SGER: Unusual Biologic Activity on Desert Pavement Surfaces in Response to Recent El Nino Event, Mojave Desert, California

在莫哈韦沙漠地区，人们在几十年的时间里观察到基本上没有一年生植物生长的HaffDesert人行道表面，今年春天却被一年生植物的密集生长所侵入。 据推断，这种不寻常的增加路面生物量是由于异常潮湿的天气与最近的厄尔尼诺事件。 本建议书要求支持立即对受影响的路面进行实地考察，以便在植被随季节性温度升高而消失之前记录植被模式和密度，并评估可能直接或间接（通过觅食动物）对稳定路面造成的任何变化。 计划在今年秋天进行一次后续实地考察。 这项实地研究的结果将被用来确定是否在其他稳定的沙漠路面表面的表面碎屑图案包含有关过去的环境变量，如当地降水量的变化信息。

9814276HaffDesert pavement surfaces in the Mojave Desert region that were observed over a period of several decades to have been essentially free of annual plant growth were observed this spring to have been invaded by dense growths of annual vegetation. It is inferred that this unusual increase in pavement biomass was due to the abnormally wet weather associated with the recent El Nino event. This proposal requests support for an immediate field visit to affected pavement sites to document vegetation patterns and densities before the vegetation fades with increasing seasonal temperatures, and to assess any changes that may have been caused either directly or indirectly (via foraging animals) to the otherwise stable pavement surfaces. A follow up field trip is planned for this coming fall. The results of this field study will be used to determine whether surface clast patterns on otherwise stable desert pavement surfaces contain information about past variations of environmental variables such as local precipitation.