Spatial distribution pattern and mechanism of sapling regeneration in karst seasonal rainforest in southwestern Guangxi

doi:10.17520/biods.2022251

Abstract

Abstract:

Aims: Saplings are an important component of maintaining the species diversity of forest ecosystems. Their diversity is related to forest community structure and growth dynamics. Therefore, it is very important to study the spatial distribution pattern and potential mechanism of sapling regeneration for forest community dynamics. To strengthen the understanding of the dynamic changes of the northern tropical karst seasonal rainforest, we will study the spatial distribution pattern and mechanism of sapling regeneration in 15 ha northern tropical karst seasonal rainforest dynamics plot in Nonggang, southwestern Guangxi.

Methods: Based on the survey data from 2011 to 2016, the individual number, spatial pattern characteristics, and influencing factors of new saplings (DBH ≥ 1 cm) in five years were analyzed by spatial point pattern and redundancy analysis.

Results: A total of 101 species of new saplings were observed, accounting for 45.3% of the surveyed species in 2011, and the sapling density was 196.5 ind./ha. The newly increased saplings showed aggregated distribution at 0-7 m and 10-16 m scale, and random distribution above 16 m scale. Altitude is the main factor affecting the regeneration of saplings, followed by topographic wetness. Biological factors had a weak impact on sapling regeneration. The number of saplings was negatively correlated with increasing altitude, and positively correlated with topographic wetness. Moderate positive correlation between adult tree individuals and young tree regeneration was observed.

Conclusion: In this karst seasonal rainforest, sapling regeneration and spatial distribution pattern are synergistically affected by various influencing factors, which may be related to limited seed dispersal and habitat heterogeneity.

Key words: karst seasonal rainforest, redundancy analysis, spatial point pattern, sapling regeneration, influencing factors

Ruixia Ma, Yili Guo, Dongxing Li, Bin Wang, Wusheng Xiang, Fuzhao Huang, Fang Lu, Shujun Wen, Jianxing Li, Shuhua Lu, Xiankun Li. Spatial distribution pattern and mechanism of sapling regeneration in karst seasonal rainforest in southwestern Guangxi[J]. Biodiv Sci, 2023, 31(2): 22251.

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URL: https://www.biodiversity-science.net/EN/10.17520/biods.2022251

https://www.biodiversity-science.net/EN/Y2023/V31/I2/22251

Figures/Tables 4

References 51

[1]	Bai DZ (2012) The Impact Factors of Growth and Regeneration of Picea crassifolia Growing at Timberline in the Qilian Mountains. PhD dissertation, Chinese Academy of Forestry, Beijing. (in Chinese with English abstract)
	[白登忠 (2012) 祁连山青海云杉林线树木生长、更新的影响因素研究. 博士学位论文, 中国林业科学研究院, 北京.]
[2]	Cheng Z, Zhou GY, Wu ZM, Wang X, Xie GG, Qiu ZJ, Zhao HB (2015) Biodiversities and distribution patterns of saplings in different forest communities in the Nanling Mountain, southern China. Forest Research, 28, 543-550. (in Chinese with English abstract)
	[程真, 周光益, 吴仲民, 王旭, 谢国光, 邱治军, 赵厚本 (2015) 南岭南坡中段不同群落林下幼树的生物多样性及分布. 林业科学研究, 28, 543-550.]
[3]	Chi S, Wang CJ, Li QJ, Wu ZH, Chai ZZ (2020) Spatial distribution and interspecific associations of regenerating saplings in karst secondary forests. Chinese Journal of Applied Ecology, 31, 3989-3996. (in Chinese with English abstract) DOI
	[池森, 王从军, 黎庆菊, 吴志红, 柴宗政 (2020) 喀斯特次生林幼树更新空间分布格局及种间关联性. 应用生态学报, 31, 3989-3996.] DOI
[4]	Condit R, Ashton PS, Baker P, Bunyavejchewin S, Gunatilleke S, Gunatilleke N, Hubbell SP, Foster RB, Itoh A, LaFrankie JV, Lee HS, Losos E, Manokaran N, Sukumar R, Yamakura T (2000) Spatial patterns in the distribution of tropical tree species. Science, 288, 1414-1418. DOI PMID
[5]	Cousens RD, Wiegand T, Taghizadeh MS (2008) Small-scale spatial structure within patterns of seed dispersal. Oecologia, 158, 437-448. DOI PMID
[6]	Guo K, Liu CC, Dong M (2011) Ecological adaptation of plants and control of rocky-desertification on karst region of Southwest China. Chinese Journal of Plant Ecology, 35, 991-999. (in Chinese with English abstract) DOI
	[郭柯, 刘长成, 董鸣 (2011) 我国西南喀斯特植物生态适应性与石漠化治理. 植物生态学报, 35, 991-999.] DOI
[7]	Guo YL, Wang B, Xiang WS, Ding T, Lu SH, Huang YS, Huang FZ, Li DX, Li XK (2015a) Spatial distribution of tree species in a tropical karst seasonal rainforest in Nonggang, Guangxi, southern China. Biodiversity Science, 23, 183-191. (in Chinese with English abstract) DOI URL
	[郭屹立, 王斌, 向悟生, 丁涛, 陆树华, 黄俞淞, 黄甫昭, 李冬兴, 李先琨 (2015a) 广西弄岗北热带喀斯特季节性雨林监测样地种群空间点格局分析. 生物多样性, 23, 183-191.]
[8]	Guo YL, Wang B, Xiang WS, Ding T, Lu SH, Wen SJ, Huang FZ, Li DX, Li XK (2015b) Sprouting characteristics of tree species in 15 hm² plot of northern tropical karst seasonal rain forest in Nonggang, Guangxi southern China. Chinese Journal of Ecology, 34, 955-961. (in Chinese with English abstract)
	[郭屹立, 王斌, 向悟生, 丁涛, 陆树华, 文淑均, 黄甫昭, 李冬兴, 李先琨 (2015b) 弄岗北热带喀斯特季节性雨林15 hm²样地木本植物萌生特征. 生态学杂志, 34, 955-961.]
[9]	Guo YL, Wang B, Xiang WS, Ding T, Lu SH, Huang FZ, Li DX, Wen SJ, He YL, Li XK (2015c) Density-dependent effects of tree species in a 15 ha seasonal rain forest plot in northern tropical karst in Nonggang, Guangxi, southern China. Chinese Science Bulletin, 60, 1602-1611. (in Chinese with English abstract)
	[郭屹立, 王斌, 向悟生, 丁涛, 陆树华, 黄甫昭, 李冬兴, 文淑均, 何运林, 李先琨 (2015c) 弄岗喀斯特季节性雨林15 ha样地密度制约效应分析. 科学通报, 60, 1602-1611.]
[10]	Guo YL, Wang B, Xiang WS, Ding T, Lu SH, Huang FZ, Wen SJ, Li DX, Li XK (2016) Spatial distribution and habitat-association of snags in the tropical karst seasonal rainforest of Southwest Guangxi, China. Guihaia, 36, 154-161. (in Chinese with English abstract)
	[郭屹立, 王斌, 向悟生, 丁涛, 陆树华, 黄甫昭, 文淑均, 李冬兴, 李先琨 (2016) 桂西南喀斯特季节性雨林枯立木的空间格局及生境关联性分析. 广西植物, 36, 154-161.]
[11]	Harms KE, Condit R, Hubbell SP, Foster RB (2001) Habitat associations of trees and shrubs in a 50-ha neotropical forest plot. Journal of Ecology, 89, 947-959. DOI URL
[12]	Harper JL (1977) Population Biology of Plants. Academic Press, London.
[13]	He FL, Hubbell SP (2011) Species-area relationships always overestimate extinction rates from habitat loss. Nature, 473, 368-371. DOI
[14]	Huang FZ, Ding T, Li XK, Guo YL, Wang B, Xiang WS, Wen SJ, Li DX, He YL (2016) Species diversity for various associations along an altitudinal gradient in the karst seasonal rainforest in Nonggang. Acta Ecologica Sinica, 36, 4509-4517. (in Chinese with English abstract)
	[黄甫昭, 丁涛, 李先琨, 郭屹立, 王斌, 向悟生, 文淑均, 李冬兴, 何运林 (2016) 弄岗喀斯特季节性雨林不同群丛物种多样性随海拔的变化. 生态学报, 36, 4509-4517.]
[15]	Huang FZ, Wang B, Ding T, Xiang WS, Li XK, Zhou AP (2014) Numerical classification of associations in a northern tropical karst seasonal rain forest and the relationships of these associations with environmental factors. Biodiversity Science, 22, 157-166. (in Chinese with English abstract) DOI
	[黄甫昭, 王斌, 丁涛, 向悟生, 李先琨, 周爱萍 (2014) 弄岗北热带喀斯特季节性雨林群丛数量分类及与环境的关系. 生物多样性, 22, 157-166.] DOI
[16]	Huang P, Liu YH (2018) Effects of stand structure and terrain factors on seedling regeneration of Pinus tabuliformis forest in the Songshan National Nature Reserve, Beijing. Chinese Journal of Ecology, 37, 1003-1009. (in Chinese with English abstract)
	[黄萍, 刘艳红 (2018) 北京松山油松林林分结构和地形对幼苗更新的影响. 生态学杂志, 37, 1003-1009.]
[17]	Huang ZL, Peng SL, Yi S (2001) Factors affecting seedling establishment in monsoon evergreen broad-leaved forest. Journal of Tropical and Subtropical Botany, 9, 123-128. (in Chinese with English abstract)
	[黄忠良, 彭少麟, 易俗 (2001) 影响季风常绿阔叶林幼苗定居的主要因素. 热带亚热带植物学报, 9, 123-128.]
[18]	Hubbell SP (2001) The Unified Neutral Theory of Biodiversity and Biogeography. Princeton University Press, Princeton.
[19]	Janzen DH (1970) Herbivores and the number of tree species in tropical forests. The American Naturalist, 104, 501-528. DOI URL
[20]	John R, Dalling JW, Harms KE, Yavitt JB, Stallard RF, Mirabello M, Hubbell SP, Valencia R, Navarrete H, Vallejo M, Foster RB (2007) Soil nutrients influence spatial distributions of tropical tree species. Proceedings of the National Academy of Sciences, USA, 104, 864-869.
[21]	Kanagaraj R, Wiegand T, Comita LS, Huth A (2011) Tropical tree species assemblages in topographical habitats change in time and with life stage. Journal of Ecology, 99, 1441-1452. DOI URL
[22]	Kanno H, Seiwa K (2004) Vegetative reproduction in relation to forest dynamics in the understorey shrub, Hydrangea paniculata (Saxifragaceae). Plant Ecology, 170, 43-53. DOI URL
[23]	Leathwick JR, Mitchell ND (1992) Forest pattern, climate and vulcanism in central north island, New Zealand. Journal of Vegetation Science, 3, 603-616. DOI URL
[24]	Li XK, Jiang ZC, Huang YQ, Xiang WS, Lü SH (2008) Dynamics of dominant population and its influence on karstification in Southwest Guangxi, China. Acta Geoscientica Sinica, 29, 253-259. (in Chinese with English abstract)
	[李先琨, 蒋忠诚, 黄玉清, 向悟生, 吕仕洪 (2008) 桂西南岩溶山地优势植物种群动态及其对岩溶作用的影响. 地球学报, 29, 253-259.]
[25]	Li XK, Su ZM, Lü SH, Ou ZL, Xiang WS, Ou Z, Lu SH (2003) The spatial pattern of natural vegetation in the Karst regions of Guangxi and the ecological signality for ecosystem rehabilitation and reconstruction. Journal of Mountain Research, 21, 129-139. (in Chinese with English abstract)
	[李先琨, 苏宗明, 吕仕洪, 欧祖兰, 向悟生, 区智, 陆树华 (2003) 广西岩溶植被自然分布规律及对岩溶生态恢复重建的意义. 山地学报, 21, 129-139.]
[26]	Li YF, Li XK, Guo YL, Li DX, Wang B, Xiang WS, Huang FZ, Wen SJ, Li JX, Lu SH, Liu SY (2022) Analysis of tree mortality characteristics in a dynamic northern tropical karst seasonal rainforest in Nonggang, Guangxi, southern China. Plant Science Journal, 40, 177-186. (in Chinese with English abstract)
	[李雨菲, 李先琨, 郭屹立, 李冬兴, 王斌, 向悟生, 黄甫昭, 文淑均, 李健星, 陆树华, 刘晟源 (2022) 弄岗北热带喀斯特季节性雨林15 hm²动态监测样地树木死亡特征分析. 植物科学学报, 40, 177-186.]
[27]	Liu SJ, Su ZX (2004) T-square study on spatial pattern and regeneration of Betula albo-sinensis Burkill population on west slope of Jiuding Mountain. Chinese Journal of Applied Ecology, 15, 1-4. (in Chinese with English abstract)
	[刘守江, 苏智先 (2004) 四川九顶山西坡红桦林天然种群空间格局及更新研究. 应用生态学报, 15, 1-4.]
[28]	Ma JM, Liu SR, Shi ZM, Zhang YD, Miao N (2009) Natural regeneration of Abies faxoniana along restoration gradients of subalpine dark coniferous forest in western Sichuan, China. Chinese Journal of Plant Ecology, 33, 646-657. (in Chinese with English abstract) DOI
	[马姜明, 刘世荣, 史作民, 张远东, 缪宁 (2009) 川西亚高山暗针叶林恢复过程中岷江冷杉天然更新状况及其影响因子. 植物生态学报, 33, 646-657.] DOI
[29]	Nyland RD, Bashant AL, Bohn KK, Verostek JM (2006) Interference to hardwood regeneration in northeastern North America: Controlling effects of American beech, striped maple, and hobblebush. Northern Journal of Applied Forestry, 23, 122-132. DOI URL
[30]	Oksanen J, Simpson GL, Guillaume Blanchet F, Kindt R, Legendre P, Minchin PR, O’Hara RB, Solymos P, Stevens MHH, Szoecs E, Wagner H, Barbour M, Bedward S, Evangelista HBA, FitzJohn R, Friendly M, Furneaux B, Hannigan G, Hill MO, Lahti L, McGlinn D, Ouellette MH, Cunha ER, Smith T, Stier A, Ter Braak CJF, Weedon J (2022) vegan: Community Ecology Package. R package version 2.6-2. https://cran.r-project.org/web/packages/vegan/index.html/. (accessed on 2022-03-20)
[31]	Ou YD, Wang HN, Zhang L, Su ZY (2009) Topographic correlates of understory plant species distribution in Nanling National Nature Reserve, Guangdong. Journal of Wuhan Botanical Research, 27, 41-46. (in Chinese with English abstract)
	[区余端, 王华南, 张璐, 苏志尧 (2009) 南岭国家级自然保护区林下植物分布的地形相关性. 武汉植物学研究, 27, 41-46.]
[32]	Peng SJ, Huang ZL, Peng SL, Ouyang XJ, Xu GL (2004) Factors influencing mortality of seed and seedling in plant nature regeneration process. Guihaia, 24, 113-121, 124. (in Chinese with English abstract)
	[彭闪江, 黄忠良, 彭少麟, 欧阳学军, 徐国良 (2004) 植物天然更新过程中种子和幼苗死亡的影响因素. 广西植物, 24, 113-121, 124.]
[33]	Punchi-Manage R, Getzin S, Wiegand T, Kanagaraj R, Gunatilleke CVS, Gunatilleke IAUN, Wiegand K, Huth A (2013) Effects of topography on structuring local species assemblages in a Sri Lankan mixed dipterocarp forest. Journal of Ecology, 101, 149-160. DOI URL
[34]	Schiffers K, Schurr FM, Tielbörger K, Urbach C, Moloney K, Jeltsch F (2008) Dealing with virtual aggregation—A new index for analysing heterogeneous point patterns. Ecography, 31, 545-555. DOI URL
[35]	Silva Matos DM, Freckleton RP, Watkinson AR (1999) The role of density dependence in the population dynamics of a tropical palm. Ecology, 80, 2635-2650. DOI URL
[36]	Su ZM, Mo XL (1988) Geographic distribution of Camellia chrysantha in China. Guihaia, 8, 75-81. (in Chinese with English abstract)
	[苏宗明, 莫新礼 (1988) 我国金花茶组植物的地理分布. 广西植物, 8, 75-81.]
[37]	Tarboton DG (1997) A new method for the determination of flow directions and upslope areas in grid digital elevation models. Water Resources Research, 33, 309-319. DOI URL
[38]	Tilman D (1994) Competition and biodiversity in spatially structured habitats. Ecology, 75, 2-16. DOI URL
[39]	Tilman D, Pecala S (1993) The maintenance of species richness in plant communities. Species Diversity in Ecological Communities, 13-25.
[40]	Valencia R, Foster RB, Villa G, Condit R, Svenning JC, Hernandez C, Romoleroux K, Losos E, Magard K, Balslev EV (2004) Tree species distributions and local habitat variation in the Amazon: Large forest plot in eastern Ecuador. Journal of Ecology, 92, 214-229. DOI URL
[41]	Wang B, Huang YS, Li XK, Xiang WS, Ding T, Huang FZ, Lu SH, Han WH, Wen SJ, He LJ (2014) Species composition and spatial distribution of a 15 ha northern tropical karst seasonal rain forest dynamics study plot in Nonggang, Guangxi, southern China. Biodiversity Science, 22, 141-156. (in Chinese with English abstract) DOI
	[王斌, 黄俞淞, 李先琨, 向悟生, 丁涛, 黄甫昭, 陆树华, 韩文衡, 文淑均, 何兰军 (2014) 弄岗北热带喀斯特季节性雨林15 ha监测样地的树种组成与空间分布. 生物多样性, 22, 141-156.] DOI
[42]	Wang T, Zhang Q, Ma K (2006) Treeline dynamics in relation to climatic variability in the central Tianshan Mountains, northwestern China. Global Ecology and Biogeography, 15, 406-415. DOI URL
[43]	Wang ZQ, Han YZ (2002) Spatial heterogeneity and forest regeneration. Chinese Journal of Applied Ecology, 13, 615-619. (in Chinese with English abstract)
	[王政权, 韩有志 (2002) 森林更新与空间异质性. 应用生态学报, 13, 615-619.]
[44]	Weiner J (1984) Neighbourhood interference amongst Pinus rigida individuals. Journal of Ecology, 72, 183-195. DOI URL
[45]	Wickham H (2016) ggplot2:Elegant Graphics for Data Analysis. Springer-Verlag, New York.
[46]	Wright JS (2002) Plant diversity in tropical forests: A review of mechanisms of species coexistence. Oecologia, 130, 1-14. DOI PMID
[47]	Xiang WS, Li DX, Wang B, Li XK, Guo YL, Wen SJ, Lu SH, Liang SC (2019) Characteristics and spatial distribution of forest gap in a northern tropical karst seasonal rainforest in Nonggang, Guangxi, South China. Guihaia, 39, 87-97. (in Chinese with English abstract)
	[向悟生, 李冬兴, 王斌, 李先琨, 郭屹立, 文淑均, 陆树华, 梁士楚 (2019) 广西弄岗北热带喀斯特季节性雨林林隙特征与空间分布. 广西植物, 39, 87-97.]
[48]	Xie F, Wang SZ (1991) Dynamic studies on regenerated seedlings of evergreen broadleaf forest in Jinggangshan region. Chinese Journal of Applied Ecology, 2, 1-7. (in Chinese with English abstract)
	[谢帆, 王素珍 (1991) 井冈山区常绿阔叶林更新动态的研究. 应用生态学报, 2, 1-7.]
[49]	Yang H, Li YL, Shen L, Kang XG, Yue G, Wang Y (2014) Spatial distribution patterns of seedling and sapling in a spruce-fir forest in the Changbai Mountains area in northeastern China. Acta Ecologica Sinica, 34, 7311-7319. (in Chinese with English abstract)
	[杨华, 李艳丽, 沈林, 亢新刚, 岳刚, 王妍 (2014) 长白山云冷杉林幼苗幼树空间分布格局及其更新特征. 生态学报, 34, 7311-7319.]
[50]	Zhu Y, Mi XC, Ma KP (2009) A mechanism of plant species coexistence: The negative density-dependent hypothesis. Biodiversity Science, 17, 594-604. (in Chinese with English abstract) DOI
	[祝燕, 米湘成, 马克平 (2009) 植物群落物种共存机制: 负密度制约假说. 生物多样性, 17, 594-604.] DOI
[51]	Zhu Y, Getzin S, Wiegand T, Ren HB, Ma KP (2013) The relative importance of Janzen-Connell effects in influencing the spatial patterns at the Gutianshan subtropical forest. PLoS ONE, 8, e74560. DOI URL

排序 Rank	种名 Species	幼树植株数 No. of saplings (2011-2016)	成树植株数 No. of adult plants (2016)
1	对叶榕 Ficus hispida	798	636
2	闭花木 Cleistanthus sumatranus	296	3,824
3	苹婆 Sterculia monosperma	195	3,211
4	垂茉莉 Callicarpa bodinieri	141	18
5	三角车 Rinorea bengalensis	119	390
6	金丝李 Garcinia paucinervis	111	270
7	山榄叶柿 Diospyros siderophylla	86	456
8	割舌树 Dysoxylum mollissimum	84	274
9	蚬木 Excentrodendron tonkinense	81	580
10	海南大风子 Hydnocarpus hainanensis	80	490
11	日本五月茶 Antidesma japonicum	78	316
12	米扬噎 Morus macroura	72	409
13	广西澄广花 Orophea anceps	54	129
14	截裂翅子树 Pterospermum truncatolobatum	52	321
15	南方紫金牛 Sinosideroxylon pedunculatum	44	4
16	山桂花 Bennettiodendron leprosipes	34	1
17	茎花山柚 Gomphandra tetrandra	34	473
18	云南野桐 Mallotus yunnanensis	30	53
19	假肥牛树 Cleistanthus petelotii	30	164
20	网脉核果木 Drypetes perreticulata	29	250
21	肥牛树 Cephalomappa sinensis	28	489
22	弄岗米仔兰 Garuga pinnata	26	160
23	广西棋子豆 Albizia odoratissima	26	200
24	苹果榕 Ficus microcarpa	25	191
25	鱼骨木 Wrightia arborea	21	301
26	乌材 Schefflera lociana	19	183
27	青叶苎麻 Streblus tonkinensis	19	23
28	广西牡荆 Clerodendrum serratum	15	2,918

排序 Rank	种名 Species	幼树植株数 No. of saplings (2011-2016)	成树植株数 No. of adult plants (2016)
1	对叶榕 Ficus hispida	798	636
2	闭花木 Cleistanthus sumatranus	296	3,824
3	苹婆 Sterculia monosperma	195	3,211
4	垂茉莉 Callicarpa bodinieri	141	18
5	三角车 Rinorea bengalensis	119	390
6	金丝李 Garcinia paucinervis	111	270
7	山榄叶柿 Diospyros siderophylla	86	456
8	割舌树 Dysoxylum mollissimum	84	274
9	蚬木 Excentrodendron tonkinense	81	580
10	海南大风子 Hydnocarpus hainanensis	80	490
11	日本五月茶 Antidesma japonicum	78	316
12	米扬噎 Morus macroura	72	409
13	广西澄广花 Orophea anceps	54	129
14	截裂翅子树 Pterospermum truncatolobatum	52	321
15	南方紫金牛 Sinosideroxylon pedunculatum	44	4
16	山桂花 Bennettiodendron leprosipes	34	1
17	茎花山柚 Gomphandra tetrandra	34	473
18	云南野桐 Mallotus yunnanensis	30	53
19	假肥牛树 Cleistanthus petelotii	30	164
20	网脉核果木 Drypetes perreticulata	29	250
21	肥牛树 Cephalomappa sinensis	28	489
22	弄岗米仔兰 Garuga pinnata	26	160
23	广西棋子豆 Albizia odoratissima	26	200
24	苹果榕 Ficus microcarpa	25	191
25	鱼骨木 Wrightia arborea	21	301
26	乌材 Schefflera lociana	19	183
27	青叶苎麻 Streblus tonkinensis	19	23
28	广西牡荆 Clerodendrum serratum	15	2,918

影响因子 Influencing factors	RDA 1	关联性 Association	P	R²_adj
平均海拔 Mean altitude	-0.755641	-	0.001	0.5710
坡度 Slope degree	-0.381791	-	0.001	0.1458
坡向 Aspect	-0.364368	-	0.001	0.1325
原有植株个体数 No. of original plants	-0.416685	-	0.001	0.1736
最大胸径 Maximum diameter at breast height	0.357215	+	0.001	0.1276
地形湿润度指数 Topographic wetness index	0.714364	+	0.001	0.5103
干旱度指数 Altitude above channel	0.006796	+	0.994	0.0000

影响因子 Influencing factors	RDA 1	关联性 Association	P	R²_adj
平均海拔 Mean altitude	-0.755641	-	0.001	0.5710
坡度 Slope degree	-0.381791	-	0.001	0.1458
坡向 Aspect	-0.364368	-	0.001	0.1325
原有植株个体数 No. of original plants	-0.416685	-	0.001	0.1736
最大胸径 Maximum diameter at breast height	0.357215	+	0.001	0.1276
地形湿润度指数 Topographic wetness index	0.714364	+	0.001	0.5103
干旱度指数 Altitude above channel	0.006796	+	0.994	0.0000