择、生境修复措施选择、关键修复位置识别、修复监测与评价。     

Vegetation of road verges on an urbanisation gradient in Potchefstroom, South Africa

A vegetation survey of road verges along an urban to rural gradient in the Potchefstroom Municipal Area was conducted. Important applications of these studies include understanding of the role of indigenous (native) and exotic species in the overall synanthropisation of vegetation. The present study forms part of a research programme on spontaneous vegetation in urban open spaces in the North-West Province of South Africa. A numerical classification technique ( ) was used as a first approximation and the classification was refined using Braun-Blanquet procedures. The result is a phytosociological table from which 13 plant communities and seven sub-communities were recognised. Although some of these communities and sub-communities are similar to previously described vegetation types in natural and disturbed areas, most of them were not described before in South Africa. Two ordination scatter diagrams show the distribution of the plant communities along gradients which were related to the depth of the soil water table, habitat type, trampling, soil compaction and percentage of gravel in the soil surface. Similarities between roadside vegetation in this study and those overseas are discussed, as well as the possible role of road verges as dispersal corridors between natural and disturbed areas.