Effects of elevated CO2 concentration and N deposition on leaf element contents of major native tree species in southern subtropical China

doi:10.3724/SP.J.1258.2012.00447

Abstract

Abstract:

Aims The effects of elevated atmospheric CO₂ concentration and N deposition on terrestrial ecosystems and plants are the focus of international ecological study. Changes of nutrient element content in plants induced by atmospheric CO₂ concentration and/or N deposition directly affect the productivity of forest ecosystems; however, few studies have examined this in subtropical China. Our purpose is to study the effects of elevated CO₂ and N deposition on leaf element contents of major native tree species in southern subtropical China.
Methods Five tree species native in southern China were planted in model forest ecosystems. The species were exposed to elevated CO₂ and N deposition in open top chambers in May 2005. The four treatments are: CN (elevated CO₂ and high N deposition), CC (elevated CO₂ and ambient N deposition), NN (high N deposition and ambient CO₂) and CK (ambient CO₂ and ambient N deposition). The elevated CO₂ was (700 ± 20) µmol·mol^-1, and the total amount of added NH₄NO₃-N was 100 kg N·hm^-2·a^-1. Leaves were harvested in January 2009, and elements in the leaves were measured.
Important findings Compared to the control, elevated CO₂ concentration significantly increased leaf-element contents in all species (p < 0.05) except for Ca content in Ormosia pinnata. High N deposition decreased K and Ca contents in the species. There was no interactive effect of high CO₂ concentration and N deposition treatments on most leaf element contents. The interactive effect of high CO₂ concentration and N deposition treatments only decreased leaf Ca contents in Schima superba and Syzygium hancei and leaf Mn contents in Schima superba, Syzygium hancei and Ormosia pinnata, as well as increased leaf P content in trees of Acmena acuminatissima.

Key words: element content, elevated CO₂concentration, N deposition, native tree species

LI Yi-Yong, HUANG Wen-Juan, ZHAO Liang, FANG Xiong, LIU Ju-Xiu. Effects of elevated CO₂ concentration and N deposition on leaf element contents of major native tree species in southern subtropical China[J]. Chin J Plant Ecol, 2012, 36(5): 447-455.

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Figures/Tables 5

References 39

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土壤深度 Soil depth (cm)	pH	K (g·kg^-1)	Na (g·kg^-1)	Ca (g·kg^-1)	Mg (g·kg^-1)	Cu (mg·kg^-1)	Mn (mg·kg^-1)	Zn (mg·kg^-1)	Al (mg·kg^-1)	Pb (mg·kg^-1)	P (g·kg^-1)
0-20	4.15	6.30	0.64	1.03	1.03	4.69	78.70	35.91	1.77	37.48	0.30
0-20	(0.15)	(0.73)	(0.19)	(0.22)	(0.13)	(1.75)	(8.78)	(17.16)	(0.63)	(7.07)	(0.09)
20-40	4.27	5.03	0.63	0.57	0.84	4.68	73.68	30.15	1.55	23.04	0.18
20-40	(0.15)	(1.11)	(0.49)	(0.27)	(0.22)	(1.50)	(25.00)	(14.35)	(0.15)	(6.42)	(0.19)
40-60	4.25	5.49	1.35	0.51	0.83	5.91	65.15	48.02	1.32	19.76	0.14
40-60	(0.13)	(1.53)	(0.63)	(0.18)	(0.23)	(3.60)	(16.96)	(79.07)	(0.19)	(6.61)	(0.07)

土壤深度 Soil depth (cm)	pH	K (g·kg^-1)	Na (g·kg^-1)	Ca (g·kg^-1)	Mg (g·kg^-1)	Cu (mg·kg^-1)	Mn (mg·kg^-1)	Zn (mg·kg^-1)	Al (mg·kg^-1)	Pb (mg·kg^-1)	P (g·kg^-1)
0-20	4.15	6.30	0.64	1.03	1.03	4.69	78.70	35.91	1.77	37.48	0.30
0-20	(0.15)	(0.73)	(0.19)	(0.22)	(0.13)	(1.75)	(8.78)	(17.16)	(0.63)	(7.07)	(0.09)
20-40	4.27	5.03	0.63	0.57	0.84	4.68	73.68	30.15	1.55	23.04	0.18
20-40	(0.15)	(1.11)	(0.49)	(0.27)	(0.22)	(1.50)	(25.00)	(14.35)	(0.15)	(6.42)	(0.19)
40-60	4.25	5.49	1.35	0.51	0.83	5.91	65.15	48.02	1.32	19.76	0.14
40-60	(0.13)	(1.53)	(0.63)	(0.18)	(0.23)	(3.60)	(16.96)	(79.07)	(0.19)	(6.61)	(0.07)

植物 Species	K (g·kg^-1)	Na (g·kg^-1)	Ca (g·kg^-1)	Mg (g·kg^-1)	Cu (mg·kg^-1)	Mn (mg·kg^-1)	Zn (mg·kg^-1)	Al (mg·kg^-1)	Pb (mg·kg^-1)	P (g·kg^-1)
木荷	5.46	1.98	6.81	0.96	4.04	1334.43	29.49	1.89	89.29	0.71
Schima superba	(0.15)	(0.06)	(0.36)	(0.03)	(0.78)	(27.93)	(3.14)	(0.01)	(0.87)	(0.02)
红锥	5.43	2.09	6.55	1.23	4.34	621.86	41.95	1.50	101.12	1.29
Castanopsis hystrix	(0.53)	(0.11)	(0.65)	(0.09)	(0.39)	(53.05)	(6.94)	(0.07)	(17.48)	(0.13)
肖蒲桃	10.51	1.26	7.73	1.32	3.45	36.66	32.69	1.18	44.13	1.29
Acmena acuminatissima	(0.94)	(0.11)	(2.02)	(0.09)	(0.03)	(0.29)	(2.23)	(0.09)	(13.04)	(0.11)
红鳞蒲桃	8.24	0.61	9.42	1.42	5.68	859.61	31.82	1.00	25.94	0.56
Syzygium hancei	(0.56)	(0.05)	(5.83)	(0.14)	(0.63)	(95.30)	(7.99)	(0.00)	(19.03)	(0.02)
海南红豆	7.58	0.56	4.29	0.81	4.56	256.29	28.60	0.96	45.75	1.02
Ormosia pinnata	(0.60)	(0.05)	(0.34)	(0.09)	(0.52)	(19.18)	(3.02)	(0.06)	(12.45)	(0.10)

植物 Species	K (g·kg^-1)	Na (g·kg^-1)	Ca (g·kg^-1)	Mg (g·kg^-1)	Cu (mg·kg^-1)	Mn (mg·kg^-1)	Zn (mg·kg^-1)	Al (mg·kg^-1)	Pb (mg·kg^-1)	P (g·kg^-1)
木荷	5.46	1.98	6.81	0.96	4.04	1334.43	29.49	1.89	89.29	0.71
Schima superba	(0.15)	(0.06)	(0.36)	(0.03)	(0.78)	(27.93)	(3.14)	(0.01)	(0.87)	(0.02)
红锥	5.43	2.09	6.55	1.23	4.34	621.86	41.95	1.50	101.12	1.29
Castanopsis hystrix	(0.53)	(0.11)	(0.65)	(0.09)	(0.39)	(53.05)	(6.94)	(0.07)	(17.48)	(0.13)
肖蒲桃	10.51	1.26	7.73	1.32	3.45	36.66	32.69	1.18	44.13	1.29
Acmena acuminatissima	(0.94)	(0.11)	(2.02)	(0.09)	(0.03)	(0.29)	(2.23)	(0.09)	(13.04)	(0.11)
红鳞蒲桃	8.24	0.61	9.42	1.42	5.68	859.61	31.82	1.00	25.94	0.56
Syzygium hancei	(0.56)	(0.05)	(5.83)	(0.14)	(0.63)	(95.30)	(7.99)	(0.00)	(19.03)	(0.02)
海南红豆	7.58	0.56	4.29	0.81	4.56	256.29	28.60	0.96	45.75	1.02
Ormosia pinnata	(0.60)	(0.05)	(0.34)	(0.09)	(0.52)	(19.18)	(3.02)	(0.06)	(12.45)	(0.10)

	处理 Treatment	K	Na	Ca	Mg	Cu	Mn	Zn	Al	Pb	P
木荷	C	NS	NS	NS	NS	NS	0.005	NS	NS	NS	NS
Schima superba	N	0.008	0.014	NS	0.038	NS	0.000	NS	NS	NS	NS
	C × N	NS	NS	0.016	NS	NS	0.008	NS	NS	NS	NS
红锥	C	0.001	NS	0.010	0.006	0.044	0.000	0.015	NS	0.003	NS
Castanopsis hystrix	N	0.001	0.019	NS	NS	NS	NS	NS	NS	NS	NS
	C × N	NS	NS	NS	NS	NS	NS	NS	NS	NS	NS
肖蒲桃	C	NS	0.007	NS	NS	NS	0.010	NS	0.030	NS	0.000
Acmena acuminatissima	N	NS	0.003	NS	NS	NS	0.008	NS	0.049	NS	0.000
	C × N	NS	NS	NS	NS	NS	NS	NS	NS	NS	0.004
红鳞蒲桃	C	0.004	0.000	NS	0.000	0.016	0.001	0.046	0.003	0.001	0.008
Syzygium hancei	N	NS	0.054	0.005	0.003	NS	NS	NS	NS	NS	NS
	C × N	NS	NS	0.020	0.031	NS	0.002	NS	NS	NS	NS
海南红豆	C	0.009	NS	0.005	NS	NS	0.023	NS	NS	0.060	0.011
Ormosia pinnata	N	0.002	NS	NS	NS	NS	NS	NS	NS	0.008	NS
	C × N	NS	NS	NS	NS	NS	0.029	NS	NS	NS	NS

Effects of elevated CO₂ concentration and N deposition on leaf element contents of major native tree species in southern subtropical China

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