Ecological diversification among nine species of Pohlia (Musci) in western North America

1981 ◽  
Vol 59 (12) ◽  
pp. 2359-2378 ◽  
Author(s):  
A. Jonathan Shaw
Keyword(s):  
North America ◽  
Organic Matter Content ◽  
Matter Content ◽  
Similar Species ◽  
Western North America ◽  
Geographic Ranges ◽  
Ecological Diversification ◽  
Variable Species ◽  
Calcium And Magnesium Ions ◽  
Broad Region

Nine North American species of Pohlia, section Pohliella, form a complex of morphologically and ecologically similar species. In western North America, where there is a broad region of overlap in geographic ranges, they frequently grow together in various combinations. Over 300 soil samples representative of these species were analyzed with respect to organic matter content, pH, and concentrations of exchangeable calcium and magnesium ions, and each species was found to be distinctive in terms of these environmental factors. Morphologically variable species tend to be ecologically and geographically widespread, while less variable species tend to be more restricted. Species with a predominance of primitive morphological features occur primarily on tundra soils of intermediate pH, while morphologically advanced species inhabit road banks or other disturbed sites where the pH may be high or low.

The Effects of Long‐Term Land‐Use Change on Soil Properties in Perth, Ontario Canada

2016 ◽  
Author(s):  
Trina Stephens
Keyword(s):  
Land Use ◽  
Organic Matter ◽  
North America ◽  
Land Use Change ◽  
Soil Properties ◽  
Carbon Storage ◽  
Organic Matter Content ◽  
Matter Content ◽  
Topographic Gradients

Land‐use change can have a major impact on soil properties, leading to long‐term changes in soilnutrient cycling rates and carbon storage. While a substantial amount of research has been conducted onland‐use change in tropical regions, empirical evidence of long‐term conversion of forested land toagricultural land in North America is lacking. Pervasive deforestation for the sake of agriculturethroughout much of North America is likely to have modified soil properties, with implications for theglobal climate. Here, we examined the response of physical, chemical and biological soil properties toconversion of forest to agricultural land (100 years ago) on Roebuck Farm near Perth, Ontario, Canada.Soil samples were collected at three sites from under forest and agricultural vegetative cover on bothhigh‐ and low‐lying topographic positions (12 locations in total; soil profile sampled to a depth of 40cm).Our results revealed that bulk density, pH, and nitrate concentrations were all higher in soils collectedfrom cultivate sites. In contrast, samples from forested sites exhibited greater water‐holding capacity,porosity, organic matter content, ammonia concentrations and cation exchange capacity. Many of these characteristics are linked to greater organic matter abundance and diversity in soils under forestvegetation as compared with agricultural soils. Microbial activity and Q10 values were also higher in theforest soils. While soil properties in the forest were fairly similar across topographic gradients, low‐lyingpositions under agricultural regions had higher bulk density and organic matter content than upslopepositions, suggesting significant movement of material along topographic gradients. Differences in soilproperties are attributed largely to increased compaction and loss of organic matter inputs in theagricultural system. Our results suggest that the conversion of forested land cover to agriculture landcover reduces soil quality and carbon storage, alters long‐term site productivity, and contributes toincreased atmospheric carbon dioxide concentrations.

Morphological and chromosomal variation in Dodecatheon pulchellum (Primulaceae)

1992 ◽  
Vol 70 (12) ◽  
pp. 2476-2483 ◽  
Author(s):  
Terri A. Suttill ◽  
Geraldine A. Allen
Keyword(s):  
North America ◽  
Morphological Variation ◽  
Genetic Basis ◽  
Common Garden ◽  
Chromosomal Variation ◽  
Western North America ◽  
Chromosome Counts ◽  
Alpine Habitats ◽  
Variable Species ◽  
Ecological Differences

Dodecatheon pulchellum (Raf.) Merr. is a widespread and morphologically variable species of western North America. Analysis of morphological variation, combined with chromosome counts and evidence from a transplant study, showed this species to consist of two subspecies. Subspecies cusickii is pubescent, mainly diploid, and occurs in the drier parts of the species range. The more variable ssp. pulchellum is glabrous to sparsely pubescent, mainly polyploid, and is widely distributed. Within ssp. pulchellum, three varieties can be recognized: the tall, many-flowered var. alaskanum, of wet, low-elevation habitats; the diminutive var. watsonii, generally of alpine habitats; and the intermediate and widely distributed var. pulchellum. Common garden studies indicate that size differences among these varieties have a genetic basis and that ecological differences exist in D. pulchellum even among morphologically similar forms. Key words: Dodecatheon, Primulaceae, systematics, morphology, chromosome numbers, common garden studies.

Species of Cortinarius subgenus Leprocybe, sections Orellani and Limonei, in North America

1994 ◽  
Vol 72 (4) ◽  
pp. 520-532 ◽  
Author(s):  
R. G. Thorn ◽  
D. W. Malloch
Keyword(s):  
North America ◽  
Morphological Characters ◽  
The Other ◽  
Mushroom Poisoning ◽  
Eastern North America ◽  
Similar Species ◽  
Western North America ◽  
Genetic Studies ◽  
Rdna Sequences ◽  
Fluorescent Compounds

Descriptions and a key are provided to seven species of Cortinarius subg. Leprocybe, sect. Orellani and Limonei, that are found in North America, namely C. callisteus (synonym C. croceocolor), C. distans var. olympianus, C. gentilis (synonym C. confusus), C. limoneus (synonym C. whiteae), C. morrisii, C. rainierensis, and C. speciosissimus. Of these, C. rainierensis and C. speciosissimus were previously shown to contain the nephrotoxin orellanine. Reports of C. orellanus from North America were based on misidentifications of C. uliginosus or similar species of subg. Dermocybe. There are no apparent morphological features to distinguish C. speciosissimus, which has been found in eastern North America, from C. rainierensis, which is known only from the state of Washington in western North America, or from C. orellanoides, which was described from France. Since morphological characters were found for the distinction of sibling species discovered by biochemical and genetic studies in other genera, including Armillaria, we prefer not to accept or suggest the synonymy of these taxa until neotypes or lectotypes are selected for C. croceocolor and C. rubellus and these specimens are compared with types of the other available names using chromatography of fluorescent compounds or rDNA sequences. Key words: biosystematics, mushroom poisoning, orellanine.

HYBOMITRA AGORA, A NEW SPECIES OF TABANIDAE (DIPTERA) FROM WESTERN NORTH AMERICA

1987 ◽  
Vol 119 (12) ◽  
pp. 1117-1122 ◽  
Author(s):  
H.J. Teskey ◽  
J.A. Shemanchuk ◽  
J. Weintraub
Keyword(s):  
New Species ◽  
North America ◽  
Mating Behavior ◽  
Sympatric Species ◽  
Similar Species ◽  
Western North America ◽  
A New Species

AbstractBoth sexes of Hybomitra agora new species are described and differentiated from similar species in western North America. Notes are given on the known habitat of H. agora and on differences in mating behavior between this and three other sympatric species of Hybomitra. Known distribution of H. agora is summarized with a map.

Five new Telamonia species (Cortinarius, Agaricales) from western North America

Botany ◽  
2013 ◽  
Vol 91 (7) ◽  
pp. 478-485 ◽  
Author(s):  
Tuula Niskanen ◽  
Kare Liimatainen ◽  
Joseph F. Ammirati
Keyword(s):  
North America ◽  
Phylogenetic Relationships ◽  
Similar Species ◽  
Western North America ◽  
Posterior Probabilities

Five new Cortinarius species in subgenus Telamonia are described from western North America: Cortinarius alboambitus Niskanen, Liimat. & Ammirati sp. nov., Cortinarius brunneovernus Niskanen, Liimat. & Ammirati sp. nov., Cortinarius fructuodorus Niskanen, Liimat. & Ammirati sp. nov., Cortinarius nauseosouraceus Niskanen, Liimat. & Ammirati sp. nov., and Cortinarius politus Niskanen, Liimat. & Ammirati sp. nov. Phylogenetic relationships of the species were inferred by analysis of ITS and rpb2. The placement of C. brunneovernus in sect. Brunnei, C. fructuodotus in sect. Telamonia, and C. nauseosouraceus in sect. Cinnabarini/Uracei/Colymbadini is strongly supported. Cortinarius alboambitus grouped with species in the clade Furvolaesi with a support of 0.83 posterior probabilities, and C. politus with the species in sect. Boulderenses with 0.67 posterior probabilities. The descriptions of these species are presented and a comparison with similar species is provided.

HEAVY METAL SPECIATION IN BOTTOM SEDIMENTS OF THE VYSHNEVOLOTSKY RESERVOIR

2018 ◽  
pp. 46-54
Author(s):  
O. A. Lipatnikova
Keyword(s):  
Heavy Metal ◽  
Organic Matter ◽  
Bottom Sediments ◽  
Metal Speciation ◽  
Organic Matter Content ◽  
Water Reservoir ◽  
Matter Content ◽  
Heavy Metal Speciation ◽  
Mobile Forms ◽  
Manganese Hydroxides

The study of heavy metal speciation in bottom sediments of the Vyshnevolotsky water reservoir is presented in this paper. Sequential selective procedure was used to determine the heavy metal speciation in bottom sediments and thermodynamic calculation — to determine ones in interstitial water. It has been shown that Mn are mainly presented in exchangeable and carbonate forms; for Fe, Zn, Pb и Co the forms are related to iron and manganese hydroxides is played an important role; and Cu and Ni are mainly associated with organic matter. In interstitial waters the main forms of heavy metal speciation are free ions for Zn, Ni, Co and Cd, carbonate complexes for Pb, fulvate complexes for Cu. Effects of particle size and organic matter content in sediments on distribution of mobile and potentially mobile forms of toxic elements have been revealed.

Physico-Chemical Properties of Soil Collected from Chandrabhaga River in Kalmeshwar, Nagpur, Maharashtra

2020 ◽  
Vol 07 (02) ◽  
pp. 1-3
Author(s):  
Amita M Watkar ◽  
Keyword(s):  
Organic Matter ◽  
Soil Quality ◽  
Agricultural Land ◽  
Organic Matter Content ◽  
Chemical Properties ◽  
Matter Content ◽  
Soil Attributes ◽  
Essential Components ◽  
Agricultural Land Management ◽  
Physical And Chemical

Soil, itself means Soul of Infinite Life. Soil is the naturally occurring unconsolidated or loose covering on the earth’s surface. Physical properties depend upon the amount, size, shape, arrangement, and mineral composition of soil particles. It also depends on the organic matter content and pore spaces. Chemical properties depend on the Inorganic and organic matter present in the soil. Soils are the essential components of the environment and foundation resources for nearly all types of land use, besides being the most important component of sustainable agriculture. Therefore, assessment of soil quality and its direction of change with time is an ideal and primary indicator of sustainable agricultural land management. Soil quality indicators refer to measurable soil attributes that influence the capacity of a soil to function, within the limits imposed by the ecosystem, to preserve biological productivity and environmental quality and promote plant, animal and human health. The present study is to assess these soil attributes such as physical and chemical properties season-wise.

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