scholarly journals Microhabitat Selection and Population Density of Nehalennia Speciosa Charpentier, 1840 (Odonata: Coenagrionidae) in a Peripheral Microrefugium

Wetlands ◽  
2021 ◽  
Vol 41 (7) ◽  
Author(s):  
Valerio Orioli ◽  
Rodolfo Gentili ◽  
Luciano Bani ◽  
Stefano Aguzzi

AbstractPeripheral populations of boreal tyrphophilic animals and plants often occupy relict Alpine peatlands, which act as microrefugia. Ecological conditions within local peatlands can lead to uncommon adaptations, highly valuable for the long-term conservation of species and habitats. The pigmy damselfly (Nehalennia speciosa) is an endangered Odonata distributed in Central and Eastern Europe with peripheral populations in the Alps. We investigated the microscale species-habitat association and the conservation status of one of these populations in a relict raised bog. We applied dynamic N-mixture models to assess population ecology and density, while disentangling predictors’ effect on ecological and observation process. We counted N. speciosa individuals in spring 2018 along with vegetation, water, soil and weather conditions during surveys. Final model resulted reliable according to performance measures. Spatial variation in N. speciosa abundance was driven by vegetation type, with a strong selection for flooded hollows where C. rostrata, R. alba and S. palustris vegetation occupy acidic and oligotrophic shallow pools. Population density showed a peak in the first decade of June and increased with accumulation of superficial water. Detection probability was generally low and decreased further when wind blew. The reduced ecological plasticity of the species imperil the species to habitat and climate changes, which will be particularly threatening for its peripheral Alpine populations in the near future, causing water imbalance and rapid vegetation turnover within the peatlands’ fragile microhabitat. The studied peat bog could thus be retained a key future microrefugium for the long-term conservation of tyrphopilous wildlife and habitats.

2019 ◽  
Vol 25 (1) ◽  
Author(s):  
Aleh Marozau ◽  
D Gordej

A long-term introduction experiment conducted in 2009–2016 revealed that in the harshest weather conditions of the northern part of Belarus associated with a difficult environmental situation on a trial area, including weakly-decomposed acid sphagnum peat and the deficiency of artificial watering, lowbush blueberry (Vaccinium angustifolium Ait.) due to the significant tolerance to abiotic factors of the environment completely fulfills its bioproductive potential. It is clear, in particular, through the formation of a continuous berry bush cover and its high resistance to cold. A sustainable cultivated phytocenosis forms. It protects a peat substrate from fires, water and wind erosions, and has a high level of positive dynamism of berry productivity during the whole period of record. It proves the appropriateness of the ecological-biological type of the species to the extreme weather and ecological conditions of the experiment. However, lowbush blueberry needs an optimization of mineral nutrition. The implementation of this condition is a guaranty of successful introduction of the plant on the cutover raised-bog peatlands in the North of Belarus.


2007 ◽  
Vol 158 (11) ◽  
pp. 349-352
Author(s):  
Grégory Amos ◽  
Ambroise Marchand ◽  
Anja Schneiter ◽  
Annina Sorg

The last Capricorns (Capra ibex ibex) in the Alps survived during the nineteenth century in the Aosta valley thanks to the royal hunting reservation (today Gran Paradiso national park). Capricorns from this reservation were successfully re-introduced in Switzerland after its Capricorn population had disappeared. Currently in Switzerland there are 13200 Capricorns. Every year 1000 are hunted in order to prevent a large variation and overaging of their population and the damage of pasture. In contrast, in the Gran Paradiso national park the game population regulates itself naturally for over eighty years. There are large fluctuations in the Capricorn population (2600–5000) which are most likely due to the climate, amount of snow, population density and to the interactions of these factors. The long-term surveys in the Gran Paradiso national park and the investigations of the capacity of this area are a valuable example for the optimal management of the ibexes in Switzerland.


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1540
Author(s):  
Bence Fülöp ◽  
Bálint Pacsai ◽  
Judit Bódis

Semi-natural grasslands were previously established through traditional land use and maintained by active management, but their extension nowadays is declining rapidly, particularly in areas that also have tourism potential. In parallel, the conservation value of the remaining areas is increasing. The shore of Lake Balaton is a particularly good example, as Lake Balaton is an area highly affected by tourism, yet there have been valuable habitats able to survive and provide refuge for many vulnerable, protected species. Fortunately, we have reliable information about the vegetation of the area from two decades ago. Comparing these data with our recent surveys we investigated the changes in habitats and the distribution of protected plant species in connection with the active conservation treatments such as grazing or cutting. Our results show that in areas where treatments are still ongoing, protected plant species are more likely to survive, or even other species can appear, which is in clear contrast with conditions experienced in abandoned areas, where at least seven protected species have disappeared. According to our results, minor, but appropriately chosen and well-executed management interventions, can help in the long-term maintenance of species-rich habitats and improving the conservation status of threatened species.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Niloufar Nouri ◽  
Naresh Devineni ◽  
Valerie Were ◽  
Reza Khanbilvardi

AbstractThe annual frequency of tornadoes during 1950–2018 across the major tornado-impacted states were examined and modeled using anthropogenic and large-scale climate covariates in a hierarchical Bayesian inference framework. Anthropogenic factors include increases in population density and better detection systems since the mid-1990s. Large-scale climate variables include El Niño Southern Oscillation (ENSO), Southern Oscillation Index (SOI), North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO), Arctic Oscillation (AO), and Atlantic Multi-decadal Oscillation (AMO). The model provides a robust way of estimating the response coefficients by considering pooling of information across groups of states that belong to Tornado Alley, Dixie Alley, and Other States, thereby reducing their uncertainty. The influence of the anthropogenic factors and the large-scale climate variables are modeled in a nested framework to unravel secular trend from cyclical variability. Population density explains the long-term trend in Dixie Alley. The step-increase induced due to the installation of the Doppler Radar systems explains the long-term trend in Tornado Alley. NAO and the interplay between NAO and ENSO explained the interannual to multi-decadal variability in Tornado Alley. PDO and AMO are also contributing to this multi-time scale variability. SOI and AO explain the cyclical variability in Dixie Alley. This improved understanding of the variability and trends in tornadoes should be of immense value to public planners, businesses, and insurance-based risk management agencies.


Mammalia ◽  
2016 ◽  
Vol 80 (4) ◽  
Author(s):  
Julia Salvador ◽  
Santiago Espinosa

AbstractOcelots were historically hunted for their skins but habitat loss is now their most serious threat, causing rapid declines in populations throughout their range. Ocelot abundance has been estimated for various locations across the Neotropics, but we still lack this information from some countries, including Ecuador. Knowing whether ocelot abundance is increasing or decreasing is important to assess the conservation status of this species and the conditions of its habitats in the Ecuadorian Amazon and in the region. To determine whether ocelot abundance and its behavior are affected by human-related activities, camera-trap surveys were carried out in two localities of Yasuní National Park (YNP), one that has experienced hunting, oil extraction, and roads (Maxus Road) and one that is largely unaffected by these activities (Lorocachi). During the survey, 35 and 36 individual ocelots were photographed in Maxus Road and Lorocachi, respectively. Population density estimates were similar for both localities, ranging from 0.31 (SE±6) to 0.85 (SE±17) ocelots/km


1986 ◽  
Vol 64 (11) ◽  
pp. 2405-2411 ◽  
Author(s):  
Charles R. Blem ◽  
Michael H. Shelor

Midwinter lipid depots of the white-throated sparrow (Zonotrichia albicollis) at Richmond, Virginia, are correlated with a suite of environmental and morphological variables. Lipid reserves allow this species to survive even the most extreme winter conditions for several hours. Variables having the greatest individual correlations with lipid reserve are average temperature of the 20 days prior to capture, fat class, body weight, and long-term (32-year) average temperature of the date of capture. A comprehensive multiple regression model based on analyses of all possible independent variables accounts for 87% of the variation in lipid reserves. The most important independent variables in this model are body weight, mean temperature of the 20 days preceding collection, fat class, extreme high temperature of the day of capture, long-term average temperature, relative humidity, chill factor, wet-bulb temperatures of the day before and the day of capture, wing length, and precipitation. The "best" equation using only measurements of environment as independent variables included time of collection in hours after sunrise and hours before sunset, Eastern Standard Time, temperature of the 20 days prior to capture, and mean wind velocity of the day before capture. Models computed solely from temperature measurements included dry-bulb temperatures of the day of capture and the day before capture, low extreme temperatures of the day of capture, wet-bulb temperatures of the day before capture, and the 20-day average dry-bulb temperature of the period prior to collection. Fattening in response to weather conditions appears to be a form of "fine-tuning" of energy reserves superimposed on a more stable, intrinsic cycle of winter fattening.


Ecosphere ◽  
2013 ◽  
Vol 4 (4) ◽  
pp. art45 ◽  
Author(s):  
M. Ballesteros ◽  
B.-J. Bårdsen ◽  
P. Fauchald ◽  
K. Langeland ◽  
A. Stien ◽  
...  

Author(s):  
Brian Miller ◽  
Hank Harlow

Our objective is to establish a long-term monitoring project that will assess the abundance and densities of selected species of mammals at sites representing five defined vegetation types found in Grand Teton National Park. The term monitoring implies data collection over multiple years. Taking long term estimations of population composition before, during, and after biotic and abiotic changes provides needed information to assess the impacts of such changes and furnish useful options for management decisions. This standardized monitoring plan will provide information on small and medium-sized mammals that will (1) assess species use of habitat, (2) monitor changes in species composition as a result of environmental change, such as precipitation and temperature, (3) produce predictive models of small and medium-sized mammal distribution based on vegetation type, and (4) analyze the impact of wolf colonization on the mammal (and plant) community.


2020 ◽  
Vol 2 (4) ◽  
Author(s):  
Safriwan Safriwan ◽  
Idris Idris

Abstract : The study describes the effects on globalization population density andeconomic growth on environmental degradation in Indonesia. This research uses a timeseries data from year 1971 - 2017, with method Error Correction Model (ECM). Datasources from Global Carbon Project, KOF Swiss Economic Institute, and WorldBank. Research result explain that (1) Globalization in long term has a insignificantpositive effect on environmental degradation in Indonesia, but short term globalizationhas a insignificant negative effect on environmental degradation in Indonesia (2)Population density in long term has a significant positive , and short term has ainsignificant positive effect on environmental degradation in Indonesia (3) Economicgrowth in long and short term has a significant positive effect on environmentaldegradation in Indonesia.Keywords : Environmental Degradation, Globalization Population Density AndEconomic Growth.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zbigniew Zając ◽  
Joanna Kulisz ◽  
Aneta Woźniak ◽  
Katarzyna Bartosik ◽  
Adil Khan

AbstractDermacentor reticulatus ticks are one of the most important vectors and reservoirs of tick-borne pathogens in Europe. Changes in the abundance and range of this species have been observed in the last decade and these ticks are collected in areas previously considered tick-free. This may be influenced by progressive climate change. Eastern Poland is an area where the local population of D. reticulatus is one of the most numerous among those described so far. At the same time, the region is characterized by a significant increase in the mean air temperature in recent years (by 1.81 °C in 2020) and a decrease in the average number of days with snow cover (by 64 days in 2020) and in the number of days with frost (by 20 days in 2020) on an annual basis compared to the long-term average. The aim of our research was to investigate the rhythms of seasonal activity and the population size of D. reticulatus in the era of progressive climate change. To this end, questing ticks were collected in 2017–2020. Next, the weather conditions in the years of observation were analyzed and compared with multi-year data covering 30 years preceding the study. The research results show that, in eastern Poland, there is a stable population of D. reticulatus with the peak of activity in spring or autumn (up to a maximum of 359 individuals within 30 min of collection) depending on the year of observation. Ticks of this species may also be active in winter months. The activity of D. reticulatus is influenced by a saturation deficit.


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