Equipment & Data Collection Processes

Belowground Component

Belowground Component

Equipment and sampling procedures performed beneath the soil surface or in processes that occur in this environment. 

Aboveground Component

Equipment and sampling procedures of the processes that occur in the forest understory.

Plant Physiology Component 

Equipment used for the monitoring of plant functional processes along the entire forest structure.

Belowground Component 

 
Methane Analyzer - LI7814

LICOR 7814

LICOR 7814

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The LICOR 7814 is laser-based Trace Gas Analyzer that uses Optical Feedback-Cavity Enhanced Absorption Spectroscopy (OF-CEAS).

•Purpose: 

Soil CO2, CH4, and N2O measurements.

•Configuration:

Synchronized with the LI8100A and multiplexer

•Data:

Collected hourly

Processed through Soil Flux Pro

Minirhizotron

Minirhizotron tube inside the ground schematic view.

Iana Grullón-Penkova collecting high resolution images.

Sometimes very interesting things can be observed.

Minirhizotron tube inside the ground schematic view.

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The Minirhizotron system is a non-destructive monitoring system of the underground environment of roots.

•Purpose: 

Monitor roots through time in order to quantify root production, mortality, biomass, etc.

•Configuration:

2 (1 meter) tubes per plot

•Data:

Collected with a manual camera and iPod app Root Mobile
Every 2 weeks

Processed through Rootfly

Oxygen Sensors (Soil Pits)

Oxygen sensors during initial calibration in a humid environment.

Soil Pit above ground marking. Flags stand above sensors locations.

Oxygen sensors during initial calibration in a humid environment.

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One meter deep soil were excavated in order to sample and instrument the deep soil environment. Oxygen sensors were installed. 

•Purpose:

Quantify soil oxygen and potential sampling of other gases of the deep soil environment.

•Configuration: 

Sensors are installed at 3 different depths per soil pit. 

•Data: 

Collected through the CR1000 datalogger

Allows for point sampling of soil gases

Point Lysimeters

Pore water sampling instruments.

Intern Rosanise Odell collecting pore water samples.

Pore water sampling instruments.

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The Point Lysimeters are devices for measuring water percolation through the soil. 

•Purpose: 

 Collect pore water for quality and quantity assessments. 

•Configuration:

3 per plot at different depths (10, 30, 50 cm)

•Data:

Collected every 2 weeks

Resins 

Intern Pedro León prepares resins for their installation in our experimental plots.

Intern Pedro León prepares resins for their installation in our experimental plots.

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Resins act like roots in the ground, they interact with the soil, plants, and microbial community and exchange nutrients. •Purpose: 

Measure the concentrations of macro & micronutrients in soils. 

•Configuration:

3 resins per plot simultaneously (in 2 different cycles)

•Data:

Resin replacement and extraction: every 3 months

Managed by USGS collabs 

We extract the resins at Sabana and send them to Moab

Root & Soil Campaigns 

10 cm ingrowth core

Root specific respiration system, using a tabletop infrared gas analyzer.

Samples are ground using a ball-mill grinder.

10 cm ingrowth core

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Root and soil campaigns are complex process through which various elements are monitored.

•Purpose: 

Assess root biomass, respiration, biogeochemistry (BGC), microbial communities, and morphology of the first 10 cm of soil.

•Configuration:

Ingrowth cores are installed in multiple location in the plots.

•Parts:

Root and soil microbial samples

Root specific respiration measurements (table top infrared gas analyzer (IRGA))

Root sorting (dead or alive)

Root scanning (Epson scanner and WinRhizo software)

Soil BGC extractions

Root nutrient analysis

Soil Nutrient analysis

Soil Temperature and Relative Humidity Sensors 

Soil Moisture Meter

Soil Temperature Meters at 3 different depths.

CS655 soil temperature meters.

Soil Moisture Meter

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Continuos monitoring of the soil temperature and relative humidity is recorded with the help of sensors and a datalogger. 

 •Purpose: 

Quantify soil temperature and relative humidity

•Configuration:

Different depths and locations

CS655 Deep ( at 20-30 cm & 40-50 cm)

CS655 Surface (0-10 cm / 3 locations)

•Data:

Recorded by CR10000 datalogger
Continuous measurements (every 1 minute)

Soil Gas Flux 

Soil gas flux measurements are collected continuously using a multiplexed system and the LICOR 8100 and long-term chambers in our experimental plots. 

 •Purpose: 

Quantify the soil gas fluxes released to the atmosphere.

•Configuration:

LI 8100 + Multiplexer + Long-term chamber 

•Data:

Collected hourly

Processed through Soil Flux Pro

Aboveground Component 

 
Canopy Measurements

Densiometer

General Field Technician, William Mejía, taking canopy photos in the early hours of the morning.

General Field Technician, William Mejía, taking Leaf Area Index (LAI) measurements.

Densiometer

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We collect a series of canopy measurements to measure and contrast between solar radiation income and canopy geometry. The three methods we use are: canopy densiometer measurements, hemispherical photos, and leaf area index (LAI) measurements. 

•Purpose: 

Estimate canopy openness, plot light income, and leaf area index.

•Data:  

Collected monthly.

 

•Instruments:

Densiometer 

LI-2000

Camera + Fisheye lens

Coqui Surveys

Captured coqui stands on balance in the laboratory.

Former intern, Virginia-Rose Seagal, holds a coqui for measurements.

Captured coqui stands on balance in the laboratory.

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Coqui frogs are a very special symbol for Puerto Rico, and a key species in the Luquillo Forest. After the hurricanes a year long study was started.

•Purpose: 

Assess coqui movement and see how treatment affected this species population.

•Configuration: 

Frogs were captured in the plot's vicinity, taken to the lab for weighing, sizing, sexing, and marking; and then released.

•Data:  

Managed by collaborator Tanya Matlaga
Collected every 2 weeks over a year (2018-2019).

Litterfall

Litterfall basket in the field.

Litterfall basket being installed by one of our volunteers.

Litterfall baskets in the making.

Litterfall basket in the field.

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Litterfall is an important nutrient input to the forest floor, which we want to capture and characterize, for that we have installed baskets along out site.

•Purpose: 

Study litter input from the trees to the forest floor and assess its quantity (biomass) and quality (chemistry /nutrients).

•Configuration: 

20 baskets placed randomly along the site.

•Data:  

Collected every 2 weeks.

Samples should be ground

Sent to IITF lab for nutrient analysis

•Instruments:

PVC and wire mesh baskets (A = 0.44 x 0.44 m)

Microclimate Monitoring 

HOBO datalogger (for temperature and relative humidity) inside a protective shield and on an arm that extends from a peripheral post towards the center of the plot.

Bruce Kimball installing the understory weather station.

Former project manager, Aura Alonso, configuring the dataloggers.

HOBO datalogger (for temperature and relative humidity) inside a protective shield and on an arm that extends from a peripheral post towards the center of the plot.

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Weather stations allow us to monitor the microclimate of the forest understory. It enables researchers to discover seasonality, peaks, and trends in the climatic conditions of the very dynamic forest. 

•Purpose: 

1)Characterize the understory microclimate

2)Monitor the plot weather conditions

3)Assess the plots microclimate conditions vertical change related to vegetation dynamics post-hurricanes.

•Configuration: 

Understory weather station
Plot arm weather datalogger
vertical gradient HOBO Tower

•Data:  

-CR 1000 datalogger

-HOBO datalogger in the arm

-HOBO dataloggers in the PVC post

Plant Censuses

Tree tag on our field site, part of the tree census monitoring.

Luquillo-LTER volunteers performing our annual seedling census.

Former intern, Pedro León, during the 2019 tree census.

Tree tag on our field site, part of the tree census monitoring.

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Monitoring the vegetation gives us information about the ecological communities dynamics that happen in our site, both due to disturbance events like hurricanes, and due to our treatment.

•Purpose: 

Characterize site plant community distribution and structure.

•Configuration:  

Seedling censuses

Seedling herbivory photos

Seedling leaf traits

Tree census

Fern and herbaceous plants census

•Data:  

Collected yearly.

Fern and herbaceous data managed by David Matlaga.

Seedling herbivory data managed by Benedicte Bachelot.

Plant Height and Apparency 

General Field Technician, William Mejía, measuring plant height.

General Field Technician, William Mejía, measuring plant height.

General Field Technician, William Mejía, measuring plant height.

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Due to the lost of the forest structure because of the passage of Hurricanes Irma and Maria, these measurements were introduced to estimate the foliar volume inside the plots, and the plant height to adjust treatment accordingly.

•Purpose: 

Characterize plant structure inside the experimental plots.

•Configuration: 

Height: measure the highest part of the plant that is present at each of the 13 locations.

Apparency: 6 measurements at each height will be taken, two measurements at each of the three locations.

•Data:  

Collected monthly.

•Instruments:

PVC post and wood dowels.

Surface Lysimeters

Surface Lysimeter collection device.

Surface lysimeter.

surfacelysimeter3
surfacelysimeter3

General Field Technician, William Mejía, collecting surface lysimeter samples.

Surface Lysimeter collection device.

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A part of our routine sampling and in addition to our Point Lysimeters, we have installed a Surface Lysimeter to characterize the water that falls through the canopy and into our soil. •Purpose: 

Assess runoff water quality (chemistry).

•Configuration: 

1 lysimeter/ plot (downhill and in an angle)

•Data:  

Collected every 2 weeks.

Sent to collaborators at USGS for analysis.

Weekly Plot Photos

General Field Technician, William Mejia, collecting weekly plot photos.

General Field Technician, William Mejia, collecting weekly plot photos.

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This qualitative approach helps monitor the dynamics of the plots vegetation through visual estimates.

•Purpose: 

Monitor how the plots have changed over time as they are taken from approximately the same position

•Data:  

Collected weekly

•Instruments:

Photo camera

Plant Physiology Component 

Photosynthesis Campaigns

Plant physiology is an important component of our research. In order to understand how plant functions are altered by increasing temperatures and environmental disturbance (i.e. hurricanes) we evaluate processes like photosynthesis, under a ray of conditions.

•Purpose: 

Determine photosynthetic performance at different lights and temperatures.

 •Configuration: 

2 campaigns/yr.

Temperature Response Curve, Light Response Curve, & A-Ci Curves.

•Instruments:

LICOR 6800

Thermotolerance Campaigns

Leaf chlorophyll content meter (CCM).

Nicole Gutierrez performing chlorophyll content measurements.

Leaf chlorophyll content meter (CCM).

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Thermotolerance in plants refers to the ability to cope with temperature changes, and aspect we want to evaluate in some of our understory species and see how some of their functions are affected by the treatment. 

•Purpose: 

To determine how photosynthetic performance declines with increasing temperature.

•Configuration: 

2 campaigns/yr.

Hydrated and Non-hydrated.

•Instruments:

Chlorophyll content meter

FluorPen FP100