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1.
Núria Roura-Pascual Lluís Brotons A. Townsend Peterson Wilfried Thuiller 《Biological invasions》2009,11(4):1017-1031
Invasive species are known to influence the structure and function of invaded ecological communities, and preventive measures
appear to be the most efficient means of controlling these effects. However, management of biological invasions requires use
of adequate tools to understand and predict invasion patterns in recently introduced areas. The present study: (1) estimates
the potential geographic distribution and ecological requirements of the Argentine ant (Linepithema humile Mayr), one of the most conspicuous invasive species throughout the world, in the Iberian Peninsula using ecological niche
modeling, and (2) provides new insights into the process of selection of consensual areas among predictions from several modeling
methodologies. Ecological niche models were developed using 5 modeling techniques: generalized linear models (GLM), generalized
additive models (GAM), generalized boosted models (GBM), Genetic Algorithm for Rule-Set Prediction (GARP), and Maximum Entropy
(Maxent). Models for the eastern and western portions of the Iberian Peninsula were built using subsets of occurrence and
environmental data to investigate the potential for ecological niche differences between the invading populations. Our results
indicate geographic differences between predictions of different approaches, and the utility of ensemble predictions in identifying
areas of uncertainty regarding the species’ invasive potential. More generally, our models predict coastal areas and major
river corridors as highly suitable for Argentine ants, and indicate that western and eastern Iberian Peninsula populations
occupy similar environmental conditions.
相似文献
Núria Roura-PascualEmail: |
2.
The maintenance of exceptionally high numbers of folk varieties by the Piaroa people of the Venezuelan Amazon is considered.
We cataloged 113 manioc folk varieties, their nomenclature, use and relevant characters, revealing significant insights into
the role of manioc in Piaroa social life. Through a qualitative investigation of the cultivation, processing and symbolic
significance of manioc (Manihot esculenta) in two Piaroa regions over a period of 18 years, we have found that such agrobiodiversity can only be fully explained by
a combination of multiple factors, including pragmatic and ecological considerations, the subtle and complex diversity of
Piaroa manioc preparations and a variety of sociocultural factors, such as manioc’s role as a mediator of social relationships
and as a marker of cultural and social heritage.
相似文献
Stanford ZentEmail: |
3.
Peter Godfrey-Smith 《Biology & philosophy》2007,22(3):429-437
Jablonka and Lamb's claim that evolutionary biology is undergoing a ‘revolution’ is queried. But the very concept of revolutionary
change has uncertain application to a field organized in the manner of contemporary biology. The explanatory primacy of sequence
properties is also discussed.
相似文献
Peter Godfrey-SmithEmail: |
4.
Indigenous peoples of western Arnhem Land, central northern Australia, have detailed knowledge of the rock kangaroos of the region, species that are little known to science. Information about the ecology of the species is required for their conservation and management. Ethnoecological studies can assist senior indigenous people with transfer of knowledge and can give respect and meaningful employment to those involved. We used semidirected interviews in the regional vernacular, Bininj Kunwok, to record indigenous knowledge of the ecology of the four rock kangaroo species (Petrogale brachyotis, P. concinna, Macropus bernardus and M. robustus). Discussions focussed on habitat preferences, diet, activity patterns, reproduction, predation, and hunting practices. The ethnoecological knowledge of the rock kangaroo species was extensive, and both complemented and extended that reported in the scientific literature. In contrast to scientific understanding of taxonomy and ecology, consultants recognized the rock kangaroos as a natural group. They also described subtle differences in the species’ comparative ecology. The methodology used proved highly successful and we recommend recording indigenous knowledge of the ecology of fauna species in the local vernacular wherever possible. This study is one of the most comprehensive ethnozoological studies of a group of species undertaken in Australia.
相似文献
Wendy R. TelferEmail: |
5.
Sub-Antarctic Marion Island has had a permanent research station for 50 years and the islands Wandering Albatrosses have been intensively studied for 20 years. The reactions of breeding birds to approaches by a human on foot were recorded. Three response variables were calculated: intensity of vocal reaction (IVR), intensity of non-vocal reaction (INR) and overall response index (ORI). At 5 m from the nest, twice as many birds stood and/or vocalised as at 15 m. Nearest neighbour distance, age and gender did not explain individual variability of responses. Study colony birds had higher IVR scores than non-study colony birds; birds at colonies closest to the station had the highest ORI scores. A better breeding record was associated with lower IVR and ORI scores, but a causative relationship remains to be demonstrated. A minimum viewing distance of 25 m is recommended for breeding Wandering Albatrosses.
相似文献
Marienne S. de VilliersEmail: Fax: +27-21-6503434 |
John CooperEmail: |
Peter G. RyanEmail: |
6.
Debates over adaptationism can be clarified and partially resolved by careful consideration of the ‘grain’ at which evolutionary
processes are described. The framework of ‘adaptive landscapes’ can be used to illustrate and facilitate this investigation.
We argue that natural selection may have special status at an intermediate grain of analysis of evolutionary processes. The
cases of sickle-cell disease and genomic imprinting are used as case studies.
相似文献
Peter Godfrey-SmithEmail: |
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Mycena aphanes and Mycena exilis, belonging to section Filipedes and section Polyadelphia, are proposed as new species. They are described and illustrated and compared to other species in the two sections. Mycena aphanes is a strikingly characteristic Mycena with fulvous or yellowish brown colours of both pileus and stipe. Mycena exilis is characterized by its occurrence on fallen Salix leaves, a pale brown pileus, occasionally with a pale pink tinge, narrowly adnate lamellae, four-spored basidia, and the
presence of clamp connections.
相似文献
Gro GuldenEmail: |
10.
Brad E. Erisman Jorge A. Rosales-Casián Philip A. Hastings 《Environmental Biology of Fishes》2008,82(1):23-33
The sexual pattern and sexual development of the leopard grouper, Mycteroperca rosacea, were investigated from 483 specimens collected from the Gulf of California, Mexico. Histological and population data indicated
a gonochoric sexual pattern. Some juveniles passed through an immature bisexual phase of gonadal development, but no evidence
of post-maturational sex change was found. The immature bisexual phase is believed to be associated only with male development.
The size distribution and size at sexual maturity were similar for both males and females. In accordance with predictions
of the size-advantage model, the gonochoric sexual pattern of M. rosacea is likely influenced by its group-spawning mating system.
相似文献
Brad E. ErismanEmail: |
11.
Event-related brain potentials (ERP) are important neural correlates of cognitive processes. In the domain of language processing,
the N400 and P600 reflect lexical-semantic integration and syntactic processing problems, respectively. We suggest an interpretation
of these markers in terms of dynamical system theory and present two nonlinear dynamical models for syntactic computations
where different processing strategies correspond to functionally different regions in the system’s phase space.
相似文献
Peter beim GrabenEmail: |
12.
The Gitksan and Wet’suwet’en of Northwestern British Columbia formerly used landscape burning to manage patches of black huckleberry
(Vaccinium membranaceum), the most important plant resource of their seasonal round. In view of its significance one might postulate that managed
sites would conform to a biophysical or ecological type to maximize return for effort. However, a survey of a number of traditionally
managed sites indicated that managed sites are characterized by wide variation in biophysical attributes including elevation,
aspect and moisture regime, while proximity to fishing sites, village sites, or sites for harvest of alpine resources proved
to be a common factor in known historic berry patch sites. We conclude that characterization of the ideal site type for aboriginal
V. membranaceum management must include the economy and social institutions of the local First Nations and requires an enhanced appreciation
for the sophistication of the strategies and techniques employed in their management and utilization of the species.
相似文献
Leslie Main Johnson (Corresponding author)Email: |
13.
In 2001 Carijoa riisei, an octocoral native to the tropical Western Atlantic, was discovered overgrowing black corals in the Au’au Channel in Hawaii.
In this paper data from a 2001 survey are reanalyzed and combined with new data from 2003 and 2004 to assess the ecological
impact in greater detail. C. riisei differentially affected reproductively mature black coral colonies with maximum impact between 80 and 105 m. The pattern
of C. riisei overgrowth on black corals and C. riisei on the substrata appears to be bounded by high irradiance in shallow water and cold temperature in deep water. Evidence suggests
that the C. riisei settlement on black corals is facilitated by other epifauna. Once established, C. riisei spreads vegetatively and smothers the coral. The success of the C. riisei invasion appears to be unaided by anthropogenic disturbance and is at least partially attributable to Hawaii’s depauperate
shallow-water (<100 m) octocoral fauna.
相似文献
Richard W. GriggEmail: |
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Managing Plant Resources: How Intensive Can it be? 总被引:3,自引:2,他引:1
Martha Sofía González-Insuasti Javier Caballero 《Human ecology: an interdisciplinary journal》2007,35(3):303-314
Previous studies have shown there is a wide spectrum of incipient management practices between gathering and agriculture,
that include resources commonly considered “wild.” Based on the study of 20 species used as foodstuffs in the community of
Santa María Tecomavaca (Mexico), we evaluated nonagricultural management forms such as gathering, incipient nonselective management,
incipient selective management and occasional ex situ cultivation to learn if they represent a gradient in the intensity of manipulation of a resource. The way in which the intensity
of manipulation of a resource can vary as a function of cultural importance and the species’ biology was also analyzed. Using
an index that measures the intensity of management of a resource, it has been established that the degree of intensity depends
on: the specialization of the practices directed to the environment as well as to the individuals; the number of persons performing
these practices; and the number of different practices taking place. The degree of management intensity is also a consequence
of the joint action of cultural importance and of species’ biology.
相似文献
Martha Sofía González-InsuastiEmail: |
16.
Ewa Puchalska Barbara Czajkowska Magorzata Kiekiewicz 《Acta Physiologiae Plantarum》2008,30(2):225-232
Our investigations suggest that the usually observed avoidance by O. ununguis of current year’s twigs of P. glauca ‘Conica’ as a place for feeding and development may be connected with their morphological and anatomical structure as well
their biochemical composition. Needles of the current year’s twigs were covered with a thicker layer of wax and formed more
extensive epidermis cell walls, in comparison with needles of 1-year-old twigs. Young needles also showed lower concentration
of reducing sugars and soluble proteins, which might additionally reduce their nutritional suitability for mite development.
Differences were also found between the 1-year-old growth and current growth in contribution of essential oils and a range
of other compounds. Further analyses of the effect of these compounds on mite behavior may provide additional explanation
of the feeding preferences of the mite.
相似文献
Barbara CzajkowskaEmail: |
17.
Harold Levrel Christian Kerbiriou Denis Couvet Jacques Weber 《Biodiversity and Conservation》2009,18(7):1719-1732
Sustainability is said to be the science of integration, be it integration of scale, discipline or of stakeholders’ interests.
One way to integrate such diverse elements is to develop sustainable development indicators. Numerous national and international
organizations have attempted to develop such indicators, among which interaction indicators are of critical importance because
they enable us to link up human activities, ecological dynamics, and social goals. Among the various ways to develop such
indicators, the most common ones are the pressure–state–response (PSR) indicators, as well as others coming from this framework.
With realistic methodology one shall observe how PSR indicators might appear as an operational tool to face rapid social and
ecological changes within a French biosphere reserve in Brittany. Results suggest that such a framework is insufficient to
describe, understand and manage social and ecological interactions.
相似文献
Harold LevrelEmail: |
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19.
Danwei as a cornerstone of Chinese urban society has received great research attention. The relationship between the Danwei and psychiatric patients, however, remains unclear. This article aims to shed light on the subject with an integrated micro–macro
approach. It introduces a historical understanding of mental health in urban China under the “economic state in transition”
framework. A detailed case study in clinical sociology is provided to reveal the many social factors affecting the experience
of a schizophrenic patient and his significant others. A changing role of the Danwei is hypothesized and validated with qualitative data. The Danwei was shown to have changed significantly before the mid-1990s, yet it still played a major role in urban workers’ lives, including
those of psychiatric patients, and even more so in people’s expectations. This lends support to the need for a more responsive
public policy to address various social issues brought about by economic reform, with the learning of worldwide experiences
including “community care,” “social support” and “social rehabilitation.” Implications for social research, policymaking and
professional practice are discussed.
相似文献
Robert SévignyEmail: |
20.
Richard J. Robins Roland Molinié Renata A. Kwiecień Piotr Paneth Jacques Lebreton Trixie A. Bartholomeusz Albrecht Roscher Birgit Dräger Anna-Carolin Meier François Mesnard 《Phytochemistry Reviews》2007,6(1):51-63
The reaction of N-demethylation plays an important role in the degradation of some alkaloids in a number of organisms. This review presents
how our understanding of the N-demethylation of nicotine in plants has been improved through studies in cell cultures of Nicotiana plumbaginifolia and N. glutinosa using a variety of isotopic techniques. The overall aim is to understand how metabolism recycles the alkaloid skeleton, both
in terms of the metabolic route(s) exploited and the reaction mechanisms of the enzymes involved. The former has been approached
using high-resolution 2-dimensional NMR and GC-MS methods; the latter by determining kinetic isotope effects and modelling
the potential reaction steps. It appears that the mechanism for nicotine demethylation in plants is similar to but has significant
differences from that described for mammals and Pseudomonas bacteria. These differences are discussed.
相似文献
Richard J. RobinsEmail: |