Remote Sensing Algorithms for Mapping Regenerative Agriculture
This invention relates to methods for determining adoption and impact of regenerative farming practices. Embodiments of these methods, take satellite imagery and weather data as inputs, process those data according to methods of the present invention, and produce outputs which indicate whether a specific farming practice (for example, no-till or cover cropping) was adopted for a particular field or region for a particular season.
1 . A method of predicting a tillage practice, the method comprising:
receiving a time series of satellite imagery, the time series of satellite imagery covering at least a geographic region, during a predetermined time period; generating a first set of field level zonal summary time series from the time series of satellite imagery for at least one field within the geographic region, wherein the field level zonal summary time series comprises at least a normalized difference tillage index (NDTI) time series and a normalized difference vegetation index (NDVI) time series;
for each field in the geographic region, determining a dormant period during the predetermined time period, wherein the dormant period is comprised of at least two consecutive observations of NDVI values<0.3;
for each observation in each dormant period in the first set of field level zonal summary time series identifying a soil moisture percentage and removing from further analysis dormant periods wherein the average soil moisture percentage during the dormant period exceeds a threshold value;
for each dormant period, determining the difference between minimum NDTI value of all observations during the dormant period and the 90th percentile of NDTI values from historical data; and
for each field in the geographic region, apply a decision tree classifier to a field wherein a field is predicted to be tilled if minimum NDTI is <0.05 or the difference between minimum NDTI or the 90th percentile of NDTI is >0.09.
2 . The method of claim 1 , wherein the geographic region is one or more states, counties, farms, or fields.
3 . The method of claim 1 , wherein observations of the field level zonal summary time series are removed from analysis if the NDTI value of the subsequent observation increases by >0.05 between observations and <5 mm of rain was recorded between observations.
4 . The method of claim 1 , wherein the predetermined time period begins with the end of a first crop season and ends with the end of the following crop season.
5 . The method of claim 1 , wherein more than one dormant region is detected for a field in the geographic region and the dormant period having the lowest NDTI value is used.
6 . The method of claim 1 , wherein the threshold value is 40% soil moisture.
7 . A non-transitory computer-readable medium comprising memory with instructions encoded thereon for predicting a tillage practice, the instructions when executed causing one or more processors to perform operations comprising:
receiving a time series of satellite imagery, the time series of satellite imagery covering at least a geographic region, during a predetermined time period; generating a first set of field level zonal summary time series from the time series of satellite imagery for at least one field within the geographic region, wherein the field level zonal summary time series comprises at least a normalized difference tillage index (NDTI) time series and a normalized difference vegetation index (NDVI) time series;
for each field in the geographic region, determining a dormant period during the predetermined time period, wherein the dormant period is comprised of at least two consecutive observations of NDVI values<0.3;
for each observation in each dormant period in the first set of field level zonal summary time series identifying a soil moisture percentage and removing from further analysis dormant periods wherein the average soil moisture percentage during the dormant period exceeds a threshold value;
for each dormant period, determining the difference between minimum NDTI value of all observations during the dormant period and the 90th percentile of NDTI values from historical data; and
for each field in the geographic region, apply a decision tree classifier to a field wherein a field is predicted to be tilled if minimum NDTI is <0.05 or the difference between minimum NDTI or the 90th percentile of NDTI is >0.09.
8 . The non-transitory computer-readable medium of claim 7 , wherein the geographic region is one or more states, counties, farms, or fields.
9 . The non-transitory computer-readable medium of claim 7 , wherein observations of the field level zonal summary time series are removed from analysis if the NDTI value of the subsequent observation increases by >0.05 between observations and <5 mm of rain was recorded between observations.
10 . The non-transitory computer-readable medium of claim 7 , wherein the predetermined time period begins with the end of a first crop season and ends with the end of the following crop season.
11 . The non-transitory computer-readable medium of claim 7 , wherein more than one dormant region is detected for a field in the geographic region and the dormant period having the lowest NDTI value is used.
12 . The non-transitory computer-readable medium of claim 7 , wherein the threshold value is 40% soil moisture.
13 . A method of detecting a tillage event, the method comprising:
based on a time-series of satellite imagery, identifying one or more dormancy period of a cultivated area, wherein
identifying the one or more dormancy period comprises determining a period in which a vegetation index of the cultivated is below a threshold;
within the one or more dormancy period, determining a residue cover index of the cultivated area; and
providing the residue cover index to a trained classifier, and receiving therefrom an indication of the presence or absence of a tillage event.
14 . The method of claim 13 , wherein the vegetation index and/or the residue cover index is NDVI.
15 . The method of claim 13 , wherein the threshold is 0.3.
16 . The method of claim 13 , wherein the threshold is predetermined according to historical data.
17 . The method of claim 13 , wherein the residue cover index is a minimum value of NDTI within the one or more dormancy period.
18 . The method of claim 13 , further comprising:
providing one or more of: a vegetation index, an indication of soil moisture, or a drop in residue cover index to the trained classifier.
19 . The method of claim 13 , wherein the classifier is a decision tree.