12.9.17

Plant production in seasonal wetlands



Plant primary production is a key driver of several ecosystem functions in seasonal marshes, such as water purification and secondary production by wildlife and domestic animals. Estimating the spatio-temporal dynamics of biomass production is however challenging in seasonal wetlands with variable flooding regimes.

In this paper, stemming from the MSc Thesis developed by Maria Lumbierres in out group, we develop a method to estimate standing aboveground plant biomass using NDVI Land Surface Phenology (LSP) derived from MODIS, and follow to calibrate and validate it in the Doñana National Park’s marsh vegetation. The estimator was robust to environmental variation in precipitation and hydroperiod, and to spatial variation in the productivity and composition of the plant community - and may represent a key tool for the long-term monitoring and management of seasonal marsh ecosystems.

Model predictions indicate that the marsh areas with highest productivity coincide with those in which productivity has been declining during the last 16 years—suggesting changes in flooding patterns and/or the potential effect of overgrazing by wild and domestic herbivores. Further work will hopefully allow us to disentangle these two proceses.

Lumbierres, M., Méndez, P. F., Bustamante, J., Soriguer, R., & Santamaría, L. (2017). Modeling biomass production in seasonal wetlands using MODIS NDVI land surface phenology. Remote Sensing 9: 392.

3.3.17

Migratory Birds as Global Dispersal Vectors

 

After many years of work in the elusive process of long-distance dispersal by migratory birds, we feel ready to make the huge leap that separates the phenomenological description of an essentially unpredictable process, to modeling and forecasting a challenging but predictable one.

Can we suceed? This paper synthesizes our view of the state of the art and our proposal for future research. We believe in its importance, and will be happy to hear your opinion.

Viana, D., Santamaría, L., Figuerola, J. (2016) Migratory birds as global dispersal vectors. Trends in Ecology and Evolution 31: 763-75.