A Lysimster Study, a Unique Tool for Botanists, Agronomists and Other Plant Scientists

Abstract

A lysimeter is an equipment used to collect and measure soil water that drains below the root zone from a pasture or agriculture field. According to methods of measuring water content, lysimeter devides into weighing lysimeter and non-weighing lysimeter. The weighing lysimeters provide scientists the basic information for research related to evapotranspiration, and they are commonly divided into two types, continous weighing and intermittent weighing. Compared to laboratory experiments, out-door lysimeter studies have advantages like being closer to field environment conditions, it is possible to grow plants and therefore to study the fate of chemicals in soil/plant systems, transformations and leaching. The limitations are costy which depend on design, variable experimental conditions such as environmental/climatic parameters which are normally not controlled, the soil spatial variability is normally less, they are not suitable for every plant species and even every soil type. The objective of lysimeter is defining the crop coefficient (Kc) which used to convert ETr into equivalent crop evapotranpiration (ETc) values, and determing agronomical characteristics of crops which are planted in the field of lysimeter. The duration of a lysimeter study is determined by the objective of the study, but for different crops, it should normally be at least two years. Precipitation should be recorded daily at the lysimeter site. All weather data like air temperature, solar radiation, humidity and potential evporation should be obtained onsite, and the frequency and time of measurements should be at least daily.