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Insects ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 94
Author(s):  
Mikhail V. Kozlov ◽  
Vitali Zverev ◽  
Vladimir I. Gusarov ◽  
Daniil I. Korobushkin ◽  
Nina P. Krivosheina ◽  
...  

Latitudinal gradients allow insights into the factors that shape ecosystem structure and delimit ecosystem processes, particularly climate. We asked whether the biomass and diversity of soil macrofauna in boreal forests change systematically along a latitudinal gradient spanning from 60° N to 69° N. Invertebrates (3697 individuals) were extracted from 400 soil samples (20 × 20 cm, 30 cm depth) collected at ten sites in 2015–2016 and then weighed and identified. We discovered 265 species living in soil and on the soil surface; their average density was 0.486 g d·w·m−2. The species-level diversity decreased from low to high latitudes. The biomass of soil macrofauna showed no latitudinal changes in early summer but decreased towards the north in late summer. This variation among study sites was associated with the decrease in mean annual temperature by ca 5 °C and with variation in fine root biomass. The biomass of herbivores and fungivores decreased towards the north, whereas the biomass of detritivores and predators showed no significant latitudinal changes. This variation in latitudinal biomass patterns among the soil macrofauna feeding guilds suggests that these guilds may respond differently to climate change, with poorly understood consequences for ecosystem structure and functions.


2022 ◽  
Vol 93-94 ◽  
pp. 1-15
Author(s):  
Victoria Gritsenko

Gymnospermium odessanum is a rare relict endemic plant species. The research was carried out during G. odessanum flowering in 2019–2021 at the botanical-geographical plot “Steppes of Ukraine” of the M.M. Gryshko National Botanical Garden, National Academy of Sciences of Ukraine (NBG). Ecological and coenotic conditions of introduction at the NBG differ from natural habitats of the species and are not optimal for its vegetation. However, this species demonstrated ecological-coenotic plasticity and, over the decades, has formed a stable homeostatic introduction coenopopulation here. As of 2021, the area of introduction coenopopulation of G. odessanum at the NBG was 2,075 m2. It comprises 412 individuals of this species (including 40 seedlings, 241 juvenile, 45 immature, 40 virginal, 45 generative, and 1 sub-senile plants). Coenopopulation fragments with a high density of G. odessanum individuals are rare here, so the average density is low – only 0.2 individuals per 1 m2. In 2021, in the spectrum of age states, the total percentage of pregenerative individuals was very high and reached 88.8 %; the share of generative individuals was 10.9 %.In general, the age structure of the introduction coenopopulation of G. odessanum is characterized by long-term (2010–2021) stability. The spatial distribution of individuals in the introduction coenopopulation is of two kinds – random and in groups. This is due to combined myrmecochoric and barochoric propagation. Also due to myrmecochory, this coenopopulation tends to spread the area. Compared to natural coenopopulations, the introduction coenopopulation of G. odessanum at the NBG is characterized by a larger area, a much significant number, and, at the same time, a low average density of individuals. However, like in most of natural populations, its age spectrum is left-sided.The conducted research testifies the successful formation of the introduction coenopopulation of G. odessanum in the meadow-steppe cultural phytocoenosis of the NBG. This introduction coenopopulation is an example of a successful multi-year scientific experiment and effective ex situ protection and preservation of G. odessanum on the northern border of the Right Bank Forest-Steppe of Ukraine, far beyond the natural range of this endemic plant species.


Author(s):  
E. A. Arkhipova ◽  
A. I. Buyanovsky ◽  
D. D. Danilin ◽  
S. G. Korostelev

Data about the taxonomic composition and spatial distribution of bottom invertebrates of Kronotsky Gulf were obtained on results of bottom grab survey carried in September 2002. Analysis of the samples revealed 72 species of Polychaeta, 21 species of molluscs (Bivalvia), 17 species of crustaceans (mostly Amphipoda), 2 species of echinodermata (Echinoidea and Ophiuroidea). The average biomass in the depth range 25–200 m was 242±116 g/m2 where average density was 306±51 organisms/m2. The most high values of biomass were observed in the outlet parts of the rivers Zhupanova, Semyachik, Kronotskaya, where contribution of sea dollar Echinarachnius parma communities was principal. Despite fluctuations of the biomass of particular taxons during 50 years, the total biomass keeps stable (206–242 g/m2). Like in 1949 E. parma plays the main role in most bottom communities.


2022 ◽  
Author(s):  
Afifa Yedjour ◽  
Hanane Benmahdjoub ◽  
Abdelaali Boudjemaa

Abstract We study the diffusion of an expanding Bose-Einstein condensate released from a harmonic trap in a three-dimensional speckle disorder potential. To this end, we use the first Born approximation and examine the density profiles at short and long times. Analytical results are presented in different regimes. The spatiotemporal evolution of the density profiles is examined. We find that at long times and for a fixed disorder strength, the profile of the atomic average density decreases in power law. The time evolution of the typical size of the condensate is explored numerically.


Author(s):  
Pragya Shukla

Abstract Based on a description of an amorphous solid as a collection of coupled nanosize molecular clusters referred as basic blocks, we analyse the statistical properties of its Hamiltonian. The information is then used to derive the ensemble averaged density of the vibrational states (nonphonon) which turns out to be a Gaussian in the bulk of the spectrum and an Airy function in the low frequency regime. A comparison with experimental data for five glasses confirms validity of our theoretical predictions.


2022 ◽  
Author(s):  
Nur Arafeh-Dalmau ◽  
Adrian Munguia-Vega ◽  
Fiorenza Micheli ◽  
Ainoa Vilalta-Navas ◽  
Juan Carlos Villasenor-Derbez ◽  
...  

Climate-smart conservation addresses the vulnerability of biodiversity to climate change impacts but may require transboundary considerations. Here, we adapt and refine 16 biophysical guidelines for climate-smart marine reserves for the transboundary California Bight ecoregion. We link several climate-adaptation strategies (e.g., maintaining connectivity, representing climate refugia, and forecasting effectiveness of protection) by focusing on kelp forests and associated species. We quantify transboundary larval connectivity along ~800 km of coast and find that the number of connections and the average density of larvae dispersing through the network under future climate scenarios could decrease by ~50%, highlighting the need to protect critical steppingstone nodes. We also find that although focal species will generally recover with 30% protection, marine heatwaves could hinder subsequent recovery in the following 50 years, suggesting that protecting climate refugia and expanding the coverage of marine reserves is a priority. Together, these findings provide a first comprehensive framework for integrating climate resilience for networks of marine reserves and highlight the need for a coordinated approach in the California Bight ecoregion.


2022 ◽  
Vol 51 (6) ◽  
pp. 57-67
Author(s):  
T. V. Morokhovets ◽  
V. N. Morokhovets ◽  
S. S. Vostrikova ◽  
Z. V. Basay ◽  
N. S. Skorik ◽  
...  

The results of the study of the weed component of soybean, early grain crops and maize agrocenoses in Primorsky Territory are presented. In total, 111 species of weeds belonging to 35 families were found during the period from 2016 to 2020. Compared with the results of crop surveys conducted in 2006-2015, the total number of species detected has increased by 23. The largest number of species belongs to the families Asteraceae (24), Poaceae (15), Polygonaceae (11), Fabaceae (9), Brassicaceae (8), Caryophyllaceae (7) and Lamiaceae (5). The remaining 26 families were represented by 1-3 species each. For the first time weeds-representatives of the families Scrophulariaceae, Violaceae, Lythraceae, Onagraceae, Asclepiadaceae and Boraginaceae have been discovered. The floristic composition of soybean agrocenoses was the highest with 108 weed species from 31 families. In cereal and maize crops, weed diversity was less significant, with 75 species in 22 families and 72 species in 25 families, respectively. Weed vegetation in all the above crops is represented by 62 species of 19 families. The main weed species that grew on 97-99% of the surveyed territory with a sufficiently high average density of standing (21-61pcs/m2) were Asian copperleaf, cockspur grass and common ragweed. Also, more than half of the surveyed crops of soybeans, cereals and corn were hairy cupgrass, perennial sow thistle, common couch-grass, common lamb’s quarters, wormwood species, field horsetail, yellow thistle, dayflower and yellow foxtail. Practical measures to protect against weeds on the Primorsky Territory should be primarily aimed at controlling these species.


2022 ◽  
Vol 14 (4) ◽  
pp. 95-102
Author(s):  
A. Zh. Fursova ◽  
A. S. Derbeneva ◽  
M. S. Tarasov ◽  
M. V. Vasil’eva ◽  
J. A. Gamza ◽  
...  

The purpose of the study was to assess the changes of biomarkers of diabetic macular edema activity by optical coherence tomography angiography (OCTA) data and the relationship of these biomarkers with the response to anti-VEGF therapy during a two-year follow-up. Material and methods. The study included 59 patients (101) eyes, averagely aged 60.27 ± 9.50 years. The average number of intravitreal injections of aflibercept over the treatment period was 12.87 ± 3.50. The initial size of the foveolar avascular zone (FAZ) area — 0.37 ± 0.22 mm2 , and the acircularity index — 0.56 ± 0.14 remained unchanged after 5 months: 0.36 ± 0.24 mm2  and 0.56 ± 0.12, respectively, and being practically in the same level in 12 and 24 months. The large FAZ area, noted in the group where disorganization of retinal inner layers (DRIL) was observed (0.39 ± 0.21 mm2 ), correlated with a lower visual acuity (r = 0.67, p = 0.003). The acircularity index remained unchanged; no significant differences were found in the DRIL patient groups. After 5 loading injections, the average initial density of vessels in the macular region increased from 12.33 ± 3.86 mm to 12.75 ± 1.14 mm, after 1 year it was 13.48 ± 1.15 mm, after 2 years — 13.25 ± 3.39 mm. The average density of retinal perfusion increased at the 5th month from 29.81 ± 10.85 % to 31.55 ± 2.34 %, after 12 months to 32.91 ± 3.45, and by the end of the observation period to 31.41 ± 9.79 %. In the DRIL group, the baseline vascular density and mean perfusion volume were significantly lower: 11.17 ± 2.09 mm vs. 13.49 ± 1.14 mm and 28.40 ± 4.53 % vs. 31.20 ± 2.44 %). Conclusion. DRIL, a biomarker reflecting impaired capillary blood flow in the superficial capillary plexus and correlating with functional results, can be used as a predictor of antiangiogenic therapy effectiveness. After antiangiogenic therapy with DMO, the microcirculation indices (FAZ and acircularity) remained stable, and the vascular density and perfusion volume tended to increase, which testifies to the absence of ischemic damage.


2022 ◽  
Vol 335 ◽  
pp. 00018
Author(s):  
Edhy Sudjarwo ◽  
Muharlien Muharlien ◽  
Osfar Sjofjan ◽  
Dyah Lestari Yulianti

The aim of this study was to determine the production performance of layer hen strain Hy-Line Brown in different cage locations in closed house. The research material was 5,051 laying hens of the Hy-Line strain aged 28 weeks. House system was closed house, cage arranged to form frame A. Hy-Line Brown layer were housed at cage densities of 500 cm2 per hen. Research feed is complete feed code 324 KJ produced by PT. Charoen Pokphand Indonesia. The research method is comparative, comparing the production performance on the location of the cage in zone 1 (inlet), zone 2 (middle), and zone 3 (outlet) of a closed cage. The research sample is 10% of the total population. Observations were carried out on 6 cages which were randomly selected in each cage zone. The average density of cages is 20 birds/m2. Tabulated research data are Hen Day Production (%), egg weight (g), egg mass (kg), and feed conversion. Data analysis is analysis of variance analysis (One-Way ANOVA). Based on the results of the study, there were significant differences in the the production performance of layer hen strain Hy-Line Brown in different cage locations in closed house. The highest production performance is the cage located close to the inlet (Zone 1).


2021 ◽  
Vol 16 (3) ◽  
pp. 848-860
Author(s):  
HIRANMAY RISHI ◽  
Subrata Purkayastha

Tal and Diara regions of Malda district are extremely prone to floods, still, report higher population density than the state's average density. This indicates that the local population has learned to live with floods by developing resilience to the flood threat through better preparedness, coping, and adaptive strategies. Such micro-level strategies developed by the local people can be useful to policymakers and social scientists alike in terms of better mitigating the flood menace and associated vulnerability. This paper attempts to measure and compare the level of flood resilience of the local people living in Tal and Diara at the household level. Furthermore, the article aims to analyse whether the distance from the major flood-causing rivers, viz. Fulhar in Tal and Ganga in Diara play a role in the degree of resilience of the population to floods. The paper is empirical, where information has been collected from sample households and focus group discussion with village elders in two sets of villages, i.e., Maniknagar and Ratua in Tal and Gopalpur and Nurpur in Diara. The UNDP technique has been used to compute the composite Resilience Index (RI) consisting of Preparedness Index (PI), Immediate Coping Index (ICI), and Adaptive Index (AI). The findings suggest that the villages located in and around the levees of major flood-causing rivers, viz. Maniknagar in Tal and Gopalpur in Diara records a higher level of resilience to floods in comparison to the interior villages, viz. Ratua in Tal and Nurpur in Diara. The paper concludes that in both Tal and Diara, people have learned to cope and adapt to floods and that the closer the distance from the major flood-causing rivers, the higher the villagers' resilience to flood hazards.


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