Effects of nitrogen addition on leaf traits of common species in natural Pinus tabuliformis forests in Taiyue Mountain, Shanxi Province, China

doi:10.17521/cjpe.2015.1043

Abstract

Abstract:

Aims Our objectives were to explore the effects of simulated nitrogen deposition on leaf traits and ecological stoichiometry characteristics of common species in natural Pinus tabuliformis forests.
Methods We conducted the experiment of nitrogen (N) addition from 2009 to 2013 in the natural Pinus tabuliformis forests in Taiyue Mountain, Shanxi, China. The levels of N addition were 0 (control), 50 (low-N), 100 (medium-N) and 150 (high-N) kg·hm^-2·a^-1, respectively. Eleven common plant species in 12 20 m × 20 m plots were selected, including Pinus tabuliformis, Quercus mongolica, Acer ginnala, Corylus mandshurica, Cornus bretschneideri, Spiraea salicifolia, Lonicera maackii, Carex callitrichos, Diarrhena mandshurica, Anemone tomentosa, and Polygonatum odoratum. Nine leaf traits were measured, including leaf thickness (LT), specific leaf area (SLA), leaf dry matter content (LDMC), leaf nitrogen content (LNC), leaf phosphorus content (LPC), and other four.
Important findings We found that: 1) LT and SLA of Polygonatum odoratum significantly differed among four levels of N addition. Leaf area (LA) and LDMC of several species, such as Spiraea salicifolia, had significant difference among the N addition concentration. LNC of all species, chlorophyll content (CC) and LPC of most species increased significantly with the addition of N. Leaf N:P of 9 species varied significantly, and leaves with different types and ages showed different responses to N addition. 2) Leaf traits were significantly correlated with each other. For instance, SLA was significantly positively correlated with LNC and LPC. In contrast LT was negatively connected with LNC and LPC. In addition, the degree of correlation changed with the level of N addition. 3) The pattern of species distribution in leaf trait space was consistent with the prediction from the theory of Leaf Economic Spectrum (LES). N addition drove species moving along axis 1 in the trait space, and propelled them towards different directions along axis 2, which indicated that these species tended to take the “fast investment-return” strategy. These results suggested that with the change of environmental conditions, plants changed their survival strategy and adjusted resource allocation to maintain the stability of communities. This is the inherent characteristic of plants, thus the formation of LES did not depend on the environment change.

http://jtp.cnki.net/bilingual/detail/html/ZWSB201607005

Key words: atmospheric nitrogen deposition, leaf economic spectrum, leaf functional traits, natural Pinus tabuliformis forest, nitrogen addition

Di XIAO, Xiao-Jie WANG, Kai ZHANG, Nian-Peng HE, Ji-Hua HOU. Effects of nitrogen addition on leaf traits of common species in natural Pinus tabuliformis forests in Taiyue Mountain, Shanxi Province, China[J]. Chin J Plant Ecol, 2016, 40(7): 686-701.

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Figures/Tables 9

References 79

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处理 Treatment	林分特征 Stand characteristics						土壤理化性质 Physical-chemical properties of soil
	林龄 Stand age (a)	密度 Density (plant·hm^-2)	平均胸径 Mean diameter at breast height (cm)	平均株高 Mean plant height (m)	坡度 Slope (°)		土壤容重 Soil volume weight (g·cm^-3)	土壤pH Soil pH	土壤有机碳含量 Soil organic carbon content (mg·g^-1)	土壤氮含量 Soil nitrogen content (mg·g^-1)	土壤磷含量 Soil phosphorus content (mg·g^-1)
	对照 Control	75	1 267	23.9	17.7	24		0.94	7.12	45.30	1.70	0.43
低氮 Low-N	75	1 567	20.6	17.8	21		0.97	7.12	61.02	2.14	0.38
中氮 Medium-N	75	1 208	23.5	17.4	25		1.07	7.19	42.14	1.91	0.38
高氮 High-N	75	1 225	23.4	19	23		1.06	7.28	36.08	2.25	0.44

处理 Treatment	林分特征 Stand characteristics						土壤理化性质 Physical-chemical properties of soil
	林龄 Stand age (a)	密度 Density (plant·hm^-2)	平均胸径 Mean diameter at breast height (cm)	平均株高 Mean plant height (m)	坡度 Slope (°)		土壤容重 Soil volume weight (g·cm^-3)	土壤pH Soil pH	土壤有机碳含量 Soil organic carbon content (mg·g^-1)	土壤氮含量 Soil nitrogen content (mg·g^-1)	土壤磷含量 Soil phosphorus content (mg·g^-1)
	对照 Control	75	1 267	23.9	17.7	24		0.94	7.12	45.30	1.70	0.43
低氮 Low-N	75	1 567	20.6	17.8	21		0.97	7.12	61.02	2.14	0.38
中氮 Medium-N	75	1 208	23.5	17.4	25		1.07	7.19	42.14	1.91	0.38
高氮 High-N	75	1 225	23.4	19	23		1.06	7.28	36.08	2.25	0.44

叶性状 Leaf trait	处理 Treatment	生活型 Life form
叶性状 Leaf trait	处理 Treatment	针叶乔木 Coniferous tree	阔叶乔木 Broadleaf tree	灌木 Shrub	草本 Herb
叶厚度 Leaf thickness (μm)	CK LN MN HN	716.23 ± 15.16^a 675.67 ± 27.71^a 689.33 ± 27.24^a 661.00 ± 17.85^a	160.45 ± 10.44^a 136.88 ± 10.45^a 147.48 ± 5.23^a 154.85 ± 9.76^a	167.45 ± 18.16^a 166.78 ± 13.89^a 152.16 ± 7.41^a 167.69 ± 16.35^a	199.43 ± 28.20^a 198.07 ± 23.30^a 168.19 ± 20.76^a 161.35 ± 17.11^a
叶面积 Leaf area (cm²)	CK LN MN HN	6.59 ± 0.14^ab 7.13 ± 0.33^a 7.18 ± 0.01^a 6.45 ± 0.12^b	22.91 ± 2.70^a 23.92 ± 4.38^a 29.33 ± 4.91^a 26.49 ± 3.74^a	25.59 ± 5.56^a 23.79 ± 4.83^a 25.97 ± 5.02^a 30.02 ± 5.96^a	39.75 ± 12.70^a 39.36 ± 12.85^a 44.70 ± 13.22^a 51.44 ± 20.18^a
比叶面积 Specific leaf area (m²·kg^-1)	CK LN MN HN	12.42 ± 0.53^a 12.62 ± 0.33^a 11.54 ± 0.40^a 12.67 ± 0.79^a	24.32 ± 1.36^ab 25.95 ± 0.91^a 22.19 ± 1.43^ab 21.73 ± 1.19^b	36.06 ± 0.86^a 35.15 ± 1.27^a 32.66 ± 1.69^a 32.00 ± 1.56^a	34.22 ± 1.12^a 33.30 ± 0.92^a 32.98 ± 1.16^a 31.60 ± 1.09^a
叶绿素含量 Chlorophyll content (SPAD)	CK LN MN HN	45.73 ± 1.36^a 40.37 ± 1.34^a 44.03 ± 1.95^a 42.23 ± 2.87^a	43.78 ± 1.91^b 46.87 ± 2.17^ab 48.75 ± 1.82^ab 49.47 ± 1.21^a	35.20± 1.46^a 37.03 ± 1.60^a 39.65 ± 1.83^a 39.71 ± 1.83^a	30.78 ± 1.50^a 31.81 ± 1.74^a 34.86 ± 1.47^a 33.62 ± 1.43^a
叶干物质含量 Leaf dry matter content (g·kg^-1)	CK LN MN HN	391.87 ± 5.43^b 421.10 ± 7.77^a 420.03 ± 3.91^a 416.17 ± 7.31^a	381.12 ± 15.37^a 377.22 ± 3.14^a 395.85 ± 11.58^a 384.52 ± 5.94^a	284.66 ± 12.41^a 287.51 ± 11.45^a 290.32 ± 15.77^a 295.34 ± 11.52^a	236.01 ± 16.81^a 241.20 ± 16.62^a 213.13 ± 23.40^a 249.49 ± 11.31^a
叶有机碳含量 Leaf carbon content (mg·g^-1)	CK LN MN HN	587.59 ± 10.05^a 541.67 ± 27.75^a 553.05 ± 1.01^a 548.83 ± 4.88^a	473.87 ± 15.47^a 486.62 ± 17.09^a 481.64 ± 13.02^a 487.60 ± 13.23^a	484.68 ± 17.84^a 450.92 ± 7.49^a 454.37 ± 6.12^a 468.28 ± 11.67^a	452.51 ± 7.97^a 441.45 ± 8.30^a 449.41 ± 9.61^a 450.11 ± 6.43^a
叶氮含量 Leaf nitrogen content (mg·g^-1)	CK LN MN HN	12.09 ± 0.39^b 13.48 ± 0.47^a 11.91 ± 0.50^b 12.50 ± 0.38^ab	25.25 ± 0.79^Cc 26.60 ± 0.32^BCb 27.56 ± 0.47^Bb 29.78 ± 0.37^Aa	22.47 ± 0.61^Bc 25.63 ± 0.56^Ab 25.81 ± 0.47^Ab 26.93 ± 0.45^Aa	22.96 ± 0.75^Cc 28.04 ± 0.80^Bb 28.20 ± 0.62^Bb 30.47 ± 0.74^Aa
叶磷含量 Leaf phosphorus content (mg·g^-1)	CK LN MN HN	1.08 ± 0.12^a 1.02 ± 0.10^a 1.06 ± 0.11^a 0.98 ± 0.07^a	1.60 ± 0.11^ABb 1.48 ± 0.05^Bb 1.70 ± 0.07^ABab 1.92 ± 0.17^Aa	1.17 ± 0.05^Cc 1.41 ± 0.03^Bb 1.71 ± 0.07^Aa 1.75 ± 0.05^Aa	1.26 ± 0.04^Bc 1.68 ± 0.08^Ab 1.91 ± 0.08^Aa 1.86 ± 0.08^Aab
叶氮磷比 leaf N:P	CK LN MN HN	12.54 ± 1.11^a 14.75 ± 1.14^a 12.44 ± 0.89^a 14.40 ± 0.80^a	16.39 ± 0.96^a 18.16 ± 0.46^a 16.44 ± 0.52^a 16.70 ± 1.08^a	19.86 ± 0.89^Aa 18.47 ± 0.61^ABa 15.80 ± 0.72^Bb 15.77 ± 0.59^Bb	18.50 ± 0.50^Aa 17.26 ± 0.66^ABab 15.16 ± 0.44^Bc 16.95 ± 0.59^ABb

叶性状 Leaf trait	处理 Treatment	生活型 Life form
叶性状 Leaf trait	处理 Treatment	针叶乔木 Coniferous tree	阔叶乔木 Broadleaf tree	灌木 Shrub	草本 Herb
叶厚度 Leaf thickness (μm)	CK LN MN HN	716.23 ± 15.16^a 675.67 ± 27.71^a 689.33 ± 27.24^a 661.00 ± 17.85^a	160.45 ± 10.44^a 136.88 ± 10.45^a 147.48 ± 5.23^a 154.85 ± 9.76^a	167.45 ± 18.16^a 166.78 ± 13.89^a 152.16 ± 7.41^a 167.69 ± 16.35^a	199.43 ± 28.20^a 198.07 ± 23.30^a 168.19 ± 20.76^a 161.35 ± 17.11^a
叶面积 Leaf area (cm²)	CK LN MN HN	6.59 ± 0.14^ab 7.13 ± 0.33^a 7.18 ± 0.01^a 6.45 ± 0.12^b	22.91 ± 2.70^a 23.92 ± 4.38^a 29.33 ± 4.91^a 26.49 ± 3.74^a	25.59 ± 5.56^a 23.79 ± 4.83^a 25.97 ± 5.02^a 30.02 ± 5.96^a	39.75 ± 12.70^a 39.36 ± 12.85^a 44.70 ± 13.22^a 51.44 ± 20.18^a
比叶面积 Specific leaf area (m²·kg^-1)	CK LN MN HN	12.42 ± 0.53^a 12.62 ± 0.33^a 11.54 ± 0.40^a 12.67 ± 0.79^a	24.32 ± 1.36^ab 25.95 ± 0.91^a 22.19 ± 1.43^ab 21.73 ± 1.19^b	36.06 ± 0.86^a 35.15 ± 1.27^a 32.66 ± 1.69^a 32.00 ± 1.56^a	34.22 ± 1.12^a 33.30 ± 0.92^a 32.98 ± 1.16^a 31.60 ± 1.09^a
叶绿素含量 Chlorophyll content (SPAD)	CK LN MN HN	45.73 ± 1.36^a 40.37 ± 1.34^a 44.03 ± 1.95^a 42.23 ± 2.87^a	43.78 ± 1.91^b 46.87 ± 2.17^ab 48.75 ± 1.82^ab 49.47 ± 1.21^a	35.20± 1.46^a 37.03 ± 1.60^a 39.65 ± 1.83^a 39.71 ± 1.83^a	30.78 ± 1.50^a 31.81 ± 1.74^a 34.86 ± 1.47^a 33.62 ± 1.43^a
叶干物质含量 Leaf dry matter content (g·kg^-1)	CK LN MN HN	391.87 ± 5.43^b 421.10 ± 7.77^a 420.03 ± 3.91^a 416.17 ± 7.31^a	381.12 ± 15.37^a 377.22 ± 3.14^a 395.85 ± 11.58^a 384.52 ± 5.94^a	284.66 ± 12.41^a 287.51 ± 11.45^a 290.32 ± 15.77^a 295.34 ± 11.52^a	236.01 ± 16.81^a 241.20 ± 16.62^a 213.13 ± 23.40^a 249.49 ± 11.31^a
叶有机碳含量 Leaf carbon content (mg·g^-1)	CK LN MN HN	587.59 ± 10.05^a 541.67 ± 27.75^a 553.05 ± 1.01^a 548.83 ± 4.88^a	473.87 ± 15.47^a 486.62 ± 17.09^a 481.64 ± 13.02^a 487.60 ± 13.23^a	484.68 ± 17.84^a 450.92 ± 7.49^a 454.37 ± 6.12^a 468.28 ± 11.67^a	452.51 ± 7.97^a 441.45 ± 8.30^a 449.41 ± 9.61^a 450.11 ± 6.43^a
叶氮含量 Leaf nitrogen content (mg·g^-1)	CK LN MN HN	12.09 ± 0.39^b 13.48 ± 0.47^a 11.91 ± 0.50^b 12.50 ± 0.38^ab	25.25 ± 0.79^Cc 26.60 ± 0.32^BCb 27.56 ± 0.47^Bb 29.78 ± 0.37^Aa	22.47 ± 0.61^Bc 25.63 ± 0.56^Ab 25.81 ± 0.47^Ab 26.93 ± 0.45^Aa	22.96 ± 0.75^Cc 28.04 ± 0.80^Bb 28.20 ± 0.62^Bb 30.47 ± 0.74^Aa
叶磷含量 Leaf phosphorus content (mg·g^-1)	CK LN MN HN	1.08 ± 0.12^a 1.02 ± 0.10^a 1.06 ± 0.11^a 0.98 ± 0.07^a	1.60 ± 0.11^ABb 1.48 ± 0.05^Bb 1.70 ± 0.07^ABab 1.92 ± 0.17^Aa	1.17 ± 0.05^Cc 1.41 ± 0.03^Bb 1.71 ± 0.07^Aa 1.75 ± 0.05^Aa	1.26 ± 0.04^Bc 1.68 ± 0.08^Ab 1.91 ± 0.08^Aa 1.86 ± 0.08^Aab
叶氮磷比 leaf N:P	CK LN MN HN	12.54 ± 1.11^a 14.75 ± 1.14^a 12.44 ± 0.89^a 14.40 ± 0.80^a	16.39 ± 0.96^a 18.16 ± 0.46^a 16.44 ± 0.52^a 16.70 ± 1.08^a	19.86 ± 0.89^Aa 18.47 ± 0.61^ABa 15.80 ± 0.72^Bb 15.77 ± 0.59^Bb	18.50 ± 0.50^Aa 17.26 ± 0.66^ABab 15.16 ± 0.44^Bc 16.95 ± 0.59^ABb

	LT	LA	SLA	CC	LDMC	LCC	LNC	LPC	N:P	N-Tr.	Sp.	Sig. (N-Tr.× Sp.)
LT	1									-0.06	-0.50^**	0.00
LA	-0.17^**	1								0.06	0.37^**	0.00
SLA	-0.73^**	0.42^**	1							-0.12^*	0.71^**	0.01
CC	0.10	0.25^**	-0.34^**	1						0.18^**	-0.30^**	0.00
LDMC	0.11	-0.43^**	-0.56^**	0.35^**	1					0.04	-0.72^**	0.00
LCC	0.44^**	-0.55^**	-0.64^**	0.22^**	0.52^**	1				-0.04	-0.58^**	0.00
LNC	-0.73^**	0.56^**	0.71^**	0.13^*	-0.37^**	-0.60^**	1			0.25^**	0.62^**	0.00
LPC	-0.46^**	0.42^**	0.50^**	0.03	-0.40^**	-0.54^**	0.71^**	1		0.34^**	0.39^**	0.00
N:P	-0.36^**	0.17^**	0.29^**	0.14^*	0.08	-0.06	0.29^**	-0.41^**	1	-0.17^**	0.26^**	0.00