Arizona and New Mexico receive half of their annual precipitation during the summer monsoon season, making this large-scale rain event critical for ecosystem productivity. We used the monsoon rains to explore the responses of soil bacterial and fungal communities to natural moisture pulses in a semiarid grassland. Through 454 pyrosequencing […]
Despite augmentation stocking efforts, wild populations of razorback suckers (Xyrauchen texanus) continue to decline. Endangered razorback suckers are commonly raised in off-channel ponds until maturity (approximately 300 mm TL) and then stocked into the Colorado River or its tributaries. After fish are stocked, they commonly move large distances downstream. We […]
Leaf retention is important in transferring energy from riparian trees to stream food webs. Retention increases with geomorphic complexity such as substrate coarseness, sinuosity, and the presence of debris dams. High discharge can reduce retention, particularly when streams lack physical trapping features. Travertine formations, caused by calcium carbonate deposition, can […]
Evapotranspiration (ET) comprises a major portion of the water budget in forests, yet few studies have measured or estimated ET in semi-arid, high-elevation ponderosa pine forests of the south-western USA or have investigated the capacity of models to predict ET in disturbed forests. We measured actual ET with the eddy […]
Fossil Creek Restoration Can we restore a river after a century of disturbance? Research in the Marks Lab has addressed the following questions: How did native species respond to restoration? Employing a BACI design (Before After Control Impact), we determined the relative importance of flow restoration versus non-native fish removal […]
Overview Fire, a natural ecological disturbance, has been suppressed in U.S. forests for much of the past century. This has prevented damage to property and protected timber resources, but has caused many forests to develop in an unnatural manner, resulting in dense stands of small trees that are now poised […]
Permafrost Carbon Network
Thousands of researchers worldwide are studying how global change affects ecosystems. Using models and field experiments, they add to our understanding of this area each day. However, individual studies sometimes only tell part of the whole story. By combining results from large numbers of studies, we can discern large-scale patterns across ecosystems, and make better estimates of how global change will affect our environment. Our work on global change synthesis combines several statistical techniques with modeling approaches. (more…)
Aquatic ecosystems in the southwestern US are among the most threatened in the country: rates of species loss are high, with few remaining refuges for natives, and water extraction for human use and diversion for power generation impose major demands on the defining feature of aquatic ecosystems: water. Work at […]
Early morning at the Carbon in Permafrost Experimental Heating Project (CiPEHR) in Alaska
Global change affects plants and soil in ecosystems across the globe. By doing so, it can alter the composition of ecosystems and the functions they provide. For instance, even small changes in plant growth and soil properties can have a large impact on the amount of CO2 and other greenhouse gases in the atmosphere. At Ecoss, we use field experiments to manipulate the temperature, rainfall and other environmental factors in various ecosystems. This allows us to mimic future conditions, and helps us understand how future ecosystems will differ from the ones today. (more…)
Northern Arizona University: PhD and MS positions in Ecosystem Ecology are available in the Center for Ecosystem Science in Society (Ecoss) at Northern Arizona University. The Ecoss mission is to conduct high-impact, innovative research on ecosystems and how they respond to and shape environmental change, to train next-gen scientists, and […]