Land use for grain production

[summon]

Hello, I’m a beginner.
I’m learning the grain production module of the investment model. In the land use file of the water production module, the grain crops are only divided into a large category. When focusing on the grain module, do you need to reprocess the grid map?
I try to find the grid map of vegetation cover and change the attribute table to clearly divide the types of food crops. I don’t know whether this is the correct operation. Do you have any good suggestions?

[swolny]

Hi @summon -

Which InVEST model are you using? Perhaps Annual Water Yield or Seasonal Water Yield?

Both of these models require a land use/land cover (LULC) map that completely covers the whole area of interest that you’re studying. So even if you want to focus on grains, your LULC map should also include all of the land use/land cover types that are in your area of study (which might be urban, forest, other crops, etc).

Your LULC map may have whatever number of classes and types of classes that are needed for your study. So you may have a single “grain” class if that’s appropriate for your study, or multiple classes for different types of grain crops. Regardless of how many classes you have, or which types of classes you have, you’ll need to include all of them in the biophysical table that contains parameters related to each class, and you’ll need to assign values to all of them, as described in the User Guide.

How you create the appropriate LULC map and classifications will depend on the data that you have. You may need to combine multiple data layers into one. For example, if you have an LULC map that just has a single “grains” class, and you have a second map that has different kinds of grains defined, you can combine these using your GIS skills.

~ Stacie

[summon]

Hello, swolny
Sorry, because I can’t open the website for the time being, I didn’t send a public topic. When I was learning the crop yield module, I encountered the following error reporting problem. I tried to reprocess the chart and table, but it didn’t solve it. Do you have any better suggestions?
Good luck

---- 回复的原邮件 ----

发件人 | Stacie Wolny via Natural Capital Project Online Communitynotifications@naturalcapitalproject.discoursemail.com |

• | - |
  日期 | 2022年03月31日 22:46 |
  收件人 | 13598052182@163.com13598052182@163.com |
  抄送至 | |
  主题 | [Natural Capital Project Online Community] Land use for grain production |

| swolny
March 31 |

• | - |

Hi @summon -

Which InVEST model are you using? Perhaps Annual Water Yield or Seasonal Water Yield?

Both of these models require a land use/land cover (LULC) map that completely covers the whole area of interest that you’re studying. So even if you want to focus on grains, your LULC map should also include all of the land use/land cover types that are in your area of study (which might be urban, forest, other crops, etc).

Your LULC map may have whatever number of classes and types of classes that are needed for your study. So you may have a single “grain” class if that’s appropriate for your study, or multiple classes for different types of grain crops. Regardless of how many classes you have, or which types of classes you have, you’ll need to include all of them in the biophysical table that contains parameters related to each class, and you’ll need to assign values to all of them, as described in the User Guide.

How you create the appropriate LULC map and classifications will depend on the data that you have. You may need to combine multiple data layers into one. For example, if you have an LULC map that just has a single “grains” class, and you have a second map that has different kinds of grains defined, you can combine these using your GIS skills.

~ Stacie

[swolny]

Hi @summon -

In the error message, it looks like you may have specified a value of " corn" in the crop mapping table, but there is no “corn” map, it is called “maize” or “maizefor” (the latter might be forage? I’m not sure.) There is a list of supported crops in the User Guide, which I know is actually missing a few, but “maize” is in there. You can also look in the input data folders in the sample data “model_data” folder to see all of the supported crops.

Also, just a note that if you look closely, it appears that there is a space in front of the c, so " corn" instead of “corn” without a space in front. I’m not sure if this is would cause an error with InVEST, but it might, so be sure to remove any spaces before or after the crop name in the table.

~ Stacie

[summon]

Thank you, swolny.
I took a closer look, changed corn to maize, and the problem was solved.
Thank you so much for your help!

---- 回复的原邮件 ----

发件人 | Stacie Wolny via Natural Capital Project Online Communitynotifications@naturalcapitalproject.discoursemail.com |

• | - |
  日期 | 2022年04月05日 00:05 |
  收件人 | 13598052182@163.com13598052182@163.com |
  抄送至 | |
  主题 | [Natural Capital Project Online Community] [NatCap Software Support] Land use for grain production |

| swolny
April 4 |

• | - |

Hi @summon -

In the error message, it looks like you may have specified a value of " corn" in the crop mapping table, but there is no “corn” map, it is called “maize” or “maizefor” (the latter might be forage? I’m not sure.) There is a list of supported crops in the User Guide, which I know is actually missing a few, but “maize” is in there. You can also look in the input data folders in the sample data “model_data” folder to see all of the supported crops.

Also, just a note that if you look closely, it appears that there is a space in front of the c, so " corn" instead of “corn” without a space in front. I’m not sure if this is would cause an error with InVEST, but it might, so be sure to remove any spaces before or after the crop name in the table.

~ Stacie