Recommended Free Tools
Kauri forests may take up carbon faster per hectare than other New Zealand native forest types, but the available comparison does not show that every kauri forest already holds more carbon than every other native forest. A 2025 review estimated annual sequestration rates; separate studies of carbon already stored show wide variation between kauri stands. Those are different measures, and the estimates are limited by sparse kauri-specific data and incomplete coverage of forest carbon pools.
What the comparison says about annual carbon uptake
A 2025 Northland Regional Council and University of Auckland desktop review estimated these annual sequestration ranges for New Zealand forests:
| Forest category in the review | Estimated annual sequestration | Source and qualification |
|---|---|---|
| Natural kauri forests | 0.7–40.6 Mg CO₂ ha⁻¹ yr⁻¹ | Northland Regional Council / University of Auckland desktop review, 2025; literature-derived estimate, with uncertainty that the review says can be as high as 50%. |
| Other New Zealand native forest types | −4.4–3.9 Mg CO₂ ha⁻¹ yr⁻¹ | Northland Regional Council / University of Auckland desktop review, 2025; range for the other native forest types included in its compilation, with uncertainty that can be as high as 50%. |
The estimates suggest higher potential annual uptake for natural kauri forests in this comparison, especially at the upper end. The ranges overlap, however, and the kauri range is broad. They are not results from a controlled, like-for-like measurement of every forest type, so they do not establish a universal ranking.
Carbon stored is not the same as carbon taken up each year
Carbon stock is the amount held in a forest at a particular time. Sequestration is the rate at which carbon is added over time; the review reports this as carbon dioxide per hectare per year. A stand can have a large stock without having the highest current annual uptake, and a high per-hectare rate alone does not tell you which forest type contributes the most across New Zealand. Total contribution also depends on how much area each type covers.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
In a 1999 study of four kauri forest remnants, Silvester and Orchard reported 64–990 tonnes of carbon per hectare above mineral soil. The sites ranged from pole stands to mature forest. This is an observed range from four remnants, not a current national average or a direct stock comparison with all other native forests. The National Library of New Zealand record reproduces the study abstract.
The study also reported total dry matter, including forest floor, of 132–2,290 tonnes per hectare; that is a biomass measure, not the same as tonnes of stored carbon. Its oldest stand had as much as 546 tonnes per hectare of forest-floor litter and humus. These figures illustrate why the material included in a measurement matters.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Which carbon pools are counted?
A forest carbon total may include living trees, dead wood, litter, roots and soil. Comparisons are meaningful only when the pools and methods align. The 1999 kauri study’s reported carbon range is explicitly above mineral soil, while the 2025 review says missing root and soil studies prevent calculation of whole-ecosystem sequestration rates from the available evidence.
- Living trees and dead wood: included in New Zealand’s official forest inventory approach.
- Forest-floor litter and humus: reported separately in the four-remnant kauri study; do not conflate dry matter with carbon.
- Roots and soil: not adequately covered by the studies cited in the 2025 review for a complete kauri ecosystem sequestration estimate.
How New Zealand estimates forest carbon
The Ministry for the Environment says its forest inventory uses permanent sample plots on a forest sampling grid. Living trees and dead wood are measured, and plot data are converted into carbon per unit area using methods developed for that purpose. The Ministry uses different estimation methods for natural and planted forests, including allometric equations and modelling techniques. See its forest carbon measurement guidance.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
The Ministry’s natural forest report describes estimates based on pre-1990 natural forest plot data collected in cycles spanning 2002–2007 and 2009–2014. A national inventory estimate and a measurement from an individual kauri stand answer different questions; one should not be treated as the other.
Why the kauri estimates remain uncertain
- The 2025 review says the LUCAS permanent-plot network contains only a small number of kauri-dominated forests.
- Some sequestration estimates are derived from forest growth and stem density using general allometric equations. The review identifies model uncertainty and measurement error, with uncertainty as high as 50% of an estimate.
- The lack of root and soil studies means the reported rates should not be read as complete ecosystem carbon budgets.
- The review says no study had examined the effects of biosecurity threats on kauri forest carbon at stand scale. Kauri dieback may affect growth and carbon dynamics, but a quantified forest-scale loss is not established by the evidence it discusses.
The review is available as the 2025 Northland Regional Council / University of Auckland technical report. The Department of Conservation describes ongoing work on more accurate forest locations, remote-sensing protocols, long-term changes in carbon pools and the effects of introduced browsers on its native ecosystem carbon storage programme; that work indicates active measurement efforts, not a revised published kauri-versus-native comparison.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
How to interpret other prominent kauri figures
Waikato Regional Council gives figures of 1,306 tonnes per hectare from biomass measurements and 1,326 tonnes per hectare from carbon equations for one 69-year-old Taranaki kauri plantation. Those values are specific to that stand and method; they are not typical natural-forest values and are stocks, not annual sequestration rates. Details appear on the Council’s planted native forest carbon calculator page.
A 2009 Department of Conservation report assigned 8.6 million tonnes of carbon reserve to a mixed “kauri/manuka/kanuka” vegetation category. Because that category combines vegetation types and comes from an older national compilation, the figure cannot be attributed to kauri alone or presented as a current kauri total. The report is available as a Department of Conservation PDF.
Quick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
