Water holding capacity of litter at different slope positions of sand slope in Salix gordejevii sand barrier of Mulan Paddock of northern Hebei Province, northern China

ObjectiveThe differences of litter water holding capacity at different positions with Salix gordejevii sand barrier were studied to provide technical basis for research on vegetation restoration technology of desertified land.

MethodRelative indexes about volume, water retention, water absorption and storage capacity were analyzed through field sampling and indoor measurement.

Result(1) There was no significant difference in litter accumulation and natural moisture content at different slope positions(P>0.05), but the index of correlation about water holding rate and interception amount at different positions showed the trend of middle slope>bottom slope>top slope. And top slope was remarkably less than middle slope and bottom (P < 0.05), and it was minimum for comprehensive index of litter's water holding capacity. Water absorption rate in bottom slope was significantly higher than that of middle slope and top slope(P < 0.01). (2)The water holding capacity and water absorption of litter remained the same with time at different slope positions. Water holding capacity and soaking time of litter were suitable to logarithmic relation and power exponential relation. (3) The water holding capacity of litter was consisted of two major factors, namely, water holding capacity and water absorbing capacity through principal component analysis. Weights were respectively 0.85 and 0.15.

ConclusionIndicators related to the litter's water holding capacity were the primary factors to evaluate the litter water conservation performance. Among them, water holding rate, maximum water holding rate, maximum interception rate, effective interception rate and volume were enough to represent litter's water holding capacity. Middle slope was the largest concerning the indicators and composite indexes of litter's water holding capacity. The middle slope was a key part of the succession. At the local area, Salix gordejevii sand barrier had played a good ecological and hudrological role.