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在加拿大西部草原的半干旱区，种子直接播入谷物立茬十分普遍。４年的研究安排于萨斯喀彻温省的ＳｗｉｆｔＣｕｒｅｎｔ，以确定如何在高茬（＞３０ｃｍ）、低茬（约１５ｃｍ）和耕作茬下播种对硬红粒春小麦生长发育微气候的影响。各处理小区在整个冬季都为高留茬，播前即实施不同处理。与播入耕作茬的小麦相比，播入高茬的小麦籽粒产量和水分利用效率提高１２％左右，播入低茬的小麦产量和水分利用效率处于中间水平。此外，播入高茬的小麦较耕作茬高，干物质和叶面积较多，叶干物质比例较低，茎秆干物质比例高，收获指数较低。小麦生长期蒸散量（ＥＴ）不受残茬高度的影响。与耕作茬相比，在幼苗期高留茬可通过降低日均风速、土温和光辐射和增强光的反射而改变近地面的微气候。大部分生长季节中，测定表土的潜在ＥＴ量以高留茬明显最低，而小麦植株的蒸散比例较高，由于光合面积增加使净干物质积累效率增加。
In the semi-arid regions of western Canada’s grasslands, planting seeds directly into the seeds is quite common. The 4-year study was arranged in SwiftCurent, Saskatchewan to determine how the effects of sowing high-stubble (> 30 cm), low stubble (about 15 cm) and cropping on the growth and development of hard-core spring wheat microclimates. The treatment plot throughout the winter are high stubble, sowing before the implementation of different treatment. Compared with the wheat planted with tillable crop, grain yield and water use efficiency of wheat planted into high-stubble crop increased by about 12%. The yield and water use efficiency of wheat planted into low-stubble crop were at the middle level. In addition, wheat with high stubble was higher than tillage with higher dry matter and leaf area, lower proportion of leaf dry matter, higher percentage of stem dry matter and lower harvest index. Wheat evapotranspiration (ET) is not affected by stubble height. Compared with tillage stubble, stubble in seedling stage can change the sub-surface microclimate by reducing daily average wind speed, soil temperature and light radiation and enhancing light reflection. In most growing seasons, the potential evapotranspiration of topsoil was significantly lower with high stubble, while the proportion of wheat with higher evapotranspiration was higher. The net dry matter accumulation efficiency increased with the increase of photosynthetic area.