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Precipitation and aridity index regulating spatial patterns of
Precipitation and aridity index regulating spatial patterns of

... analyze the relationship among environment factors, as shown in Table 1. As a result, annual mean ...
Consumers Control Diversity and Functioning of a Natural Marine
Consumers Control Diversity and Functioning of a Natural Marine

... grazing the highly abundant and palatable Ulva, which apparently suppresses the productivity of neighboring algae. In terrestrial ecosystems, insect grazing can decrease plant evenness if insects target moderately abundant species [40]. Moreover, insectmediated increases in plant evenness can result ...
Red-headed Woodpecker (Melanerpes erythrocephalus)
Red-headed Woodpecker (Melanerpes erythrocephalus)

... This species is important to the maintenance of biodiversity because the cavities it excavates in trees provide sleeping and nesting sites for many other species. It also plays a significant role in maintaining the deciduous forest ecosystems of eastern North America by dispersing large quantities o ...
Reinventing mutualism between humans and wild fauna: insights
Reinventing mutualism between humans and wild fauna: insights

... relations has virtually disappeared worldwide. Here, we describe the mutualistic relationship between humans and the globally threatened Egyptian vulture in Socotra, Yemen. By analyzing both the spatial distribution of vultures and the amount of human byproducts they consume, we show that human acti ...
Northern Royal albatross EN1.1 - Agreement on the Conservation of
Northern Royal albatross EN1.1 - Agreement on the Conservation of

... BREEDING SITES: THREATS The three breeding islands in the Chatham group which contain over 99% of the population are privately owned. Table 6. Summary of known threats causing population level changes at the main breeding sites of D. sanfordi. This table is based on unpublished DOC data submitted to ...
Seedling survival and seed size
Seedling survival and seed size

... this SESRE is large relative to the range of predicted values (logit-transformed, −2.6 to −1.1) fitted by the random effects logistic regression). Phylogenetic regression, however, showed no significant relationship between seed mass and the proportion of individuals surviving emergence (P = 0.11, d ...
Strasbourg, 22 May 2002
Strasbourg, 22 May 2002

... therefore is widely considered to be the major determinant both of species distributions (e.g. MacArthur 1972, Gaston 2003) and of global biodiversity patterns (e.g. Currie 1991, Hawkins et al. 2003). As small, ectothermic organisms, invertebrates are particularly sensitive to fluctuations in temper ...
threatened and declining birds in the new south wales sheep
threatened and declining birds in the new south wales sheep

... low-shrub feeders and dwellers – only three species are classified as canopy foragers, and two are aerial insectivores (the woodswallows). There is a predominance of insectivores among the ground feeders (15) and among all 20 Decliners, but seed-eaters are as well represented as expected from their ...
Landscape elements as potential barriers and corridors for bees
Landscape elements as potential barriers and corridors for bees

... with isolation level as fixed factor and site as random factor. Response variables were the abundance and species richness of wild bees in the pan traps and the colonization, species richness and parasitism rates of trap-nesting bees and wasps and the functional groups of wasps. The random factor co ...
Sensitivity of copepod populations to bottom-up and top
Sensitivity of copepod populations to bottom-up and top

... and Ford, 2006). The objective of this study was to assess the relative importance of bottom-up and top-down controls of different copepod species in different areas of the GoM – GB regions. Earlier life-table analysis by Kiørboe and Sabatini (Kiørboe and Sabatini, 1994) has suggested that copepod p ...
Avian predators are less abundant during periodical cicada
Avian predators are less abundant during periodical cicada

... ‘‘repel’’ hypothesis, proposed by Simmons et al. 1971). Third, bird numbers may be regionally lower in emergence years, even to some extent outside the range of cicadas, for reasons unrelated to the current cicada emergence event (the ‘‘true decline’’ hypothesis). All three hypotheses are consistent ...
2009rat
2009rat

... The ratio of E. rosea shells chewed by rats over the total number of shells found in each plot is shown over time by site (next figure). If rats are, in fact, consuming high numbers of E. rosea then this should be reflected in a higher proportion of empty shells observed to be chewed rather than int ...
Biodiversity and Ecosystem Functioning: Basic
Biodiversity and Ecosystem Functioning: Basic

... Species are primarily redundant: Loss of species is compensated for by other species with a similar function. Conversely, the addition of such species adds nothing new to the system. The graphical presentation show an asymptotic relationship in which a major proportion is insensitive to changes in d ...
Notes from Introduction - Forest Landscape Ecology Lab
Notes from Introduction - Forest Landscape Ecology Lab

... concepts of interacting species and physical properties. 4) Theories of spatial dynamics in forests (disturbance and succession) illustrating change through time. Patch- LS surface area different from majority surroundings (matrix). Principles of LE (Risser et al. 1984): 1) Relationship of spatial p ...
Chapter 2 Diatoms in the pelagic and benthic environment
Chapter 2 Diatoms in the pelagic and benthic environment

... 2.2.2b.1. Enumeration of diatom propagules from the sediments From a technological viewpoint, finding diatom resting stages in sediments by normal microscopic observation is not easy because of the problem of cell aggregation and concealment by extraneous material. Enumeration of diatom cells from s ...
Quadrats Online: Teacher Notes
Quadrats Online: Teacher Notes

... A quadrat is a tool used to record the abundance or density of a particular species in a study area. In some instances it may be possible to simply count the number of organisms of a particular species in an area. However, in most cases counting all of the organisms would not be practical and other ...
Rethinking patch size and isolation effects: the habitat amount
Rethinking patch size and isolation effects: the habitat amount

... (like the curve for islands) or shallower (like the curve for sample areas within continuous habitat)? If the latter, we can hypothesize that the species–area curve for habitat patches primarily results from the sample area effect, where larger patches represent larger sample areas. This is an impor ...
Growth Rings in the Roots of Temperate Forbs are Robust Annual
Growth Rings in the Roots of Temperate Forbs are Robust Annual

... Counting the number of annual rings in the roots of forbs has been used for age determination, demographic analyses, and investigations into population development (e.g., Boggs and Story, 1987; Dietz and Ullmann, 1998; Dietz et al. 1999; Dietz, 2002). Furthermore, determination of plant age along en ...
Action Statement
Action Statement

... (1999) suggests this impact may be considerable given the open habitat occupied by the lizards, and the fact that they are predominantly nocturnal, as are these predators. The use of insecticides in or near areas where the species occurs may reduce the amount of available prey. The Hooded Scaly-foot ...
Hooded Scaly-foot (Pygopus nigriceps)
Hooded Scaly-foot (Pygopus nigriceps)

... (1999) suggests this impact may be considerable given the open habitat occupied by the lizards, and the fact that they are predominantly nocturnal, as are these predators. The use of insecticides in or near areas where the species occurs may reduce the amount of available prey. The Hooded Scaly-foot ...
Relative importance of endogenous and exogenous mechanisms in
Relative importance of endogenous and exogenous mechanisms in

... Abstract: The competitive exclusion principle poses the pressing question of how biodiversity is maintained in nature. Many mechanisms have been proposed to explain diversity and to resolve what has become known as the “paradox of the plankton”. We propose a dichotomy among these mechanisms in order ...
Predator–prey relationships and responses of ungulates and their
Predator–prey relationships and responses of ungulates and their

... The influence of livestock grazing on native wildlife has been a matter of considerable debate (e.g. Saberwal, 1996; Mishra and Rawat, 1998; Voeten, 1999; Prins, 2000). However, studies conducted in somewhat similar habitat types in tropical forests in India have documented substantial increases in ...
CHOOSING THE APPROPRIATE SCALE OF RESERVES FOR
CHOOSING THE APPROPRIATE SCALE OF RESERVES FOR

... plants, and invertebrates appeared on the ESA list (168), yet the IUCN (171) lists over 4500 species of plants alone that are at risk of extinction within the United States. Given that arthropod diversity far outstrips plant diversity, and that plants at risk outnumber all listed species 4 to 1, the ...
Elevated carbon dioxide is predicted to promote model
Elevated carbon dioxide is predicted to promote model

... and nutrient cycling. Similar frameworks to model competition have been widely used (Miki and Kondoh 2002; Rastetter and Agren 2002; Herbert et al. 2004; Daufresne and Hedin 2005; Ju and DeAngelis 2009). We simulated the effects of eCa on long-term outcomes of interspecific competition using the pla ...
Biotic and abiotic interactions controlling starfish
Biotic and abiotic interactions controlling starfish

... Directly or indirectly, the role of sea water temperature may be a factor causing the formation of starfish aggregations. Fluctuations in the numbers of Asterias juveniles in the Bay of Douarnenez during our study were correlated with water temperatures in Brittany (Guillou, 1990). From 1981 to 1984 ...
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Occupancy–abundance relationship

In ecology, the occupancy–abundance (O–A) relationship is the relationship between the abundance of species and the size of their ranges within a region. This relationship is perhaps one of the most well-documented relationships in macroecology, and applies both intra- and interspecifically (within and among species). In most cases, the O–A relationship is a positive relationship. Although an O–A relationship would be expected, given that a species colonizing a region must pass through the origin (zero abundance, zero occupancy) and could reach some theoretical maximum abundance and distribution (that is, occupancy and abundance can be expected to co-vary), the relationship described here is somewhat more substantial, in that observed changes in range are associated with greater-than-proportional changes in abundance. Although this relationship appears to be pervasive (e.g. Gaston 1996 and references therein), and has important implications for the conservation of endangered species, the mechanism(s) underlying it remain poorly understood
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