1. Epiphytes have the potential to modify the canopy environments in which they grow. Accurately evaluating the impact of epiphytes can be challenging, since plants without epiphytes may also otherwise differ from host plants, and experimental removal is impractical and difficult to replicate in many forests. 2. We studied the impacts of epiphytes (primarily fruticose lichens and Tillandsia spp.) on host plants (Eulychnia saint-pieana and Caesalpinia spinosa) in two fog ecosystems in Chile (Pan de Azucar) and Peru (Atiquipa). These desert ecosystems sustain very high epiphyte loads and depend heavily on fog-water inputs. Using a combination of artificial substrates and epiphyte removals we show significant impacts of epiphytes on their host plants. 3. The presence of epiphytes reduced throughfall volumes, reducing fog and rainfall inputs to the soil beneath host plant canopies. 4. Soil moisture loss rate was increased below cacti after removal of epiphytes from sun-facing but not shade-facing branches. This suggests epiphyte effects on hosts are microclimatic. 5. Epiphytes also buffered temperature fluctuations and reduced daytime vapour pressure deficit (VPD). 6. Epiphytes can have strong effects on host plant ecophysiology and forest ecosystem processes, making them an important component for models and studies of canopy environments.
Soil Moisture Datalogger records
This database contains data from soil moisture sensors, soil temperature sensors and raingauges near the summit of Cerro Lloque, Comuna Campesina de las lomas de Atiquipa y Taimara, Provincia de Caravelí, Región de Arequipa, Perú. Further detail is contained in the ReadMe file.
SoilMoistureLogging.csv
Handheld Soil moisture below Caesalpinia spinosa trees
This data file (AtiquipaCS620soilmoisture.csv) contains data on spatial patterns of volumetric soil moisture recorded below Caesalpinia spinosa trees on Cerro Lloque, Comuna Campesina de las lomas de Atiquipa y Taimara, Provincia de Caravelí, Región de Arequipa, Perú. All data was recorded using a CS620 handheld TDR soil moisture probe (Cambell Scientfic Inc., Utah, USA). Soilmoisture readings were taken at varying distances from the base of trees (0 to 500cm in 50cm intervals) with 5 replicate measurements at each distance, for transects extending in each cardinal driection from the base of trees. Of this data, only that from a distance of 150cm from the base (below the canopy but unaffected by stemflow) of experimental tree pairs (1 and 2), pooled for all cardinal directions, was used in Stanton, Huallpa et al. 2014. For more any additional information about the data or the study please contact Dr. Daniel Stanton (stan0477@umn.edu). The columns are as follows: Date: Date of sampling as Year-month-day. Number: Number of the experimental tree (1 through 7). Direction: Cardinal direction from tree base of sampling transect (E-East, S-South, W-West, N-North). Distance: Distance in cm from base of tree of sampling location. Soilmoisture: Volumetric soil moisture (%)
AtiquipaCS620soilmoisture.csv
GravimetricSoilMoisturePandeAzucar
This dataset contains soil masses (wet and dry) below Eulychnia saint-pieana cacti following rainfall in the Lomitas sector, Pan de Azucar National Park, Region de Atacama, Chile. Soil samples were taken from the surface or at a depth of 5cm during the week following a once in a decade rainfall event on May 16th 2010. Samples were taken from open ground or from below cacti with epiphytes untouched (control), epiphytes removed from the south facing side or epiphytes removed from the north-facing half. Cacti for each treatment were chosen to be of comparable size and exposure to fog. For more any additional information about the data or the study please contact Dr. Daniel Stanton (stan0477@umn.edu).
Epiphyte_Microclimate
This spreadsheet (Epiphyte_Microclimate.csv) contains microclimate measurements recorded by iButtons (Embedded Datasystems, Texas, USA) on the surface of plants with or without epiphytes. Data was collected in 2009 and 2010 at both the Comuna Campesina de las lomas de Atiquipa y Taimara, Arequipa, Perú and the Parque Nacional Pan de Azúcar, Región de Atacama, Chile. All dataloggers were paired (with and without epiphytes) and attached to the surface of the host plant. For any additional information about the data or the study please contact Dr. Daniel Stanton (stan0477@umn.edu). Column headers are described in the ReadMe file.