Short-term effect of thinning on carbon storage in soil, forest floor and coarse woody debris of Quercus spp. stand in Hoengseong, Gangwon-do, Korea

Figures & data

Table 1. Changes in the characteristics of the study stand after thinning.

Thinning intensity* (%)	Control (0)	Light (15)		Moderate (20)		Heavy (35)
Thinning	–	before	after	before	after	before	after
Stand density (tree ha^−1)	870	902	456	987	748	1,072	743
Mean DBH (cm)	18.4	16.2	17.2	16.4	16.4	15.5	16.8
Mean height (m)	15.7	15.1	15.7	15.8	15.9	13.9	14.9
Basal area (m^2 ha^−1)	27.3	23.2	19.2	23.4	18.1	25.9	18.1
Volume (m^3 ha^−1)	160.8	132.1	111.4	136.1	106.6	136.3	89.7
*Thinning intensity was determined by removal ratio of volume in the study plot.

Figure 1. Soil water content (SWC) (a) and soil pH (b) with different thinning intensities at each soil depth. Figures denoted with different letters indicate significant differences among thinning intensities (P < 0.05). Vertical bars are standard errors.

Table 2. Soil water content (SWC) at each soil depth after thinning. Figures denoted with different letters indicate significant differences among soil depths in each thinning plot (P < 0.05).

Soil depth (cm)	SWC (%)
	Control	Light	Moderate	Heavy
0–10	27.58a	18.56a	31.96a	23.25a
10–20	24.18ab	17.12ab	27.03a	21.26ab
20–30	20.24bc	14.78bc	26.03a	18.29bc
30–50	15.96c	13.22c	23.50a	17.28c

Table 3. Carbon concentration and storage of soil with different thinning intensities at each soil depth. The small letters indicate differences among thinning intensities within the same soil depth, and the large letters indicate differences among soil depths within each plot (P < 0.05). The values in parentheses are standard errors.

Soil depth (cm)	Soil carbon concentration (%)					Soil carbon storage (Mg C ha^−1)
	Control	Light	Moderate	Heavy		Control	Light	Moderate	Heavy
0–10	2.44^aA (0.13)	1.60^cA (0.05)	1.89^bcA (0.10)	2.28^abA (0.23)		14.6^aA (0.77)	12.7^aA (1.26)	13.4^aA (1.64)	17.0^aA (1.51)
10–20	1.28^aB (0.09)	0.75^bB (0.08)	0.87^bB (0.09)	1.27^aB (0.14)		9.2^aB (0.31)	6.0^bB (0.39)	7.7^abB (1.29)	10.2^aB (1.09)
20–30	0.67^abC (0.13)	0.30^bC (0.08)	0.65^abB (0.17)	0.72^aC (0.11)		5.3^aC (0.94)	2.6^aC (0.65)	4.9^aB (1.96)	5.9^aC (0.58)
30–50	0.34^bD (0.04)	0.24^cC (0.02)	0.25^cC (0.03)	0.51^aC (0.02)		4.6^aC (0.81)	4.4^aBC (0.30)	4.4^aB (0.82)	6.2^aC (1.78)
Total	–		–	–		33.7^ab	25.7^c	30.4^bc	39.5^a

Figure 2. Soil bulk density (a) and coarse rock content (b) with different thinning intensities at each soil depth. Figures denoted with different letters indicate significant differences among thinning intensities (P < 0.05). Vertical bars are standard errors.

Table 4. Carbon concentration and storage of forest floor and coarse woody debris (CWD) with different thinning intensities. Figures denoted with different letters indicate significant differences among thinning intensities (P < 0.05). The values in parentheses are standard errors.

Thinning intensity	Forest floor				Coarse woody debris
	Dry weight (Mg ha^−1)	C concentration (%)	C storage (Mg C ha^−1)		Dry weight (Mg ha^−1)	C concentration (%)	C storage (Mg C ha^−1)
Control	9.7b	43.5(1.17)b	4.2b		1.3	48.9	0.6
Light	9.3b	45.8(0.54)ab	4.3b		2.3	47.4	1.1
Moderate	13.8a	45.1(0.70)ab	6.2a		7.2	48.2	4.0
Heavy	10.0b	46.4(0.82)a	4.6ab		2.8	47.9	1.3

Figure 3. Carbon storage (a) and distribution of carbon storage (b) in soil, forest floor and coarse woody debris (CWD) in Quercus spp. stand with different thinning intensities. Figures denoted with different letters indicate significant differences in total C storage among thinning intensities (P < 0.05).