Variation of conspecific and heterospecific density-dependent survival along life stages in natural secondary forests in Northeast China

doi:10.17521/cjpe.2023.0293

Abstract

Abstract:

Aims Our aim is to explore density dependence across various life stages trees in temperate forests and determine the varying importance of density dependence at different life stages. We seek to provide a theoretical foundation for species coexistence at a local scale in these forest systems.

Methods Utilizing tree census data and the dynamic monitoring data from 451 seedling quadrats in a 21.12 hm² plot of coniferous and broadleaf mixed forest in Jiaohe, Jilin over three consecutive years (2016-2018), the effects of density dependence on different life stages were analyzed at community and species levels by four models: generalized linear mixed model, generalized linear mixed model incorporating the interaction between individual size and conspecific (heterospecific) neighbor variables, generalized linear mixed model incorporating conspecific neighbor variables and heterospecific neighbor variables as random effects, specialized generalized linear mixed model with sole incorporation of conspecific (heterospecific) neighbor variables as random effects.

Important findings At the community level, conspecific neighbors significantly affected the survival rate across all life stages. Conspecific adult tree neighbors exhibited a significant negative impact on seedling survival rate, while conspecific seedling neighbors had a positive effect on seedling survival rate. The survival of both saplings and adult tree stages was significantly and negatively affected by conspecific neighbors. The Conspecific Negative Density Dependence (CNDD) attenuated in response to life stages. Heterospecific neighbor effects varied in accordance with life stage and neighbor radius, without a well-defined trend. At the species level, the neighborhood effect differed significantly among species solely at the adult tree stage, and neither the conspecific neighborhood effect nor the heterospecific neighborhood effect differed significantly among species at other life stages. Negative density constraints existed in all life stages of this temperate forest, while CNDD decreased with life stage. The effect of heterospecific negative density constraints on the survival rate of individuals in different life stages was influenced by the scale of the neighborhood, without any apparent trend. As a result of the “herd immunity effect” or suitable habitat, the survival of individual seedlings was positively affected by conspecific seedling neighbors. Neighborhood effects varied among species depending on their life history strategies, life types and species richness. The results of this study suggest that the mechanisms affecting the coexistence of species in forest communities at the local scale require comprehensive analyses that incorporate multiple species and life stages.

Key words: density dependence, life stage, neighborhood analysis, Janzen-Connell hypothesis

QIANG Ya-Qi, ZHANG Xin-Na, WANG Juan, ZHANG Chun-Yu. Variation of conspecific and heterospecific density-dependent survival along life stages in natural secondary forests in Northeast China[J]. Chin J Plant Ecol, 2024, 48(12): 1612-1622.

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URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2023.0293

https://www.plant-ecology.com/EN/Y2024/V48/I12/1612

Figures/Tables 7

References 41

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物种 Species	幼苗 Seedling		幼树 Sapling		成树 Adult		DBH ≥ 1 cm个体数 No. of stems of DBH ≥ 1 cm
物种 Species	个体数 Individual No.	平均基径 Average BD (cm)	个体数 Individual No.	平均胸径 Average DBH (cm)	个体数 Individual No.	平均胸径 Average DBH (cm)	DBH ≥ 1 cm个体数 No. of stems of DBH ≥ 1 cm
白桦 Betula platyphylla	-	-	-	-	279	27.90	279
东北槭 Acer mandshuricum	144	4.40	2 157	2.57	3 651	12.79	5 808
暴马丁香 Syringa reticulata var. amurensis	-	-	670	2.75	1 095	5.74	1 765
稠李 Padus racemosa	-	-	125	2.41	292	6.59	417
春榆 Ulmus davidiana var. japonica	9	4.43	657	4.39	862	19.34	1 519
髭脉槭 Acer barbinerve	114	6.07	1 170	1.88	825	3.51	1 995
大果榆 Ulmus macrocarpa	-	-	109	4.54	221	25.32	330
硕桦 Betula costata	-	-	32	8.09	444	28.66	476
黑樱桃 Cerasus maximowiczii	-	-	31	3.00	30	28.60	61
红松 Pinus koraiensis	193	1.82	201	5.11	2 118	31.82	2 319
胡桃楸 Juglans mandshurica	43	4.58	34	2.85	1 940	8.50	1 974
朝鲜槐 Maackia amurensis	-		36	4.66	111	13.54	147
黄檗 Phellodendron amurense	2	6.01	36	5.73	153	23.73	189
辽椴 Tilia mandshurica	10	5.50	94	6.70	419	24.05	513
裂叶榆 Ulmus laciniata	28	8.01	1 189	4.42	680	23.42	1 869
瘤枝卫矛 Euonymus verrucosus	-	-	30	1.96	41	3.54	71
毛榛 Corylus mandshurica	-	-	480	1.83	308	2.92	788
蒙古栎 Quercus mongolica	1	1.97	144	6.85	626	32.45	770
三花槭 Acer triflorum	2	1.30	270	4.03	539	20.93	809
千金榆 Carpinus cordata	30	3.35	3 562	3.55	5 458	10.30	9 020
青楷槭 Acer tegmentosum	4	6.10	225	5.06	195	13.86	420
色木槭 Acer mono	233	2.61	3 864	3.50	4 319	20.74	8 183
杉松 Abies holophylla	38	1.88	116	5.27	341	32.88	457
山荆子 Malus baccata	-	-	50	3.54	30	14.33	80
山杨 Populus davidiana	-	-	-	-	51	34.44	51
水曲柳 Fraxinus mandschurica	1 786	1.42	89	7.44	1 948	30.51	2 037
水榆花楸 Sorbus alnifolia	-	-	245	4.21	351	17.20	596
香杨 Populus koreana	-	-	-	-	49	54.64	49
紫椴 Tilia amurensis	312	1.36	494	6.58	1 898	27.66	2 392
合计 Total	2 949	3.80	16 110	3.51	29 274	19.45	45 384

物种 Species	幼苗 Seedling		幼树 Sapling		成树 Adult		DBH ≥ 1 cm个体数 No. of stems of DBH ≥ 1 cm
物种 Species	个体数 Individual No.	平均基径 Average BD (cm)	个体数 Individual No.	平均胸径 Average DBH (cm)	个体数 Individual No.	平均胸径 Average DBH (cm)	DBH ≥ 1 cm个体数 No. of stems of DBH ≥ 1 cm
白桦 Betula platyphylla	-	-	-	-	279	27.90	279
东北槭 Acer mandshuricum	144	4.40	2 157	2.57	3 651	12.79	5 808
暴马丁香 Syringa reticulata var. amurensis	-	-	670	2.75	1 095	5.74	1 765
稠李 Padus racemosa	-	-	125	2.41	292	6.59	417
春榆 Ulmus davidiana var. japonica	9	4.43	657	4.39	862	19.34	1 519
髭脉槭 Acer barbinerve	114	6.07	1 170	1.88	825	3.51	1 995
大果榆 Ulmus macrocarpa	-	-	109	4.54	221	25.32	330
硕桦 Betula costata	-	-	32	8.09	444	28.66	476
黑樱桃 Cerasus maximowiczii	-	-	31	3.00	30	28.60	61
红松 Pinus koraiensis	193	1.82	201	5.11	2 118	31.82	2 319
胡桃楸 Juglans mandshurica	43	4.58	34	2.85	1 940	8.50	1 974
朝鲜槐 Maackia amurensis	-		36	4.66	111	13.54	147
黄檗 Phellodendron amurense	2	6.01	36	5.73	153	23.73	189
辽椴 Tilia mandshurica	10	5.50	94	6.70	419	24.05	513
裂叶榆 Ulmus laciniata	28	8.01	1 189	4.42	680	23.42	1 869
瘤枝卫矛 Euonymus verrucosus	-	-	30	1.96	41	3.54	71
毛榛 Corylus mandshurica	-	-	480	1.83	308	2.92	788
蒙古栎 Quercus mongolica	1	1.97	144	6.85	626	32.45	770
三花槭 Acer triflorum	2	1.30	270	4.03	539	20.93	809
千金榆 Carpinus cordata	30	3.35	3 562	3.55	5 458	10.30	9 020
青楷槭 Acer tegmentosum	4	6.10	225	5.06	195	13.86	420
色木槭 Acer mono	233	2.61	3 864	3.50	4 319	20.74	8 183
杉松 Abies holophylla	38	1.88	116	5.27	341	32.88	457
山荆子 Malus baccata	-	-	50	3.54	30	14.33	80
山杨 Populus davidiana	-	-	-	-	51	34.44	51
水曲柳 Fraxinus mandschurica	1 786	1.42	89	7.44	1 948	30.51	2 037
水榆花楸 Sorbus alnifolia	-	-	245	4.21	351	17.20	596
香杨 Populus koreana	-	-	-	-	49	54.64	49
紫椴 Tilia amurensis	312	1.36	494	6.58	1 898	27.66	2 392
合计 Total	2 949	3.80	16 110	3.51	29 274	19.45	45 384

模型类型 Model type	模型表达式 Model expression	固定效应 Fixed effect	随机效应 Random effect
基础模型 Basic model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD
引入交互作用的模型 Interaction model	$\begin{align} & {{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3}}\times \text{HE}{{\text{T}}_{ijk}}+ \\ & \ \ \ \ \ \ \ {{\beta }_{4}}\times \text{CO}{{\text{N}}_{ijk}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{5}}\times \text{HE}{{\text{T}}_{ijk}}\times \text{siz}{{\text{e}}_{ijk}}+{{\phi }_{l}} \\ \end{align}$	DBH, Con, Het, Con × DBH, Het × DBH	Species identity, Quadrat, DBH/BD
引入物种间随机效应的模型 Random effects model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2j}}\times \text{CO}{{\text{N}}_{ijk}}+\ {{\beta }_{3j}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD, Con, Het
单独引入物种间随机效应的模型 Individual random effects model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2j}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD, Con/Het
单独引入物种间随机效应的模型 Individual random effects model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3j}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD, Con/Het

模型类型 Model type	模型表达式 Model expression	固定效应 Fixed effect	随机效应 Random effect
基础模型 Basic model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD
引入交互作用的模型 Interaction model	$\begin{align} & {{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3}}\times \text{HE}{{\text{T}}_{ijk}}+ \\ & \ \ \ \ \ \ \ {{\beta }_{4}}\times \text{CO}{{\text{N}}_{ijk}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{5}}\times \text{HE}{{\text{T}}_{ijk}}\times \text{siz}{{\text{e}}_{ijk}}+{{\phi }_{l}} \\ \end{align}$	DBH, Con, Het, Con × DBH, Het × DBH	Species identity, Quadrat, DBH/BD
引入物种间随机效应的模型 Random effects model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2j}}\times \text{CO}{{\text{N}}_{ijk}}+\ {{\beta }_{3j}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD, Con, Het
单独引入物种间随机效应的模型 Individual random effects model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2j}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD, Con/Het
单独引入物种间随机效应的模型 Individual random effects model	${{S}_{ijk}}={{\beta }_{0j}}+{{\beta }_{1j}}\times \text{siz}{{\text{e}}_{ijk}}+{{\beta }_{2}}\times \text{CO}{{\text{N}}_{ijk}}+{{\beta }_{3j}}\times \text{HE}{{\text{T}}_{ijk}}+{{\phi }_{l}}$	DBH/BD, Con, Het	Species identity, Quadrat, DBH/BD, Con/Het

生物邻体变量 Biological neighborhood variable	邻域半径 Neighbor radius (m)	AIC	ΔAIC
幼苗邻体变量_1 Seedling_1	5	1 991.4	-1.3
	10	1 992.0	-0.7
	15	1 992.7	0.0
	20	1 994.2	1.5
幼苗邻体变量_2 Seedling_2	5	1 992.9	0.3
	10	1 993.8	1.2
	15	1 992.6	0.0
	20	1 995.2	2.6
幼苗邻体变量_3 Seedling_3	1	1 991.8	0.0
幼树邻体变量 Sapling	5	17 173.4	2.5
	10	17 172.0	1.1
	15	17 170.9	0.0
	20	17 164.2	-6.7
成树邻体变量 Adult	5	17 892.6	4.0
	10	17 889.0	0.4
	15	17 888.6	0.0
	20	17 895.5	6.9