Calibration of leaf area index of Larix principis-rupprechtii artificial pure forest in Liupanshan
We conducted this study in the northern part of Liupanshan in Ningxia,China,to improve the plant canopy analyzer accuracy and applicability in measuring the forest leaf area index(LAI).We selected different stand characteristics of North China larch plantations and applied the litter collection method to measure the true LAI of North China larch plantations to determine the plant canopy analyzer error range and calibrate it.Our results indicated the following:(1)the LAI of the artificial pure forest of North China larch in the Liupanshan area was 0-2.96,exhibiting a decreasing trend from August to October;(2)the LAI values measured by the plant canopy analyzer during the mid-growing season(July to September)were relatively small,with an error range of 0.03-0.38(1.41%-15.89%),while the values measured at the end of the growth season(October)were relatively large,with an error range of 0.04-0.86(1.67%-90.87%);and(3)the plant canopy analyzer-generated error measurements were closely related to forest canopy closure,forest density,tree height,diameter at breast height,and other factors.By constructing a multifactor coupling model between forest stand characteristics and LAI,the measurement accuracy and applicability range of the plant canopy analyzer can be improved.
plant canopy analyzerleaf area indexlitter collection methodLarix principis-rupprechtii