Breakage of soil aggregates during saltation is one process that contributes to the generation of fine dust emissions by wind erosion. Fine dust is also known to affect human respiratory health. Of particular hazard are particles of aerodynamic diameter less than 2.5 μm (PM2.5) and those less than 10 μm (PM10), both of which are regulated by the US-Environmental Protection Agency. We used a laboratory wind tunnel with wind at 13 m s⁻¹ to investigate the emission parameters for PM2.5 and PM10 caused by saltation-size aggregates (0.15 to 0.84 mm) from 15 soils with a wide range in properties from across the U.S. The coefficient of breakage (C_bk) was found to vary inversely with clay content, with the largest values found for soils with the greatest sand content. Only one soil with the highest sand content was found to be statistically different in total suspension flux from breakage (Gss_bk). We did not find a relationship between soil texture or organic matter and the soil fraction of PM2.5 and PM10 from breakage (SF2.5_bk and SF10_bk). In addition, five of the soils tested had long-term histories of either conventional tillage (CT) or no-till (NT) management for paired comparisons of emission based on management. CT soils tended to have higher sand, lower silt and lower organic matter than NT management. Management significantly affected C_bk for four of the five soil pairs where the three with the highest clay content having lower C_bk under NT than CT management and the fourth pair had lower C_bk under CT management. Long-term NT management showed significantly less vertical suspension flux from breakage during saltation (Gss_bk) than CT management for only two of the five paired soils. A linear relationship predicted PM2.5 emissions from breakage as a fraction of PM10 emissions for the mineral soils tested (R² = 0.972). This research contributes to our understanding of PM2.5 and PM10 emission during saltation. It also provides parameters that will improve fine dust simulation in the Wind Erosion Prediction System (WEPS) model.

盐分过程中土壤聚集体的破裂是一种因风蚀而导致产生细粉尘的过程。还已知细粉尘会影响人体呼吸健康。特别危险的是空气动力学直径小于2.5μm（PM2.5）的颗粒和小于10μm（PM10）的颗粒，这两种颗粒均受美国环境保护署监管。我们使用了一个风速为13 ms ^-1的实验室风洞，研究了美国15个土壤性质各异的盐分大小的聚集体（0.15至0.84 mm）引起的PM2.5和PM10的排放参数。破损系数（C _bk）被发现与粘土含量成反比，最大的沙含量的土壤发现最大的值。发现只有一种含沙量最高的土壤在总悬浮液通量和破损量之间存在统计学差异（Gss _bk）。我们没有发现土壤质地或有机质与破损的PM2.5和PM10的土壤分数（SF2.5 _bk和SF10 _bk）之间的关系。此外，测试的土壤中有五种具有常规耕作（CT）或免耕（NT）管理的长期历史，用于基于管理的排放成对比较。与NT管理相比，CT土壤倾向于具有更高的沙，更低的淤泥和更低的有机质。管理显着影响C五个土壤对中的四个的_bk值，其中粘土含量最高的三个在NT下的C _bk低于CT管理，而第四对在CT管理下的C _bk较低。长期的NT处理显示，在五对土壤中只有两对土壤盐分过程中因断裂而产生的垂直悬浮通量（ Gss _bk）显着低于CT处理。线性关系预测破损后的PM2.5排放占所测试的矿物土壤中PM10排放的一部分（R ²= 0.972）。这项研究有助于我们理解盐析过程中PM2.5和PM10的排放。它还提供了可改善风蚀预报系统（WEPS）模型中细粉尘模拟的参数。