Abstract
Lakes and their topological distribution across Earth's surface impose ecological andevolutionary constraints on aquatic metacommunities. In this study, we group similarlake ecosystems as metacommunity units influencing diatom community structure.We assembled a database of 195 lakes from the tropical Andes and adjacent lowlands(8°N-30°S and 58-79°W) with associated environmental predictors to examine diatom metacommunity patterns at two different levels: taxon and functional (deconstructed species matrix by ecological guilds). We also derived spatial variables thatinherently assessed the relative role of dispersal. Using complementary multivariatestatistical techniques (principal component analysis, cluster analysis, nonmetric multidimensional scaling, Procrustes, variance partitioning), we examined diatom-environment relationships among different lake habitats (sediment surface, periphyton,and plankton) and partitioned community variation to evaluate the influence ofniche-and dispersal-based assembly processes in diatom metacommunity structureacross lake clusters. The results showed a significant association between geographicclusters of lakes based on gradients of climate and landscape configuration and diatom assemblages. Six lake clusters distributed along a latitudinal gradient were identified as functional metacommunity units for diatom communities. Variancepartitioning revealed that dispersal mechanisms were a major contributor to diatommetacommunity structure, but in a highly context-dependent fashion across lakeclusters. In the Andean Altiplano and adjacent lowlands of Bolivia, diatom metacommunities are niche assembled but constrained by either dispersal limitation or masseffects, resulting from area, environmental heterogeneity, and ecological guild relationships. Topographic heterogeneity played an important role in structuring plankticdiatom metacommunities. We emphasize the value of a guild-based metacommunitymodel linked to dispersal for elucidating mechanisms underlying latitudinal gradientsin distribution. Our findings reveal the importance of shifts in ecological driversacross climatic and physiographically distinct lake clusters, providing a basis for comparison of broad-scale community gradients in lake-rich regions elsewhere. This may help guide future research to explore evolutionary constraints on the rich Neotropicalbenthic diatom species pool.
| Original language | English |
|---|---|
| Pages (from-to) | 7865-7878 |
| Number of pages | 14 |
| Journal | Ecology and Evolution |
| Volume | 8 |
| Issue number | 16 |
| DOIs | |
| State | Published - 2018 |
Bibliographical note
Publisher Copyright:© 2018 The Authors.
Funding
The authors are grateful to colleagues who provided samples and published and unpublished diatom and associated environmental data for assembling the database: P. Tapia, N. Michelutti, W. Gosling, F. Mayle, B. Valencia, and J.P. Bradbury. Funded by NSF EAR-1338694, NSF-EAR1251678, NASA 15-BIODIV15-0013, and National Geographic #8672-09 grants to SF. The Colombia diatom database collection was funded from NWO-WOTRO grant WB 75368 to H. Hooghiemstra and MV, and Inter-American Institute for Global Change (IAI grant No. CRN3038)-NSF (grant GEO-1128040) to MV. Lowland sampling in Brazil, Argentina and parts of Bolivia was funded by National Geographic #9797-15 and NSF EAR 1541247 to MM. Ecuador sampling was supported by NSF Grants BSR-8021539 and BSR-8202658 to Paul Colinvaux and MSK. MSK thanks Michael C. Miller, Mark Nienaber and many NKU undergraduates who helped put the Ecuador diatom database together. The authors acknowledge Funded by NSF EAR-1338694, NSF- EAR1251678, NASA 15-BIODIV15-0013, and National Geographic #8672-09 grants to SF. The Colombia diatom database collection was funded from NWO-WOTRO grant WB 75368 to H. Hooghiemstra and MV, and Inter-American Institute for Global Change (IAI grant No. CRN3038)-NSF (grant GEO-1128040) to MV. Lowland sampling in Brazil, Argentina and parts of Bolivia was funded by National Geographic #9797-15 and NSF EAR 1541247 to MM. Ecuador sampling was supported by NSF Grants BSR-8021539 and BSR-8202658 to Paul Colinvaux and MSK. MSK thanks Michael C. Miller, Mark Nienaber and many NKU undergraduates who helped put the Ecuador diatom database together.
| Funders | Funder number |
|---|---|
| NWO-WOTRO | WB 75368 |
| National Science Foundation Arctic Social Science Program | NASA 15-BIODIV15-0013, EAR1251678, EAR-1338694, 8672-09 |
| National Science Foundation Arctic Social Science Program | |
| International Association for Identification | BSR-8202658, BSR-8021539, EAR 1541247, 9797-15 |
| International Association for Identification | |
| Inter-American Institute for Global Change Research |
Keywords
- Diatom guilds
- Lakes
- Latitudinal gradient
- Metacommunity
- Topographic heterogeneity
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Ecology
- Nature and Landscape Conservation