Characteristics of Surface Erosion and Deposition of Sandbag Sand Barriers in Urumqi Sandy Land

doi:10.13304/j.nykjdb.2022.0950

Abstract

Abstract:

The erosion characteristics of sand barrier have important influence on its protective effect. In order to explore the effect of polylactic acid fiber （PLA） sandbag sand barriers on desertification control in Urumqi sandy land， four specifications of poly lactic acid fiber sandbag sand barriers were set with 0.5 m×0.5 m， 1.0 m×1.0 m， 2.0 m×2.0 m and 3.0 m×3.0 m. The concave surface shape inside the baffle was measured by suspension method. The morphological characteristics and erosion effect of concave surface in different specifications of sand barriers were analyzed. The results showed the wind erosion depth at the center of the concave surface of the sand barrier increaseed from 5.17 cm to 21.23 cm with the increase of the sand barrier specifications， and the stacking strength decreased from 3.86 g·cm^-3 to 0.42 g·cm^-3 with the increase of sand barrier size， which the accumulation turned to wind erosion in the barrier. The erosion coefficient was stable at 1/9~1/8， and decreased with the increase of sand barrier size. The deepest point of wind erosion in the barrier moved with the main wind direction. The wind erosion in the direction consistent with the main wind direction was greater， and the opening of the profile curve was larger. The concave surface fitting effect at the top of the slope was better than that at the middle and bottom of the slope. In summary， In Urumqi sandy land， wind erosion occurred mostly in northwest-southeast and west-east directions， the concave surface formed at the top of the slope was more stable， and the area should be suitable for laying 2.0 m×2.0 m PLA sand barriers. Above results could provide scientific reference for the rational application of PLA sand barriers in sand control project in Urumqi sandy land.

Key words: sandbag sand barrier, concave surface, characteristics of erosion and deposition, Urumqi sandy land

摘要：

沙障的蚀积特征对其发挥防护作用具有重要影响。为探究聚乳酸纤维（polylactic acid fiber，PLA）沙袋沙障对乌珠穆沁沙地沙化治理的效果，设置0.5 m×0.5 m、1.0 m×1.0 m、2.0 m×2.0 m和3.0 m×3.0 m共4种规格的聚乳酸纤维沙袋沙障，采用悬测法测量障格内部凹曲面形态，并分析不同规格沙障内部凹曲面的形态特征、蚀积效应。结果表明，沙障凹曲面中心风蚀深度随沙障规格的增大由5.17 cm增加到21.23 cm，而堆积强度随沙障规格的增大由3.86 g·cm^-3降至0.42 g·cm^-3，障格内由堆积变为风蚀；蚀积系数稳定在1/9~1/8，随沙障规格的增大蚀积系数逐渐减小；障格内风蚀最深点随主风向偏移，障格内与主风向一致的方位风蚀量更大，剖面曲线开口更大；坡顶处凹曲面拟合效果大于坡中和坡底。综上所述，在乌珠穆沁沙地内，风蚀多发生在西北-东南和西-东方向上，且坡顶处形成的凹曲面较稳定，该地区适合布设2.0 m×2.0 m规格PLA沙障，研究结果为PLA沙障在乌珠穆沁沙地防沙工程中的合理应用提供了科学参考。

关键词: 沙袋沙障, 凹曲面, 蚀积特征, 乌珠穆沁沙地

CLC Number:

S775

Bonian ZHU, Xiaohong DANG, Zhongju MENG, Yang LIU, Chunhui GUO. Characteristics of Surface Erosion and Deposition of Sandbag Sand Barriers in Urumqi Sandy Land[J]. Journal of Agricultural Science and Technology, 2024, 26(8): 180-188.

朱泊年, 党晓宏, 蒙仲举, 刘阳, 郭春晖. 乌珠穆沁沙地聚乳酸纤维沙袋沙障地表蚀积特征[J]. 中国农业科技导报, 2024, 26(8): 180-188.

Figures/Tables 6

References 21

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规格 Type	位置 Position	凹曲面深度 Concave surface depth/cm	蚀积量 Erosion volume/g	净堆积强度 Net stacking strength/（g·cm^-3）	蚀积系数 Erosion-deposition coefficient
0.5 m×0.5 m	坡顶Upper slope	5.47±0.45 δb	0.09±0.002 4 αb	3.67±0.10 αa	0.11±0.008 2 αa
	坡中Middle slope	5.17±0.59 γa	0.11±0.003 3 αβa	4.34±0.13 αb	0.10±0.012 5 αa
	坡底Bottom slope	5.87±1.48 δab	0.09±0.007 0 βb	3.58±0.31 αb	0.12±0.033 0 αa
1.0 m×1.0 m	坡顶Upper slope	11.03±0.93 βb	0.23±0.051 4 αa	2.33±0.51 βa	0.11±0.008 2 αa
	坡中Middle slope	10.20±1.14 βa	0.17±0.028 0 αab	1.73±0.28 βab	0.10±0.012 5 αa
	坡底Bottom slope	11.50±0.64 γab	0.11±0.037 7 βb	1.06±0.38 βb	0.12±0.004 7 αa
2.0 m×2.0 m	坡顶Upper slope	19.10±1.42 αb	-1.13±0.093 4 βb	-2.83±0.23 δb	0.10±0.009 4 αa
	坡中Middle slope	18.60±1.13 αa	-0.69±0.214 2 γa	-1.74±0.54 δa	0.10±0.004 7 αβa
	坡底Bottom slope	21.00±1.88 αab	-0.73±0.160 8 γab	-1.83±0.40 γab	0.11±0.009 4 αβa
3.0 m×3.0 m	坡顶Upper slope	12.13±2.51 γb	0.13±0.072 1 αb	0.15±0.08 γb	0.04±0.009 4 βb
	坡中Middle slope	21.23±2.72 αa	-0.15±0.078 6 βb	-0.15±0.09 γb	0.07±0.009 4 βa
	坡底Bottom slope	19.97±2.40 βab	1.15±0.322 0 αa	1.27±0.36 βa	0.07±0.004 7 βa

规格 Type	位置 Position	凹曲面深度 Concave surface depth/cm	蚀积量 Erosion volume/g	净堆积强度 Net stacking strength/（g·cm^-3）	蚀积系数 Erosion-deposition coefficient
0.5 m×0.5 m	坡顶Upper slope	5.47±0.45 δb	0.09±0.002 4 αb	3.67±0.10 αa	0.11±0.008 2 αa
	坡中Middle slope	5.17±0.59 γa	0.11±0.003 3 αβa	4.34±0.13 αb	0.10±0.012 5 αa
	坡底Bottom slope	5.87±1.48 δab	0.09±0.007 0 βb	3.58±0.31 αb	0.12±0.033 0 αa
1.0 m×1.0 m	坡顶Upper slope	11.03±0.93 βb	0.23±0.051 4 αa	2.33±0.51 βa	0.11±0.008 2 αa
	坡中Middle slope	10.20±1.14 βa	0.17±0.028 0 αab	1.73±0.28 βab	0.10±0.012 5 αa
	坡底Bottom slope	11.50±0.64 γab	0.11±0.037 7 βb	1.06±0.38 βb	0.12±0.004 7 αa
2.0 m×2.0 m	坡顶Upper slope	19.10±1.42 αb	-1.13±0.093 4 βb	-2.83±0.23 δb	0.10±0.009 4 αa
	坡中Middle slope	18.60±1.13 αa	-0.69±0.214 2 γa	-1.74±0.54 δa	0.10±0.004 7 αβa
	坡底Bottom slope	21.00±1.88 αab	-0.73±0.160 8 γab	-1.83±0.40 γab	0.11±0.009 4 αβa
3.0 m×3.0 m	坡顶Upper slope	12.13±2.51 γb	0.13±0.072 1 αb	0.15±0.08 γb	0.04±0.009 4 βb
	坡中Middle slope	21.23±2.72 αa	-0.15±0.078 6 βb	-0.15±0.09 γb	0.07±0.009 4 βa
	坡底Bottom slope	19.97±2.40 βab	1.15±0.322 0 αa	1.27±0.36 βa	0.07±0.004 7 βa

规格Type	方位Bearing	位置Position	拟合方程Fitting equation	R²
0.5 m×0.5 m	NESW	坡顶Upper slope	Y=0.005 4X² -0.297 9X+8.420 5	0.94
		坡中Middle slope	Y=0.002 9X² -0.123 5X+7.226 4	0.80
		坡底Bottom slope	Y=0.006 6X² -0.431 5X+9.720 9	0.90
	NWSE	坡顶Upper slope	Y=0.003 9X² -0.237 8X+8.077 7	0.87
		坡中Middle slope	Y=0.001 9X² -0.132 3X+8.250 9	0.67
		坡底Bottom slope	Y=0.005 6X² -0.230 9X+5.450 6	0.89
	NS	坡顶Upper slope	Y=0.005 2X² -0.291 8X+8.809 4	0.85
		坡中Middle slope	Y=0.002 4X² -0.105 2X+8.373 7	0.62
		坡底Bottom slope	Y=0.006 8X² -0.313 1X+8.482 8	0.96
	WE	坡顶Upper slope	Y=0.008 1X² -0.460 0X+11.824 0	0.75
		坡中Middle slope	Y=0.004 8X² -0.266 2X+10.111 4	0.50
		坡底Bottom slope	Y=0.007 5X² -0.489 3X+12.308 6	0.44
1.0 m×1.0 m	NESW	坡顶Upper slope	Y=0.002 8X² -0.285 3X+6.534 5	0.95
		坡中Middle slope	Y=0.000 8X² -0.016 8X－0.885 3	0.94
		坡底Bottom slope	Y=0.002 1X² -0.165 0X+1.747 4	0.99
	NWSE	坡顶Upper slope	Y=0.001 1X² -0.122 7X+3.198 8	0.71
		坡中Middle slope	Y=0.001 9X² -0.180 1X+3.338 8	0.83
		坡底Bottom slope	Y=0.002 4X² -0.260 1X+4.909 6	0.98
	NS	坡顶Upper slope	Y=0.002 7X² -0.271 4X+6.843 5	0.87
		坡中Middle slope	Y=0.001 5X² -0.117 2X+2.559 1	0.85
		坡底Bottom slope	Y=0.004 0X² -0.391 7X+8.513 4	0.96
	WE	坡顶Upper slope	Y=0.003 4X² -0.391 4X+13.885 8	0.68
		坡中Middle slope	Y=0.002 9X² -0.287 2X+8.566 4	0.83
		坡底Bottom slope	Y=0.005 1X² -0.530 5X+12.383 7	0.98
2.0 m×2.0 m	NESW	坡顶Upper slope	Y=0.001 2X² -0.279 8X+6.258 5	0.96
		坡中Middle slope	Y=0.001 2X² -0.261 7X+5.486 1	0.93
		坡底Bottom slope	Y=0.001 2X² -0.230 0X+3.048 8	0.92
	NWSE	坡顶Upper slope	Y=-0.000 2X² +0.043 4X-10.955 4	0.22
		坡中Middle slope	Y=0.000 4X² -0.108 9X+0.845 7	0.69
		坡底Bottom slope	Y=0.000 5X² -0.126 1X－0.750 3	0.89
	NS	坡顶Upper slope	Y=0.001 0X² -0.229 4X+6.025 4	0.81
		坡中Middle slope	Y=0.001 0X² -0.219 7X+8.027 7	0.76
		坡底Bottom slope	Y=0.001 2X² -0.258 4X+6.678 5	0.92
	WE	坡顶Upper slope	Y=0.001 6X² -0.353 8X+11.160 3	0.91
		坡中Middle slope	Y=0.001 4X² -0.306 5X+10.874 5	0.72
		坡底Bottom slope	Y=0.001 5X² -0.309 5X+9.783 8	0.80
3.0 m×3.0 m	NESW	坡顶Upper slope	Y=0.000 3X² -0.108X+4.741 2	0.96
		坡中Middle slope	Y=0.000 4X² -0.103 8X-1.329 7	0.53
		坡底Bottom slope	Y=0.000 4X² -0.138 1X+5.625 3	0.87
	NWSE	坡顶Upper slope	Y=0.000 2X² -0.071 7X+4.486 2	0.72
		坡中Middle slope	Y=-0.000 5X² +0.141 9X-10.132 7	0.74
		坡底Bottom slope	Y=0.000 2X² -0.043 6X+5.603 7	0.82
	NS	坡顶Upper slope	Y=0.000 2X² -0.079 0X+5.511 2	0.36
		坡中Middle slope	Y=0.000 2X² -0.102 3X+12.383 0	0.57
		坡底Bottom slope	Y=0.000 4X² -0.158 9X+14.214 3	0.71
	WE	坡顶Upper slope	Y=0.000 4X² -0.130 3X+8.688	0.86
		坡中Middle slope	Y=-0.000 2X² +0.087 9X-9.843 4	0.42
		坡底Bottom slope	Y=0.000 1X² -0.031 8X+3.165 3	0.35

规格Type	方位Bearing	位置Position	拟合方程Fitting equation	R²
0.5 m×0.5 m	NESW	坡顶Upper slope	Y=0.005 4X² -0.297 9X+8.420 5	0.94
		坡中Middle slope	Y=0.002 9X² -0.123 5X+7.226 4	0.80
		坡底Bottom slope	Y=0.006 6X² -0.431 5X+9.720 9	0.90
	NWSE	坡顶Upper slope	Y=0.003 9X² -0.237 8X+8.077 7	0.87
		坡中Middle slope	Y=0.001 9X² -0.132 3X+8.250 9	0.67
		坡底Bottom slope	Y=0.005 6X² -0.230 9X+5.450 6	0.89
	NS	坡顶Upper slope	Y=0.005 2X² -0.291 8X+8.809 4	0.85
		坡中Middle slope	Y=0.002 4X² -0.105 2X+8.373 7	0.62
		坡底Bottom slope	Y=0.006 8X² -0.313 1X+8.482 8	0.96
	WE	坡顶Upper slope	Y=0.008 1X² -0.460 0X+11.824 0	0.75
		坡中Middle slope	Y=0.004 8X² -0.266 2X+10.111 4	0.50
		坡底Bottom slope	Y=0.007 5X² -0.489 3X+12.308 6	0.44
1.0 m×1.0 m	NESW	坡顶Upper slope	Y=0.002 8X² -0.285 3X+6.534 5	0.95
		坡中Middle slope	Y=0.000 8X² -0.016 8X－0.885 3	0.94
		坡底Bottom slope	Y=0.002 1X² -0.165 0X+1.747 4	0.99
	NWSE	坡顶Upper slope	Y=0.001 1X² -0.122 7X+3.198 8	0.71
		坡中Middle slope	Y=0.001 9X² -0.180 1X+3.338 8	0.83
		坡底Bottom slope	Y=0.002 4X² -0.260 1X+4.909 6	0.98
	NS	坡顶Upper slope	Y=0.002 7X² -0.271 4X+6.843 5	0.87
		坡中Middle slope	Y=0.001 5X² -0.117 2X+2.559 1	0.85
		坡底Bottom slope	Y=0.004 0X² -0.391 7X+8.513 4	0.96
	WE	坡顶Upper slope	Y=0.003 4X² -0.391 4X+13.885 8	0.68
		坡中Middle slope	Y=0.002 9X² -0.287 2X+8.566 4	0.83
		坡底Bottom slope	Y=0.005 1X² -0.530 5X+12.383 7	0.98
2.0 m×2.0 m	NESW	坡顶Upper slope	Y=0.001 2X² -0.279 8X+6.258 5	0.96
		坡中Middle slope	Y=0.001 2X² -0.261 7X+5.486 1	0.93
		坡底Bottom slope	Y=0.001 2X² -0.230 0X+3.048 8	0.92
	NWSE	坡顶Upper slope	Y=-0.000 2X² +0.043 4X-10.955 4	0.22
		坡中Middle slope	Y=0.000 4X² -0.108 9X+0.845 7	0.69
		坡底Bottom slope	Y=0.000 5X² -0.126 1X－0.750 3	0.89
	NS	坡顶Upper slope	Y=0.001 0X² -0.229 4X+6.025 4	0.81
		坡中Middle slope	Y=0.001 0X² -0.219 7X+8.027 7	0.76
		坡底Bottom slope	Y=0.001 2X² -0.258 4X+6.678 5	0.92
	WE	坡顶Upper slope	Y=0.001 6X² -0.353 8X+11.160 3	0.91
		坡中Middle slope	Y=0.001 4X² -0.306 5X+10.874 5	0.72
		坡底Bottom slope	Y=0.001 5X² -0.309 5X+9.783 8	0.80
3.0 m×3.0 m	NESW	坡顶Upper slope	Y=0.000 3X² -0.108X+4.741 2	0.96
		坡中Middle slope	Y=0.000 4X² -0.103 8X-1.329 7	0.53
		坡底Bottom slope	Y=0.000 4X² -0.138 1X+5.625 3	0.87
	NWSE	坡顶Upper slope	Y=0.000 2X² -0.071 7X+4.486 2	0.72
		坡中Middle slope	Y=-0.000 5X² +0.141 9X-10.132 7	0.74
		坡底Bottom slope	Y=0.000 2X² -0.043 6X+5.603 7	0.82
	NS	坡顶Upper slope	Y=0.000 2X² -0.079 0X+5.511 2	0.36
		坡中Middle slope	Y=0.000 2X² -0.102 3X+12.383 0	0.57
		坡底Bottom slope	Y=0.000 4X² -0.158 9X+14.214 3	0.71
	WE	坡顶Upper slope	Y=0.000 4X² -0.130 3X+8.688	0.86
		坡中Middle slope	Y=-0.000 2X² +0.087 9X-9.843 4	0.42
		坡底Bottom slope	Y=0.000 1X² -0.031 8X+3.165 3	0.35