Termokapl Higrometre/Psikrometre ile Yaprak Su Potansiyelinin Ölçülmesi

Yıl 1995, Cilt: 8 Sayı: 1, 380 - 392, 01.12.1995

Ruhi Baştuğ Suat Irmak

Öz

Bitkiler, toprak ve atmosferik çevrelerini bünyelerinde birleştirdiklerinden sulama programlamasında bitkiyi baz alan su durumu değerlendirmeleri son yıllarda giderek artan bir önem kazanmıştır.
Bitki su durumunun ifade edilmesinde genellikle doku veya organ su potansiyeli (ψ) kullanılmaktadır. Bu potansiyellerin belirlenmesinde termokapl higrometrelerin / psikrometrelerin geniş kullanım alanları vardır.
Tarla koşullarında yaprak su potansiyelinin izlenmesi, teknik ve deneysel olarak bazı problemler içermektedir. Bitki su potansiyelini ölçen birçok standart yöntemler bulunmasına rağmen bu yöntemler uygulama ve zaman yönünden bazı sınırlamalara sahiptir.
Bu makalede, yaprak su potansiyelinin ölçümüne ilişkin temel kavramların açıklanması ve su potansiyelinin tarla koşullarında ölçümüne olanak sağlayan "Çiğlenme Noktası Higrometresi /Psikrometresi" aletinin ayrıntılı olarak gözden geçirilmesi amaçlanmıştır.

Anahtar Kelimeler

Termokapl, Su Potansiyeli, toprak

Measuring of Leaf Water Potential Using Thermocouple Hygrometres/Psychrometres

Öz

Because plants integrate their soil and atmospheric environments, an increasing emphasis on plant based water status evaluation for irrigation scheduling has occurred in recent years.
There are some different parameters to express plant water potential. Most general of these parameters are tissue or organ water potentials (ψ). Thermocouple Hygrometers/Psych- rometers are the most useful instruments for measuring leaf water potentials.
Measuring of the plant water potential at the field conditions includes some problems such as techniques and experiments. In spite there are some methods for measuring plant
water potential these methods are limited in terms of application and time.
In this article, some information will be given about the methods are used for determining plant water potential and the "Dewpoint Hygrometer/Psychrometer" technique for measuring leaf water potential at the field conditions will be explained.

Anahtar Kelimeler

Thermocouple, Water Potential, soil

Kaynakça

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