{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,17]],"date-time":"2025-12-17T12:55:43Z","timestamp":1765976143914,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2016,12,1]],"date-time":"2016-12-01T00:00:00Z","timestamp":1480550400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Pasture biomass is an important quantity globally in livestock industries, carbon balances, and bushfire management. Quantitative estimates of pasture biomass or total standing dry matter (TSDM) at the field scale are much desired by land managers for land-resource management, forage budgeting, and conservation purposes. Estimates from optical satellite imagery alone tend to saturate in the cover-to-mass relationship and fail to differentiate standing dry matter from litter. X-band radar imagery was added to complement optical imagery with a structural component to improve TSDM estimates in rangelands. High quality paddock-scale field data from a northeastern Australian cattle grazing trial were used to establish a statistical TSDM model by integrating optical satellite image data from the Landsat sensor with observations from the TerraSAR-X (TSX) radar satellite. Data from the dry season of 2014 and the wet season of 2015 resulted in models with adjusted r2 of 0.81 in the dry season and 0.74 in the wet season. The respective models had a mean standard error of 332 kg\/ha and 240 kg\/ha. The wet and dry season conditions were different, largely due to changed overstorey vegetation conditions, but not greatly in a pasture \u2018growth\u2019 sense. A more robust combined-season model was established with an adjusted r2 of 0.76 and a mean standard error of 358 kg\/ha. A clear improvement in the model performance could be demonstrated when integrating HH polarised TSX imagery with optical satellite image products.<\/jats:p>","DOI":"10.3390\/rs8120989","type":"journal-article","created":{"date-parts":[[2016,12,2]],"date-time":"2016-12-02T10:36:37Z","timestamp":1480674997000},"page":"989","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Integration of Optical and X-Band Radar Data for Pasture Biomass Estimation in an Open Savannah Woodland"],"prefix":"10.3390","volume":"8","author":[{"given":"Michael","family":"Schmidt","sequence":"first","affiliation":[{"name":"Queensland Department of Science, Information Technology and Innovation, GPO BOX 5078, Brisbane QLD 4102, Australia"}]},{"given":"John","family":"Carter","sequence":"additional","affiliation":[{"name":"Queensland Department of Science, Information Technology and Innovation, GPO BOX 5078, Brisbane QLD 4102, Australia"}]},{"given":"Grant","family":"Stone","sequence":"additional","affiliation":[{"name":"Queensland Department of Science, Information Technology and Innovation, GPO BOX 5078, Brisbane QLD 4102, Australia"}]},{"given":"Peter","family":"O\u2019Reagain","sequence":"additional","affiliation":[{"name":"Department of Agriculture and Fisheries, P.O. Box 976, Charters Towers, QLD 4820, Australia"}]}],"member":"1968","published-online":{"date-parts":[[2016,12,1]]},"reference":[{"key":"ref_1","unstructured":"Werner, A. (1991). Savanna Ecology and Management, Australian Perspectives and International Comparisons, Blackwell Scientific Publications."},{"key":"ref_2","unstructured":"McKeon, G.M. (2004). Pasture Degradation and Recovery in Australia\u2019s Rangelands: Learning from History."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"665","DOI":"10.2134\/agronj1997.00021962008900040020x","article-title":"Determination of pasture biomass using four indirect methods","volume":"89","author":"Harmoney","year":"1997","journal-title":"Agron. J."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"GL Hammer, N.N., and Mitchell, C.D. (2000). 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