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Non-crop vegetation, such as hedgerows and cover crops, are important on-farm diversification practices that support biodiversity and ecosystem services; however, information about their rates and patterns of adoption are scarce. We used satellite and aerial imagery coupled with machine learning classification to map the use of hedgerows/windbreaks and winter cover crops in California's Central Coast, a globally important agricultural area of intensive fresh produce production. We expected that adoption of both practices would be relatively low and unevenly distributed across the landscape, with higher levels of adoption found in marginal farmland and in less intensively cultivated areas where the pressure to remove non-crop vegetation may be lower. Our remote sensing classification revealed that only ~6% of farmland had winter cover crops in 2021 and 0.26% of farmland had hedgerows or windbreaks in 2018. Thirty-seven percent of ranch parcels had cover crops on at least 5% of the ranch while 22% of ranches had at least one hedgerow/windbreak. Nearly 16% of farmland had other annual winter crops, some of which could provide services similar to cover crops; however, 60% of farmland had bare soil over the winter study period, with the remainder of farmland classified as perennial crops or strawberries. Hotspot analysis showed significant areas of adoption of both practices in the hillier regions of all counties. Finally, qualitative interviews revealed that adoption patterns were likely driven by interrelated effects of topography, land values, and farming models, with organic, diversified farms implementing these practices in less ideal, lower-value farmland. This study demonstrates how remote sensing coupled with qualitative research can be used to map and interpret patterns of important diversification practices, with implications for tracking policy interventions and targeting resources to assist farmers motivated to expand adoption.
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Potential nitrogen mineralization in Alabama soils
Nitrogen (N) transformation in soils is crucial in determining N availability for plant growth. Row crop producers have widely adopted cover crops across the U.S. However, there is limited knowledge about N transformations in commercial fields with and without cover crops. Furthermore, there is lack of understanding about the spatial variability of potential N mineralization in row crops and how it varies within a field and between cropping systems. An in-situ mineralization study was conducted in two Alabama row crop farms to evaluate the variability of potential N mineralization across locations and within a farm. The results revealed the variability in N mineralization within farms at both the locations. It was reported that a farm with cover crop and residue retention history had a mineralization rate of 1.18 to 3.89 lb/acre/day. In contrast, another farm with no cover crop had a mineralization potential of 0.93 to 1.17 lb/acre/day. These findings underscore the importance of cover crops and residue retention for enhancing N mineralization potential.
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- Award ID(s):
- 1922687
- PAR ID:
- 10529335
- Publisher / Repository:
- National Association County Agricultural Agents
- Date Published:
- Journal Name:
- Journal of the NACAA
- ISSN:
- 2158-9429
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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