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1.
Many species are threatened with extinction and efforts are underway worldwide to restore imperilled species to their native ranges. Restoration requires knowledge of species' historical diversity and distribution. For some species, many populations were extirpated or individuals moved beyond their native range before native diversity and distribution were documented, resulting in a lack of accurate information for establishing restoration goals. Moreover, traditional taxonomic assessments often failed to accurately capture phylogenetic diversity. We illustrate a general approach for estimating regional native diversity and distribution for cutthroat trout in the Southern Rocky Mountains. We assembled a large archive of historical records documenting human‐mediated change in the distribution of cutthroat trout (Oncorhynchus clarkii) and combined these data with phylogenetic analysis of 19th century samples from museums collected prior to trout stocking activities and contemporary DNA samples. Our study of the trout in the Southern Rocky Mountains uncovered six divergent lineages, two of which went extinct, probably in the early 20th century. A third lineage, previously declared extinct, was discovered surviving in a single stream outside of its native range. Comparison of the historical and modern distributions with stocking records revealed that the current distribution of trout largely reflects intensive stocking early in the late 19th and early 20th century from two phylogenetically and geographically distinct sources. Our documentation of recent extinctions, undescribed lineages, errors in taxonomy and dramatic range changes induced by human movement of fish underscores the importance of the historical record when developing and implementing conservation plans for threatened and endangered species.  相似文献   

2.
《Collegium antropologicum》1999,23(2):379-396
Human societies have inhabited parts of the Central European country of Austria for thousands of years. The development process shopping the landscape by this long period of human impact remains poorly understood. The present study is an attempt to research landscape history on a local scale and compares an alpine, pre-alpine and midland-village area in Austria. We have developed an appropriate concept to describe the landscape ecology features of the study areas in several stages of the past from 1733 on. The landscape analysis is based on the interpretation of different kinds of historical data (e.g., documents, maps) going back to the pre-industrial epoch, which has--at least in terms of landscape ecology--hardly been accessible until now. An important aim of the study is to localize the historical information in the landscape. Individual plots can be traced back even to the early 14th century. Based on the quality of the available historical data, the historical landscape is analysed with regard to categories such as form and intensity of land use, distribution of nutrients and water as well as the pattern of landscape elements and their ecological functions. The comparison of present stages with former ones yields detailed knowledge on the dynamics and stability of landscape structure. This approach allows present-day land units to be identified as a result of long-term development going back to Medieval times. The primary aim of the study is to analyze factors that bring about change or resist it by creating stability. We therefore examine factors coupling landscape structure, agricultural production and population development. For this reason, we have studied the people and the evidence for their labor over a period of 400 years (1400-1800). Besides demographic data of the 18th and 19th century, historical registrar material has been collected; it enabled the land tenures to be reconstructed from the 15th to the 19th century. This type of data is a valuable source of information for investigating the socio-economic status of a local population or its farmsteads. The collected data reveal similarities in trends between time series of demography, land holding stability and landscape ecology features. A theoretical model shows how population, production and natural resources are connected in the investigated pre-modern communities.  相似文献   

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4.
Longstanding demographic growth accompanied by rising settlement activities and development of industry led to an increasing demand on utilization of wood. Tree species were selected for their specific properties. As a consequence of regional differences of forest species composition, wood has become an extremely important trade commodity. Therefore, the utilization of individual species could substantially change in space and time. In this study, we use 8´135 precisely dated timber constructions from a dendrochronological database to investigate spatio-temporal changes in wood utilization across the Czech lands from the 15th to the 19th century. Our results suggest that the utilization of individual species in historical timber constructions was primarily limited by their availability. Species selection was also based on wood properties and stem geometry. Most of historical constructions (99.7%), represented mainly by roofs and ceilings, are made of fir, spruce, pine, and oak. While fir constructions prevail in eastern Moravia and Silesia, spruce constructions are largely spread across the western and central part of the Czech Republic. Pine and oak constructions reflect natural occurrence of such forests in lower elevated central Bohemia and southern Moravia. Although fir prevailed in timber construction in the late-Medieval and post-Medieval times, planting of spruce monocultures resulted in its significantly increased utilization by the end of the 19th century. This study demonstrates the value of dendrochronological databases as an indicator of historical wood utilization.  相似文献   

5.
It is now generally accepted that chromosomes in the cell nucleus are organized in distinct domains, first called chromosome territories in 1909 by the great cytologist Theodor Boveri. Yet, even today chromosomes have remained enigmatic individuals, whose structures, arrangements and functions in cycling and post-mitotic cells still need to be explored in full detail. Whereas numerous recent reviews describe present evidence for a dynamic architecture of chromosome territories and discuss the potential significance within the functional compartmentalization of the nucleus, a comprehensive historical account of this important concept of nuclear organization was lacking so far. Here, we describe the early rise of chromosome territories within the context of the discovery of chromosomes and their fundamental role in heredity, covering a period from the 1870th to the early 20th century (part I, this volume). In part II (next volume) we review the abandonment of the chromosome territory concept during the 1950th to 1980th and the compelling evidence, which led to its resurrection during the 1970th to 1980th.  相似文献   

6.
Abstract

This bibliography covers the historical aspects of hematoxylin and its close relative brazilin from their origin in dyewoods to their recently understood chemical reactions and properties. Until the end of the 19th century, dyewoods such as logwood were among the most commercially important natural dyes and investigations over a long period of time led to an extensive literature. The ready oxidation of hematoxylin to hematein, which subsequently can be complexed with metal ions or undergo reactions with acid to give isohematein, has provided a wealth of work for the organic chemist. The elucidation of the structure and subsequent synthesis of hematoxylin has proved to be a major incentive to chemists to discover novel chemical reagents for many years.  相似文献   

7.
三百年前杭嘉湖地区农业生态系统的研究   总被引:4,自引:0,他引:4  
一、引言许多世纪以前,中国农民就在江河下游三角洲和几大湖区附近自然条件优越的湿地上建立了高产而稳定的有机农业生态系统。一些古代农学家曾对这些农业生态系统作过大量的研究。《补农书》(亦称《沈氏农书》)记述了明末清初时期长江下游杭嘉湖平原的农业生产技术和农村经济情况。本文试图根据《补农书》所提供的基本信息(张履祥,1658),并参照研究此农书的有关著作(陈恒力,1957;1958;陈恒力和王达,1983)和当时的地方志  相似文献   

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9.
Statural growth in human populations is a sensitive indicator of socio-economic well-being, and improvements in socio-economic status are reflected in secular increases in adult height. In the present study, we investigated the statures of historical Korean societies to show how stature changed over time. Applying Fujii's equation, derived from modern Japanese, to the measurement of femora removed from 15th- to 19th-century Joseon tombs, the average heights of Korean adults during the Joseon dynasty were estimated to be 161.1 ± 5.6 cm and 148.9 ± 4.6 cm for males and females, respectively. Plotting statures for successive historical societies against time revealed that Korean heights remained relatively unchanged through to the end of the 19th century, a pattern that differs from that seen in many Western countries in which stature transiently decreases after the Middle Ages. In contrast, a sharp increase in Korean stature was observed at the beginning of the 20th century, similar to trends seen in other nations (although exact timing varies in different countries). There were no accompanying changes of stature sexual dimorphism. The data reported in this study reflect the unique historical experience of Korea; the relative isolation of Joseon society, the late onset of modernization (at the end of the 19th century), and the later occurrence of industrialization (during the 1960s).  相似文献   

10.
Vegetation data in an early 20th century map from northern Tanzania are presented and discussed for its potential of expanding the analytical time-frame in studies of land-use and land-cover change. The starting point is that much research on land-use and land-cover change suffers from a time-frame bias, caused by limitations in remote sensing data. At the same time, the use of historical maps as a complementary data-set is rather insignificant. Can information in historical maps be used to extend the baseline in land-use and land-cover change studies? The historical context of the vegetation data is evaluated, and as an illustration of its potential for interdisciplinary research on land-cover and ecosystems change, a section of the map is juxtaposed with a recent pollen record specifically addressing the impact of a 'large infrequent disturbance' (LID) event at the end of the 19th century. It is concluded that the vegetation data in the map are not likely to be reflecting an extreme situation due to the LID event. Finally, the historical vegetation data were visually compared with a national 1995 land-cover data set, illustrating the possibility of using the map data as a baseline in land-cover change studies.  相似文献   

11.
许再富 《生物多样性》2000,8(1):112-119
根据有关历史资料的统计分析,在元朝以后,滇南各土司向天朝上贡的犀角估算有79~123支,并在清朝于18世纪末19世纪初犀牛就成为濒于灭绝的物种,而最后的一头犀牛是在1957年在滇南被捕杀。滇南各土司在元朝以后向天朝上贡的大象估算有1140~1339头、象牙38~76支,加上大象和犀牛被用于频繁的战争,它在17世纪中期就处于濒危的状态。因而,向天朝上贡这一特殊的人文因素是大象和犀牛在滇南濒危和灭绝的重要原因之一。虽然犀牛已在滇南灭绝,但从现代的生态环境来说,实现再引种是可能的。  相似文献   

12.
The understanding of fish communities' changes over the past centuries has important implications for conservation policy and marine resource management. However, reconstructing these changes is difficult because information on marine communities before the second half of the 20(th) century is, in most cases, anecdotal and merely qualitative. Therefore, historical qualitative records and modern quantitative data are not directly comparable, and their integration for long-term analyses is not straightforward. We developed a methodology that allows the coding of qualitative information provided by early naturalists into semi-quantitative information through an intercalibration with landing proportions. This approach allowed us to reconstruct and quantitatively analyze a 200-year-long time series of fish community structure indicators in the Northern Adriatic Sea (Mediterranean Sea). Our analysis provides evidence of long-term changes in fish community structure, including the decline of Chondrichthyes, large-sized and late-maturing species. This work highlights the importance of broadening the time-frame through which we look at marine ecosystem changes and provides a methodology to exploit, in a quantitative framework, historical qualitative sources. To the purpose, naturalists' eyewitness accounts proved to be useful for extending the analysis on fish community back in the past, well before the onset of field-based monitoring programs.  相似文献   

13.
The birth of a language is a historical process, which develops through almost six stages corresponding to six main properties (genetic distance, geographical isolation, adoption of a writing system, elaboration of a literary koine, national consciousness, official status), which are specific to Western civilization and limited to our concern, i.e. the languages in contemporary Europe. The two last properties are the most important and conclusive in achieving the full status of language in contrast with dialect, speech, idiom, vernacular and so on. Consequently, in this perspective the birth of a language can be stated when its use is felt as a token of national identity and its official status is recognized by politic power. The history of some interesting cases during the 20th century, such as Luxemburgish, Feroese and Macedonian will throw a light on the possible future scenario of the languages of the Former Yugoslavia. Other disputed, although not so dramatic cases, like Sardinian, Aranese, Moldavian and Ruthenian, are dealt with together with recurrent topics on minority languages. The conclusion is that, unlike the worldwide tendency, the number of languages will probably increase within the greater European Union in the course of the 21st century.  相似文献   

14.
This paper includes data from the 11th century to the present day on athlete’s heart and its most controversial trait, myocardial hypertrophy. Four historical stages in the evolution of the concept of athlete’s heart are considered: physical, electrocardiographic, echocardiographic, and magnetic resonance imaging stages.  相似文献   

15.
《American anthropologist》2009,111(4):517-518
ABSTRACT   This museum review places the American Anthropological Association's recent exhibition entitled "Race: Are We So Different?" into historical context by comparing it to other major exhibitions on race in the 20th century. I argue that although exhibitions on race in the 19th-century United States are frequently examined in the historical and anthropological literature, later exhibitions from the 20th century are frequently forgotten. In particular, I compare the AAA's recent exhibition to displays originally crafted for the 1915 and 1933 World's Fairs.  相似文献   

16.
17.
Question: This study evaluates historical changes in landscape structure and heterogeneity in subalpine forests. We use response to severe fires in 2001 and 2003, along with historical reconstructions to examine crown‐fire effects on landscape heterogeneity and to assess, comparatively, effects of fire exclusion management in the 20th century. Location: Subalpine forests of Kootenay National Park (KNP), Canadian Rockies. Methods: Using a landscape‐level model based on a fire‐origin stand age map, we reconstructed decadal burned areas within the landscape for 1750‐2000 (forming reconstructed landscapes). Landscape pattern was analysed for each reconstructed landscape map, and we compared landscape pattern indices (total area, number of patches, mean patch area, patch area variation, largest patch index, edge density, perimeter–area ratio, landscape shape index) with those in 2005 after recent large fires. Results: After large fires in 1926, connectivity of the KNP landscape increased and its diversity was quite low. After 2001 and 2003 fires, the post‐fire landscape of 2005 was highly heterogeneous in terms of size, variation, edge density and perimeter–area ratio of the remnant forest patches. Since the decline in occurrence of large fires after 1926 reflected a period of wet weather, fuel build‐up resulting from landscape homogenization within the 20th century landscape could not be attributed solely to fire exclusion. This period without fires greatly enhanced connectivity of late‐successional forests that finally burned in 2001/2003, but connectivity was within the historical range for these forests. The gradual increase in stand connectivity before recent large fires may indicate that fire exclusion was less responsible than often believed for fuel build‐up in these fire‐susceptible older forests. Conclusions: The large fires at the beginning of the 21st century are within the natural range of disturbances for this landscape, and do not stand out as “human‐induced disasters” in their effects on landscape patterns. Such stochastic large disturbances contribute to maintenance of highly heterogeneous landscape structure, which is important for many taxa and natural ecological processes. Identifying future probability of such large disturbances and their ecological roles should be incorporated into management of these dynamic, disturbance‐prone systems.  相似文献   

18.
The study represents palaeodemographic research of osteological material of 3304 individuals from the funds of the Anthropological Laboratory of the Institute of History of the University of Latvia in Riga, dating from the 7th to the 18th century AD. Compensated life expectancy at birth is varying between 20.3 and 22.2 years during the research period. Crude mortality has changed between 49.3 and 45% per hundred. In the early period (7th-13th century) there is a significant male prevalence (2.2-1.4); female life expectancy at the age of 20 is on average 6.6 years less than for males. This difference decreases to 5.4 years in the 13th-18th century. According to historical demography, female life span exceeded male only in the 2nd half of 19th century. The palaeodemographic data indicate that in the 7th-18th century, women in Latvia gave birth to a mean of 4-5 children (the figure includes childless women), of whom half, at most 2-2.5, reached reproductive age, on account of high child mortality. The net reproductive rate R0 (the number of descendants per individual of the parents' generation) varies between 1 and 1.25 in the study period. Concerning the completely excavated cemeteries of Lejasbiteni (7th-10h century) and Daudziesi (16th-17th century), it was possible to calculate the size and structure of the populations that had used these cemeteries. They were similar, having 45.3-49.9% of children up to an age of 14 and 24-28% individuals over the age of 30. According to historical demography, radical improvement of the demographic situation in Latvia began in the second half of the 19th century, when the process of demographic transition in Latvia started.  相似文献   

19.
We evaluated how litter raking removed basic nutrients from forest soils by simulating this historical silvicultural practice on two spruce stands (Picea abies) in the Czech Republic. Experimental litter raking depleted the soil pool of exchangeable base cation nutrients (Ca2+, Mg2+ and K+) by up to 31% after the first litter raking in 2003. A second litter raking in the following year further reduced the soil pool by up to 16%, and the third litter raking in 2005 reduced the pool by up to 6% more. These losses of base cations were substantially greater than their annual input into the forest soil (estimated as from total atmospheric deposition and mineral weathering) as well as their annual runoff. The concentration of Mg and Ca in spruce needless decreased considerably within 3 years from the beginning of the experiment. In addition, the observed litter chemistry was used to estimate historical nutrient removal from litter raking by applying them to historical records of litter removal rates. According to these calculations, the annual loss of total Ca, Mg and K from spruce stands would be from 40% to 100% of its present annual input into the soil, and from 50% to 190% of annual runoff. On the basis of previous results estimated by geochemical modeling, we found that the loss of base cations due to litter raking was similar to their leaching due to acid deposition. We conclude that long-term removal of litter as widely practiced throughout the 19th century in Central Europe may have been responsible for a loss of base cations equivalent to that caused by acid deposition during the 20th century.  相似文献   

20.
The name “Wampanoag” means “Eastern People” or “People of the First Light” in the local dialect of the Algonquian language. Once extensively populating the coastal lands and neighboring islands of the eastern United States, the Wampanoag people now consist of two federally recognized tribes, the Aquinnah and Mashpee, the state‐recognized Seaconke Wampanoag tribe, and a number of bands and clans in present‐day southern Massachusetts. Because of repeated epidemics and conflicts with English colonists, including King Philip's War of 1675–76, and subsequent colonial laws forbidding tribal identification, the Wampanoag population was largely decimated, decreasing in size from as many as 12,000 individuals in the 16th century to less than 400, as recorded in 1677. To investigate the influence of the historical past on its biological ancestry and native cultural identity, we analyzed genetic variation in the Seaconke Wampanoag tribe. Our results indicate that the majority of their mtDNA haplotypes belongs to West Eurasian and African lineages, thus reflecting the extent of their contacts and interactions with people of European and African descent. On the paternal side, Y‐chromosome analysis identified a range of Native American, West Eurasian, and African haplogroups in the population, and also surprisingly revealed the presence of a paternal lineage that appears at its highest frequencies in New Guinea and Melanesia. Comparison of the genetic data with genealogical and historical information allows us to reconstruct the tribal history of the Seaconke Wampanoag back to at least the early 18th century. Am J Phys Anthropol 142:579–589, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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