Nonlinearity is a salient feature in all complex systems, and it certainly characterizes biogeochemical cycles in ecosystems across a wide range of scales. Soil carbon emission is a major source of uncertainty in estimating the terrestrial carbon budget at the ecosystem level and above. Due to the lack of consideration of the nonlinearity in temperature sensitivity of soil respiration, several ...

The self-thinning rule relates plant mass to plant density in crowded, even-aged stands by a power-law equation with an exponent −3/2. The rule is widely accepted as an empirical generalization and quantitative rule that applies across the plant kingdom. It has been called the only law in plant ecology. But the evidence supporting it has recently come under critical scrutiny. The theoretical an...

Predicting impacts of climate change or alternative management on both food production and environment safety in agroecosystems is drawing great attention in the scientific community. Most of the existing agroecosystem models emphasize either crop growth or soil processes. This paper reports the latest development of an agroecosystem model (Crop-DNDC) by integrating detailed crop growth algorit...

The incorporation of Allee effects into a simple metapopulation extinction model reveals a large non-linear reduction in mean time to extinction with small changes in an Allee limit. The extent of this reduction is dependent on the level of migration in the metapopulation. With small amounts of migration, small changes in the Allee limit result in large changes in the mean time to extinction. W...

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Exergy is an effective, single measurement to express the information level of communities, while the trends of community dynamics are difficult to represent since communities consist of different species varying in a complex manner. Using the data concerning benthic macroinvertebrate communities collected from streams, we implemented artificial neural networks in patterning and predicting exer...

Ecosystem models which include both variability of driving variables as an input, and uncertainty and/or stability in their predictions are rare, especially outside of forest and cropland applications. Our objective is to investigate the stability of productivity levels and temporal patterns in a northern mixed grass prairie site using scenarios of varying levels of climate variability. Predict...

The application of ecological exergy as a suitable system-oriented development indicator of ecosystems and the estimation proposals from biomass are revised. DNA contents (C-values) of several groups of organisms are figured, either determined by flow cytometry or taken from literature. The applicability of DNA contents for determination of weighing factors to estimate ecological exergy from th...