百山祖常绿阔叶林灌草层物种组成和 分布的10年动态

doi:10.17520/biods.2016095

摘要/Abstract

摘要：

森林群落的动态受多方面因素的影响。林下的草本植物和木本植物幼苗幼树对于森林的更新及动态具有重要作用。为了解百山祖常绿阔叶林群落下层植物物种组成和分布的动态变化, 我们分析了2003-2013年间百山祖5 ha森林动态样地灌草层物种(包括DBH < 1 cm的木本植物和所有草本植物)在物种重要值、α多样性以及物种分布等方面的变化。结果表明: (1) 10年间, 群落灌草层植物个体数减少了28.7%, 其中草质藤本植物个体数下降比例最大(76.9%), 而乔木的幼苗和幼树下降比例最小(14.4%); (2)整个灌草层的物种数明显下降, 同时乔木的幼苗和幼树及直立灌木的均匀度均下降, 而草本植物均匀度有所上升; (3)除短尾柯(Lithocarpus brevicaudatus)、叶萼山矾(Symplocos phyllocalyx)、显脉野木瓜(Stauntonia conspicua)和福建悬钩子(Rubus fujianensis)等植物重要值逆势上扬外, 直立灌木物种重要值10年间的变化值与其在2003年时的重要值呈显著正相关, 而其余各类生活型植物都显示, 初始重要值越高的物种在10年后下降幅度越大; (4)物种分布与生境类型的相关性变化复杂, 除与山谷生境正相关的物种数量增加外, 研究期间与生境存在显著相关性的物种数都有所减少; (5) 10年来仅陡坡处物种多样性指数没有显著下降。总体来说, 百山祖常绿阔叶林灌草层群落仍未达到顶极状态, 2003-2013年间正缓慢向顶极群落演替。群落内部的种间和种内竞争应是当前群落动态的主导因素。

关键词: 森林动态, 物种组成, 生境相关, 灌草层, 气候变暖

Abstract

Forest dynamics are directly driven by multiple factors, including changes in understory grasses and small woody plants. Yet the dynamics of these small woody plants and grasses as well as underlying ecological forces are still not fully understood, particularly in evergreen forests. Here, we analyzed ten year (from 2003 to 2013) shifts in species importance values, diversity, habitat associations, and distributions of understory small woody plants and grasses (including herbs, herbal lianas and woody plants with diameter at breast height (DBH) < 1 cm) in a 5-ha subtropical forest plot in Baishanzu, Zhejiang, China. Results showed that the number of individuals decreased by 28.7% overall, 76.9% in herbal lianas, and 14.4% in seedlings or saplings of tree species. Species richness of shrubs and grasses decreased notably, while evenness decreased in small woody plant communities and increased in herb communities. Except for Lithocarpus brevicaudatus, Symplocos phyllocalyx, Stauntonia conspicua, Rubus fujianensis, whose importance values increased conversely, correlations between changes of importance values during the ten-years period and initial importance values were positive among erective shrub species and negative among species of other life forms. Shifts in species-habitat associations were complex, as the number of species with significant habitat-associations decreased during the ten year period, except for the increasing richness of species with positive gully associations. Only species diversity in steep slope habitats did not decrease significantly. These findings suggest the small woody plants and grasses of the Baishanzu evergreen forest have not yet reached climax status, and were developing to the climax over 2003 to 2013. Internal community-level processes, such as intraspecific and interspecific competitions, should be dominant factors that drive the forest dynamics.

Key words: forest dynamics, species composition, habitat association, shrub and grass layer, climate warming

黄云霞, 徐萱, 张莉芗, 宋玥, 骆争荣 (2016) 百山祖常绿阔叶林灌草层物种组成和分布的10年动态. 生物多样性, 24, 1353-1363. DOI: 10.17520/biods.2016095.

Yunxia Huang, Xuan Xu, Lixiang Zhang, Yue Song, Zhengrong Luo (2016) Ten-years period of grass and small woody plant dynamics in a 5-ha evergreen forest plot in Baishanzu, Zhejiang Province. Biodiversity Science, 24, 1353-1363. DOI: 10.17520/biods.2016095.

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链接本文: https://www.biodiversity-science.net/CN/10.17520/biods.2016095

https://www.biodiversity-science.net/CN/Y2016/V24/I12/1353

图/表 6

参考文献 41

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生活型 Life form	个体数 No. of individuals		物种数 No. of species		Camargo指数 Camargo index
生活型 Life form	2003	2013	2003	2013	2003	2013
乔木 Tree species	9,402	8,052	29	26	0.224	0.173
直立灌木 Erective shrubs	43,352	29,003	79	72	0.167	0.135
蔓性灌木 Spreading shrubs	3,431	2,453	10	9	0.176	0.229
木质藤本 Woody lianas	1,630	1,170	17	16	0.191	0.130
草质藤本 Herbaceous lianas	26	6	2	2	0.692	1.000
草本蕨类 Herbaceous ferns	21,333	16,323	6	6	0.198	0.225
其他草本 Other herbs	6,549	4,090	37	35	0.145	0.192
总计 Total	85,723	61,097	180	166	0.127	0.114

生活型 Life form	个体数 No. of individuals		物种数 No. of species		Camargo指数 Camargo index
生活型 Life form	2003	2013	2003	2013	2003	2013
乔木 Tree species	9,402	8,052	29	26	0.224	0.173
直立灌木 Erective shrubs	43,352	29,003	79	72	0.167	0.135
蔓性灌木 Spreading shrubs	3,431	2,453	10	9	0.176	0.229
木质藤本 Woody lianas	1,630	1,170	17	16	0.191	0.130
草质藤本 Herbaceous lianas	26	6	2	2	0.692	1.000
草本蕨类 Herbaceous ferns	21,333	16,323	6	6	0.198	0.225
其他草本 Other herbs	6,549	4,090	37	35	0.145	0.192
总计 Total	85,723	61,097	180	166	0.127	0.114

物种 Species	株数 Number of individuals		频度 Frequency		重要值排序 Rank of IV
物种 Species	2003	2013	2003	2013	2003	2013
木质藤本植物(前3位) Woody lianas (Top 3)
显脉野木瓜 Stauntonia conspicua	994 (60.98%)	914 (78.12%)	474 (59.62%)	524 (77.86%)	1	1
钻地风 Schizophragma integrifolium	264 (16.19%)	148 (12.65%)	119 (14.97%)	68 (10.10%)	2	2
南五味子 Kadsura longipedunculata	167 (10.25%)	21 (1.79%)	83 (10.44%)	16 (2.38%)	3	3
乔木(前3位) Tree species (Top 3)
短尾柯 Lithocarpus brevicaudatus	3,430 (36.48%)	4,366 (54.22%)	1,288 (26.62%)	1,536 (38.79%)	1	1
多脉青冈 Cyclobalanopsis multinervis	1,716 (18.25%)	1,200 (14.90%)	885 (18.28%)	747 (18.86%)	2	2
木荷 Schima superba	980 (10.42%)	621 (7.71%)	468 (9.67%)	362 (9.18%)	3	3
直立灌木(前5位) Erective shrubs (Top 5)
连蕊茶 Camellia cuspidata	5,894 (13.59%)	4,384 (19.38%)	1,561 (13.18%)	1,558 (16.07%)	1	1
新木姜子 Neolitsea aurata	5,856 (13.51%)	4,318 (14.89%)	1,517 (12.81%)	1,501 (15.22%)	2	2
薄叶山矾 Symplocos anomala	4,560 (10.52%)	1,691 (0.62%)	973 (5.22%)	875 (1.43%)	3	14
叶萼山矾 Symplocos phyllocalyx	795 (1.83%)	4,426 (15.26%)	142 (1.20%)	1,117 (11.33%)	15	3
四川山矾 Symplocos setchuensis	4,032 (9.30%)	2,912 (10.04%)	990 (5.36%)	1,000 (10.14%)	4	4
厚叶红淡比 Cleyera pachyphylla	4,824 (11.13%)	2,114 (7.29%)	525 (4.43%)	592 (6.00%)	5	5
蔓性/攀援灌木(前3位) Spreading shrubs (Top 3)
尖叶菝葜 Smilax arisanensis	2,752 (80.21%)	1,667 (67.96%)	1,129 (81.46%)	852 (72.63%)	1	1
福建悬钩子 Rubus fujianensis	434 (12.65%)	579 (23.60%)	133 (9.60%)	159 (13.55%)	2	2
巴东胡颓子 Elaeagnus difficilis	95 (2.77%)	36 (1.47%)	50 (3.61%)	32 (2.73%)	3	5
暗色菝葜 Smilax lanceifolia var. opaca	34 (0.99%)	66 (2.69%)	20 (1.44%)	47 (4.01%)	5	3
草本蕨类植物(前3位) Herbaceous ferns (Top 3)
华东瘤足蕨 Plagiogyria japonica	20,106 (94.25%)	14,477 (88.69%)	1,683 (84.02%)	1,621 (79.27%)	1	1
美观复叶耳蕨 Arachniodes speciosa	746 (3.50%)	479 (2.93%)	162 (8.09%)	80 (3.91%)	2	3
林下凸轴蕨 Metathelypteris hattorii	286 (1.34%)	1,143 (7.00%)	96 (4.79%)	289 (14.13%)	3	2
草质藤本 Herbaceous lianas
鸡屎藤 Paederia foetida	21 (80.77%)	3 (50.00%)	11 (68.75%)	2 (66.67%)	1	1
三叶崖爬藤 Tetrastigma hemsleyanum	5 (19.23%)	3 (50.00%)	5 (31.25%)	1 (33.33%)	2	2
其他草本植物(前5位) Other herbs (Top 5)
薹草属多种 Carex spp.	2,415 (36.88%)	1,570 (38.39%)	715 (45.60%)	412 (40.95%)	1	1
麦冬 Ophiopogon japonicus	2,683 (40.97%)	763 (18.65%)	508 (32.40%)	152 (15.11%)	2	2
山麦冬 Liriope spicata	185 (2.82%)	27 (0.66%)	46 (2.93%)	15 (1.49%)	3	11
求米草 Oplismenus undulatifolius	36 (0.55%)	637 (15.57%)	5 (0.32%)	22 (2.18%)	18	3
异药花 Fordiophyton faberi	111 (1.69%)	333 (8.14%)	36 (2.30%)	50 (4.97%)	4	4
赤车 Pellionia radicans	139 (2.12%)	240 (5.87%)	23 (1.47%)	42 (4.17%)	5	5

物种 Species	株数 Number of individuals		频度 Frequency		重要值排序 Rank of IV
物种 Species	2003	2013	2003	2013	2003	2013
木质藤本植物(前3位) Woody lianas (Top 3)
显脉野木瓜 Stauntonia conspicua	994 (60.98%)	914 (78.12%)	474 (59.62%)	524 (77.86%)	1	1
钻地风 Schizophragma integrifolium	264 (16.19%)	148 (12.65%)	119 (14.97%)	68 (10.10%)	2	2
南五味子 Kadsura longipedunculata	167 (10.25%)	21 (1.79%)	83 (10.44%)	16 (2.38%)	3	3
乔木(前3位) Tree species (Top 3)
短尾柯 Lithocarpus brevicaudatus	3,430 (36.48%)	4,366 (54.22%)	1,288 (26.62%)	1,536 (38.79%)	1	1
多脉青冈 Cyclobalanopsis multinervis	1,716 (18.25%)	1,200 (14.90%)	885 (18.28%)	747 (18.86%)	2	2
木荷 Schima superba	980 (10.42%)	621 (7.71%)	468 (9.67%)	362 (9.18%)	3	3
直立灌木(前5位) Erective shrubs (Top 5)
连蕊茶 Camellia cuspidata	5,894 (13.59%)	4,384 (19.38%)	1,561 (13.18%)	1,558 (16.07%)	1	1
新木姜子 Neolitsea aurata	5,856 (13.51%)	4,318 (14.89%)	1,517 (12.81%)	1,501 (15.22%)	2	2
薄叶山矾 Symplocos anomala	4,560 (10.52%)	1,691 (0.62%)	973 (5.22%)	875 (1.43%)	3	14
叶萼山矾 Symplocos phyllocalyx	795 (1.83%)	4,426 (15.26%)	142 (1.20%)	1,117 (11.33%)	15	3
四川山矾 Symplocos setchuensis	4,032 (9.30%)	2,912 (10.04%)	990 (5.36%)	1,000 (10.14%)	4	4
厚叶红淡比 Cleyera pachyphylla	4,824 (11.13%)	2,114 (7.29%)	525 (4.43%)	592 (6.00%)	5	5
蔓性/攀援灌木(前3位) Spreading shrubs (Top 3)
尖叶菝葜 Smilax arisanensis	2,752 (80.21%)	1,667 (67.96%)	1,129 (81.46%)	852 (72.63%)	1	1
福建悬钩子 Rubus fujianensis	434 (12.65%)	579 (23.60%)	133 (9.60%)	159 (13.55%)	2	2
巴东胡颓子 Elaeagnus difficilis	95 (2.77%)	36 (1.47%)	50 (3.61%)	32 (2.73%)	3	5
暗色菝葜 Smilax lanceifolia var. opaca	34 (0.99%)	66 (2.69%)	20 (1.44%)	47 (4.01%)	5	3
草本蕨类植物(前3位) Herbaceous ferns (Top 3)
华东瘤足蕨 Plagiogyria japonica	20,106 (94.25%)	14,477 (88.69%)	1,683 (84.02%)	1,621 (79.27%)	1	1
美观复叶耳蕨 Arachniodes speciosa	746 (3.50%)	479 (2.93%)	162 (8.09%)	80 (3.91%)	2	3
林下凸轴蕨 Metathelypteris hattorii	286 (1.34%)	1,143 (7.00%)	96 (4.79%)	289 (14.13%)	3	2
草质藤本 Herbaceous lianas
鸡屎藤 Paederia foetida	21 (80.77%)	3 (50.00%)	11 (68.75%)	2 (66.67%)	1	1
三叶崖爬藤 Tetrastigma hemsleyanum	5 (19.23%)	3 (50.00%)	5 (31.25%)	1 (33.33%)	2	2
其他草本植物(前5位) Other herbs (Top 5)
薹草属多种 Carex spp.	2,415 (36.88%)	1,570 (38.39%)	715 (45.60%)	412 (40.95%)	1	1
麦冬 Ophiopogon japonicus	2,683 (40.97%)	763 (18.65%)	508 (32.40%)	152 (15.11%)	2	2
山麦冬 Liriope spicata	185 (2.82%)	27 (0.66%)	46 (2.93%)	15 (1.49%)	3	11
求米草 Oplismenus undulatifolius	36 (0.55%)	637 (15.57%)	5 (0.32%)	22 (2.18%)	18	3
异药花 Fordiophyton faberi	111 (1.69%)	333 (8.14%)	36 (2.30%)	50 (4.97%)	4	4
赤车 Pellionia radicans	139 (2.12%)	240 (5.87%)	23 (1.47%)	42 (4.17%)	5	5

生境 Habitat	与生境负相关的物种数 Number of species positively associated with habitats			与生境正相关的物种数 Number of species negatively associated with habitats
生境 Habitat	2003	2013	差异 Difference	2003	2013	差异 Difference
山谷 Gull	7	5	-2	5	11	6
陡坡 Steep slope	1	1	0	1	1	0
缓坡 Mild slope	1	0	-1	7	4	-3
山脊 Ridge	4	2	-2	4	4	0