Background and Rationale Aquatic ecosystems in urban environments are highly modified by human activity, engineering, and design. These systems are critical in delivering ecosystem services to urban residents, who comprise over 80% of the US population. This synthesis working group builds upon two impromptu meetings of interested persons held at the 2012 ASM[1]. Based upon… Read more »
Summary We request funds for a working group to synthesize existing data within the LTER network on nitrogen mineralization and nitrification, soil respiration and soil moisture and to develop protocols for a new tightly coordinated, network-wide effort to develop a long-term data stream on these variables. The primary activity would be a workshop to be… Read more »
Background: The potential for abrupt transitions in ecosystem processes may increase as climate change continues to accelerate1,2. While this trend is of great concern, our understanding of how to identify when and why abrupt transitions occur has been informed almost exclusively by theory. In order to enhance the prediction and management of these changes for… Read more »
This working group will support the next stage of development for a LTER network-based system called Veg-DB that would provide improved access to vegetation data. LTER sites have become significant reservoirs of long-term data on changes in vegetation populations, structure, composition, and productivity. This information is essential to detect long-term trends, test hypotheses, and to… Read more »
Predictions regarding future climate change vary greatly among regions, and these predictions include directional changes such as more arid conditions in the US Southwest (Seager et al. 2007), as well as an expectation of greater interannual variability (Easterling et al. 2000). Ecologists are charged with identifying biotic communities and ecosystems most at risk for declines… Read more »
Working Group Goals: Given that this is the first attempt to address the issue of network availability of vegetation data our goals are extremely fundamental but critical at this stage: Assess the willingness of sites to participate in a Veg-DB system. Given the complexity of these databases, participating in this system will require a significant… Read more »
Woody encroachment is occurring worldwide (Archer 1995), with negative effects on biodiversity in North America (Ratajczak et al. in press) and uncertain effects on ecosystem functioning (Barger et al. 2011). The spatial properties of tree and grass dominance are well-studied and strongly suggest that woody encroachment of grasslands represents a shift to an alternative stable… Read more »
Zoning, building codes, subdivision ordinances, and neighborhood association rules are the most pervasive institutions affecting land use in the USA, yet their impact on land use change and ecosystem services and the distribution of these environmental goods and “bads” is highly variable and not well understood[1]. The purpose of this working group is to coordinate… Read more »
BACKGROUND Monitoring nutrients in precipitation inputs and other ecosystem fluxes has advanced our understanding of biogeochemical cycling. However, uncertainty due to variability or error in observations and models has rarely been reported in ecosystem studies. This makes it difficult to determine rates of change over time or compare results across multiple sites with quantitative confidence. … Read more »
Rationale: While the importance of legacy effect characterization to interpreting long-term records of ecological conditions has continued to emerge (Bain et al. in review “Legacies in Material Flux: Structural Catchment Changes Pre-date Long-term Studies” BioScience) some early structural legacies (e.g. substantial soil losses to erosion) are challenging to characterize with controlled experiments. However, the extended… Read more »
