摘要: 目的研究沟灌水氮耦合对三倍体毛白杨S86高密度短轮伐期纸浆林林木生长和林分生产力的影响，旨在为选择适合当地的高效沟灌−施肥技术制度提供科学理论依据、�/sec> 方法以山东省高唐县三倍体毛白杨S86为研究对象，采用完全随机区组试验设计，监�?个灌溉水平，即土壤水势值达到−20 kPa（W1）、−33 kPa（W2）、−45 kPa（W3）时开始灌溉，�?个施氮水平（N1�?20 kg/（hm ²·a）；N2�?90 kg/（hm ²·a）；N3�?60 kg/（hm ²·a）；N4�? kg/（hm ²·a））组合下短轮伐期内�?017�?020年）胸径、相对生长率、蓄积、生产力的变化规律，并设置无灌溉施肥作为对照处理（CK）、�/sec> 结果三倍体毛白杨S86的胸径生长速生期持续较长，生长季内各处理不同林龄林分胸径生长均符合Logistic函数＇�i>R ²> 0.99），各沟灌施肥处理的差异主要表现�?月份。沟灌施氮处理对2年生毛白杨S86林木胸径增长量、相对生长率有显著影响（ P< 0.05），而对3 ~5年生毛白杨S86林木影响不显著。水肥耦合措施�? ~ 3年生林木平均蓄积量和平均生产力促进作用较强，而对4 ~5年生林木促进作用不显著。毛白杨S86林木4年的年均生产力为19.65 ~ 25.31 m ³/（hm ²·a），其中年均生产力最大的处理W1N1，显著高于CK 28.41%＇�i>P< 0.05）；5年生林分W1N1处理下林木生长最优，单位面积蓄积和平均生产力分别达到104.39 m ³/hm ²�?7.42 m ³/（hm ²·a），较CK处理分别提高28.15%�?1.74%、�/sec> 结论沟灌水肥耦合措施�? ~ 3年生三倍体毛白杨林木的单位面积蓄积和年度生产力有不同程度的提高，而对4 ~ 5年生毛白杨S86单位面积蓄积和年度生产力无明显作用，其中W1N1沟灌施氮处理生长最优；在气候和土壤条件相近条件下，保持水分充足（灌溉阈值为�?0 kPa）以及较低的施氮量（120 kg/（hm ²·a））时最有利于以纸浆林为培育目标的高密度短轮伐期毛白杨林木的生长、�/sec>

关键诌�
• 三倍体毛白杨S86/
• 沟灌/
• 水肥耦合/
• 林木生长/
• 生产劚�/a>

Abstract: ObjectiveThis paper aims to research the coupling effects of furrow irrigation and nitrogen fertigation on the growth and stand productivity of high-density and short-rotation triploid Populus tomentosaS86 pulp plantations, in order to provide scientific theoretical basis for selecting efficient furrow irrigation-fertilization technology system suitable for the local area. MethodThe plant materials were triploid P. tomentosaS86 in Gaotang County, Shandong Province of eastern China. A completely random block experiment design was adopted to monitor three irrigation levels, i.e. irrigation started when the soil water potential reached �?0 kPa (W1), �?3 kPa (W2) and �?5 kPa (W3), and four fertigation levels (N1, 120 kg/(ha·year); N2, 190 kg/(ha·year); N3, 260 kg/(ha·year); N4, 0 kg/(ha·year)), and the control treatment was with no irrigation and no fertigation set (CK). ResultIt took a long time for the fast-growing period of DBH growth of triploid P. tomentosaS86. The DBH growth of different stand ages in the growing season conformed to the Logistic function ( R ²> 0.99), and the difference of furrow irrigation and fertilization treatments was mainly manifested in June. Nitrogen application in furrow irrigation significantly affected the DBH increment and relative growth rate of 2-year-old P . tomentosaS86 plantations ( P< 0.05), but had no significant effect on 3�?-year-old P. tomentosaS86 plantations. The coupling measures of water and fertilizer had a strong promotion effect on the average volume and average productivity of 2�?-year-old trees, but had no significant promotion effect on 4�?-year-old P . tomentosaS86 plantations. The average annual productivity of triploid P. tomentosaS86 stands was 19.65�?5.31 m ³/(ha·year) in four years, among which, W1N1 had the highest annual productivity, which was significantly higher than CK by 28.41% ( P< 0.05). Under the treatment of 5-year-old stand W1N1, the tree growth was optimal, with unit area volume and average productivity reaching 104.39 m ³/ha and 27.42 m ³/(ha · year), respectively, which were 28.15% and 11.74% higher than CK treatment, respectively. ConclusionThe furrow irrigation and fertilizer coupling measures have different degrees of improvement on the unit area storage and annual productivity of 2�?-year-old triploid P. tomentosaS86 stand, but have no significant effect on the unit area storage and annual productivity of 4�?-year-old P. tomentosaS86 plantation. Among them, W1N1 furrow irrigation and nitrogen application treatment has the best growth. Under similar climatic and soil conditions, maintaining sufficient water (irrigation threshold of �?0 kPa) and a lower nitrogen application rate (120 kg/(ha · year) is most conducive to the growth of high-density short-rotation triploid P . tomentosatargeting pulp forests.

Key words:
• triploidPopulus tomentosaS86/
• furrow irrigation/
• coupling of water and fertilizer/
• tree growth/
• productivity

�?nbsp; 12017�?020年胸径增量变化趋劾�/p>

Figure 1.Changing trend of DBH from 2017 to 2020

下载: 全尺寸图牆�/a> 幻灯牆�/a>

�?nbsp; 22017�?020胸径生长Logistic拟合曲线

Figure 2.Logistic fitting curves of DBH growth in 2017�?020

下载: 全尺寸图牆�/a> 幻灯牆�/a>

�?nbsp; 32017�?020年各处理单位面积蓄积变化

Figure 3.Changes in volume per unit area of each treatment from 2017 to 2020

下载: 全尺寸图牆�/a> 幻灯牆�/a>

�?nbsp; 1不同施氮处理施肥时间和单次施氮量 kg/(hm²·a)

Table 1.Fertilization time of different N application treatments and single N application rate kg/(ha·year)

水平 Level	日期 Date
	04�?0	05�?0	05�?0	06�?9	07�?9	07�?9
N1	24.00	24.00	24.00	16.00	16.00	16.00
N2	38.00	38.00	38.00	25.33	25.33	25.33
N3	52.00	52.00	52.00	34.67	34.67	34.67
N4	0.00	0.00	0.00	0.00	0.00	0.00

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�?nbsp; 2田间试验水氮随机区组设计

Table 2.Random block design of water and nitrogen in field experiment

区组 Block	水肥处理 Water and fertilizer treatment
⅟�/td>	W3N3	W2N3	CK	W1N2	W3N1	W2N4	W2N1	W1N3	W3N2	W3N4	W1N1	W2N2	W1N4
Ⅰ�/td>	W3N2	W1N3	W3N4	W3N1	W3N3	W1N4	W1N2	W1N1	W2N1	W2N4	W2N3	W2N2	CK
Ⅱ�/td>	W3N2	CK	W3N3	W3N4	W3N1	W1N4	W2N3	W2N1	W1N3	W1N1	W2N2	W2N4	W1N2
Ⅲ�/td>	W2N1	W2N2	W1N2	W1N4	W1N1	W3N4	W3N1	W2N3	W2N4	W1N3	W3N2	W3N3	CK
Ⅳ�/td>	W2N3	W3N3	W1N2	W2N1	W1N1	W1N4	W2N2	W2N4	W3N2	CK	W3N1	W1N3	W3N4
注：W1、W2、W3代表土壤水势值分别达到−20、−33、−45 kPa时开始灌溉。下同。Notes: W1, W2 and W3 represent that irrigation will start when the soil water potential reaches �?0, �?3 and �?5 kPa, respectively. The same below.

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�?nbsp; 3各水肥处理下胸径生长Logistic曲线方程参数

Table 3.Parameters of logistic curve equation of DBH growth under various water and fertilizer treatments

年份 Year	处理 Treatment	方程参数 Equation parameter				R2
		A1	A2	x0	p
2017	W1N3	2.998 ± 0.139	6.282 ± 0.252	5.537 ± 0.214	5.818 ± 1.287	0.995
	W1N4	3.006 ± 0.125	5.884 ± 0.257	5.493 ± 0.243	5.803 ± 1.296	0.993
	W3N3	3.041 ± 0.106	6.215 ± 0.310	5.908 ± 0.287	4.643 ± 0.866	0.997
	CK	3.099 ± 0.083	5.724 ± 0.370	6.339 ± 0.437	4.705 ± 1.052	0.995
2018	W1N3	6.122 ± 0.056	8.791 ± 0.065	5.192 ± 0.070	6.596 ± 0.647	0.998
	W1N4	5.876 ± 0.035	8.685 ± 0.042	5.160 ± 0.042	6.843 ± 0.398	0.999
	W3N3	5.838 ± 0.059	8.579 ± 0.054	5.207 ± 0.064	6.706 ± 0.565	0.999
	CK	5.247 ± 0.049	7.939 ± 0.053	5.136 ± 0.058	6.325 ± 0.474	0.999
2019	W1N3	8.650 ± 0.065	10.372 ± 0.072	5.215 ± 0.121	6.426 ± 0.985	0.997
	W1N4	8.455 ± 0.055	10.231 ± 0.057	5.152 ± 0.095	7.170 ± 0.954	0.997
	W3N3	8.434 ± 0.064	10.110 ± 0.050	5.226 ± 0.103	6.823 ± 0.938	0.997
	CK	7.751 ± 0.040	9.514 ± 0.043	5.166 ± 0.072	6.755 ± 0.643	0.999
2020	W1N3	10.295 ± 0.025	11.661 ± 0.025	5.234 ± 0.056	7.261 ± 0.563	0.999
	W1N4	10.173 ± 0.020	11.470 ± 0.016	5.060 ± 0.042	7.614 ± 0.463	0.999
	W3N3	10.061 ± 0.018	11.260 ± 0.012	5.173 ± 0.039	8.294 ± 0.485	0.999
	CK	9.508 ± 0.025	10.811 ± 0.023	5.154 ± 0.057	8.194 ± 0.710	0.999

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�?nbsp; 42017�?020年胸径增量方差分枏�/p>

Table 4.Variance analysis of DBH increment from 2017 to 2020

年份Year	变异来源 Source of variation	df	F	显著�?br/>Significance
2017	区组 Block	4	9.273	< 0.001
	� Water (W)	2	4.637	0.015
	� Nitrogen (N)	3	3.757	0.017
	W × N	6	0.375	0.891
2018	区组 Block	4	1.954	0.118
	W	2	0.012	0.988
	N	3	0.56	0.644
	W × N	6	0.579	0.745
2019	区组 Block	4	1.873	0.132
	W	2	0.279	0.758
	N	3	0.039	0.990
	W × N	6	0.718	0.637
2020	区组 Block	4	3.254	0.020
	W	2	0.597	0.555
	N	3	1.244	0.305
	W × N	6	0.827	0.556

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�?nbsp; 54年的相对增长率方差分枏�/p>

Table 5.Analysis of variance of relative growth rate in 4 years

年份 Year	变异来源 Source of variation	df	F	显著�?br/>Significance
2017	区组 Block	4	1.273	0.295
	W	2	4.970	0.011
	N	3	3.499	0.023
	W × N	6	0.247	0.958
2018	区组 Block	4	11.724	0.000
	W	2	0.899	0.414
	N	3	1.372	0.264
	W × N	6	0.956	0.466
2019	区组 Block	4	5.490	0.001
	W	2	1.119	0.336
	N	3	0.284	0.836
	W × N	6	0.456	0.837
2020	区组 Block	4	7.554	0.000
	W	2	0.261	0.771
	N	3	1.819	0.158
	W × N	6	2.223	0.059

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�?nbsp; 72017�?020年年度蓄积量及生产力

Table 7.Annual volume and productivity in 2017�?020

处理 Treatment	蓄积/（m3·hm�?）Volume /（m3·ha�?（�/td>					平均生产�?（m3·hm�?·a�?（�br/>Average productivity/（m3·ha�?·year�?（�/td>				年均生产�? （m3·hm�?·a�?（�br/>Average annual productivity/ （m3·ha�?·year�?（�/td>
	2017	2018	2019	2020		2017	2018	2019	2020
W1N1	18.65 ± 2.13a	48.43 ± 3.90a	76.97 ± 5.31a	104.39 ± 5.58a		15.51 ± 1.81a	29.78 ± 1.89a	28.53 ± 2.32a	27.42 ± 1.39a	25.31 ± 1.36a
W1N2	17.86 ± 2.31abc	45.06 ± 4.45ab	72.26 ± 7.26a	96.35 ± 8.01a		14.60 ± 1.99ab	27.20 ± 2.31ab	27.20 ± 3.43a	24.09 ± 0.86a	23.27 ± 1.94ab
W1N3	18.20 ± 1.09ab	44.67 ± 2.36abc	70.89 ± 4.76a	98.96 ± 6.94a		15.17 ± 0.92ab	26.47 ± 1.58ab	26.21 ± 2.49a	28.07 ± 2.24a	23.98 ± 1.72a
W1N4	15.90 ± 2.01abcd	44.14 ± 5.08abc	71.17 ± 9.79a	99.01 ± 12.97a		12.84 ± 1.77ab	28.24 ± 3.14ab	27.03 ± 4.91a	27.24 ± 3.87a	23.84 ± 3.31a
W2N1	17.85 ± 1.93abc	45.55 ± 3.01ab	72.27 ± 3.57a	96.74 ± 4.58a		14.58 ± 1.57ab	27.70 ± 1.21ab	26.72 ± 1.88a	24.47 ± 2.21a	23.37 ± 1.13ab
W2N2	13.51 ± 1.94cd	35.94 ± 3.62bc	58.25 ± 5.82a	83.41 ± 8.88a		10.62 ± 1.68ab	22.43 ± 1.88b	22.31 ± 2.34a	25.17 ± 3.15a	20.13 ± 2.17bc
W2N3	16.75 ± 2.07abcd	44.66 ± 4.68abc	73.15 ± 5.16a	102.60 ± 6.62a		13.51 ± 1.89ab	27.91 ± 2.65ab	28.49 ± 1.12a	29.44 ± 1.75a	24.84 ± 1.61a
W2N4	15.61 ± 2.34abcd	41.61 ± 5.66abc	70.21 ± 9.34a	95.37 ± 13.04a		12.37 ± 1.99ab	26.00 ± 3.34ab	28.60 ± 3.82a	25.16 ± 3.87a	23.03 ± 3.18abc
W3N1	17.74 ± 2.57abc	46.04 ± 4.45ab	72.61 ± 5.51a	97.89 ± 5.85a		14.37 ± 2.18ab	28.30 ± 2.04ab	26.57 ± 1.27a	25.27 ± 0.68a	23.63 ± 1.37ab
W3N2	14.95 ± 1.95abcd	40.47 ± 4.11abc	67.08 ± 6.42a	92.48 ± 7.95a		11.87 ± 1.67ab	25.51 ± 2.17ab	26.61 ± 2.46a	25.41 ± 1.89a	22.35 ± 1.92abc
W3N3	16.27 ± 1.95abcd	42.18 ± 3.81abc	66.39 ± 4.11a	89.96 ± 4.28a		13.04 ± 1.63ab	25.92 ± 1.87ab	24.21 ± 1.59a	23.57 ± 0.69a	21.68 ± 1.00abc
W3N4	13.82 ± 2.36bcd	36.22 ± 4.54bc	57.96 ± 5.81a	81.69 ± 6.88a		10.71 ± 1.97ab	22.39 ± 2.26b	21.74 ± 1.90a	23.74 ± 1.42a	19.65 ± 1.64c
CK	12.51 ± 1.21d	34.29 ± 3.57c	57.52 ± 6.77a	81.46 ± 9.80a		9.29 ± 1.01b	21.78 ± 2.52b	23.23 ± 3.81a	24.54 ± 3.49a	19.71 ± 2.52c
注：同列不同小写字母表示处理间差异显著（P< 0.05）。Note: different lowercase letters in the same column indicate significant differences between treatments (P< 0.05).

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