Search results for: species distribution modelling
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9242

Search results for: species distribution modelling

9182 Modelling a Distribution Network with a Hybrid Solar-Hydro Power Plant in Rural Cameroon

Authors: Contimi Kenfack Mouafo, Sebastian Klick

Abstract:

In the rural and remote areas of Cameroon, access to electricity is very limited since most of the population is not connected to the main utility grid. Throughout the country, efforts are underway to not only expand the utility grid to these regions but also to provide reliable off-grid access to electricity. The Cameroonian company Solahydrowatt is currently working on the design and planning of one of the first hybrid solar-hydropower plants of Cameroon in Fotetsa, in the western region of the country, to provide the population with reliable access to electricity. This paper models and proposes a design for the low-voltage network with a hybrid solar-hydropower plant in Fotetsa. The modelling takes into consideration the voltage compliance of the distribution network, the maximum load of operating equipment, and most importantly, the ability for the network to operate as an off-grid system. The resulting modelled distribution network does not only comply with the Cameroonian voltage deviation standard, but it is also capable of being operated as a stand-alone network independent of the main utility grid.

Keywords: Cameroon, rural electrification, hybrid solar-hydro, off-grid electricity supply, network simulation

Procedia PDF Downloads 108
9181 Distribution of Malaria-Infected Anopheles Mosquitoes in Kudat, Ranau and Tenom of Sabah, Malaysia

Authors: Ahmad Fakhriy Hassan, Rohani Ahmad, Zurainee Mohamed Nor, Wan Najdah Wan Mohamad Ali

Abstract:

In Malaysia, it was realized that while the incidence of human malaria is decreasing, the incidence of Plasmodium knowlesi malaria appears to be on the rise, especially in rural areas of Sabah, East Malaysia. The primary vector for P. knowlesi malaria in Sabah is An. balabacensis a species found abundant in rural areas, shown to rest and feed outdoor throughout the night, which makes its control very challenging. This study aims to examine the distribution of malaria-infected Anopheles mosquitoes in three areas in Sabah, namely Kudat, Ranau, and Tenom, known as areas in Sabah that presented high number of malaria cases. Briefly, mosquitoes were caught every 6 weeks for the period of 18 months using Human Landing Catching (HLC) technique from May 2016 to November 2017. Identification of species was done using microscopy and molecular methods. Molecular method is also used to detect malaria parasite in all mosquito collected. An. balabacensis was present in all the study areas. In Kudat, six other Anopheles species were also detected, namely, An. barumbrosus, An. latens, An. letifer, An. maculatus, An. sundaicus and An. tesselatus. In Ranau five other Anopheles species were detected, namely, An. barumbrosus, An. donaldi., An. hodgkini, An. maculatus, and An. tesselatus while in Tenom seven more species An. donaldi, An. umbrosus, An. barumbrosus, An.latens, An. hodgkini, An. maculatus, and An. tesselatus were detected. This study showed 24% out of 259, 39% out of 127, and 26% out of 265 Anopheles mosquito collected in Kudat, Ranau, and Tenom were detected positive for malaria parasite respectively. In Kudat An. balabacensis, An. barumbrosus, An. latens, An. maculatus, An. sundaicus and An. tesselatus were the six out of eight Anopheles species that were found infected with malaria parasite. All Anopheles species collected in Ranau were positive for malaria while In Tenom, only five out of eight species; An. balabacensus, An. donaldi, An. hodgkini, An. maculatus, and An. latens were detected positive for malaria parasite. Interestingly, for all study areas An. balabacensis was shown to be the only species infected with four malaria species; P. falciparum, P. knowlesi, P. vivax, and Plasmodium sp. This finding clearly indicates that An. balabacensis is the dominant malaria vector in Kudat, Ranau, and Tenom.

Keywords: Anopheles balabacensis, human landing catching technique, nested PCR, Plasmodium knowlesi, Simian malaria

Procedia PDF Downloads 123
9180 Assessing Climate-Induced Species Range Shifts and Their Impacts on the Protected Seascape on Canada’s East Coast Using Species Distribution Models and Future Projections

Authors: Amy L. Irvine, Gabriel Reygondeau, Derek P. Tittensor

Abstract:

Marine protected areas (MPAs) within Canada’s exclusive economic zone help ensure the conservation and sustainability of marine ecosystems and the continued provision of ecosystem services to society (e.g., food, carbon sequestration). With ongoing and accelerating climate change, however, MPAs may become undermined in terms of their effectiveness at fulfilling these outcomes. Many populations of species, especially those at their thermal range limits, may shift to cooler waters or become extirpated due to climate change, resulting in new species compositions and ecological interactions within static MPA boundaries. While Canadian MPA management follows international guidelines for marine conservation, no consistent approach exists for adapting MPA networks to climate change and the resulting altered ecosystem conditions. To fill this gap, projected climate-driven shifts in species distributions on Canada’s east coast were analyzed to identify when native species emigrate and novel species immigrate within the network and how high mitigation and carbon emission scenarios influence these timelines. Indicators of the ecological changes caused by these species' shifts in the biological community were also developed. Overall, our research provides projections of climate change impacts and helps to guide adaptive management responses within the Canadian east coast MPA network.

Keywords: climate change, ecosystem modeling, marine protected areas, management

Procedia PDF Downloads 69
9179 Impact of Land-Use and Climate Change on the Population Structure and Distribution Range of the Rare and Endangered Dracaena ombet and Dobera glabra in Northern Ethiopia

Authors: Emiru Birhane, Tesfay Gidey, Haftu Abrha, Abrha Brhan, Amanuel Zenebe, Girmay Gebresamuel, Florent Noulèkoun

Abstract:

Dracaena ombet and Dobera glabra are two of the most rare and endangered tree species in dryland areas. Unfortunately, their sustainability is being compromised by different anthropogenic and natural factors. However, the impacts of ongoing land use and climate change on the population structure and distribution of the species are less explored. This study was carried out in the grazing lands and hillside areas of the Desa'a dry Afromontane forest, northern Ethiopia, to characterize the population structure of the species and predict the impact of climate change on their potential distributions. In each land-use type, abundance, diameter at breast height, and height of the trees were collected using 70 sampling plots distributed over seven transects spaced one km apart. The geographic coordinates of each individual tree were also recorded. The results showed that the species populations were characterized by low abundance and unstable population structure. The latter was evinced by a lack of seedlings and mature trees. The study also revealed that the total abundance and dendrometric traits of the trees were significantly different between the two land uses. The hillside areas had a denser abundance of bigger and taller trees than the grazing lands. Climate change predictions using the MaxEnt model highlighted that future temperature increases coupled with reduced precipitation would lead to significant reductions in the suitable habitats of the species in northern Ethiopia. The species' suitable habitats were predicted to decline by 48–83% for D. ombet and 35–87% for D. glabra. Hence, to sustain the species populations, different strategies should be adopted, namely the introduction of alternative livelihoods (e.g., gathering NTFP) to reduce the overexploitation of the species for subsistence income and the protection of the current habitats that will remain suitable in the future using community-based exclosures. Additionally, the preservation of the species' seeds in gene banks is crucial to ensure their long-term conservation.

Keywords: grazing lands, hillside areas, land-use change, MaxEnt, range limitation, rare and endangered tree species

Procedia PDF Downloads 61
9178 Sympatric Calanus Species: A High Temporal Resolution of Reproductive Timing and Stage Composition

Authors: Mads Schultz, Galice Hoarau, Marvin Choquet

Abstract:

Members of the genus Calanus are key species in the North Atlantic and Arctic marine ecosystems due to their vast abundance and their ability to accumulate high amounts of lipid. As a link between primary producers and higher trophic levels, the temporal presence of each Calanus species is important in a time of changing communities and northward distribution shifts. This study focused on the temporal niches of the sympatric species Calanus helgolandicus, Calanus finmarchicus, Calanus glacialis, and Calanus hyperboreus in Skjerstad fjord, a Norwegian fjord (67˚14’N, 14 ˚44’E). Three depth intervals were sampled monthly over a year, targeting copepodite stages of the genus Calanus. Species determination was carried out genetically using insertion/deletion markers. In addition, during the reproductive season (Jan-May), weekly samples of the upper 50 meters of the water column targeting nauplii and 5 depth intervals targeting copepodites were collected. Nauplii samples were sorted into two groups (NI-NIII and NIV-NVI), and species were genetically identified. Specimens from stage CIV to adults from each depth interval of copepodite sampling were photographed in order to generate a supporting timeline of visual traits, including gonad maturation stage, presence of stomach content, and total lipid content. The most abundant species were Calanus finmarchicus and Calanus glacialis, followed by Calanus hyperboreus. These species were present in the water column throughout the year, whereas Calanus helgolandicus, the least abundant species, was only present during the summer and autumn period. Each species showed distinct temporal niches, with Calanus finmarchicus occupying the upper 50 meters longer than any of the other species. Calanus hyperboreus dominates in abundance early in the spring but are outnumbered by Calanus glacialis and Calanus finmarchicus after spring bloom sets in. In Skjerstad fjord, Calanus hyperboreus is a clear capital breeder with a long period of nauplii presence before the spring bloom. Calanus glacialis and Calanus finmarchicus both utilize income breeding, with Calanus glacialis developing to the larger nauplii stages quicker than Calanus finmarchicus, but also having a shorter reproduction period. Indeed, the “traditional Arctic” species Calanus hyperboreus and Calanus glacialis appear to end their reproduction period earlier than the North Atlantic Calanus finmarchicus.

Keywords: calanus, depth distribution, reproduction, stage composition, temporal niches

Procedia PDF Downloads 133
9177 Species Diversity of Some Remarkable New Records of Lichens from Chwarta District, Kurdistan Region of Iraq

Authors: Salah Abdulla Salih, Muhamad Sohrabi

Abstract:

This paper aims to study the species, morphology, habitats and geographical distribution of new records of lichens from the Chwarta districts Kurdistan Region of Iraq from September 2022 to June 2023. As a result of the survey in the different locations belonging to the district, found that there are eleven species of lichens are reported from Iraq for the first time. Of these, the taxa of Lecanora thallophila H. Magn is the first species of parasitic lichen reported from Iraq, including the newly recorded genus of lichen Acarospora A.Massal. The lichenized fungi are Acarospora bullata Anzi., Acarospora laqueata Stizenb., Acarospora umbilicata Bagl., Acrocordia gemmata (Ach.) A. Massal., Squamulea subsoluta (Nyl.) Arup, Søchting & Frödén., Coppinsiella ulcerosa (Coppins & P.James) S.Y.Kondr. & L.Lőkös., Myriolecis flowersiana (H. Magn.) Śliwa, Zhao Xin & Lumbsch., Megaspora rimisorediata Valadbeigi & A. Nordin sp. nov., Physcia subtilis Degel., Polycauliona polycarpa (Hoffm.) Frödén, Arup, & Søchting.

Keywords: apothecia, lichen species, new records, Kurdistan region

Procedia PDF Downloads 51
9176 Environmental Controls on the Distribution of Intertidal Foraminifers in Sabkha Al-Kharrar, Saudi Arabia: Implications for Sea-Level Changes

Authors: Talha A. Al-Dubai, Rashad A. Bantan, Ramadan H. Abu-Zied, Brian G. Jones, Aaid G. Al-Zubieri

Abstract:

Contemporary foraminiferal samples sediments were collected from the intertidal sabkha of Al-Kharrar Lagoon, Saudi Arabia, to study the vertical distribution of Foraminifera and, based on a modern training set, their potential to develop a predictor of former sea-level changes in the area. Based on hierarchical cluster analysis, the intertidal sabkha is divided into three vertical zones (A, B & C) represented by three foraminiferal assemblages, where agglutinated species occupied Zone A and calcareous species occupied the other two zones. In Zone A (high intertidal), Agglutinella compressa, Clavulina angularis and C. multicamerata are dominant species with a minor presence of Peneroplis planatus, Coscinospira hemprichii, Sorites orbiculus, Quinqueloculina lamarckiana, Q. seminula, Ammonia convexa and A. tepida. In contrast, in Zone B (middle intertidal) the most abundant species are P. planatus, C. hemprichii, S. orbiculus, Q. lamarckiana, Q. seminula and Q. laevigata, while Zone C (low intertidal) is characterised by C. hemprichii, Q. costata, S. orbiculus, P. planatus, A. convexa, A. tepida, Spiroloculina communis and S. costigera. A transfer function for sea-level reconstruction was developed using a modern dataset of 75 contemporary sediment samples and 99 species collected from several transects across the sabkha. The model provided an error of 0.12m, suggesting that intertidal foraminifers are able to predict the past sea-level changes with high precision in Al-Kharrar Lagoon, and thus the future prediction of those changes in the area.

Keywords: Lagoonal foraminifers, intertidal sabkha, vertical zonation, transfer function, sea level

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9175 Atlantic Sailfish (Istiophorus albicans) Distribution off the East Coast of Florida from 2003 to 2018 in Response to Sea Surface Temperature

Authors: Meredith M. Pratt

Abstract:

The Atlantic sailfish (Istiophorus albicans) ranges from 40°N to 40°S in the Western Atlantic Ocean and has great economic and recreational value for sport fishers. Off the eastern coast of Florida, charter boats often target this species. Stuart, Florida, bills itself as the sailfish capital of the world. Sailfish tag data from The Billfish Foundation and NOAA was used to determine the relationship between sea surface temperature (SST) and the distribution of Atlantic sailfish caught and released over a fifteen-year period (2003 to 2018). Tagging information was collected from local sports fishermen in Florida. Using the time and location of each landed sailfish, a satellite-derived SST value was obtained for each point. The purpose of this study was to determine if sea surface warming was associated with changes in sailfish distribution. On average, sailfish were caught at 26.16 ± 1.70°C (x̄ ± s.d.) over the fifteen-year period. The most sailfish catches occurred at temperatures ranging from 25.2°C to 25.5°C. Over the fifteen-year period, sailfish catches decreased at lower temperatures (~23°C and ~24°C) and at 31°C. At ~25°C and ~30°C there was no change in catch numbers of sailfish. From 26°C to 29°C, there was an increase in the number of sailfish. Based on these results, increasing ocean temperatures will have an impact on the distribution and habitat utilization of sailfish. Warming sea surface temperatures create a need for more policy and regulation to protect the Atlantic sailfish and related highly migratory billfish species.

Keywords: atlantic sailfish, Billfish, istiophorus albicans, sea surface temperature

Procedia PDF Downloads 118
9174 Intertidal Fixed Stake Net Trap (Hadrah) Fishery in Kuwait, Distribution, Catch Rate, and Species Composition

Authors: Ali F. Al-Baz, Mohsen M. Al-Husaini, James M. Bishop

Abstract:

Intertidal fixed stake net trap (hadrah) is one of the oldest fishing gears used throughout the Arabian Gulf countries since 1800s and also one of most efficient methods of capturing fish from the intertidal area. This study described the hadrah fishery in Kuwait. From October 2001 to December 2002, more than 37,372 specimens representing 95 species (89 fish, 2 mollusks, 4 crustaceans) were measured from hadrah located in three different areas along Kuwait's coast. In Kuwait Bay, catch rates averaged 62 kg/sir day (range 14 kg/sir-day in February to 160 kg/sir-day in October 2002). Commercial species accounted for 41% of the catches. Catches from Failakah Island averaged 96 kg/sir-day from June through September, with 61% of the catch being commercial species. In the southern area, catches averaged only 32 kg/sir-day, and only 34% were commercially important. Forty percent of the hadrah catches were juveniles which shows that the shallow intertidal waters are prime nursery habitat, particularly in Kuwait Bay. To maintain ecosystem biodiversity and recruitment success of the fishes, we recommended that all hadrah should be removed from Kuwait Bay. In the future, removal of hadrah in other locations should be considered.

Keywords: catch and effort, hadrah, intertidal fixed stake net, Kuwait, species composition

Procedia PDF Downloads 484
9173 A Proposed Mechanism for Skewing Symmetric Distributions

Authors: M. T. Alodat

Abstract:

In this paper, we propose a mechanism for skewing any symmetric distribution. The new distribution is called the deflation-inflation distribution (DID). We discuss some statistical properties of the DID such moments, stochastic representation, log-concavity. Also we fit the distribution to real data and we compare it to normal distribution and Azzlaini's skew normal distribution. Numerical results show that the DID fits the the tree ring data better than the other two distributions.

Keywords: normal distribution, moments, Fisher information, symmetric distributions

Procedia PDF Downloads 639
9172 Extreme Value Modelling of Ghana Stock Exchange Indices

Authors: Kwabena Asare, Ezekiel N. N. Nortey, Felix O. Mettle

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Modelling of extreme events has always been of interest in fields such as hydrology and meteorology. However, after the recent global financial crises, appropriate models for modelling of such rare events leading to these crises have become quite essential in the finance and risk management fields. This paper models the extreme values of the Ghana Stock Exchange All-Shares indices (2000-2010) by applying the Extreme Value Theory to fit a model to the tails of the daily stock returns data. A conditional approach of the EVT was preferred and hence an ARMA-GARCH model was fitted to the data to correct for the effects of autocorrelation and conditional heteroscedastic terms present in the returns series, before EVT method was applied. The Peak Over Threshold (POT) approach of the EVT, which fits a Generalized Pareto Distribution (GPD) model to excesses above a certain selected threshold, was employed. Maximum likelihood estimates of the model parameters were obtained and the model’s goodness of fit was assessed graphically using Q-Q, P-P and density plots. The findings indicate that the GPD provides an adequate fit to the data of excesses. The size of the extreme daily Ghanaian stock market movements were then computed using the Value at Risk (VaR) and Expected Shortfall (ES) risk measures at some high quantiles, based on the fitted GPD model.

Keywords: extreme value theory, expected shortfall, generalized pareto distribution, peak over threshold, value at risk

Procedia PDF Downloads 522
9171 Analysis and Study of Phytoplankton and the Environmental Characteristics of Tarkwa Bay, Lagos, South-Western, Nigeria

Authors: Bukola Dawodu, Charles Onyema

Abstract:

The phytoplankton and environmental characteristics of Tarkwa Bay, Lagos in South-western Nigeria were investigated from January to June 2012. Environmental characteristics within the Bay were largely determined by floodwater inflow in the wet months (April – June) and increased tidal marine conditions in the dry months (January – March). Similarly, rainfall distribution and possibly tidal seawater inflow were the key factors that govern the variation in phytoplankton distribution, species diversity, chlorophyll a concentration and environmental characteristics of the bay. Values for physico-chemical parameters were indicative of high levels of fluctuations inwards from the East mole towards Tarkwa Bay (e.g. T.S.S > 11mg/L, T.D.S > 33541.0mg/L, D.O. < 5.4). Chlorophyll A values did not show any discernable pattern and correlated negatively with total dissolved solids and total suspended solids (r = -0.27 and -0.04) as both were inconsistent throughout the study period. Four phytoplankton divisions were observed throughout the sampling period with the Bacillariophyta (diatoms) being the dominant group followed by Dinophyta (dinoflagellates), Cyanophyta (the blue-green algae) and Chlorophyta (the green algae). A total of twenty-one species from nine genera were recorded during the period of study. Diatoms formed the most abundant group making fifteen species from five genera. The centric forms dominated over the pennates in the diatom group with Skeletonema sp. Chaetoceros spp. and Coscinodiscus spp. being the dominant centric diatoms while Navicula spp. was the more dominant pennate form. The Dinoflagellates were represented by six species from one genus, the blue-green algae with five species from two genera while the green algae had one species from one genus. Comparatively, total biomass was more in the dry months (Jan. - Mar.) and decreased in the 'wet months' (Apr. – Jun.). Species diversity (S), Shannon Wiener index (Hs), Margalef Index (d) and Equitability Index (j) values were higher during the dry months while reduced value marked the wet months possibly as a result of dilution of rain effects. Outcomes of bio-indices variations were reflections of the degree of occurrence and abundance of species linked to seasons operating in the study site.

Keywords: coastal waters, phytoplankton, species abundance, ecosystems

Procedia PDF Downloads 162
9170 Palyno-Morphological Characteristics of Gymnosperm Flora of Pakistan and Its Taxonomic Implications with Light Microscope and Scanning Electron Microscopy Methods

Authors: Raees Khan, Sheikh Z. Ul Abidin, Abdul S. Mumtaz, Jie Liu

Abstract:

The present study is intended to assess gymnosperms pollen flora of Pakistan using Light Microscope (LM) and Scanning Electron Microscopy (SEM) for its taxonomic significance in identification of gymnosperms. Pollens of 35 gymnosperm species (12 genera and five families) were collected from its various distributional sites of gymnosperms in Pakistan. LM and SEM were used to investigate different palyno-morphological characteristics. Five pollen types (i.e., Inaperturate, Monolete, Monoporate, Vesiculate-bisaccate, and Polyplicate) were observed. In equatorial view seven types of pollens were observed, in which ten species were sub-angular, nine species were triangular, six species were perprolate, three species were rhomboidal, three species were semi-angular, two species were rectangular and two species were prolate. While five types of pollen were observed in polar view, in which ten species were spheroidal, nine species were angular, eight were interlobate, six species were circular, and two species were elliptic. Eighteen species have rugulate and 17 species has faveolate ornamentation. Eighteen species have verrucate and 17 have gemmate type sculpturing. The data was analysed through cluster analysis. The study showed that these palyno-morphological features have significance value in classification and identification of gymnosperms. Based on these different palyno-morphological features, a taxonomic key was proposed for the accurate and fast identifications of gymnosperms from Pakistan.

Keywords: gymnosperms, palynology, Pakistan, taxonomy

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9169 Devising a Paradigm for the Assessment of Guilt across Species

Authors: Trisha S. Malhotra

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While there exist frameworks to study the induction, manifestation, duration and general nature of emotions like shame, guilt, embarrassment and pride in humans, the same cannot be said for other species. This is because such 'complex' emotions have situational inductions and manifestations that supposedly vary due to differences between and within different species' ethology. This paper looks at the socio-adaptive functions of guilt to posit why this emotion might be observed across varying species. Primarily, the experimental paradigm of guilt-assessment in domesticated dogs is critiqued for lack of ethological consideration in its measurement and analysis. It is argued that a paradigm for guilt-assessment should measure the species-specific prosocial approach behavior instead of the immediate feedback of the 'guilty'. Finally, it is asserted that the origin of guilt is subjective and if it must be studied across a plethora of species, its definition must be tailored to fit accordingly.

Keywords: guilt, assessment, dogs, prosocial approach behavior, empathy, species, ethology

Procedia PDF Downloads 287
9168 Diversity of Bird Species and Conservation of Two Lacustrine Wetlands of the Upper Benue Basin, Adamawa, Nigeria

Authors: D. l. David, J. A. Wahedi, U. Buba, R. Zakariya

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Between January, 2004 to December, 2005, studies were carried out on the bird species diversity and relative abundance of two lakes, Kiri and Gyawana near Numan using the “Timed Species Count (TSC)” method. 163 species in 53 bird families and 160 species in 55 bird families were recorded at Kiri and Gyawana lakes respectively. There was no significant difference in species diversity within bird families between the two lakes (p > 0.05), whereas in Gyawana Lake, one of the sites qualified as Ramsar site, none strongly qualified as an Important Bird Area (IBA). The significance of these findingsare also discussed.

Keywords: conservation, diversity, lacustrine, wetlands

Procedia PDF Downloads 656
9167 Artemisia Species from Iran as Valuable Resources for Medicinal Uses

Authors: Mohammad Reza Naghavi, Farzad Alaeimoghadam, Hossein Ghafoori

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Artemisia species, which are medically beneficial, are widespread in temperate regions of both Northern and Southern hemispheres among which Iran is located. About 35 species of Artemisia are indigenous in Iran among them some are widespread in all or most provinces, yet some are restricted to some specific regions. In this review paper, initially, GC-Mass results of some experiments done in different provinces of Iran are mentioned among them some compounds are common among species, some others are mostly restricted to other species; after that, medical advantages based on some researches on species of this genus are reviewed; different qualities such as anti-leishmania, anti-bacteria, antiviral as well as anti-proliferative could be mentioned.

Keywords: artemisia, GC-Mass analysis, medical advantage, antiviral

Procedia PDF Downloads 520
9166 Modelling the Dynamics of Corporate Bonds Spreads with Asymmetric GARCH Models

Authors: Sélima Baccar, Ephraim Clark

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This paper can be considered as a new perspective to analyse credit spreads. A comprehensive empirical analysis of conditional variance of credit spreads indices is performed using various GARCH models. Based on a comparison between traditional and asymmetric GARCH models with alternative functional forms of the conditional density, we intend to identify what macroeconomic and financial factors have driven daily changes in the US Dollar credit spreads in the period from January 2011 through January 2013. The results provide a strong interdependence between credit spreads and the explanatory factors related to the conditions of interest rates, the state of the stock market, the bond market liquidity and the exchange risk. The empirical findings support the use of asymmetric GARCH models. The AGARCH and GJR models outperform the traditional GARCH in credit spreads modelling. We show, also, that the leptokurtic Student-t assumption is better than the Gaussian distribution and improves the quality of the estimates, whatever the rating or maturity.

Keywords: corporate bonds, default risk, credit spreads, asymmetric garch models, student-t distribution

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9165 Ecological Study of Habitat Conditions and Distribution of Cistanche tubulosa (Rare Plant Species) in Pakpattan District, Pakistan

Authors: Shumaila Shakoor

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C. tubulosa is a rare parasitic plant. It is found to be endangered and it acquires nutrition by penetrating roots deep in host roots. It has momentous potential to fulfill local and national health needs. This specie became endangered due to its parasitic mode of life and lack of awareness. Investigation of distribution and habitat conditions of C. tubulosa from District Pakpattan is the objective of this study. To explore its habitat conditions and community ecology phytosociological survey of C. tubulosa in different habitats i.e roadsides and graveyards was carried out. It was found that C. tubulosa occurs successfully in different habitats like graveyards and roadsides with specific neighboring species. Soil analysis was carried out by taking soil samples from seven sites. Soil was analyzed for pH, EC, soil texture, OM, N %age, Ca, Mg, P and K, which shows that soil of C. tubulosa is rich in all these nutrients.

Keywords: organic matter, potassium, phosphorus, magnesium

Procedia PDF Downloads 175
9164 Valuing Non-Market Environmental Benefits of the Biodiversity Conservation Project

Authors: Huynh Viet Khai, Mitsuyasu Yabe

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The study investigated the economic value of biodiversity attributes that could provide policy-makers reliable information to estimate welfare losses due to biodiversity reductions and analyse the trade-off between biodiversity and economics. In order to obtain the non-market benefits of biodiversity conservation, an indirect utility function and willingness to pay for biodiversity attributes were applied using the approach of choice modelling with the analysis of conditional logit model. The study found that Mekong Delta residents accepted their willingness to pay for VND 913 monthly for a one percent increase in healthy vegetation, VND 360 for an additional mammal species and VND 2,440 to avoid the welfare losses of 100 local farmers.

Keywords: choice modelling, genetic resources, wetland conservation, marginal willingness to pay

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9163 Modelling Railway Noise Over Large Areas, Assisted by GIS

Authors: Conrad Weber

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The modelling of railway noise over large projects areas can be very time consuming in terms of preparing the noise models and calculation time. An open-source GIS program has been utilised to assist with the modelling of operational noise levels for 675km of railway corridor. A range of GIS algorithms were utilised to break up the noise model area into manageable calculation sizes. GIS was utilised to prepare and filter a range of noise modelling inputs, including building files, land uses and ground terrain. A spreadsheet was utilised to manage the accuracy of key input parameters, including train speeds, train types, curve corrections, bridge corrections and engine notch settings. GIS was utilised to present the final noise modelling results. This paper explains the noise modelling process and how the spreadsheet and GIS were utilised to accurately model this massive project efficiently.

Keywords: noise, modeling, GIS, rail

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9162 Flora of Seaweeds and the Preliminary Screening of the Fungal Endophytes

Authors: Nur Farah Ain Zainee, Ahmad Ismail, Nazlina Ibrahim, Asmida Ismail

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Seaweeds are economically important as they have the potential of being utilized, the capabilities and opportunities for further expansion as well as the availability of other species for future development. Hence, research on the diversity and distribution of seaweeds have to be expanded whilst the seaweeds are one of the Malaysian marine valuable heritage. The study on the distribution of seaweeds at Pengerang, Johor was carried out between February and November 2015 at Kampung Jawa Darat and Kampung Sungai Buntu. The study sites are located at the south-southeast of Peninsular Malaysia where the Petronas Refinery and Petrochemicals Integrated Project Development (RAPID) are in progress. In future, the richness of seaweeds in Pengerang will vanish soon due to the loss of habitat prior to RAPID project. The research was completed to study the diversity of seaweed and to determine the present of fungal endophyte isolated from the seaweed. The sample was calculated by using quadrat with 25-meter line transect by 3 replication for each site. The specimen were preserved, identified, processed in the laboratory and kept as herbarium specimen in Algae Herbarium, Universiti Kebangsaan Malaysia. The complete thallus specimens for fungal endophyte screening were chosen meticulously, transferred into sterile zip-lock plastic bag and kept in the freezer for further process. A total of 29 species has been identified including 12 species of Chlorophyta, 2 species of Phaeophyta and 14 species of Rhodophyta. From February to November 2015, the number of species highly varied and there was a significant change in community structure of seaweeds. Kampung Sungai Buntu shows the highest diversity throughout the study compared to Kampung Jawa Darat. This evidence can be related to the high habitat preference such as types of shores which is rocky, sandy and having lagoon and bay. These can enhance the existence of the seaweeds community due to variations of the habitat. Eighteen seaweed species were selected and screened for the capability presence of fungal endophyte; Sargassum polycystum marked having the highest number of fungal endophyte compared to the other species. These evidence has proved the seaweed have capable of accommodating a lot of species of fungal endophytes. Thus, these evidence leads to positive consequences where further research should be employed.

Keywords: diversity, fungal endophyte, macroalgae, screening, seaweed

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9161 The Nubian Ibex’s Distribution, Population, Habitat, and Conservation Status in Sudan’s Red Sea State Over the Past Decade

Authors: Lubna M. A. Hassan, Nasir Brema, Abdallah Mamy, Insaf Yahya, Tanzil A. G., Ahmed M. M. Hasoba, Omer A. Suliman

Abstract:

The Nubian ibex species has been categorized as vulnerable by the International Union for Conservation of Nature (IUCN) due to a lack of population data in specific regions within their habitat. This species faces numerous challenges, including habitat loss caused by agricultural practices, livestock rearing, mining activity, and infrastructure development. Additionally, competition with non-native species and hunting pose significant threats to their survival. Unfortunately, studies on the distribution, conservation status, ecology, and health of the ibex are limited and primarily descriptive in nature. In order to bridge this knowledge gap, recent surveys were conducted in the Red Sea State of Sudan during specific periods in 2015, 2016, 2019, and 2021. These surveys have provided valuable insights into the distribution, habitats, and conservation status of the Nubian ibex in the Red Sea State. The findings indicate that the Capra nubiana ibex can be found across more than 17 mountains in the Red Sea State. However, the total population estimate from recent years suggests that there are fewer than 250 individuals remaining. The study has also identified the highest altitude at which the Nubian ibex habitats existed in Sudan's Red Sea State, measuring 1675 m. This area harbors a diverse array of Nubian ibex habitats, encompassing a total of 21 wild plant species from 10 distinct families. The region experiences an average annual temperature ranging from 20.64°C in January to 33.30°C in August. Precipitation occurs in November and December, although it is characterized by unreliability and erratic patterns. It is important to note that these population estimates were obtained through surveys conducted in collaboration with rangers and local communities, and adjustments to survey methods are necessary to accommodate the challenging mountainous terrain, such as utilizing aerial surveys. To effectively address these threats, it is imperative to establish comprehensive long-term monitoring programs.

Keywords: Nubian ibex, distribution, population, habitats

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9160 Distribution and Population Status of Canis spp. Threats and Conservation in Lehri Nature Park, Salt Range, District Jhelum

Authors: Muhammad Saad, AzherBaig, Anwar Maqsood, Muhammad Waseem

Abstract:

The grey wolf has been ranked endangered and Asiatic jackal as near threatened in Pakistan. Scientific data on population and threats to these species are not available in Pakistan, which is required for their proper management and conservation. The present study was conducted to collect data on distribution range, population status and threats to both of these Canis species in Lehri Nature Park. The data were collected using direct observations and indirect signs in the field. The population of grey wolf and Asiatic jackal were scattered into pocket of the study area and its surroundings. The current population of grey wolf was estimated 06 individuals and that of Asiatic jackal 28 individuals in the study area. The present study showed that grey wolf and Asiatic jackal were distributed in the northern and southern part of the study area having dense vegetation cover of tress and shrub between the altitudes of 330 m and 515 m. The research finding revealed that the scrub forest is the most preferred habitat of both the species but due to anthropogenic pressure the scrub forest is under severe threat. The dominant trees species were Acacia modesta, Zizyphus nummularia, and Prosopis juliflora and shrubs species of Dodonea-viscosa, Calotropis procera and Adhatoda vasica. Urial is one of the natural prey species: their population is low due to a number of reasons and therefore the maximum dependence of the wolves was on the livestock of the local and nomadic shepherds. The main prey species in the livestock was goats and sheep. The interviews were conducted with the eye witnesses of wolf attacks including livestock being killed by 5-6 numbers of wolves in different hamlets in the study area. The killing rate of the livestock by the wolves was greater when the nomadic shepherds were present in the area and decreased when they left the area. Presence of nomadic shepherds and killing rate has relation with the shifting of the wolves from the study area. It is further concluded that the population of the grey wolf and Asiatic jackal has decreased over time due to less availability of the natural prey species and habitat destruction.

Keywords: wildlife ecology, population conservation, rehabilitation, conservation

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9159 Distribution of Epiphytic Lichen Biodiversity and Comparision with Their Preferred Tree Species around the Şeker Canyon, Karabük, Turkey

Authors: Hatice Esra Akgül, Celaleddin Öztürk

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Lichen biodiversity in forests is controlled by environmental conditions. Epiphytic lichens have some degree of substrate specificity. Diversity and distribution of epiphytic lichens are affected by humidity, light, altitude, temperature, bark pH of the trees.This study describes the epiphytic lichen communities with comparing their preferred tree species. 34 epiphytic lichen taxa are reported on Pinus sp. L., Quercus sp. L., Fagus sp. L., Carpinus sp. L., Abies sp. Mill., Fraxinus sp. Tourn. ex L. from different altitudes around the Şeker Canyon (Karabük, Turkey). 11 of these taxa are growing on Quercus sp., 10 of them are growing on Fagus sp., 7 of them are growing on Pinus sp., 4 of them are on Carpinus sp., 2 of them are on Abies sp. and one of them is on Fraxinus sp. Evernia prunastri (L.) Ach. is growing on both of Fagus sp. and Quercus sp. Lecanora pulicaris (Pers.) Ach. is growing on both of Abies sp. and Quercus sp.

Keywords: biodiversity, epiphytic lichen, forest, Turkey

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9158 A Faunistic Comparative Study of Families Hesperiidae and Nymphalidae (Lepidoptera: Rhopalocera) of Syrian Arab Republic and Republic of Armenia

Authors: N. Zarikian

Abstract:

Comparative analysis of the fauna of two families of butterflies (Lepidoptera: Rhopalocera) – Hesperiidae and Nymphalidae were carried out. In general, 122 species of the families are recorded. among these 33 species belong to Hesperiidae and 89 to Nymphalidae. The numbers by countries are as follows: 72 species are found in Syria (including 24 Hesperiidae and 48 Nymphalidae) and 97 in Armenia (26 and 71 species, respectively). Two species of Hesperiidae are reported for Syrian fauna for the first time and one species is newly recorded for Armenia. From the species above mentioned 38 are common both for Syria and Armenia. For estimation of the similarity of faunas studied were used the Jaccard index. By families the index is rather different, consisting for Hesperiidae 0.5151 and for Nymphalidae 0.337.

Keywords: Armenia, fauna, Hesperiidae, Nymphalidae, (Rhopalocera: Lepidoptera), Syria

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9157 Antimicrobial Effect of Natamycin against Food Spoilage Fungi and Yeast Contaminated Fermented Foods

Authors: Pervin Basaran Akocak

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Food antimicrobials are compounds that are incorporated into food matrixes in order to cause death or delay the growth of spoilage or pathogenic microorganisms. As a result, microbiological deterioration is prevented throughout storage and food distribution. In this study, the effect of natural antimycotic natamycin (C33H47NO13, with a molecular mass of 665.725), a GRAS (Generally Recognized As Safe) commercial compound produced by different strains of Streptomyces sp., was tested against various fermented food contamination fungi and yeast species. At the concentration of 100 µg/ml, natamycin exhibited stronger antifungal activity against fungi than yeast species tested. The exposure time of natamycin for complete inhibition of the species tested were found to be between 100-180 min at 300-750 µg/ml concentration. SEM observations of fungal species demonstrated that natamycin distorted and damaged the conidia and hyphae by inhibiting spore germination and mycelial growth. Natamycin can be considered as a potential candidate in hurdle food treatments for preventing fungal and yeast invasion and resulting deterioration of fermented products.

Keywords: natamycin, antifungal, fermented food, food spoilage fungi

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9156 Avifauna of Bara Gali Summer Campus, University of Peshawar, Khyber Pakhtunkhwa

Authors: Saif Ullah, Zaigham Hasan, Muhammad Ali, Qaisar Jamal, Kiran Salahuddin, Muhammad Awais

Abstract:

Survey of avian fauna of Bara Gali Summer Campus, University of Peshawar situated in Abbottabad was conducted from April to October, 2013. A total of 21 species belonging to 5 orders and 15 families were recorded. Out of these, 6 were resident, 12 summer visitor and 3 rare. Order Passeriformes was represented by 16 species which are Certhia himalayana, Megalaima virens, Phylloscopus trochiloides, Garrulax lineatus, Passer rutilans, Corvus macrorhynchos, Hypsipetes leucocephalus, Acridotheres tristis, Delichon dasypus cashmeriensis, Hirundo rustica, Muscicapa thalassina, Saxicola ferrea, Myiophoneus caeruleus, Parus melonolophus, Parus rufonuchalis, Parus monticolus, belonging to 11 families. Two species Dendrocopos himalayansis and Picus squamatus belong to only one family Picidae of order Piciformes. Among rest of the three orders each is represented by only a single species; Accipitriformes by Accipiter virgatus, Coraciformes by Upupa epops while order Psittaciformes has been represented by Psittacula himalayana. The distribution and abundance varied with season and maximum number of species were found during the monsoon season when most of the birds migrate for breeding. Some habits and behaviors like nesting, feeding, breeding and vocalizations were also studied which are very unique from other birds found at lower elevations. Among bird species adapted to diverse habitat in the field, Himalayan Jungle Crow, Common Mynas, Bulbuls, Barn Swallows, barbets were prominent. Interesting feature of the avian fauna is its familiarity with flora, was also observed during the present studies that some birds are very quick and active in their movement on a tree surface i.e Certhia himalayana.

Keywords: avifauna diversity, distribution, Bara Gali, Abbottabad

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9155 Assessment of the Spatio-Temporal Distribution of Pteridium aquilinum (Bracken Fern) Invasion on the Grassland Plateau in Nyika National Park

Authors: Andrew Kanzunguze, Lusayo Mwabumba, Jason K. Gilbertson, Dominic B. Gondwe, George Z. Nxumayo

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Knowledge about the spatio-temporal distribution of invasive plants in protected areas provides a base from which hypotheses explaining proliferation of plant invasions can be made alongside development of relevant invasive plant monitoring programs. The aim of this study was to investigate the spatio-temporal distribution of bracken fern on the grassland plateau of Nyika National Park over the past 30 years (1986-2016) as well as to determine the current extent of the invasion. Remote sensing, machine learning, and statistical modelling techniques (object-based image analysis, image classification and linear regression analysis) in geographical information systems were used to determine both the spatial and temporal distribution of bracken fern in the study area. Results have revealed that bracken fern has been increasing coverage on the Nyika plateau at an estimated annual rate of 87.3 hectares since 1986. This translates to an estimated net increase of 2,573.1 hectares, which was recorded from 1,788.1 hectares (1986) to 4,361.9 hectares (2016). As of 2017 bracken fern covered 20,940.7 hectares, approximately 14.3% of the entire grassland plateau. Additionally, it was observed that the fern was distributed most densely around Chelinda camp (on the central plateau) as well as in forest verges and roadsides across the plateau. Based on these results it is recommended that Ecological Niche Modelling approaches be employed to (i) isolate the most important factors influencing bracken fern proliferation as well as (ii) identify and prioritize areas requiring immediate control interventions so as to minimize bracken fern proliferation in Nyika National Park.

Keywords: bracken fern, image classification, Landsat-8, Nyika National Park, spatio-temporal distribution

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9154 Mathematical Modelling and Parametric Study of Water Based Loop Heat Pipe for Ground Application

Authors: Shail N. Shah, K. K. Baraya, A. Madhusudan Achari

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Loop Heat Pipe is a passive two-phase heat transfer device which can be used without any external power source to transfer heat from source to sink. The main aim of this paper is to have modelling of water-based LHP at varying heat loads. Through figures, how the fluid flow occurs within the loop has been explained. Energy Balance has been done in each section. IC (Iterative Convergence) scheme to find out the SSOT (Steady State Operating Temperature) has been developed. It is developed using Dev C++. To best of the author’s knowledge, hardly any detail is available in the open literature about how temperature distribution along the loop is to be evaluated. Results for water-based loop heat pipe is obtained and compared with open literature and error is found within 4%. Parametric study has been done to see the effect of different parameters on pressure drop and SSOT at varying heat loads.

Keywords: loop heat pipe, modelling of loop heat pipe, parametric study of loop heat pipe, functioning of loop heat pipe

Procedia PDF Downloads 388
9153 Ground Beetle’s Diversity in Agroecosystems of a Steppe Region, Algeria

Authors: Nawel Ganaoui, Chadli Souhila, Gahdab Chakal

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This study presents the results of a comparative research aiming to examine the distribution of beetles in four agroecosystems in the Tiaret region, located in northwestern Algeria, during the year 2023. This study was initiated across 04 stations that were randomly distributed within the Ksar Chellala region and selected based on their plant composition. The sampling method used was based on pitfall traps, which were filled two-thirds with a solution of saltwater supplemented with vinegar. In total, 40 species of beetles belonging to 9 families were identified. Among them, tenebrionids were the most abundant group (43%), followed by scarab beetles (30%) The comparison between the four types of agroecosystems - olive culture, sheep farming, cereal cultivation, and Pomegranate cultivation- in this region revealed that cereal cultivation harbored the greatest species diversity (30 species), followed by the sheep farming site (32 species), and then the other sites based on their ecological importance and trophic interactions, these beetle species were mainly categorized as coprophages, phytophages, and predators. The spatiotemporal evolution of beetle activity highlighted peaks of rich-ness and abundance, mainly during the dry period (from April to May), while the cold period (January) showed the low-est levels. The specific diversity of beetles varied significantly from one habitat to another.

Keywords: agroecosystem, beetle, entomology, steppe regoin

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