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Revision of the Far East Asian Aphidiidae (Hymenoptera)

Revision of the Far East Asian Aphidiidae (Hymenoptera)

Autor: P. Starý , E.i. Schlinger

Número de Páginas: 222
Handbook of Flowering

Handbook of Flowering

Autor: Abraham H. Halevy

Número de Páginas: 590

These volumes are an exhaustive source of information on the control and regulation of flowering. They present data on the factors controlling flower induction and how they may be affected by climate and chemical treatments. For each plant, specific information is provided on all aspects of flower development, including sex expression, requirements for flowering initiation and development, photoperiod, light density, vernalization, and other temperature effects and interactions. Individual species are described from the standpoint of juvenility and maturation, morphology, induction and morphogenesis to anthesis. All information is presented alphabetically for easy reference

Canadian Naturalist and Geologist and Proceedings of the Natural History Society of Montreal

Canadian Naturalist and Geologist and Proceedings of the Natural History Society of Montreal

Número de Páginas: 510
History of that Part of the Susquehanna and Juniata Valleys

History of that Part of the Susquehanna and Juniata Valleys

Autor: Franklin Ellis , Austin N. Hungerford

Número de Páginas: 934
Woodland Conservation and Management

Woodland Conservation and Management

Autor: G. F. Peterken

Número de Páginas: 337

Professor John Harper, in his recent Population Biology of Plants (1977), made a comment and asked a question which effectively states the theme of this book. Noting that 'one of the consequences of the development of the theory of vegetational climax has been to guide the observer's mind forwards', i. e. that 'vegetation is interpreted asa stage on the way to something', he commented that 'it might be more healthy and scientifically more sound to look more often backwards and search for the explanation of the present in the past, to explain systems in relation to their history rather than their goal'. He went on to contrast the 'disaster theory' of plant succession, which holds that communities are a response to the effects of past disasters, with the 'climax theory', that they are stages in the approach to a climax state, and then asked 'do we account most completely for the characteristics of a population by a knowledge of its history or of its destiny?' Had this question been put to R. S. Adamson, E. J. Salisbury, A. G. Tansley or A. S. Watt, who are amongst the giants of the first forty years of woodland ecology in Britain, their answer would surely have been that...

Coccids of the Far-Eastern USSR (Homoptera, Coccinea)

Coccids of the Far-Eastern USSR (Homoptera, Coccinea)

Autor: Evlina Markovna Dant︠s︡ig

Número de Páginas: 488
The Proceedings and Transactions of the Nova Scotian Institute of Science

The Proceedings and Transactions of the Nova Scotian Institute of Science

Autor: Nova Scotian Institute Of Science

Número de Páginas: 590
Arboretum et fruticetum Britannicum; or, The trees and shrubs of Britain ... pictorically and botanically delineated, and scientifically and popularly described ...

Arboretum et fruticetum Britannicum; or, The trees and shrubs of Britain ... pictorically and botanically delineated, and scientifically and popularly described ...

Autor: John Claudius Loudon

Número de Páginas: 754
Arboretum Et Fruticetum Britannicum, Or, The Trees and Shrubs of Britain

Arboretum Et Fruticetum Britannicum, Or, The Trees and Shrubs of Britain

Autor: J. C. Loudon

Número de Páginas: 756
Bumble Bees and Cuckoo Bumble Bees of California (Hymenoptera, Apidae)

Bumble Bees and Cuckoo Bumble Bees of California (Hymenoptera, Apidae)

Autor: Robbin W. Thorp , Donald S. Horning , Lorry L. Dunning

Número de Páginas: 100
Report of the Northern Great Plains Field Station for the 10-year Period, 1913-1922, Inclusive

Report of the Northern Great Plains Field Station for the 10-year Period, 1913-1922, Inclusive

Número de Páginas: 88
A First Report on the Relations Between Climates and Crops

A First Report on the Relations Between Climates and Crops

Autor: Cleveland Abbe

Número de Páginas: 406

Summary of expert opinion published up to 1891, on seed germination; soil temperature and moisture; solar energy; atmospheric conditions; and influences of climate; with data for selected U.S. and foreign locations.

The Boreal Ecosystem

The Boreal Ecosystem

Autor: James A. Larsen

Número de Páginas: 517

The Boreal Ecosystem presents an overview of the state of knowledge on the boreal forest region of North America, with extensive reference to the boreal regions of Europe and Asia. Initial sections of this book deal with aspects of the floristic composition and evolutionary history of the boreal vegetation. These introduce subsequent discussions on the processes at work in vegetation, soils, and the atmosphere—in short, with the boreal forest as an ecosystem, the sum total of the influences of many closely interlaced biotic and physical factors. These include not only plant species that make up the visible vegetation but also nutrients, soil, temperature, rainfall, progression of the seasons, soil microflora, arthropods, insects, and larger animals such as marten, otter, beaver, moose, caribou, bear, and wolf, and man. All are closely linked strands in the web of life, a web apart from, yet dependent on and influencing, the raw physical environment. This book should serve as an introduction and reference source to its audience: undergraduate and graduate students in the biological and ecological disciplines, research workers in these fields as well as in related areas such as...

Miscellaneous Publications

Miscellaneous Publications

Autor: Geological And Geographical Survey Of The Territories (u.s.)

Número de Páginas: 816
Potential Evapotranspiration and Climate in Alaska by Thornthwaite's Classification

Potential Evapotranspiration and Climate in Alaska by Thornthwaite's Classification

Autor: James H. Patric , Peter E. Black

Número de Páginas: 806
Birds of the Northwest

Birds of the Northwest

Autor: Elliott Coues

Número de Páginas: 816

This volume is based mainly on an unpublished report prepared by Coues in 1862 from the ornithological collections of F.V. Hayden and G.H. Trook taken during an expedition under Captain W.F. Raynolds, United States Engineers. The author preserved the "List of Specimens" tabulated in the original report, and extended the list with additional material from other collection trips in the West to compile what amounted to a "treatise on the Ornithology of the Western Territories," a desire expressed by F.V. Hayden to Coues.

Birds of the northwest: a hand-book of the ornithology of the region drained by the Missouri river and its tributaries, by E. Coues. 1874

Birds of the northwest: a hand-book of the ornithology of the region drained by the Missouri river and its tributaries, by E. Coues. 1874

Autor: Geological And Geographical Survey Of The Territories (u.s.)

Número de Páginas: 816
Economy and Society in the Transformation of the World

Economy and Society in the Transformation of the World

Autor: Mike Gonzalez , Salustiano Del Campo Urbano , Roberto Mesa

Número de Páginas: 226

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