Leaf traits of Artemisia ordosica at different dune fixation stages in Mau Us Sandy Land

doi:10.17521/cjpe.2022.0257

Abstract

Abstract:

Aims The dynamic changes of plant leaf traits during sand dune fixation in semi-arid areas is of significance to reveal the ecologically adaptative strategies of sand plants to environmental changes in the region.
Methods Eleven leaf traits of a typical species, Artemisia ordosica, in the Mau Us Sandy Land, was measured at its four different stages of sand dune fixation (semi-fixed dune, fixed dune, fixed dune with biological soil crusts, fixed dune with abundant herbaceous plants). The variations in the leaf traits and their relationships over different sand-fixation stages were tested using correlation, principal component and similarity analysis.
Important findings (1) The leaf area (LA) and maximum net photosynthetic rate (A_max) in the semi-fixed dune stage were significantly higher than the other three stages of sand dune fixation, leaf carbon content increased significantly and then decreased slightly as the dunes gradually fixed. Leaf phosphorus content at the semi-fixed dune and the fixed dune with biological soil crusts was significantly higher than that at other two stages, and being highest at the semi-fixed dune stage. These variations in leaf traits indicated that A. ordosica tended to enhance photosynthesis for survival in the semi-fixed dune stage. (2) Photosynthesis-related traits of LA and specific leaf area (SLA) were significantly and negatively correlated with physically defense-related structure traits of leaf dry matter content (LDMC) and leaf tissue density, respectively, regardless of the stage of sand dune fixation. The results demonstrated that in order to adapt to the dry environment, the investment in leaf photosynthetic capacity would decrease with the increase of investment in physical defense structure. It also showed that there was a trade-off between the plant growth and defense capability enhancement at different stages of sand dune fixation. (3) The leaf chemical traits were significantly correlated with the leaf morphological and physiological traits. And the leaf traits tended to develop from “rapid investment - return” to “slow investment - return” as sand dune fixed. The results demonstrated that sandy plants could adjust their resource use trade-off strategy to adapt to different environmental changes through leaf traits and interrelationship optimization.

Key words: leaf trait, resource trade-off strategy, sand fixation stage, Artemisia ordosica

DAI Yuan-Meng, LI Man-Le, XU Ming-Ze, TIAN Yun, ZHAO Hong-Xian, GAO Sheng-Jie, HAO Shao-Rong, LIU Peng, JIA Xin, ZHA Tian-Shan. Leaf traits of Artemisia ordosica at different dune fixation stages in Mau Us Sandy Land[J]. Chin J Plant Ecol, 2022, 46(11): 1376-1387.

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URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2022.0257

https://www.plant-ecology.com/EN/Y2022/V46/I11/1376

Figures/Tables 8

Fig. 1 Characteristics of different dune fixation stages in Mau Us Sandy Land. A, Semi-fixed dune stage. B, Fixed dune stage. C, Fixed dune covered with biological soil crusts. D, Fixed dune with abundant herbaceous plants.

Table 1 Vegetation characteristics and soil physical-chemical properties at different dune fixation stages in Mau Us Sandy Land (mean ± SE)

植被特征与土壤指标 Vegetation characteristic and soil indicator	半固定沙丘 Semi-fixed dune stage	固定沙丘 Fixed dune stage	土壤结皮固定沙丘 Fixed dune covered with biological soil crusts	草本植物固定沙丘 Fixed dune with abundant herbaceous plant
植被覆盖度 Vegetation coverage (%)	23.29 ± 2.39^a	30.27 ± 2.32^a	46.43 ± 3.19^b	61.80 ± 2.80^c
黑沙蒿覆盖度 Coverage of Artemisia ordosica (%)	11.54 ± 1.24^a	22.11 ± 1.72^b	35.24 ± 1.37^c	38.23 ± 2.84^c
土壤有机碳含量 Soil organic carbon content (g·kg^-1)	0.55 ± 0.02^a	2.40 ± 0.23^b	0.94 ± 0.02^a	1.43 ± 0.05^a
土壤全氮含量 Soil total nitrogen content (g·kg^-1)	0.22 ± 0.01^a	0.31 ± 0.04^b	0.24 ± 0.01^ab	0.30 ± 0.01^ab
土壤全磷含量 Soil total phosphorus content (g·kg^-1)	0.05 ± 0.00^a	0.19 ± 0.02^b	0.07 ± 0.00^a	0.12 ± 0.01^a
优势物种 Dominant species	黑沙蒿、塔落岩黄耆、虫实、草木樨状黄耆、沙蓬 Artemisia ordosica, Corethrodendron lignosum var. leave, Corispermum sp., Astragalus melilotoides, Agriophyllum squarrosum	黑沙蒿、柠条锦鸡儿、草木樨状黄耆、华北白前、达乌里胡枝子 Artemisia ordosica, Caragana korshinskii, Astragalus melilotoides, Vincetoxicum mongolicum, Lespedeza davurica	黑沙蒿、塔落岩黄耆、草木樨状黄耆、华北白前、中华草沙蚕 Artemisia ordosica, Corethrodendron lignosum var. leave, Astragalus melilotoides, Vincetoxicum mongolicum, Tripogon chinensis	黑沙蒿、塔落岩黄耆、赖草、糙隐子草、华北白前 Artemisia ordosica, Corethrodendron lignosum var. leave, Leymus secalinus, Cleistogenes squarrosa, Vincetoxicum mongolicum

Fig. 2 Effects of different dune fixation stages on leaf traits of Artemisia ordosica in Mau Us Sandy Land (mean ± SE). Amax, maximum net photosynthetic rate; C:N, leaf carbon content to nitrogen content ratio; LA, leaf area; LCC, leaf carbon content; LDMC, leaf dry matter content; LNC, leaf nitrogen content; LPC, leaf phosphorus content; LT, leaf thickness; LTD, leaf tissue density; N:P, leaf nitrogen content to phosphorus content ratio; SLA, specific leaf area. CV, coefficient of variation. D1, semi-fixed dune stage; D2, fixed dune stage; D3, fixed dune covered with biological soil crusts; D4, fixed dune with abundant herbaceous plants.

Fig. 3 Relationships between leaf traits of Artemisia ordosica at different dune fixation stages in Mau Us Sandy Land. Amax, maximum net photosynthetic rate; LA, leaf area; LDMC, leaf dry matter content; LT, leaf thickness; LTD, leaf tissue density; SLA, specific leaf area. D1, semi-fixed dune stage; D2, fixed dune stage; D3, fixed dune covered with biological soil crusts; D4, fixed dune with abundant herbaceous plants.

Table 2 Pearson correlation coefficients among leaf traits of Artemisia ordosica at the dune fixation stages in Mau Us Sandy Land

	LA	SLA	LT	LTD	LDMC	A_max	LCC	LNC	LPC	C:N	N:P
LA	1.00
SLA	0.22	1.00
LT	-0.10	-0.15	1.00
LTD	-0.22	-0.72^***	-0.54^***	1.00
LDMC	-0.66^***	-0.41^*	0.24	0.29	1.00
A_max	0.63^***	-0.16	-0.02	0.08	-0.35^*	1.00
LCC	-0.36^*	0.13	0.07	-0.17	0.16	-0.49^**	1.00
LNC	-0.11	0.13	-0.16	0.01	-0.15	-0.07	0.19	1.00
LPC	0.50^***	0.22	-0.10	-0.19	-0.41^*	0.17	0.01	0.28	1.00
C:N	-0.03	-0.05	0.17	-0.11	0.19	-0.17	0.43^**	-0.79^***	-0.17	1.00
N:P	-0.51^**	-0.15	-0.02	0.23	0.37^*	-0.11	-0.12	0.07	-0.91^***	-0.21	1.00

Fig. 4 Results of principle component (PC) analysis of Artemisia ordosica leaf traits in different dune fixation stages in Mau Us Sandy Land. A, Main leaf trait load of Artemisia ordosica. B, Response of Artemisia ordosica to different stages of dune fixation. Amax, maximum net photosynthetic rate; C:N, leaf carbon content to nitrogen content ratio; LA, leaf area; LCC, leaf carbon content; LDMC, leaf dry matter content; LNC, leaf nitrogen content; LPC, leaf phosphorus content; LT, leaf thickness; LTD, leaf tissue density; N:P, leaf nitrogen content to phosphorus content ratio; SLA, specific leaf area. D1, semi-fixed dune stage; D2, fixed dune stage; D3, fixed dune covered with biological soil crusts; D4, fixed dune with abundant herbaceous plants.

Table 3 Loadings and interpreted variance of leaf traits in principal component analysis in Mau Us Sandy Land

叶性状 Leaf trait	主成分1 Principal component 1	主成分2 Principal component 2	主成分3 Principal component 3
LA	0.47	0.07	0.27
SLA	0.26	-0.28	-0.32
LT	-0.07	-0.31	0.14
LTD	-0.23	0.46	0.14
LDMC	-0.44	-0.05	0.04
A_max	0.26	0.32	0.36
LCC	-0.13	-0.42	-0.27
LNC	0.09	0.23	-0.62
LPC	0.44	-0.06	-0.10
C:N	-0.12	-0.46	0.43
N:P	-0.40	0.23	-0.10
方差比例 Variance ratio	29.20%	20.03%	17.11%
累计方差比例 Cumulative variance ratio	29.20%	49.23%	66.34%

Fig. 5 Analysis of leaf traits similarities of Artemisia ordosica in different dune fixation stages in Mau Us Sandy Land. D1, semi-fixed dune stage; D2, fixed dune stage; D3, fixed dune covered with biological soil crusts; D4, fixed dune with abundant herbaceous plants.

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