scholarly journals Features of the population organization of Myricaria bracteata in the riverbed of the Ursul River (Gorny Altai)

2021 ◽  
Vol 38 ◽  
pp. 00076
Author(s):  
Elena M. Lyakh ◽  
Alexey Yu. Astashenkov
Keyword(s):  
Abiotic Factors ◽  
Demographic Parameters ◽  
Central Altai ◽  
Ontogenetic Structure ◽  
Gorny Altai ◽  
Population Organization ◽  
River Bend

The article represents the analysis of the ontogenetic composition and demographic parameters of 3 cenopopulations of Myricaria bracteata in the riverbed of the Ursul River (Central Altai). It was found that the ontogenetic structure and density of individuals depend on the degree of formation of the phytocenosis and the influence of abiotic factors (features of the substrate, river bend). The invasive cenopopulation formed in a bend of the river in the absence of a phytocenotic pressure; the young normal cenopopulation formed in the river deflection on the grasscover stony shore, and the invasive-regressive cenopopulation formed on an island washed by the river.

scholarly journals Study of some demographic parameters of Bactrocera (Dacus oleae); Test of a new food attractant in a trapping method

2019 ◽  
Vol 9 (3) ◽  
pp. 13-20
Author(s):  
A. Achouche ◽  
F. Abbassi ◽  
A. Benzahra ◽  
Z. Djazouli
Keyword(s):  
Abiotic Factors ◽  
The Other ◽  
Demographic Parameters ◽  
Olive Fly ◽  
Maximum Value ◽  
Other Hand ◽  
Yellow Color ◽  
Trapping Method ◽  
High Emergence ◽  
High Emergence Rate

This study focuses on the observation of changes in the demographic parameters of olive fly over time in two regions, Mitidja and Mezghana region, the method consists in identifying certain biotic and abiotic factors that can play a role on the variations of these parameters; on the other hand we tested new food attractiveness in a trapping method. The Results showed that the demographic parameters (emergence, parasitism and mortality) are influenced by the year and by the region factor with a very high emergence rate above 50%; On the other hand, the rate of parasitism remains low with a maximum value of 33.23% recorded in Mezghenna, regarding nymphal mortality the maximum value is recorded in Chebacheb with 26.44%. Furthermore, the study of the efficiency of nitrogen fertiliser (Urea 46 unit) on the catches of adults showed us that the best concentration of attraction is 6%; on the other hand, the yellow color of the traps positively influences the catches of Bactroceraoleae.

scholarly journals The structure and state of populations of Iris pumila L. in the Samara region

2020 ◽  
Vol 19 (2) ◽  
pp. 302-306
Author(s):  
V. N. Ilyina
Keyword(s):  
Rare Species ◽  
Demographic Parameters ◽  
Ontogenetic Structure ◽  
Iris Pumila

Data on the ontogenetic structure of natural coenopopulations of the rare species Iris pumila L. arepresented. Ontogenetic spectra, demographic parameters, and the type of coenopopulations are determined by the “deltaomega” criterion. Of the 30 cenopopulations studied, 18 are mature, 5 are transitional, 4 are aging, 3 are ripening. Averagedensity – 2.8 individuals per 1 m2.

Demography of common toads after local extirpation of co-occurring midwife toads

2014 ◽  
Vol 35 (3) ◽  
pp. 293-303 ◽  
Author(s):  
Jaime Bosch ◽  
Saioa Fernández-Beaskoetxea ◽  
Rick D. Scherer ◽  
Staci M. Amburgey ◽  
Erin Muths
Keyword(s):  
Abiotic Factors ◽  
High Elevation ◽  
Bufo Bufo ◽  
Demographic Parameters ◽  
Population Survival ◽  
The Common ◽  
Midwife Toad ◽  
Local Extirpation ◽  
High Elevations ◽  
Management And Conservation

Estimating demographic parameters like survival or recruitment provides insight into the state and trajectory of populations, but understanding the contexts influencing those parameters, including both biotic and abiotic factors, is particularly important for management and conservation. At a high elevation national park in Central Spain, common toads (Bufo bufo) are apparently taking advantage of the near-extirpation of the midwife toad (Alytes obstetricans), as colonization into new breeding ponds is evident. Within this scenario, we expected demographic parameters of common toad populations to be affected favorably by the putative release from competition. However, we found the population growth rate was negative in 4 of 5 years at the long-standing population; survival probability at the long-standing population and newly-colonised breeding ponds was lower than reported for other toads living at high elevations and the probability of recruitment was inadequate to compensate for the survival rate in maintaining a positive trajectory for either of the breeding ponds. We assessed weather covariates and disease for their contribution to the context that may be limiting the common toad’s successful use of the niche vacated by the midwife toad.

Coral husbandry for ocean futures: leveraging abiotic factors to increase survivorship, growth, and resilience in juvenile Montipora capitata

2021 ◽  
Vol 657 ◽  
pp. 123-133
Author(s):  
JR Hancock ◽  
AR Barrows ◽  
TC Roome ◽  
AS Huffmyer ◽  
SB Matsuda ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Larval Rearing ◽  
Abiotic Conditions ◽  
Montipora Capitata ◽  
Reef Restoration ◽  
Juvenile Corals ◽  
Bleaching Response ◽  
The Face ◽  
Survival And Growth ◽  
Global And Local

Reef restoration via direct outplanting of sexually propagated juvenile corals is a key strategy in preserving coral reef ecosystem function in the face of global and local stressors (e.g. ocean warming). To advance our capacity to scale and maximize the efficiency of restoration initiatives, we examined how abiotic conditions (i.e. larval rearing temperature, substrate condition, light intensity, and flow rate) interact to enhance post-settlement survival and growth of sexually propagated juvenile Montipora capitata. Larvae were reared at 3 temperatures (high: 28.9°C, ambient: 27.2°C, low: 24.5°C) for 72 h during larval development, and were subsequently settled on aragonite plugs conditioned in seawater (1 or 10 wk) and raised in different light and flow regimes. These juvenile corals underwent a natural bleaching event in Kāne‘ohe Bay, O‘ahu, Hawai‘i (USA), in summer 2019, allowing us to opportunistically measure bleaching response in addition to survivorship and growth. This study demonstrates how leveraging light and flow can increase the survivorship and growth of juvenile M. capitata. In contrast, larval preconditioning and substrate conditioning had little overall effect on survivorship, growth, or bleaching response. Importantly, there was no optimal combination of abiotic conditions that maximized survival and growth in addition to bleaching tolerances. This study highlights the ability to tailor sexual reproduction for specific restoration goals by addressing knowledge gaps and incorporating practices that could improve resilience in propagated stocks.

Characterizing the impact of recovering sea otters on commercially important crabs in California estuaries

2020 ◽  
Vol 655 ◽  
pp. 123-137
Author(s):  
TM Grimes ◽  
MT Tinker ◽  
BB Hughes ◽  
KE Boyer ◽  
L Needles ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Sea Otter ◽  
Dungeness Crab ◽  
Sea Otters ◽  
Elkhorn Slough ◽  
Enhydra Lutris Nereis ◽  
Crab Abundance ◽  
Population Sizes ◽  
Commercially Important ◽  
The Impact

Protective legislation and management have led to an increase in California’s sea otter Enhydra lutris nereis population. While sea otter recovery has been linked to ecosystem benefits, sea otter predation may negatively affect commercially valuable species. Understanding the potential influence of sea otters is of particular importance as their range expands into estuaries that function as nurseries for commercially valuable species like Dungeness crab Metacarcinus magister. We consider how sea otter predation has affected the abundance and size of juvenile Dungeness crab in Elkhorn Slough, California, USA, and analyzed cancrid crab abundance and size across 4 California estuaries with and without sea otters to understand how biotic and abiotic factors contribute to observed variation in crab size and abundance. We compared trends in southern sea otters relative to Dungeness crab landings in California to assess whether increasing sea otter abundance have negatively impacted landings. In Elkhorn Slough, juvenile Dungeness crab abundance and size have declined since 2012, coinciding with sea otter population growth. However, the impact of sea otters on juvenile Dungeness crab size was habitat-specific and only significant in unvegetated habitat. Across estuaries, we found that cancrid crab abundance and size were negatively associated with sea otter presence. While abiotic factors varied among estuaries, these factors explained little of the observed variation in crab abundance or size. Although we found evidence that sea otters can have localized effects on cancrid crab populations within estuaries, we found no evidence that southern sea otters, at recent population sizes, have negatively impacted Dungeness crab landings in California from 2000-2014.

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