LTREB: Ecosystem Structure and Function in Palouse Grasslands - Nitrogen, Plants, Grasshoppers and Birds

【摘要】LTREB: Palouse草原的生态系统结构和功能——氮、植物、蚱蜢和鸟类[ei: Belovsky， GaryInstitution: University of Notre dame]该LTREB项目对蒙大拿州四个栖息地的蚱蜢种群进行了持续监测和操纵，时间分别为17年、15年、14年和10年。监测测量蚱蜢、捕食者和植物丰度，以及营养和植物产量。通过改变蚱蜢密度和对蚱蜢的捕食来评估对营养和植物生产的影响。蚱蜢是主要的食草动物，影响营养和植物生产。因为蚱蜢的数量在不同年份之间变化很大，蚱蜢的影响也不同。蚱蜢的食草性可以通过减少营养物质来影响栖息地，从而减少植物产量，或者通过增加营养物质来增加植物产量。这项研究的目的是了解蚱蜢和它们的捕食者如何影响营养和植物生产。像这样的长期数据库对于评估生态系统结构（物种丰度）如何影响生态系统功能（营养和生产）至关重要。这是生态学中的一个核心问题，有几个应用。首先，蚱蜢被广泛认为是必须控制的害虫。这项研究评估了什么时候控制可能是有益的，甚至是有害的。其次，该研究有助于了解人类对生态系统的保护和恢复的影响。最后，通过让高中生、本科生和研究生，尤其是印第安人参与进来，教育效益也会增加。

ABSTRACTTitle: LTREB: Ecosystem structure and function in Palouse grasslands - nitrogen, plants, grasshoppers and birdsPI: Belovsky, GaryInstitution: University of Notre DameThis LTREB project continues monitoring and manipulations of grasshopper populations that have been conducted in four habitats in Montana for 17, 15, 14 and 10 years, respectively. The monitoring measures grasshopper, predator, and plant abundances, along with nutrients and plant production. The manipulations vary grasshopper density and predation on grasshoppers to assess impacts on nutrients and plant production. Grasshoppers are dominant herbivores and influence nutrients and plant production. Because grasshopper abundance varies dramatically between years, grasshopper influence also varies. Grasshopper herbivory can influence a habitat by either diminishing nutrients, which decreases plant production, or by increasing nutrients, which increases plant production. The purpose of this study is to understand how grasshoppers and their predators affect nutrients and plant production. Long term databases like this study are critical for assessing how ecosystem structure (species abundances) influence ecosystem function (nutrients and production). This is a central question in ecology with several applications. First, grasshoppers are widely considered to be pests that must be controlled. This study assesses when control may be beneficial or even detrimental. Second, the study helps to understand the human impacts on ecosystems for conservation and restoration. Finally, educational benefits accrue by involving high school, undergraduate and graduate students, especially Native Americans.