农业工程学报
農業工程學報
농업공정학보
2014年
21期
278-285
,共8页
王仁德%肖登攀%常春平%郭中领
王仁德%肖登攀%常春平%郭中領
왕인덕%초등반%상춘평%곽중령
土壤%侵蚀%估算%风蚀事件%粒度对比法%河北坝上
土壤%侵蝕%估算%風蝕事件%粒度對比法%河北壩上
토양%침식%고산%풍식사건%립도대비법%하북패상
soil%erosion%estimation%wind erosion event%particle-size distribution comparison method%Bashang of Hebei Province
为了定量估算单次大风蚀事件的土壤风蚀量,该研究采用改进的粒度对比法对2014年春季一次大风蚀事件的农田风蚀量进行了估算。结果表明,在这次风蚀事件中,研究区农田风蚀量在0.35×106~4.11×106 kg/km2之间,平均为1.30×106 kg/km2,平均风蚀厚度0.9 mm。各采样点的风蚀量存在较大差距,翻耕耙平地的风蚀量显著大于莜麦留茬地,是莜麦留茬地风蚀量的2.85倍。这次风蚀事件使研究区2014年农田风蚀量增加了1倍,可见大风蚀事件对农田风蚀量的影响较大,一次风蚀事件产生的风蚀量可能超过多次小风蚀事件的总和。改进后的粒度对比法具有多方面的优势,取样厚度稍有变化,不可风蚀颗粒物的粒径取值范围稍有变化,都不会对公式计算结果造成显著影响。该方法方便快捷,操作简单,适用于地面平坦、不可风蚀物含量较高的农田上大风蚀事件风蚀量的估算。该研究在区域农田土壤风蚀评价和风蚀模型验证方面具有较好的应用前景。
為瞭定量估算單次大風蝕事件的土壤風蝕量,該研究採用改進的粒度對比法對2014年春季一次大風蝕事件的農田風蝕量進行瞭估算。結果錶明,在這次風蝕事件中,研究區農田風蝕量在0.35×106~4.11×106 kg/km2之間,平均為1.30×106 kg/km2,平均風蝕厚度0.9 mm。各採樣點的風蝕量存在較大差距,翻耕耙平地的風蝕量顯著大于莜麥留茬地,是莜麥留茬地風蝕量的2.85倍。這次風蝕事件使研究區2014年農田風蝕量增加瞭1倍,可見大風蝕事件對農田風蝕量的影響較大,一次風蝕事件產生的風蝕量可能超過多次小風蝕事件的總和。改進後的粒度對比法具有多方麵的優勢,取樣厚度稍有變化,不可風蝕顆粒物的粒徑取值範圍稍有變化,都不會對公式計算結果造成顯著影響。該方法方便快捷,操作簡單,適用于地麵平坦、不可風蝕物含量較高的農田上大風蝕事件風蝕量的估算。該研究在區域農田土壤風蝕評價和風蝕模型驗證方麵具有較好的應用前景。
위료정량고산단차대풍식사건적토양풍식량,해연구채용개진적립도대비법대2014년춘계일차대풍식사건적농전풍식량진행료고산。결과표명,재저차풍식사건중,연구구농전풍식량재0.35×106~4.11×106 kg/km2지간,평균위1.30×106 kg/km2,평균풍식후도0.9 mm。각채양점적풍식량존재교대차거,번경파평지적풍식량현저대우조맥류치지,시조맥류치지풍식량적2.85배。저차풍식사건사연구구2014년농전풍식량증가료1배,가견대풍식사건대농전풍식량적영향교대,일차풍식사건산생적풍식량가능초과다차소풍식사건적총화。개진후적립도대비법구유다방면적우세,취양후도초유변화,불가풍식과립물적립경취치범위초유변화,도불회대공식계산결과조성현저영향。해방법방편쾌첩,조작간단,괄용우지면평탄、불가풍식물함량교고적농전상대풍식사건풍식량적고산。해연구재구역농전토양풍식평개화풍식모형험증방면구유교호적응용전경。
Estimations were performed using improved particle-size distribution comparison method for the severe wind-erosion event in 2014 for the principal farmland types in the Bashang area of Hebei Province. The results showed that the soil loss of farmland by wind erosion in the severe wind-erosion event was 0.35×106-4.11×106 kg/km2, average wind erosion was 1.30×106 kg/km2, and the average depth of wind erosion was 0.09 cm. In the two farmland types, the soil loss by wind erosion of ploughed and raked fields during this event was 0.85×106-4.11×106 kg/km2 with an average of 2.00×106 kg/km2, and the soil loss by wind erosion of fields of oat stubble was 0.35×106-1.50×106 kg/km2 with an average of 0.70×106 kg/km2. The soil loss by wind erosion on fields of oat stubble was clearly less than on ploughed and raked fields (i.e., only 35.11%). Therefore, the presence of stubble can be seen as an effective measure against the erosion of farmland by wind. The soil loss by wind erosion at the different sampling sites varies considerably in this wind-erosion event. In the ploughed and raked fields, the soil loss by wind erosion at sampling site 1 was the largest (4.11×106 kg/km2), followed by sampling site 2 (1.66×106 kg/km2). Sampling site 3 shows the minimum soil loss by wind erosion (0.85×106 kg/km2), which was only 20.76% of that at sampling site 1. In the fields of oat stubble, the soil loss by wind erosion at sampling site 1 was the largest (1.50×106 kg/km2), followed by sampling point 4 (0.54×106 kg/km2). The soil loss by wind erosion at sampling point 2 was the minimum (0.35×106 kg/km2), which was equal to 23.12%of that at sampling site 1. <br> The severe wind erosion event greatly increased the soil loss of farmland by wind erosion in the study area, and the intensity of the wind erosion increased from moderate before the event to severe following it. The average soil loss of the various land types by wind erosion increased from 1.30×106 kg/km2 before the wind erosion event to 2.60×106 kg/km2 after it, i.e. it effectively doubled. The soil loss of ploughed and raked fields by wind erosion increased from 1.77×106 kg/km2 before the event to 3.67×106 kg/km2 after it (an increase of 1.07 times), and the soil loss of fields of oat stubble by wind erosion increased from 0.83×106 kg/km2 before the event to 1.53×106 kg/km2 after it (an increase of 0.85 times). Therefore, it is established that large wind-erosion events contribute significantly to the wind erosion of farmland and that the soil loss by wind erosion that occur in a severe wind-erosion event might be as great as the cumulative amount of erosion by several previous smaller wind erosion events. Generally, estimations of the soil loss of farmland by wind erosion, based on the improved particle-size distribution comparison method, matched the results obtained by other methods used in earlier research, as well as the results we obtained by field observations and wind-tunnel simulation. <br> The improved particle-size distribution comparison method has a number of advantages. Under the premise that the sampling thickness is larger than the thickness of the wind erosion layer, slight changes in the former would not obviously affect the results calculated by this method. Furthermore, under the premise that the value of non-erodible particles is larger than the threshold value of practical erodible and non-erodible particles, slight changes in the diameter value range of non-erodible particles would also not obviously affect the calculated results. In addition, this method is also convenient, rapid, simple to use, making it suitable for estimating the soil loss by wind erosion of flat farmland with a high content of non-erodible particles, under conditions of intense wind erosion.