mazzini, flavia; relva, m.a. & malizia,...
TRANSCRIPT
Large mammalian herbivores play important roles as drivers of
communities and ecosystems.
The impacts of herbivory on vegetation have been widely studied on grasslands, while
herbivory impacts on woody communities remain less explored.
Impacts in high net primaryproductivity forest is far less
understood
Mountain cloud forest (Yungas)< grazing
> Species turnover rate, increase biomass and basal area
Tropical Mature forest< grazing
Structural, functional and compositional changes
In Argentina the agronomic line is being push leaving livestock
in less favorable zone
Few data is available on cloud forests in Argentina. That lack of proportion of in is the same in Latin-American context and world wide
Cloud forest management and conservation due to ecosystems services is national high priority.
Silvo-Pastoral knowledge in Argentina regions
(Peri et al 2015)
Informationdisequilibrium
Transhumance is a commonpractice in the communities
Livestock is the main livelihood of rural communities.
Introducción
Mountain cloud forest has a structural complexity that makes it worth to study the interaction between livestock and forest.
So, livestock is consider as a disturbance agent able to alter cloud forest regeneration.
Cattle have stablished hundreds of years ago, it has been introduced during Latin America Spanish conquest. Imposing a new herbivore
regimen in the area.
Introducción
We hope that animal use variables have some influence in saplings abundance and underwood structure.
Studied the impact on the abundance and size of regeneration of the main forestry species under a variety of different
browsing regimes
Physical attributes of sites, vegetation and animal use variables are being evaluated
Physical attributes of sites, vegetation and animal use variables are being evaluated
Site/PlotSaplings
abundanceCattle feces
Grazing
(0,1,2,3)
bhd.prom
(cm)
stant
structure
hight (m)
canopy
coverage l
(m)
saplings hight
(cm)
ABL 3.25 8.00 1.43 10.08 5.33 82.32 42.24
ABL1 2.50 12.00 1.69 8.16 5.00 83.79 24.63
ABL2 4.50 7.00 0.86 10.52 6.00 76.45 52.52
ABL3 2.75 5.00 1.75 11.56 5.00 86.71 49.58
BOT 1.75 1.00 0.46 19.88 9.67 72.08 57.33
BOT1 1.00 0.00 0.50 13.63 7.00 62.30 83.75
BOT2 3.25 3.00 0.63 21.52 10.00 67.03 60.73
BOT3 1.00 0.00 0.25 24.50 12.00 86.91 27.50
CCH 3.08 4.00 1.03 13.78 12.67 84.32 37.54
CCH1 4.75 2.00 1.16 16.28 15.00 78.03 41.75
CCH2 2.25 2.00 0.88 17.75 15.00 89.05 33.13
CCH3 2.25 8.00 1.05 7.29 8.00 85.88 37.75
CLG 2.75 0.00 0.04 12.84 10.00 75.68 62.96
CLG1 3.50 0.00 0.08 8.51 7.00 75.78 84.88
CLG2 3.50 0.00 0.03 10.54 12.00 79.40 88.75
CLG3 1.25 0.00 0.00 19.47 11.00 71.85 15.25
CLR 2.25 0.33 0.39 16.78 11.33 80.85 54.18
CLR1 1.75 0.00 0.00 15.77 10.00 87.74 63.33
CLR2 1.75 1.00 0.13 17.29 12.00 81.95 44.63
CLR3 3.25 0.00 1.04 17.30 12.00 72.87 54.58
ESC 3.42 2.00 0.68 10.29 3.50 74.36 55.91
ESC1 1.75 3.00 0.94 7.24 3.50 74.56 32.19
ESC2 1.25 1.00 0.50 14.20 4.00 74.06 71.75
ESC3 7.25 2.00 0.61 9.44 3.00 74.46 63.79
ResultsResults General Table
First 6 sites
General descriptive
Results
Total tree:66 Species34 Families
Forestry :8 species5 Families
ResultsPrincipal Component analysis
Animal use and stand structure selected variables
Important variables in the spatial arragement of sites are: (+) grazing and feces (-) hight and bhd.prom (Coord 1) and coverage
and sapling (Cood 2)
Initial Model: AIC=656
Results
feces grazingcanopy
coverage
canopy
hightbhd.prom
feces x
c.hight
c.cov x
grazingdif logLik AICc delta weigth
-9.777 3.996 0.1504 6 -241.687 496.60 0.00 0.377
-1.024 3.736 0.1824 0.1382 7 -241.307 498.30 1.68 0.163
-0.8278 4.347 5 -243.931 498.70 2.12 0.131
-0.9755 4.013 0.1511 0.00591 7 -241.683 499.00 2.43 0.112
-0.9782 3.995 0.1505 -0.001285 7 -241.687 499.00 2.44 0.112
-1.2460 3.507 0.1509 -0.07582 -0.142 8 -240.490 499.20 2.55 0.105
GLM Model
Final Model: Sapling.ab~N(µi, σ
2)µi=β0j(i)+ β1 grazingi + β2 fecesi
+ β3 canopy coveragei
β0j(i)~N(µj, σ2
sitio)
i:1,2,3 (plots)J:1,2,....25 (sitios)
Variables relative importance
Saplings abundance are being affected by cattle.
ConclusiónCONCLUSIONS
To Future: identify susceptible and resistant species in the grazing gradient.
Livestock is affecting underwood regeneration, thus forest structure and dynamics.
Animal variables are the most important when analyzing saplings abundance. Besides canopy coverage
This kind surveys is crucial to understand the importance of cattle role in mountain cloud forest structure and dynamics.
Variables CP 1 CP 2 CP 3 dap prom -0.65 -0.12 0.59bosteo 0.77 -0.32 0.30dosel -0.59 0.47 0.48cob 0.43 0.75 0.29ab juv 0.18 0.78 -0.33ramoneo 0.69 -0.03 0.54
Lambda Valor Proporción Prop Acum1 2.05 0.34 0.342 1.52 0.25 0.593 1.15 0.19 0.794 0.70 0.12 0.905 0.33 0.05 0.966 0.25 0.04 1.00
Autovalores Correlación con las variables originales