Abstract:
:Analysis of the degree of order in species assemblages in terms of nested subsets has received increased interest during the last decade. However, recently a series of papers have questioned the validity of methods employed for testing whether observed patterns deviate from random expectations. The current view seems to be that the randomization procedure should control for both number of species per site and species frequencies. The randomization procedures used also choose to keep the total number of observations constant in each resample. In this paper I question some of these assumptions when analyzing species-by-site matrices for detecting whether the biota is significantly nested or not. My basic assumption is that the observed species frequency is only an estimate of the probability of occurrence for the particular species. For a test of degree of nestedness all sites should be regarded as being equal. To what extent size, isolation or habitat quality may influence species distribution is a secondary question if nestedness can be statistically proven. This implies that generation of random matrices should only consider the frequency of the species (as an estimate of their probability of occurring in any patch). Such matrices are computationally simple and besides providing a test of nestedness also open the possibility of testing whether the range in species richness is smaller or larger than expected under random expectations. The choice of null model for the test should always be viewed in relation to the question asked. If nestedness is concerned the methods proposed here should be used. However, if other questions are at hand the restrictions of previous approaches may be valid. This is for instance the case if pairwise species co-occurrences are analyzed. In this case, the richness of each site should obviously be incorporated in the randomization to control for the higher probability of co-occurrence at species-rich sites.
journal_name
Oecologiajournal_title
Oecologiaauthors
Jonsson BGdoi
10.1007/s004420000601subject
Has Abstractpub_date
2001-05-01 00:00:00pages
309-313issue
3eissn
0029-8549issn
1432-1939pii
10.1007/s004420000601journal_volume
127pub_type
杂志文章相关文献
OECOLOGIA文献大全abstract::Populations ofDipodomys microps andD. merriami in eastern California (37°11'N. Lat.) are active on the surface throughout the night and during the whole year. These two species, and the males and females within each species, show no significant differences in times of beginning or end of activity. Beginning and end of...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00572754
更新日期:1976-06-01 00:00:00
abstract::In both single- and mixed-species social groups, certain participants are known to play important roles in providing benefits. Identifying these participants is critical for understanding group dynamics, but is often difficult with large roving social groups in the wild. Here, we develop a new approach to characterize...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-014-3045-0
更新日期:2014-11-01 00:00:00
abstract::Seed dispersal is an important ecosystem function, but it is contentious how structural and functional diversity of plant and bird communities are associated with seed-dispersal functions. We used structural equation models to test how structural (i.e., abundance, species richness) and functional diversity (i.e., func...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-018-4324-y
更新日期:2019-02-01 00:00:00
abstract::Marion Island (47°S, 38°E) has one of the most oceanic climates on earth, with consistently low air temperatures, high precipitation, constantly high humidity, and low incident radiation. Since 1968 mean surface air temperature has increased significantly, by 0.025° C year-1. This was strongly associated with correspo...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00317338
更新日期:1990-11-01 00:00:00
abstract::Canopy structure and tree species diversity, shaped by succession, disturbance, and community composition, are linked to numerous ecosystem functions, including net primary production (NPP). Understanding of how ecosystem structural metrics are interrelated and mechanistically link to NPP, however, is incomplete. We c...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-018-4236-x
更新日期:2018-10-01 00:00:00
abstract::We compared above-ground allocation patterns in mature shrubs of Banksia hookeriana from three 13-year-old populations, growing on nutrient-impoverished sands to determine whether C (dry mass) could be a substitute for mineral nutrients (N, P, K, Ca, Mg and NA). The percentage of reproductive structures to total above...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00328789
更新日期:1996-01-01 00:00:00
abstract::Tooth enamel apatite carbonate carbon and oxygen isotope ratios of modern kangaroos (Macropus spp.) collected on a 900-km latitudinal transect spanning a C(3)-C(4) transition zone were analysed to create a reference set for palaeoenvironmental reconstruction in southern Australia. The carbon isotope composition of ena...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-012-2425-6
更新日期:2013-02-01 00:00:00
abstract::The mortality and physiological status (body water content) of Asellus aquaticus (Isopoda) and Gammarus pulex (Amphipoda) were measured after 25 days exposure in 20 natural streams with a pH range of 4.3-7.5 and a colour range of 8-280 mg Pt L-1. In addition, the effects of keeping the animals as single species or tog...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00317482
更新日期:1990-03-01 00:00:00
abstract::Dusky-footed woodrats (Neotoma fuscipes) and desert woodrats (N. lepida) experience pronounced seasonal variations in the aridity of their habitats. The effects of seasonal aridity upon the water conserving abilities of these species were assessed through measurements of water conserving abilities and kidney structure...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00346564
更新日期:1979-01-01 00:00:00
abstract::We used a complete block design to experimentally study direct and indirect interactions in a three trophic-level freshwater system consisting of a top predator, the green sunfish, Lepomis cyanellus, an intermediate predator, small-mouthed salamander larvae, Ambystoma barbouri, and prey, hatchling isopods, Lirceus fon...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00323765
更新日期:1991-02-01 00:00:00
abstract::The CO2 assimilation of primary foliage of red maple (Acer rubrum L.) and red oak (Quercus rubra L.), and of regrowth foliage produced in response to simulated insect defoliation, was measured throughout the season by infrared gas analysis: parallel measurements of leaf conductance were obtained by ventilated diffusio...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00379555
更新日期:1983-03-01 00:00:00
abstract::We demonstrate that natural heat stress on wild larval Drosophila melanogaster results in severe developmental defects in >10% of eclosing adults, and that increased copy number of the gene encoding the major inducible heat shock protein of D. melanogaster, Hsp70, is sufficient to reduce the incidence of such abnormal...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s004420050935
更新日期:1999-11-01 00:00:00
abstract::Like many polyphagous herbivores, individuals of Sarasinula plebeia (Fischer) (Soleolifera: Veronicellidae) consume a variety of plant species that may differ in nutritional content. In this study we determined the ability of these slugs to compensate for such variation in diet composition. Dilution with water of an a...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00320809
更新日期:1991-10-01 00:00:00
abstract:: Fluorogenic substrate analogues (MUF substrates) are very sensitive in detecting hydrolytic enzymes. This method was adapted for the quantitative analysis of extracellular enzymes in snails and other animals. It was then used to determine cellobiase, chitobiase, protease, esterase, phosphatase and lipase in the diges...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s004420050055
更新日期:1996-12-01 00:00:00
abstract::We investigated the effect of increased N-supply on productivity and potential litter decay rates of Carex species, which are the dominant vascular plant species in peatlands in the Netherlands. We hypothesized that: (1) under conditions of N-limited plant growth, increased N-supply will lead to increased productivity...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00341342
更新日期:1995-12-01 00:00:00
abstract::The population dynamics of Antarctic seabirds are influenced by variations in winter sea ice extent and persistence; however, the type of relationship differs according to the region and the demographic parameter considered. We used annual presence/absence data obtained from 1,138 individually marked birds to study th...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-009-1387-9
更新日期:2009-08-01 00:00:00
abstract::For many amphibians, high temperatures and limited precipitation are crucial habitat characteristics that limit species ranges and modulate life-history characteristics. Although knowledge of the ability of amphibians to cope with such environmental harshness is particularly relevant in the light of ongoing environmen...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-015-3258-x
更新日期:2015-07-01 00:00:00
abstract::Agricultural intensification (AI) is currently a major driver of biodiversity loss and related ecosystem functioning decline. However, spatio-temporal changes in community structure induced by AI, and their relation to ecosystem functioning, remain largely unexplored. Here, we analysed 16 quantitative cereal aphid-par...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-012-2366-0
更新日期:2012-12-01 00:00:00
abstract::Cellulose toilet roll baits were exposed in three different subhabitats at Nylsvley Reserve, northern Transvaal, and respective attacks by up to eight species of termites are described and illustrated. In broad-leaved savanna attack was principally by Microcerotermes, a slow feeder that attacked rolls throughout the y...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00349023
更新日期:1982-01-01 00:00:00
abstract::The climatic control of productivity for two populations of the lichen Cetraria cucullata (Bell.) Ach. growing in the arctic tundra of northern Alaska (70°28'N, 157°23'W) was examined. Respiratory losses of carbon vary with tissue temperature, tissue water content, and time since wetting. Potential net photosynthetic ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00348040
更新日期:1981-08-01 00:00:00
abstract::Energy metabolism (oxygen consumption) in acclimated juvenile yellow banded and unbanded Cepaea hortensis Müll. was measured at 5°, 10°, 15°, 20°, and 25°C with Englemann respirometers. Metabolic rates were also measured after abrupt temperature changes from 5° to 20° and from 25° to 10°C.Energy metabolism in the two ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00345000
更新日期:1979-08-01 00:00:00
abstract::The structure and seasonal dynamics of phytoplankton communities in the littoral zone were compared between oligotrophic and eutrophic lakes in the southeastern United States. Differences in diversity and species composition between lakes could be ascribed to long-term variation in nutrients corresponding to trophic s...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00380005
更新日期:1982-09-01 00:00:00
abstract::Many studies have shown that nonlethal predator effects such as trait-mediated interactions (TMIs) can have significant impacts on the structure and function of communities, but the role that environmental conditions play in modulating the scale and magnitude of these effects has not been carefully investigated. TMIs ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-008-0995-0
更新日期:2008-05-01 00:00:00
abstract::The effects of bannertail kangaroo rat (Dipodomys spectabilis) mounds and associated soil-surface disturbance on plant species composition and diversity in the Chihuahuan Desert were examined with multivariate analysis. Kangaroo rat mounds created disturbance gaps and contributed to local species diversity by creating...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00328605
更新日期:1996-04-01 00:00:00
abstract::There is considerable theoretical evidence that a trade-off between competitive and colonization ability enables species coexistence. However, empirical studies testing for the presence of a competition-colonization (CC) trade-off and its importance for species coexistence have found mixed results. In a microcosm expe...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-011-2013-1
更新日期:2011-11-01 00:00:00
abstract::Mature growth-phase internodes of Alaska paper birch (Betula resinifera) are preferred by the snowshoe hare (Lepus americanus) over juvenile growth-phase internodes due to the low food value of the latter. While the mature over juvenile preferencec cannot be explained by the levels of inorganic nutrients or gross chem...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00384463
更新日期:1984-12-01 00:00:00
abstract::Life history changes may change resource use. Such shifts are not well understood in the dung beetles, despite recognised differences in larval and adult feeding ability. We use the flightless dung beetle Circellium bacchus to explore such shifts, identifying dung sources of adults using DNA metabarcoding, and compari...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-018-4203-6
更新日期:2018-09-01 00:00:00
abstract::Although an increase in competition is a common cost associated with intraspecific crowding, spatial aggregation across food-limited resource patches is a widespread phenomenon in many insect communities. Because intraspecific aggregation of competing insect larvae across, e.show $132#g. fruits, dung, mushrooms etc., ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1629-9
更新日期:2004-08-01 00:00:00
abstract::Nitrogen use efficiency (NUE) has been widely used to study the relationship between nitrogen uptake and dry mass production in the plant. As a subsystem of plant nitrogen use efficiency (NUE), I have defined leaf-level NUE as the surplus production (gross production minus leaf respiration) per unit amount of nitrogen...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-011-2223-6
更新日期:2012-07-01 00:00:00
abstract::This paper presents tests of a model of wound-induced defence in herbaceous plants. Many studies have reported both chemical changes in leaves and changes in the behaviour and/or physiology of herbivores as a result of wounding leaves. These studies and others have led to the development of various models to explain w...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/BF00333221
更新日期:1996-10-01 00:00:00