Phosphates such as total nitrogen, total phosphorus, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen and soluble phosphorus, as well as chemical oxygen demand COD, pH, coliform bacteria and TDS.

The total initial osmotic potential under water saturation, the total osmotic potential at the initial swelling point, and the corresponding relative water content and relative osmotic water content at this point.

Leaf water potential, cell fluid concentration or osmotic potential, stomatal conditions

Biological significance:

Evaluate the ecological risk of soil, predict the changing trend of nutrients such as total nitrogen and total phosphorus, and predict the physiological growth of plants. Reasonable irrigation, improve the soil conditions and climate environment of the cultivation environment, and ensure the good growth of plants.

Determination method:

Heating drying method (including atmospheric oven drying method, vacuum oven drying method, infrared drying method, microwave heating drying method and adding drying additives method)

distillation method

Normal pressure direct drying method