Study on the Fractal Characteristics of the Plant Root System and Its Relationship with Soil Strength in Tailing Ponds

Table 1

Soil particle distribution under different shrub types.

Sample plot	Soil depth	Gravel (%)	Sand (%)			Silt (%)	Soil clay (%)
	cm	20-2 mm	2-0.5 mm	0.5-0.25 mm	0.25-0.075 mm	0.075-0.005 mm	<0.005 mm
Tailing soil	0~20	0.30^A	6.30^A	13.60^B	69.30^A	6.80^B	3.70^A
	20~40	0.10^A	7.20^B	12.30^B	71.20^A	7.30^A	2.20^A
	40~60	0.30^A	6.50^A	12.50^B	71.20^A	7.30^A	2.20^A
	60~80	0.50^B	5.40^B	13.60^A	73.50^A	4.60^A	2.40^A
	0~80	0.30^A	6.35^B	13.00^A	71.10^A	6.35^A	2.90^A
A. fruticosa plot	0~20	5.60^B	2.30^A	4.60^A	66.20^A	20.70^A	4.60^A
	20~40	0.10^Aa	0.50^Aa	3.30^A	76.10^A	15.80^A	4.20^A
	40~60	0.50^Aa	0.60^B	3.80^A	82.70^Aa	9.20^Aa	3.20^A
	60~80	2.30^Aab	6.10^abc	9.10^Aabc	70.60^A	9.00^Aa	2.90^A
	0~80	2.13^B	2.38^A	5.20^B	72.90^A	13.68^B	3.73^A
H. rhamnoides plot	0~20	0.20^A	3.30^A	5.70^A	66.80^A	16.90^A	7.10^A
	20~40	2.40^Ba	1.30^A	5.60^A	72.30^A	13.60^A	4.80^A
	40~60	0.90^A	5.60^A	7.00^A	68.60^A	13.40^A	4.50^A
	60~80	1.60^A	12.60^Aabc	10.20^A	65.30^A	7.30^A	3.00^A
	0~80	1.28^A	5.70^B	7.13^B	68.25^A	12.80^B	4.85^B

Note (same below): different uppercase letters indicate significant differences in the mechanical composition of soil particles under different shrubs in the same soil section, and different lowercase letters indicate significant differences in the mechanical composition of soil particles under the same shrub in different soil sections ().