Overview

• Mapping crop types and crop and grassland area estimation.
• Identification of crop phenological stages (focus on maize).
• Yield and above ground biomass estimation.
• Monitoring the impact of extreme weather events on crop health and stress (focus on drought).

 

Project Objectives

Site Description

Landscape Topography	The JECAM site Twente has an average terrain height of 31.9 m asl (minimum 3 m asl and maximum of 93m asl). The nested core zone has an average terrain height of 27.6 m asl (minimum 12m asl and maximum 49 m asl). The site has a diverse bocage landscape combining grassland, cropland and woodland areas but also urban areas and natural features like fens and heathland.
Typical Field Size	Average field size for cropland is 2.59 ha and average field size for grassland is 2.63 ha (both averages based on the year 2023).
Climatic Zone	The Twente site experiences an oceanic climate (Cfb in Köppen climate classification) with cold summers and relatively mild winters, characterized by moderate precipitation throughout the year.
Major Crops and Calendars	Maize (Normal): Calendar: April - September Grassland and Meadows (Normal): Mixed cereals (Normal):
Soil Type & Texture	Organic: Humic Inorganic: Sand Loamy Sand
Soil Drainage Class
Irrigation Infrastructure	Permanent irrigation is not very common, but supplementary irrigation is applied in dry periods on farms that have access to ground- or surface water.
Other Site Details	The site holds significance as a cross-boundary area, facilitating the comparison between the predominant maize and grassland-based agriculture in the Twente region of the Netherlands and the more diverse crop agriculture on the German side, including also the cultivation of multiple cereals. In addition to agricultural fields, the site encompasses protected areas (heathland and fens) and well-maintained grass surfaces (Twente airport and several golf courses, serving as valuable reference points for assessing crop water stress) as well as several large water bodies.

In Situ Observations

Student surveys and Citizen Science information:

• Crop Type(s): Maize, Grassland and Meadows
• Collection Protocol:
  • Collection Protocol:
    • Students of ITC and University of Twente collect data in numerous compulsory and elective courses in the nested core zone of the JECAM site. In particular, land cover data but also crop parameters such as crop height, above ground biomass and yield as well as other information on agricultural management activities can be collected.
    • Existing collaborations to professional farmers and citizen farmers will be strengthened and further collaborations with farmer’s associations established. Information on the impact of climate change and extreme weather events on agriculture is collected in project related workshops and provided as qualitative data.
• Frequency: Once per year.

Meteorological measurements

• Crop Type(s): Maize, Grassland and Meadows, Fruit-bearing vegetables
• Collection Protocol:
  • Collection Protocol:
    • After an initial testing phase in 2023, we will now incrementally increase our measurement network of connected open-source meteorological stations. We envision 3-5 functional stations in the JECAM site in the coming years related to different projects as well as a calibration site for meteorological measurements on University of Twente campus. The stations are connected to the University of Twente sensor data base using a near-real time data link based on LoRaWAN technology. Meteorological variables measured are air humidity and temperature, precipitation, wind speed and direction as well as soil moisture components. A collaboration with the Twente Soil Moisture Network (5 active measurement locations in the JECAM site) is established and will add further water and vegetation related information.
• Frequency: Once per year as a dataset. We will explore options for an on-demand download option.

Field cameras:

• Crop Type(s): Maize, Grassland and Meadows, Fruit-bearing vegetables
• Collection Protocol:
  • Collection Protocol:
    • Two PhenoCams (utwente1 and utwente2) are available in the JECAM site area (both within the nested core zone) with footprints covering grassland, maize and forests.
    • After a testing phase in 2023 we will initiate the establishment of a medium resolution monitoring network using thermal field cameras. The focus of the first set of cameras will be agricultural land in the nested core zone. The land surface temperatures collected with these cameras will be used in the calibration of satellite imagery to determine the crop water stress.
    • We initiated the establishment of a field camera monitoring network designed to capture daily images of key cropping areas. The primary emphasis will be on monitoring maize and/or vegetable cultivations. The data collected will be used in conjunction with satellite based vegetation indices to determine phenological phases of maize and cover crops.
• Frequency: PhenoCams can be accessed via website. Non-connected field camera data is collected and emitted once per year as a dataset. We are currently exploring options to transmit field camera data using GSM infrastructure and will explore options for an on-demand download option.

UAV/drone mapping missions:

• Crop Type(s): Maize, Grassland and Meadows, Fruit-bearing vegetables
• Collection Protocol:
  • Collection Protocol:
    • UAV/drone based field data collection to record high resolution field data in the spatially nested core zone will be conducted in conjunction with local scientific projects, collaborations with local farmers and as part of the student surveys (see above). The method called “drone truthing” will provide high resolution calibration and reference data for satellite image based crop detection and mapping approaches.
• Frequency: UAV data will be collected and processed throughout the year. UAV data in different processing stages (raw images, orthomosaics, analysis products) is collected and key data sets are emitted once per year.

EO Data

Optical Data Requirements

Approximate Start Date of Acquisition: 01/01

Approximate End Date of Acquisition: 31/12

Spatial resolution: Medium resolution (20-60m)High resolution (5-20m)Very high resolution (below 5m)

temporal_frequency: WeeklyBiweekly

Level of Expertise: Intermediate

Latency of Data Delivery: More than 5 days

Challanges:

SAR Data Requirements

Passive Microwave Data Requirements

Thermal Data Requirements

Results

Documents and Files

Links to paper

• Documents and Files: (will be updated)
• Links to paper: (will be updated)

Project Reports

Generate

Study Team

Team Leader

Name: Florian J. Ellsäßer

Affiliation: Department of Natural Resources, ITC, University of Twente

Affiliation Webpage: https://www.itc.nl/

Position: Assistant professor

Email: f.j.ellsaesser@utwente.nl

Personal Webpage:

Phone number:

Postal Address: Hallenweg 8, 7522 NH, Enschede, Netherlands

Other Team Members

Name: Anton Vrieling

Affiliation: Department of Natural Resources, ITC, University of Twente

Affiliation Webpage: https://www.itc.nl/

Position: Associate professor

Email: a.vrieling@utwente.nl

Personal Webpage:

Role: Member

Name: Andy Nelson

Affiliation: Department of Natural Resources, ITC, University of Twente

Affiliation Webpage: https://www.itc.nl/

Position: Full professor

Email: a.nelson@utwente.nl

Personal Webpage:

Role: Member

Name: Iris van Duren

Affiliation: Department of Natural Resources, ITC, University of Twente

Affiliation Webpage: https://www.itc.nl/

Position: Assistant professor

Email: i.c.vanduren@utwente.nl

Personal Webpage:

Role: Member

Name: Valentijn Venus

Affiliation: Department of Natural Resources, ITC, University of Twente

Affiliation Webpage: https://www.itc.nl/

Position: Lecturer and researcher

Email: v.venus@utwente.nl

Personal Webpage:

Role: Member