宁夏黄土梁状丘陵区六种稀疏人工林的枯落物持水特征

doi:10.11707/j.1001-7488.20221108

摘要/Abstract

摘要：

目的: 枯落物层持水性能是林地水文效应评价的重要内容，定量评价黄土梁状丘陵区比较稀疏的典型人工林枯落物层的水文特征指标，可为研究区林草植被的生态重建、结构优化等提供理论依据。方法: 选择山杏、山桃、柠条纯林与山杏-沙棘混交林、山杏-柠条混交林、山桃-山杏-苜蓿混交林6种人工林，分别设置20 m×20 m的标准样地，在四角及中心设5个1 m×1 m的样方收集枯落物样品。采用野外调查和室内浸泡法，分析保存在地表及混入土壤中的所有枯落物的蓄积量、持水性及持水动态变化规律。结果: 研究表明：1）6种林分枯落物总蓄积量范围在1.05~4.01 t·hm^-2，其中山杏纯林最高，山桃纯林最低。土壤中枯落物蓄积量占枯落物总蓄积量的比例变化范围在11.43%~25.00%。除山杏纯林外，混交林分的总蓄积量均大于纯林。2）综合6种林分地表枯落物和土壤中枯落物的持水能力来看，最大持水量为山杏纯林（15.75 t·hm^-2），最大持水率为山杏-柠条混交林（264.65%）。3）6种林分枯落物的持水量和吸水速率的动态变化过程均表现为在浸水初期迅速变化，24 h时达到饱和趋于稳定。持水量和持水速率随浸泡时间的变化分别符合自然对数方程和幂函数方程，均达到极显著水平（P < 0.01）。4）综合分析了6种林分枯落物的有效拦蓄量和有效拦蓄率变化，结果显示山杏纯林地表枯落物的拦蓄能力最高，山杏-柠条混交林土壤中枯落物的拦蓄能力最高；山杏纯林的总有效拦蓄量最高（11.08 t·hm^-2），山杏-柠条混交林次之（7.67 t·hm^-2）。结论: 在宁夏黄土梁状丘陵区，6种稀疏人工林的枯落物持水性能综合表现为山杏纯林及山杏-柠条混交林优于其他林分。研究结果可为当地生态恢复中的枯落物水土保持效益科学评价和林草植被结构优化提供理论依据。

关键词: 黄土梁状丘陵区, 稀疏人工林, 枯落物, 持水特征

Abstract:

Objective: Water-holding capacity of litter layer is an important part for hydrological effect evaluation of forest land. Quantitative evaluation of hydrological characteristics of litter layer of typical sparse plantations in Loess ridge hilly region can provide a theoretical basis for ecological reconstruction and structure optimization of forest and grass vegetation in the study area. Method: Six kinds of artificial forests were selected, including pure forest of Armeniaca sibirica, Amygdalus davidiana, and Caragana intermedia, A.sibirica and Hippophae rhamnoides mixed forest, A. sibirica and C. intermedia mixed forest, and A. sibirica, A. davidiana and Medicago sativa mixed forest. A standard plot of 20 m×20 m was set up in each of artificial forests, and five subplots of 1 m×1 m were set up at the four corners and the center of the plot to collect litter samples. The field investigation and indoor soaking method were used to compare and analyze the stock volume, water-holding capacity and dynamic change pattern of all litter on the surface and mixed with soil in each of artificial forests. Result: The result showed that: 1) The total litter volume of the six artificial forests ranged from 1.05 t·hm^-2 to 4.01 t·hm^-2, with the highest in pure forest of A. sibirica and the lowest in pure forest of A. davidiana. The proportion of litter volume in soil to total litter volume varied from 11.43% to 25.00%. Except for pure forest of A. sibirica, the total volume of the mixed forest was all greater than that of the pure forest. 2) In terms of the water-holding capacity of the surface litter and the litter in the soil of the six kinds of artificial forests, the maximum water-holding capacity of A. sibirica pure forest was the highest (15.75 t·hm^-2), and the maximum water-holding rate of A. sibirica and C.intermedia mixed forest was the highest (264.65%). 3) During the water absorption prosess, the dynamic changes in litter water-holding capacity and water absorption rate in the six kinds of artificial forests changed rapidly at the early immersion stage, reached saturation and tended to be stable at 24 hours. The variation of water-holding capacity and water absorption rate were in accordance with the natural logarithm equation and power fuction equation, respectively, and reached a very significant level (P < 0.01). 4) In terms of the effective water retention capacity and effective water retention rate of the six stands, the surface litter of A. sibirica pure forest had the strongest effective water retention capacity, and the soil litter of A. sibirica and C.intermedia mixed forest had the strongest effective water retention capacity. The total effective water retention capacity of litter in A. sibirica pure forest was the highest (11.08 t·hm^-2), followed by A. sibirica and C.intermedia mixed forest (7.67 t·hm^-2). Conclusion: In the Loess ridge hilly region of Ningxia, the comprehensive performance of litter water holding capacity of A. sibirica pure forest, and A. sibirica and C. intermedia mixed forest is better than that of the other stands. The result can provide a theoretical basis for the scientific evaluation of soil and water conservation benefits of litter and the optimization of forest and grass vegetation structure in local ecological restoration.

Key words: loess beam-shaped hilly area, sparse plantation, litter, water-holding characteristics

中图分类号:

S715.3

蔡进军,李维倩,陈刚,白阳阳,吴霞,王天宁,吴艳,盛浪,张兴昌. 宁夏黄土梁状丘陵区六种稀疏人工林的枯落物持水特征[J]. 林业科学, 2022, 58(11): 83-95.

Jinjun Cai,Weiqian Li,Gang Chen,Yangyang Bai,Xia Wu,Tianning Wang,Yan Wu,Lang Sheng,Xingchang Zhang. Water-Holding Characteristics of the Litter Layer of Six Sparse Plantation Types in the Loess Ridge Hilly Region of Ningxia[J]. Scientia Silvae Sinicae, 2022, 58(11): 83-95.

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林分类型 Stand type	坡向 Slope aspect	坡位 Slope position	坡度 Slope/(°)	海拔 Altitude/m	林龄 Forest age/a	密度 Density/(plant·hm^-2)	株高 Average tree height/m	地径 Average DBH/cm	郁闭度 Canopy density
山杏A. sibirica	NW 50°	中下坡 Middle-down slope	12.25	1 648.42	20	675	4.08±0.09	12.45±0.08	0.28
山桃A. davidiana	NW 76°	中坡 Middle slope	11.29	1 673.82	19	<382>	<3.60±0.06>	<4.45±0.08>	<0.26>
柠条C. intermedia	NW 74°	中坡 Middle slope	15.45	1 649.41	15	<1 576>	<2.92±0.23>	<2.17±0.17>	<0.31>
山杏-沙棘 A. sibirica - H. rhamnoides	SW 76°	中坡 Middle slope	22.89	1 674.09	20	375 <2 255>	3.45±0.88 <1.01±0.03>	9.97±0.22 <1.65±0.29>	0.29 <0.69>
山杏-柠条 A. sibirica - C. intermedia	SE 48°	中坡 Middle slope	22.32	1 660.06	20	550 <1 125>	4.45±0.13 <1.41±0.07>	10.30±0.67 <1.51±0.17>	0.30 <0.66>
山杏-山桃-苜蓿 A. sibirica - A. davidiana-M. sativa	NE 43°	中坡 Middle slope	17.58	1 583.82	18	521 <143>	3.38±0.15 <3.07±0.14> (0.76±0.11)	11.25±0.37 <4.20±0.50>	0.33 <0.25> (0.71)

林分类型 Stand type	枯落物层覆盖度 Coverage (%)	地表枯落物Surface litter		土壤中枯落物Litter in soil		枯落物总蓄积量 Total litter volume/(t·hm^-2)
林分类型 Stand type	枯落物层覆盖度 Coverage (%)	厚度 Thickness/cm	蓄积量 Volume of litter/(t·hm^-2)	混入深度 Depth/cm	蓄积量 Volume of litter/(t·hm^-2)	枯落物总蓄积量 Total litter volume/(t·hm^-2)
山杏A. sibirica	83.8±3.89a	2.60±0.89a	3.46±1.21a	0.42±0.13a	0.55±0.15a	4.01±1.27a
山桃A. davidiana	43.8±10.35c	2.30±0.75bc	0.93±0.63c	0.36±0.13a	0.12±0.04c	1.05±0.65c
柠条C. intermedia	67.4±8.98b	2.40±0.55bc	1.08±0.14c	0.30±0.07a	0.15±0.04c	1.23±0.15c
山杏-沙棘A. sibirica - H. rhamnoides	73.4±12.36ab	2.26±0.70bc	2.04±0.30b	0.30±0.07a	0.47±0.15ab	2.51±0.23b
山杏-柠条A. sibirica - C.intermedia	59.4±12.21b	2.36±0.52bc	1.26±0.54bc	0.30±0.01a	0.42±0.15ab	1.68±0.53bc
山杏-山桃-苜蓿A. sibirica - A. davidiana-M.sativa	59.0±11.40b	1.56±0.44b	1.13±0.40c	0.32±0.13a	0.33±0.06b	1.46±0.36c

林分类型 Stand type	地表枯落物 Surface litter	相关系数 R²	土壤中枯落物 Litter in soil	相关系数 R²
山杏A. sibirica	K=369.409 lnt+1 332.267	0.920	K=314.943 lnt+1 117.797	0.945
山桃A. davidiana	K=470.671 lnt+1 208.661	0.933	K=275.559 lnt+1 027.696	0.989
柠条C.intermedia	K=541.102 lnt+1 193.896	0.947	K=255.415 lnt+1 121.858	0.924
山杏-沙棘A. sibirica-H.rhamnoides	K=715.510 lnt+1 100.801	0.990	K=250.513 lnt+1 066.169	0.961
山杏-柠条A. sibirica-C.intermedia	K=722.585 lnt+1 194.272	0.949	K=356.187 lnt+1 113.235	0.964
山桃-山杏-苜蓿A. sibirica-A. davidiana-M.sativa	K=731.866 lnt+1 073.211	0.984	K=264.067 lnt+1 089.704	0.952

林分类型 Stand type	地表枯落物 Surface litter	相关系数 R²	土壤中枯落物 Litter in soil	相关系数 R²
山杏A. sibirica	B=21 185.386 t^-3.275	0.902	B=13 327.706 t^-3.313	0.933
山桃A. davidiana	B=33 580.310 t^-3.884	0.891	B=9 304.245 t^-3.069	0.902
柠条C.intermedia	B=41 261.582 t^-4.012	0.876	B=8 302.763 t^-3.175	0.961
山杏-沙棘A. sibirica-H.rhamnoides	B=38 525.957 t^-3.587	0.837	B=5 200.827 t^-2.785	0.981
山杏-柠条A. sibirica-C.intermedia	B=57 641.837 t^-4.026	0.888	B=12 975.541 t^-3.313	0.919
山桃-山杏-苜蓿A. sibirica-A. davidiana-M.sativa	B=39 558.515 t^-3.600	0.861	B=6 524.832 t^-2.973	0.968

林分类型 Stand type	地表枯落物Surface litter		土壤中枯落物Litter in soil		总有效拦蓄量 Total retaining content/(t·hm^-2)	平均有效拦蓄率 Average Effective retaining rate (%)
林分类型 Stand type	有效拦蓄量Effective retaining content/(t·hm^-2)	有效拦蓄率Effective retaining rate (%)	有效拦蓄Effective retaining content/(t·hm^-2)	有效拦蓄率Effective retaining rate (%)	总有效拦蓄量 Total retaining content/(t·hm^-2)	平均有效拦蓄率 Average Effective retaining rate (%)
山杏 A. sibirica	7.67±2.11a	227.41	3.41±1.30ab	183.80	11.08±2.59a	205.60
山桃纯林 A. davidiana	1.74±1.04c	196.77	2.16±0.56b	124.68	3.90±1.15c	160.72
柠条C.intermedia	2.14±0.48c	198.07	2.32±0.37b	132.60	4.46±0.66c	165.33
山杏-沙棘 A. sibirica-H.rhamnoides	2.80±1.40bc	195.91	2.50±0.38ab	125.15	5.30±0.64b	160.53
山杏-柠条混交林 A. sibirica-C.intermedia	3.99±0.80b	216.40	3.68±0.74a	153.91	7.67±1.12b	185.15
山桃-山杏-苜蓿混交林A. sibirica-A. davidiana-M.sativa	2.24±0.92c	195.02	2.71±0.72ab	135.56	4.95±1.02bc	165.29