Package 'cropZoning'

Climate crop zoning based on monthly air temperature data

Description

This function will calculate the climate crop zoning for the range of air temperature informed. The result will be a raster image with five possible values (values of 1 to 5) according to what is explained below.

• Pixel values = 1, correspond to suitable air temperature (ST);

• Pixel values = 2, correspond to restricted due to low temperature (RLT);

• Pixel values = 3, correspond to restricted due to high temperature (RHT);

• Pixel values = 4, correspond to unsuitable due to low temperature (ULT);

• Pixel values = 5, correspond to unsuitable due to high temperature (UHT).

The thermal suitability ranges established were as follows:

1. ST - Temperature range (range of temp2 to temp3) considered optimal for the growth, development and production of the crop;

2. RLT - Temperature range (range of temp2 to temp1) which the crop is able to develop, however, below its potential due to the air temperature values being slightly lower than those of the suitable range;

3. RHT - Temperature range (range of temp3 to temp4) which the crop is able to develop, however, below its potential due to the temperature values being slightly higher than those of the suitable range;

4. ULT - When temperature values are not suitable for commercial exploitation of the crop due to low air temperature (air temperature below the temp1);

5. UHT - When temperature values are not suitable for commercial exploitation of the crop due to high air temperature (air temperature above the temp4);

Usage

ccrop_zoning(temp_per_month, temp1, temp2, temp3, temp4)

Arguments

temp_per_month	Rasterstack object with a monthly mean air temperature from a period of time
temp1	unsuitable due to low temperature (numeric)
temp2	minimum suitable temperature (numeric)
temp3	maximum suitable temperature (numeric)
temp4	unsuitable due to high temperature (numeric)

Value

Returns a SpatRaster object of climate crop zoning based in air temperature.

Examples

## Not run: 
### Example with Brazil states

see_brazil_states()

image_tmin<-loadROI(variable = "tmin", 
                   region = "brazil", 
                   sub_region = 13) # sub_regions 1:27
                   
image_tmax<-loadROI(variable = "tmax",
                   region = "brazil", 
                   sub_region = 13)
                   
image_tmean <- tmean(tmax_stack = image_tmax, tmin_stack = image_tmin)


start_date <- c('2000-01-01')
end_date <- c('2017-12-01')

tmean_monthly <- tmean_monthly_stack(tmean_stack = img_tmean,
                                    start_date = start_date,
                                    end_date = end_date)
                                    
                    
zoning <- ccrop_zoning(temp_per_month = tmean_monthly,
                       temp1 = 10 , temp2 = 20, 
                       temp3 = 30, temp4 = 40)

## End(Not run)

---

Download of maximum and minimum air temperature from 'TerraClimate'

Description

This function will download the tmax and tmin images and will load a rasterstack according to the the region of interest (Region and sub_region). The images downloaded by this function are intended to be used for calculating the climatic zoning of crops. To calculate the climatic zoning of the crops, you first have to calculate the mean air temperature (function tmean) and the monthly air temperature (function tmean_monthly).

Usage

download_terraclimate(dir_out, variable, years, region, sub_region)

Arguments

dir_out	Directory where you want to save the raster images that you are goind to download. Each variable should be locate in one folder.
variable	Variable to download. The variables can be the minimum (tmin) or maximum (tmax) air temperature of 'TerraClimate' (Rasterstack).
years	The period in years that the function should download.
region	Use the "brazil" shapefile to extract the Rasterstack (variable) for one state (Brazilian state), or use the "biomes_brazil" to extract the Rasterstack (variable) for one biome of Brazil.
sub_region	You have two options in this section, if you choice the brazil (in region parameter) you need to choice the Brazilian states, but if you choice the biomes_brazil (in region parameter) you must choice one of Brazilian biomes. Another option is to select "all" to download images for the entire territory of Brazil.

Value

Returns a Rasterstack of tmin (minimum air temperature) or tmax (maximum air temperature).

References

The images used in this package can be found in the paper: Abatzoglou, J.T., S.Z. Dobrowski, S.A. Parks, K.C. Hegewisch, 2018, Terraclimate, a high-resolution global dataset of monthly climate and climatic water balance from 1958-2015, Scientific Data.

Examples

## Not run: 

### Downloading the minimum air temperature and maximum air temperature based on Brazil states.
see_brazil_states()

img <- download_terraclimate(
  dir_out = "C:/teste/tmin/state", variable = "tmin",
  years = c(2018:2019),
  region = "brazil",
  sub_region = 13
)

### Downloading the minimum air temperature and maximum air temperature based on Brazil states.
see_brazil_biomes()

img <- download_terraclimate(
  dir_out = "C:/teste/tmin/biome", variable = "tmin",
  years = c(2018:2019),
  region = "biomes_brazil",
  sub_region = 6
)

## End(Not run)

---

Load the data for the region of interest (ROI)

Description

This function will load the air temperature data (SpatRaster) for the region of interest (ROI). The images loaded by this function are intended to be used, as example, for calculating the climatic zoning of crops. To calculate the climatic zoning of the crops, you first have to calculate the mean air temperature (function tmean) and the monthly air temperature (function tmean_monthly).

Usage

loadROI(variable, region, sub_region)

Arguments

variable	Stack of minimum (tmin) or maximum (tmax) air temperature (SpatRaster).
region	Use the "brazil" shapefile to extract the SpatRaster (variable) for one state (Brazilian state), or use the "biomes_brazil" to extract the Rasterstack (variable) for one biome of Brazil.
sub_region	You have two options in this section, if you choice the brazil (in region parameter) you need to choice the Brazilian states, but if you choice the biomes_brazil (in region parameter) you must choice one of Brazilian biomes.

Value

Load the tmin image example (minimum air temperature) or tmax image example (maximum air temperature) rasterstack

References

The images used in this package can be found in the paper: Abatzoglou, J.T., S.Z. Dobrowski, S.A. Parks, K.C. Hegewisch, 2018, Terraclimate, a high-resolution global dataset of monthly climate and climatic water balance from 1958-2015, Scientific Data.

Examples

## Not run: 

### Loading minimum air temperature and maximum air temperature based on Brazil states.
see_brazil_states()

image_tmin <-loadROI(variable = "tmin", 
                   region = "brazil", 
                   sub_region = 13) # sub_regions 1:27
                    
image_tmax <-loadROI(variable = "tmax",
                   region = "brazil", 
                   sub_region = 13)

### Loading minimum air temperature and maximum air temperature based on Brazil biomes.
see_brazil_biomes()

image_tmin <- loadROI(variable = tmin, 
                    region = "biomes_brazil",
                    sub_region = 5)# sub regions: 1:6 (biomes)
                    
image_tmax <-loadROI(variable = "tmax",
                   region = "biomes_brazil", 
                   sub_region = 5)


## End(Not run)

---

Function to plot the climate crop zoning stack generated in ccrop_zoning

Description

This function will plot the ccrop_zoning output. The result of the plotting will generate a plot with the following classes.

Climatic zoning classes:

• ST: Suitable air temperature

• RLT: Restricted due to low temperature

• RHT: Restricted due to high temperature

• ULT: Unsuitable due to low temperature

• UHT: Unsuitable due to high temperature

Usage

plot_ccrop_zoning(zoning)

Arguments

zoning

A stack generated in ccrop_zoning

Value

Returns a plot (ggplot object) with the monthly climate crop zoning based in air temperature.

Examples

### Data preparation
## Not run: 
###ploting the cropzoning:

zoning_plot <- plot_ccrop_zoning(zoning)

## End(Not run)

---

Function to see the Brazilian biomes available in cropZoning package and how we can use it in the loadROI function

Description

This fuction will show the biomes available in the package and how we can call each biome polygon.

Usage

see_brazil_biomes()

Value

Returns a character strings listing the biomes available to run the cropZoning package.

Examples

## Not run: 

see_brazil_biomes()

## End(Not run)

---

Function to see the Brazilian states available in cropZoning package and how we can use it in the loadROI function

Description

This function will show the Brazilian state available in the package and how we can call each state polygon.

Usage

see_brazil_states()

Value

Returns a character strings listing the the Brazilian states available to run the cropZoning package.

Examples

## Not run: 

see_brazil_states()

## End(Not run)

---

Calibration of maximum air temperature from TerraClimate

Description

This function will calibrate the maximum air temperature from TerraClimate dataset based in the relationship with observed weather stations data.The values of slope and intercept informed in example correspond a calibration performed between 'Terraclimate' images and INMET automatic weather stations realized for all the brazilian territory.

Usage

tmax_calibration(slope, intercept, tmax_stack)

Arguments

slope	the slope of the linear regression (numeric)
intercept	the intercept of the linear regression (numeric)
tmax_stack	stack of maximum air temperature

Value

Returns a SpatRaster object of calibrated maximum air temperature.

Examples

## Not run: 

tmax_cal<- tmax_calibration(slope = 0.874787, intercept = 4.612894 , tmax_stack = tmax);

## End(Not run)

---

Mean air temperature calculation

Description

This fuction will calculate the mean air temperature from minimum and maximum air temperature data.

Usage

tmean(tmax_stack, tmin_stack)

Arguments

tmax_stack	stack of maximum air temperature
tmin_stack	stack of minimum air temperature

Value

Returns a SpatRaster object of mean air temperature.

Examples

## Not run: 

image_tmean <- tmean(tmax_stack = image_tmax, tmin_stack = image_tmin)

## End(Not run)

---

Monthly mean air temperature estimation to generate the climate crop zoning

Description

This function will calculate the mean monthly air temperature based on the period of time selected (start_date and end_date).

Usage

tmean_monthly_stack(tmean_stack, start_date, end_date)

Arguments

tmean_stack	Stack of mean air temperature based on minimum and maximum air temperature Rasterstack
start_date	Date that start the investigation, should be in the following format (1958-01-01 /Year-Month-Day)
end_date	Date that end the investigation, should be in the following format (2017-12-31 /Year-Month-Day)

Value

Returns a Rasterstack object with a monthly mean air temperature from a period of time.

Examples

## Not run: 

start_date <- c('2000-01-01')
end_date <- c('2017-12-01')

tmean_monthly <- tmean_monthly_stack(tmean_stack = img_tmean,
                                    start_date = start_date,
                                    end_date = end_date)

## End(Not run)

---

Calibration of minimum air temperature from TerraClimate

Description

This function will calibrate the minimum air temperature from TerraClimate dataset based in the relationship with observed weather stations data. The values of slope and intercept informed in example correspond a calibration performed between 'Terraclimate' images and INMET automatic weather stations realized for all the brazilian territory.

Usage

tmin_calibration(slope, intercept, tmin_stack)

Arguments

slope	the slope of the linear regression (numeric)
intercept	the intercept of the linear regression (numeric)
tmin_stack	stack of maximum air temperature

Value

Returns a SpatRaster of calibrated minimum air temperature.

Examples

## Not run: 
tmin_cal<- tmin_calibrated(slope = 0.830652, intercept = 4.187840, tmin_stack = tmin);

## End(Not run)

---