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Agricultural activities have been recognized as an important driver of land cover and land use change (LCLUC) and have significantly impacted the ecosystem feedback to climate by altering land surface properties. A reliable historical cropland distribution dataset is crucial for understanding and quantifying the legacy effects of agriculture-related LCLUC. While several LCLUC datasets have the potential to depict cropland patterns in the conterminous US, there remains a dearth of a relatively high-resolution datasets with crop type details over a long period. To address this gap, we reconstructed historical cropland density and crop type maps from 1850 to 2021 at a resolution of 1 km × 1 km by integrating county-level crop-specific inventory datasets, census data, and gridded LCLUC products. Different from other databases, we tracked the planting area dynamics of all crops in the US, excluding idle and fallow farm land and cropland pasture. The results showed that the crop acreages for nine major crops derived from our map products are highly consistent with the county-level inventory data, with a residual less than 0.2×103 ha (0.2 kha) in most counties (>75 %) during the entire study period. Temporally, the US total crop acreage has increased by 118×106 ha (118 Mha) from 1850 to 2021, primarily driven by corn (30 Mha) and soybean (35 Mha). Spatially, the hot spots of cropland distribution shifted from the Eastern US to the Midwest and the Great Plains, and the dominant crop types (corn and soybean) expanded northwestward. Moreover, we found that the US cropping diversity experienced a significant increase from the 1850s to the 1960s, followed by a dramatic decline in the recent 6 decades under intensified agriculture. Generally, this newly developed dataset could facilitate spatial data development, with respect to delineating crop-specific management practices, and enable the quantification of cropland change impacts on the environment. Annual cropland density and crop type maps are available at https://doi.org/10.6084/m9.figshare.22822838.v2 (Ye et al., 2023).
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Annual time-series 1-km maps of crop area and types in the conterminous US (CropAT-US) during 1850-2021
By integrating multi-source cross-scale inventories and satellite-based datasets, we reconstructed the annual crop density and crop type map (excluding summer idle/fallow, cropland pasture) in the contiguous US at 1km×1km resolution from 1850 to 2021. The annual crop density map depicts the distribution and fraction of cultivated land, while the crop type map displays the corresponding crop type. The developed datasets fill the data gap in lacking of crop type extent and type maps, which can support the environmental assessment and socioeconomic analysis related to agricultural activities. (Supplement to: Shuchao, Ye et al. (2023): Annual time-series 1-km maps of crop area and types in the conterminous US (CropAT-US): cropping diversity changes during 1850-2021.)
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- Award ID(s):
- 1945036
- PAR ID:
- 10590595
- Publisher / Repository:
- figshare
- Date Published:
- Subject(s) / Keyword(s):
- Agricultural spatial analysis and modelling Earth system sciences
- Format(s):
- Medium: X Size: 2230290326 Bytes
- Size(s):
- 2230290326 Bytes
- Right(s):
- Creative Commons Attribution 4.0 International
- Sponsoring Org:
- National Science Foundation
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