Effects of light intensity variation on nitrogen and phosphorus contents, allocation and limitation in five shade-enduring plants

doi:10.17521/cjpe.2016.0248

Abstract

Abstract:

Aims To enhance the understanding on nitrogen (N) and phosphorus (P) physiological responses to different light environments in shade-enduring plants and provide references to improve the stand structure and ecosystem functions of plantation forests.Methods We selected seedlings of five shade-enduring species with high ecological and economic value in subtropical area of China to study the effects of light intensity on leaf N and P contents, allocation and nutrient limitation in shade-enduring plants. A light intensity gradient of five different levels was set to simulate the varying understory light environment.Important findings With decreasing light intensity, the total biomass and total N and P accumulation of five shade-enduring plants all showed a decreasing trend, but N, P contents in different organs increased. Among them, Gardenia jasminoides (GJ) had the highest while Illicium henryi (IH) had the lowest N content; The P contents of Quercus phillyraeoides (QP) and GJ were significantly higher than Elaeocarpus sylvestris (ES), Ardisia crenata (AC) and IH. QP and GJ had the highest N, P contents under extremely low light intensity (6% natural light intensity) condition (LIC), while AC and IH had the highest N and P contents in low (15% natural light intensity) and moderate (33% and 52% natural light intensity) LIC. ES demanded differently for LIC on N and P, which were 52% and 6% natural light intensity, respectively. N and P allocation of ES, AC and IH followed leaf > root > stem, but for QP and GJ were root > leaf > stem. Decreasing LIC significantly affected N and P allocation. N content variations shown good consistency among different organs under higher LIC (100% natural light intensity) while distinct variability under lower LIC (15% and 6% natural light intensity) in all five species. Phosphorus contents exhibited good consistency in IH, QP and GJ but varied in ES and AC. Decreasing LIC significantly affected organ N/P ratios of shade-enduring plants, but the fundamental growth restriction patterns remained. Light intensity variation and tree species co-regulated N, P utilization and allocation in shade-enduring plants, and then affected the total biomass and total N, P accumulation, which might result from the change of N and P utilization strategy. Therefore, light intensity preference and N, P nutrient balances in shade-enduring plants should be taken into account when constructing multiple layer and uneven-aged forests.

http://jtp.cnki.net/bilingual/detail/html/ZWSB201705008

Key words: light intensity, shade-enduring plant, N content, P content, allocation, adaptation strategy

Hong-Tao XIE, Mu-Kui YU, Xiang-Rong CHENG. Effects of light intensity variation on nitrogen and phosphorus contents, allocation and limitation in five shade-enduring plants[J]. Chin J Plant Ecol, 2017, 41(5): 559-569.

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URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2016.0248

https://www.plant-ecology.com/EN/Y2017/V41/I5/559

Figures/Tables 7

References 36

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物种 Species	缩写 Abbreviation	科属 Family and genera	生活型 Life form	主要用途 Main applications
山杜英 Elaeocarpus sylvestris	ES	杜英科杜英属 Elaeocarpaceae Elaeocarpus	乔木 Tree	园林、木材、防护、药用等 Garden, timber, protection, medicine, etc.
朱砂根 Ardisia crenata	AC	紫金牛科紫金牛属 Myrsinaceae Ardisia	灌木 Shrub	观赏、固土、药用等 Ornamental, soil fixing, medicine, etc.
红茴香 Illicium henryi	IH	八角科八角属 Illiciaceae Illicium	乔木 Tree	观赏、药用等 Ornamental, medicine, etc.
栀子 Gardenia jasminoides	GJ	茜草科栀子属 Rubiaceae Gardenia	灌木 Shrub	园林、食用、药用等 Garden, edible, medicine, etc.
乌冈栎 Quercus phillyraeoides	QP	壳斗科栎属 Fagaceae Quercus	乔木 Tree	木材、酿酒、饲料等 Timber, wine, feed, etc.

物种 Species	缩写 Abbreviation	科属 Family and genera	生活型 Life form	主要用途 Main applications
山杜英 Elaeocarpus sylvestris	ES	杜英科杜英属 Elaeocarpaceae Elaeocarpus	乔木 Tree	园林、木材、防护、药用等 Garden, timber, protection, medicine, etc.
朱砂根 Ardisia crenata	AC	紫金牛科紫金牛属 Myrsinaceae Ardisia	灌木 Shrub	观赏、固土、药用等 Ornamental, soil fixing, medicine, etc.
红茴香 Illicium henryi	IH	八角科八角属 Illiciaceae Illicium	乔木 Tree	观赏、药用等 Ornamental, medicine, etc.
栀子 Gardenia jasminoides	GJ	茜草科栀子属 Rubiaceae Gardenia	灌木 Shrub	园林、食用、药用等 Garden, edible, medicine, etc.
乌冈栎 Quercus phillyraeoides	QP	壳斗科栎属 Fagaceae Quercus	乔木 Tree	木材、酿酒、饲料等 Timber, wine, feed, etc.

物种 Species		相对光强 Relative light intensity
物种 Species		100R	52R	33R	15R	6R
山杜英 Elaeocarpus sylvestris	总N:P Total N:P	9.01 ± 0.59^Cd	15.95 ± 0.53^Aa	16.48 ± 1.19^Aa	14.50 ± 0.29^Ab	10.87 ± 0.38^ABc
	叶片N:P Leaf N:P	15.90 ± 1.19^Aab	18.96 ± 0.59^Aab	19.11 ± 3.11^Aa	17.31 ± 0.45^Aab	15.67 ± 1.79^Bb
	枝干N:P Stem N:P	6.79 ± 0.60^Dc	15.70 ± 0.02^Aa	16.14 ± 0.40^Aa	12.23 ± 0.37^Bb	6.66 ± 0.10^Cc
	根系N:P Root N:P	5.17 ± 1.08^Db	8.72 ± 0.59^Ba	9.31 ± 0.83^Aa	9.39 ± 1.34^Aa	8.28 ± 1.06^Ba
朱砂根 Ardisia crenata	总N:P Total N:P	13.57 ± 0.45^Aa	12.62 ± 0.11^Bb	12.26 ± 0.34^Bbc	12.67 ± 0.41^Bb	11.57 ± 0.47^Ac
	叶片N:P磷 Leaf N:P	16.15 ± 0.71^Ab	16.59 ± 0.48^Bb	17.63 ± 2.80^Bab	16.61 ± 1.17^Ab	19.41 ± 0.11^Aa
	枝干N:P Stem N:P	15.28 ± 1.18^Aa	10.27 ± 0.01^Bb	9.63 ± 0.25^Cbc	8.75 ± 0.44^Ccd	8.28 ± 0.85^Bd
	根系N:P Root N:P	11.61 ± 0.92^Aa	10.26 ± 0.09^Abc	9.64 ± 0.23^Ac	9.58 ± 0.08^Ac	10.58 ± 0.17^Ab
红茴香 Illicium henryi	总N:P Total N:P	10.14 ± 0.73^Ca	8.16 ± 0.28^Da	11.11 ± 0.04^Ca	11.51 ± 0.07^BCa	10.37 ± 0.02^Ba
	叶片N:P Leaf N:P	10.73 ± 1.06^Cb	9.91 ± 0.28^Db	12.24 ± 0.68^Da	12.09 ± 0.05^Ca	11.87 ± 0.40^Ca
	枝干N:P Stem N:P	13.22 ± 1.00^Bab	8.16 ± 0.44^Cc	14.05 ± 0.34^Bab	14.53 ± 1.07^Aa	12.37 ± 1.39^Ab
	根系N:P Root N:P	7.97 ± 0.28^Bb	6.33 ± 0.15^Cd	8.24 ± 0.51^Bb	8.92 ± 0.27^Aa	7.19 ± 0.13^Bc
栀子 Gardenia jasminoides	总N:P Total N:P	12.47 ± 0.24^Ba	10.30 ± 0.15^Cb	11.59 ± 0.91^Ca	9.86 ± 0.42^Cb	11.83 ± 0.29^Aa
	叶片N:P Leaf N:P	15.75 ± 0.51^Aa	14.22 ± 0.34^Cb	15.12 ± 0.91^Cab	15.62 ± 1.26^Bab	16.30 ± 0.48^Ba
	枝干N:P Stem N:P	10.24 ± 0.72^Ca	6.41 ± 0.39^Dc	8.15 ± 0.55^Cb	5.84 ± 0.06^Dcd	5.14 ± 0.09^Dd
	根系N:P Root N:P	7.05 ± 0.15^Ca	5.29 ± 0.01^Ccd	5.88 ± 0.89^Cbc	4.75 ± 0.36^Bd	6.48 ± 0.31^Cab
乌冈栎 Quercus phillyraeoides	总N:P Total N:P	5.38 ± 0.01^Da	5.41 ± 0.04^Ea	4.39 ± 0.04^Db	5.23 ± 0.25^Da	4.54 ± 0.05^Cb
	叶片N:P Leaf N:P	11.64 ± 0.23^Ba	9.84 ± 0.15^Dbc	9.24 ± 0.85^Ec	10.39 ± 0.13^Db	9.92 ± 0.16^Dbc
	枝干N:P Stem N:P	3.65 ± 0.12^Ea	3.32 ± 0.05^Eb	2.98 ± 0.03^Dc	3.57 ± 0.14^Ea	3.59 ± 0.02^Ea
	根系N:P Root N:P	3.82 ± 0.12^Ea	3.52 ± 0.02^Da	2.79 ± 0.37^Db	3.54 ± 0.35^Ca	2.65 ± 0.02^Db

物种 Species		相对光强 Relative light intensity
物种 Species		100R	52R	33R	15R	6R
山杜英 Elaeocarpus sylvestris	总N:P Total N:P	9.01 ± 0.59^Cd	15.95 ± 0.53^Aa	16.48 ± 1.19^Aa	14.50 ± 0.29^Ab	10.87 ± 0.38^ABc
	叶片N:P Leaf N:P	15.90 ± 1.19^Aab	18.96 ± 0.59^Aab	19.11 ± 3.11^Aa	17.31 ± 0.45^Aab	15.67 ± 1.79^Bb
	枝干N:P Stem N:P	6.79 ± 0.60^Dc	15.70 ± 0.02^Aa	16.14 ± 0.40^Aa	12.23 ± 0.37^Bb	6.66 ± 0.10^Cc
	根系N:P Root N:P	5.17 ± 1.08^Db	8.72 ± 0.59^Ba	9.31 ± 0.83^Aa	9.39 ± 1.34^Aa	8.28 ± 1.06^Ba
朱砂根 Ardisia crenata	总N:P Total N:P	13.57 ± 0.45^Aa	12.62 ± 0.11^Bb	12.26 ± 0.34^Bbc	12.67 ± 0.41^Bb	11.57 ± 0.47^Ac
	叶片N:P磷 Leaf N:P	16.15 ± 0.71^Ab	16.59 ± 0.48^Bb	17.63 ± 2.80^Bab	16.61 ± 1.17^Ab	19.41 ± 0.11^Aa
	枝干N:P Stem N:P	15.28 ± 1.18^Aa	10.27 ± 0.01^Bb	9.63 ± 0.25^Cbc	8.75 ± 0.44^Ccd	8.28 ± 0.85^Bd
	根系N:P Root N:P	11.61 ± 0.92^Aa	10.26 ± 0.09^Abc	9.64 ± 0.23^Ac	9.58 ± 0.08^Ac	10.58 ± 0.17^Ab
红茴香 Illicium henryi	总N:P Total N:P	10.14 ± 0.73^Ca	8.16 ± 0.28^Da	11.11 ± 0.04^Ca	11.51 ± 0.07^BCa	10.37 ± 0.02^Ba
	叶片N:P Leaf N:P	10.73 ± 1.06^Cb	9.91 ± 0.28^Db	12.24 ± 0.68^Da	12.09 ± 0.05^Ca	11.87 ± 0.40^Ca
	枝干N:P Stem N:P	13.22 ± 1.00^Bab	8.16 ± 0.44^Cc	14.05 ± 0.34^Bab	14.53 ± 1.07^Aa	12.37 ± 1.39^Ab
	根系N:P Root N:P	7.97 ± 0.28^Bb	6.33 ± 0.15^Cd	8.24 ± 0.51^Bb	8.92 ± 0.27^Aa	7.19 ± 0.13^Bc
栀子 Gardenia jasminoides	总N:P Total N:P	12.47 ± 0.24^Ba	10.30 ± 0.15^Cb	11.59 ± 0.91^Ca	9.86 ± 0.42^Cb	11.83 ± 0.29^Aa
	叶片N:P Leaf N:P	15.75 ± 0.51^Aa	14.22 ± 0.34^Cb	15.12 ± 0.91^Cab	15.62 ± 1.26^Bab	16.30 ± 0.48^Ba
	枝干N:P Stem N:P	10.24 ± 0.72^Ca	6.41 ± 0.39^Dc	8.15 ± 0.55^Cb	5.84 ± 0.06^Dcd	5.14 ± 0.09^Dd
	根系N:P Root N:P	7.05 ± 0.15^Ca	5.29 ± 0.01^Ccd	5.88 ± 0.89^Cbc	4.75 ± 0.36^Bd	6.48 ± 0.31^Cab
乌冈栎 Quercus phillyraeoides	总N:P Total N:P	5.38 ± 0.01^Da	5.41 ± 0.04^Ea	4.39 ± 0.04^Db	5.23 ± 0.25^Da	4.54 ± 0.05^Cb
	叶片N:P Leaf N:P	11.64 ± 0.23^Ba	9.84 ± 0.15^Dbc	9.24 ± 0.85^Ec	10.39 ± 0.13^Db	9.92 ± 0.16^Dbc
	枝干N:P Stem N:P	3.65 ± 0.12^Ea	3.32 ± 0.05^Eb	2.98 ± 0.03^Dc	3.57 ± 0.14^Ea	3.59 ± 0.02^Ea
	根系N:P Root N:P	3.82 ± 0.12^Ea	3.52 ± 0.02^Da	2.79 ± 0.37^Db	3.54 ± 0.35^Ca	2.65 ± 0.02^Db