Data providers
pcse.input 模块包含所有用于读取天气文件的类，参数文件和农业管理文件。
classpcse.input.NASAPowerWeatherDataProvider(latitude, longitude, force_update=False, ETmodel='PM')[source]
用于使用 NASA POWER 数据库配合 PCSE 的 WeatherDataProvider
Parameters:
latitude -- latitude to request weather data for
longitude -- longitude to request weather data for
force_update -- Set to True to force to request fresh data from POWER website.
ETmodel -- "PM"|" P" for selecting penman-monteith or Penman method for reference evapotranspiration. Defaults to "PM".
ETmodel 参数： "PM" = Penman-Monteith；"P" = Penman（1948）
二者都是"参考作物蒸散量（ET₀）"的经典算法，但精度、数据需求、适用范围不同，一句话区别：
Penman-Monteith 是世界粮农组织 FAO-56 推荐的唯一标准方法；
Penman（1948）是老版本、简化版，现在基本被 PM 取代。
WOFOST 作物模拟流程
classpcse.crop.phenology.DVS_Phenology(**kwargs)
WOFOST 用无量纲尺度来描述物候进程：
出苗 = 0；开花（Anthesis）= 1；成熟 = 2
这种"0-1-2"框架主要面向谷类作物。
其他作物被强行套用这个标尺，虽然对某些作物并不完全合适。
例如：马铃薯在第 1 阶段并不代表开花，而是块茎开始形成。
物候发育主要由温度驱动：
开花前：温度为主，还可被日长和春化作用修正。
开花后：仅受温度影响，发育速率不再受日长和春化调节。
调用不同模型模拟区别
| Model | Production level | CO₂ impact | Biomass reallocation | N dynamics | Water balance | N balance |
|---|---|---|---|---|---|---|
| Wofost72_Pheno | Phenology only | --- | --- | --- | --- | --- |
| Wofost72_PP | Potential | --- | --- | --- | --- | --- |
| Wofost72_WLP_CWB | Water-limited | --- | --- | --- | Classic | --- |
| Wofost73_PP | Potential | ✓ | ✓ | --- | --- | --- |
| Wofost73_WLP_CWB | Water-limited | ✓ | ✓ | --- | Classic | --- |
| Wofost73_WLP_MLWB | Water-limited | ✓ | ✓ | --- | Multi-layer | --- |
| Wofost81_PP | Potential | ✓ | ✓ | ✓ | --- | --- |
| Wofost81_WLP_CWB | Water-limited | ✓ | ✓ | ✓ | Classic | --- |
| Wofost81_WLP_MLWB | Water-limited | ✓ | ✓ | ✓ | Multi-layer | --- |
| Wofost81_NWLP_CWB_CNB | Water & N limited | ✓ | ✓ | ✓ | Classic | Classic |
| Wofost81_NWLP_MLWB_CNB | Water & N limited | ✓ | ✓ | ✓ | Multi-layer | Classic |
| Wofost81_NWLP_MLWB_SNOMIN | Water & N limited | ✓ | ✓ | ✓ | Multi-layer | SNOMIN |
| Lingra10_PP | Potential | ✓ | --- | --- | --- | --- |
| Lingra10_WLP_CWB | Water-limited | ✓ | --- | --- | Classic | --- |
| Lingra10_NWLP_CWB_CNB | Water & N limited | ✓ | ✓ | ✓ | Classic | Classic |
| Lintul10_NWLP_CWB_CNB | Water & N limited | ✓ | --- | ✓ | Classic | Classic |
| Alcepas10_PP | Potential | --- | --- | --- | --- | --- |
| FAO_WRSI10_WLP_CWB | Water-limited | --- | --- | --- | Classic | --- |