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Updated: May 22, 2025

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优化跨跨度基方法的采样,提高了农业生态监测数据的强度
Sarah E McCord1, Nicholas P Webb1, Justin W Van Zee1
1USDA-ARS Jornada Experimental Range, Las Cruces, New Mexico, USA.
Journal of environmental quality
|March 17, 2025
概括
为生态系统监测优化截面采样至关重要. 每块土地上有三条100米的横段,有效地减少了植物覆盖面和物种数量等关键生态指标的采样误差.
科学领域:
- 生态生态学 生态生态学
- 环境科学 环境科学
- 生态监测 生态监测
背景情况:
- 基于交叉点的监测,包括线点交叉点 (LPI),植被高度和树冠间隙交叉点,对于评估生态系统状况至关重要.
- 设计有效的采样策略以检测这些方法的生态变化仍然是研究人员面临的挑战.
研究的目的:
- 确定用于描述生态系统特征和使用基于核心跨度的方法检测变化的最低采样要求.
- 为了确定最佳的截面长度和数量,以便进行强大的生态监测和分析.
主要方法:
- 评估了LPI,植被高度和树冠间隙拦截方法对截断长度,数量和采样间隔的灵敏度.
- 利用了来自五个生物体的13个国家风侵蚀研究网络地点的数据,包括151个图片采样事件.
主要成果:
- 增加截面复制量和长度在减少采样误差方面更有效,而不是增加沿较少的截面采样强度.
- 每块地块的三条100米横段实现了顶间隙拦截和LPI叶覆盖的±5%误差,高度为±5厘米,LPI物种数量为±2种在95%的置信区间.
- 两个100米横断段在80%的置信区间内满足了相同的标准.
结论:
- 截面采样设计显著影响了现场规模的推断和对生态动态的理解.
- 建议在每块土地上使用三条100米的横段进行可靠的生态系统监测和在多种生物群中检测变化.
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