Soil testing. A pH meter showing a neutral pH of soil. Farmers and gardeners use pH meters to determine the pH level of soil to assess its suitability for different plants. A probe placed in the soil measures the amount of free hydrogen ions present,giving a value on the pH scale. A pH of 7 is neutral,above 7 is alkali and below 7 is acid. This meter displays a pH of 6-7,meaning that this is a neutral soil. Some plants are intolerant of acid or alkaline soils,and the pH has to be corrected towards this normal level. For a sequence of pH tests for acid,neutral and alkaline soils,see images E770/1157-1159 | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Terry, Sheila |
Bildgröße: | 4917 px × 4008 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |