scholarly journals Assessing the potential environmental factors affecting cladoceran assemblage composition in arsenic-contaminated lakes near abandoned silver mines

2021 ◽  
Vol 80 (2) ◽  
Author(s):  
Branaavan Sivarajah ◽  
Jesse C. Vermaire ◽  
John P. Smol
Keyword(s):  
Mining Activities ◽  
Regional Survey ◽  
Mining Pollution ◽  
Site Specific ◽  
Factors Affecting ◽  
Biological Surveys ◽  
Cladocera Remains ◽  
Silver Mining ◽  
Environmental Legacy ◽  
Study Sites

Silver mining has a long history in Cobalt (Ontario, Canada), and it has left a complex environmental legacy where many lakes are contaminated with arsenic-rich mine tailings. In this exploratory survey, we examined subfossil Cladocera remains in the surface sediments of 22 lakes in the abandoned mining region to assess which environmental variables may be influencing the recent assemblage structure. Further, using a “top-bottom” paleolimnological approach, we compared the recent (top) and older (bottom) assemblages from a subset of 16 lakes to determine how cladoceran composition has changed in these lakes. Our regional survey suggests that the cladoceran assemblages in the Cobalt area are primarily structured by differences in lake depth, while site-specific limnological characteristics, including those related to past mining activities, may have limited roles in shaping the recent cladoceran compositions. The top-bottom paleolimnological analysis suggests that the cladoceran assemblages have changed in most lakes around Cobalt, however the magnitude and nature of changes varied across the study sites. As with most regional biological surveys, the responses to historical mining activities were not uniform across all sites, which further emphasizes the importance of considering site-specific limnological characteristics and multiple environmental stressors when assessing the impacts of mining pollution.

scholarly journals Spatial distribution of the Barbary Partridge (Alectoris barbara) in Sardinia explained by land use and climate

2021 ◽  
Vol 67 (4) ◽  
Author(s):  
Gianpasquale Chiatante ◽  
Marta Giordano ◽  
Anna Vidus Rosin ◽  
Oreste Sacchi ◽  
Alberto Meriggi
Keyword(s):  
Land Use ◽  
Conservation Status ◽  
Distance Sampling ◽  
Strong Relationship ◽  
European Population ◽  
Factors Affecting ◽  
Brood Rearing ◽  
Management Actions ◽  
Negative Effect ◽  
Study Sites

AbstractMore than half of the European population of the Barbary Partridge is in Sardinia; nonetheless, the researches concerning this species are very scarce, and its conservation status is not defined because of a deficiency of data. This research aimed to analyse the habitat selection and the factors affecting the abundance and the density of the Barbary Partridge in Sardinia. We used the data collected over 8 years (between 2004 and 2013) by spring call counts in 67 study sites spread on the whole island. We used GLMM to define the relationships between the environment (topography, land use, climate) both the occurrence and the abundance of the species. Moreover, we estimated population densities by distance sampling. The Barbary Partridge occurred in areas at low altitude with garrigue and pastures, avoiding woodlands and sparsely vegetated areas. We found a strong relationship between the occurrence probability and the climate, in particular, a positive relation with temperature and a negative effect of precipitation, especially in April–May, during brood rearing. Furthermore, dry crops positively affected the abundance of the species. We estimated a density of 14.1 partridges per km2, similar to other known estimates. Our findings are important both because they increase the knowledge concerning this species, which is considered data deficient in Italy, and because they are useful to plan management actions aimed to maintain viable populations if necessary.

scholarly journals A method for reconstructing past lake water phosphorus concentrations using sediment geochemical records

2021 ◽  
Author(s):  
Madeleine Moyle ◽  
John F. Boyle
Keyword(s):  
Lake Water ◽  
Water Quality Monitoring ◽  
Specific Reference ◽  
Site Specific ◽  
Burial Rate ◽  
Steady State Model ◽  
Sediment Records ◽  
Current Water ◽  
Study Sites

AbstractAn existing steady state model of lake phosphorus (P) budgets has been adapted to allow reconstruction of long-term average historic lake water total phosphorus (TP) concentrations using lake sediment records of P burial. This model can be applied without site-specific parameterisation, thus potentially having universal application. In principle, it is applicable at any site where there is both a sediment P burial record and knowledge of the current water budget, although we advise caution applying it to problematic sediment records. Tested at six published case study sites, modelled lake water TP concentrations agree well with water-quality monitoring data, and limited testing finds good agreement with wholly independent diatom inferred lake water TP. Our findings, together with a review of the literature, suggest that well preserved lake sediments can usefully record a long-term average P burial rate from which the long-term mean lake water TP can be reliably estimated. These lake water TP reconstructions can provide meaningful site-specific reference values to support decision making in lake eutrophication management, including establishing targets for lake restoration.

scholarly journals Global Desert Areas Vs Local Mining Areas from Maramureș County (Romania)

2020 ◽  
pp. 45-52
Author(s):  
Bogdan-Vasile Cioruța ◽  
Mirela Coman
Keyword(s):  
Comparative Study ◽  
Mining Activities ◽  
Common Elements ◽  
Mining Pollution ◽  
Mining Areas ◽  
Desert Areas ◽  
Semi Arid

Almost a third of the Earth's surface is occupied by vast stretches of stone and sand, having a torrid climate or, on the contrary, extremely frigid. As such, the regions considered to fall into the category of deserts, which can be hot and arid, semi-arid, coastal, or cold, are of interest for the present study. In the same context, at the level of the Maramureș County surface, a major place is occupied by the areas that have served mining activities, and which, at first glance, have similarities with the specific landscapes of deserts. Starting from the aforementioned, through the present work, we intend to underline, in the form of a comparative study, the main common elements that exist between the naturally formed (globally) and anthropic (locally) deserts, for those the latter considering the areas of Maramures County, affected by the specific mining pollution.

Site-Specific Factors Affecting Corn Response to Starter Fertilizer

jpa ◽  
1999 ◽  
Vol 12 (4) ◽  
pp. 664-670 ◽  
Author(s):  
L. G. Bundy ◽  
T. W. Andraski
Keyword(s):  
Site Specific ◽  
Factors Affecting ◽  
Starter Fertilizer ◽  
Specific Factors

scholarly journals Pollinator richness and abundance in Northeast Estonia: bumblebees, butterflies and day-flying moths

2010 ◽  
Vol 53 (1) ◽  
pp. 5-14
Author(s):  
Isabel Diaz-Forero ◽  
Ave Liivamägi ◽  
Valdo Kuusemets ◽  
Jaan Luig
Keyword(s):  
Species Richness ◽  
Power Plants ◽  
Field Work ◽  
Mining Activities ◽  
Significant Relationships ◽  
Local Abundance ◽  
Second Year ◽  
Study Sites ◽  
Species Richness And Abundance ◽  
Insect Species Richness

Pollinator richness and abundance in Northeast Estonia: bumblebees, butterflies and day-flying moths We studied diversity and abundance of three groups of pollinators: bumblebees, butterflies and day-flying moths, in Ida-Viru County, Estonia. The field work was done during the summers of 2008 and 2009, in 22 semi-natural meadows located across Northeast Estonia. In total, we found 22 species of bumblebees (gen. Bombus), including 5 species of cuckoo bumblebees, 56 species of butterflies and 42 species of day-flying moths. We recorded 597 individuals of bumblebees, 768 individuals of butterflies and 330 individuals of day-flying moths in our study sites. We analysed differences between years (2008 and 2009) for the species richness and abundance of bumblebees, butterflies and day-flying moths; the relationships between insect species richness and area of meadow, the total number of species per meadow and the local abundance of each species separately. We found significant differences between bumblebee richness and abundance in 2008 and 2009, and between butterfly abundance at the same years. These differences may be due to more favourable conditions: warmer and dryer weather in the second year. We found no significant relationships between area of meadow and species richness of bumblebees, butterflies and day-flying moths; however, when we analysed the abundance of each species separately, we found that two species of bumblebees, i.e. B. pascuorum and B. schrencki, and one species of day-flying moths, i.e. Chiasmia clathrata, were negatively related with area of meadow. Although, Northeast Estonia is a region that has been environmentally affected by mining activities and the presence of power plants, it could be considered an important area that supports a significant richness and abundance of pollinators across its territory.

scholarly journals Allometric Models for Estimating Tree Volume and Aboveground Biomass in Lowland Forests of Tanzania

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Wilson Ancelm Mugasha ◽  
Ezekiel Edward Mwakalukwa ◽  
Emannuel Luoga ◽  
Rogers Ernest Malimbwi ◽  
Eliakimu Zahabu ◽  
...  
Keyword(s):  
Aboveground Biomass ◽  
Site Specific ◽  
Tree Allometry ◽  
Allometric Models ◽  
Specific Biomass ◽  
Lowland Forests ◽  
Study Sites ◽  
Biased Estimates ◽  
Total Tree ◽  
Volume Models

Models to assist management of lowland forests in Tanzania are in most cases lacking. Using a sample of 60 trees which were destructively harvested from both dry and wet lowland forests of Dindili in Morogoro Region (30 trees) and Rondo in Lindi Region (30 trees), respectively, this study developed site specific and general models for estimating total tree volume and aboveground biomass. Specifically the study developed (i) height-diameter (ht-dbh) models for trees found in the two sites, (ii) total, merchantable, and branches volume models, and (iii) total and sectional aboveground biomass models of trees found in the two study sites. The findings show that site specific ht-dbh model appears to be suitable in estimating treeheightsince the tree allometry was found to differ significantly between studied forests. The developed general volume models yielded unbiased mean prediction error and hence can adequately be applied to estimate tree volume in dry and wet lowland forests in Tanzania. General aboveground biomass model appears to yield biased estimates; hence, it is not suitable when accurate results are required. In this case, site specific biomass allometric models are recommended. Biomass allometric models which include basic wood density are highly recommended for improved estimates accuracy when such information is available.

scholarly journals An Evaluation of Factors Affecting the Choice of Coastal Recreational Activities

2011 ◽  
Vol 43 (2) ◽  
pp. 167-179 ◽  
Author(s):  
Krishna P. Paudel ◽  
Rex H. Caffey ◽  
Nirmala Devkota
Keyword(s):  
Multinomial Logit Model ◽  
Coastal Development ◽  
Internet Survey ◽  
Site Specific ◽  
Factors Affecting ◽  
Recreational Activities ◽  
Factors Influencing ◽  
Louisiana Coast ◽  
Coastal Louisiana

A visitor's decision to use a particular recreational site is influenced by the individual's taste as well as the characteristics of the site. For this reason, improved knowledge of the visitors' interests and factors influencing their choices are vital for both planning and policy formulations in coastal development. This study examines visitor characteristics and desired site-specific characteristics in order to determine the factors affecting use of the Louisiana coast for specific recreational purposes. We use a multinomial logit model and internet survey data to evaluate the factors affecting individuals' decisions to visit coastal Louisiana for a specific use. Results suggest that the major variables affecting the choice of coastal recreational activities include environmental quality of the site, income, and travel time.

scholarly journals Livelihood strategies of two small-scale fisher communities: adaptation strategies under different fishery resource at southern and northern coast of Java

2021 ◽  
Vol 919 (1) ◽  
pp. 012010
Author(s):  
Suadi ◽  
Z N A Nissa ◽  
R I Widyana ◽  
B K D Atmojo ◽  
H Saksono ◽  
...  
Keyword(s):  
Natural Capital ◽  
Livelihood Strategies ◽  
Small Scale ◽  
Northern Coast ◽  
Sustainable Livelihood ◽  
Fishery Resource ◽  
Factors Affecting ◽  
Small Scale Fisheries ◽  
Study Sites ◽  
Capital Ownership

Abstract Small-scale fishers are frequently exposed to a variety of hazards that threaten their livelihood. Different socio-cultural, natural resource, environment conditions potentially create unique vulnerability and livelihood strategies which may exist in different places. Therefore, an investigation in two different fishing communities was carried out to understand the similarities and different of livelihood strategy works in both places. The study was conducted in two small scale fisheries community in village Betahlawang (north of java) and Glagah (south of Java). This research aims to describe livelihood aspects and strategies of fisher communities in both locations under different fishery resource and their dependency on the fishery through systematic surveys. The study showed that both communities are highly dependent on natural capital which mainly the abundance of the fishery resources. Others factors affecting both communities’ sustainable livelihood are the uncertainty in catch, weather and policy, limited capital ownership, access, and knowledge and skills other than fishing. Although the two study sites share some capital similarities, the livelihood vulnerability and their strategy is different. Betahlawang fishers more vulnerable than Glagah fishers because Glagah fishers has more diverse livelihood alternatives.

scholarly journals Comparison of Two PARAFAC Models of Dissolved Organic Matter Fluorescence for a Mid-Atlantic Forested Watershed in the USA

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
Shatrughan Singh ◽  
Shreeram Inamdar ◽  
Durelle Scott
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Specific Model ◽  
Forested Watershed ◽  
Strongly Correlated ◽  
Site Specific ◽  
The Usa ◽  
Study Sites ◽  
Model Components ◽  
A Site

The composition of dissolved organic matter (DOM) in a mid-Atlantic forested watershed was evaluated using two fluorescence models—one based on previously validated model (Cory and McKnight, 2005) and the other developed specifically for our study site. DOM samples for the models were collected from multiple watershed sources over a two-year period. The previously validated parallel factor analysis (PARAFAC) model had 13 DOM components whereas our site-specific model yielded six distinct components including two terrestrial humic-like, two microbial-derived humic-like, and two protein-like components. The humic-like components were highest in surficial watershed sources and decreased from soil water to groundwater whereas the protein-like components were highest for groundwater sources. Discriminant analyses indicated that our site-specific model was more sensitive to subtle differences in DOM and the sum of the humic- and protein-like constituents yielded more pronounced differences among watershed sources as opposed to the prevalidated model. Dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) concentrations and selected DOM metrics were also more strongly correlated with the site-specific model components. These results suggest that while the pre-validated model may capture broader trends in DOM composition and allow comparisons with other study sites, a site-specific model will be more sensitive for characterizing within-site differences in DOM.

Authors Review on Drug Nanocrystals: A Progress to Targeted Delivery

2020 ◽  
Vol 10 (3) ◽  
pp. 248-270
Author(s):  
Manish Kumar ◽  
Nithya Shanthi ◽  
P.S. Rajnikanth ◽  
Arun Kumar Mahato
Keyword(s):  
Targeted Delivery ◽  
Scale Up ◽  
Biological Properties ◽  
Third Generation ◽  
Preparation Methods ◽  
Site Specific ◽  
Factors Affecting ◽  
Optimization Parameters ◽  
Pharmaceutical Industries ◽  
Surface Modified

In the last few decades, researchers and pharmaceutical industries have been developing new approaches to overcome the solubility and bioavailability limits observed with poorly soluble drugs. With the advancement of nanotechnology, nanocrystals have emerged as a great potential to overcome these limitations. Nanocrystals owing to its ability to modify the physicochemical and biological properties of the drug have gained widespread attention among the research scientists. This review provides comprehensive detail on the associated advantages, challenges, factors affecting physicochemical properties, and optimization parameters about the stability of nanocrystals. In this review, the evolution of nanocrystals is discussed as first-generation simple nanocrystals, secondgeneration nanocrystals within a carrier, and third-generation surface-modified nanocrystals. It also provides a detailed account of various preparation methods and evaluation of surface-modified nanocrystals. In the proposed "King Design," nanocrystals of the third generation are placed on the top due to their advantage over other nanocarriers like high drug payload, site-specific delivery, improved activity, commercial manufacturing, and easy scale-up. Third generations nanocrystals can provide a novel therapeutic solution for the site-specific, targeted, and efficient delivery for treatment of various acute as well as chronic diseases with high stability and scale-up potential.

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