Effects of decay classes and diameter classes on physico-chemical properties of Pinus koraiensis log in a typical mixed broadleaved-Korean pine forest

doi:10.17521/cjpe.2016.0187

Abstract

Abstract: AimsLog is an important component for most of forest ecosystems. It plays crucial roles in maintaining soil fertility, sustaining biodiversity and cycling of carbon (C) and nutrient. However, physico-chemical properties of logs vary with decay classes and diameter classes. Our objective was to study effects of decay classes and diameter classes on physico-chemical properties of logs in a typical mixed broadleaved-Korean pine forest in northern China.MethodsIn this study, logs of Pinus koraiensis were chosen as it was the constructive species in the typical mixed broadleaved-Korean pine forest. Logs of P. koraiensis at each decay classes (I-V) were divided into four diameter classes, including diameter class i ≤ 10.0 cm, diameter class ii: 10.1-30.0 cm, diameter class iii: 30.1-50.0 cm, and diameter class iv > 50.0 cm. Then, we explored effects of different decay classes, diameter classes and their interactions on the physico-chemical properties of logs for both the heartwood and sapwood.Important findings The results showed that the physico-chemical properties of heartwood and sapwood generally exhibited similar variations. Their moisture content both increased with an increasing decay class, whereas wood density both decreased with an increased decay class and diameter class. The carbon concentrations of the sapwood showed a trend of gradual increasing during decomposition, and there was an accumulation in nitrogen (N) and phosphorus (P) concentrations of the heartwood and sapwood with an increased decay class, simultaneously. Only N and P concentrations of the heartwood increased and then decreased with an increasing diameter class. The cellulose content decreased with an increasing decay class. In contrast to the cellulose, the lignin content increased with an increased decay class. However, cellulose and lignin contents exhibited no distinct trend among diameter classes. The moisture content of logs had a significant positive correlation with C, N, P concentrations and lignin content (except P concentrations of the heartwood), but had a significant negative correlation with the cellulose content (p< 0.05). The wood density was negatively correlated with C, N, P concentrations and the lignin content, but it was positively correlated with the cellulose content (p< 0.05). Therefore, physico-chemical properties of logs had unique patterns along both decay classes and diameter classes, and the physical properties of logs (the moisture content and wood density) were important factor affecting the variations of their chemical contents.

http://jtp.cnki.net/bilingual/detail/html/ZWSB201612007

Key words: mixed broadleaved-Korean pine forest, log, decay class, diameter class, physico-chemical pro- perties

Yu ZHANG, Guang-Ze JIN. Effects of decay classes and diameter classes on physico-chemical properties of Pinus koraiensis log in a typical mixed broadleaved-Korean pine forest[J]. Chin J Plant Ecol, 2016, 40(12): 1276-1288.

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URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2016.0187

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因子 Factor	组分 Component	含水率 Moisture content	木材密度 Wood density	碳含量 Carbon content	氮含量 Nitrogen content	磷含量 Phosphorus content	纤维素含量 Cellulose content	木质素含量 Lignin content
腐烂等级	心材 Heartwood	p < 0.001	p < 0.001	p > 0.05	p = 0.024	p = 0.009	p < 0.001	p < 0.001
Decay class	边材 Sapwood	p < 0.001	p < 0.001	p = 0.012	p = 0.003	p < 0.001	p < 0.001	p < 0.001
径级	心材 Heartwood	p > 0.05	p = 0.003	p > 0.05	p = 0.002	p < 0.001	p > 0.05	p > 0.05
Diameter class	边材 Sapwood	p > 0.05	p = 0.045	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p > 0.05
腐烂等级×径级	心材 Heartwood	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p = 0.019	p = 0.044
Decay class × diameter class	边材 Sapwood	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p = 0.014	p = 0.016

因子 Factor	组分 Component	含水率 Moisture content	木材密度 Wood density	碳含量 Carbon content	氮含量 Nitrogen content	磷含量 Phosphorus content	纤维素含量 Cellulose content	木质素含量 Lignin content
腐烂等级	心材 Heartwood	p < 0.001	p < 0.001	p > 0.05	p = 0.024	p = 0.009	p < 0.001	p < 0.001
Decay class	边材 Sapwood	p < 0.001	p < 0.001	p = 0.012	p = 0.003	p < 0.001	p < 0.001	p < 0.001
径级	心材 Heartwood	p > 0.05	p = 0.003	p > 0.05	p = 0.002	p < 0.001	p > 0.05	p > 0.05
Diameter class	边材 Sapwood	p > 0.05	p = 0.045	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p > 0.05
腐烂等级×径级	心材 Heartwood	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p = 0.019	p = 0.044
Decay class × diameter class	边材 Sapwood	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p > 0.05	p = 0.014	p = 0.016

	组分 Component	腐烂等级 Decay class					Total
	组分 Component	I	II	III	IV	V	Total
C:N	心材 Heartwood	467 ± 68^aA	317 ± 28^abA	333 ± 83^abA	264 ± 30^bA	275 ± 29^bA	336 ± 27^A
	边材 Sapwood	432 ± 88^aA	288 ± 29^abA	240 ± 41^bA	177 ± 25^bA	178 ± 18^bA	269 ± 25^A
C:P	心材 Heartwood	8 916 ± 5 783^aA	9 667 ± 1 548^aA	4 952 ± 1 181^aA	3 135 ± 619^aA	3 970 ± 1 227^aA	6 220 ± 1 324^A
C:P	边材 Sapwood	6 998 ± 1 153^bA	23 209 ± 8 640^aA	3 541 ± 725^bA	1 621 ± 251^bB	1 621 ± 244^bB	7 423 ± 1 964^A
N:P	心材 Heartwood	22 ± 12.28^aA	31 ± 4.31^aA	20 ± 5.21^aA	18 ± 7.48^aA	15 ± 5.09^aA	21 ± 3.37^A
	边材 Sapwood	21 ± 3.32^bA	88 ± 31.54^aA	23 ± 7.71^bA	10 ± 1.32^bA	10 ± 1.5^bA	30 ± 7.27^A
木质素:纤维素	心材 Heartwood	0.91 ± 0.26^bA	0.89 ± 0.19^bA	1.44 ± 0.03^bA	1.90 ± 0.40^bA	3.22 ± 0.63^aA	1.67 ± 0.20^A
Lignin:cellulose	边材 Sapwood	0.56 ± 0.06^cA	0.65 ± 0.05^cA	1.07 ± 0.17^bcA	1.70 ± 0.22^bA	2.71 ± 0.50^aA	1.34 ± 0.15^A

	组分 Component	腐烂等级 Decay class					Total
	组分 Component	I	II	III	IV	V	Total
C:N	心材 Heartwood	467 ± 68^aA	317 ± 28^abA	333 ± 83^abA	264 ± 30^bA	275 ± 29^bA	336 ± 27^A
	边材 Sapwood	432 ± 88^aA	288 ± 29^abA	240 ± 41^bA	177 ± 25^bA	178 ± 18^bA	269 ± 25^A
C:P	心材 Heartwood	8 916 ± 5 783^aA	9 667 ± 1 548^aA	4 952 ± 1 181^aA	3 135 ± 619^aA	3 970 ± 1 227^aA	6 220 ± 1 324^A
C:P	边材 Sapwood	6 998 ± 1 153^bA	23 209 ± 8 640^aA	3 541 ± 725^bA	1 621 ± 251^bB	1 621 ± 244^bB	7 423 ± 1 964^A
N:P	心材 Heartwood	22 ± 12.28^aA	31 ± 4.31^aA	20 ± 5.21^aA	18 ± 7.48^aA	15 ± 5.09^aA	21 ± 3.37^A
	边材 Sapwood	21 ± 3.32^bA	88 ± 31.54^aA	23 ± 7.71^bA	10 ± 1.32^bA	10 ± 1.5^bA	30 ± 7.27^A
木质素:纤维素	心材 Heartwood	0.91 ± 0.26^bA	0.89 ± 0.19^bA	1.44 ± 0.03^bA	1.90 ± 0.40^bA	3.22 ± 0.63^aA	1.67 ± 0.20^A
Lignin:cellulose	边材 Sapwood	0.56 ± 0.06^cA	0.65 ± 0.05^cA	1.07 ± 0.17^bcA	1.70 ± 0.22^bA	2.71 ± 0.50^aA	1.34 ± 0.15^A

	组分 Component	径级 Diameter class				Total
	组分 Component	ⅰ	ⅱ	ⅲ	ⅳ	Total
C:N	心材 Heartwood	492 ± 69^aA	276 ± 23^bA	214 ± 23^bA	355 ± 57^abA	336 ± 27^A
C:N	边材 Sapwood	388 ± 92^aA	266 ± 27^abA	199 ± 30^bA	243 ± 38^abA	269 ± 25^A
C:P	心材 Heartwood	12 672 ± 5 284^aA	6 320 ± 1 107^abA	2 853 ± 765^bA	3 788 ± 607^bA	6 220 ± 1 324^A
	边材 Sapwood	19 255 ± 7 772^aA	3 277 ± 514^bB	4 240 ± 1 165^bA	3 790 ± 973^bA	7 423 ± 1 964^A
N:P	心材 Heartwood	29 ± 11.19^aA	29 ± 6.74^aA	14 ± 3.79^aA	15 ± 3.19^aA	21 ± 3.37^A
	边材 Sapwood	69 ± 28.81^aA	17 ± 5.89^bA	19 ± 3.72^bA	19 ± 4.32^bA	30 ± 7.27^A
木质素:纤维素	心材 Heartwood	2.03 ± 0.65^aA	1.20 ± 0.20^aA	2.01 ± 0.37^aA	1.44 ± 0.22^aA	1.67 ± 0.20^A
Lignin:cellulose	边材 Sapwood	1.74 ± 0.48^aA	1.18 ± 0.18^aA	1.33 ± 0.24^aA	1.13 ± 0.21^aA	1.34 ± 0.15^A