Summer droughts in North America's northern Great Plains are expected to increase in frequency and duration as precipitation shifts toward spring and fall. Two rangeland experimental stations in North Dakota experienced drought in 2017 relative to 25-year averages. The southwest location had a 170-mm deficit from the 360-mm normal rainfall and was grazed by cattle (Bos taurus L.) and sheep (Ovis aries L.); the south-central location had 109 mm below the 403-mm normal rainfall and was grazed by cattle. We evaluated patch-burn grazing as a drought resilient land management strategy in the northern Great Plains by comparing average daily gains, fecal density, available forage biomass, and forage crude protein content. At the southwest location, livestock performed better during the drought season compared with animals on the same pastures in the previous year, which had near-normal rainfall but no fire. At the central location, cows on patch-burned pastures performed better than cows on continuously-grazed, unburned pastures in the same year under drought conditions; all cows were nursing calves and calf gains did not vary between treatments. In both locations, the burned patches had higher fecal density and lower available forage biomass than patches not yet burned throughout the grazing season, indicating grazer attraction to burned areas. Despite drought, burned patches maintained grazer attraction and animal performance was maintained or even improved, which contrasts with the expected relationship between animal performance and precipitation. This study indicated that prescribed patch-burning might mitigate drought by buffering forage resources (crude protein content and availability) and maintaining animal performance (average daily gains).

随着降水向春季和秋季转移，预计北美北部大平原的夏季干旱的频率和持续时间将增加。与25年平均值相比，北达科他州的两个牧场实验站在2017年经历了干旱。西南位置比正常降雨360毫米的降雨量少了170毫米，并以牛（Bos taurus L.）和绵羊（Ovis aries）为食L.）; 中南部位置比403毫米正常降雨量少109毫米，并被牛放牧。通过比较平均日增重，粪便密度，可用牧草生物量和牧草粗蛋白含量，我们评估了大平原北部斑块放牧作为一种抗旱土地管理策略。在西南地区，与上一年相同牧场的动物相比，干旱季节的牲畜表现更好，后者的降雨量接近正常，但没有着火。在中心位置，同一年在干旱条件下，贴片烧制牧场上的母牛表现优于连续放牧，未烧制牧场上的母牛。所有的母牛都是犊牛，两次处理之间的犊牛增重没有变化。在两个地方 与整个放牧季节尚未燃烧的斑块相比，燃烧的斑块具有较高的粪便密度和较低的可用牧草生物量，表明放牧者对燃烧的区域有吸引作用。尽管干旱，烧过的斑块仍保持了放牧者的吸引力，并且动物的性能得以保持甚至提高，这与动物的性能和降水之间的预期关系形成了鲜明的对比。这项研究表明，规定的斑块燃烧可以通过缓冲饲料资源（粗蛋白质含量和可用性）并保持动物生长性能（平均日增重）来减轻干旱。这与动物性能和降水之间的预期关系形成对比。这项研究表明，规定的斑块燃烧可以通过缓冲饲料资源（粗蛋白质含量和可用性）并保持动物生长性能（平均日增重）来减轻干旱。这与动物性能和降水之间的预期关系形成对比。这项研究表明，规定的斑块燃烧可以通过缓冲饲料资源（粗蛋白质含量和可用性）并保持动物生长性能（平均日增重）来减轻干旱。