Non-photosynthetic vegetation (NPV) is plant material that has no photosynthetic function, such as dead biomass, surface litter, and woody stems. NPV serves an ecologically beneficial role; in the agricultural setting, maintaining crop residue on the soil surface reduces erosion, improves soil structure, maintains stable temperatures, and increases soil carbon, all of which support the health of farming systems.
Temporal Trends in Agricultural Water Use and the Relationships to Hydroclimatic Factors in the High Plains Aquifer Region
The High Plains Aquifer (HPA) is the primary water source for irrigated agriculture in the Great Plains of the United States. However, water levels in many locations of the aquifer have declined steadily over the past several decades because the rate of water withdrawals exceeds the rate of aquifer recharge. The decline of the groundwater table has been a serious concern to farmers and local governments in the HPA region as crop production is heavily dependent on the groundwater source.
Aspen (Populus tremuloides) forests are keystone ecosystems in the western United States that supply economic and social benefits, including drawing tourists, serving as potential fire breaks, improving local economies, and providing habitat and forage for wildlife and livestock. However, in many areas these forests are at risk from climate change and past land use.
Seagrasses, which are submerged marine plants, have been declining globally at increasing rates. This downward trend is concerning because seagrasses provide numerous ecosystem services including nutrient cycling, sediment stabilization, wave attenuation, and carbon sequestration. Furthermore, they are important habitat for recreationally and commercially fished marine species, including many species of shellfish, finfish, crabs, and shrimp.
High water levels and heavy wave action have degraded shoreline, beaches, and infrastructure along the Lake Superior side of the Minnesota Point barrier island, located between the Duluth and Superior Harbor entries. The U.S. Army Corps of Engineers (USACE) has been exploring the beneficial use of dredge material for beach nourishment on the barrier island to slow the impact of erosion.
Coastal wetlands and estuaries are critical ecosystems that serve as the bridge between land and sea, provide habitat for numerous species of fish and wildlife, and offer protection from storms and waves for inland communities. When these environments evolve naturally, they can adapt to rising sea levels by retreating landward, and fish and wildlife follow suit.
Microbial biofilm communities, which are comprised of bacteria, diatoms, protozoa, and fungi, inhabit the surface of intertidal mudflats. These communities represent a large proportion of shorebirds’ diets, so understanding biofilm distribution, quantity, and nutritional value supports efforts to manage shorebird populations.
The island of Puerto Rico is subject to numerous natural hazards including hurricanes, coastal erosion, and flooding. Information on how the island’s coastal environments respond to these events is critical for bolstering coastal resilience.
The Nation’s coastlines are highly dynamic ecosystems that can change drastically in response to storms, high water levels, and sea-level rise. These changes can put habitats, lives, and infrastructure at risk. The U.S. Geological Survey (USGS) has the expertise and capabilities to measure these coastlines and predict where and when coastal change may occur, but updated coastal elevation data are needed to keep these forecasts as accurate as possible.
California recently experienced one of the most severe droughts in its history, resulting in extensive dieback of chaparral vegetation in the State’s Mediterranean regions. Though chaparral species are adapted to annual summer drought, the duration or intensity of a drought may exceed the adaptive capabilities of even these plants. The impacts of the recent severe drought were further exacerbated in many chaparral ecosystems by the occurrence of wildfires.