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91.
Assessing village authenticity with satellite images: a method to identify intact cultural landscapes in Europe 总被引:1,自引:0,他引:1
The village with its characteristic zones of different land use from the center to the periphery is a basic unit of Europe's cultural landscapes. However, loss of the authentic pre-industrial village structure characterized by a fine-grained structure of arable land and wooded grasslands is a threat to both cultural heritage and biodiversity in many rural landscapes. Therefore, it is important that the extent and rate of change of such authentic villages in a landscape can be monitored. We studied to what extent loss of authenticity with increasing time after abandonment can be assessed by quantitative analysis and visual interpretation of satellite images. The study was carried out in the Bieszczady Mountains, SE Poland in 1999. Using Landsat Thematic Mapper data from 1998, both the grain size of landscape elements (size of fields) and land-cover composition (encroachment of shrub and forest) were quantitatively described 6 type villages representing different stages of deterioration of the authentic village structure. Historical maps were used to delineate the border of the villages and the former extension of forest and open land was measured. The present land use and the degree of abandonment expressed as grain size and forest encroachment were mapped using satellite data. Deterioration occurred along 2 transformation paths: abandonment and ultimately becoming forest, or intensified agriculture, respectively. To validate these results we classified 22 other villages in a 1000 km2 area by visual interpretation of the original satellite images into 1 of 4 types. We then collected historical data on human population changes over the past six decades. The classification of village authenticity was clearly related to the rate of human population decline. We address the importance of validating and applying this approach for rapid assessment of the authenticity of cultural landscapes in European regions being subject to ongoing as well as expected future change, related to expansion of the European Union. Finally, we argue that the village represents a scale at which integration of natural and social sciences is possible. 相似文献
92.
Sulphur deposition in Sweden has decreased to less than half of the levels recorded in 1970 and now signs of recovery from acidification of surface waters are beginning to appear. We investigated time trends of water chemistry between 1985 and 1998 in 13 streams draining small forested catchments with generally shallow acid sensitive soils. At nine of the catchments, bulk deposition was monitored as well. Sulphate concentrations decreased in both stream water and deposition, although with somewhat smaller trends in stream water compared with deposition. The magnitude of the trends in sulphate increased from north to south, following a gradient of increasing industrial influence. Five sites in the southern half of the country showed weak signs of recovery from acidification in terms of increasing concentrations of acid neutralising capacity and decreasing concentrations of hydrogen ions, corresponding to annual increases of 0.01 pH units. Changes in stream discharge and concentrations of marine salts and organic acids could not explain the observed decrease in acidity and the results were interpreted as recovery from anthropogenic acidification. For the northern half of Sweden, any changes in water chemistry could be attributed to natural variation in climate and marine influence, and the effect of anthropogenic acidification was negligible. 相似文献
93.
The Rossby Centre Regional Atmospheric Climate Model part II: application to the Arctic climate 总被引:1,自引:0,他引:1
The Rossby Centre regional climate model (RCA2) has been integrated over the Arctic Ocean as part of the international ARCMIP project. Results have been compared to observations derived from the SHEBA data set. The standard RCA2 model overpredicts cloud cover and downwelling longwave radiation, during the Arctic winter. This error was improved by introducing a new cloud parameterization, which significantly improves the annual cycle of cloud cover. Compensating biases between clear sky downwelling longwave radiation and longwave radiation emitted from cloud base were identified. Modifications have been introduced to the model radiation scheme that more accurately treat solar radiation interaction with ice crystals. This leads to a more realistic representation of cloud-solar radiation interaction. The clear sky portion of the model radiation code transmits too much solar radiation through the atmosphere, producing a positive bias at the top of the frequent boundary layer clouds. A realistic treatment of the temporally evolving albedo, of both sea-ice and snow, appears crucial for an accurate simulation of the net surface energy budget. Likewise, inclusion of a prognostic snow-surface temperature seems necessary, to accurately simulate near-surface thermodynamic processes in the Arctic. 相似文献
94.
Badge size in the house sparrow Passer domesticus 总被引:6,自引:0,他引:6
Anders Pape M//oller 《Behavioral ecology and sociobiology》1988,22(5):373-378
Summary I studied female mate choice in house sparrows Passer domesticus in relation to the size of the black throat patch of males (badge size), which is a signal of dominance status, and to territory quality. Males with large badges obtained a mate earlier in spring than males with small badges. Males which remained unmated during the entire breeding season had smaller badges than mated males, even when controlling for the effect of other morphological traits and age. Largebadged males had territories with more breeding sites than small-badged males. Territories defended by males with large badges primarily had hole nest sites, which were safe from predators, and nestlings rarely fell from hole nests. Females were implanted with estradiol to induce copulation solicitation displays. Females responded more strongly to a male taxidermic mount and song than to song alone, and they responded more strongly and frequently to male mounts with large badges. Female house sparrows chose mates on the basis of male badges and perhaps on the basis of the quality of the nesting territories offered. 相似文献
95.
Juan José Soler Manuel Soler Anders Pape Møller Juan Gabriel Martínez 《Behavioral ecology and sociobiology》1995,36(3):201-206
When brood parasites are about to lay an egg, they have to decide which nest to parasitize. The best nest in which to lay will depend on the parenting ability of the host. We have studied selection of magpie (Pica pica) hosts by great spotted cuckoos (Clamator glandarius). Great spotted cuckoos preferentially parasitize large host nests. Nest volume in magpies is a good indicator of territory quality, since there is a negative relationship between magpie nest size and breeding date, and timing of breeding in magpies is known to be positively related to territory quality. Moreover, magpies occupying high-quality territories have high breeding success. Therefore, nest size is positively related to the quality of magpies. Parasitized magpie nests were of greater volume than the nearest neighbouring nest not parasitized by the great spotted cuckoo. In order to test whether the great spotted cuckoos might select high-quality magpie hosts, we manipulated pairs of parasitized and non-parasitized nests with identical laying dates and habitats, introducing into each of the nests the same number of parasitic and non-parasitic eggs. The number of fledglings reared (magpie plus great spotted cuckoo chicks) in naturally parasitized nests was higher than in experimentally parasitized nests. Thus, the probability of survival of the parasite chicks increased if cuckoo eggs were laid in the nests of high-quality hosts originally chosen by the parasite. 相似文献
96.
Anders Pape Møller 《Behavioral ecology and sociobiology》1987,21(2):119-123
Summary The importance of mate guarding by males in the monogamous swallowHirundo rustica was studied by temporarily detaining the males. Mate guarding reduced the frequency of extra-pair copulations and of sexual
chases involving female mates. Males participated in sexual chases more frequently if they had a non-fertile female. Neighbouring
males of ‘widowed’ females increased their own mate guarding presumably in response to the experimentally increased rate of
sexual chases. Neighbouring males with a fertile female increased their mate guarding more than did males with a non-fertile
female.
Addition of eggs to swallow nests in the post-fledging period of the first brood induced mate guarding by male nest owners.
These males also copulated more frequently with their mates than did control males. Neighbouring male swallows responded to
the increased mate guarding by showing sexual interest in the guarded females.
removal of eggs from swallow nests during the laying period, leaving only one egg in the nest, resulted in reduced nest attendance
by females. Male mates responded by increasing their mate guarding intensity as compared to controls, and neighbouring males
showed an increased sexual interest in these females. 相似文献
97.
Anders Biel Ulf Dahlstrand Gunne Grankvist 《Ambio-人类环境杂志》2005,34(4):354-359
个人行为必须对环境有利,这是现代社会日益增长的需求.在这场变革中,旨在改变人们态度的信息宣传是它的必备前提.信息宣传虽然可能是必不可少的,但是它本身并不足以完成促进变革的任务.我们认为,首先,许多影响环境的日常行为,都是习惯成自然的行为.可是,几乎没有人关注这个特点,并通过信息导向来改变这些习惯行为.另外一些情况下,行为更主要是由价值导向的.不过,除了可能的环境后果之外,还有其它信息更可能吸引行为人的注意,影响其行为选择.为了研究消费者行为,我们进行了调查和实验,研究什么样的信息条件更容易影响对环境关注水平不同的人们.基于这些研究,讨论对行为改变的含义. 相似文献
98.
Ugochukwu E. Aronu Hallvard F. Svendsen Karl Anders Hoff 《International Journal of Greenhouse Gas Control》2010,4(5):771-775
The carbon dioxide capture potential of amine amino acid salts (AAAS), formed by mixing equinormal amounts of amino acids; e.g. glycine, β-alanine and sarcosine, with an organic base; 3-(methylamino)propylamine (MAPA), was assessed by comparison with monoethanolamine (MEA), and with amino acid salt (AAS) from amino acid neutralized with an inorganic base; potassium hydroxide (KOH). Carbon dioxide absorption and desorption experiments were carried out on the solvent systems at 40 °C and 80 °C respectively. Experimental results showed that amine amino acid salts have similar CO2 absorption properties to MEA of the same concentration. They also showed good signs of stability during the experiments. Amino acid salt from an inorganic base, KOH, showed lower performance in CO2 absorption than the amine amino acid salts (AAAS) mainly due to a lower equilibrium temperature sensitivity. AAAS showed better performance than MEA of same concentration. AAAS from neutralization of sarcosine with MAPA showed the best performance and the performance could be further enhanced when promoted with excess MAPA. The solvent comparison is semi-quantitative since the bubble structure, and thus gas–liquid interfacial area may not be the same for all experiments, however superficial gas velocities were kept constant. 相似文献
99.
Charlotta Pers Lars Rahm Anders Jonsson Ann-Kristin Bergström Mats Jansson 《Environmental Modeling and Assessment》2001,6(3):159-172
The organic carbon balance of a lake with high input of allochthonous organic carbon is modelled integrating physical, chemical and biological processes. The physical model captures the behaviour of real thermal stratification in the lake for different flow situations during the period 1993–1997. The dissolved organic carbon model is based on simulated trajectories of water parcels. By tracking parcels, account is kept of environmental factors such as temperature and radiation as well as DOC quality for each parcel. The DOC concentration shows seasonal variations primarily dependent on inflow. The organic matter degradation (bacterial- and photodegradation) in the lake amounts to 1.5–2.5 mg C l–1 yr–1, where photooxidation is responsible for approximately 10%. The estimated DIC production in the lake is large compared to sediment mineralisation and primary production. The main conclusion is that the model with the selected parameterisations of the degradation processes reasonably well describes the DOC dynamics in a forest lake. 相似文献
100.
Erik Jerndal Tobias Mattisson Ivo Thijs Frans Snijkers Anders Lyngfelt 《International Journal of Greenhouse Gas Control》2010,4(1):23-35
Chemical-looping combustion is a novel combustion technology with inherent separation of the greenhouse gas CO2. The technology uses circulating oxygen carriers to transfer oxygen from the combustion air to the fuel. In this paper, oxygen carriers based on commercially available NiO and α-Al2O3 were prepared using the industrial spray-drying method, and compared with particles prepared by freeze-granulation. The materials were investigated under alternating oxidizing and reducing conditions in a laboratory fluidized bed, thus simulating the cyclic conditions of a chemical-looping combustion system. The particles produced by spray-drying displayed a remarkable similarity to the freeze-granulated oxygen carriers, with high reactivity when the bed was fluidized and similar physical properties when sintered at the same temperature. This is an important result as it shows that the scaling-up from a laboratory production method, i.e. freeze-granulation, to a commercial method suitable for large-scale production, i.e. spray-drying, did not involve any unexpected difficulties. A difference noticed between the spray-dried and freeze-granulated particles was the sphericity. Whereas the freeze-granulated particles showed near perfect sphericity, a large portion of the spray-dried particles had hollow interiors. Defluidization was most likely to occur for highly reduced particles, at low gas velocities. The apparent density and crushing strength of the oxygen carriers could be increased either by increasing the sintering temperature or by increasing the sintering time. However, the fuel conversion was fairly unchanged when the sintering temperature was increased but was clearly improved when the sintering time was increased. 相似文献