Author: Stephen L. Rawlins
Publisher:
ISBN:
Category : Soil moisture
Languages : en
Pages : 298
Book Description
The following advances in technology for measurement of water potential are described: (1) A thermocouple for direct attachment to plant leaves; (2) A microchamber for studying plant responses to environment is described. Light intensity and duration, ambient temperature, relative humidity, and CO2 concentration are controlled. Transpiration, CO2 assimilation, and plant and soil water potential are measured. Data for the ratio of transpiration to CO2 assimilation for cotton are given. Moderate salinity increased this ratio. Description of a contact closure distributor to make a data acquisition system serve as a control device as well as a recorder is given. Also described is a tape editor for handling output data from the system. Preliminary results from experiments to determine how plants integrate time varying salinity indicate that transpiration per unit leaf area is decreased by salinity. (Author).
Water Transfer from Soil to the Atmosphere as Related to Soil Properties, Plant Characteristics and Weather
Author: Stephen L. Rawlins
Publisher:
ISBN:
Category : Soil moisture
Languages : en
Pages : 298
Book Description
The following advances in technology for measurement of water potential are described: (1) A thermocouple for direct attachment to plant leaves; (2) A microchamber for studying plant responses to environment is described. Light intensity and duration, ambient temperature, relative humidity, and CO2 concentration are controlled. Transpiration, CO2 assimilation, and plant and soil water potential are measured. Data for the ratio of transpiration to CO2 assimilation for cotton are given. Moderate salinity increased this ratio. Description of a contact closure distributor to make a data acquisition system serve as a control device as well as a recorder is given. Also described is a tape editor for handling output data from the system. Preliminary results from experiments to determine how plants integrate time varying salinity indicate that transpiration per unit leaf area is decreased by salinity. (Author).
Publisher:
ISBN:
Category : Soil moisture
Languages : en
Pages : 298
Book Description
The following advances in technology for measurement of water potential are described: (1) A thermocouple for direct attachment to plant leaves; (2) A microchamber for studying plant responses to environment is described. Light intensity and duration, ambient temperature, relative humidity, and CO2 concentration are controlled. Transpiration, CO2 assimilation, and plant and soil water potential are measured. Data for the ratio of transpiration to CO2 assimilation for cotton are given. Moderate salinity increased this ratio. Description of a contact closure distributor to make a data acquisition system serve as a control device as well as a recorder is given. Also described is a tape editor for handling output data from the system. Preliminary results from experiments to determine how plants integrate time varying salinity indicate that transpiration per unit leaf area is decreased by salinity. (Author).
Water Transfer from Soil to the Atmosphere as Related to Soil Properties, Plant Characteristics and Weather
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 102
Book Description
A laboratory technique is described for independent measurement of the total soil water potential and its components, based on the principles of the soil psychrometer and the porous plate apparatus. Only a negligible quantity of soil water is displaced. Such data are used to study interactions of the water potential New plant growth chambers are being built at Riverside to study the transport of water from the soil to the atmosphere through plants. The sunlit plastic-enclosed chambers have provisions for control of temperature, humidity, CO2 concentration, light intensity, and air velocity. Each chamber will be 20 feet high, with nearly 10 feet below the soil surface level to accommodate deep soil columns. A pepper plant was grown through three irrigation cycles in a soil column 130 cm deep; soil water potential was measured with tensiometers and a thermocouple psychrometer; plant water potential was inferred from a calibrated beta gauge; transpiration was measured by weighing the soil-plant system. Water movement in the transpiration stream was in the direction of the water potential gradient. Regardless of the distribution of water in the soil, transpiration was unaffected by declining soil water until it reached a level corresponding to about -8 bars soil water potential. Beyond this, transpiration decreased linearly with soil water content to a soil water potential of -37 bars, at which time the plant water potential was below -50 bars and transpiration was essentially zero. After irrigation, the plant regained full turgor. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 102
Book Description
A laboratory technique is described for independent measurement of the total soil water potential and its components, based on the principles of the soil psychrometer and the porous plate apparatus. Only a negligible quantity of soil water is displaced. Such data are used to study interactions of the water potential New plant growth chambers are being built at Riverside to study the transport of water from the soil to the atmosphere through plants. The sunlit plastic-enclosed chambers have provisions for control of temperature, humidity, CO2 concentration, light intensity, and air velocity. Each chamber will be 20 feet high, with nearly 10 feet below the soil surface level to accommodate deep soil columns. A pepper plant was grown through three irrigation cycles in a soil column 130 cm deep; soil water potential was measured with tensiometers and a thermocouple psychrometer; plant water potential was inferred from a calibrated beta gauge; transpiration was measured by weighing the soil-plant system. Water movement in the transpiration stream was in the direction of the water potential gradient. Regardless of the distribution of water in the soil, transpiration was unaffected by declining soil water until it reached a level corresponding to about -8 bars soil water potential. Beyond this, transpiration decreased linearly with soil water content to a soil water potential of -37 bars, at which time the plant water potential was below -50 bars and transpiration was essentially zero. After irrigation, the plant regained full turgor. (Author).
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 332
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 332
Book Description
Government-wide Index to Federal Research & Development Reports
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1078
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1078
Book Description
Technical Abstract Bulletin
Author: Defense Documentation Center (U.S.)
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 784
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 784
Book Description
Water Resources Research Catalog
Author:
Publisher:
ISBN:
Category : Water resources development
Languages : en
Pages : 1464
Book Description
Publisher:
ISBN:
Category : Water resources development
Languages : en
Pages : 1464
Book Description
U.S. Government Research Reports
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 162
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 162
Book Description
Selected Water Resources Abstracts
Author:
Publisher:
ISBN:
Category : Hydrology
Languages : en
Pages : 584
Book Description
Publisher:
ISBN:
Category : Hydrology
Languages : en
Pages : 584
Book Description
Building Soils for Better Crops
Author: Fred Magdoff
Publisher: Sare
ISBN: 9781888626131
Category : Humus
Languages : en
Pages : 294
Book Description
"'Published by the Sustainable Agriculture Research and Education (SARE) program, with funding from the National Institute of Food and Agriculture, U.S. Department of Agriculture."
Publisher: Sare
ISBN: 9781888626131
Category : Humus
Languages : en
Pages : 294
Book Description
"'Published by the Sustainable Agriculture Research and Education (SARE) program, with funding from the National Institute of Food and Agriculture, U.S. Department of Agriculture."
U.S. Government Research & Development Reports
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 384
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 384
Book Description