Interpatch movements in spatially structured populations: a literature review

We used published data of individuals moving among habitat patches to answer questions pertaining to frequency of interpatch movements and subsequent effects on population dynamics. A review of 415 published articles produced data for 89 species-system combinations where movements were recorded in sufficient detail to include in our analysis. The percentage of individuals in a population that moved among habitat patches ranged from 0.00 to 93.00%, with a mean of 16.84%. Scaling this statistic by generation time yielded a mean movement rate of 15.45 ± 3.27% per generation. The relatively low movement rates suggest that subpopulations, except those of invertebrates, should not be highly integrated. Less than half of the empirical studies reported on the population effects of interpatch movement. Of these, thirty-three studies yielded population effects on 34 individual species in 45 species-systems. They reported movement having a positive effect 28 times, a negative effect twice and a neutral effect 14 times. Despite its importance, relatively few studies document rates of interpatch movement and far fewer determine population level consequences of these movements. This deficiency limits our ability to understand the dynamics of spatially structured populations and apply that knowledge to conservation efforts.This revised version was published online in May 2005 with corrections to the Cover Date.     

Effects of urban parks on the local urban thermal environment

Air temperatures in and outside of 60 parks in Taipei city were surveyed to study the effect of different urban parks on their surrounding thermal gradients. Results suggest that the factors governing the temperature of park surroundings are not identical to those of park interiors. Air-temperature gradients surrounding urban parks are influenced by both the horizontal transport of cool or warm air mass above parks and the evapotranspirative air-parcels from trees, creating a cool island larger than the boundaries of cool-island parks, a heat-island larger than the boundaries of strong heat-island parks, and a cool-ring outside weak heat-island parks. Such horizontal air movement is not easily detected using remotely sensed data. During daytime, the thermal environment within a park is dominated by the amount of solar input absorbed by unshaded paved area, which, when strong, can overflow to increase the temperatures of park surroundings; at night, despite park trees causing a warming effect inside parks, park surroundings are cooled by horizontal flow of evapotranspirative air-parcels from park trees. In business and other districts used mostly during daytime, it is recommended that parks and other open spaces be designed with less than 50% paved area and at least 30% trees, shrubs, and other shadings. In residential districts that are used mostly during nighttime, parks and other open spaces are recommended to be designed with more trees. Night irrigation, a measure commonly recommended for the conservation of water, is also recommended to further enhance this nighttime cooling.     

园艺植物在居室环境中的运用

居室环境是指人们生活、工作和休憩的室外庭院和室内环境。随着工业化的发展,大量使用人造建材进行美化和装饰工作、生活环境,使人们的居室环境污染也成为值得关注的重要议题。尤其对城市居民来讲,每天平均大约80%～90%以上的时间是在各种室内环境中度过的,居室环境成为直接影响人们生活的关键。园艺植物在居室中的各种运用,不仅美化居室环境、净化空气、减轻污染、改善居室理化条件,还能使生活环境增添生命的气息,增进身心健康。     

试论城市绿化中乡土植物与外来植物的互补性

在对城市绿化建设中的乡土植物与外来植物选用的观点论述或实际操作中,往往偏执其一.本文在客观论述乡土植物与外来植物各自特点的基础上,系统明确地对两者在城市绿化中有机结合(优势互补)的必要性及可行性方面进行了论述.     

榆林市城市绿地景观植物与配置设计

通过对榆林市绿地景观中常用植物资源的分析,探讨了城市绿地植物配置设计原则,应根据植物的生物学特性科学地、有机地、合理地搭配应用,以期优化榆林市绿地景观植物与配置设计。     

彩叶植物在南宁道路绿化中的应用调查

对南宁市22条主要城市道路绿化中的彩叶植物进行调查,结果表明,南宁市现有道路绿地主要应用的彩叶植物共有16科、31种,其中乔木4科、9种;灌木9科、12种;草本6科、10种.根据色彩在叶面上的分布可将其分成单色叶类、双色叶类、斑叶及花叶类、镶边类和彩脉类.文章在研究结果基础上,针对目前南宁市道路绿化彩叶植物应用存在的问题,提出相应的建议与对策.     

Landscape influence on biophony in an urban environment in the European Alps

Landscape Ecology - Biophony is the acoustic manifestation of biodiversity, and humans interact with biophony in many ways. However, quantifying biophony across urban landscapes has proven...     

3种入侵植物乙醇提取物对椰子木蛾的杀虫活性研究

以椰子木蛾(Opisina arenosella Walker)3龄幼虫为靶标,测定了3种入侵植物乙醇提取物的杀虫活性。结果表明:同一浓度下的马缨丹(Lantana camara)、薇甘菊(Mikania micrantha)和假臭草(Eupatorium catarium)3种入侵植物乙醇提取物,随着时间增加校正死亡率均不断提高;72 h时,浓度为40 mg/m L的3种植物乙醇提取物的杀虫活性均超过50%;3种植物乙醇提取物对椰子木蛾3龄幼虫的LC50最小的是马缨丹,其次是薇甘菊和假臭草,说明椰子木蛾对马缨丹最为敏感;采用气相色谱-质谱(GC-MS)联用法分析鉴定了马缨丹提取物中的17种化学成分。     

The re-emergence of indigenous forest in an urban environment, Christchurch, New Zealand

Christchurch, the second largest city in New Zealand is a planned city on a coastal plain on the east coast of the South Island. The birth of the city and the subsequent century of development was characterised by colonial values and tree and garden planting with familiar European species along with those from Australia, North America, and eventually all other continents. The image of an “English garden city” with classical parks of oaks and willow-lined rivers became the accepted norm and the way in which the city has been promoted to potential tourists. Gardening is one of the top two recreational activities and exotic species greatly outnumber native species in the flora and in gardens. This has had serious consequences for the highly fragmented and degraded indigenous vegetation and its co-adapted wildlife. A few hardy indigenous species continued to regenerate through this period, but since the 1970s, there has been a progressive change of attitude and interest in reclaiming the natural heritage of the city, manifest in widespread private and public planting of indigenous species and active habitat restoration. In this article we examine the indigenous and exotic shrub and tree components of the Christchurch flora as planted street trees, in domestic gardens, and in parks. We also present data on shrub and tree regeneration in parks and domestic gardens in the city. Indications are that the more sensitive, less intrusive management of urban environments, combined with the greater density of indigenous seed sources, has allowed regeneration of a wide range of indigenous species across a broad spectrum of habitats – from neglected gardens to pavement cracks to exotic plantations. This is despite the competition from the prodigious seed banks and density of exotic trees, shrubs, and ground covers and albeit minimal impacts of introduced browsing and seed eating mammals. If the present trends continue through appropriate management and facilitation, these tentative signs of native forest regeneration should eventually proliferate into a sustainable mixed origin urban forest that resurrects and preserves the natural character of the region.     

Building shade affects light environment and urban greenery in high-density residential estates in Singapore

Urban green spaces are an important component of the urban ecosystem of cities as they provide a range of ecosystem services that contribute to sustainability and livability of urban areas. The extent to which such services are provided is influenced by limitations on biological processes that underpin such ecosystem services. A poorly understood limitation in the urban environment is the effects of shade created by buildings on the adequacy of photosynthetically active radiation (PAR) for plant growth. We examined the effects of building shade in high-density, high-rise residential estates in Singapore on the level and distribution of PAR, and how PAR might in turn be correlated with growth of plants in community green spaces nested within these estates. Our estimates showed that high-rise and high-density buildings reduced daily PAR by almost 50% when compared to fully exposed conditions. The reduced PAR levels were correlated with lower vegetative and reproductive growth of several species of shrubs, and increased slenderness of two tree species. The shade environment created by buildings was differentiated from shade under vegetation canopies by longer periods of high instantaneous PAR during a diurnal cycle. There was also evidence of higher red to far-red ratio in the spectral composition of PAR. We suggest that an understanding of the spatial and temporal characteristics of PAR is necessary for appropriate selection of plants, particularly to match daily PAR received on site to daily light integral requirements of plants for improved delivery of ecosystem services.     

Effects of street landscape planting and urban public parks on dwelling environment evaluation in Japan

In this paper, we use data from 12 metropolitan cities in Japan to investigate the effects of street landscape planting and urban park areas on land prices, and estimate the magnitude and saturation levels of these effects, as well as examining the current level of planting and park areas in these cities. The empirical results imply that increasing the street landscape planting ratio improves the dwelling environment, in terms of both the magnitude and saturation level of the planting ratio, while increasing the amount of urban park area does not.     

Growth responses of some greenhouse plants to environment. I. Experimental techniques

A system for continuous measurement of net photosynthesis of small stands of greenhouse plants in an almost air-tight cabinet is described. The accuracy of control of the CO₂ concentration in the cabinet is within ± 1% of the desired value. The control of air temperature is within ± 0.2°C and the relative humidity within ± 2% from the adjusted value. The amount of CO₂ used in photosynthesis is measured by the number of injections of controlled volumes of CO₂ in a specific time interval.A system for soil temperature regulation is described. In the range from 5 to 35°C, the accuracy of control of the soil temperature is usually within ± 0.5°C from the desired value. At high solar irradiance, however, the temperature may rise about 2°C at the lower, and somewhat less at the higher, soil temperatures.Results from preliminary experiments with roses and chrysanthemums are presented.     

剖析吕家村城乡一体化建设中景观环境规划

通过对吕家村城乡一体化建设规划中景观环境规划的阐述,透析通过城乡一体化建设来加快村庄内造林绿化工作步伐,同时牢固树立"环境意识"和"资源意识",加大农村村庄环境建设,加大对村容村貌的整治,提高吕家村的绿化率,提升吕家村的村镇品味,改善农村生活环境,改善局部小气候,带动天水旅游产业的发展。     

A ground-based comparison of nutrient delivery technologies originally developed for growing plants in the spaceflight environment

A ground-based comparison of plant nutrient delivery systems that have been developed for microgravity application was conducted for dwarf wheat (Triticum aestivum L. 'Yecora Rojo') and rapid-cycling brassica (Brassica rapa L. CrGC#1-33) plants. These experiments offer insight into nutrient and oxygen delivery concerns for greenhouse crop production systems. The experiments were completed over a 12-day period to simulate a typical space shuttle-based spaceflight experiment. The plant materials, grown either using the porous-tube nutrient delivery system, the phenolic foam support system, or a solidified agar nutrient medium, were compared by plant-growth analysis, root zone morphological measurements, elemental composition analysis, and alcohol dehydrogenase enzyme activity assay. The results of these analyses indicate that the porous tube plant nutrient delivery and the phenolic foam systems maintain plant growth at a higher level than the solidified agar gel medium system. Root zone oxygenation problems associated with the agar system were manifested through biochemical and morphological responses. The porous tube nutrient delivery system outperformed the other two systems on the basis of plant growth analysis parameters and physiological indicators of root zone aeration. This information is applicable to the current crop production techniques used in greenhouse-controlled environments.     

The impact of urban expansion on the regional environment in Myanmar: a case study of two capital cities

Context

This study examines the spatio-temporal patterns of urban expansion for Yangon and Nay Pyi Taw, the former and new national capitals of Myanmar, and its impact on the regional environment between 2000 and 2013.

Objectives

The objective is to examine different driving forces of urban expansion for Yangon and Nay Pyi Taw, and their environmental consequences during Myanmar’s transitional economy.

Methods

Classified time-series Landsat images are used to evaluate urban expansion processes. Environmental parameters being evaluated in this study include five sets of remotely sensed MODIS land products that are land surface temperature (LST), percent tree cover (PTC), evapotranspiration (ET), terrestrial ecosystem net primary productivity (NPP), and aerosol optical depth (AOD). A time-series trend analysis technique is used to examine the environmental consequences.

Results

The built-up areas in Nay Pyi Taw and Yangon exhibit exponential and polynomial increase, respectively. A 1% increase of built-up area could potentially cause an increase of daytime LST of 0.7 °C, a PTC loss of 2.3%, a decrease in NPP of 34.3 kg/m², and an ET decrease of 42.2 mm for Yangon. Similarly, for Nay Pyi Taw, a 1% increase in built-up area could potentially cause a daytime LST increase of 0.3 °C, a nighttime LST increase of 0.06 °C, a PTC loss of 2.5%, a decrease in NPP of 15.1 kg/m², and a decrease of 19.2 mm ET. No significant change was observed for AOD for either city.

Conclusions

Both cities have experienced extensive urban expansion but with different spatial and temporal characteristics, and their effects on the regional environment are different. Urban expansion of Nay Pyi Taw mainly was government-induced municipal infrastructure development. Yangon’s expansion is mainly caused by population pressure and migration from rural areas. The urban expansion in Yangon was mainly due to reconstruction and renovation, as well as infill development during the study period.

     

Contrasting impacts of invasive plants and human-altered landscape context on nest survival and brood parasitism of a grassland bird

Context

Humans have altered grasslands in recent decades through crop conversion, woody encroachment, and plant invasions. Concurrently, grassland birds have experienced range-wide declines. Studies have reported effects of plant invasions and land conversion on nest ecology, but few have assessed relative impacts of these changes.

Objectives

We compared impacts of invasive plants and landscape context on nest survival of a grassland songbird, the dickcissel (Spiza americana). We also compared effects on parasitism by brown-headed cowbirds (Molothrus ater) and tested whether parasitism affects survival.

Methods

From 2013–2016, we monitored 477 dickcissel nests. We measured nest-site vegetation (including woody plants, tall fescue Schedonorus arundinaceous, and other invasive grasses) and measured landscape context at broad scales.

Results

Nest survival declined with increasing tall fescue cover at nest sites, and parasitism was more common at nests with greater fescue and woody cover. Some evidence suggested a negative effect of row-crop cover within 1000 m on nest survival, but no landscape patterns unambiguously affected survival. Woodland cover and wooded-edge prevalence were associated with reduced parasitism risk. Parasitized nests had smaller clutches, failed more frequently, and produced fewer fledglings than non-parasitized nests.

Conclusions

Determining the impacts of invasive plants and other anthropogenic changes on grassland birds will aid in prioritizing management to improve habitat quality. Our results indicate that optimizing landscape context around habitats may not affect dickcissel nest survival strongly, except perhaps through effects on parasitism. In contrast, controlling tall fescue and shrubs within grasslands could benefit birds by increasing nest success and reducing parasitism.

     

Distribution of three indigenous fern species along a rural–urban gradient in the city of Angers, France

The preservation of wild plants and animals in urban environments can be a good means to meet the demand for natural areas for recreational purposes. However, the impacts of urbanisation on native species distribution are poorly studied. A city environment has high impact on vegetal community dynamics, especially in terms of climate modification, level of perturbationand pattern of dispersion. We chose to study the three indigenous species of the genus Polypodium that are known to grow in a wide range of habitats, including forest and urban environments, and exhibit a priori a strong ability for dispersal. The aim of the study was to evaluate the factors involved in the Polypodium species distribution and to determine whether this distribution was influenced by the rural–urban gradient. The distribution of the three fern species was investigated in the city of Angers (France) at two levels: for a park (urban woodland) and for the whole city. A contrasted distribution of the three Polypodies has been recorded and shows a rural–urban gradient. This can be explained by the ecology of each species and some biological traits. It means that differences in the spatial structure of the city lead to particular patterns of distribution for these plants. Thus, preserved indigenous vegetation may be influenced in its species composition by the surrounding urban development.     

Growth responses of some greenhouse plants to environment. III. Design and function of a growth chamber prototype

Growth chambers for the study of effects of temperature, air humidity and CO₂-concentration on plant growth, with or without supplementary artificial light, are described. Each chamber has a volume of 1080 1. The mean airflow at plant level is 0.22 m s^?1. The temperature is controlled within ± 0.5°C in the range from 10°C lower to 20°C higher than the ambient temperature at low solar radiation. In direct sunshine, the temperature may rise 1°C at floor level and the gradient from the floor to the upper part of the chamber may be about 2°C.The relative humidity is generally controlled within ± 4%, in the range from 50 to 95%.The CO₂-concentration is controlled within ± 5% of the desired value. The number of air changes in the chambers may be controlled from 0 to 20 h^?1.Tests revealed no significant difference between the chambers with respect to fresh weight production of lettuce, rose or chrysanthemum. There was, however, a significant effect from the position within the chambers.     

Consequences of ignoring variable and spatially autocorrelated detection probability in spatial capture-recapture

Landscape Ecology - Spatial capture-recapture (SCR) models are increasingly popular for analyzing wildlife monitoring data. SCR can account for spatial heterogeneity in detection that arises from...