QUANTIFICATION OF EFFECTS PRODUCED BY THE EXTRACTION OF MINERAL AGGREGATES TOWARDS WATER BODIES

2017 ◽  
Vol 16 (4) ◽  
pp. 897-903
Author(s):  
Paula Cojocaru ◽  
Florian Statescu ◽  
Gabriela Biali
Author(s):  
Gejing Li ◽  
D. R. Peacor ◽  
D. S. Coombs ◽  
Y. Kawachi

Recent advances in transmission electron microscopy (TEM) and analytical electron microscopy (AEM) have led to many new insights into the structural and chemical characteristics of very finegrained, optically homogeneous mineral aggregates in sedimentary and very low-grade metamorphic rocks. Chemical compositions obtained by electron microprobe analysis (EMPA) on such materials have been shown by TEM/AEM to result from beam overlap on contaminant phases on a scale below resolution of EMPA, which in turn can lead to errors in interpretation and determination of formation conditions. Here we present an in-depth analysis of the relation between AEM and EMPA data, which leads also to the definition of new mineral phases, and demonstrate the resolution power of AEM relative to EMPA in investigations of very fine-grained mineral aggregates in sedimentary and very low-grade metamorphic rocks.Celadonite, having end-member composition KMgFe3+Si4O10(OH)2, and with minor substitution of Fe2+ for Mg and Al for Fe3+ on octahedral sites, is a fine-grained mica widespread in volcanic rocks and volcaniclastic sediments which have undergone low-temperature alteration in the oceanic crust and in burial metamorphic sequences.


EDIS ◽  
2017 ◽  
Vol 2017 (3) ◽  
pp. 3
Author(s):  
Travis W. Shaddox ◽  
Joseph Bryan Unruh

Nutrient applications are often required to meet Florida’s demand for agricultural and horticultural commodities, but often those applications occur in close proximity to water bodies. In order for scientists, policy makers, and citizens to make decisions regarding nutrient issues in Florida, it is important to first understand which markets contribute to Florida’s fertilizer consumption. This three-page fact sheet explains Florida’s fertilizer usage statistics. Written by T.W.Shaddox and published by the Environmental Horticulture Department.­http://edis.ifas.ufl.edu/ep541


1996 ◽  
Vol 8 (2) ◽  
pp. 90-104 ◽  
Author(s):  
Janette Lee

A model for more accurately representing the distribution of population is currently under development using some of the functionality of the Arc/Info GIS software. Included are factors for settlement pattern, topography and the presence of water bodies. The model is tested on County Antrim in Northern Ireland and the value of traditional choropleth mapping assessed in comparison with the output from the model.


2014 ◽  
Vol 25 (1-2) ◽  
pp. 61-68 ◽  
Author(s):  
V. I. Monchenko ◽  
L. P. Gaponova ◽  
V. R. Alekseev

Crossbreeding experiments were used to estimate cryptic species in water bodies of Ukraine and Russia because the most useful criterion in species independence is reproductive isolation. The problem of cryptic species in the genus Eucyclops was examined using interpopulation crosses of populations collected from Baltic Sea basin (pond of Strelka river basin) and Black Sea basin (water-reservoires of Dnieper, Dniester and Danube rivers basins). The results of reciprocal crosses in Eucyclops serrulatus-group are shown that E. serrulatus from different populations but from water bodies belonging to the same river basin crossed each others successfully. The interpopulation crosses of E. serrulatus populations collected from different river basins (Dnipro, Danube and Dniester river basins) were sterile. In this group of experiments we assigned evidence of sterility to four categories: 1) incomplete copulation or absence of copulation; 2) nonviable eggs; 3) absence of egg membranes or egg sacs 4) empty egg membranes. These crossbreeding studies suggest the presence of cryptic species in the E. serrulatus inhabiting ecologically different populations in many parts of its range. The same crossbreeding experiments were carries out between Eucyclops serrulatus and morphological similar species – Eucyclops macruroides from Baltic and Black Sea basins. The reciprocal crossings between these two species were sterile. Thus taxonomic heterogeneity among species of genus Eucyclops lower in E. macruroides than in E. serrulatus. The interpopulation crosses of E. macruroides populations collected from distant part of range were fertile. These crossbreeding studies suggest that E. macruroides species complex was evaluated as more stable than E. serrulatus species complex.


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