Pontificia Universidad Católica del Ecuador (PUCE) by vow16147

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									                  Pontificia Universidad Católica del Ecuador (PUCE)
                  Escuela de Ciencias Biológicas                  Av. 12 de Octubre 1076 y Roca
                                                                     Apartado postal 17-01-2184
                                                                         Fax: (593 + 2) 2991687
                                                                        Telf.: (593 + 2) 2991685
                                                                                 Quito - Ecuador




                           FINAL REPORT
             of a MAB-UNESCO Young Scientist Research Award
                                   Original project title
   Lianas (woody vines) as major agents of water and nutrient movement in tropical forest
            ecosystems: biological mechanisms and implications to conservation

                                        New project title
    Initial ecological studies of lianas in the 50-ha Yasuní Forest Dynamics Plot (YFDP),
                                       Amazonian Ecuador


Principal investigator: Hugo Romero-Saltos, M. Sc., Escuela de Ciencias Biológicas, PUCE

Today’s date: December 17, 2007

Total cost of the project: $30,000

Amount awarded by MAB-UNESCO: $5,000


The principal investigator is most indebted to the following people:

Collaborators:
Stefan Schnitzer, Ph.D., Professor, University of Wisconsin-Milwaukee, USA
Leonel Sternberg, Ph.D., Professor, University of Miami, USA
Robyn Burnham, Professor, University of Michigan, USA
Renato Valencia, Ph.D., Professor and Director of Yasuní Forest Dynamics Plot, PUCE, Ecuador

Undergraduate thesis student supported by this grant:
Nataly Charpantier, PUCE

Professional assistants:
Esteban Gortaire, Carolina Altamirano, Carlos Padilla

Other assistants:
Indigenous people from the local community (around 10 people employed, 1-2 at a time)
Hugo Romero-Saltos      December 2007        Final Report of a MAB-UNESCO Young Scientist Research Award



BACKGROUND

        In compliance with letter of agreement No. 2019.6 (REF. SC/EES/565/19, 2006,
BUDGET CODE: 32121303), I hereby present the final report of the research project on
liana ecology being conducted in the permanent Yasuní Forest Dynamics Plot (YFDP) in
Yasuní National Park, an UNESCO Biosphere Reserve in Amazonian Ecuador. The YFDP
has an area of 50-ha (500x1000 m) where all trees with diameter ≥1 cm (approximately
300,000 trees) have been censused several times since 1994 (the year the plot was
established). The YFDP is part of a worldwide network of plots designed to understand the
long-term demography of thousands of plant species and individuals, and how they will
respond to climate change (see www.ctfs.si.edu). Thanks to international funding, including
MAB-UNESCO funds, a sample of lianas now forms part of the long-term vegetation
monitoring program in the YFDP.

         Because of logistic and financial limitations, few months after the project started
(November 2005), the original research objectives stated in the UNESCO-MAB proposal
(April 2005) changed significantly. Specifically, the research activities to assess the role
lianas play on the ecosystem-level movement of water and nutrients were discarded because
we realized it was a complex research program requiring a lot more extra funding and
personnel. For instance, transpiration (sap flow) and photosynthesis measurements required
expensive instrumentation (approximately $30,000 of investment) that we were not able to
fund (and still can´t). We focused instead on collecting other kinds of data that, in the long
term, will still be very valuable to understand the ecological effects that lianas—the second
most dominant growth form in lowland tropical rainforests—have on the ecosystem. Such
data will allow to: (1) describe changes on diversity, abundance and biomass of lianas, (2)
understand their community dynamics (demography), (3) evaluate the competition effects of
lianas on the fitness of their host trees, and (4) understand the ecological and evolutionary
processes that maintain the high diversity of liana species in such a small area of forest.
These topics are relevant because, according to recently published studies, lianas in mature
Neotropical rainforests are becoming increasingly dominant and so may affect forest
dynamics at large. Indeed, lianas are important in gap regeneration processes and sometimes
can compete efficiently for resources with their host trees, causing them negative effects on
fertility and water relations, among others. The reasons for the notorious increase in liana
dominance are unknown, but considering the typical physiological adaptations of several
liana species (e.g., efficient CO2 use during photosynthesis under high solar radiation up in
the forest canopy), they could be actively responding to changing weather conditions, i.e.
lianas could be considered good biological indicators of climate change.

        The total cost of this project was $30000. Most of the funding ($18000) came through
a grant from the Center for Tropical Forest Science (Smithsonian Tropical Research
Institute), while the remainder was funded by the MAB-UNESCO Young Scientist Research
Award and by a Tropical Biology Fellowship from the University of Miami.

RESEARCH TOPICS, METHODS AND RESULTS

       In this section I summarize the research topics, the methodology followed and the
results obtained. Data analyses are currently underway. The project activities took
approximately 1.5 years of field and lab work, since November 2005. Days in the field
summed up to 120 days, for a team of three to four people.



                                                                                           pg. 2 of 9
Hugo Romero-Saltos       December 2007        Final Report of a MAB-UNESCO Young Scientist Research Award



1. Diversity and community structure

        To broadly assess the diversity and structure of the liana community in the plot, we
decided to survey the lianas in a 20x500 m area and in 20 subplots (20x20 m each) evenly
scattered (regular grid) throughout the first 25 ha and covering all kinds of habitat (Figure 1).
Because of the convoluted growth pattern of many lianas, the point of diameter measurement
(PDM) at the main stem was located following a published standardized methodology.
Further, in order to detect in future censuses those liana individuals originating from
vegetative reproduction (ramets), we have measured and tagged all main stolons and visible
branches (i.e., height ≤2 m, diameter ≥1 cm). The main stem and ramifications of each liana
were permanently labeled with aluminum tags coded with a unique identifying number.

        When we could not fully identify a liana in the field (i.e., give it a species name:
Genus + epithet), we collected a botanical sample and preserved it following standard
procedures (pressing, drying). In total, we collected near 1,400 botanical specimens (plus
their respective duplicates) which were initially identified at the Herbarium of the Pontificia
Universidad Católica del Ecuador (QCA) and at Ecuador's National Herbarium (QCNE).
Further identifications were made by Dr. Robyn Burnham, a collaborator, during this year
(May–August 2007) when she worked at the renowned Missouri Botanical Garden (MO) and
University of Michigan (MICH) herbaria, in the United States. Another liana expert, Dr.
Lúcia Lohmann from Brazil, specialist of the plant family Bignoniaceae, will also send more
taxonomical identifications by the end of this year.

        In the 1.8 ha sampled, we found 2,649 liana individuals. A liana individual may
include several climbing stems separated by several meters (sometimes >10 m) that may
seem independent, but in reality are connected underground. The 2,649 individuals are
currently classified in 41 families, 104 genera and 236 (morpho-)species (78% fully
identified to species). We estimate there are around 300 liana species in the whole 50-ha plot,
half of what is estimated for the Yasuní area (1.5 million ha).

        The preliminary data generated in this part of the project have been used in two ways:
(1) in April 2006, a preliminary dataset from the 20x500 m area was shared with an
international working group on liana ecology that met at the National Center for Ecological
Analysis and Synthesis (University of California-Santa Barbara, USA) mainly to compile and
organize a global dataset of liana inventories; and (2) in November 2006, basic analyses on
diversity and community structure were presented by Nataly Charpantier—the Ecuadorian
student whose thesis of “Licenciatura” (equivalent to a B.S. degree) was supported by this
grant—as a talk (see Appendix) at the Annual Meeting of the Biological Society of Ecuador
(“XXX Jornadas Nacionales de Biología”). In addition, the abundance data will be used in
the future by Dr. Stefan Schnitzer—the main collaborator and who visited Ecuador at the
beginning of the project in November 2005—in an analysis at a larger geographical scale
(plots from Asia and the Neotropics) to test whether edaphic factors (mainly nutrient
distribution) can explain liana abundance patterns.

2. Competition effect of lianas on trees

         To evaluate a possible effect on growth rates of trees because of competition by
surrounding lianas, for every liana in the 20x500 m area (column 7), we mapped its main
(i.e., diameter ≥1 cm) rooting points, stolons, and branches reachable from ground level
(height ≤2 m). Figure 2 shows an example of this mapping for a 10x10 m quadrat. The


                                                                                            pg. 3 of 9
Hugo Romero-Saltos      December 2007        Final Report of a MAB-UNESCO Young Scientist Research Award



diameter of each main branch 5 cm just above the branching point was also recorded. Further,
for every large liana (i.e., diameter ≥2.5 cm), we recorded the tree hosting most of the liana
leaves, and the distance between the main rooting point of the liana and the tree trunk. The
rooting points of the lianas have been digitalized using ArcView (Figure 3).

3. Functional traits of lianas

        Data on functional traits can be applied to studies about community assemblage (how
the plant community originated and is maintained) and are also important proxies of different
ecophysiological processes such as photosynthesis efficiency, water/nutrient status, among
others. To sample functional traits of as many species of lianas as possible, we organized
three field trips in September 2006, December 2006, and June 2007. Leaf functional traits
(specific leaf area, leaf size, leaf thickness, N, P and C content, and 15N and 13C isotopic
signatures) were measured for 181 liana species. We further measured wood specific gravity
from around 100 liana species. The methodology to quantify functional traits followed
standard protocols. The nutrient content and isotopic signature analyses were conducted at
the Stable Isotope Laboratory at the University of Miami during March 2007 and August–
October 2007 (collaboration with Dr. Leonel Sternberg).

FUTURE PLANS

        With a new grant from CTFS recently awarded to the principal investigator, we will
complete the collection of the main functional traits, recensus the 20x500 m area, and extend
our survey to the second 25 ha of the 50-ha plot following the same methodology applied in
the first 25 ha, i.e. surveying the lianas in the 20x20 m quadrat located in the center of each
square ha. The final result will be 50 20x20 m quadrats (one per ha) arranged as a regular
grid, for a total of 2.8 ha sampled (including the continuous 20x500 m area). With this
stronger dataset, we will prepare publications on the community structure and diversity of
lianas in the plot, their habitat preferences, their demographic dynamics, the community
assemblage processes influencing the liana community at different spatial scales, and a
metadata paper showing the raw functional trait values of each species. Other potential
publications will depend on the insights that the exploratory analyses can give, such as the
potential effect of liana competition on growth rates of trees. We hope the resulting
publications help to make a good case when looking for the enormous funding needed to
census all the lianas in the 50-ha plot, which are conservatively estimated in 70,000
individuals. Only such long-term monitoring program of a large plant community can give us
confident answers as to how tropical rainforest ecosystems may change as a result of global
climate change.


This concludes the final report. Please feel free contacting me (hgromero@puce.edu.ec or
hugo.romero@bio.miami.edu) if you have any question.

                                          Sincerely,




                                 Hugo Romero-Saltos, M.Sc.



                                                                                           pg. 4 of 9
Hugo Romero-Saltos      December 2007        Final Report of a MAB-UNESCO Young Scientist Research Award




Figure 1. Location of the 20x20 m subplots (in red) where lianas have been sampled in the
first 25 ha of the 50-ha plot. The total area sampled was 1.8 ha. Every 20x20 m quadrat in the
plot has been assigned a topographically defined habitat.




                                                                                           pg. 5 of 9
Hugo Romero-Saltos      December 2007       Final Report of a MAB-UNESCO Young Scientist Research Award




Figure 2. Example of a map of rooting points (diameter ≥1 cm), stolons (diameter ≥1 cm),
and visible main branches (diameter ≥1 cm, height ≤2 m) as recorded in a field datasheet.
Filled circles represent original rooting points and open circles represent secondary rooting
points. A continuous line represents a creeping stem or stolon. A dashed line represents an
aerial stem. Branches are coded with a letter (A, B, C, etc.). A single point (e.g., 070179)
represents a liana that climbs directly to the canopy, with no creeping stems.




                                                                                          pg. 6 of 9
Hugo Romero-Saltos     December 2007        Final Report of a MAB-UNESCO Young Scientist Research Award




Figure 3. Example of the rooting points of lianas in a portion of the 20x500 m area, as seen
when digitalized using ArcView. Tag numbers are not shown. Filled circles represent original
rooting points and open circles represent secondary rooting points.



                                                                                          pg. 7 of 9
  Hugo Romero-Saltos                                   December 2007                      Final Report of a MAB-UNESCO Young Scientist Research Award



  Appendix
  Slide presentation in the XXX Jornadas Nacionales de Biología in Ecuador (November 2006)
  using preliminary data.

Slide 1                                                                                       Slide 2
             DIVERSIDAD Y ESTRUCTURA POBLACIONAL
              DE UNA COMUNIDAD DE LIANAS EN EL                                                              ¿Qué son las lianas?
                   PARQUE NACIONAL YASUNÍ
                                                                                                            • Plantas vasculares con semilla

                                                                                                            • Bejucos leñosos

                                Charpentier,      Romero-
                         Nataly Charpentier, Hugo Romero-Saltos,                                            • No son epífitas ni parásitas
                           Esteban Gortaire & Stefan Schnitzer
                                                                                                            • Siempre enraizadas en el suelo
                      Pontificia Universidad Católica del Ecuador, Herbario QCA
                   University of Miami, Department of Biology, Coral Gables, USA
                                                                      Gables,                               • Amplia ramificación
                           Wisconsin,                          Sciences, Milwaukee,
             University of Wisconsin, Department of Biological Sciences, Milwaukee, USA

                                               2006




Slide 3                       Mecanismos para trepar
                                                                                              Slide 4
                                                                                                               Usos                                                   Cucurbitaceae
                                                                    • espinos


                                                                    • tendriles

                                                                                                                                               Uña de gato
                                                                    • ramas laterales                                                          (Uncaria guianensis)
                                                                    envolventes
                                                                                                                                                                             Passiflora sp.

                                                                    • tallos volubles


                                                                    • ganchos
                                                                                                            Ayahuasca (Banisteriopsis caapi)

                                                                    • raíces
                                                                                                                                                                          Mucuna sp.
                                                                    adveniticias
                                                                                                                                                  Curare




Slide 5      Rol ecológico en el ecosistema
                                                                                              Slide 6
                                                                                                                  Distribución
             • Las lianas intervienen en la dinámica del bosque
                                                                                                                  • Presentes en todos los bosques del planeta

             • Importancia en el flujo de carbono
                                                                                                                  • Mayor diversidad y abundancia en bosques tropicales
              (fotosíntesis, respiración, producción hojarasca)

                                                                                                                  • Ciertas especies prefieren hábitats con mucha luz
             • Transpiración del bosque

                                                                                                                  • Parque Nacional Yasuní:
             • Alimento y refugio para animales                                                                         ~ 500 spp. de lianas
                                                                                                                        alta diversidad en bosques de tierra firme

             • Puentes de dosel




Slide 7                                                                                       Slide 8
                                      Área de estudio
                                                                                                                                                                              Colina
                                                                                                                                                                              Pendiente
                                                                                                                                                                              baja
                                                      •1   millón ha
                                                                                                                                                                              Pendiente
                                                                                                                                                                              pronunciada
                                                      • Bosque húmedo tropical
                                                                                                                                                                              Pendiente
                                                                                                                                                                              alta
                                                      • 3000 mm
                                                                                                                                                                              Valle
                                                      • 22oC - 34oC                                                                                                           Bosque
                                                                                                                                                                              secundario




                                                                                                                                                                                      pg. 8 of 9
   Hugo Romero-Saltos                            December 2007                 Final Report of a MAB-UNESCO Young Scientist Research Award



 Slide 9         FAMILIAS         INDIVIDUOS   GÉNEROS        ESPECIES
                                                                                 Slide 10
                   40               2659        103              239
                                                         (165 identificadas,
                                                         74 morfoespecies)

                 Fabaceae           319          8                10

                 Hippocrataceae     292          8                14

                 Sapindaceae        265          3                33

                 Bignoniaceae       208          15               23

                 Verbenaceae        175          1                1

                 Combretaceae       156          1                1

                 Malpighiaceae      135          9                22




Slide 11                                                                         Slide 12




Slide 13                                                                         Slide 14




Slide 15                                                                         Slide 16
                Género más diverso:

                Paullinia (26 spp.)




Slide 17                                                                         Slide 18          En resumen
                                                                                                   • Alta diversidad alfa de lianas: 239 spp. en 1,8 ha, casi el 50% del
                                                                                                   total de lianas estimadas para todo Yasuní.

                                                  Especie más abundante:                           • Las lianas son comunes en el bosque: 2659 ind. en 1,8 ha.

                                                                                                   • Un taxon determinado de lianas pueden ser dominante de
                                                  Machaerium cuspidatum                            diferentes maneras: por su área basal, por su frecuencia (no
                                                                                                   analizada) o por su abundancia.
                                                  (198 ind.)
                                                                                                   • Machaerium cuspidatum fue la liana más común en la parcela.

                                                                                                   •Combretum laxum fue la especie con individuos más grandes.

                                                                                                   • Este estudio complementará las investigaciones realizadas con
                                                                                                   árboles para entender la dinámica del Bosque Yasuní, y el
                                                                                                   funcionamiento del ecosistema.




                                                                                                                                                                  pg. 9 of 9

								
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