Potassium lebanese soils as reflected by electro-ultrafiltration,chemical extraction and cropping

Available zinc status of lebanese soils

Soil carbon and nitrogen changes as influenced by tillage and cropping systems in some Iowa soils

Soil organic C (SOC) and total N (TN) contents play a crucial role in sustaining agricultural production systems. Short-term ( 10-year) management effects on SOC and TN dynamics are often complex and variable. Three experiments were conducted to evaluate short-term tillage and cropping system effects on SOC and TN within the 0–30 cm soil depth across Iowa. The first experiment with no-tillage a...

Low-Input Cropping for Acid Soils

A low-input cropping system has been developed at Yurimiaguas, Peru, to serve as a transition technology between shifting and continuous cultivation for acid soiln of the humid tropics. Principal features are slash-andburn clearing, rotation of acid-tolerant upland rice and cowpea cultivars, maximum residue return, no tillage, and no lime or fertilizer apoiications. When yields decline as a res...

Fixation of Potassium in Soils.

That some of the potassium added in the form of fertilizers or otherwise becomes fixed in the soil had been known for a long time. With the clarification of the phenomena of base exchange in soils by Gedroiz it was revealed that the K-ion is fixed in the exchange complex not only in replaceable but also in non-replaceable form. A review of the work in this connection may be found in the paper b...

A new grading system for plant-available potassium using exhaustive cropping techniques combined with chemical analyses of soils

A new grading system for plant-available potassium (K) in soils based on K release rate from soils and plant growth indices was established. In the study, fourteen different agricultural soils from the southern subtropical to the northern temperate zones in China were analyzed by both chemical extraction methods and exhaustive cropping techniques. Based on the change trends in plant growth indi...

Changes in Different Forms of Potassium and Clay Minerals in Soils as Influenced by Different Aged Orange Trees (Citrus sinensis) in Darab, Fars Province

Despite the great importance of potassium applied as a fertilizer in the orange orchards, no information is currently available regarding the rate of potassium release from rhizosphere and the bulk soils of such trees. The objectives of this study were to investigate the weathering of micaceous minerals and their non-exchangeable K release and also, to examine the status of different forms of K...