The effects of nano-carbon on soil water infiltration

soil water characteristic curve and soil water distribution were studied by TDR and tensiometer through one dimensional vertical soil column test. The results showed that:(1) With the increasing of infiltration time

the cumulative infiltration amount of the soil contained nano-carbon decreased in the same infiltration time

and the advancing distance of wetting front decreased obviously

and the application of nano-carbon presented obvious infiltration reduction effect. Using Philip infiltration model to fit infiltration data

the infiltration rate S decreased with the increasing of nano-carbon content

meanwhile with the increasing of nano-carbon content

the cumulative infiltration amount decreased gradually in the early stage of water infiltration. The linear fitting of wetting front in different layers showed that infiltration rate decreased significantly when wetting front entered second layers of soil

and nano-carbon layer had obvious effect of water blocking. (2) Adding nano-carbon

the water content of nano-carbon composite layer increased obviously

and soil water content in the lower layer of the nano-carbon composite layer was lower than that in the blank control group. When the nano-carbon content was 0.5%

the soil water content of the nano-carbon composite layer was the maximum. (3) Adding nano-carbon could significantly improve the water holding capacity of soil when the soil was under dehydration condition; the soil water characteristic curves were fitted using the van Genuchten model

and the soil water retention rate(θr)

saturated water content (θs) and the correlation coefficient (α) of the formula significantly increased compared with the soil without nano-carbon

and the shape coefficient n was smaller than that of the soil without nano-carbon.