Cooley Savannah S, Pinto Naiara, Becerra Milagros, Alvarado Jorge Washington Vela, Fahlen Jocelyn C, Rivera Ovidio, Fricker G Andrew, Dantas Augusto Rafael De Los Ríos, Aguilar-Amuchastegui Naikoa, Reygadas Yunuen, Gan Julie, DeFries Ruth, Menge Duncan N L
NASA Jet Propulsion Laboratory California Institute of Technology Pasadena California USA.
Department of Ecology, Evolution, and Environmental Biology Columbia University New York New York USA.
Ecol Evol. 2024 Aug 6;14(8):e70116. doi: 10.1002/ece3.70116. eCollection 2024 Aug.
Improving our ability to monitor fragmented tropical ecosystems is a critical step in supporting the stewardship of these complex landscapes. We investigated the structural characteristics of vegetation classes in Ucayali, Peru, employing a co-production approach. The vegetation classes included three agricultural classes (mature oil palm, monocrop cacao, and agroforestry cacao plantations) and three forest regeneration classes (mature lowland forest, secondary lowland forest, and young lowland vegetation regrowth). We combined local knowledge with spaceborne lidar from NASA's Global Ecosystem Dynamics Investigation mission to classify vegetation and characterize the horizontal and vertical structure of each vegetation class. Mature lowland forest had consistently higher mean canopy height and lower canopy height variance than secondary lowland forest (μ = 29.40 m, sd = 6.89 m vs. μ = 20.82 m, sd = 9.15 m, respectively). The lower variance of mature forest could be attributed to the range of forest development ages in the secondary forest patches. However, secondary forests exhibited a similar vertical profile to mature forests, with each cumulative energy percentile increasing at similar rates. We also observed similar mean and standard deviations in relative height ratios (RH50/RH95) for mature forest, secondary forest, and oil palm even when removing the negative values from the relative height ratios and interpolating from above-ground returns only (mean RH50/RH95 of 0.58, 0.54, and 0.53 for mature forest, secondary forest, and oil palm, respectively) ( < .0001). This pattern differed from our original expectations based on local knowledge and existing tropical forest succession studies, pointing to opportunities for future work. Our findings suggest that lidar-based relative height metrics can complement local information and other remote sensing approaches that rely on optical imagery, which are limited by extensive cloud cover in the tropics. We show that characterizing ecosystem structure with a co-production approach can support addressing both the technical and social challenges of monitoring and managing fragmented tropical landscapes.
提高我们监测破碎化热带生态系统的能力是支持对这些复杂景观进行管理的关键一步。我们采用共同生产方法，调查了秘鲁乌卡亚利植被类别的结构特征。植被类别包括三种农业类别（成熟油棕、单作可可和农林复合可可种植园）和三种森林再生类别（成熟低地森林、次生低地森林和年轻低地植被再生）。我们将当地知识与美国国家航空航天局全球生态系统动力学调查任务的星载激光雷达相结合，对植被进行分类，并描述每个植被类别的水平和垂直结构。成熟低地森林的平均树冠高度始终高于次生低地森林，树冠高度方差低于次生低地森林（分别为μ = 29.40米，标准差 = 6.89米，对比μ = 20.82米，标准差 = 9.15米）。成熟森林方差较低可能归因于次生林斑块中森林发育年龄的范围。然而，次生林与成熟林呈现出相似的垂直剖面，每个累积能量百分位数以相似的速率增加。即使从相对高度比中去除负值并仅根据地面以上回波进行插值，我们在成熟森林、次生森林和油棕的相对高度比（RH50/RH95）中也观察到了相似的均值和标准差（成熟森林、次生森林和油棕的平均RH50/RH95分别为0.58、0.54和0.53）（< 0.0001）。这种模式与我们基于当地知识和现有热带森林演替研究的最初预期不同，指出了未来工作的机会。我们的研究结果表明，基于激光雷达的相对高度指标可以补充当地信息以及其他依赖光学图像的遥感方法，而光学图像在热带地区受广泛云层覆盖的限制。我们表明，采用共同生产方法来描述生态系统结构有助于应对监测和管理破碎化热带景观的技术和社会挑战。
