Foliar nitrogen and phosphorus stoichiometry of alien invasive plants and co-occurring natives in Xishuangbanna

doi:10.17521/cjpe.2016.0052

Abstract

Abstract:

Aims How alien invasive plants and co-occurring native plants utilize nutrients is one of major issues in invasion ecology. Foliar nitrogen (N) and phosphorus (P) contents and stoichiometry can elucidate the uptake ability and limitation status of nutrients in plants, which provides basic knowledge for understanding the invading ability and co-occurrence or disappearance of plants.
Methods Based on typical alien invasive plants (Chromolaena odorata, Ageratina adenophora) and native plants in southwestern China, this study focused on strategies of N and P utilization among invasive plants and native plants under different invasion conditions. The species compositions, aboveground biomass, leaf N and P contents and leaf N:P were investigated for plants in plots with no invasion and with different invasion extents (estimated by the plot-based percentage of invaders’ biomass in total community) at Mt. Kongming in Xishuangbanna region, Yunnan Province, China.
Important findings The species number decreased significantly with the invasion extent of both C. odorata and A. adenophora, although the aboveground biomass was greatly enhanced. Leaf N and P contents did not differ between the two studied invaders, but they showed significantly higher N and P levels than both co-occurring and only native species (p < 0.05). Besides, leaf N and P contents of invaders increased with the invasion extent, and leaf N of native plants also showed an increasing trend with the invasion extent. When the influence of invasion was checked for the same species, leaf P contents decreased, whereas leaf N and N:P increased for most native plants under invasion. Based on the absolute foliar N and P contents, N:P values, we inferred that native plants were still limited by N, although N availability might be enhanced by invasion. Both invasive plants had leaf N:P values lower than 10, suggesting a higher P uptake relative to N uptake. All above results highlighted a higher N and P uptake of typical alien invasive plants in southwestern China.

Key words: plant invasion, nitrogen:phosphorus, ecological stoichiometry, Chromolaena odorata, Ageratina adenophora

Chao-Chen HU, Xue-Yan LIU, Yan-Bao LEI, Yun-Hong TAN, Peng ZHANG, Yu-Ping DONG, Cong-Qiang LIU. Foliar nitrogen and phosphorus stoichiometry of alien invasive plants and co-occurring natives in Xishuangbanna[J]. Chin J Plan Ecolo, 2016, 40(11): 1145-1153.

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Figures/Tables 5

References 42

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科 Family	无入侵样方本地植物(出现的样方数) Species in plots with no invasion (n)	飞机草入侵样方本地植物(出现的样方数) Native species in plots invaded by C. odorata (n)	紫茎泽兰入侵样方本地植物 (出现的样方数) Native species in plots invaded by A. adenophora (n)
禾本科 Poaceae	鼠尾粟 Sporobolus fertilis (3)	鼠尾粟 Sporobolus fertilis (4)	鼠尾粟 Sporobolus fertilis (2)
	两耳草 Paspalum conjugatum (3)	两耳草 Paspalum conjugatum (4)	两耳草 Paspalum conjugatum (4)
	白茅 Imperata cylindrica (3)	白茅 Imperata cylindrica (4)	白茅 Imperata cylindrica (4)
	圆果雀稗 Paspalum orbiculare (3)	圆果雀稗 Paspalum orbiculare (1)	圆果雀稗 Paspalum orbiculare (1)
	硬秆子草 Capillipedium assimile (3)	硬秆子草 Capillipedium assimile (2)	硬秆子草 Capillipedium assimile (3)
	五节芒 Miscanthus floridulus (3)	五节芒 Miscanthus floridulus (1)	五节芒 Miscanthus floridulus (2)
	金丝草 Pogonatherum crinitum (2)	金丝草 Pogonatherum crinitum (1)	拔毒散 Sida szechuensis (1)
	狗尾草 Setaria viridis (2)	狗尾草 Setaria viridis (1)
		柳叶箬 Isachne globosa (1)
大戟科 Euphorbiaceae	黑面神 Breynia fruticosa (3)	黑面神 Breynia fruticosa (1)	黑面神 Breynia fruticosa (1)
	艾橡树 Glochidion oblatum (2)		艾橡树 Glochidion oblatum (1)
	叶下珠 Phyllanthus urinaria (1)
豆科 Leguminosae	假地豆 Desmodium heterocarpon (2)	假地豆 Desmodium heterocarpon (3)	假地豆 Desmodium heterocarpon (2)
	三点金 Desmodium triflorum (2)	三点金 Desmodium triflorum (1)	假木豆 Dendrolobium triangulare (1)
	云南千斤拔 Flemingia wallichii (1)		猪屎豆 Crotalaria pallida (1)
茜草科 Rubiaceae	水锦树 Wendlandia uvariifolia (2)	水锦树 Wendlandia uvariifolia (1)	水锦树 Wendlandia uvariifolia (1)
	松叶耳草 Hedyotis pinifolia (3)	松叶耳草 Hedyotis pinifolia (2)	松叶耳草 Hedyotis pinifolia (2)
	耳草 Hedyotis auricularia (1)
蔷薇科 Rosaceae	龙芽草 Agrimonia pilosa (3)	龙芽草 Agrimonia pilosa (2)	龙芽草 Agrimonia pilosa (2)
蔷薇科 Rosaceae	次蕨麻 Potentilla anserina (1)
莎草科 Cyperaceae	香附子 Cyperus rotundus (1)	水蜈蚣 Kyllinga brevifolia (1)	香附子 Cyperus rotundus (1)
	十字薹草 Carex cruciata (2)		十字薹草 Carex cruciata (2)
			水蜈蚣 Kyllinga brevifolia (1)
锦葵科 Malvaceae	地桃花 Urena lobata (3)	地桃花 Urena lobata (5)	地桃花 Urena lobata (2)
爵床科 Acanthaceae	爵床 Rostellularia procumbens (3)	爵床 Rostellularia procumbens (2)	爵床 Rostellularia procumbens (2)
野牡丹科 Melastomataceae	多花野牡丹 Melastoma affine (3)	多花野牡丹 Melastoma affine (2)	多花野牡丹 Melastoma affine (2)
菊科 Asteraceae	地胆草 Elephantopus scaber (3)	地胆草 Elephantopus scaber (3)	地胆草 Elephantopus scaber (1)
毛茛科 Ranunculaceae	铁扫帚 Clematis hexapetala (2)	铁扫帚 Clematis hexapetala (2)
荨麻科 Urticaceae	糯米团 Memorialis hirta (1)
唇形科 Labiatae	大籽筋骨草 Ajuga macrosperma (1)
椴树科 Tiliaceae	刺蒴麻 Triumfetta rhomboidea (1)
百合科 Liliaceae	野百合 Crotalaria sessiliflora (1)

科 Family	无入侵样方本地植物(出现的样方数) Species in plots with no invasion (n)	飞机草入侵样方本地植物(出现的样方数) Native species in plots invaded by C. odorata (n)	紫茎泽兰入侵样方本地植物 (出现的样方数) Native species in plots invaded by A. adenophora (n)
禾本科 Poaceae	鼠尾粟 Sporobolus fertilis (3)	鼠尾粟 Sporobolus fertilis (4)	鼠尾粟 Sporobolus fertilis (2)
	两耳草 Paspalum conjugatum (3)	两耳草 Paspalum conjugatum (4)	两耳草 Paspalum conjugatum (4)
	白茅 Imperata cylindrica (3)	白茅 Imperata cylindrica (4)	白茅 Imperata cylindrica (4)
	圆果雀稗 Paspalum orbiculare (3)	圆果雀稗 Paspalum orbiculare (1)	圆果雀稗 Paspalum orbiculare (1)
	硬秆子草 Capillipedium assimile (3)	硬秆子草 Capillipedium assimile (2)	硬秆子草 Capillipedium assimile (3)
	五节芒 Miscanthus floridulus (3)	五节芒 Miscanthus floridulus (1)	五节芒 Miscanthus floridulus (2)
	金丝草 Pogonatherum crinitum (2)	金丝草 Pogonatherum crinitum (1)	拔毒散 Sida szechuensis (1)
	狗尾草 Setaria viridis (2)	狗尾草 Setaria viridis (1)
		柳叶箬 Isachne globosa (1)
大戟科 Euphorbiaceae	黑面神 Breynia fruticosa (3)	黑面神 Breynia fruticosa (1)	黑面神 Breynia fruticosa (1)
	艾橡树 Glochidion oblatum (2)		艾橡树 Glochidion oblatum (1)
	叶下珠 Phyllanthus urinaria (1)
豆科 Leguminosae	假地豆 Desmodium heterocarpon (2)	假地豆 Desmodium heterocarpon (3)	假地豆 Desmodium heterocarpon (2)
	三点金 Desmodium triflorum (2)	三点金 Desmodium triflorum (1)	假木豆 Dendrolobium triangulare (1)
	云南千斤拔 Flemingia wallichii (1)		猪屎豆 Crotalaria pallida (1)
茜草科 Rubiaceae	水锦树 Wendlandia uvariifolia (2)	水锦树 Wendlandia uvariifolia (1)	水锦树 Wendlandia uvariifolia (1)
	松叶耳草 Hedyotis pinifolia (3)	松叶耳草 Hedyotis pinifolia (2)	松叶耳草 Hedyotis pinifolia (2)
	耳草 Hedyotis auricularia (1)
蔷薇科 Rosaceae	龙芽草 Agrimonia pilosa (3)	龙芽草 Agrimonia pilosa (2)	龙芽草 Agrimonia pilosa (2)
蔷薇科 Rosaceae	次蕨麻 Potentilla anserina (1)
莎草科 Cyperaceae	香附子 Cyperus rotundus (1)	水蜈蚣 Kyllinga brevifolia (1)	香附子 Cyperus rotundus (1)
	十字薹草 Carex cruciata (2)		十字薹草 Carex cruciata (2)
			水蜈蚣 Kyllinga brevifolia (1)
锦葵科 Malvaceae	地桃花 Urena lobata (3)	地桃花 Urena lobata (5)	地桃花 Urena lobata (2)
爵床科 Acanthaceae	爵床 Rostellularia procumbens (3)	爵床 Rostellularia procumbens (2)	爵床 Rostellularia procumbens (2)
野牡丹科 Melastomataceae	多花野牡丹 Melastoma affine (3)	多花野牡丹 Melastoma affine (2)	多花野牡丹 Melastoma affine (2)
菊科 Asteraceae	地胆草 Elephantopus scaber (3)	地胆草 Elephantopus scaber (3)	地胆草 Elephantopus scaber (1)
毛茛科 Ranunculaceae	铁扫帚 Clematis hexapetala (2)	铁扫帚 Clematis hexapetala (2)
荨麻科 Urticaceae	糯米团 Memorialis hirta (1)
唇形科 Labiatae	大籽筋骨草 Ajuga macrosperma (1)
椴树科 Tiliaceae	刺蒴麻 Triumfetta rhomboidea (1)
百合科 Liliaceae	野百合 Crotalaria sessiliflora (1)

	无入侵样方 No invasion plot	飞机草入侵样方 Chromolaena odorata invasion plot		紫茎泽兰入侵样方 Ageratina adenophora invasion plot
	本地植物 Native plant (n = 52)	飞机草 C. odorata (n = 6)	本地植物 Native plant (n = 40)	紫茎泽兰 A. adenophora (n = 6)	本地植物 Native plant (n = 36)
氮含量 N concentration (%)	1.1 ± 0.4^a	2.4 ± 0.3^b	1.2 ± 0.5^a	2.3 ± 0.3^b	1.2 ± 0.6^a
磷含量 P concentration (%)	0.18 ± 0.10^a	0.33 ± 0.11^b	0.12 ± 0.09^a	0.24 ± 0.08^b	0.14 ± 0.11^a
氮磷比值 N:P value	7.0 ± 3.5^a	8.3 ± 2.3^a	10.4 ± 4.9^a	10.4 ± 2.7^a	9.5 ± 4.8^a

	无入侵样方 No invasion plot	飞机草入侵样方 Chromolaena odorata invasion plot		紫茎泽兰入侵样方 Ageratina adenophora invasion plot
	本地植物 Native plant (n = 52)	飞机草 C. odorata (n = 6)	本地植物 Native plant (n = 40)	紫茎泽兰 A. adenophora (n = 6)	本地植物 Native plant (n = 36)
氮含量 N concentration (%)	1.1 ± 0.4^a	2.4 ± 0.3^b	1.2 ± 0.5^a	2.3 ± 0.3^b	1.2 ± 0.6^a
磷含量 P concentration (%)	0.18 ± 0.10^a	0.33 ± 0.11^b	0.12 ± 0.09^a	0.24 ± 0.08^b	0.14 ± 0.11^a
氮磷比值 N:P value	7.0 ± 3.5^a	8.3 ± 2.3^a	10.4 ± 4.9^a	10.4 ± 2.7^a	9.5 ± 4.8^a