DE29815605U1 - Device for the detection of environmental pollution by evaluating chloroses and necrosis and the chlorophyll content on conifer needles - Google Patents

Description

Patent attorney Dipl.-Ing. Mario Wagner, Technology Center at Europaplatz, 52068 Aachen Applicant: Lemnatec GmbH
Attorney reference number: L12-005

Device for detecting environmental pollution by evaluating chlorosis and necrosis as well as the chlorophyll content of conifer needles

The invention relates to a device for the automatic image-analytical evaluation of biological markers (chlorosis and necrosis) on conifer needles and their measurement.

Such an evaluation of conifer needles serves, depending on the question, to determine the vitality of conifers, but especially to detect phytotoxic/plant-toxic effects of pure substances, mixtures of substances and environmental samples (water, water concentrates, soil, soil eluates and extracts, solids).

They enable the integral assessment of substances that are introduced into the environment or occur there in terms of potential hazards. The assessment of conifer needles is used to assess pollutant input from the air and rain in forest areas. For potential pollutant mixtures with a complex composition that cannot be comprehensively analyzed using chemical analysis - e.g. wastewater, landfill leachate, soil extracts, particularly from contaminated sites and their biological remediation products - combustion products (exhaust gases) from the chemical industry, energy producers and road traffic, integral effect tests for ecotoxicological assessment are indispensable.

The growth of terrestrial vascular plants is the vital basis for all animal and human life on earth. Nevertheless, the use of vascular plants to detect pollutants has so far been largely neglected compared to the use of unicellular algae. However, vascular plants are much more sensitive to auxin-analogous herbicides than unicellular algae, for example, because the latter do not have auxin-controlled growth regulation. The assessment of air pollutants is only possible through the quantitative recording of higher plants.

The reason for the less frequent use of vascular plants is, among other things, the greater variety of shapes and complexity of vascular plants, which has so far required manual optical and thus time- and cost-intensive and never completely objective evaluation.

The evaluation and measurement of necrosis and chlorosis as well as the chlorophyll content takes advantage of the high sensitivity of plants to toxic substances:

The state of the art is a manual evaluation of the optically detectable features. The measuring methods require a lot of work with little automation, poorly documented, subjective influencing factors and/or object-destructive measures.

The device according to the invention (see drawing) is characterized by complete compatibility with the existing test guidelines, avoiding the problems mentioned above while simultaneously creating new, more sensitive measurement variables. The automatic image analysis excludes subjective factors and the necessary personnel expenditure is drastically reduced. This makes multiple measurements possible without any problems and creates valid, continuous documentation.

The device used for this purpose consists of at least an adjustable lighting stage for transmitted and incident light, a camera, an image processing system, a monitor, a mouse and an interface for reading the measurement data into a standard computer for further data processing.

The computer-assisted image analysis records each conifer needle individually. Using image analysis methods, necroses and chloroses are then separated from healthy tissue and then quantified. Possible measurement variables are total area and length, relative and absolute proportion of chlorotic and necrotic tissue, the assessment of the degree of damage based on optical chlorophyll measurement, and the ecotoxicological assessment of the effects.

This makes it possible to detect, without additional work, effects that were previously difficult to detect, such as changes in the needle surface due to the influence of pollutants, which are only possible through the automated periodic measurement of all samples. This also enables automatic separation of healthy and damaged conifer needles.

Special markers are used to individually locate conifer needles. These markers are typical for a single needle and are determined and stored using image analysis, such as color spectrum, shape, absolute and relative proportion of chlorosis and necrosis, and absolute and relative chlorophyll content. These characteristics enable individual assignment of conifer needles during the next measurement.

When testing with sample trays, the test is evaluated by installing the camera in a horizontally movable carriage in the sample chamber. This allows fully automatic multiple measurements and the measurement and test evaluation on non-working days.

For planarization, a glass pane can be placed on the conifer needles or they can be fixed using a highly polar foil.

All raw data can be directly statistically evaluated.

To avoid confusion, a barcode can be attached to/in each vessel/test setup in the camera's field of view, which is then read during image analysis. In addition to information about the test setup, it also contains information about the computer-generated placement of the dish in randomized experiments.

Depending on the samples to be examined, the lighting is carried out as transmitted light or incident light. Infrared lighting is a special case. With infrared lighting, the needles can be checked and additional markers in the plant tissue can be detected.

For automatic calibration of the measurement value, a defined body can be placed in the bowl. The pixel values and their color values recorded by the image processing can be converted into absolute measurement values. This enables a comparison with manual evaluations.

Claims (7)

Patent attorney Dipl.-Ing. Mario Wagner, Technologiezentrum am Europaplatz, 52068 Aachen Applicant: Lemnatec GmbH Attorney file number: L12-005 PROTECTION CLAIMS: 1. Device for automatic image analysis of conifer needles and their vitality with and without the influence of potentially phytotoxic substances (pure substances, mixtures, environmental problems) in various matrices, characterized by an optical recording device that illuminates the sample dish with incident or transmitted light, planarizes the needles with a glass pane or a highly polar matrix if necessary, records them with a digital camera and passes the data on to an image analysis system for reduction and evaluation. 2. Device according to claim 1, characterized by means for automatically discriminating healthy and chlorotic as well as necrotic tissue, for the subsequent quantitative measurement of the detected markers in terms of length, width and shadow area and for measuring the chlorophyll content based on the data collected by means of image analysis. 3. Device according to claim 1 or 2, characterized by means for retrieving individual needles during periodic measurements of the same sample on the basis of specific shape features and information on the spatial variation possibilities between the measurements. 4. Device according to one of claims 1 to 3, characterized by barcodes arranged on/in the test units in the field of view of the camera, which are evaluated using image analysis to ensure reliable assignment of the individual measurements and, in addition to information on the test approach, also contain information on the computer-generated placement of the dish in randomized tests. : iuu t * &zgr; ··· *· 5. Device according to one of claims 1 to 4, characterized by a device for automatic calibration with a unit body of known body geometry and color by automatic measurement from the image processing, so that the plant data can be converted into absolute values. 6. Device according to one of claims 1 to 5, characterized by a lighting device for evaluation in a dark test environment with a wavelength range that does not influence the plants' behavior and in which the CCD camera works, so that the image analysis can also be carried out without visible light. 7. Device according to claim 6, characterized in that the lighting device is designed as an infrared lighting device.