广西中南部尾巨桉人工林立地类型划分及立地质量评价

doi:10.11707/j.1001-7488.20210502

摘要/Abstract

摘要：

目的: 对广西中南部丘陵山地尾巨桉无性系人工林进行立地类型划分并进行立地质量评价，为尾巨桉纸浆原料林集约化可持续经营提供科学依据。方法: 采用典型抽样方法，调查1~15年生尾巨桉人工林20 m×20 m的样地94块，采用数量化理论Ⅰ分析林木生长与立地因子的关系，通过层次聚类、降趋对应分析和冗余分析，划分尾巨桉人工林立地类型并进行立地质量评价。结果: 影响广西中南部立地质量的主要因子依次为坡度、土壤类型、土层厚度、土壤密度、坡位和腐残质层厚度；采用坡度、土壤类型和土层厚度3个主导立地因子的组合，划分为11个立地类型，并依据基准年龄6年时的优势木高将其分为Ⅰ~Ⅲ地位级，3个地位级的林分蓄积量达到数量成熟的年龄分别是9、8、7年；Ⅰ地位级为坡度小、赤红壤或砖红壤、土层深厚的高质量立地，基准年龄6年时林分平均高、平均胸径和年均蓄积量分别为22.6 m，14.3 cm和32.09 m³·hm^-2a^-1；Ⅱ地位级为缓坡、砖红壤或红壤、土层厚度中等的立地，基准年龄6年时林分平均树高、平均胸径和年均蓄积量分别为19.1 m，12.7 cm和21.39 m³·hm^-2a^-1；Ⅲ地位级为斜坡或陡坡、红壤或黄壤、土层浅薄质量低的立地，基准年龄6年时林分平均树高、平均胸径和年均蓄积量分别为16.7 m，10.4 cm和12.54 m³·hm^-2a^-1；尾巨桉人工林树高、胸径与土壤全氮、全钾、水解性氮、有效磷、有效钾、有效硼及有机质含量呈极显著正相关（P < 0.01），与pH值、土壤密度呈显著负相关（P < 0.01）。结论: 在适地适树、科学营林的原则下，在营造广西中南部丘陵山地尾巨桉人工林时，应重视立地类型的划分，针对不同地位级的林地应采取测土配方施肥，适当增施氮、磷、钾和硼肥，可显著提高林地生产潜力。

关键词: 尾巨桉, 立地分类, 立地评价, 数量化理论Ⅰ, 冗余分析

Abstract:

Objective: Site classification and quality evaluation of Eucalyptus urophylla×E. grandis plantation in hilly and mountainous region in south-central Guangxi was studied to provide scientific basis for the sustainable management of the plantation for raw material production for pulp-making. Method: Using the typical sampling method, 94 sample plots of the plantations aged between 1 and 15 years were set up. The quantification theory Ⅰ was used to analyze the relationship between tree growth and site factors, and hierarchical clustering analysis, descent correspondence analysis and redundancy analysis were applied to classify the sites and evaluate the site quality. Result: The main factors affecting the site quality in south central Guangxi were slope, soil type, soil layer thickness, soil density, slope position and humus thickness in order. Based on the combination of slope, soil type and soil layer thickness, the site was classified into eleven types, and further divided into Ⅰ-Ⅲ site classes according to the height of dominant tree at the baseline age of 6 years. The age at which the stand volume of the three site classes reach quantitative maturity was 9, 8 and 7 years, respectively. Site class I was a high quality site with low slope, latosolic red soil or laterite and thick soil layer. The mean height, mean diameter at breast height (DBH) and mean annual volume at the baseline age of 6 years were 22.6 m, 14.3 cm and 32.09 m³·hm^-2a^-1, respectively. Site class Ⅱ was a site with gentle slope, laterite or red soil and medium soil thickness. The mean height, mean DBH and mean annual volume at the baseline age of 6 years were 19.1 m, 12.7 cm and 21.39 m³·hm^-2a^-1, respectively. Site class Ⅲ was low quality site with incline slope or steep slope, red soil or yellow soil and thin soil layer. The mean height, mean DBH, and mean annual volume at the baseline age of 6 years were 16.7 m, 10.4 cm and 12.54 m³·hm^-2a^-1, respectively. The height and DBH displayed significant positive correlations with soil total N, total K, hydrolytic N, available P, available K, available B, and content of organic matter, but significant negative correlations with pH value and soil density. Conclusion: Attention should be paid to the classification of site types for E. urophylla×E. grandis plantations in hilly and mountainous region in south central Guangxi with the principles of matching species with the sites and scientific forest management. According to different site classes, fertilization based on soil testing and appropriate addition of N, P, K, and B can significantly improve the production potential of forest land.

Key words: Eucalyptus urophylla×E. grandis, site classification, site evaluation, quantity theory Ⅰ, redundancy analysis

中图分类号:

S758.8

陆海飞,刘望舒,徐建民,李光友,范春节,梁国坚,张磊. 广西中南部尾巨桉人工林立地类型划分及立地质量评价[J]. 林业科学, 2021, 57(5): 13-24.

Haifei Lu,Wangshu Liu,Jianmin Xu,Guangyou Li,Chunjie Fan,Guojian Liang,Lei Zhang. Site Classification and Quality Evaluation of Eucalyptus urophylla×E. grandis Plantation in the South Central Guangxi, China[J]. Scientia Silvae Sinicae, 2021, 57(5): 13-24.

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土壤类型 Soil type	pH	有机质 Soil organic matter/ (g·kg^-¹)	全氮 Total nitrogen/ (g·kg^-1)	全磷 Total phosphorus/ (g·kg^-1)	全钾 Total potassium/ (g·kg^-1)	水解性氮 Hydrolyzable nitrogen/ (mg·kg^-1)	有效磷 Available phosphorus/ (mg·kg^-1)	有效钾 Available potassium/ (mg·kg^-1)	有效锌 Available zinc/ (mg·kg^-1)	有效硼 Available boron/ (mg·kg^-1)	有效铜 Available copper/ (mg·kg^-1)
赤红壤 Latosolic red soil	4.57±0.16	38.28±3.22	1.61±0.20	0.62±0.04	7.52±0.72	114.9±7.14	3.41±0.37	73.5±4.47	2.21±0.25	0.39±0.14	0.74±0.13
砖红壤 Laterite	4.27±0.06	33.21±2.65	1.31±0.14	0.40±0.05	6.12±0.54	108.60±5.98	2.76±0.34	50.37±4.12	2.05±0.19	0.37±0.08	0.71±0.16
红壤 Red soil	4.16±0.08	30.33±2.24	1.17±0.12	0.34±0.03	5.62±0.46	94.43±5.64	1.92±0.27	46.75±4.55	1.65±0.16	0.20±0.06	0.87±0.18
黄壤 Yellow soil	3.89±0.07	16.47±1.76	0.78±0.11	0.28±0.04	2.47±0.19	55.26±4.76	1.79±0.23	25.33±2.89	0.64±0.11	0.11±0.03	1.19±0.14

项目 Item	林龄Age/a
项目 Item	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
平均树高 Mean tree height/m	5.4f	11.4e	13.7d	18.2c	19.8b	21.4a	22.3a	23.1a	23.8a	24.6a	25.2a	25.9a	26.6a	27.1a	27.7a
树高标准差 SD of tree height/m	1.25	1.94	2.09	2.17	2.28	2.31	2.42	2.52	2.59	2.63	2.68	2.78	2.86	2.92	3.01
树高变异系数 CV of tree height (%)	23.15	17.02	15.29	11.92	11.52	10.80	10.85	10.91	10.88	10.69	10.63	10.73	10.75	10.77	10.87

项目 Item	平方和 Sum of square	自由度 Degree of freedom	均方 Mean square	F	P
地貌Landforms	1.26	2	0.63	2.33	0.034
海拔Altitude	0.82	3	0.27	1.14	0.027
坡度Slope	42.44	3	14.15	7.43	0.011
坡位Slope position	5.25	2	2.63	1.38	0.031
土层厚度Soil thickness	18.19	2	9.10	4.77	0.017
坡向Slope aspect	1.77	3	0.59	2.31	0.042
土壤类型Soil type	26.52	3	8.84	4.64	0.015
土壤密度Soil density	8.75	3	2.92	1.53	0.038
腐殖质层厚度Humus thickness	3.86	2	1.93	1.01	0.043
残差Residual	76.32	58	1.32
模型Model	712.62	23	30.98	16.26	0.029
校正计Correction	788.94	81
截距Intercept	2 165.03	1
校正计和截距合计Summary of correction and intercept	2 953.97	82

项目 Item	类目 Category	代码 Code	得分 Score	综合得分及所占比例 Comprehensive score and proportion	偏相关系数 Coefficient of partial correlation
常量项Constant			13.925
地貌 Landforms X₁	台地Tableland	X₁1	0.546	0.715 (6.95%)	0.175^*
	丘陵Hills	X₁₂	0.974
	低山Low mountain	X₁3	0.259
海拔 Altitude X₂/m	< 100	X₂1	0.463	0.588 (5.71%)	0.253^*
	100 ~ 300	X₂₂	0.752
	300 ~ 500	X₂3	0.361
	500 ~ 700	X₂4	0.164
坡度 Slope X₃	平缓坡Conservative slope	X₃1	2.124	2.107 (20.48%)	0.179^**
	缓坡Gentle slope	X₃2	1.073
	斜坡Incline slope	X₃3	0.198
	陡坡Steep slope	X₃4	0.017
坡位 Slope position X₄	上坡Upper slope	X₄₁	0	0.864 (8.39%)	0.255^*
	中坡Middle slope	X₄₂	0.735
	下坡Lower slope	X₄₃	0.864
土层厚度 Soil depth X₅	薄Thin(< 40 cm)	X₅₁	1.091	1.793 (17.42%)	0.367^**
	中Medium (40~80 cm)	X₅₂	2.235
	厚Thick(> 80 cm)	X₅₃	2.884
坡向 Slope aspect X₆	阳坡Sunny slope	X₆1	-1.575	0.743 (7.22%)	0.177^*
	半阳坡Half-sunny slope	X₆2	-1.136
	半阴坡Half-shady slope	X₆3	-0.861
	阴坡Shady slope	X₆4	-0.832
土壤类型 Soil type X₇	赤红壤Latosolic red soil	X₇1	1.497	1.833 (17.81%)	0.472^**
	砖红壤Laterite	X₇2	0.675
	红壤Red soil	X₇3	0.214
	黄壤Yellow soil	X₇4	-0.336
土壤密度 Soil density X₈	> 1.4 g·cm^-3	X₈1	-0.448	0.895 (8.69%)	0.181^*
	1.2 ~ 1.4 g·cm^-3	X₈2	0.364
	1.0 ~ 1.2 g·cm^-3	X₈3	0.137
	< 1.0 g·cm^-3	X₈4	-0.531
腐殖质层厚度 Humus thickness X₉	薄Thin(< 2.0 cm)	X₉₁	0	0.752 (7.31%)	0.269^*
	中Medium(2.0 ~ 4.0 cm)	X₉2	0.614
	厚Thick(> 4.0 cm)	X₉3	0.752

序号 No.	坡度 Slope	土壤类型 Soil type	土层厚度 Thickness of soil/cm	优势木平均树高 Mean height of dominant trees/m
1	平缓坡Conservative slope	赤红壤Latosolic red soil	>80	23.8
2	平缓坡Conservative slope	砖红壤Laterite	>80	22.4
3	平缓坡Conservative slope	红壤Red soil	40 ~ 80	19.5
4	缓坡Gentle slope	红壤Red soil	40 ~ 80	18.5
5	缓坡Gentle slope	赤红壤Latosolic red soil	>80	21.5
6	缓坡Gentle slope	砖红壤Laterite	40 ~ 80	19.2
7	缓坡Gentle slope	砖红壤Laterite	>80	21.1
8	斜坡Incline slope	黄壤Yellow soil	< 40	16.8
9	斜坡Incline slope	红壤Red soil	< 40	17.2
10	陡坡Steep slope	黄壤Yellow soil	< 40	16.3
11	陡坡Steep slope	红壤Red soil	< 40	16.6