TY - JOUR
T1 - Estimating and interpreting migration of Amazonian forests using spatially implicit and semi-explicit neutral models
AU - Pos, Edwin
AU - Guevara Andino, Juan Ernesto
AU - Sabatier, Daniel
AU - Molino, Jean-François
AU - Pitman, Nigel
AU - Mogollón, Hugo
AU - Neill, David
AU - Cerón, Carlos
AU - Rivas-Torres, Gonzalo
AU - Di Fiore, Anthony
AU - Thomas, Raquel
AU - Tirado, Milton
AU - Young, Kenneth R
AU - Wang, Ophelia
AU - Sierra, Rodrigo
AU - García-Villacorta, Roosevelt
AU - Zagt, Roderick
AU - Palacios Cuenca, Walter
AU - Aulestia, Milton
AU - Ter Steege, Hans
PY - 2017/6
Y1 - 2017/6
N2 - With many sophisticated methods available for estimating migration, ecologists face the difficult decision of choosing for their specific line of work. Here we test and compare several methods, performing sanity and robustness tests, applying to large-scale data and discussing the results and interpretation. Five methods were selected to compare for their ability to estimate migration from spatially implicit and semi-explicit simulations based on three large-scale field datasets from South America (Guyana, Suriname, French Guiana and Ecuador). Space was incorporated semi-explicitly by a discrete probability mass function for local recruitment, migration from adjacent plots or from a metacommunity. Most methods were able to accurately estimate migration from spatially implicit simulations. For spatially semi-explicit simulations, estimation was shown to be the additive effect of migration from adjacent plots and the metacommunity. It was only accurate when migration from the metacommunity outweighed that of adjacent plots, discrimination, however, proved to be impossible. We show that migration should be considered more an approximation of the resemblance between communities and the summed regional species pool. Application of migration estimates to simulate field datasets did show reasonably good fits and indicated consistent differences between sets in comparison with earlier studies. We conclude that estimates of migration using these methods are more an approximation of the homogenization among local communities over time rather than a direct measurement of migration and hence have a direct relationship with beta diversity. As betadiversity is the result of many (non)-neutral processes, we have to admit that migration as estimated in a spatial explicit world encompasses not only direct migration but is an ecological aggregate of these processes. The parameter m of neutral models then appears more as an emerging property revealed by neutral theory instead of being an effective mechanistic parameter and spatially implicit models should be rejected as an approximation of forest dynamics.
AB - With many sophisticated methods available for estimating migration, ecologists face the difficult decision of choosing for their specific line of work. Here we test and compare several methods, performing sanity and robustness tests, applying to large-scale data and discussing the results and interpretation. Five methods were selected to compare for their ability to estimate migration from spatially implicit and semi-explicit simulations based on three large-scale field datasets from South America (Guyana, Suriname, French Guiana and Ecuador). Space was incorporated semi-explicitly by a discrete probability mass function for local recruitment, migration from adjacent plots or from a metacommunity. Most methods were able to accurately estimate migration from spatially implicit simulations. For spatially semi-explicit simulations, estimation was shown to be the additive effect of migration from adjacent plots and the metacommunity. It was only accurate when migration from the metacommunity outweighed that of adjacent plots, discrimination, however, proved to be impossible. We show that migration should be considered more an approximation of the resemblance between communities and the summed regional species pool. Application of migration estimates to simulate field datasets did show reasonably good fits and indicated consistent differences between sets in comparison with earlier studies. We conclude that estimates of migration using these methods are more an approximation of the homogenization among local communities over time rather than a direct measurement of migration and hence have a direct relationship with beta diversity. As betadiversity is the result of many (non)-neutral processes, we have to admit that migration as estimated in a spatial explicit world encompasses not only direct migration but is an ecological aggregate of these processes. The parameter m of neutral models then appears more as an emerging property revealed by neutral theory instead of being an effective mechanistic parameter and spatially implicit models should be rejected as an approximation of forest dynamics.
KW - betadiversity
KW - migration
KW - neutral theory
KW - parameter estimation
KW - species composition
KW - species diversity
U2 - 10.1002/ece3.2930
DO - 10.1002/ece3.2930
M3 - Article
C2 - 28649338
SN - 2045-7758
VL - 7
SP - 4254
EP - 4265
JO - Ecology and Evolution
JF - Ecology and Evolution
IS - 12
ER -