Soil Moisture and Nutrient Changes of Agroforestry in Karst Plateau Mountain: A Monitoring Example

To explore soil nutrients and moisture changes in different karst mountain agroforestry, the plateau mountains of Southern China Karst, we used secondary tree irrigation forest (C) as a reference for our study selected four mixed agroforestry species (walnut + maize potato (HYM), walnut (HTY), poplar ryegrass (YSH), (YMH)) comparison. First, change characteristics were monitored situ field. Second, samples, bulk density, porosity, permeability analyzed, nutrient (K, Na, Ca, Mg) tested analyzed. Then, explored relationship between moisture, nutrients, precipitation, nutrients. It is shown (1) during period, variation trends types was small, but it increased/decreased significantly compared with forest, which range more than 5%; (2) water content affected by porosity permeability, HYM, HTY, YSH, YMH correlated permeability; (3) under same precipitation conditions, had lags on regulation, average HYM 0.8 h, HTY 0.6 YSH 0.3 0.4 each type responded at 2–3 h after rain, returned to normal level; (4) fluctuated seasonally, most obvious their Cv value winter summer exceeded 21%. The results provide basic theoretical support further exploring among soil, enrich development areas. They are importance promote ecological restoration