Projecting and Modeling Ecosystem Change

We are combining high-resolution spatial imagery with ground-collected data to create detailed classification maps of native and non-native plants on Lāna‘i. We are also using the high-resolution maps, historical satellite and aerial imagery to analyze changes in ‘ua‘u - Hawaiian petrel - nesting habitat. For the first time at island scales in Hawai’i, this species-level mapping uses high...

Recent studies show that past and ongoing environmental changes have been substantial and have likely already affected conservation efforts in Hawai‘i. Much of the state has experienced substantial drying, including decreases in mean annual precipitation since the 1920s, longer rainless periods, and decreasing stream flow. Temperatures have been increasing in Hawai‘i for the last 40 years...

Climate change is expected to alter the seasonal and annual patterns of rainfall and temperature in the Hawaiian Islands. Warming temperatures and altered precipitation patterns both impact ecological systems, but managing these impacts is difficult without detailed information on the magnitude and timing of these climate-related changes.

Hawai‘i's precipitation is greatest in upland areas that are typically forested. This precipitation provides water for both people and ecosystems. Precipitation can either run off and contribute to streamflow, or infiltrate into the ground and provide water for plants, base flow to streams, or recharge to aquifers. The exact routing that water takes is controlled by many factors, including the...

Remote locations, rugged topography, extreme weather conditions, high numbers of threatened and endangered taxa, and widespread degradation of native ecosystems by invasive species makes routine monitoring to determine status and trends of ecosystems and native and invasive taxa difficult and expensive in the Hawaiian Islands. There is a need to supplement existing monitoring protocols with more...

Within a context of human-mediated land cover change, invasive competitors, predators and disease, conservation biologists and practitioners are now concerned that climate change will further impact the beleaguered flora and fauna of the Pacific Islands. Across the region and elsewhere, to determine these potential impacts of climate change on species and ecosystems, research efforts have focused...

Initial studies suggest terrestrial Hawaiian plant species may be vulnerable to climate change. However, these models lack information on species-specific traits that affect ecological and evolutionary responses of species to climate change. Research is needed to refine current vulnerability models and apply these to Pacific Islands outside Hawai‘i.

Montane plant communities in widely separated intact natural environments of the world have responded to changes in precipitation and temperature regimes by shifting both margins and core distributional ranges upward in elevation. Reduced evapotranspiration rates in cooler climate zones at higher elevation may compensate for less precipitation and higher temperatures within species’ former ranges...

In recent years, the U.S. Geological Survey has been conducting a national biologic carbon sequestration assessment in the conterminous U.S. The assessment is designed to meet the requirements of the Energy Independence and Security Act of 2007, which calls for coverage of all 50 states and all ecosystems (including forests, grasslands, wetlands, agricultural lands, and rivers, lakes, and...

One of the impacts of global climate change for the Hawaiian Islands is a projected increase in sea level of about one meter by the year 2100. This change will impact both biological and cultural resources located along the coastline. Few intact native coastal and lowland plant communities remain in Hawai‘i. Many of those that remain contain listed endangered species and provide important habitat...

Hawaiian forests are beset by many stressors, resulting in a complex pattern of altered ecosystems, impeirled species, and (in some areas) substantial protection and restoration. Short-term studies focused on specific sites or biota have limited value in understanding landscape-level change. Long-term and spatialy extensive data are needed to understand how ecosystems are reacting to both stressor...

Because of the extreme climate gradients in Hawai‘i, relatively small shifts in atmospheric circulation can cause major changes in rainfall, cloud cover, and humidity. Because it has been shown that cloud water forms an important input at specific sites, we need to understand how these inputs vary across the landscape, or how interactions with plant communities alter direct inputs. Such changes...