1. A1 Effects of nutrient manipulation (NUMEX) on the performance of tree species and the suitability of tree species as indicators for changing ecosystem properties Jürgen Homeier Plant Ecology, University of Göttingen Counterpart: Carlos Iván Espinosa, UTPL Loja

2. WP1: Long-term effects of nutrient addition on tree growth and carbon allocation (NUMEX plots,1000–3000m asl) Methods  Monitoring of aboveground key parameters is continued: - Fine litter production and quality - Leaf parameters (foliar nutrients) - Stem growth (dendrometer tapes)  Focus on the belowground compartment: (PhD thesis Jhenny Salgado, started 10/2013) - Fine root biomass - Fine root production (ingrowth cores/rhizoscopes) - Coarse root growth (2 tree species per Numex site) +N+P ?

3. WP2: Effects of continued nutrient addition on tree species composition (NUMEX plots,1000–3000m asl) Methods  Monitoring of tree recruitment (ongoing PhD thesis Daisy Cárate, DAAD) - Annual census of tree seedlings in Numex plots  Seedling experiments (PhD thesis Daisy) - Planting of seedlings of locally common tree species into the Numex plots and other forest sites:  one ongoing experiment with Heliocarpus, Cedrela & Podocarpus planted in May 2013 (San Francisco) to be harvested this year  one new experiment with Prunus starting this year at Numex 2000m

4. WP3: Identification of nutrient-sensitive tree species Methods  Extension of the existing trait database with leaf traits (e.g. leaf toughness, foliar nutrient concentrations) and stem traits (e.g. bark thickness, WSG, vessel density, vessel diameter, etc.)  Additional leaf samples of 300 trees and wood samples of 320 trees have already been collected Trichilia septentrionalis (Meliaceae) Alchornea lojaensis (Euph.)

5. TRENCH Tree-Ring Environmental Network for Climate Change Monitoring - Developing a tree-based indicator system for environmental change impacts on forest ecosystems in southern Ecuador Achim Bräuning Institute of Geography FAU Erlangen - Nuremberg

6. TRENCH  A2 Quantitative Erfassung holzanatomischer Parameter 6

7. TRENCH  A2 Quantitative Erfassung holzanatomischer Parameter  Neue Methode: Micr-CT (3-dimensionale Analyse) 7

8. TRENCH  A2 Laipuna: Erstellung von Jahrringchronologien und deren klimatische Interpretation Beispiel: Bursera graveolens 8 EL NIÑO

9. TRENCH  A2 Laipuna: Erstellung von Jahrringchronologien und deren klimatische Interpretation Beispiel: Bursera graveolens 9 DRY SEASON (JUN-DEC) RAIN SEASON (JAN-MAY)

10. TRENCH  A2 Laipuna: Erstellung von Isotopenreihen und deren klimatische Interpretation Beispiel: Bursera graveolens

11. TRENCH  A2 Planung  März/April 2014: Installation neuer Dendrometerstationen in Laipuna/RBSF  Laipuna: Wasserproben im Niederschlag/Boden/Xylem für 18O-Isotopie  Sommer/Herbst: Etablierung von Dendrometerstationen in El Cajas (Polylepis / Pinus)

12. Soil related projects in NUMEX-X  A7 The fate of phosphorus in forest and treeline ecosystems in Ecuador – Yvonne Oelmann  Nachanträge: DFG Bundle „N cycling“  A3 The soil animal community as indicator of changes in the structure and functioning of Andean ecosystems with altitude and nutrient input – Stefan Scheu  A4 Responses of arbuscular mycorrhizal fungi to nutrient additions in Southern Ecuador – Matthias Rillig  (Ax Response of element cycles in a tropical mountain rain forest to environmental and land-use change - Wolfgang Wilcke) 12

13. A7 – Yvonne Oelmann Research questions  Does the relationship between the mechanisms (biological versus geochemical control) underlying P retention in the Ecuadorian montane rainforest change with altitude?  Does N and P fertilization modify the relationship between the biological and the geochemical control? 13

14. A7 – Yvonne Oelmann Preliminary results  The P-saturation index in mineral soil increases with increasing altitude. Explaining variables (e.g. pH, mineralisation) yet to be measured 14

15. A7 – Yvonne Oelmann Preliminary results  The P-saturation index in mineral soil is higher if P is added  Fertilization effects even visible in the mineral soil below the thick organic layer  Geochemical control needs to be considered 15

16. A7 – Yvonne Oelmann Future work  Tübingen  geochemical control, baseline P storage & availability  Ecuador  sampling campaign in 2014 after symposium  analysis of enzyme activity (phosphatase)  Göttingen:  analysis of gross mineralisation (33P approach) 16

17. A3 – Stefan Scheu Bachelor and Master Thesis (2011 – 2013)  Master Thesis: Kristina Richter (Nov. 2013): Effects of nutrient addition (N, P, Ca) on soil arthropods along an altitudinal gradient of tropical montane rainforests in southern Ecuador  Master Thesis: Stephan Töppich (Nov. 2013): Soil microarthropod colonization of root and leaf litter and their effect on decomposition processes in a tropical mountain rain forest in Southern Ecuador 17

18. A3 – Stefan Scheu Publications 2013 18  Krashevska V, Sandmann D, Maraun M, Scheu S (2012) Consequences of exclusion of precipitation on microorganisms and microbial consumers in montane tropical rainforests. Oecologia, 170, 1067-1076.  Krashevska V, Sandmann D, Maraun M, Scheu S (2013) Moderate changes in nutrient input alter tropical microbial and protist communities and belowground linkages. Isme Journal.

19. A3 – Stefan Scheu Future Work  Long-term responses in NUMEX-X – sampling starting in summer 2014  15N labeling experiment: execution questionable without Wilcke  Rotated core experiment (cooperation with Rillig, Wilcke?)  Phylogeography of selected oribatid mites and testate amoebae – sampling starting in summer 2014 19

20. A4 - Matthias Rillig Thesis  Antje Gensing (Nov 2013): Responses of arbuscular mycorrhizal fungi to nutrient additions in a pot experiment conducted in Southern Ecuador Publications  Camenzind T, Rillig MC (2013) Extraradical arbuscular mycorrhizal fungal hyphae in an organic tropical montane forest soil. Soil Biology & Biochemistry, 64, 96-102  Camenzind T, Hempel S, Homeier J, Horn S, Velescu A, Wilcke W, Rillig MC: Nitrogen and phosphorus additions impact arbuscular mycorrhizal abundance and molecular diversity in a tropical montane forest. - resubmitted 20

21. A4 - Matthias Rillig Ongoing work  Until July 2014 - final analyses of 5 year effects in NUMEX  Final publication of overall fertilization effects on AMF and roots - in cooperation with Homeier/Hertel Future Work  Long-term responses in NUMEX-X - AMF abundance and molecular diversity - coordinated sampling  15N labelling experiment - questionable without Wilcke  Rotated core array - in cooperation with Scheu 21

22. (Wolfgang Wilcke) Publications  Wullaert H, Bigalke M, Homeier J, Cumbicus N, Valarezo C, Wilcke W (2013) Short-term response of the Ca cycle of a montane forest in Ecuador to low experimental CaCl2 additions. Journal of Plant Nutrition and Soil Science, 176, 892-903  Wilcke W, Leimer S, Peters T et al. (2013) The nitrogen cycle of tropical montane forest in Ecuador turns inorganic under environmental change. Global Biogeochemical Cycles, 27, 1194- 1204 Ongoing work  Ongoing PhD thesis of Andre Velescu - close to finish 5 year analyses in NUMEX; preparation to measure effects of 15N tracer experiment in 3-4 months 22