模拟氮沉降对北京东灵山辽东栎群落林下植物物种多样性的影响

doi:10.17520/biods.2018346

摘要/Abstract

摘要：

氮沉降是驱动生物多样性变化的重要因素之一。一般认为氮沉降会改变物种多样性, 而且在外源氮添加条件下, 禾草类植物和落叶灌木比杂类草和常绿灌木更具竞争优势。不过该结论更多是从高寒草甸和荒漠草原等生态系统中得到, 主要是针对同一生活型内植物之间的竞争关系, 不涉及不同生活型植物之间的相互作用, 并且由于草原和草甸等生态系统没有明显的垂直结构, 同一层次中植物的高度差异较小, 有可能高估了光照因素对植物的作用。因此从森林生态系统入手, 可以进一步阐述不同生活型植物对氮沉降的响应。本文以我国北方典型的落叶阔叶林——辽东栎(Quercus wutaishanica)林为研究对象, 设置CK (0 kg N·ha ^-1·yr ^-1)、N50 (50 kg N·ha ^-1·yr ^-1)和N100 (100 kg N·ha ^-1·yr ^-1) 3个梯度氮添加实验, 模拟氮沉降对温带森林生物多样性的影响。8年连续的氮添加实验结果显示: (1)氮添加显著降低了林下植物的物种丰富度和多样性, 改变了群落的物种组成; (2)氮添加提高了灌木植物的物种丰富度和多样性; 降低了草本植物的丰富度; (3)氮添加降低了禾草类植物的重要值, 提高了杂类草的重要值。该研究表明, 长期氮添加会显著改变林下植物的物种组成, 不同生活型植物对氮添加的响应亦有所差别。造成该现象的原因可能是由土壤环境变化(如养分含量提高, pH值下降)和植物获取光照能力强弱(如灌木植物获取光资源要多于草本植物)导致。

关键词: 氮沉降, 物种丰富度, 辽东栎, 林下植物, 物种多样性

Abstract

Nitrogen deposition is one of the major driving factors for biodiversity. Generally speaking, graminoids and deciduous shrubs compete more for nitrogen than forbs and evergreen shrubs. However, previous studies have mainly focused on a single life-form of plants in alpine meadows or desert steppes, ignoring the range of different life-forms across different habitats. Furthermore, there is no obvious canopy or vertical structure in these ecosystems that might exacerbate light limitation. Hence, there need to be more nitrogen experiments in other more complicated ecosystems (e.g. forest ecosystem) to better understand how nitrogen affects understory plants. We conducted an 8-year N fertilization experiment with three treatment levels (0 kg N·ha ^-1·yr ^-1, 50 kg N·ha ^-1·yr ^-1, 100 kg N·ha ^-1·yr ^-1) in the Quercus wutaishanica forest at Mt. Dongling, Beijing to study the response of temperate forest understory plants to nitrogen deposition. We found that: (1) Nitrogen addition reduced the species richness and biodiversity of understory plants and changed the species composition and community structure significantly. (2) Nitrogen addition increased richness of the shrub layer, but decreased richness of the herbaceous layer. (3) Graminoids responded negatively to nitrogen deposition, while forbs were positively affected. The study shows that richness and species composition change differently in response to nitrogen deposition for different life-forms of plants. In fact, the entire community of understory plants may shift in response to a change in soil resources (e.g. increase in nutrient contents and decrease in pH) and light availability (e.g. shrubs can access light easier than herbs).

Key words: nitrogen deposition, species richness, Quercus wutaishanica, understory plants, biodiversity

邹安龙, 马素辉, 倪晓凤, 蔡琼, 李修平, 吉成均 (2019) 模拟氮沉降对北京东灵山辽东栎群落林下植物物种多样性的影响. 生物多样性, 27, 607-618. DOI: 10.17520/biods.2018346.

Zou Anlong, Ma Suhui, Ni Xiaofeng, Cai Qiong, Li Xiuping, Ji Chengjun (2019) Response of understory plant diversity to nitrogen deposition in Quercus wutaishanica forests of Mt. Dongling, Beijing. Biodiversity Science, 27, 607-618. DOI: 10.17520/biods.2018346.

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链接本文: https://www.biodiversity-science.net/CN/10.17520/biods.2018346

https://www.biodiversity-science.net/CN/Y2019/V27/I6/607

图/表 9

表1 2018年各处理的林下植物基本情况, 其中‘+’代表有该物种, ‘-’代表无该物种。CK、N50、N100分别表示0、50、100 kg N·ha-1·yr-1氮添加处理。

Table 1 Conditions of understory plants during experiment in 2018, and ‘+’ means plots have this species, ‘-’ means plots do not have this species. CK, N50, N100 denote nitrogen addition 0, 50, 100 kg N·ha-1·yr-1, respectively.

物种 Species	平均高度 Average height (cm)	平均盖度 Average cover (%)	CK	N50	N100	物种 Species	平均高度 Average height (cm)	平均盖度 Average cover (%)	CK	N50	N100
草本 Herbs						莠竹 Microstegium nodosum	39.85	0.30	+	+	+
细叶薹草 Carex rigescens	15.56	14.91	+	+	+	香茶菜 Rabdosia amethystoides	68.27	0.20	+	-	+
野青茅 Deyeuxia arundinacea	30.32	33.21	+	+	+	费菜 Sedum aizoon	28.12	0.10	+	-	+
银背风毛菊 Saussurea nivea	15.47	19.68	+	+	+	展枝沙参 Adenophora divaricata	43.55	0.06	+	+	-
瓣蕊唐松草 Thalictrum petaloideum	23.25	9.43	+	+	+	裂叶蒿 Artemisia tanacetifolia	58.28	0.15	+	-	-
糙苏 Phlomis umbrosa	45.27	1.96	+	+	-	乳浆大戟 Euphorbia esula	33.36	0.24	+	-	-
穿山龙 Dioscorea nipponica	23.43	2.28	+	+	+	斑叶堇菜 Viola variegata	18.34	0.32	-	+	-
小红菊 Dendranthema chanetii	13.79	2.71	+	+	+	黄花败酱 Patrinia scabiosaefolia	30.78	0.28	-	+	-
白及 Bletilla striata	26.67	1.43	+	+	-	裂叶堇菜 Viola dissecta	15.38	0.58	-	+	-
三脉紫菀 Aster ageratoides	33.36	1.65	+	+	+	黄瓜菜 Paraixeris denticulata	18.68	0.30	-	-	+
棉团铁线莲 Clematis hexapetala	29.38	1.25	+	+	+	灌木 Shrubs
藜芦 Veratrum nigrum	31.63	1.67	+	-	-	土庄绣线菊 Spiraea pubescens	143.78	10.96	+	+	+
苍术 Atractylodes lancea	34.02	1.18	+	+	-	大花溲疏 Deutzia grandiflora	108.33	13.68	+	+	+
地榆 Sanguisorba officinalis	27.58	1.37	+	-	+	胡枝子 Lespedeza bicolor	98.82	17.45	+	+	+
龙须菜 Asparagus schoberioides	35.55	0.52	+	+	+	照山白 Rhododendron micranthum	102.96	22.78	+	+	+
轮叶沙参 Adenophora tetraphylla	44.08	0.35	+	-	-	六道木 Abelia biflora	272.94	15.33	+	+	+
蒙古风毛菊 Saussurea mongolica	36.25	1.24	+	+	+	三裂绣线菊 Spiraea trilobata	77.39	5.61	+	+	+
茜草 Rubia cordifolia	23.14	0.62	+	+	+	小花溲疏 Deutzia parviflora	129.48	5.29	+	+	+
四叶葎 Galium bungei	18.85	0.33	+	+	+	迎红杜鹃 Rhododendron mucronulatum	124.76	3.24	+	+	+
玉竹 Polygonatum odoratum	16.92	0.75	+	+	+	金银忍冬 Lonicera maackii	176.50	4.36	-	+	+
小柴胡 Bupleurum tenue	14.58	0.30	+	+	+	圆叶鼠李 Rhamnus globosa	85.43	0.50	-	-	+
蒙古蒿 Artenmisia mongolica	78.64	0.28	+	-	-	牛叠肚 Rubus crataegifolius	68.95	0.80	-	-	+
鸡腿堇菜 Viola acuminata	13.23	0.35	+	+	+

表1 2018年各处理的林下植物基本情况, 其中‘+’代表有该物种, ‘-’代表无该物种。CK、N50、N100分别表示0、50、100 kg N·ha-1·yr-1氮添加处理。

物种 Species	平均高度 Average height (cm)	平均盖度 Average cover (%)	CK	N50	N100	物种 Species	平均高度 Average height (cm)	平均盖度 Average cover (%)	CK	N50	N100
草本 Herbs						莠竹 Microstegium nodosum	39.85	0.30	+	+	+
细叶薹草 Carex rigescens	15.56	14.91	+	+	+	香茶菜 Rabdosia amethystoides	68.27	0.20	+	-	+
野青茅 Deyeuxia arundinacea	30.32	33.21	+	+	+	费菜 Sedum aizoon	28.12	0.10	+	-	+
银背风毛菊 Saussurea nivea	15.47	19.68	+	+	+	展枝沙参 Adenophora divaricata	43.55	0.06	+	+	-
瓣蕊唐松草 Thalictrum petaloideum	23.25	9.43	+	+	+	裂叶蒿 Artemisia tanacetifolia	58.28	0.15	+	-	-
糙苏 Phlomis umbrosa	45.27	1.96	+	+	-	乳浆大戟 Euphorbia esula	33.36	0.24	+	-	-
穿山龙 Dioscorea nipponica	23.43	2.28	+	+	+	斑叶堇菜 Viola variegata	18.34	0.32	-	+	-
小红菊 Dendranthema chanetii	13.79	2.71	+	+	+	黄花败酱 Patrinia scabiosaefolia	30.78	0.28	-	+	-
白及 Bletilla striata	26.67	1.43	+	+	-	裂叶堇菜 Viola dissecta	15.38	0.58	-	+	-
三脉紫菀 Aster ageratoides	33.36	1.65	+	+	+	黄瓜菜 Paraixeris denticulata	18.68	0.30	-	-	+
棉团铁线莲 Clematis hexapetala	29.38	1.25	+	+	+	灌木 Shrubs
藜芦 Veratrum nigrum	31.63	1.67	+	-	-	土庄绣线菊 Spiraea pubescens	143.78	10.96	+	+	+
苍术 Atractylodes lancea	34.02	1.18	+	+	-	大花溲疏 Deutzia grandiflora	108.33	13.68	+	+	+
地榆 Sanguisorba officinalis	27.58	1.37	+	-	+	胡枝子 Lespedeza bicolor	98.82	17.45	+	+	+
龙须菜 Asparagus schoberioides	35.55	0.52	+	+	+	照山白 Rhododendron micranthum	102.96	22.78	+	+	+
轮叶沙参 Adenophora tetraphylla	44.08	0.35	+	-	-	六道木 Abelia biflora	272.94	15.33	+	+	+
蒙古风毛菊 Saussurea mongolica	36.25	1.24	+	+	+	三裂绣线菊 Spiraea trilobata	77.39	5.61	+	+	+
茜草 Rubia cordifolia	23.14	0.62	+	+	+	小花溲疏 Deutzia parviflora	129.48	5.29	+	+	+
四叶葎 Galium bungei	18.85	0.33	+	+	+	迎红杜鹃 Rhododendron mucronulatum	124.76	3.24	+	+	+
玉竹 Polygonatum odoratum	16.92	0.75	+	+	+	金银忍冬 Lonicera maackii	176.50	4.36	-	+	+
小柴胡 Bupleurum tenue	14.58	0.30	+	+	+	圆叶鼠李 Rhamnus globosa	85.43	0.50	-	-	+
蒙古蒿 Artenmisia mongolica	78.64	0.28	+	-	-	牛叠肚 Rubus crataegifolius	68.95	0.80	-	-	+
鸡腿堇菜 Viola acuminata	13.23	0.35	+	+	+

表2 氮添加对2011年和2018年不同处理优势物种重要值变化的影响(平均值 ± 标准误差, n = 3)。不同字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Table 2 Influence of nitrogen addition on dominant species importance value of different treatments in 2011 and 2018 (mean ± SE, n = 3). Different lowercase letters indicate significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

物种 Species	2011			2018
物种 Species	CK	N50	N100	CK	N50	N100
草本 Herbaceous
细叶薹草 Carex rigescens	15.53 ± 3.93^a	14.25 ± 1.95^a	20.53 ± 1.11^a	10.16 ± 0.98^a	8.29 ± 0.36^a	4.17 ± 0.21^b
野青茅 Deyeuxia arundinacea	40.82 ± 5.15^a	36.64 ± 4.11^a	32.14 ± 3.66^a	39.95 ± 7.41^a	35.94 ± 3.91a	34.24 ± 4.66^a
银背风毛菊 Saussurea nivea	8.26 ± 3.99^a	9.73 ± 1.28^a	8.49 ± 2.29^a	9.77 ± 2.45^a	12.49 ± 4.78^a	8.78 ± 1.75^a
瓣蕊唐松草 Thalictrum petaloideum	3.73 ± 1.31^a	4.17 ± 2.45^a	7.18 ± 1.74^a	4.73 ± 1.53^a	9.84 ± 4.12^a	8.97 ± 3.93^a
灌木 Shrubs
土庄绣线菊 Spiraea pubescens	22.32 ± 3.53^a	18.17 ± 5.41^a	18.74 ± 6.22^a	21.19 ± 3.03^a	20.81 ± 2.48^a	9.30 ± 3.63^b
大花溲疏 Deutzia grandiflora	12.57 ± 2.57^a	11.64 ± 2.39^a	12.53 ± 3.26^a	7.00 ± 2.12^a	15.80 ± 4.64^b	26.12 ± 2.52^b
胡枝子 Lespedeza bicolor	15.18 ± 2.10^a	13.09 ± 3.72^a	16.08 ± 4.64^a	15.15 ± 6.16^a	20.10 ± 1.91^a	22.33 ± 6.26^a
照山白 Rhododendron micranthum	11.56 ± 5.66^a	13.99 ± 2.81^a	16.50 ± 1.78^a	15.83 ± 4.44^a	22.50 ± 3.73^a	21.59 ± 2.82^a
六道木 Abelia biflora	9.31 ± 1.54^a	9.93 ± 5.22^a	6.84 ± 1.06^a	8.80 ± 5.55^a	13.50 ± 8.48^a	12.50 ± 3.73^a

图1 氮添加对2011年和2018年林下植物物种丰富度和Shannon-Wiener指数的影响(平均值 ± 标准误差, n = 3)。不同小写字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Fig. 1 Species richness and Shannon-Wiener index of understory plant varied with nitrogen addition in 2011 and 2018 (mean ± SE, n = 3). Different lowercase letters indicate significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

图2 氮添加对2011年和2018年草本层植物物种丰富度、Shannon-Wiener指数、植物高度、植物盖度的影响(平均值 ± 标准误差, n = 3)。不同小写字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Fig. 2 Species richness, Shannon-Wiener index, plant height and plant cover of herbaceous varied with nitrogen addition in 2011 and 2018 (mean ± SE, n = 3). Different lowercase letter indicates significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

图3 氮添加对2011年和2018年灌木层植物物种丰富度、Shannon-Wiener指数、植物高度、植物盖度的影响(平均值 ± 标准误差, n = 3)。不同小写字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Fig. 3 Species richness, Shannon-Wiener index, plant height and plant cover of shrubs varied with nitrogen addition in 2011 and 2018 (mean ± SE, n = 3). Different lowercase letters indicate significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

图4 氮添加对2011年和2018年林下植物基尼系数的影响(平均值 ± 标准误差, n = 3)。不同小写字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Fig. 4 The Gini coefficient of understory plants varied with nitrogen addition (mean ± SE, n = 3). Different lowercase letters indicate significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

图5 氮添加对2018年林下优势种植物叶片全碳和全含量的影响(平均值 ± 标准误差, n = 3)。不同小写字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Fig. 5 Leaf total carbon and total nitrogen of understory dominant species varied with nitrogen addition in 2018 (mean ± SE, n = 3). Different lowercase letters indicate significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

图6 氮添加对2018年土壤全碳、全氮、全磷以及pH值的影响(平均值 ± 标准误差, n = 3)。不同小写字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Fig. 6 Soil total carbon, total nitrogen, total phosphorus and pH value varied with nitrogen addition in 2018 (mean ± SE, n = 3). Different lowercase letters indicate significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

图7 氮添加对2011年和2018年禾草类植物以及杂类草重要值变化的影响(平均值 ± 标准误差, n = 3)。不同小写字母表示各处理差异显著(P < 0.05)。CK、N50、N100含义同表1。

Fig. 7 The importance value of graminoids and forbs varied with nitrogen addition in 2011 and 2018 (mean ± SE, n = 3). Different lowercase letters indicate significant difference among treatments (P < 0.05). CK, N50, N100 see Table 1.

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