Spatio‐Temporal Patterns of Open Surface Water in the Central Valley of California 2000‐2011: Drought, Land Cover, and Waterbirds

Abstract

We used Landsat satellite imagery to (1) quantify the distribution of open surface water across the Central Valley of California 2000-2011, (2) summarize spatio-temporal variation in open surface water during this time series, and (3) assess factors influencing open surface water, including drought and land cover type. We also applied the imagery to identify available habitat for waterbirds in agriculture. Our analyses indicated that between 2000 and 2011 open surface water has declined across the Central Valley during the months of July-October. On average, drought had a significant negative effect on open surface water in July, September, and October, though the magnitude and timing of the effect varied spatially. The negative impact of a drought year on open water was experienced immediately in the southern Central Valley; however, there was a one year time-lag effect in the northern Central Valley. The highest proportion of open surface water was on agricultural lands followed by lakes, rivers, and streams, yet the relative proportions varied spatially and across months. Our data were consistent with previous descriptions of waterbird habitat availability in post-harvest rice in the northern Central Valley. Tracking water distribution using satellites enables empirically based assessments of the impacts of changing water policy, land-use, drought, climate, and management on water resources.

Three decades of Landsat-derived spring surface water dynamics in an agricultural wetland mosaic; Implications for migratory shorebirds

“…There is great potential for tracking long-term surface water dynamics given Landsat's <16-day revisit period from 1983 to the present (e.g., Feng et al, 2016;Mueller et al, 2016;Tulbure et al, 2016). The presence and duration of flooding can be informative in lieu of more intensive field measurements (Elphick, 2008;Farmer and Parent, 1997;Reiter et al, 2015). For example, these attributes influence invertebrate prey densities, which are challenging to measure precisely in situ over large areas (Batzer, 2013;Lee et al, 1999;Lyzenga et al, 2006).…”

Impact of extreme drought and incentive programs on flooded agriculture and wetlands in California’s Central Valley

“…However, provisioning these crops and wetlands as waterbird habitat is dependent on a highly managed water system, and the availability of water is dynamic (Reiter et al 2015;Reynolds et al 2017). xlimate change projections suggest that the inter-annual variability in the amount of waterbird habitat may increase with time, even if long-term declines in average precipitation are not projected to be substantial (Matchett & Fleskes 2017), making understanding how to manage through extremes critically important.…”

“…To better characterize the magnitude and impacts of the recent severe drought and to assess the relative contribution of flooded habitat as the result of incentive programs, analyses of more recent data compared to longer-term estimates (2000-2011Reiter et al 2015) of water extent were needed. Hence, our objectives with this study were to: …”

Impact of extreme drought and incentive programs on flooded agriculture and wetlands in California’s Central Valley

“…xlimate change projections suggest that the inter-annual variability in the amount of waterbird habitat may increase with time, even if long-term declines in average precipitation are not projected to be substantial (Matchett & Fleskes 2017), making understanding how to manage through extremes critically important. Reiter et al 2015). The recent extreme and multi-year drought affecting xalifornia provides opportunity to gain additional insights into how more prolonged and extreme variations in the hydrology of the Sacramento and San-Joaquin watersheds may influence the distribution of waterbird habitat.…”

“…Previous analysis of xentral Valley water availability quantified the extent of open surface water in the xentral Valley between July and December for 2000 -2011 (Reiter et al 2015). To better characterize the magnitude and impacts of the recent severe drought and to assess the relative contribution of flooded habitat as the result of incentive programs, analyses of more recent data compared to longer-term estimates (2000-2011Reiter et al 2015) of water extent were needed.…”