environmental-biophysics

Champions of water potential Drs. Kim Novick and Jessica Guo team up to discuss the vital role water potential measurement plays in both plant and soil sciences and the work they are doing to establish the first-of-its-kind nationwide water potential network. Join their discussion to understand how a communal knowledge of these measurements could impact what […] The post Building a National Water…

Environmental Biophysics – Lecture 18 Lecture Summary In this lecture, Jolene Lafferty introduces water vapor fluxes, gives theoretical examples and explains practical measurement methods. About the Lecturer Jolene Lafferty is the Director of Divisional Operations at METER Group.

Environmental Biophysics – Lecture 29 Lecture Summary In this lecture, Dr. Doug Cobos demonstrates how to measure net radiation and thermal radiation. Dr Cobos also discusses the benefits and drawbacks of different real world methods for measuring thermal radiation. About the Lecturer Dr. Cobos is Director of R&D at METER Group and an adjunct professor in the Department of Crop and Soil Sciences …

Environmental Biophysics – Lecture 7 Lecture Summary In this lecture, Dr. Doug Cobos talks about different methods and sensors for measuring atmospheric humidity. Methods include capacitance type sensors, psychrometers, hair hygrometers, infrared gas analyzers, chilled mirror dew point sensors, and lithium chloride cells. About the Lecturer Dr. Cobos is Director of R&D at METER Group and an adjun…

Environmental Biophysics – Lecture 26 Lecture Summary In this lecture, Dr. Doug Cobos discusses energy balance and methods to measure short wave radiation, including pyranometers, thermopiles, and photometric sensors. About the Lecturer Dr. Cobos is Director of R&D at METER Group and an adjunct professor in the Department of Crop and Soil Sciences at Washington State University.

Environmental Biophysics – Lecture 10 Lecture Summary In this lecture, Dr. Doug Cobos continues the discussion about water potential along the soil-plant-atmosphere continuum. In the second half of the lecture Dr. Cobos reviews various instruments that are used to measure water potential including pressure bombs, tensiometers, thermocouple psychrometers, and dew point hygrometers. About the Lectu…

Environmental Biophysics – Lecture 21 Lecture Summary In this lecture, Dr. Doug Cobos lectures on the thermal properties of soils— thermal conductivity, specific heat, thermal diffusivity, thermal admittance— and calculations using these measurements. About the Lecturer Dr. Cobos is Director of R&D at METER Group and an adjunct professor in the Department of Crop and Soil Sciences at Washington S…

Environmental Biophysics – Lecture 30 Lecture Summary In this lecture, Dr. Colin Campbell gives an analysis of view factors as they pertain to net radiation. About the Lecturer Dr. Campbell is Vice President of R&D at METER Group and an adjunct professor in the Department of Crop and Soil Sciences at Washington State University.

Environmental Biophysics – Lecture 9 Lecture Summary In this lecture, Dr. Colin Campbell provides an introduction to water potential. Well, first he reviews a quiz from a previous class. The material on water potential starts at 13:33. Feel free to skip ahead. After defining water potential, Dr. Campbell starts to discuss how it can be used to understand plant-soil water interactions. About the L…

Learn the difference between intensive and extensive variables and how they relate to soil water potential vs. soil water content in our new Chalk Talk whiteboard series. In this video series, Dr. Colin S. Campbell teaches basic principles of environmental biophysics and how they relate to measuring different parameters of the soil-plant-atmosphere continuum. Watch the […] The post Chalk Talk: In…

Named for the tall pine tree that sits at the top of the tumulus earth mound, Takamatsuzuka Tomb is located in the Asuka village, just south of Nara, Japan. Located within the tomb are some of the most beautiful and famous Japanese wall paintings. Discovered in 1972, the paintings are believed to have been made at the end of the seventh and beginning of the eighth centuries. Though it […] The pos…

Modern technology has made it possible to sample Normalized Difference Vegetation Index (NDVI) across a range of scales both in space and in time, from satellites sampling the entire earth’s surface to handheld small sensors that measure individual plants or even leaves. NDVI – Global The broadest way to think of NDVI is data obtained […] The post Get More From Your NDVI Sensor appeared first on …

Greenhouse growers need irrigation strategies to maintain high plant quality, but it’s difficult to obtain quantitative information on exactly how much water will produce the highest-quality growth. Estimating irrigation needs by using reference evapotranspiration calculated from environmental factors and a crop coefficient is standard for controlling field crop irrigation, but in a greenhouse th…

Estimating the relative humidity in soil?  Most people do it wrong…every time.  Dr. Gaylon S. Campbell shares a lesson on how to correctly estimate soil relative humidity from his new book, Soil Physics with Python, which he recently coauthored with Dr. Marco Bittelli. A number of years ago a former student told me of a meeting […] The post Estimating Relative Humidity in Soil: How to Stop Doing…

In the conclusion to last week’s blog, Mark Blonquist, chief scientist at Apogee Instruments and air temperature measurement expert, explains the complexities of some proposed solutions to the problems that challenge accurate air temperature measurement. Solution:  Passive Radiation Shield In addition to an accurate sensor, accurate air temperature measurement requires proper shielding and ventil…

Understanding the amount of drainage that comes out of the bottom of the root zone and infiltrates into groundwater recharge is a very difficult measurement to do well. Drain gauges do a good job of it but on a small scale. Large lysimeters do an even better job, but are extremely expensive and complex.  There is an […] The post Using The Salt Balance Approach to Measure Soil Drainage appeared fi…

In China recently, a fellow scientist asked Dr. Colin Campbell if matric potential sensors work in frozen soils.  His answer? Sort of. In this blog, he explains what he meant by his enigmatic reply: When water freezes in the soil, most matric potential sensors won’t work accurately because frozen water essentially disappears to the measurement. For example, […] The post Measuring Frozen Water Pot…

In a continuation of last week’s article “Understanding Avalanches,” we find out what conclusions Dr. Ed Adams and his colleagues in Montana State University’s avalanche studies program were able to make about measuring the thermal conductivity of snow. In order to study the thermal properties of snow samples, the research team wanted a way to measure […] The post Understanding Avalanches: Therm…

Reading through our archives the other day, I came across this article about thermal conductivity and snow. It’s a unique application for a thermal properties analyzer, an interesting story, and something that may ultimately even save the lives of backcountry skiers and snowboarders. When Wired Magazine wrote up Dr. Ed Adams and his colleagues in February […] The post Understanding Avalanches: T…

Several years ago I had the chance to work at the USDA ARS Research Watershed in Riesel, Texas. The goal of my research was to look at the effects of land use and landscape position on water infiltration.  Within the research watershed there is preserved and maintained native prairie, improved pasture, and conventional tilled areas, […] The post Double Ring Infiltrometers Versus DualHead Infiltro…