Urban Intensity Research Articles

城市化对河流大型底栖动物群落的影响研究进展

PDF HTML阅读 XML下载 导出引用 引用提醒 城市化对河流大型底栖动物群落的影响研究进展 DOI: 10.5846/stxb201606241242 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31500375）；中国博士后科学基金项目（2014M552296）；国家科技重大专项（2013ZX07104-004-05）；西南大学科研基金项目（SWU112049） Advances in research on the influence of urbanization on stream benthic macroinvertebrate communities Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:城市化可以引发一系列"城市溪流综合症"，对河流健康造成巨大胁迫。大型底栖动物是河流生态系统的重要组成部分，对环境因子敏感，能够较好的反映流域环境的变化。城市化后，流域人口增加，建设用地比例上升，入河污染物浓度和总量增多，底栖动物中敏感物种比例降低甚至消失，寡毛类、摇蚊等耐污物种成为优势类群；群落多样性显著降低，并且一般与城市化强度成负指数关系；底栖动物总密度普遍大幅度增加，收集者为主要摄食功能群；不透水地表面积比例的增加改变了流域自然的水文过程，群落组成的季节波动减弱，但密度的波动增大；次级生产力明显增加，食物网趋于简化。初步分析了城市化过程中水质污染、水文、生境破坏、流域土地利用等因素影响底栖动物群落的规律和机制，并且根据国内外研究现状提出了进一步研究的方向，以期为我国城市河流生态学研究、流域生态管控和河流生态系统修复提供科学依据。 Abstract:Urbanization imposes considerable stress on river health and leads to the so-called "Urban Stream Syndrome." As an important components in running water ecosystems, benthic macroinvertebrate is sensitive to environmental change and can reflect variations in watershed environments. As a consequence of rising of populations and percentage of construction area associated with increasing urbanization, there have been marked increases in the total amount and concentration of pollution discharged into rivers. As a result, populations of sensitive species either disappear or are reduced in size, whereas Oligochaeta and Chironomidae become the dominant taxa. Biodiversity is decreased and shows a negative and exponential relationship with the intensity of urbanization. Total density of stream biota increases significantly, and collectors become the dominant functional feeding group. The increase in impervious area changes the hydrologic processes of watersheds. Seasonal dynamics of the community component is decreased, whereas the variation in density is increased. Secondary productivity increases, and food web is reduced in complexity. The present paper summarizes the principles and mechanisms underlying the effects of water pollution, hydrology, stream habitat, and land use on stream macroinvertebrates. Further research on urban stream macroinvertebrate ecology is also proposed. It is hoped that this review will promote urban stream ecology research and provide a scientific basis for watershed ecological management and river restoration. 参考文献 相似文献 引证文献

Illusions in Stone dir. by Brian Brazeal

Reviewed by: Illusions in Stone dir. by Brian Brazeal Les W. Field Brian Brazeal, dir. Illusions in Stone. Produced by the Advanced Laboratory for Visual Anthropology. California State University, Chico. Chico: ALVA Productions, 2016. 58 min. www.csuchico.edu/alva/projects/2016/illusions-in-stone.shtml There are no doubt people—and some of them, anthropologists—for whom gems exercise neither overt fascination nor covert desire, neither scholarly intent nor aesthetic stimulation, neither revulsion at the barbarities associated with their mining nor disgust with the excesses of the affluent who alone can afford the best specimens. I admit I am not one of those people, and in fact all of the aforementioned reactions, discrete yet mixed up like the thick Colombian stew ajiaco, are part of how I think about gems. Brian Brazeal is also a scholar for whom gems provoke this complex mixture of contradictory emotions and honed research interests. As the director and producer of this superb film, he aims those many points of inquiry at a stone whose character is among the most profoundly and simultaneously attractive and revolting—the emerald. The 58-minute film follows the contours of the model of multi-sited ethnography described and advocated by George Marcus's "Ethnography in/of the World System: The Emergence of Multi-sited Ethnography" (1995). Brazeal's footage moves (in order) from Brazil to India, from there to Zambia, and then on to Tel Aviv and New York City. The last third of the film takes place in Bogotá and Boyacá province, Colombia, where the finest stones in the world are mined and have been mined both before and since the Spanish conquest of the 16th century. The film's title, "Illusions in Stone," as a running theme, reprises repeatedly. "Illusion" evokes the representational world in which humans [End Page 1251] live, populated by complex interactions between language, symbol, and multi-dimensional cultural constructions. In this film, the illusions revolve primarily around the lived meanings of the cultural construction of wealth, as that concept is experienced very differently by the interlocutors of a highly stratified and unequal global production and trading system. As the film's optic moves from site to site, the different levels of illusion are narrated by Brazeal's interlocutors and shown in visually striking and beautiful cinematographic scripting. The alternating lush and barren landscapes, rural isolation and urban intensity are matched by a remarkable soundtrack that includes sacred Jain music, Colombian vallenatos, and new Zambian beats. This is a beautifully crafted film characterized by high production quality all around. For gems in general, and emeralds quite specifically, the illusion is all about wealth. The impoverished miners in Brazil, Zambia, and Colombia go back to the grinding, dangerous, degrading, and hopeless work of mining every day under the illusion that they might, against all odds, strike it rich with a fabulous stone, or better yet a rich vein of stones. The illusion is sustained by repeated statements made by individuals in all three countries about the metaphysical characteristics of both gems and the search for them. Greed, as both miners and gem traders assert, sabotages the possibility of getting lucky. The miners, in particular, declaim that the stones possess their own fate as sentient beings, and that, moreover, it is faith in God that makes it possible for miners to intersect with the fate of a particular emerald. These statements are treated as credulous, yet are declared adjacent to the ongoing theme of illusion. Brazeal does not editorialize, but allows his interlocutors to elaborate on such apparent contradictions—illusion and faith, suffering of people, and sentience of stones—as veins of life as complexly unique as the emeralds themselves. Indeed, the unique qualities of each emerald and the impossibility of objective assessment across stones is another ongoing narrative stated as fact in all six countries. For the buyer of the rough stone, the person who will cut and facet the stone, the illusion is sustained by the vast difference between what they pay the miner and how much they can potentially sell a stone for, provided someone sees great beauty and possibility in it. A cutter-polisher will pay a good price if s...

Influence of urbanization on the occurrence and activity of aerial insectivorous bats

Activity and species-specific responses of insectivorous bats in different urban-forest conditions provides a general perspective on the adaptability and vulnerability of bat species towards urbanization intensity. Here we evaluated species richness and activity patterns of aerial insectivorous bats across an urbanized landscape in the highlands of Chiapas, in Mexico. Acoustic monitoring of echolocation calls was conducted for 27 nights over a period of four months. Species richness and relative activity of insectivorous bats were estimated in a landscape with different conditions of urbanization intensity: urban areas, non-urban and forest areas. We identified a total of 14 bat species and three phonotypes. Bat species richness and relative activity was similar (X2 = 0.568, gl = 2, p > 0.05), but species composition differed among conditions. We observed a significant higher occurrence of Bauerus dubiaquercus, Eptesicus brasiliensis and Myotis californicus in forest sites. Urban sites presented higher occurrence of Molossus rufus and phonotype Molossidae 2, while non-urban sites presented a higher occurrence of Eptesicus furinalis and phonotype Molossidae 2. We were able to identify bat species according to their relative activity in relation todifferent landscape conditions. Species of the Molossidae family presented the highest activity in urban sites, which was positively affected by the number of streetlights, while species of the Vespertilionidae presented the highest activity in forest sites, which was positively related totree density. While urbanization tends to diminish native biodiversity and alter faunal communities, our results show a similar richness and relative activity of aerial insectivorous bats along the urban ecosystem. The effect of urbanization intensity becomes more apparent in species-specific bat activity; the response of species towards particular habitat conditions depends on local habitat quality and characteristics (i.e., presence of streetlights, vegetation cover and tree density).

Risk of encountering ticks and tick-borne pathogens in a rapidly growing metropolitan area in the U.S. Great Plains

The prevalence of tick-borne diseases has increased dramatically in many urban areas of the U.S., yet little is known about the ecology of ticks and tick-borne pathogens in relation to characteristics of North American urban and suburban landscapes. This study aimed to begin identification of the risk of encountering ticks and tick-borne pathogens within a rapidly expanding metropolitan area in the U.S. Great Plains region. Ten sites across Oklahoma City, Oklahoma were selected for tick sampling based on presence of tick habitat and level of urbanization intensity. Sampling was conducted using CO2 traps and flagging in June, July and October 2015. A total of 552 ticks were collected from eight of the ten sampled greenspaces. The majority of ticks collected in summer were Amblyomma americanum (N=534 (97.8%)), followed by Dermacentor variabilis (N=10 (1.8%)) and Amblyomma maculatum (N=2 (0.3%)). Ixodes scapularis adult females (N=4) and nymphal A. americanum (N=2) were also collected in October 2015. Tick species diversity was highest in sites with >15% of the surrounding landscape composed of undeveloped land. Rickettsia sp. (including R. amblyommii and ‘Candidatus R. andeanae’), Ehrlichia chaffeensis and/or E. ewingii were detected in tick pools from all eight sites where ticks were found. Our data suggest that the risk of encountering ticks and tick-borne pathogens exists throughout the Oklahoma City metropolitan area and that tick populations are likely influenced by urbanization intensity. Continued research is needed to clarify the full range of abiotic and biotic features of urban landscapes that influence the risk of encountering ticks and transmitting tick-borne diseases.

Obsolete Pesticide Contamination:A New Type of Water and Soil Pollution

The scale, intensity and rate of urbanization across the globe has caused significant environmental pollution and posed severe pressure on the natural resources. In Sudan, various human land-use processes have affected the natural ecosystem, especially pollution of soil and water. Pesticide contamination of soil and water has become a subject of nationwide importance because groundwater is used for drinking purposes by about 50% of the population in Sudan. This especially relates to the population inhabiting the agricultural areas where pesticides are most often used.

Impacts of urbanisation level and distance from potential natural mosquito breeding habitats on the abundance of canine dirofilariosis.

Dirofilariosis is an emerging mosquito-borne veterinary and medical problem in the Northern hemisphere. The ecological investigation of 56 canine dirofilariosis cases in new endemic locations was performed in Szeged, Hungary. The aim was to analyse the influence of the spatial patterns of dog abundance and the potential mosquito breeding habitats on the spatial occurrence patterns of dirofilariosis in the city of Szeged. The limnoecological characterisation was based on the fluvial habitat classification of Amoros of natural water bodies; the built environment was evaluated using the UrbanisationScore urbanisation intensity measuring software. Dirofilaria immitis accounted for 51% and D. repens for 34.3% of the dirofilariosis cases, and in 20% of the cases only the Knott's test was positive. It was concluded that most of the cases were related to locations with a medium to high urbanisation index, although the proximity of mosquito-bearing waters also played an important role in the observed spatial infection patterns. We found that the distance from potential mosquito habitats and the urbanisation intensity determine the abundance of dirofilariosis in urban environments.

Using trail cameras to estimate free‐ranging domestic cat abundance in urban areas

The domestic cat Felis catus is one of the most ecologically harmful invasive species on earth. Predation by free‐ranging cats poses a serious global threat to small vertebrates and is a leading source of anthropogenic mortality for birds and small mammals in North America. However, little is known about the size of cat populations, especially in urban areas where both cats and wildlife are abundant. Methods to quantify free‐ranging cat populations are needed to understand the magnitude of threats facing wildlife populations and to inform decisions about prioritizing conservation and cat population management. We assessed the utility of trail cameras and sight—resight analysis for estimating free‐ranging cat abundance in a small urban area (Stillwater, OK, USA). We also evaluated whether relationships exist between cat abundance and both urban development intensity and human population density. Even with relatively large cat populations, we identified the vast majority (∼96.5%) of individual cats in both day‐time and night‐time photos. We found no relationship between cat abundance and either urban development intensity or human population density. This finding combined with the large numbers of cats observed suggests that cats may be abundant in our study area regardless of urban context. Sampling freeranging cat populations across a broad range of urbanization intensities that capture a variety of human behaviors and/or cat management policies is needed to shed light on the drivers of cat population abundance. Trail cameras show promise as a highly useful tool for achieving this objective in the context of wildlife conservation management.

Interspecific variation in the relationship between clutch size, laying date and intensity of urbanization in four species of hole-nesting birds.

The increase in size of human populations in urban and agricultural areas has resulted in considerable habitat conversion globally. Such anthropogenic areas have specific environmental characteristics, which influence the physiology, life history, and population dynamics of plants and animals. For example, the date of bud burst is advanced in urban compared to nearby natural areas. In some birds, breeding success is determined by synchrony between timing of breeding and peak food abundance. Pertinently, caterpillars are an important food source for the nestlings of many bird species, and their abundance is influenced by environmental factors such as temperature and date of bud burst. Higher temperatures and advanced date of bud burst in urban areas could advance peak caterpillar abundance and thus affect breeding phenology of birds. In order to test whether laying date advance and clutch sizes decrease with the intensity of urbanization, we analyzed the timing of breeding and clutch size in relation to intensity of urbanization as a measure of human impact in 199 nest box plots across Europe, North Africa, and the Middle East (i.e., the Western Palearctic) for four species of hole‐nesters: blue tits (Cyanistes caeruleus), great tits (Parus major), collared flycatchers (Ficedula albicollis), and pied flycatchers (Ficedula hypoleuca). Meanwhile, we estimated the intensity of urbanization as the density of buildings surrounding study plots measured on orthophotographs. For the four study species, the intensity of urbanization was not correlated with laying date. Clutch size in blue and great tits does not seem affected by the intensity of urbanization, while in collared and pied flycatchers it decreased with increasing intensity of urbanization. This is the first large‐scale study showing a species‐specific major correlation between intensity of urbanization and the ecology of breeding. The underlying mechanisms for the relationships between life history and urbanization remain to be determined. We propose that effects of food abundance or quality, temperature, noise, pollution, or disturbance by humans may on their own or in combination affect laying date and/or clutch size.

Butterflies in the city: a review of urban diurnal Lepidoptera

Human migration to urban centers has resulted in diverse environmental disturbances that affect biodiversity. Although urbanization has been highlighted as one of the main drivers of biodiversity endangerment, this topic is still poorly studied in many countries. In order to establish the status quo of the ecology of butterflies in urban centers, we gathered publications focused on urban butterflies (Lepidoptera). We compiled a total of 173 studies from 37 countries and more than 110 urban areas, including published papers and theses (1956–2015). Most papers (69 %) addressed ecological topics, 14 % were focused on biological conservation, and 17 % corresponded to species lists. In summary, most studies revealed a negative impact of urbanization intensity on butterfly diversity (richness and abundance). In fact, we found studies reporting local extinctions due to urbanization, highlighting the causes related to them. The study of charismatic urban wildlife groups, such as butterflies, is a promising field, as there are still important gaps in our comprehension of the ecological patterns and processes that occur in urban areas. Undoubtedly, understanding the response of butterflies to urbanization will aid in the development of urban biodiversity management, planning, and conservation strategies worldwide, which together with knowledge of other wildlife groups and socioeconomic variables, will lead us to more sustainable, livable, and biodiverse cities.

URBAN MORPHOLOGICAL DYNAMICS IN SANTIAGO (CHILE): PROPOSING SUSTAINABLE INDICATORS FROM REMOTE SENSING

Latin America is one of the world’s most urbanised regions, with more than 80% of inhabitants living in urban areas and over 50 cities with at least 1 million inhabitants. The concept of urban structure types (UST) allows the dynamics of a growing urban environment to be captured in its quantity and quality. They are defined as areas of homogenous appearance in the urban matrix with a recognisable mixture of built-up areas and open spaces. We used the vegetation-impervious-soil (V-I-S) model approach to classify and monitor different types of USTs in Santiago (~800 km2), Chile between 1985 and 2015. The V-I-S model is based on a simplification of the large diversity of urban land cover types in three general categories: vegetation, impervious surfaces and soil. These categories were obtained by processing Landsat-5 TM and Landsat-8 OLI images. First, we applied standard radiometric calibration and co-registration methods to all datasets. Second, using a linear spectral unmixing algorithm we performed a soft classification of urban land cover types (<i>end members</i>): trees, shrubs, herbaceous plants, soils, buildings, roads and water bodies. All <i>end members</i> were validated using a combination of photointerpretation on high-resolution images (~1 m) and field data collection (only for 2015). In each pixel we used the resulting probability scores, logically grouped, to obtain final values for each V-I-S component. Third, we used statistical clustering of V-I-S values to create a set of eight pixel groups, which we interpreted as USTs and mapped them for each date. The overall accuracy for V-I-S components in 1985 and 2015 were 78% and 82%, respectively, and errors did not exhibit any spatial correlation. The main sources of differentiation between USTs were the trade-off proportions between vegetation and impervious components, whereas soil proportions remained near 5% across the city in both dates. To analyse the change in UST spatial configuration between dates, we used a set of selected landscape metrics and discussed their use as indicators for sustainable urban development. These indicators relate to the dispersion pattern of urban growth, the connectivity of open green space and the complexity in the composition of the UST types within the different sectors of the city. We were able to identify, using the dynamics exhibited by the USTs, three main zones: (1) city centre, where USTs of high-intensity development predominate, (2) eastern high-income areas whose spatial structure is marked by a relatively high urbanisation intensity with a very large proportion of vegetated spaces, and (3) peripheral areas, with significant changes in composition and configuration of USTs, in recent decades, showing high rates of urbanisation, shifting from low-medium to high densities. We concluded that these patterns and their dynamics are mainly determined by the spatial socio-economic stratification of the population.

URBAN MORPHOLOGICAL DYNAMICS IN SANTIAGO (CHILE): PROPOSING SUSTAINABLE INDICATORS FROM REMOTE SENSING

Abstract. Latin America is one of the world’s most urbanised regions, with more than 80% of inhabitants living in urban areas and over 50 cities with at least 1 million inhabitants. The concept of urban structure types (UST) allows the dynamics of a growing urban environment to be captured in its quantity and quality. They are defined as areas of homogenous appearance in the urban matrix with a recognisable mixture of built-up areas and open spaces. We used the vegetation-impervious-soil (V-I-S) model approach to classify and monitor different types of USTs in Santiago (~800 km2), Chile between 1985 and 2015. The V-I-S model is based on a simplification of the large diversity of urban land cover types in three general categories: vegetation, impervious surfaces and soil. These categories were obtained by processing Landsat-5 TM and Landsat-8 OLI images. First, we applied standard radiometric calibration and co-registration methods to all datasets. Second, using a linear spectral unmixing algorithm we performed a soft classification of urban land cover types (end members): trees, shrubs, herbaceous plants, soils, buildings, roads and water bodies. All end members were validated using a combination of photointerpretation on high-resolution images (~1 m) and field data collection (only for 2015). In each pixel we used the resulting probability scores, logically grouped, to obtain final values for each V-I-S component. Third, we used statistical clustering of V-I-S values to create a set of eight pixel groups, which we interpreted as USTs and mapped them for each date. The overall accuracy for V-I-S components in 1985 and 2015 were 78% and 82%, respectively, and errors did not exhibit any spatial correlation. The main sources of differentiation between USTs were the trade-off proportions between vegetation and impervious components, whereas soil proportions remained near 5% across the city in both dates. To analyse the change in UST spatial configuration between dates, we used a set of selected landscape metrics and discussed their use as indicators for sustainable urban development. These indicators relate to the dispersion pattern of urban growth, the connectivity of open green space and the complexity in the composition of the UST types within the different sectors of the city. We were able to identify, using the dynamics exhibited by the USTs, three main zones: (1) city centre, where USTs of high-intensity development predominate, (2) eastern high-income areas whose spatial structure is marked by a relatively high urbanisation intensity with a very large proportion of vegetated spaces, and (3) peripheral areas, with significant changes in composition and configuration of USTs, in recent decades, showing high rates of urbanisation, shifting from low-medium to high densities. We concluded that these patterns and their dynamics are mainly determined by the spatial socio-economic stratification of the population.

Prevalent vegetation growth enhancement in urban environment

Urbanization, a dominant global demographic trend, leads to various changes in environments (e.g., atmospheric CO2 increase, urban heat island). Cities experience global change decades ahead of other systems so that they are natural laboratories for studying responses of other nonurban biological ecosystems to future global change. However, the impacts of urbanization on vegetation growth are not well understood. Here, we developed a general conceptual framework for quantifying the impacts of urbanization on vegetation growth and applied it in 32 Chinese cities. Results indicated that vegetation growth, as surrogated by satellite-observed vegetation index, decreased along urban intensity across all cities. At the same time, vegetation growth was enhanced at 85% of the places along the intensity gradient, and the relative enhancement increased with urban intensity. This growth enhancement offset about 40% of direct loss of vegetation productivity caused by replacing productive vegetated surfaces with nonproductive impervious surfaces. In light of current and previous field studies, we conclude that vegetation growth enhancement is prevalent in urban settings. Urban environments do provide ideal natural laboratories to observe biological responses to environmental changes that are difficult to mimic in manipulative experiments. However, one should be careful in extrapolating the finding to nonurban environments because urban vegetation is usually intensively managed, and attribution of the responses to diverse driving forces will be challenging but must be pursued.

Wetland Transitions and Protection under Rapid Urban Expansion: A Case Study of Pearl River Estuary, China

Understanding wetland changes under urbanization is important for wetland management. In this study, net transition intensity (NTI) and total transition intensity (TTI) are presented to characterize wetland transitions based on spatial data obtained from Landsat satellite images of Pearl River estuary in South China. NTI is commonly used to represent changes in absolute amounts for each class of wetland, while TTI reflects the internal transition activities and amounts. The third index, the urbanization intensity index (UII), is used to investigate the intensity and velocity of urban land expansion at the same time periods. The results show that one-third of the total wetland area was lost from 1979 to 2009 in the study area and seven types of estuarine wetlands were degraded. The basic pattern of wetland transition is from natural wetlands to constructed wetlands and then to urban lands. Intertidal mud and sand and paddy fields were the major natural and constructed wetlands, respectively, transferred to urban lands. The TTI value was generally greater than the NTI value for these wetlands. TTI >> NTI is an important indicator for wetland transitions under rapid urban expansion in the Pearl River estuary. Based on the integration of the two indices (NTI and TTI), a protection and management plan framework for the Pearl River estuary wetlands is proposed. This plan emphasizes the key and important zones and their different features, and includes actions that can be implemented in and around natural and constructed wetlands.

Research on the Relationship between Urban Development Intensity and Eco-Environmental Stresses in Bohai Rim Coastal Area, China

To realize sustainable urban development that minimizes environmental impacts, the relationship between urban development intensity and eco-environmental stresses should be clearly revealed. This paper focused on the Bohai Rim coastal area, where cities have experienced significant development in the last decade. An index system was developed to quantify the comprehensive urban development intensity (CDI) and comprehensive eco-environment stresses (CES). Remote sensing imagery and statistical data were used to provide indices for CDI and CES. Spatiotemporal analysis was carried out on the correlation between the two indices. The coupling between the CDI and CES was then investigated to explore the urban development characteristics of each city in the study area, its development level, and the trend of urban development. Results showed that human activities surrounding urban development were partly dependent on the use of ecological resources to a certain degree, and that the degree of dependence increased with year. To promote a sustainable level of urban development, the government should focus on not only the high development intensity, but also the high quality of the eco-environment. Dalian was a good model of how to achieve a balance between the two.

The concept of urban intensity and China's townization policy: Cases from Zhejiang Province

Urban intensity, in this paper, is measured by four related concepts: compactness, diversity, density, and connectivity. Together they lead to a single idea when considering spatial distributions potentially in a virtuous manner with regard to resource consumption, economic opportunity, social integration and environmental performance. The methodologies applied here included Moran's I, Shannon's index entropy, and accessibility isotimelines, which were then applied to real case scenarios in 20 towns in Zhejiang Province, selected based on their economic performances, population sizes, and geographical locations. Further inspection discovered that density, an outcome of urban form, is highly correlated to compactness, leading to its elimination. The results showed that among the varying spatial arrangements of urban activities, building footprints and infrastructural elements characterized by monocentric centers of use inscribed with well-defined and relatively uniform grids of streets and related networks, alongside of relatively integrated zones of use, seemed to perform best with regard to urban intensity. At the other end of the morphological spectrum, towns with sharp separations of uses and zones of development, often resulting in overall bifurcation of a town's spatial layout, performed less well. Also, linear forms for small towns were less favorable.

Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation

Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term.

Effects of urban land-use on largescale stonerollers in the Mobile River Basin, Birmingham, AL.

During the spring and fall of 2001 and the spring of 2002 a study was conducted to evaluate the health of the largescale stoneroller (Campostoma oligolepis) populations in streams along an urban land-use gradient. Sites were selected from a pool of naturally similar sub-basins (eco-region, basin size, and geology) of the Mobile River basin (MRB), using an index of urban intensity derived from infrastructure, socioeconomic, and land-use data. This urban land-use gradient (ULUG) is a multimetric indicator of urban intensity, ranging from 0 (background) to 100 (intense urbanization). Campostoma sp. have been used previously as indicators of stream health and are common species found in all sites within the MRB. Endpoints used to determine the effects of urban land-use on the largescale stoneroller included total glutathione, histology, hepatic apoptosis, condition factor and external lesions. Liver glutathione levels were positively associated with increasing urban land-use (r(2) = 0.94). Histopathological examination determined that some abnormalities and lesions were correlated with the ULUG and generally increased in prevalence or severity with increasing urbanization. Liver macrophage aggregates were positively correlated to the ULUG. The occurrence of nucleosomal ladders (indicating apoptotic cell death) did not correspond with urban intensity in a linear fashion. Apoptosis, as well as prevalence and severity of a myxozoan parasite, appeared to have a hormetic dose-response relationship. The majority of the biomarkers suggested fish health was compromised in areas where the ULUG ≥ 36.

Measuring the non-measurable: On mapping subjectivities in urban research

This essay offers for discussion two contentious issues: the need for non-reductive approaches to investigations of the urban and the need for explicit inclusion of subjectivities and sensuality in urban research. It presents fragments of a major international research project into urban intensity, Measuring the non-Measurable (Mn'M), which was conducted at Keio University, Tokyo. It is polemological as, in de Certeau's tradition, it hopes to help “force theory to recognise its own limits.” The main emphasis of issues of subjectivity and sensuality are found in: (1) our efforts to define urban intensity/quality, (2) various techniques to find and identify such qualities, and (3) ways of capturing, (re)presenting and sharing those subtle urban energies which escape easy, if any, definition. Capturing and representing the urban is viewed here as the task of mapping – of a non-traditional kind. A discussion about mapping subjectivities and sensualities constitutes the main body of the paper. The first part outlines key aspects of the theoretical background, then presents concrete examples constituting fragments from a number of dérive sessions conducted in Tokyo, Hong Kong, Bangkok and Singapore. The pattern of the second part of the essay changes in order to present prospects for further research and different practices opened up by those dérive sessions, or drifts. The style in the second part of this article abandons standard journal formatting in order to enable concepts to flow and cascade, drift and stutter. A text about mapping takes the form of a map. Such writing-as-mapping aims to stimulate readings other than those intended by the author. It asks questions and hints at the answers. What is a map? Why map? How to map? How to map what is difficult to even define? Or, indirectly, might maps capture qualities such as the earthiness of terra, or the sensuality of the human?

Urban predation: a case study assessing artificial nest survival in a neotropical city

Nest predation is an important ecological driver that can mold avian communities. Previous studies performed in urban areas support both predatory relaxation and increases when assessing natural and artificial nest predation. In this study, we assessed artificial nest predation pressure in a neotropical city considering spatial and habitat traits. Our results show that artificial nest predation was driven by the interaction between location and urbanization intensity, with visual predators being responsible for most predation. This supports the notion that urban areas can act as landscape entities that filter biodiversity. Our study, showing both predation relaxation and intensification in the same urban system, suggests that nest predation dynamics can be diverse throughout urban areas. Thus, the predation paradox can occur in parallel with scenarios in which rises in predator numbers can actually decrease nest survivorship. Future studies investigating nest predation in urban areas should take into account the spatial environmental heterogeneity of their system in order to fully capture the patterns and biases related to nest predation.

Tradition of Green Architecture in Lithuania. Is it Possible to Continue it?

Lithuanian tradition of green architecture – it is not only a perception of landscape identity, but also a perception of human-nature coexistence. Problems of ECO architecture are analyzed through narrower green architecture concept, as a field of cultural human activity, historical tradition of space. It is not only work field of urban planners, architects or landscape architects. It is a tradition of spontaneous relationship with the natural environment of every nation. Circle of investigated questions is urban expression of green architecture in Lithuanian cities. Two branches with different genesis roots are defined: from urban agriculture to city landscape . All possible development configurations of green architecture in future city should be associated with concept of self-sufficient city , that is to say, planned, regulated, balanced change, ensuring not only renewal of artificial structures but also renewal of natural structures. The subject is urgent because mistakes in this process only lead to collapse of the cities and destruction of nature. Lithuanian cities development : peculiarities and changes are inseparable from human effort to communicate with flora: practical use (food preparation), beautification of personal everyday life. In Lithuanian cities, manors and monasteries architects planned unique ensembles of green architecture . Urban planner of 20 th century included surrounding valuable natural landscape elements into urban fabric, they created systemic ‘Green structures of the city’. Emphasizing that Lithuanian cities identity is related to preserved structures of urban agriculture and green architecture (always vibrant and changing), thus formed objectives are to recognize, preserve and develop these structures. Discussing global trends of green architecture , we see that main of them are associated with intense urban growth and need to adapt natural talents, primarily in the sense of energy and natural environment. It is understandable that Lithuanian cities will not stay in eternal stagnation, however, their development suppose to immediately balance between two objectives: cities urban intensity should grow parallelly to intensity of green structures; proposals of cities development, their forms and objectives should be presupposed on political, juristical and educational basis – this is obligation of raising public ecological consciousness. DOI: http://dx.doi.org/10.5755/j01.sace.13.4.13609