土壤有机碳代理指标
基于裸土合成影像的相对有机质指数，专为指导取样点布设而建。
每个像元合成到其最裸露的时刻，再按有机质排序。不报告碳含量。
Cropland at scale. The proxy tracks the darkening that follows organic matter.
它能发现什么
它检测什么。
| 材料 | 典型产出环境 | 可能的混淆因素 |
|---|---|---|
| Topsoil organic matter, relative index | Cropland, grassland and rangeland topsoil, the top few centimetres only | Surface moisture darkens soil the same way organic matter does; roughness and shadow do too |
方法
工作原理。
输入校准反射率，每个像元都对照公开参考库进行拟合。
Bare-soil compositing
A multi-year series is filtered down to the moments when each pixel was most exposed, and those moments are composited. Cloud-free compositing over a date range is a shipping capability.
Moisture and roughness caution
Wet soil is darker than dry soil of the same composition, and rough soil is darker than smooth. Both effects sit on top of the one being measured, and neither is fully removed by the soil line correction applied here.
Regression onto laboratory libraries (not built)
Turning reflectance into a carbon figure means fitting against a laboratory soil library and validating that fit region by region. That work is on the roadmap, and until it lands the output stays a relative index.
Relative index output
What ships is a ranking within a field or a run of fields on the same composite, useful for deciding where to sample.
技术规格
您得到什么，它在什么数据上运行。
所需环境条件
Method and checks are documented in Axine Applied Spectroscopy Paper #5 · Section 4.2.
适用边界
A relative ranking that tells you where to sample. No carbon content is reported.
