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General model for N2O and N2 emissions from soils due to denitrification

General CH4 oxidation model and comparisons of CH4 oxidation in natural and managed systems

General models for trace gas flux from denitrification and methane oxidation in soils

Pollen flow in fragmented tropical tree populations

Estimated losses and storage of N inputs to 15 watersheds of the mid-Atlantic and New England states, USA

The Future of Bioinformatics in LTER

Recovery plan review

Spatial population dynamics: Analyzing patterns and processes of population synchrony

The search for mechanisms behind spatial population synchrony is currently a major issue in population ecology. Theoretical studies highlight how synchronizing mechanisms such as dispersal, regionally correlated climatic variables and mobile enemies might interact with local dynamics to produce different patterns of spatial covariance. Specialized statistical methods, applied to large-scale survey data, aid in testing the theoretical predictions with empirical estimates.

A new test for density-dependent survival: The case of coastal cod populations

A new test based on the generalized additive model is proposed to investigate density-dependent mortality in the juvenile cohorts of cod. Density dependence implies that the function linking the count of a cohort in one year to the count in the succeeding year is convex. The method estimates (without functional assumptions) the function linking the two counts and provides a level of significance for any convexity. We investigate the power and bias of the new test on the basis of simulated data.

Cycles and trends in cod populations

Year-to-year fluctuations in fish stocks are usually attributed to variability in recruitment, competition, predation, and changes in catchability. Trends in abundance, in contrast, are usually ascribed to human exploitation and large-scale environmental changes. In this study, we demonstrate, through statistical modeling of survey data (1921–1994) of cod from the Norwegian Skagerrak coast, that both short- and long-term variability may arise from the same set of age-structured interactions.