Seven Years of Change Following Liming of Sphagnum Communities in Sector Vii of the Loch Fleet Catchment

In 1986, application of lime within the upper wetland area of sector VII of the Loch Fleet catchment initiated numerous unscheduled small-scale experiments on the vegetation of this heterogeneous terrain. Vegetation changes and erosion were monitored in permanent or relocated plots established in 1987 and 1989 and re-surveyed in 1993, seven years after liming.

The most striking early effect, possibly occurring within a few weeks of lime application, was the death of Sphagnum papillosum carpet in soakways within the 2.5 ha area. Some patches of dead material were washed away, but bare surfaces were generally colonised by vascular plants, notably Juncus bulbosus. Effects in moorland and bog communities with dwarf shurbs were more subtle, involving reduction in Sphagnum cover and expansion of Erica teralix, Molinia caerulea, sedges and Narthecium ossifragum, but little change in the frequency of occurrence of Calluna vulgaris.     

黄河三角洲不同植被类型土壤酶活性的季节变化

黄河三角洲自然保护区的酶活性季节特征一定程度影响了该地植被分布类型,为研究黄河三角洲自然保护区不同植被土壤酶活性的季节特征,分别选取碱蓬(Suaeda salsa)、柽柳(Tamarix chinensis)、芦苇(Phragmites communis)、刺槐(Black Locust)和高粱(Sorghum)5种典...     

盐池封育草场土壤种子库特征及其与植被的关系

封育是退化草场恢复的重要措施之一,封育的效果在一定程度上取决于土壤中种子库的状况。以毛乌素沙地西南缘宁夏盐池县的退化草场为研究对象,采用相似性分析和排序方法对封育和未封育草场土壤种子库的特征及其与地上植被间关系进行了研究,结果表明无论封育区还是未封育区,土壤种子库中的种子主要分布于0～5cm的土层,6～15cm土层的种子数很少;封育区土壤种子库的物种丰富度大于未封育区,物种多样性则表现为H值较大,而D值较小,总体上看封育措施可以提高地上植被和土壤中种子的种类和数量,一些一年生植物、中生植物和盐生植物开始出现在地面或土壤种子库中。地上植被和土壤种子库间的相似性分析结果则表明相同措施同一土层间种子库中等相似,而不同土层间还是存在着一些差异。由于封育措施导致了植被样方的相似性较低,然而土壤种子库间的相似性仍然较高,两者间是否存在着一定程度的滞后效应有待于进一步研究。     

The potential implementation of green infrastructure assessment using high-resolution National Agriculture Imagery Program data for sustainable hazard mitigation

As green infrastructure gets its attention in hazard mitigation, it is necessary to improve general understanding on what makes green infrastructure important for hazard and resiliency research. To better understand how green infrastructure fits with more traditional notions of structural and nonstructural mitigation, this study examines the relationship between green infrastructure and ‘structural and nonstructural’ mitigation approaches for hazard mitigation. Also, this study discusses a new measurement of locational aspects and spatial patterns of green infrastructure by utilizing high-resolution data in urban areas, and its potential implementation in hazard mitigation. Compared to previous research using land-use land-cover datasets, the normalized difference vegetation index (NDVI) utilizing National Agriculture Imagery Program dataset provides an ability to capture green infrastructure in greater detail. A visual comparison suggests that the NDVI data are able to capture and identify more types of ‘green’ land uses in Harris County. The total green infrastructure percentages for Harris County, Texas, based on 1-m high resolution were found to be 61.5% of the area, compared to the 51.5% based on the National Land Cover Database. This study provides support for utilizing high-resolution data to establish guidelines for green infrastructure’s spatial characteristics and sustainable hazard mitigation. The outcomes of this study will be helpful in the strategic planning and implementation of green infrastructure in urban areas with hazard issues.     

河西走廊中部荒漠植被的生态学研究

根据对河西走廊中部荒漠植被的调查，对荒漠植被进行了分类及生态学描述，重点讨论了荒漠植被对改善河西走廊中部农村生态环境的作用，提出了保护和利用荒漠植被的措施及改善生态环境的途径。     

铅锌冶炼厂土壤污染及重金属富集植物的研究

对株洲市铅锌冶炼厂生产区进行了植被和土壤调查。结果表明，该厂土壤污染以镉铅锌(Cd、Pb、Zn)最为严重，尤其是重金属镉在土壤中含量超过背景值高达208倍，分析原因主要是由于大气尘降和雨水淋洗等使得污染加重。实验采集并分析测定了9种植物中重金属富集量，首次报道了土荆芥是一种铅超富集植物，其体内Pb质量分数高达3888mg／kg。另一种植物商陆能大量富集镉，具有地下部向地上部转运能力强、生物量大、富集总量高的特点，有很大研究价值和应用潜力。另外，荨麻对Zn有较强富集能力，这3种植物可分别用于铅、镉和锌等3种重金属污染土壤的植物修复。     

台湾泥岩地区不同刺竹林景观下之土壤与植被变异

台湾西南部泥岩恶地,由于其特殊之土壤,地力流失消耗与区域微气候型态之间的因果循环,在水土保持与景观上形成不易植生绿化的地区及特殊之世界地形。泥岩地区之不同刺林林相之土壤,其林相皆伐后复层植被区土壤性质变异高于其它位置,而其它区之土壤理化性质在时间及空间上之变异不大,可明显区分林相不同之显著差异。不同林相对泥岩地浅层土壤(0~20cm)理化性质的差异,以植物营养元素与植生覆盖因子可充分说明(约占变异范围之62%)。泥岩试区区中移动性物质(交换性钙、钠与镁)明显较少出现在复层林相处区,而易出现于淋洗、冲蚀量较大之刺林相保留区与隔丛择伐区。长效性植物营养元素因子(pH值与有效性磷),因长时间之林相不同,使其较明显趋于复层林相区堆积,并影响地表植生之种类、分布与覆盖情形。0～20cm土壤性质的分布和离子间的移动特性有关,移动性高的钠、镁离子会在冲蚀量高之区域出现,20～40cm土壤性质的分布则和土壤中之母质与植生有关并与因素分析结果相似,其次为可移动性离子的影响,且应用地理统计印证土壤性质在空间之变化,其分布确实与不同林相位置有关,即植生营养元素(pH值、有效性磷)大都朝向复层植被区之趋势。典型相关分析结果,地表覆盖度与入侵植物数量两变量主要系透过第一个典型因素与第二个典型因素而影响到复层植被区之pH值、有机质等土壤理化性质。     

城市绿化中选择净化空气的植物配植

文章叙述了在城市绿化中选择净化空气的植物配植的方法、原则，介绍了几种对大气污染吸收净化能力强的植物种类，和室内选择净化空气的花草。     

Conservation of Vascular Epiphyte Diversity in Mexican Coffee Plantations

Abstract:  Coffee plantations have replaced many lower-montane forests in the Neotropics, and ongoing intensification is converting traditional polycultures with a variety of shade trees to plantations with no or monospecific shade trees. To evaluate the impact of coffee cultivation on epiphyte diversity, I surveyed vascular epiphytes on shade trees in nine different coffee plantations and compared records with those in four natural forests in central Veracruz, Mexico. Eighty-nine species occurred in coffee plantations, and 104 species occurred in natural forests. The number of epiphytic species in traditional polycultures with old shade trees, mostly of the genus Inga , was similar to that in forests, but plantations with small trees and sparse shade hosted fewer epiphytes than those with large trees. Epiphyte communities were, however, more homogeneous in coffee plantations than in forests, possibly because of a drier microclimate and the lack of large and long-lived trees. These results demonstrate the value of traditional polycultures for epiphyte diversity, show the importance of conserving large shade trees, and suggest that these coffee systems may not be suitable for all epiphytes.