Designed for Measurement Integrity

Beyond Automation.

Beyond Multiplexing.

From Soil Respiration to Ecosystem Carbon Exchange Partitioning

Measuring Carbon Is Easy.
Measuring It Correctly Is Difficult.

Over the past two decades, automated chambers have enabled continuous measurements, while distributed systems have improved spatial coverage.

Yet key sources of uncertainty remain.

Chamber-Induced Disturbance

Measurement systems should minimize their influence on natural gas exchange.

Spatial Variability

Carbon fluxes often vary substantially over short distances.

Representative Sampling

A single sampling point may not adequately represent the entire chamber environment.

Environmental Interpretation

Understanding why fluxes change often requires more than flux measurements alone.

The challenge is no longer measuring CO₂.

The challenge is measuring it correctly and understanding what drives it.

Designed Around Measurement Integrity

The PRI-8650 was developed to address key sources of uncertainty associated with chamber-based flux measurements.

Rather than focusing solely on automation, the system is designed to improve measurement quality at both the chamber and ecosystem scales.

Dynamic Pressure Equilibrium™

Designed to minimize pressure differences between the chamber interior and the surrounding atmosphere throughout the measurement cycle.

Helps preserve natural soil–atmosphere gas exchange conditions and reduce potential measurement artifacts.

Distributed Spatial Sampling

Multi-point gas collection architecture designed to improve chamber-scale concentration representativeness.

Helps reduce the influence of localized concentration gradients within the chamber.

Cylindrical Chamber Architecture

Designed to provide a consistent internal environment while minimizing corner effects and airflow discontinuities.

Supports stable and repeatable long-term measurements.

Designed to reduce uncertainty at its source.

 

One Platform.

Three Research Configurations.

Different scientific questions require different observation approaches.

The PRI-8650 platform supports three chamber configurations optimized for specific research objectives.

PRI-8650 Soil Respiration System

Opaque Chamber

Primary Output: Rs， Soil Respiration

PRI-8650C Net Ecosystem Exchange System

Transparent Chamber

Primary Output: NEE，Net Ecosystem Exchange

PRI-8650D Carbon Partitioning System

Dual Chamber

Primary Outputs: NEE， Reco， GPP

One Platform.

Multiple Perspectives on Carbon Cycling.

Understanding What Drives Carbon Fluxes

Carbon exchange does not occur in isolation.

Its variability is often controlled by interactions among radiation, temperature, moisture, and atmospheric conditions.

To support ecosystem process interpretation, the PRI-8650 data acquisition system can integrate environmental and meteorological measurements alongside carbon flux observations.

Available measurements include:

• PAR
• Air Temperature
• Relative Humidity
• Soil Temperature
• Soil Moisture
• Rainfall
• Wind Speed and Direction
• Atmospheric Pressure

Derived parameters include:

• VPD
• Dew Point

Environmental and meteorological integration packages are available as optional configurations.

Measuring carbon flux is important.

Understanding why it changes is even more important.

From Individual Plots to Ecosystem Understanding

Carbon cycling processes rarely occur uniformly across landscapes.

Single-point observations often fail to capture the variability that exists across ecosystems.

The PRI-8650 utilizes distributed independent measurement nodes that can operate individually or as coordinated observation networks.

Researchers can scale observations from individual plots to ecosystem-level investigations while maintaining standardized measurements throughout the network.

Applications

Forest Ecosystems

Long-term carbon cycling studies across heterogeneous landscapes.

Grasslands

Spatial variability and ecosystem productivity research.

Wetlands

Carbon exchange dynamics in complex environments.

Agricultural Systems

Management impacts on soil carbon cycling and ecosystem productivity.

Permafrost Regions

Climate feedback and carbon release studies.

Designed for High-Density Carbon Flux Observations.

 

Technical Specifications 

Technical Specifications

Measurement Configurations

Model	Chamber Configuration	Primary Outputs
PRI-8650	Opaque Chamber	Rs
PRI-8650C	Transparent Chamber	NEE
PRI-8650D	Dual Chamber	NEE, Reco, GPP

Gas Analysis

Parameter	Specification
Measurement Principle	Non-Dispersive Infrared (NDIR)
CO₂ Measurement Range	0–2,000 ppm
CO₂ Accuracy	±2% of Reading
H₂O Measurement Range	0–6%
H₂O Accuracy	±2%

Environmental Measurements

Parameter	Specification
Air Temperature	-40 to +85 °C
Soil Temperature	-40 to +85 °C
Soil Moisture	0–100%

Chamber Technologies

• Dynamic Pressure Equilibrium™
• Distributed Spatial Sampling
• Cylindrical Chamber Architecture
• Co-Located Dual-Mode SoilFlux System

Observation Network

• Distributed Independent Nodes
• Wireless Communication
• Network-Level Time Synchronization
• Cloud-Based Data Storage
• Remote Diagnostics

Power & Physical Specifications

Parameter	Specification
Power Consumption	12 W
Power Input	12 VDC
Solar-Powered Operation	Standard
Dimensions	45.4(L) × 27.3(W) × 23.5(H)cm
Weight	9.5 kg

Optional Environmental Monitoring

PAR | Relative Humidity | Rainfall | Wind Speed | Wind Direction | Atmospheric Pressure

Reimagining Soil Respiration Measurements

The PRI-8650 combines advanced chamber engineering, distributed observation architecture, and environmental monitoring into a unified platform for modern ecosystem carbon research.

Designed to help researchers obtain more representative carbon flux measurements while improving ecological interpretation across space and time.

PRI-8650

Distributed Soil Carbon Flux System

Designed for Measurement Integrity.

 

Beyond Automation.

Beyond Multiplexing.

 

Mastering Precision

Sensing Nature