Variability in gross primary productivity of native and managed pastures to climatic variability and management practices
Abstract
Future climates in the US Southern Plains are expected to have larger variability in weather elements, especially rainfall. However, the degree and timing of climate variability that affect productivity of pasture managed differently have not been well studied. We examined the impacts of climate variability on grassland productivity using 17 years of gross primary productivity (GPP) for co-located native and managed pastures of Oklahoma. We also considered the interactive effects of management factors and climate variability into the regression models and identifed the critical climate windows (CCW) that influence annual variability in GPP. Managed pasture (MP) showed greater variability of GPP than did native pasture (NP), particularly with reduced GPP in drought years. The resilience of native grasses under unfavorable climate extremes was evident by lower GPP anomalies in NP than MP during the 2011-2012 drought. Although both pastures experienced the same degree of climate variability, the CCW affecting GPP was significantly different between NP and MP due to the modulating impact of management practices on the responses of MP. Not only the range but also the timing of the CCW was different between NP and MP as MP was more responsive to the spring temperature and fall rainfall. Our findings warrant the incorporation of MP as a different commodity from NP when accounting for the ecosystem responses to climate variability in global climate models.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.B32A..08B
- Keywords:
-
- 0402 Agricultural systems;
- BIOGEOSCIENCES;
- 0480 Remote sensing;
- BIOGEOSCIENCES;
- 1616 Climate variability;
- GLOBAL CHANGE;
- 1632 Land cover change;
- GLOBAL CHANGE