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Credit: Gordan Campbell at Altitude GalleryOver the last 30 years, nearly half of the upland area on the barrier islands has changed from grassland to shrub thickets, similar to transitions observed in other drylands. For coastal systems, this transition is driven by regional climate (higher winter temperatures, lower precipitation) and shrub feedbacks on microclimate (warmer… Read more »

Credit: Erika ZambelloLong term VCR LTER and comparative studies define a threshold sea-level rise rate beyond which marshes cannot keep pace and drown. An early warning indicator of this state change is an increase in recovery time following flooding disturbances. Storms cause marsh loss by erosion in proportion to wave energy at the marsh edge…. Read more »

Credit: Gordan Campbell at Altitude GalleryHistorically, this undeveloped landscape has been a shifting mosaic; a new 30-year retrospective now shows directional change and accelerating ecosystem loss. Barrier island upland area has declined by a third, and island marsh loss due to storm overwash has increased, especially in the last decade. Feedbacks between vegetation and sediment… Read more »

Agriculture emits quantities of greenhouse gases equivalent to those from the transportation sector, and long term LTER research has revealed how farmers can better manage intensive row crop systems to mitigate climate change. Plant-microbe-soil interactions can enhance soil carbon sequestration, reduce nitrous oxide emissions, and promote methane oxidation. Implemented widely, improved management could make cropping… Read more »

Twenty-plus years of nitrogen fertilization have caused rhizobia in soybeans to evolve toward reduced nitrogen fixation. These evolutionary changes have ecological consequences, as the evolution of reduced cooperation alters soil nitrogen availability. Directed changes to the microbial community, through plant-soil management or added bioinoculants, represents an important frontier for improving cropping system resilience.  

Simplification of agricultural landscapes reduces abundance of predatory insects, at substantial cost to farmers and society. Diverse landscapes harbor generalist predators such as ladybird beetles, which control crop pests such as soybean aphids, limiting the need for insecticide use. Given global declines in insect abundance, increasing the diversity of habitats and their spatial arrangement across… Read more »

Old-growth forest-stream ecosystems store enormous amounts of carbon. Andrews LTER researchers found that forest biomass accumulated at relatively linear rates over a century – counter to theoretical predictions that biomass accumulation would slow during forest succession. They also found that climate change related mortality at Andrews is low compared to other forests in the western… Read more »

Credit: AND LTERDue to increased shading from forest regrowth, streams in recovering forest experience declining temperatures, despite a warming climate. Site history is essential to correctly interpreting climate change response to such trends.  

Credit: Lina DiGregorioCross-site comparisons reveal varying long term trends in nitrogen exports, and varying responses to warming trends. Although theory predicts that streamflow should recover quickly after disturbance, paired watershed comparisons found decreases in summer flow (relative to undisturbed watersheds) in regenerating post-harvest forests 25 to 45 years old.