Spatial structure characteristics of soil and water conservation forest in the loess area of northern Shaanxi
XIN Yunling1,2, ZHU Qingke1,2, LUO Shuyuan1,2, GOU Qingping1,2
1. School of Soil and Water Conservation, Beijing Forestry University, 100083, Beijing, China; 2. Beijing Forestry University, Engineering Research Center of Forestry Ecological Engineering of the Ministry of Education, 100083, Beijing, China
Abstract:[Background] In the hilly and gully loess region of northern Shaanxi, due to the complicated terrain and insufficient precipitation, the low survival rate of afforestation and serious individual differentiation of some stands have emerged since the implementation of the project of Returning Farmland to Forest. Traditional afforestation planning and design adopted regular plant and row spacing for planting, and there was a big gap between stand state and ideal structure of near-natural stands. The influence of stand space structure on the overall growth status of stands was ignored in the process of afforestation. [Methods] In order to analyze the spatial structure of soil and water conservation forest in the loess area of northern Shaanxi, three plots (each 40 m×40 m) were selected for 3 types of forest (Armeniaca sibirica, Ulmus pumila, Populus hopeiensis forests), with the same site conditions. Taking the southwest corner of the plot as the origin, the spatial coordinates of each tree were obtained. The spatial distribution pattern, degree of differentiation and vertical structure distribution were analyzed. The mingling degree, uniform angle index, neighborhood comparison, open degree, forest layer index, and competition index were selected as the evaluation indexes, and the weight analysis was carried out by AHP, and the evaluation function was finally obtained. [Results] 1) The mean value of all uniform angle exceeded 0.517, and stand distribution patterns were clustered type. The tree size differentiation was as follows: U. pumila > A. sibirica > P. hopeiensis. 2) The mean value of forest layer index was <0.5, indicating that the forest structure was simple and vertical space utilization was low. 3) The competition indexes were all around 0.2, and they were in the transition state of weak competition or weak competition to moderate competition. According to the comprehensive score of plots, the mean value of all kinds of plots was low, and most of them belonged to grade 4 plots. From the perspective of the forest structure, U. pumila was superior to P. hopeiensis, and A.sibirica was the worst. [Conculsions] The spatial structure of soil and water conservation forest stands in the loess area of northern Shaanxi has the problems of single species and unreasonable distribution, thus we should take corresponding measures to solve the problem. The priority of tending is determined according to the evaluation results of stand spatial structure. Strengthening the mixture and stand density is the major measures, and supplemented by the adjustment of individual trees and improving forest stability and health through proper tending.
辛云玲, 朱清科, 罗舒元, 苟清平. 陕北黄土区水土保持林林分空间结构特征[J]. 中国水土保持科学, 2020, 18(5): 17-25.
XIN Yunling, ZHU Qingke, LUO Shuyuan, GOU Qingping. Spatial structure characteristics of soil and water conservation forest in the loess area of northern Shaanxi. SSWC, 2020, 18(5): 17-25.
汤孟平,唐守正,雷相东,等.林分择伐空间结构优化模型研究[J].林业科学,2004, 40(5):25. TANG Mengping, TANG Shouzheng, LEI Xiangdong, et al. Study on spatial structure optimization model of selective cutting in forest stand[J]. Scientia Silvae Sinicae, 2004, 40(5):25
[3]
袁士云,张宋智,刘文桢,等. 小陇山辽东栎次生林的结构特征和物种多样性[J].林业科学,2010,46(5):28. YUAN Shiyun, ZHANG Songzhi, LIU Wenzhen, et al. Structural characteristics and species diversity of secondary forest of Quercus Liaodong in Xiaolongshan[J]. Scientia Silvae Sinicae, 2010, 46(5):28.
[4]
张连金,孙长忠,赖光辉.北京九龙山侧柏生态公益林空间结构分析与评价[J].林业科学研究,2018,31(4):76. ZHANG Lianjin, SUN Changzhong, LAI Guanghui. Spatial structure analysis and evaluation of cypress ecological public welfare forest in Beijing Jiulong mountain[J]. Forest Research, 2008, 31(4):76.
[5]
GADOW K V,FIDNER K.Zur Methodik der Bestandesbeschreibung[R]. Vortrag anlsslich der Jahrestagung der AG Forsteinrichtung,1992:3.
[6]
惠刚盈,VON GADOW K森林空间结构量化分析方法[M].北京:中国科学技术出版社,2003:11. HUI Gangying, VON GADOW K. Quantitative analysis method of forest spatial structure[M]. Beijing:Science and Technology of China Press, 2003:11.
[7]
汤孟平,周国模,陈永刚,等.基于 Voronoi 图的天目山常绿阔叶林混交度[J].林业科学,2009,45(6):1. TANG Mengping, ZHOU Guomo, CHEN Yonggang, et al. The mixing degree of evergreen broad-leaved forest in Tianmu mountain based on Voronoi map[J]. Scientia Silvae Sinicae, 2009, 45(6):1.
[8]
李际平,房晓娜,封尧,等.基于加权Voronoi图的林木竞争指数[J].北京林业大学学报,2015,37(3):61. LI Jiping, FANG Xiaona, FENG Yao, et al. Tree competition inderes based on weighted Voronoi diagram[J]. Journal of Beijing Forestry University, 2015, 37 (3):61.
[9]
曹小玉,李际平.林分空间结构指标研究进展[J].林业资源管理,2016(4):66. CAO Xiaoyu, LI Jiping. Research progress on spatial structure index of stand[J]. Forest Resources Management, 2016(4):66.
[10]
惠刚盈,VON GADOW K,MATTIAS A.一个新的林分空间结构参数:大小比数[J].林业科学研究,1999, 12(1):4. HUI Gangying, VON GADOW K, MATTIAS A. A new spatial structure parameter of stand:Size ratio[J].Forest Research,1999, 12(1):4.
[11]
汤孟平.森林空间结构研究现状与发展趋势[J].林业科学,2010,46(1):117. TANG Mengping. Research status and development trend of forest spatial structure[J]. Scientia Silvae Sinicae,2010,46(1):117.
[12]
吕勇,臧颢,万献军,等.基于林层指数的青椆混交林林层结构研究[J].林业资源管理,2012(3):81. LÜ Yong, ZANG Hao, WAN Xianjun, et al. Based on the index of green Lin mixed forest layer structure study[J]. Forest Resources Management, 2012 (3):81.
[13]
VON GADOW K, HUI G Y. Characterizing forest spatial structure and diversity[C]//Proceedings of the SUFOR International "Sustainable Forestry in Temperate Regions". Lund:University of Lund, 2001:20.
[14]
惠刚盈,胡艳波,赵中华.基于相邻木关系的树种分隔程度空间测度方法[J].北京林业大学学报,2008,30(4):132. HUI Gangying, HU Yanbo, ZHAO Zhonghua. Spatial measurement method of species separation degree based on adjacent wood relationship[J]. Journal of Beijing Forestry University, 2008,30 (4):132.
[15]
惠刚盈,VON GADOW K,AIBERT M.角尺度一个描述林木个体分布格局的结构参数[J].林业科学,1999,35(1):38. HUI Gang ying, VON GADOW K, ALBERT M. A structural parameter describing the distribution pattern of individual trees[J]. Scientia Silvae Sinicae, 1999, 35 (1):38.
[16]
惠刚盈,胡艳波,赵中华,等.基于交角的林木竞争指数[J].林业科学,2013,49(6):70. HUI Gangying, HU Yanbo, ZHAOZhonghua, et al. Competition index of trees based on intersection angle[J].Scientia Silvae Sinicae, 2013,49(6):70.
[17]
曹小玉,李际平,封尧,等.杉木生态公益林林分空间结构分析及评价[J].林业科学,2015,51(7):42. CAO Xiao yu, LI Jiping, FENGYao, et al. Spatial structure analysis and evaluation of Chinese fir ecological public welfare forest[J].Scientia Silvae Sinicae,2015,51(7):42.
张连金,赖光辉,封焕英,等.京西油松生态公益林空间结构评价[J].生态学杂志,2018,37(5):1316. ZHANG Lianjin, LAI Guanghui, FENG Huanying, et al. Spatial structure evaluation of ecological public welfare forest of Pinus japonicus in west Beijing[J]. Chinese Journal of Ecology, 2008, 37(5):1316.
[21]
张连金,孙长忠,赖光辉.北京九龙山侧柏生态公益林空间结构分析与评价[J].林业科学研究,2018,31(4):75. ZHANG Lianjin, SUN Changzhong, LAI Guanghui. Spatial structure analysis and evaluation of cypress ecological public welfare forest in Beijing Jiulong mountain[J]. Forest Research, 2008, 31(4):75.
[22]
孙宇晗,王士博,王润涵,等.利用Voronoi图评价油松人工林空间结构[J].浙江农林大学学报,2018,35(5):877. SUN Yuhan, WANG Shibo, WANG Runhan, et al. Evaluation of spatial structure of Pinus chinensis plantation using Voronoi diagram[J]. Journal of Zhejiang A&F University, 2008, 35(5):877.
[23]
曹小玉,李际平,胡园杰,等.杉木生态林林分间伐空间结构优化模型[J].生态学杂志,2017,6(4):1134. CAO Xiaoyu, LI Jiping, HU Yuanjie, et al. Spatial structure optimization model of forest thinning in Chinese fir ecological forest[J]. Chinese Journal of Ecology, 2017, 36(4):1134.