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Southwest Biological Science Center
Modelling gully-erosion susceptibility in a semi-arid region, Iran: Investigation of applicability of certainty factor and maximum entropy models
Gully erosion susceptibility mapping is a fundamental tool for land-use planning aimed at mitigating land degradation. However, the capabilities of some state-of-the-art data-mining models for developing accurate maps of gully erosion susceptibility have not yet been fully investigated. This study assessed and...Azareh, Ali; Rahmati, Omid; Rafiei-Sardooi, Elham; Sankey, Joel B.; Lee, Saro; Shahabi, Himan; Bin Ahmad, Baharin
Fire changes the spatial distribution and sources of soil organic carbon in a grassland-shrubland transition zone
AimsIn many mixed grass-shrub ecosystems, increased shrub biomass tends to promote overall carbon storage, but the distribution of carbon pools may be complicated by disturbances such as wildfires. We investigated the spatial distribution of surface soil organic carbon (SOC) and its relative contribution from grasses and shrubs after fires in a...Wang, Guan; Li, Junran; Ravi, Sujith; Theiling, Bethany P.; Sankey, Joel B.
Land mollusks of the California Channel Islands: An overview of diversity, populations, and conservation status
The land snails and slugs have the highest level of endemism among all major animal groups on the California Channel Islands, with nearly 75% of the native terrestrial species confined to one or more of the 8 islands. In spite of this endemism, and in spite of the rarity of some species, the snails and slugs are one of the most poorly known groups...Drost, Charles A.; Nekola, Jeffrey C.; Roth, Barry; Pearce, Timothy A.
Remote sensing vegetation index methods to evaluate changes in greenness and evapotranspiration in riparian vegetation in response to the Minute 319 environmental pulse flow to Mexico
During the spring of 2014, 130 million m3 of water were released from the United States' Morelos Dam on the lower Colorado River to Mexico, allowing water to reach the Gulf of California for the first time in 13 years. Our study assessed the effects of water transfer or ecological environmental flows from one nation to another,...Nagler, Pamela L.; Jarchow, Christopher J.; Glenn, Edward P.
Biodiversity of amphibians and reptiles at the Camp Cady Wildlife Area, Mojave Desert, California and comparisons with other desert locations
We examined the biodiversity of amphibian and reptile species living in and near constructed ponds in the riparian area at the Camp Cady Wildlife Area (CCWA) in the Mojave Desert of San Bernardino County, California, based on field work from 1998-1999, 2016-2017, review of the literature, and searches for museum specimens using VertNet.org. A...Cummings, Kristy L.; Puffer, Shellie R.; Holmen, Jenny B.; Wallace, Jason K.; Lovich, Jeffrey E.; Meyer-Wilkins, Kathie; Petersen, Chris; Lovich, Robert E.
Influence of climate, post‐treatment weather extremes, and soil factors on vegetation recovery after restoration treatments in the southwestern US
AimsUnderstanding the conditions associated with dryland vegetation recovery after restoration treatments is challenging due to a lack of monitoring data and high environmental variability over time and space. Tracking recovery trajectories with satellite‐based vegetation indices can strengthen predictions of restoration outcomes across broad...Copeland, Stella M.; Munson, Seth M.; Bradford, John B.; Butterfield, Bradley J.
Examining forest structure with terrestrial lidar: Suggestions and novel techniques based on comparisons between scanners and forest treatments
Terrestrial laser scanners (TLSs) provide a tool to assess and monitor forest structure across forest landscapes. We present TLS methods, suggestions, and mapped guidelines for planning TLS acquisitions at varying scales and forest densities. We examined rates of point‐density decline with distance from two TLS that acquire data at relatively high...Donager, Jonathon J.; Sankey, Temuulen T.; Sankey, Joel B.; Sanchez Meadorc, Andrew J.; Springer, Abraham E.; Bailey, John D.
Agassiz’s desert tortoise (Gopherus agassizii) activity areas are little changed after wind turbine-induced fires in California
Wind turbine-induced fires at a wind energy facility in California, USA, provided an opportunity to study the before and after effects of fire on a population of protected Agassiz’s desert tortoises (Gopherus agassizii) in the Sonoran Desert, a species and ecosystem poorly adapted to fire. We compared annual activity areas (AAs) of tortoises in...Lovich, Jeffrey E.; Agha, Mickey; Ennen, Joshua R.; Arundel, Terence R.; Austin, Meaghan
Using research networks to create the comprehensive datasets needed to assess nutrient availability as a key determinant of terrestrial carbon cycling
A wide range of research shows that nutrient availability strongly influences terrestrial carbon (C) cycling and shapes ecosystem responses to environmental changes and hence terrestrial feedbacks to climate. Nonetheless, our understanding of nutrient controls remains far from complete and poorly quantified, at least partly due to a lack of...Vicca, Sara; Stocker, Benjamin; Reed, Sasha C.; Wieder, William R.; Bahn, Michael; Fay, Philip A.; Janssens, Ivan; Lambers, Hans; Penuelas, Josep; Piao, Shilong; Rebel, Karin; Sardans, Jordi; Sigurdsson, Bjarni D.; Van Sundert, Kevin; Wang, Ying-Ping; Zaehle, Sonke; Ciais, Philippe
Chronic physical disturbance substantially alters the response of biological soil crusts to a wetting pulse, as characterized by metatranscriptomic sequencing
Biological soil crusts (biocrusts) are microbial communities that are a feature of arid surface soils worldwide. In drylands where precipitation is pulsed and ephemeral, the ability of biocrust microbiota to rapidly initiate metabolic activity is critical to their survival. Community gene expression was compared after a short duration (1 hour)...Steven, Blaire; Belnap, Jayne; Kuske, Cheryl R.
Are fungal networks key to dryland primary production?
In low-resource ecosystems, competition among primary producers can be reduced through the partitioning of limiting resources in space or time. Partitioning, coupled with species interactions, can be a source of ecosystem stability by retaining resources within a biotic “loop” and slowing losses due to physical processes, such as erosion, gaseous...Rudgers, Jennifer A.; Dettweiler-Robinson, Eva; Belnap, Jayne; Green, Laura E.; Sinsabaugh, Robert L.; Young, Kristina E.; Cort, Catherine E.; Darrouzet-Nardi, Anthony
Adapting management to a changing world: Warm temperatures, dry soil, and interannual variability limit restoration success of a dominant woody shrub in temperate drylands
Restoration and rehabilitation of native vegetation in dryland ecosystems, which encompass over 40% of terrestrial ecosystems, is a common challenge that continues to grow as wildfire and biological invasions transform dryland plant communities. The difficulty in part stems from low and variable precipitation, combined with limited understanding...Shriver, Robert K.; Andrews, Caitlin M.; Pilliod, David S.; Arkle, Robert; Welty, Justin; Germino, Matthew J.; Duniway, Michael C.; Pyke, David A.; Bradford, John B.