Crop Generator R Code
| Main Author: | Conradt, Tobias |
|---|---|
| Format: | info software Journal |
| Terbitan: |
, 2021
|
| Subjects: | |
| Online Access: |
https://zenodo.org/record/4704561 |
Daftar Isi:
- In most agricultural systems around the globe different crops are grown on a field over time in order to control pests and maintain soil fertility. This is often realized by standardized repetitions of specific crops, also called rotations. The challenge addressed by this code is to implement such rotations in a spatially distributed model without explicit knowledge of the spatio-temporal crop distribution in the real landscape. In addition, the spatial sub-units of the model can be much coarser than the actual fields. However, it is required that the model rotations follow agricultural expertise (e.g. make sure that a certain number of years have passed until a certain crop is planted again in the same location) and that the crop shares integrated over a larger area (model domain, administrative region) remain more or less stable between years and resemble the known agricultural statistics of that area. The core problem is solved through quadratic programming – through the quadprog library of R: The overall crop shares of the agricultural statistics are met by crop sequences selected from a pre-defined database. The database is limited to allowed rotations considering agricultural practice rules (and ideally contains the rotations most frequently applied in reality). The program output contains also application probabilities for the selected model crop sequences which cumulate to one. With this information, model crop rotations can be suitably distributed in the agricultural or hydrological model. An example application for parts of Central Europe is described in an article currently under revision with Agricultural Systems: Sietz, D., T. Conradt, V. Krysanova, F. F. Hattermann & F. Wechsung (2021) The Crop Generator: Implementing crop rotations to effectively advance eco-hydrological modelling.