Comparison between traditional water treatment technology and water ecological in-situ purification technology?

Soilless lawn ecological landscape floating island for river and lake pollution control

Eutrophication of water body is a global water environment problem. There are more than 2,700 lakes in China with a total area of 965,438+0,000 km2. According to the survey data and the evaluation indexes of lake eutrophication at home and abroad, 55.8% of the 37 typical lakes in China are moderately eutrophic and moderately eutrophic, 14.7% is eutrophic and 8.7% is severely eutrophic. Ecological landscape floating island is based on floatable materials, and its purification principle is to use plant roots with large surface area to form dense nets in water, absorb a large number of suspended substances in water, and gradually form biofilm on the surface of plant roots. Microorganisms in biofilm swallow pollutants in water and metabolize them into inorganic substances. Nitrogen, phosphorus and organic pollutants in water are reduced by absorption or adsorption of plant roots, and are converted into plant cell components through photosynthesis to promote their growth. Finally, the floating island plants are harvested. The research results at home and abroad show that the water purification efficiency of ecological floating island is more than 70% higher than that of constructed wetland under the same area. At present, "ecological floating island", "artificial floating island", "artificial biological floating bed", "biological floating bed" and "floating bed soilless culture" appearing in some documents are all the same or similar concepts.

After decades of research and development, the ecological floating island technology at home and abroad has been greatly improved, but for various reasons, the ecological floating island technology is still in the experimental and demonstration stage, and there are some problems and shortcomings in its use:

1. The existing ecological floating island culture is not easy to standardize, popularize and apply. Different lakes and rivers have different degrees of eutrophication, and water flow, temperature, wind speed and water level fluctuation all need corresponding floating island design combinations and floating island plant species collocation, so it is difficult to formulate unified standards for popularization and application.

2. The existing ecological floating island is difficult to implement mechanized operation. Ecological floating islands float on the water surface, and daily management is completed on the water surface. At present, most of its management operations are done manually, and the cost of management and maintenance is high, which is acceptable in small-scale experimental demonstration. If it is popularized in a large area, it needs to be harvested frequently and timely, and manual operation can not meet the needs, which limits its development.

3. The existing ecological floating island has a long production and construction period. At present, most ecological floating islands adopt the mode of on-site production and on-site planting, and the period of large-scale production and construction is long.

4. The existing ecological floating islands are difficult to survive the winter. Most plants on the ecological floating island can't survive the winter and need to be replanted in the following spring, especially in the northern part of China where the winter weather is cold.

5. Most of the existing ecological floating islands use large aquatic plants and vegetables, which are difficult to resist extreme winds, heavy rains and big waves.

6. At present, the single area of ecological floating islands used at home and abroad is small, and most of them are used in small rivers and lakes, so it is difficult to carry out ecological restoration on larger rivers and lakes. Now there must be an ecological floating island with a large area.

Beijing Zhumengyuan Roof Soilless Greening Technology Co., Ltd. makes use of the special advantages of soilless lawn and adopts its own patented technology to make ecological floating islands with soilless lawn. The experiment proves that it has achieved good results, solved many problems existing in the production technology of ecological floating islands at home and abroad, and achieved the following results;

1. Soilless lawn ecological floating island is a perennial plant with strong adaptability, which has the potential advantage of purifying eutrophic water. Because the lawn height of soilless lawn ecological floating island is not high, the root system is developed and the lawn structure is firm, it can resist extreme wind, rainstorm and big waves, and can be used under any conditions such as water flow, temperature, wind speed, water level fluctuation and eutrophication.

2. Soilless lawn ecological landscape The floating island adopts soilless lawn cultivated on the ground, and the lawn is combined into a floating island module in the factory. According to the required area of the construction site, as long as the adjacent floating island modules are connected together, the required ecological landscape floating island can be made. This manufacturing method makes the construction on the project site more convenient and fast.

3. Because the floating island of soilless lawn ecological landscape is made of flat soilless lawn, the landscape floats on the water after it is made, which is uniform, like a green carpet, and the landscape effect is very obvious.

4. Soilless lawn ecological landscape floating island is the only ecological floating island that can be made on a large scale at home and abroad because of its special structure and convenient management, which can effectively repair larger rivers and lakes.

5. The ecological landscape of soilless lawn on the unfrozen water surface south of the Yangtze River in China is evergreen all the year round. Our experiments in Beijing proved that the average winter temperature in Beijing in 20 12 was the lowest in 30 years, and the extreme minimum temperature reached below-15 for several days. The soilless lawn on the frozen water surface was frozen into ice, but all the lawns turned green in the experiment in the spring of 20 13. It should be noted that plants on various ecological floating islands at home and abroad cannot survive this winter.

6. The ecological landscape floating island of soilless lawn is also lower than the ground lawn in terms of maintenance and management. The lawn laid on the ground 1 is afraid of drought and lack of fertilizer, and the maintenance and management consumes a lot of water and manpower, while the ecological landscape floating island without soil lawn will not have these problems. The ecological floating island of soilless lawn is made of gramineous cool-season grass, which has high temperature and humidity in summer and high incidence of cold-season lawn diseases when used on the ground. If the maintenance measures are improper, it will cause a large area of alopecia areata and seriously affect the lawn landscape effect. Because the lawn of ecological floating island without soil grows on the water surface of lakes and rivers, the water surface temperature of lakes and rivers is far lower than that of the ground, and the lawn is not easy to get sick and the pests are far lower than that of the ground lawn even in summer with high temperature. Ecological landscape of soilless lawn Floating islands can be used for many years after being laid on the water, just like lawns planted on the ground. Even if there is bald spot on the lawn, the experiment proves that sowing grass seeds can be restored without covering and managing the lawn. The management of ecological floating island without soil lawn is simple, and the longer the service life, the higher the economic and social benefits.

7. The ecological landscape floating island made of soilless lawn has smooth surface and sufficient buoyancy. When used on a large scale, workers can mow the lawn 20-30 times a year according to the growth of the lawn. The results showed that the chlorophyll content, leaf water content, dry weight, density and coverage of the soilless lawn of Festuca gramineae under hydroponics were significantly higher than those under soil culture, and the lawn was mowed more times each year than the ground lawn, which could remove more nutrients from the water. The ecological landscape floating island of Gramineae soilless lawn is an effective new way for eutrophication restoration of large rivers and lakes.

8. Soilless lawn ecological landscape floating island has many incomparable advantages over existing ecological floating islands at home and abroad. It also has extremely high environmental economic value, resource value and social value, and has broad popularization and application prospects at home and abroad.