TWM525048U - Root system measurement device for artificial-wetland plant - Google Patents

Description

Root measuring device for constructed wetland plants

The novel creation belongs to the field of ecological engineering technology, and specifically relates to a root measuring device for artificial wetland plants.

Constructed wetland wastewater treatment technology appeared in the 1970s. Constructed wetlands have good sewage purification effects, and their construction and operation costs are lower than traditional sewage treatment methods. Thus, its application has grown rapidly since the 1990s. However, the complex interaction processes and mechanisms of plants, microorganisms, soil substrates, and pollutants in constructed wetlands are still unclear. At present, there is a special lack of research on plant roots in wetlands, such as the growth, distribution and biomass of plant roots in wetlands and the role of roots in wetland wastewater treatment. Previous studies have suggested that the rhizosphere of wetland plants is an active area where plants, microorganisms, substrates and pollutants interact, and is therefore the most active area for wastewater purification. The density and distribution of roots are related to the physical, chemical and biological properties of the wetland matrix, and root growth is considered to be one of the decisive factors in assessing the potential of wetland plants for wastewater treatment. However, there is currently little understanding of the roots of constructed wetlands, and the root zone of constructed wetlands is still considered a "black box."

The purification function of wetland plants is related to the degree of development of roots. Plants with developed roots and long roots can expand the space of artificial wetland to purify sewage, which is beneficial to microorganisms, especially Aerobic bacteria are placed deep in the wetland to improve their ability to purify the sewage. Therefore, in the selection of wetland plants, the root growth should be fully considered. According to the research of leveling, the roots of Typha and rush are mainly distributed in the area of 25cm. The roots of wetland plants are mainly distributed within 25cm, which provides a reference for the construction of constructed wetlands.

In the soil matrix, the biomass of the root system is usually obtained by drilling the soil sample or excavating a certain volume of the soil sample by excavation, separating and measuring the root amount in the soil sample. The amount of root growth in the soil matrix is usually obtained by burying the soil column method, periodically taking out the buried soil column, separating and measuring the root amount in the soil column. In the soil column method, the sum of the biomass of the roots measured several times in one year is taken as an estimate of the amount of growth. The biomass of the roots measured three times can be regarded as an estimate of the amount of root growth. However, it is likely to be a lower estimate because there may be a small amount of root death between the three measurements and not included in the assay. Tanner estimates that the life of sewage treated constructed wetland roots is approximately four months. The study of plant roots can also use excavation methods, soil drilling methods, etc., but these methods can not timely understand the changes in plant roots.

Subsurface flow constructed wetlands generally have greater load capacity and better purification effects than surface flow wetlands, and thus have a wide range of applications. Therefore, it is necessary to study the root distribution, biomass and growth of subsurface flow constructed wetland by appropriate methods, and to explore and improve the role of plant roots in sewage purification.

In order to timely understand the changes in plant roots in the constructed wetland matrix and to periodically measure the biomass of the plant roots in the constructed wetland substrate, the present novel provides a device for measuring the root system of constructed wetland plants.

The technical means for creating the novel is as follows: a root measuring device for a constructed wetland plant, wherein the device is a column having a top opening, and a plurality of through holes are uniformly disposed on a side wall and a bottom surface of the column, and the root measurement is performed. The device is made of a transparent material.

The aforementioned cylinder is a cylinder.

The aforementioned cylinder is a prism.

The above-mentioned cylinder is a quadrangular prism, the through hole has a hole diameter of 5 cm, and the through holes are arranged in a plurality of columns on each side, the column pitch is 7 cm; the pitch between the through holes in each column is 4 cm; The aforementioned through holes on the bottom surface are arranged in a plurality of rows with a line pitch and a pitch of 4 cm.

The through holes on each side are arranged in three columns in three columns; the pitch between the through holes in each column is 4 cm; and the through holes are arranged in three rows on the bottom surface.

The novel creation provides a root measurement device for measuring the root system of a constructed wetland plant. The device is a column with an open top end, and a through hole is provided on the bottom surface and the side surface, and the device is supported by a transparent material.

In the novel creation, the cylindrical shape of the device is optional. Since the growth of the roots grows radially to the surroundings, the foregoing apparatus preferably employs a symmetrical prismatic or cylindrical structure and a transparent material to facilitate observation of the root system from various angles. The function of the through hole is to form a connecting channel between the wet substrate and the external substrate in the device, which is beneficial to the exchange of nutrients, water, oxygen and the like, and reduces the root growth of plants in the device and other locations in the artificial wetland region. The roots of the plant grow in a difference between the environment, thereby maximizing the availability of reliable measurements. On the other hand, it is also convenient to cut the sampling during the measurement of root length and thickness.

When the root device of the constructed wetland is monitored by the aforementioned device, the aforementioned device is vertically installed. It is placed in the artificial wetland matrix, and the upper part reaches the surface of the substrate or is slightly lower than the surface of the substrate, and is placed smoothly. It is not used in conventional devices in the prior art, and the device described in the novel creation has the greatest feature of planting wetland plants into the aforementioned devices. When the root system is measured, the above device is taken out, and root growth and distribution can be observed, and the biomass of the root can be measured. The biomass measured at intervals can be used as an estimate of the production volume, and the sum of the biomass measured multiple times a year can be used as an estimate of the annual production.

The prior art "buried soil column method" uses the sum of biomass of roots measured several times in one year as an estimate of the amount of growth. The biomass of the roots measured three times can be regarded as an estimate of the amount of root growth. However, it is likely to be a lower estimate because there may be a small amount of root death between the three measurements and not included in the assay. Tanner estimates that the life of sewage treated constructed wetland roots is approximately four months. In addition, it is also possible to have a certain damage to the roots outside the column and affect their growth rate. Of course, this situation also exists in the buried soil column method.

The root measuring device described in the novel can periodically observe the root system without damaging the root system of the plant, and timely understand the changes of the whole root system of the plant.

Compared with the buried soil column method used in the conventional soil matrix, it is easier to remove the root growth substrate, and it is easier to separate the root from the growth substrate, and the measured volume is more fixed and accurate. In addition, the distribution and growth of each root can be clearly observed, which cannot be achieved by embedding the soil column method. Compared with soil drilling sampling, it has the following advantages: it is more convenient and labor-saving to use; since its position is completely fixed, the measurement is more accurate; since it is fixed, the growth amount of roots can be determined for a certain period of time. In summary, the device for monitoring the root system of constructed wetland plants described in the novel is a device capable of effectively studying root growth, distribution, biomass and production of constructed wetland plants.

Fig. 1 is a schematic view showing the structure of the bottom surface of the root measuring device according to the first embodiment of the present invention.

Fig. 2 is a side view showing the structure of the root measuring device described in the first embodiment of the present invention.

The present invention will be further described in detail below with reference to specific embodiments, but does not limit the scope of the novel creation.

Embodiment 1 The best solution of the root measuring device described in the novel creation

The foregoing device is a top open cylindrical body made of plexiglass, and the bottom surface and the side surface thereof are provided with holes whose height is less than or equal to the height of the artificial wetland substrate. The specific structure of the foregoing device is: 31 cm in length; 31 cm in width, 43 cm in height, and 5 mm in thickness.

As shown in Fig. 1, the bottom surface of the device has a specific structure of three rows (horizontal axis) and three columns (vertical axis), three small holes per row, and the vertical and horizontal axes are spaced apart by 4 cm.

As shown in Fig. 2, on the four sides of the device, a plurality of circular holes are drilled for root growth. The specific parameters of the side structure are: 3 rows (horizontal axis) 3 rows (vertical axis) on each side, 3 small holes in each row, 7 cm in the vertical axis, and 4 cm in the horizontal axis. The pores of the bottom and side surfaces of the aforementioned device have a pore diameter of 5 cm.

Example 2 Monitoring plant roots of Typha angustifolia and plant using a plant root measuring device

(1) Select measurement points in the constructed wetland area and take out artificial wetness at the measurement point Ground matrix, the root measuring device of Example 1 is embedded in the pit, the upper part of the device reaches the surface of the substrate or is slightly lower than the surface of the substrate, and is smoothly placed; (2) the cattail or yellow bud is planted into the device, and then The excavated constructed wetland substrate fills the aforementioned device and does not exceed the upper edge of the device; (3) sampling is performed in July, September and November, respectively, and growth observation and biomass measurement are performed on the root system. The planting period of cattail and yellow flower iris in constructed wetland is February, April and June. Three strains were sampled each time, for a total of nine strains.

Observe the distribution of root system: when measuring, layer 0-5cm, 5-15cm and >15cm from the surface of the substrate, observe the distribution of roots, cut out the live roots in the device, and put them in airtight plastic. Inside the bag. After the roots of the plastic bag were brought back to the laboratory, all the root samples were baked in a 80 ° C oven to a constant weight and then weighed.

Determination of above-ground biomass of wetland plants: When measuring, cut the plants at the near surface, weigh the dead parts of each plant and the fresh weight of the live plants, and weigh 100-200g of fresh weight samples from different organs of each plant. After drying in an oven at 80 ° C to constant weight, the dry weight was weighed. Rinse with tap water and blot the water on the root surface with absorbent paper. Separate the diameters by <1mm, 1~3mm and >3mm. Weigh the fresh weight with the electronic scale (Shanghai Tianping Instrument Factory, FA1104) and put all the root samples in The dry weight is weighed after drying to a constant weight in an oven at 80 °C.

The root number, root length, root biomass and root surface area of the root system were determined: the number of roots and the root length were measured once a week. The number of roots is determined by counting the number of roots per plant, and the root length is the longest root of each plant. Cut at the junction of the rhizome and group the roots according to the diameter of the root by a vernier caliper (diameter d<1mm, 1mm<d<3mm, d>3mm, rhizomes), rinse with clean water (tap water), use absorbent paper The water on the surface is sucked, and the fresh weight is called the fresh weight. The sample of about 100g was dried (80 ° C, 48 h), and the dry weight was weighed by an electronic scale (Shanghai Tianping Instrument Factory, FA1104 type). The volume of each group was measured by the drainage method, and the root surface area was determined by the formula S=4V/d. Statistical analysis of the data obtained.

It can be seen from the experimental results that the pore size of the device is suitable, but the height is preferably adjusted to the height of the selected plant, although in this experiment, the root distribution is not more than 30 cm, and other studies have considered that few roots are distributed in 30cm or less. In constructed wetlands that have been growing for many years, the root distribution is likely to be deeper.

Claims (5)

A root measuring device for a constructed wetland plant, characterized in that the device is a column having a top opening, a plurality of through holes are uniformly disposed on a side wall and a bottom surface of the column, and the root measuring device is made of a transparent material. The root measuring device according to claim 1, wherein the column body is a cylinder. The root measuring device according to claim 1, wherein the column body is a prism. The root measuring device according to claim 1, wherein the column body is a quadrangular prism, and the through hole has a hole diameter of 5 cm, and the through holes are arranged in a plurality of columns on each side surface, and the column pitch is 7 cm; the pitch between the through holes in each column is 4 cm; on the bottom surface, the through holes are arranged in a plurality of rows, and the row pitch and the pitch are 4 cm. The device of claim 4, wherein the through holes are arranged in three columns in each column on each side; the pitch between the through holes in each column is 4 cm; The aforementioned through holes are arranged in three rows.