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Yoshiyuki Miyazawa

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The following files contain source data for use of the Community Land Model 4.0 at two study sites in Volcanoes National Park, Hawai'i. Included are: Biometric data: 1) Growth increment data for Thurston and Olaa, based on dbh surveys done in four 10 m by 10 m plots at over a 12 year time period at Thurston and at six plots overs a 12 year period at Olaa, 2) Field measured leaf area index data. Measurements were made using LAI-2000 and LAI-2200 instruments, 3) Litterfall from Thurston and Olaa over a 17-mo period from June 2014 to Sep 2015. Data were sorted by species/litter type. Data are weights., 4) Field measured soil respiration data scaled to annual values and compared with tower-based measurements of ecosystem...
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The University of Hawaiʻi at Mānoa and the U.S. Geological Survey, in cooperation with the County of Maui Department of Water Supply and the State of Hawaiʻi Commission on Water Resource Management, initiated a field data-collection program to provide information for evaluating how rates of water vapor and carbon dioxide exchange are dependent on plant species type within forested areas on the island of Maui. The field data collection is part of a study to quantify the impacts of high-priority non-native and dominant native plant species on freshwater availability throughout the State of Hawaiʻi (https://archive.usgs.gov/archive/sites/hi.water.usgs.gov/studies/maui_eco/index.html). The overall objective of the study...
Cloud-water interception (CWI) is the process by which fog or cloud water droplets are captured and accumulate on the leaves and branches of plants, some of which drips to the ground. Prior studies in Hawai'i indicate that CWI is highly variable and can contribute substantially to total precipitation. In this study, we monitored CWI and other processes at five mountain field sites on the Islands of Oʻahu, Maui, and Hawaiʻi to explore how CWI (1) varies with different climate and vegetation characteristics, (2) affects plant water use and growth, and (3) contributes to water resources. Results show that annual CWI varied from 158 to 910 mm, accounting for 3-34% of total water input at individual sites. This large...
Categories: Publication; Types: Citation
Throughout the world, forests cover mountain slopes only up at a certain elevation. Above that level, trees become scattered. Higher up, no trees are found. The level where the forest ends, called the forest line or timberline, is higher in tropical areas than in colder regions, suggesting that cold climate conditions prevent forests from growing at higher elevations. On tropical island mountains, such as those in the Hawaiian Islands, the forest line is found at a lower elevation than we would expect based on the temperature. This leads us to suspect that some factor other than temperature, such as low rainfall, might be controlling the level of forest lines on these tropical islands. In this project, we sought...
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Cloud Water Interception in Hawai‘i - Part 1: Understanding the Impact of Fog on Groundwater and Ecosystems and Future Changes to these Processes
On Hawai‘i’s mountains, cloud droplets, propelled by strong winds, are deposited on plants, where they accumulate and drip to the ground, adding water over and above that supplied by rainfall. Prior studies show that the amount of intercepted cloud water is substantial, and variable from place to place. Estimates of the spatial patterns of cloud water interception (CWI), the fog-related effects on plants, and the contributions of fog to groundwater recharge and surface water flows are needed to better understand the water cycle and predict effects of climate change on water supply and ecosystems. We will make measurements of fog, wind, fog interception, soil moisture, and fog effects on plant water use and plant...
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