Thermal Model for Building External Wall under Low Atmospheric Pressure and High Solar Radiation Conditions in Plateau Area

Chapter 1 gives a brief overview of the climatic and terrestrial environment in which high altitude waters are embedded. This context is necessary to understand the prevailing environmental conditions in the aquatic systems. The chapter begins by defining high altitude, alpine, and mountain, and provides an overview of the distribution of the world’s main high altitude regions. The overall picture of the climatic setting is drawn, from the inevitable consequences of high altitude (low temperature, low atmospheric pressure, and high solar radiation) to the highly region-specific patterns in precipitation and wind. The various ways that highland regions are formed, their temporal evolution, and climatic changes are treated in a section on the palaeo-environmental perspective. Finally, general patterns in high altitude (alpine) vegetation zones and treelines on different continents are synthesized, as well as major soil-forming processes in the catchments surrounding aquatic systems.

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Effect of Low Temperature on Floral Induction of Eucalyptus lansdowneana F. Muell. & J. Brown subsp. lansdowneana

Australian Journal of Botany ◽

10.1071/bt9920157 ◽

1992 ◽

Vol 40 (2) ◽

pp. 157 ◽

Cited By ~ 13

Author(s):

MW Moncur

Keyword(s):

Solar Radiation ◽

Floral Induction ◽

Day Length ◽

Vegetative Development ◽

Breeding Programs ◽

Stage Of Development ◽

High Solar Radiation ◽

Low Levels ◽

Radiation Conditions ◽

Short Days

Transferring seedlings of Eucalyptus lansdowneana from a heated glasshouse (24/19°C) to a cold glasshouse (15/10°C) for 5 or 10 weeks and back to the heated glasshouse was sufficient to induce floral buds. Bud production was further enhanced when seedlings were transferred to cold conditions during periods of high solar radiation. Under low levels of solar radiation and short duration of cold, 0-5 weeks, plants reverted to vegetative development, suggesting a low floral induction stimulus. Seedlings that produced a visible floral inflorescence had fewer leaves than seedlings grown under similar conditions that had not produced an inflorescence. This was more noticeable under high-radiation conditions. Plants grown under outside conditions in Canberra and transferred to a heated glasshouse (25/ 18°C) during winter initiated inflorescences 7-9 weeks earlier than plants grown continuously outside. The early initiation enabled buds to develop and flower before the onset of the following winter. More buds were initiated in plants transferred to the glasshouse in September compared with 16 June or 28 July. Plants transferred on 16 June initiated few buds or none at all. These plants may have been in a juvenile or transitional stage of development, experienced insufficient cold for full induction or been limited by the low winter irradiances. Floral response occurred under both long days (phytotron) and short days under outside conditions in Canberra, suggesting that E. lansdowneana may well be relatively insensitive to day length. These results are discussed in relation to controlled breeding programs which aim to manipulate flowering time and duration to decrease the generation interval.

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485 PB 125 QUANTIFYING THE EFFECT OF PLUG-FLAT COLOR ON SOIL SURFACETEMPERATURE

HortScience ◽

10.21273/hortsci.29.5.500g ◽

1994 ◽

Vol 29 (5) ◽

pp. 500g-501

Author(s):

James E. Faust ◽

Hiroshi Shimizu ◽

Royal D. Heins

Keyword(s):

Solar Radiation ◽

Surface Temperature ◽

Soil Temperature ◽

Soil Surface ◽

Image Analyzer ◽

Fine Wire ◽

High Solar Radiation ◽

White Sheet ◽

Soil Surface Temperature ◽

Radiation Conditions

Surface temperature of a soilless medium in white, gray, and black plug sheets was measured to determine the value of using plug sheets of different colors to control soil temperature during seed germination and young seedling growth. Plugs sheets were placed in a greenhouse set at 25°C. Soil surface temperatures were measured with fine-wire thermocouples inserted into the top 1 mm of the soil. A thermal image analyzer was used to determine the temperature variation across the plug flat. At night, soil temperature in all three colored flats was 3°C below air temperature because of evaporation and net longwave radiative losses to the greenhouse glass. Surface temperature of moist soil increased as solar radiation increased. Soil surface temperature in the white sheet was 6.3 and 10°C warmer than the air under solar radiation conditions of 350 and 700 W ·m-2 (about 700 and 1400 μmol·m-2·s-1), which was 3 and 2°C cooler than soil the black and gray plug sheets, respectively. These data indicate plug sheet color influences soil surface temperature, but not as much as solar radiation does. Preventing high solar radiation during the summer is more critical than plug sheet color.

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