Soil surveys are an indispensable step for understanding the properties of land soil and ground. They are used across a wide range of fields from agriculture to construction and environmental measures, helping to determine appropriate land use and to design safe structures. This article organizes the purposes of "soil surveys" and the challenges of traditional methods, explains the advantages of real-time integration through cloud sharing, and describes efficient workflows using new technologies. Finally, using the smartphone-based centimeter-level positioning system LRTK as an example, we introduce the innovations that the latest technologies bring to soil surveys (centimeter-level accuracy (half-inch accuracy)).

Purposes and Main Uses of Soil Surveys

A soil survey involves collecting and measuring ground samples to examine the condition and characteristics of the soil. The purposes of surveys are diverse and play important roles in the following fields.

• Site selection and soil analysis for agriculture: pH levels and nutrient content are checked to determine whether soil is suitable for particular crops. In precision agriculture, fertilizer plans are optimized based on plot-by-plot soil data, leading to increased yields and resource savings.

• Ground assessment and construction planning: When constructing buildings or roads, surveys (such as boring investigations and standard penetration tests) are conducted to evaluate ground strength and stability. Understanding bearing capacity and soil layering provides the basis for appropriate foundation design and reinforcement decisions.

• Confirmation of soil contamination: On former factory sites or planned development areas, surveys check for soil contamination by hazardous substances. Based on laws (e.g., the Soil Contamination Countermeasures Act), historical land-use investigations and soil sample analyses are performed to obtain information necessary to implement remediation measures when needed.

• Detection and confirmation of buried objects: Surveys verify the presence of underground structures or buried waste. For example, they check whether old underground tanks or buried pipes remain, or use ground-penetrating radar to detect cavities or foreign objects. Identifying buried objects in advance reduces unexpected risks during construction.

Thus, soil surveys are carried out for a broad range of purposes, from farmland management to construction-site safety and environmental protection. Although requirements vary across fields, a common point is that accurate on-site information collection and sharing are essential.

Challenges in Traditional Soil Surveys

For many years, soil survey fieldwork has relied mainly on paper and manual processes. However, several issues have been identified with traditional methods.

• Time-consuming and dispersed data recording: Survey results were often noted in notebooks or on paper forms, and photos taken with cameras were managed separately, resulting in fragmented data. After returning to the office, these must be consolidated into Excel files or reports, which is time- and labor-intensive. Data on paper or USB drives are also at risk of loss, meaning valuable measurement results could be lost.

• Time lag in information sharing: A major problem was the time lag before field information reached the office. If surveyors only returned to the office at the end of the day to prepare reports, other team members or clients could not review the findings immediately, preventing instant decision-making. Unexpected issues encountered in the field could not be resolved on the spot, sometimes leading to the need for additional surveys later.

• Ambiguity of survey locations: Traditionally, survey points were plotted by hand on maps or recorded using on-site landmarks, making it difficult to reproduce exact locations. For example, a description like "about 50 m (164.0 ft) east of the XX tree" does not make it easy for someone else to identify the same spot later. Ambiguous location information can cause errors in re-surveys or additional sampling and risks overlooking important points.

• Linking photos to measurement data: Site photos are important evidence in soil surveys, but they were typically handled manually using file names or ledger numbers. Sorting large numbers of photos later and attaching the correct photo to the corresponding survey point in reports is cumbersome. If photo-linking mistakes occur, report accuracy is compromised.

These issues make it clear that traditional methods have limits in data management and information sharing. Relying on paper-based records and post-hoc reporting no longer fits the speed and accuracy demanded today. Against this backdrop, digital technologies have increasingly been introduced to soil survey sites in recent years to improve work efficiency.

Benefits of Real-Time Integration via Cloud Sharing

A powerful solution to the above issues is sharing survey data on the cloud. By storing and sharing data collected during surveys in the cloud, real-time information linkage between field and office becomes possible. Cloud utilization offers the following advantages.

• Immediate and centralized data sharing: Coordinates of survey points, soil observations, cross-sections, field photos, and analysis results can all be uploaded to the cloud and managed centrally. Because the latest information uploaded via the Internet can be viewed simultaneously by field teams and office staff, information transmission time lags are greatly reduced. There is no need to wait for email attachments or USB handoffs; data can be shared instantly during surveys. Since data are backed up in the cloud, the risk of data loss due to device failure or loss is also reduced.

• Real-time coordination between field and office: When data are updated in the cloud, engineers and staff in the office can view the latest information from a browser without installing specialized software. This allows the office to grasp the situation in real time while the survey is underway and to provide necessary instructions or decisions immediately. For example, if a report in the cloud states that a planned sampling point is inaccessible, an alternative point can be instructed immediately. This reduces unnecessary waiting times and schedule adjustments, improving the productivity of the entire team.

• Smooth information sharing with survey teams and clients: Some cloud platforms allow permission settings to share data with internal and external stakeholders. By sharing part of the survey results via the cloud with clients or partner companies, they can check progress without waiting for the final report. Issuing a dedicated viewing URL allows recipients to view data on the web without logging in (and download CSVs or images if needed). This early clarification of differences in understanding with clients leads to more transparent project management.

• Improved data history management and traceability: Data stored in the cloud are saved with timestamps and edit histories. It becomes clear who surveyed which point and what data were registered when, dramatically improving the traceability of survey operations. Even when verifying data later, the cloud history lets you reconstruct on-site activities. Accumulated data can also be analyzed to understand past survey trends and assist future planning.

By introducing cloud sharing, field and office are digitally connected, enabling a system that delivers the right information to the right people immediately. Not only is data management streamlined, but you also gain the major benefit of faster decision-making due to reduced communication loss.

Increased Reliability with GNSS and High-Precision Positioning

A factor that strengthens real-time integration is obtaining high-precision position information using GNSS. GNSS (Global Navigation Satellite System) refers to satellite positioning systems including GPS, and RTK (Real Time Kinematic), a high-precision positioning technology, has recently become practical. Using GNSS in soil surveys dramatically improves the reliability of survey point location information.

• Differences from traditional methods: Typical smartphone GPS can have errors of about 5–10 m (16.4–32.8 ft), but GNSS with RTK can determine positions with orders-of-magnitude better accuracy—horizontal accuracy of ± several centimeters and vertical accuracy of several centimeters to several tens of centimeters. This uses correction information from base stations and multiple-frequency satellite signals to cancel out positioning errors in real time. Centimeter-level positioning that once required expensive surveying equipment can now be achieved with compact GNSS receivers and smartphone apps.

• Improved trustworthiness of location data: Coordinates obtained with RTK-GNSS have very high reliability, allowing you to accurately associate survey results with locations. For example, in a soil contamination survey with 50 sampling points, recording the latitude and longitude of each sampling location precisely ensures that the sample from each point can be clearly traced to its analysis results. Eliminating positional uncertainty reduces ambiguity in data interpretation and enhances the credibility of survey reports.

• Reproducibility and fieldwork efficiency: High-precision coordinates enable you to return to the exact same point for re-surveys or additional sampling. This is useful for fixed-point environmental monitoring, improving the accuracy of year-to-year comparisons. Also, GNSS devices can navigate users to target points in the field based on pre-set survey plans in the cloud (for example, a coordinate list of grid-arranged sampling points). This allows comprehensive coverage of large survey areas efficiently and prevents overlooking points.

• Consistency of measurement data: Obtaining elevation data from GNSS allows accurate position correction for surface unevenness and boring excavation depths. Assigning unified coordinates and elevation to all survey data makes it easier to integrate and analyze data on GIS maps or cross-reference with other geographic information. Clarifying the spatial relationships between datasets contributes to more accurate overall assessments.

High-precision positioning using GNSS provides the foundation for rigorously recording "where and what was obtained" in soil surveys. The assurance gained replaces subjective judgments and manual processes with quantitative backing, and improving the reliability of location information is critically important from the perspective of overall survey quality control (QA/QC).

A Smart Workflow Connecting Field and Office

Combining cloud sharing and high-precision GNSS enables a new workflow in which the field and office operate as one. Below is a typical step-by-step flow.

• Pre-survey planning and cloud setup (office): Plan the survey area and points, and register candidate coordinates or map data in the cloud as needed. For a contamination survey, for example, divide the site into a mesh and decide sampling positions, preparing a coordinate list in the cloud. The office sets permissions for team members and prepares project folders to get ready for fieldwork.

• Field data collection (field): Surveyors log into a cloud-integrated app on smartphones or tablets to begin surveys. A high-precision GNSS device is connected to the phone, and while positioning themselves at centimeter-level accuracy (centimeter-level accuracy (half-inch accuracy)), they head to designated survey points. Upon arrival, they use the app to "record point," saving the point’s coordinates to the cloud with one tap. They enter notes about soil condition and collected samples and, if necessary, take and upload field photos. Photos and notes are automatically tagged with location and time, creating records that clearly show "when, where, and what was done." Data are sent in real time via mobile networks, and if out of coverage they are saved offline on the device and synchronized upon return to coverage.

• Immediate data review and feedback (office): As soon as data are sent from the field, office staff can view them almost in real time. The cloud map plots newly recorded survey points and allows instant access to photos and notes linked to each point. Staff can confirm whether the survey is proceeding as planned or whether unexpected problems have arisen. For instance, if a field note reports an unusual odor or discolored soil at a point, the office can immediately instruct additional sampling based on urgency via chat or phone. Conversely, if the field asks the office a question, the shared view allows instant answers. This two-way communication makes waiting for decisions virtually zero and enhances flexible on-site responses.

• Data accumulation, analysis, and report preparation (office): Once all points have been surveyed, the cloud contains the complete project dataset. Office technicians export the data for CAD drawings or GIS software, plotting results on maps and conducting analyses. Laboratory test results for soil samples can be attached to each sampling point in the cloud, completing a centralized dataset. Report writers pull necessary information from the cloud to create tables and graphs and compile the document. At this stage, simply copying photos or coordinate data from the cloud into reports reduces human errors such as incorrect photo placement or coordinate input. When submitting the final report to the client, you can provide cloud viewing accounts or limited-sharing links so they can electronically review all data if desired.

This workflow creates a collaborative environment where field and office, even when geographically separated, work as if side by side. Surveyors can focus on on-site recording while the office monitors progress and provides accurate support. This sense of speed and unity is a new value not achievable with traditional paper-based work.

Changing Soil Surveys with Centimeter-Level Positioning: Using LRTK

Finally, we introduce LRTK as a concrete tool that strongly supports the cloud-integrated soil survey described above. LRTK is a smartphone-based high-precision positioning system consisting of a small dedicated GNSS receiver called the LRTK Phone, a smartphone app, and cloud services. With this system, centimeter-level positioning that once required specialized equipment can be achieved with a palm-sized device and a smartphone.

Introducing LRTK to field soil surveys offers the following benefits.

• Accurate positioning by a single person: The LRTK is a lightweight device of about 165 g that can be attached to a smartphone, allowing field workers to perform high-precision positioning without aid from surveyors. Under suitable conditions, positioning accuracy can be about horizontal ±1–2 cm (±0.4–0.8 in) and vertical ±3 cm (±1.2 in), comparable to professional GNSS instruments. By starting the app and placing the receiver where the sky is open, it achieves high-precision mode (RTK fixed solution) in tens of seconds, enabling immediate positioning. The device requires no complex operations and is designed to be intuitive even for beginners.

• Data recording with location information: Coordinates obtained by the LRTK app are synchronized with the cloud in real time, and each point is automatically tagged with latitude, longitude, and elevation. The app also has a photo function that records the coordinates and orientation of the location where each photo was taken at the moment of capture. This prevents situations where photos exist but their locations are unknown, and ensures all field information is stored with spatial context. The reliability of survey points and the persuasive power of the data are greatly enhanced.

• Immediate data utilization through cloud integration: Data acquired by the LRTK system are safely stored and shared on the company’s LRTK Cloud. As in the workflow described above, seamless field→cloud→office integration speeds up information sharing among team members. LRTK Cloud also allows export of saved point lists and photos as CSV, JPEG, etc., so data can be immediately used in other analysis software or report preparation. It is a tool that supports DX (digital transformation) of soil surveys starting from the field level.

By leveraging smartphone-based high-precision positioning systems like LRTK, field soil surveys can be dramatically streamlined and data reliability improved. Moving away from paper- and manual-centered surveys to smart survey methods using cloud and GNSS is the trend demanded for the future. With real-time integration removing the barriers between field and office, everyone involved in a survey can act quickly while sharing the same information. That translates into faster decision-making, fewer mistakes and rework, and improved survey quality.

Sharing soil surveys on the cloud and achieving real-time integration is not just operational efficiency but a transformation of the survey process itself. With solutions like LRTK now capable of centimeter-level positioning (half-inch accuracy), reconsidering conventional field practices and proactively adopting the latest technologies is worth considering. In soil surveys where accuracy and speed are required, the combination of cloud and high-precision GNSS will be a powerful tool. Experience this new style of soil surveying at your site.