Ecological effects of prescribed fire on a sagebrush-steppe rangeland

Rangelands encompass approximately 26% of land in the United States with the federal government managing 62 million hectares (Lubowski et al. 2006). A key component of rangeland sites for feeding wildlife is the insect community. Land management, particularly prescribed fire, may reduce plant species diversity, thus reducing both pollinator habitat and the quantity of other invertebrates used as food resources (Beck et al. 2008). Fire can also change the amount of surface wood, thereby altering soil properties and ground-dwelling insects. Prescribed fire creates temporal changes to rangeland hydrology, commonly increasing runoff and erosion (Meeuwig 1971; DeBano 1981; Pierson et al. 2001, 2002, 2008; Williams et al. 2016). Post-fire erosion and runoff increases can be attributed to changes in soil cover (Pierson et al. 2001, 2008; Williams et al. 2016), altered organic matter content (DeBano et al. 1998), vegetation (Williams et al. 2016) and increased runoff leading to increased sediment transport capacity (Pierson et al. 2009; Williams et al. 2016). This data publication contains data from a study trying to quantify prescribed fire impacts on surface and belowground changes at a sagebrush site near Red Mountain, which is on the Caribou-Targhee National Forest, approximately 43 kilometers (17 miles) northeast of Montpelier, Idaho. This site received a prescribed burn in 2003. Shortly after the burn, four treated plots were installed. Snow prevented the installation of three control plots until the following year, 2004. A weather station was installed on the study site near the south side of a ridgeline. Precipitation, temperature, humidity, solar radiation, as well as wind speed and direction were recorded continuously from October 16, 2003, through August 27, 2010. After the spring of 2007, the precipitation gauge stopped functioning. Data collected between 2003 and 2010 include bulk density, ground cover, soil loss, weather, and hillslope runoff plot measurements. Particle size analysis was performed on all bulk density samples and 2003-2005 soil samples.The purpose of this study was to quantify prescribed fire impacts on surface (erosion, runoff, sediment production, soil cover recovery, and ground dwelling insects) and belowground changes (soil chemical and physical properties, incidence of termites, and changes in decomposition rate) in a sagebrush site that had recently received a prescribed burn. Specifically, we hypothesized that prescribed burning would increase belowground decomposition rates, insect diversity and numbers, and surface runoff and erosion. We also hypothesized that at the end of 5 years these changes would return to pre-burn levels.

草原地区约占美国陆地面积的26%，其中62百万公顷由联邦政府管理（Lubowski等，2006年）。草原生态系统中，为野生动物提供食物的关键组成部分是昆虫群落。土地利用管理，尤其是预定焚烧，可能降低植物物种多样性，从而减少传粉者栖息地以及其他作为食物资源的无脊椎动物的存量（Beck等，2008年）。火势亦能改变地表木质物的数量，进而影响土壤特性和地表栖息的昆虫。预定焚烧会对草原水文产生时间性变化，通常会增加径流和侵蚀（Meeuwig，1971年；DeBano，1981年；Pierson等，2001年、2002年、2008年；Williams等，2016年）。火灾后侵蚀和径流的增加可归因于土壤覆盖的变化（Pierson等，2001年、2008年；Williams等，2016年）、有机物质含量的改变（DeBano等，1998年）、植被（Williams等，2016年）以及径流增加导致的泥沙运输能力提升（Pierson等，2009年；Williams等，2016年）。本数据集收录了一项旨在量化预定焚烧对位于红山附近，Caribou-Targhee国家森林内，约43公里（17英里）东北方向的灌木丛生态位地表及地下变化影响的研究数据。该地点于2003年接受了预定焚烧。焚烧后不久，安装了四个处理区。由于降雪，三个对照区直至次年，即2004年才得以安装。研究地点南坡附近安装了气象站，从2003年10月16日至2010年8月27日，持续记录了降水量、温度、湿度、太阳辐射以及风速和风向。2007年春季后，降水量计停止工作。2003年至2010年间收集的数据包括土壤密度、地表覆盖、土壤流失、气象以及山坡径流测量。对所有的土壤密度样本和2003-2005年的土壤样本进行了颗粒大小分析。本研究的目的是量化预定焚烧对近期接受预定焚烧的灌木丛生态位地表（侵蚀、径流、泥沙产生、土壤覆盖恢复和地表栖息的昆虫）及地下变化（土壤化学和物理性质、白蚁发生率以及分解速率的变化）的影响。具体而言，我们提出了预定焚烧会增加地下分解速率、昆虫多样性和数量、地表径流和侵蚀的假设。我们还假设，在5年结束时，这些变化将恢复至焚烧前的水平。