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Kids using LandMapper to measure soil properties

Our first videos are accessible on YouTube now! Those introductory videos show how to use LandMapper for soil mapping and how simultaneously collect soil samples. It is so easy, even nine years old kids learned very quickly how to turn on the device and take measurements.

Story: Fourth graders from Bay Area Charter School in El Lago, TX were introduced to LandMapper - hand-held geophysical device - to assist them in undestanding soil properties and how they change during compaction. The project was undertaken in May 2012 to renovate high-traffic area near gym and playground of the elementary school. Kids learned how to make field observations and select areas with contrasting soil properties. They also learned that collecting soil samples by traditional methods is hard and "dirty" work. However, LandMapper can measure soil electrical resistivity (ER), a reciprocal of electrical conductivity (EC) - ER=1/EC - quickly and directly on the soil surface. Those electrical properties are related to many soil properties which reflect soil "health": compaction, stone content, salinity, fertility, texture, organic matter, and others. Using LandMapper to measure soil ER or EC prior to soil sampling can considerebly reduce time and effort in soil mapping and analysis. Best of all, LandMapper can be used anywhere - in farm fields, construction areas, flooded or frozen soils;  and by anyone - very little training is required!


BACES El Lago, TX 29° 34' 47.2656" N, 95° 2' 13.308" W

Evaluating cultivation level of sandy soils in European Russia with electro-geophysical methods

Electrical resistivity vs cultivation degree of sandy soils Update: Full PDF of the paper is now available!

Electrical resistivity of cultivated sandy soils of humid areas is a complex characteristic based on three fundamental properties of soil matrix, such as soil texture, total organic matter (carbon content) and cation exchange capacity (CEC). Relationship of electrical resistivity (ER) with those properties has been approximated with exponential equation ER=a*exp(-b*x), where x is any of the properties above. The correlation coefficients for ER as function of CEC, texture, or organic matter were between 0.82 and 0.91 for the soils of Klin-Dmitrov watershed near Moscow and Kirov, which suggests their applicability for other humid areas. We present a new approach to approximate exponential relationship ER=a*exp(b*x) with a linear “piece-wise” function based on the age of cultivation for each field.This approach was used to develop management zones based on ER to separate uniform areas of similar organic matter, CEC and clay content. Those basic properties are the foundation of soil fertility in humid areas. They influence biomass and bioactivity of soil microorganisms, thus the exponential relationship between ER and soil microorganisms was also observed. The approach based of electrical resistivity or conductivity was used to evaluate fertility and degree of cultivation of sandy soils in humid areas and for detail soil mapping and delineation of management zones in adaptive precision agriculture. The field and laboratory electrical geophysical methods are recommended for quick and accurate soil mapping and management in sustainable farming.

*at SAGEEP 2013, March 17-21 in Denver, CO, Larisa Golovko, Ph.D. will also present "Basic Theory of Measuring Electrical Resistivity, Conductivity and Self-Potential in Soils and Plants" with LandMapper ERM-02 and other commercially available geophysical equipment at post-conference workshop "Agricultural Geophysics: Theory and Methods".
SAGEEP 2013 logo
Cite this presentation as:

Anatoly Pozdnyakov, P.I. Eliseev, Larisa Golovko, Lev A. Pozdnyakov, Maria S. Dubrova, and E.P. Makarova. “Evaluating Cultivation Level of Sandy Soils in European Russia with Electro-geophysical Methods.” In New Views of the Earth. Denver, CO: Environmental and Engineering Geophysical Society, 2013.



Denver 39° 44' 15.2412" N, 104° 59' 4.9848" W
Klin, MOS 56° 19' 18.5304" N, 36° 42' 30.8772" E
KIR 58° 36' 16.8984" N, 49° 39' 58.5504" E

Happy New Year 2013 from Landviser LLC

LandMapper ERM-01 holiday sale - while supplies last!

We wish all our customers, friends, and collegues Merry Christmas, Happy New Year and wonderful holiday season!LandMapper is portable and scalable geophysical device

It has been a remarkable year for Landviser! We’ve completed several exciting projects with the focus on expanding capabilities of our LandMapper geophysical devices and helped many of our customers with their research. Our LandMapper geophysical devices have been gaining popularity around the globe. To extend our warmest Holiday wishes we are offering unprecidented discount of 20% on basic ERM-01 model from the current price of $1579. The new reduced price for ERM-01 of $1263 will be in effect until December 31, 2012 or while supplies last. Regular educational and dealers's discounts are still apply on the top of newly reduced price as stated in 

Current complete catalog of Landviser, LLC

To claim your ERM-01 now at a discounted price, email or call us (+1-609-412-0555) and mention promotion code 2012-12-ERM01. This offer is "first come, first serve" and is only available on pre-paid terms via credit card or wire transfer.Tax Deduction Info on www.Section179.Org!

Special Note for USA customers: Landviser's equipment and software qualify for tax deduction under Section 179. You still have time to purchase ERM-01, ERM-02 or RES2DINV/RES3DINV in 2012, before this deduction expires!

Landviser, LLC develops and sells portable handheld geophysical devices, Landmapper ERM-01 and ERM-02 for measuring electrical properties (electrical resistivity, conductivity, and potential)  in soils, plants and other semisolid and liquid media since 2003. This equipment is small, fully computer-integrated, and easy to use. It is very competitively priced and come handy many environmental, archaeological and agricultural applications, especially mapping and monitoring soil salinity and pollution. Information flyers can be downloaded from the links below:

More information on applications of both models is available in free publication in FastTIMES magazine:

Golovko, Larisa, Anatoly Pozdnyakov, and Antonina Pozdnyakova. “LandMapper ERM-02: Handheld Meter for Near-Surface Electrical Geophysical Surveys.” FastTIMES (EEGS) 15, no. 4 - Agriculture: A Budding Field in Geophysics (December 2010): 85–93.


Landviser LLC Houston 29° 45' 36.6948" N, 95° 22' 9.804" W

LandMapper ERM-02: handheld meter for near-surface electrical geophysical surveys (FastTIMES December 2010)

was published in December, 2010 issue of FastTIMES, online peer-reviewed journal of EEGS. To cite this publication use:FastTIMES dec 2010 Agriculture: A budding field in Geophysics

Golovko, Larisa, Anatoly Pozdnyakov, and Antonina Pozdnyakova. “LandMapper ERM-02: Handheld Meter for Near-Surface Electrical Geophysical Surveys.” FastTIMES (EEGS) 15, no. 4 - Agriculture: A Budding Field in Geophysics (December 2010): 85–93.

Registered users can download PDF of full text of proceedings paper from our website. Or browse online version below and leave your comments. You might also like to go to EEGS website to get PDFs of other publications on applications of geophysics to near-surface environmental problems published in this popular FREE online scientific magazine.


On-the-go sensors, designed to measure soil electrical resistivity (ER) or electrical conductivity (EC) are vital for faster non-destructive soil mapping in precision agriculture, civil and environmental engineering, archaeology and other near-surface applications. Compared with electromagnetic methods and ground penetrating radar, methods of EC/ER measured with direct current and four-electrode probe have fewer limitations and were successfully applied on clayish and saline soils as well as on highly resistive sandy soils, such as Alfisols and Spodosols. However, commercially available contact devices, which utilize a four-electrode principle, are bulky, very expensive, and can be used only on fallow fields. Multi-electrode ER-imaging systems applied in deep geophysical explorations are heavy, cumbersome and their use is usually cost-prohibited in many near-surface applications, such as forestry, archaeology, environmental site assessment and cleanup, and in agricultural surveys on farms growing perennial horticultural crops, vegetables, or turf-grass. In such applications there is a need for accurate, portable, low-cost device to quickly check resistivity of the ground on-a-spot, especially on the sites non-accessible with heavy machinery.


Laramie, WY 41° 18' 40.9212" N, 105° 35' 27.9636" W

Low-cost GPS logger

I had tested a small gadget called GPS logger from Columbus Visiontac. Complete product name-description is:

Product name

Product Features

Where to buy


Columbus V-990 GPS Data Logger (microSD Slot, Voice Recording, 66 ch. MTK)


  • A good data logger still needs practical track processing software. Time Album attached to V-990 can help you freely process track.Time Album has various personalized settings.
  • It can export track according to distance or time, select metric or imperial unit or record intervals, and support various operating systems including WINDOWS, MAC OS and LINUX.
  • V-990 adopts the currently most advanced and stable MTKII 3329 super single chip, with only 35s and 1s required respectively for cold start and warm start.
  • It can realize rapid and stable positioning under various environments including urban district and suburb.
  • The built-in high-capacity Li-polymer battery can allow you to use the device all day (24hrs).

Columbus V-900 Bluetooth GPS Data Logger (microSD , Voice Tag for POI, Driverless, Push to Log, 25 millions waypoints*, XP / Vista/ Linux / Mac OSX Compatible)

  • 51 channels MTK chipset with enhanced positioning system technology (up to 1.5m accuracy with EPS Technology
  • Voice-Tag function with built-in microphone allows adding live voice labels to any waypoint
  • MicroSD Slot with support up to 2GB* capacity (about 25,000,000 waypoints, more than 2 years) *NOTE: 1GB microSD card is optional in the package
  • Push-To-Log (POI anchor key) enables you to mark a POI at any time
  • Unique SPY mode allows continuous standby logging of more than one month


Seatle 47° 36' 22.356" N, 122° 19' 55.4556" W
32° 19' 45.2136" N, 142° 1' 52.5" E

Electrical Fields and Soil Properties (17th World Congress of Soil Science)

The most downloadable PDF publication on Landviser, LLC website is our proceedings paper on 2002 World Congress of Soil Science. So we decided to publish it on our site as our first interactive eBook. It a short synopsis of our research on application of electrical geophysical methods to study soil genesis and provides theoretical background to all applied case studies. To cite this presentation use:

Pozdnyakov, Anatoly, and Larisa Pozdnyakova. “Electrical Fields and Soil Properties.” In 17 World Congress of Soil Science, Symp. 53:Paper #1558. Bangcock, Tailand, 2002.
Registered users can download PDF of full text of proceedings paper from our website. Or browse online version below and leave your comments. You might also like to go to IUSS website to get PDFs of other publications on World Congress of Soil Science.


The electrical fields in the surface of soils appear as many different kinds. Methods of self- potential (SP), electrical profiling (EP), vertical electrical sounding (VES), and non-contact electromagnetic profiling (NEP) was used to measure the electrical properties of basic soil types, such as Spodosols, Alfisols, Histosols, Mollisols, and Aridisols (USA Soil Classification) of Russia in situ. The density of mobile electrical changes, reflected in measured electrical properties, was related to many soil physical and chemical properties. Soil chemical properties (humus content, base saturation, cation exchange capacity (CEC), soil mineral composition, and amount of soluble salts) are related to the total amount of charges in soils. Soil physical properties, such as water content and temperature, influence the mobility of electrical charges in soils. The electrical parameters were related with soil properties influencing the density of mobile electrical charges in soils by exponential relationships based on Boltzmann's distribution law of statistical thermodynamics (r=0.657-0.990). Generally, the electrical methods can be used for in situ soil mapping and monitoring when the studied property lone highly influences the distribution of mobile electrical charges in the soil. The electrical properties were used to improve soil characterization for soil morphology and genesis studies; to develop accurate soil maps for precise agriculture practices; and to evaluate soil pollution, disturbance, and physical properties for engineering, forensic, and environmental applications.


Bangcock 13° 45' 7.9992" N, 100° 29' 38.0004" E
59° 44' 53.8008" N, 41° 23' 47.3424" E

Instrumentation, Electrical Resistivity (Solid Earth Geophysics Encyclopedia)

Our unique LandMapper device was featured in 2nd edition of Solid Earth Geophysics Encyclopedia as the best small scale portable and accurate electrical resistivity/conductivity meter. To cite this publication use:

Loke, M.H., J.E. Chambers, and O. Kuras. “Instrumentation, electrical resistivity.” In Solid Earth Geophysics Encyclopedia (2nd Edition), Electrical & Electromagnetic, Gupta, Harsh (ed), 599–604. 2nd ed. Berlin: Springer, 2011.

The PDF of the article is attached to this webpage. Continue reading excert from the Encyclopedia....


Instrumentation, Electrical Resistivity

  • Electrical survey. Mapping subsurface resistivity by injecting an electrical current into the ground.
  • Resistivity meter. An instrument used to carry out resistiv­ity surveys that usually has a current transmitter and volt­age-measuring circuitry.
  • Electrode. A conductor planted into the ground through which current is passed, or which is used to measure the voltage caused by the current.
  • Apparent resistivity. The apparent resistivity is the resistiv­ity of an equivalent homogeneous earth model that will give the same potential value as the true earth model for the same current and electrodes arrangement.
  • Multi-core cable. A cable with a number of independent wires.


The resistivity survey method is more than 100 years old and is one of the most commonly used geophysical explo­ration methods (Reynolds, 1997). It has been used to image targets from the millimeter scale to structures with dimensions of kilometers (Linderholm et al., 2008; Storz et al., 2000). It is widely used in environmental and engi­neering (Dahlin, 2001; Chambers et al., 2006) and mineral exploration (White et al., 2001; Legault et al., 2008) sur­veys. There have been many recent advances in instru­mentation and data interpretation resulting in more efficient surveys and accurate earth models. In its most basic form, the resistivity meter injects a current into the ground through two metal stakes (electrodes), and mea­sures the resulting voltage difference on the ground sur­face between two other points (Figure 1). The current (I) and voltage (V) values are normally combined into a single quantity, the apparent resistivity, which is given by the following relationship:


Berlin 52° 31' 9.0156" N, 13° 24' 21.9276" E
8° 0' 14.8032" S, 108° 32' 41.7192" E

LandMapper ERM-02 - versatile and affordable

Landmapper - field EC meter with lab accuracy

Don’t break your back collecting soil samples. Reduce amount of samples sent for laboratory analysis and save money. And still make detail soil map of your fields, which will be more accurate than conventional soil surveys. Impossible? Not at all with LandMapper ERM-02.
This device measures three important electrical properties of soil: electrical resistivity (ER), conductivity (EC), and potential (EP). Utilizing the most accurate four-electrode principle LandMapper measures ER or EC and helps delineate areas with contrasting soil properties within the fields quickly, non-destructively and cost-efficiently.

In a typical setting, a four-electrode probe is placed on the soil surface and an electrical resistivity or conductivity value is read from the digital display. Using the device prior to soil sampling you can significantly reduce the amount of samples required and precisely design a sampling plan based on the site spatial variability.
Bulk soil EC was correlated with salinity, texture, stone content, bulk density, total available nutrients, water holding capacity, and filtration rates. Guided by detailed soil EC map obtained with LandMapper, only minimal amount of soil samples is needed to invert EC map into correlated soil properties. Also, LandMapper can be used to measure EC in soil pastes, suspensions and solutions and quickly estimate total dissolved salts (TDS) in solid and liquid samples.


Beltsville 39° 2' 5.3952" N, 76° 54' 26.9064" W
34° 57' 16.8984" N, 91° 38' 52.6164" W
56° 17' 1.7628" N, 36° 59' 27.4812" E

How to fix: Windows 7 loads default instead of user-modified profile wiping off all settings, files, email accounts, bookmarks

I repeatedly run into the “default user profile instead of my user settings” problem with Windows 7. Once in a while when I log in onto my user profile on my Win 7 computer, it logs into default user profile and all my settings in web browsers, office files and other software is gone! MS Outlook asks me to set up all the email accounts over again! My documents directory is empty, but all files still can be found in C:\\Users\myusername… So what is the problem and how to fix it quickly? Last time it happened I googled solution and quickly learned that this is pretty common problem for Windows 7, and the only fix is to edit Registry. Now as it happen again this morning I could not found exact instructions on the web again, so after frantic searching for solution (and finally fixing my PC), I decided to post it on my blog in IT tips section… 

One of the people posted in a forum, almost as an after-thought, all tucked away where, if you didn’t take the time to read thoroughly, you’d miss it:

“I solved my problem by going into the registry and delete the effected profile’s subfolder under:

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList”

Note: HKLM refers to “HKEY_LOCAL_MACHINE” in the registry.

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