Biomass allocation and leaf stoichiometric characteristics in four desert herbaceous plants during different growth periods in the Gurbantünggüt Desert, China

doi:10.3724/SP.J.1258.2014.00087

Abstract

Abstract:

Aims Plant biomass allocation and elemental homeostasis have recently become a focus in ecological studies. Herbaceous plants are a major component of species diversity in desert ecosystems. Study on biomass allocation and leaf stoichiometry with growth will be beneficial to further understanding the survival strategy and functional features of desert herbs.
Methods Four dominant species, including two ephemeral plants (Erodium oxyrrhynchum and Hyalea pulchella) and two annals (Agriophyllum squarrosum and Ceratocarpus arenarius), were selected for in situ and multiple- time investigations. Changes in the characteristics of biomass allocation and leaf N-P stoichiometry, as well as their relationships were analyzed.
Important findings Root to shoot ratio decreased gradually during the accumulation of plant biomass in all the four species. The allometric relationships between above- and belowground biomass, however, varied among the four species; the allometric scaling exponents in H. pulchella and C. arenarius initially increased and then decreased, and tended to become stable toward the later period, whereas the allometric scaling exponents in E. oxyrrhynchum and A. squarrosum initially increased and then tended to be isometry in later period. The leaf N and P contents tended to increase in H. pulchella, but declined in other three species with growth, indicating that the leaf N-P stoichiometry of the plants studied changed and showed weak correlations with biomass indices.

Key words: allometric relationship, annals, biomass allocation, ecological stoichiometry, ephemeral plant, Gurbantünggüt Desert

XIAO Yao,TAO Ye,ZHANG Yuan-Ming. Biomass allocation and leaf stoichiometric characteristics in four desert herbaceous plants during different growth periods in the Gurbantünggüt Desert, China[J]. Chin J Plant Ecol, 2014, 38(9): 929-940.

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Figures/Tables 9

References 45

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物种 Species	生长期 Growth period	样本量 No. of samples	地上生物量 Aboveground biomass (g)	地下生物量 Belowground biomass (g)	总生物量 Total biomass (g)
琉苞菊 Hyalea pulchella	April 18	33	0.026 4 ± 0.003 7^a	0.007 7 ± 0.000 7^a	0.034 1 ± 0.004 3^a
	April 28	35	0.094 4 ± 0.006 8^ab	0.010 2 ± 0.000 7^a	0.104 6 ± 0.007 2^ab
	May 8	33	0.212 4 ± 0.016 4^ab	0.031 0 ± 0.003 3^b	0.243 4 ± 0.019 4^ab
	May 18	40	0.328 0 ± 0.023 2^b	0.055 4 ± 0.003 9^c	0.383 3 ± 0.026 8^b
	May 31	40	1.431 0 ± 0.179 8^c	0.145 9 ± 0.014 2^d	1.577 0 ± 0.192 8^c
尖喙牻牛儿苗 Erodium oxyrrhynchum	April 28	35	0.018 4 ± 0.001 4^a	0.004 9 ± 0.000 3^a	0.023 3 ± 0.001 6^a
	May 8	40	0.051 3 ± 0.004 7^a	0.010 8 ± 0.000 9^b	0.062 1 ± 0.005 4^a
	May 18	40	0.113 6 ± 0.008 6^b	0.025 1 ± 0.002 1^c	0.138 7 ± 0.010 6^b
	May 31	36	0.265 4 ± 0.011 3^c	0.024 3 ± 0.003 0^c	0.289 7 ± 0.012 3^c
角果藜 Ceratocarpus arenarius	April 28	29	0.009 1 ± 0.001 0^a	0.001 9 ± 0.000 1^a	0.010 9 ± 0.001 1^a
	May 8	40	0.017 8 ± 0.001 4^a	0.003 9 ± 0.000 3^a	0.021 7 ± 0.001 7^a
	May 18	40	0.068 3 ± 0.004 9^ab	0.009 8 ± 0.000 7^a	0.078 1 ± 0.005 4^ab
	May 31	40	0.152 7 ± 0.016 4^b	0.018 5 ± 0.001 6^b	0.171 1 ± 0.017 8^b
	June 10	40	0.407 3 ± 0.044 3^c	0.037 1 ± 0.003 2^c	0.444 4 ± 0.047 4^c
	June 27	32	1.215 0 ± 0.100 9^d	0.091 5 ± 0.006 6^d	1.307 0 ± 0.106 4^d
沙蓬 Agriophyllum squarrosum	May 8	38	0.027 7 ± 0.002 5^a	0.005 8 ± 0.000 3^a	0.033 4 ± 0.002 8^a
	May 18	40	0.125 2 ± 0.010 0^a	0.019 9 ± 0.001 5^a	0.145 1 ± 0.011 4^a
	May 31	40	0.587 3 ± 0.054 0^a	0.091 2 ± 0.008 0^ab	0.678 5 ± 0.061 4^a
	June 10	17	2.364 0 ± 0.320 3^b	0.254 6 ± 0.032 3^b	2.618 0 ± 0.351 2^b
	June 27	24	14.720 0 ± 1.486 0^c	1.598 0 ± 0.207 1^c	16.320 0 ± 1.680 0^c

物种 Species	生长期 Growth period	样本量 No. of samples	地上生物量 Aboveground biomass (g)	地下生物量 Belowground biomass (g)	总生物量 Total biomass (g)
琉苞菊 Hyalea pulchella	April 18	33	0.026 4 ± 0.003 7^a	0.007 7 ± 0.000 7^a	0.034 1 ± 0.004 3^a
	April 28	35	0.094 4 ± 0.006 8^ab	0.010 2 ± 0.000 7^a	0.104 6 ± 0.007 2^ab
	May 8	33	0.212 4 ± 0.016 4^ab	0.031 0 ± 0.003 3^b	0.243 4 ± 0.019 4^ab
	May 18	40	0.328 0 ± 0.023 2^b	0.055 4 ± 0.003 9^c	0.383 3 ± 0.026 8^b
	May 31	40	1.431 0 ± 0.179 8^c	0.145 9 ± 0.014 2^d	1.577 0 ± 0.192 8^c
尖喙牻牛儿苗 Erodium oxyrrhynchum	April 28	35	0.018 4 ± 0.001 4^a	0.004 9 ± 0.000 3^a	0.023 3 ± 0.001 6^a
	May 8	40	0.051 3 ± 0.004 7^a	0.010 8 ± 0.000 9^b	0.062 1 ± 0.005 4^a
	May 18	40	0.113 6 ± 0.008 6^b	0.025 1 ± 0.002 1^c	0.138 7 ± 0.010 6^b
	May 31	36	0.265 4 ± 0.011 3^c	0.024 3 ± 0.003 0^c	0.289 7 ± 0.012 3^c
角果藜 Ceratocarpus arenarius	April 28	29	0.009 1 ± 0.001 0^a	0.001 9 ± 0.000 1^a	0.010 9 ± 0.001 1^a
	May 8	40	0.017 8 ± 0.001 4^a	0.003 9 ± 0.000 3^a	0.021 7 ± 0.001 7^a
	May 18	40	0.068 3 ± 0.004 9^ab	0.009 8 ± 0.000 7^a	0.078 1 ± 0.005 4^ab
	May 31	40	0.152 7 ± 0.016 4^b	0.018 5 ± 0.001 6^b	0.171 1 ± 0.017 8^b
	June 10	40	0.407 3 ± 0.044 3^c	0.037 1 ± 0.003 2^c	0.444 4 ± 0.047 4^c
	June 27	32	1.215 0 ± 0.100 9^d	0.091 5 ± 0.006 6^d	1.307 0 ± 0.106 4^d
沙蓬 Agriophyllum squarrosum	May 8	38	0.027 7 ± 0.002 5^a	0.005 8 ± 0.000 3^a	0.033 4 ± 0.002 8^a
	May 18	40	0.125 2 ± 0.010 0^a	0.019 9 ± 0.001 5^a	0.145 1 ± 0.011 4^a
	May 31	40	0.587 3 ± 0.054 0^a	0.091 2 ± 0.008 0^ab	0.678 5 ± 0.061 4^a
	June 10	17	2.364 0 ± 0.320 3^b	0.254 6 ± 0.032 3^b	2.618 0 ± 0.351 2^b
	June 27	24	14.720 0 ± 1.486 0^c	1.598 0 ± 0.207 1^c	16.320 0 ± 1.680 0^c

物种 Species	生长期 Growth period	R²	p	相关生长指数(平均值±标准误差) Allometric scaling exponent α (mean ± SD)	等速生长检验 Test of isometry
物种 Species	生长期 Growth period	R²	p	相关生长指数(平均值±标准误差) Allometric scaling exponent α (mean ± SD)	F	p
琉苞菊 Hyalea pulchella	April 18	0.461	<0.000 1	0.542 ± 0.146^c	24.440	0.000
	April 28	0.425	<0.000 1	0.821 ± 0.220^b	2.273	0.141
	May 8	0.768	<0.000 1	1.536 ± 0.271^a	26.161	0.000
	May 18	0.794	<0.000 1	0.996 ± 0.149^b	0.003	0.960
	May 31	0.816	<0.000 1	0.942 ± 0.133^b	0.739	0.395
尖喙牻牛儿苗 Erodium oxyrrhynchum	April 28	0.444	<0.000 1	0.700 ± 0.185^b	7.872	0.008
	May 8	0.672	<0.000 1	0.958 ± 0.180^a	0.215	0.646
	May 18	0.744	<0.000 1	1.148 ± 0.191^a	2.838	0.100
	May 31	0.869	<0.000 1	1.047 ± 0.132^a	0.558	0.460
角果藜 Ceratocarpus arenarius	April 28	0.707	<0.000 1	0.721 ± 0.154^b	10.221	0.004
	May 8	0.692	<0.000 1	1.058 ± 0.193^a	0.388	0.537
	May 18	0.618	<0.000 1	0.852 ± 0.173^ab	2.582	0.116
	May 31	0.846	<0.000 1	0.840 ± 0.108^b	7.520	0.009
	June 10	0.844	<0.000 1	0.703 ± 0.091^b	31.576	0.000
	June 27	0.736	<0.000 1	0.854 ± 0.163^ab	2.868	0.101
沙蓬 Agriophyllum squarrosum	May 8	0.813	<0.000 1	0.699 ± 0.102^b	25.809	0.000
	May 18	0.739	<0.000 1	0.854 ± 0.143^b	3.682	0.063
	May 31	0.839	<0.000 1	0.954 ± 0.126^ab	0.529	0.472
	June 10	0.907	<0.000 1	0.937 ± 0.157^ab	0.695	0.418
	June 27	0.802	<0.000 1	1.166 ± 0.229^a	2.632	0.119

物种 Species	生长期 Growth period	R²	p	相关生长指数(平均值±标准误差) Allometric scaling exponent α (mean ± SD)	等速生长检验 Test of isometry
物种 Species	生长期 Growth period	R²	p	相关生长指数(平均值±标准误差) Allometric scaling exponent α (mean ± SD)	F	p
琉苞菊 Hyalea pulchella	April 18	0.461	<0.000 1	0.542 ± 0.146^c	24.440	0.000
	April 28	0.425	<0.000 1	0.821 ± 0.220^b	2.273	0.141
	May 8	0.768	<0.000 1	1.536 ± 0.271^a	26.161	0.000
	May 18	0.794	<0.000 1	0.996 ± 0.149^b	0.003	0.960
	May 31	0.816	<0.000 1	0.942 ± 0.133^b	0.739	0.395
尖喙牻牛儿苗 Erodium oxyrrhynchum	April 28	0.444	<0.000 1	0.700 ± 0.185^b	7.872	0.008
	May 8	0.672	<0.000 1	0.958 ± 0.180^a	0.215	0.646
	May 18	0.744	<0.000 1	1.148 ± 0.191^a	2.838	0.100
	May 31	0.869	<0.000 1	1.047 ± 0.132^a	0.558	0.460
角果藜 Ceratocarpus arenarius	April 28	0.707	<0.000 1	0.721 ± 0.154^b	10.221	0.004
	May 8	0.692	<0.000 1	1.058 ± 0.193^a	0.388	0.537
	May 18	0.618	<0.000 1	0.852 ± 0.173^ab	2.582	0.116
	May 31	0.846	<0.000 1	0.840 ± 0.108^b	7.520	0.009
	June 10	0.844	<0.000 1	0.703 ± 0.091^b	31.576	0.000
	June 27	0.736	<0.000 1	0.854 ± 0.163^ab	2.868	0.101
沙蓬 Agriophyllum squarrosum	May 8	0.813	<0.000 1	0.699 ± 0.102^b	25.809	0.000
	May 18	0.739	<0.000 1	0.854 ± 0.143^b	3.682	0.063
	May 31	0.839	<0.000 1	0.954 ± 0.126^ab	0.529	0.472
	June 10	0.907	<0.000 1	0.937 ± 0.157^ab	0.695	0.418
	June 27	0.802	<0.000 1	1.166 ± 0.229^a	2.632	0.119

物种 Species	N (%)	P (%)	N:P (%)
琉苞菊 Hyalea pulchella	34.74	29.43	13.39
尖喙牻牛儿苗 Erodium oxyrrhynchum	33.49	23.32	14.45
角果藜 Ceratocarpus arenarius	22.97	16.36	18.26
沙蓬 Agriophyllum squarrosum	28.31	31.91	28.72