不同绿地空气负离子比较研究——以浙江富阳市洞桥镇为例

空气负离子是衡量空气质量的重要指标之一,试验测定富阳市洞桥镇不同绿地空气负离子浓度,研究其生态效应变化。结果表明,以高大乔木为主的城郊绿地空气负离子浓度较高,生态效应显著。因此,植物景观设计上要遵循近自然森林群落理念,注重以高大乔木为主的森林绿地建设,改善城镇生态环境质量,提高城镇生活品质。     

居住区绿地植物群落结构调查与生态效益评价——以浙江临安市为例

通过对临安市3个新建居住区绿地植物群落多样性现状的调查,分析样地内植物的组成、群落的层次结构特征、生物多样性,以及居住区园林植物群落多样性存在的问题,得出结论:从群落的多样性角度来看,Simpson指数:林水山居>春天小区>筑境小区,林水山居的植物种类最为丰富,乔灌草的搭配也比较合理。从生态效益评价来看,负离子浓度是评价空气质量的重要指标,所测数据表明,在外界影响因素相同的情况下,湿度越高,空气负离子浓度越大,生态效益也相对较好,负离子浓度春季要高于冬季,整体上春天小区>林水山居>筑境小区,3个居住区的空气清洁程度都为清洁。根据对临安居住区绿地植物群落结构的调查结果,提出群落优化改造建议。     

臭氧发生器在低乙烯果品保鲜中的应用

XF法即臭氧和负离子气体保鲜法,人们习惯称为臭氧保鲜法。1988年我们用本厂制造的CYF—7型程控臭氧发生器对苹果、梨、葡萄、西瓜进行了试验。用空气做原料静态产臭氧量2000mg/h,负离子10~7个/cm~3,用纯氧做原料动态(循环气流)产量提高一倍以上。一台可控50—100吨,日耗电量0.5—1 。采用方法是周期性高低浓度臭氧循环冲击处理,由     

空气负离子时空变化及保健功能研究进展

综述了近年来空气负离子的研究进展,主要从空气离子的评价标准、空气负离子的时间变化、空气负离子的空间变化和空气负离子的保健功能4个方面介绍了空气负离子的研究成果.空气负离子浓度夏秋季节最高,冬春季节较低；早晨和下午各有一个峰值,中午较低；中海拔地区和近水区域空气负离子浓度较高；空气负离子具有促进睡眠,预防疾病等多种功效.     

菏泽市城市绿地植物多样性保护规划研究

选取菏泽市中心城区具有代表性的公园绿地、附属绿地和防护绿地,应用物种丰富度指数(S)、多样性指数(Shannon-Wiener指数)、优势度指数(Simpson指数)和Pielou均匀度指数(E)对不同绿地植物群落进行研究分析,并对菏泽市其它绿地植物多样性进行实地调查研究。结果表明:菏泽市城市绿地建设中应以塑造"平原森林城市"为目标,注重应用乡土树种和模拟自然群落,研究并总结出典型植物群落的树种配置和城市绿地植物配置比例,提出树立大城市观念,建立城乡连续的植物多样性保护体系。     

城市不同居住区绿地生态效应评估

以哈尔滨市4处代表性居住区与龙塔广场(对照样点)为研究对象,采用隶属函数分析法,于2019年7、8月,测定该4处居住区绿地与龙塔广场的噪音量、空气负离子(negative air ion,简称NAI)浓度和滞尘量3项生态指标,研究了不同居住区中绿地的生态效应。结果表明:在不同月份、一天内不同时段,不同居住区绿地与龙塔广场绿地各项生态指标相比,绿地减噪量、NAI浓度增量、滞尘量的变化趋势不尽相同。居住区绿地减噪量(4.15、5.42、2.55、5.50 db)、NAI浓度增量(187、139、170、215个·cm^-3)>龙塔广场绿地(2.44 db、89个·cm^-3),龙塔广场绿地的滞尘量(2.29 mg·m^-3)>居住区绿地(2.09、1.41、2.59、1.80 mg·m^-3)。对于不同月份生态效应隶属函数分析中,不同环境中绿地生态效应有所不同,各居住区与广场绿地7月总体生态效应(0.20、0.22、0.15、0.30、0.07)>8月总体生态效应(0.19、0.16、0.13、0.29、0.11×10-2)。居住区绿地的生态效应(0.20、0.19、0.14、0.30)>龙塔广场绿地(0.03),其中远大都市绿洲居住区的绿化生态效应最佳(0.30)。因此,居住区绿地绿化率、植物多样性、配植形式、乔灌比等生态指标可显著影响其生态效应。     

木香薷群落负离子及PM_(2.5)浓度的时空变化及其影响因素

以木香薷为试材,对开花进程中、一天中不同时间及仪器进气口距植株顶部不同高度处的空气负离子、PM_(2.5)浓度、气象因子进行测定,以期探究芳香植物木香薷群落负离子及PM_(2.5)浓度的时空变化特征及其影响因素。结果表明:开花进程中木香薷群落负离子浓度由低到高的变化顺序依次为初花期盛花期末花期;开花进程中PM_(2.5)浓度由高到低依次为初花期盛花期末花期;木香薷群落负离子浓度的最高值出现在17:00,最低值出现在15:00;PM_(2.5)浓度最高值出现在11:00,最低值出现在17:00;仪器进气口距植株顶部15 cm处空气负离子浓度高于45 cm处的浓度,二者相差90.5 ion·cm~(-3),而不同位置处的PM_(2.5)浓度差值仅0.6μg·m~(-3),即群落负离子浓度受位置变化影响较大,PM_(2.5)浓度则受影响较小;木香薷群落负离子浓度与温度、光照强度均呈极显著负相关,而与湿度呈极显著正相关,且直线回归表明负离子浓度与各气象因子的相关性从强到弱依次为湿度温度光照强度;PM_(2.5)浓度与温度呈显著负相关,与湿度、光照强度均呈正相关,且与湿度的相关性达到极显著水平。     

关于屋顶绿化微环境的调查研究

以杭州市隽维中心屋顶绿化为对象,分别对温度、湿度、CO2浓度、空气负离子浓度进行对比观测,结果表明,不同的植物配置模式会影响到建筑周围的微环境,从优至劣排序:乔灌草复层式绿地草坪绿地廊架硬质园路。此排序在夏冬两季差异尤其明显。     

杭州下沙园林植物适应性调查

通过对下沙绿地中的乔木、灌木、藤本3类树种进行调研,总计有56种乔木、74种灌木、10)种藤本,对种植3年以上的树种进行了生长性分析,得出生长势较好的乔木35种,灌木44种,藤本9种,以期对下沙园林绿化树种的种植提供理论的依据。     

天津典型绿化树种提供空气负离子研究

对天津市4个不同地点(昆仑桥、水上公园、杨柳青庄园和市区空旷地)林木的空气负离子浓度日变化和年变化进行测定,并分析了空气温湿度等环境因素对其影响。结果表明:空气负离子浓度日变化基本呈先增大而后减小的趋势,其最大值多出现在中午左右,不同地点略有不同;空气负离子浓度季节变化趋势基本为夏季春季秋季,最大值出现在7月;不同地点空气负离子浓度变化趋势与温湿度变化趋势一致,呈正相关关系;水上公园的空气质量最清洁,市区空旷地质量最差。林木可以提供空气负离子,从而达到净化空气的目的,有利于身体健康。因此,城市建设中应加强植被绿化。     

Forest conservation and land development in Puerto Rico

In the Caribbean island of Puerto Rico, rapid land-use changes over the past century have included recent land-cover conversion to urban/built-up lands. Observations of this land development adjacent to reserves or replacing dense forest call into question how the changes relate to forests or reserved lands. Using existing maps, this study first summarizes island-wide land-cover change between 1977-78 and 1991-92. Then, using binomial logit modeling, it seeks evidence that simple forest cover attributes, reserve locations, or existing land cover influence land development locations. Finally, this study quantifies land development, reserve protection and forest cover by ecological zone. Results indicate that 1) pasture is more likely to undergo land development than shrubland plus forest with low canopy density, 2) forest condition and conservation status appear unimportant in that development locations neither distinguish between classes of forest canopy development nor relate to forest patch size or reserve proximity, and 3) most land development occurs in the least-protected ecological zones. Outside the boundaries of strictly protected forest and other reserves, accessibility, proximity to existing urban areas, and perhaps desirable natural settings, serve to increase land development. Over the coming century, opportunities to address ecological zone gaps in the islands forest reserve system could be lost more rapidly in lowland ecological zones, which are relatively unprotected.This revised version was published online in May 2005 with corrections to the Cover Date.     

A large-scale fire suppression edge-effect on forest composition in the New Jersey Pinelands

Broad scale ecological edge-effects are most likely common in urbanized landscapes prone to wildfire, but most edge-effect studies have focused on fine scale processes such as shade tolerance and seed dispersal. Evidence has suggested a shift from pine dominated to oak dominated forests at the interface of developed land and natural areas in the Pinelands of New Jersey with the presence of a large edge-effect due to fire suppression. The goal of this study was to assess the location, magnitude and mechanism of the shift from pine to oak cover focusing on distance to human-altered land as the driver of fire suppression and forest composition changes. Overall, fire frequency and upland pine cover decreased sharply closer to human-altered land and affected up to 420 m of adjacent upland forest. Other factors, such as prescribed fire and wetlands configurations may play a role in the interior forest dynamics, but trends toward lower upland pine forest cover and higher upland oak cover near human altered were dominant. The areal summations of distance from altered land and the use of percent change thresholds for determining the scale and magnitude of large scale ecological edge-effects could be useful to managers attempting to maintain or restore forest types in areas of high wildland–urban interface.     

4种纯林空气负离子浓度研究

利用负离子仪对上海市松江区中央公园的4种纯林内的空气负离子浓度进行测定,并通过比较分析,得出如下结果：桂花、紫叶李、蚊母树纯林在5月和7月份的空气负离子浓度日变化曲线呈双峰型,石楠呈单峰型;在6月和8月份紫叶李、蚊母树和石楠纯林日变化曲线相似,几乎平行;不同纯林日平均负离子浓度有差异,相关性分析表明,纯林内的空气负离子浓度与温度和相对湿度的几乎无显著相关性,为合理利用负离子资源提供一定依据。     

长兴县煤山镇绿地系统规划研究

城市绿地系统是城市景观的自然要素和社会经济可持续发展的基础，是城市生态环境的主体。以煤山镇绿地系统规划为例，分析快速城市化背景下小城镇的绿地建设的问题。提出构建稳定镇域大环境生态绿地格局、发展森林式绿地、体现地域文脉及现实多功能复合的小城镇绿地系统规划思路。     

青山湖不同植物群落空气负离子效应评价

以临安市青山湖湿地公园典型植物群落常绿阔叶林、香樟林、池杉林及人工林为研究对象,研究4种不同植物群落空气负离子效应及其空气清洁度的比较。研究结果表明,不同植物群落空气负离子浓度大小排序为常绿阔叶林〉人工林〉香樟林〉池杉林,常绿阔叶林空气负离子浓度最高,环境调节功能最强,其对改善湿地公园环境质量发挥着重要的作用。     

Landscape characteristics affecting streams in urbanizing regions of the Delaware River Basin (New Jersey,New York,and Pennsylvania,U.S.)

Widespread and increasing urbanization has resulted in the need to assess, monitor, and understand its effects on stream water quality. Identifying relations between stream ecological condition and urban intensity indicators such as impervious surface provides important, but insufficient information to effectively address planning and management needs in such areas. In this study we investigate those specific landscape metrics which are functionally linked to indicators of stream ecological condition, and in particular, identify those characteristics that exacerbate or mitigate changes in ecological condition over and above impervious surface. The approach used addresses challenges associated with redundancy of landscape metrics, and links landscape pattern and composition to an indicator of stream ecological condition across a broad area of the eastern United States. Macroinvertebrate samples were collected during 2000–2001 from forty-two sites in the Delaware River Basin, and landscape data of high spatial and thematic resolution were obtained from photointerpretation of 1999 imagery. An ordination-derived ‘biotic score’ was positively correlated with assemblage tolerance, and with urban-related chemical characteristics such as chloride concentration and an index of potential pesticide toxicity. Impervious surface explained 56% of the variation in biotic score, but the variation explained increased to as high as 83% with the incorporation of a second land use, cover, or configuration metric at catchment or riparian scales. These include land use class-specific cover metrics such as percent of urban land with tree cover, forest fragmentation metrics such as aggregation index, riparian metrics such as percent tree cover, and metrics related to urban aggregation. Study results indicate that these metrics will be important to monitor in urbanizing areas in addition to impervious surface.     

Spatial patterns of a subtropical,coastal urban forest: Implications for land tenure,hurricanes, and invasives

Spatial patterns of tree structure and composition were studied to assess the effects of land tenure, management regimes, and the environment on a coastal, subtropical urban forest. A total of 229 plots in remnant natural areas, private residential, public non-residential, and private non-residential land tenures were analyzed in a 1273 km² study area encompassing the urbanized portion of Miami-Dade County, USA. Statistical mixed models of structure, composition, location, and land tenure data were used to analyze spatial patterns across the study area. A total of 1200 trees were measured of which 593 trees (49%) were located in residential areas, 67 (6%) in public non-residential areas, 135 trees (11%) in private non-residential areas, and 405 (34%) in remnant, natural areas. A total of 107 different tree species belonging to 90 genera were sampled. Basal area in residential land tenures increased towards the coast while private residential land tenures and natural areas had higher species diversity than non-residential areas. Tree height, crown light exposure, and crown area might indicate the effects of past hurricane impacts on urban forest structure. Land tenure, soil types, and urban morphology influenced composition and structure. Broadleaf evergreen trees are the most common growth form, followed by broadleaf deciduous, palms, and conifers. Exotic tree species originated mainly from Asia and 15% of all trees measured were considered exotic-highly invasive species. We discuss the use of these results as an ecological basis for management and resilience towards hurricane damage and identifying occurrence of invasive, exotic trees.     

The impacts of historical land-use and landscape variables on hollow-bearing trees along an urbanisation gradient

Hollow-bearing trees provide habitat for diverse taxonomic groups and as such they are recognised for their importance globally. There is, however scant reference to this resource relative within urban forest patches. The functional ecology of habitat remnants along an urbanisation gradient plays an important ecological, social and economic role within urban landscapes. Here we quantify the impacts of urbanisation, landscape, environmental, disturbance (past and present) and stand variables on hollow-bearing tree density within urban forest patches. This was undertaken by surveying 45 forest patches on the Gold Coast, south-east Queensland, Australia. Sites were categorised as; urban, peri-urban or rural along an urbanisation gradient, with an additional five control sites. Historical logging practices were found to be the driving factor influencing hollow-bearing tree density along the urbanisation gradient; while the impacts of urbanisation itself are not as yet discernible. These findings highlight the significance of incorporating historical land use practise into current and future urban planning, as these will have continuing impacts on remaining urban biodiversity values. These findings, will benefit natural resource managers and urban planners when making decisions about where and how best to manage for hollow-bearing trees along urbanisation gradients.     

90 years of forest cover change in an urbanizing watershed: spatial and temporal dynamics

Landscape structure in the Eastern US experienced great changes in the last century with the expansion of forest cover into abandoned agricultural land and the clearing of secondary forest cover for urban development. In this paper, the spatial and temporal patterns of forest cover from 1914 to 2004 in the Gwynns Falls watershed in Baltimore, Maryland were quantified from historic maps and aerial photographs. Using a database of forest patches from six times—1914, 1938, 1957, 1971, 1999, and 2004—we found that forest cover changed, both temporally and spatially. While total forest area remained essentially constant, turnover in forest cover was very substantial. Less than 20% of initial forest cover remained unchanged. Forest cover became increasingly fragmented as the number, size, shape, and spatial distribution of forest patches within the watershed changed greatly. Forest patch change was also analyzed within 3-km distance bands extending from the urban core to the more suburban end of the watershed. This analysis showed that, over time, the location of high rates of forest cover change shifted from urban to suburban bands which coincides with the spatial shift of urbanization. Forest cover tended to be more stable in and near the urban center, whereas forest cover changed more in areas where urbanization was still in process. These results may have critical implications for the ecological functioning of forest patches and underscore the need to integrate multi-temporal data layers to investigate the spatial pattern of forest cover and the temporal variations of that spatial pattern.