CN103848541B - The preparation method of a kind of hillside fields high-efficiency agriculture water filtering system - Google Patents

Abstract

The invention discloses a water filtration system composed of a collection field, a vegetation filter belt and a filter tank, wherein the vegetation filter belt is located between the flow collection field and the filter tank, and is used for filtering rainfall, runoff, eroded sediment and surface sources Pollutants, the filter tank is used to filter the firewood debris entering the vegetation filter belt, and the outlet water of the filter tank is connected to the water storage device; the length of the vegetation filter belt along the runoff direction is 5-7 meters, the width is not less than 3 meters, and the slope is not less than 3 meters. If it is greater than 1%, the vegetation filter zone adopts switchgrass, an energy-based forage grass with a planting coverage of more than 80%. Reaching 93.6% and 98.62%, the maximum interception effect on COD reaches 56%, and the interception effect on sediment and pollutants is obvious. If there are further requirements for water quality, activated carbon or medical stone layer can be added to the filter tank to improve water quality. Provide clean water for high-efficiency agriculture and form a circular and environmentally friendly economy.

Description

Preparation method of high-efficiency agricultural water filtration system for sloping land

technical field

The invention belongs to the technical field of water saving, water storage and water conservation in agricultural production and ecological environment construction in arid areas, and specifically relates to a preparation method of a new high-efficiency agricultural water filtration system for sloping land.

Background technique

In order to solve the ecological environment construction in many areas of our country in the process of large-scale implementation of returning farmland to forest and grassland, facing prominent problems such as population increase, land resources shortage, food security, and water security, many places such as the Loess Plateau are developing high-efficiency agriculture on sloping land in order to Efficient use of water and land resources. However, to develop high-efficiency agriculture in the Loess Plateau region, it is necessary to solve the shortage of water sources caused by drought and soil erosion, the high sediment content of water sources caused by erosion of sediment, the high cost of using rainwater to use sedimentation tanks, low efficiency of sedimentation, complex dredging, and easy damage , the difficulty of efficient utilization of water and sand, etc. It is an urgent need to seek an economical, environmentally friendly and ecologically clean water source filtration system that can not only utilize the nutrient-rich sediment carried by rainfall runoff to generate economic and ecological benefits, but also filter sediment pollutants and is inexpensive.

Contents of the invention

The purpose of the present invention is to provide a method for preparing a new high-efficiency agricultural water filtration system for sloping land, which conforms to the reality of sloping land in arid areas, can fully utilize local water and soil resources, develop circular economy, is practical and efficient, is eco-friendly, is convenient for construction, and is inexpensive.

In order to realize above-mentioned task, the present invention takes following technical solution:

A method for preparing a high-efficiency agricultural water filtration system on a sloping land, characterized in that the method uses a water collection field, a vegetation filter belt and a filter tank to form a water filtration system, wherein:

The catchment field is used to collect rainfall runoff;

The vegetation filter belt is located between the rain collection field and the filter tank, which is used to filter the eroded sediment and non-point source pollutants of the rainfall runoff, absorb the nutrient-rich substances in the rainfall runoff and prevent soil erosion;

The filter tank is used to filter the firewood and debris entering through the vegetation filter belt. The length of the filter tank is more than 3 meters, and the width and depth of the cross section are 30cm×50cm. The outlet water of the filter tank is connected to the water storage device;

In the filter tank, a sand filter layer composed of coarse-grained gravel above 20mm, coarse-grained gravel of 10-20mm, coarse-grained gravel of 5-10mm and coarse-grained gravel of less than 5mm is laid sequentially from bottom to top; Add sand filter layer;

The length of the vegetation filter belt along the runoff direction is 5-7 meters, the width is not less than 3 meters, and the slope is less than 1%;

The energy-based forage switchgrass with a height greater than 30 cm is planted in the vegetation filter zone, and the coverage rate of the energy-type forage switchgrass in the vegetation filter zone is more than 80%;

The planting of switchgrass, an energy-based pasture, is carried out in the following steps:

1) Along the runoff direction, a flat vegetation filter belt with a length of 5-7 meters, a width of no less than 3 meters, and a slope of no more than 1%. Dig and loosen the surface soil of the vegetation filter zone, remove weeds and sundries, and then apply base fertilizer on the vegetation filter zone. The base fertilizer should be phosphate fertilizer and potassium fertilizer and prepared according to the weight ratio of 1:1. The dosage per mu is 7.5kg~15kg, which is beneficial to energy Type pasture switchgrass plant seedling growth;

2) Select energy-based forage switchgrass seeds that have been stored for no more than 3 years and have a seedling emergence rate of more than 75%, sow them evenly at 0.8g to 1.0g per square meter and then rake them. The soil in the vegetation filter zone should be yellow loam or clay, and the planting depth is 1~2cm;

3) Pay attention to irrigation after sowing, and the irrigation frequency should be once a week to ensure the relative humidity of the 0-10cm soil layer and maintain the normal water holding capacity of the soil field; pay attention to controlling weeds at the seedling stage. After 30-45 days, the energy-based forage switchgrass will grow. As high as 30cm, the coverage rate of the vegetation filter belt is over 80%;

4) Switchgrass, an energy-based forage, is mowed once a year after autumn, and 30cm of stubble is left for the next spring to resume growth.

The agricultural water filtration system for sloping land constructed by the method of the present invention has high economic value by utilizing the energy-type forage switchgrass, and has a good interception and purification effect. By planting the energy-type forage switchgrass, a vegetation filter belt is formed to intercept rainfall runoff and sediment, and the vegetation filter belt absorbs runoff by Nutrients in sediment such as nitrogen, phosphorus and non-point source pollutants can accelerate growth and not only increase economic value (in this experiment, the yield of energy-type dry forage switchgrass can reach 1.445kg/m ² , and the income is 10-20 yuan/m ² ) , and the energy-based forage switchgrass intercepts sediment and eutrophication (N/P), supplements the nutrients needed for growth, provides clean water for efficient agriculture, and forms a circular and environmentally friendly economy. Through the filter tank, further filter the grass from the vegetation filter belt and the rainstorm runoff belt. If there are further requirements for water quality, medical stone or activated carbon can be added to the filter tank to improve water quality. Theoretical calculations and experimental tests have proved that the energy-based forage switchgrass has a maximum interception effect on sediment and total phosphorus of 98.62% and 93.6%, respectively, and a maximum interception effect on COD of 56%. It has an obvious interception effect on sediment and pollutants. The filter tanks with different particle sizes of sand and stones have high interception efficiency for large-scale firewood under the rainfall runoff zone in the vegetation zone, and the purification effect of filtered water pollutants varies with the addition of materials to the filter tanks.

The preparation method of the high-efficiency agricultural water filtration system for sloping land of the present invention is simple and convenient in construction, and the construction cost is 1/3 of the construction cost of the traditional grit chamber, the sand settling efficiency is increased by 30%-50%, and the management efficiency is increased by 300%-500% , requiring little administration. The vegetation filter belt formed by the energy-based pasture switchgrass is a perennial plant. Once planted, it can be harvested for many years. It can not only filter and utilize water and sand runoff, but also be used as an energy-based pasture and the raw material for extracting ethanol gasoline. More than 10, it overcomes the disadvantages of low sedimentation efficiency of traditional grit chambers, difficulty in removing sediment from complex structures, easy damage due to freezing, and high construction and repair costs that are difficult to promote. Its planting can be operated after simple technical training, and there is no engineering maintenance cost, which is convenient for application and promotion. It can replace the currently widely used farmland rainwater collection and sedimentation tanks that are expensive, inefficient and inconvenient to use, and has important practical significance and practical value for the development of high-efficiency agriculture on sloping land.

Description of drawings

Fig. 1 is a schematic diagram of the planar structure and vertical section structure of the high-efficiency agricultural water filtration system for sloping land of the present invention.

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Detailed ways

The core technology of the present invention is to use the energy-type forage switchgrass (Panicum virgatum L.) as a vegetation filter belt to cooperate with the filter tank. The vegetation filter belt is used to filter the eroded sediment and non-point source pollutants of rainfall runoff, and the filter tank further improves Water quality, providing clean water sources for efficient agricultural irrigation and even domestic water, to replace the current inefficient, high-cost, and inconvenient management of rainwater collection micro-settling ponds, and to provide high-efficiency agriculture for the development of slopes in the Loess Plateau and the vast arid and semi-arid areas with soil erosion Provide technical support with water.

Energy-based forage switchgrass (Panicum virgatum L.) belongs to the Panicum genus of the Gramineae subfamily (Panicoideae.A.Br), and is a perennial C ₄ warm-season grass plant. Due to its strong rhizome system, it has strong stress resistance and high utilization efficiency of water and nutrients.

The stalks of switchgrass, an energy-based pasture, grow upright and often grow in clusters. The height of the above-ground part can reach ^0.5-3.0m , and the dry weight output of biomass exceeds 1kg/m ² . , some studies have shown that the ethanol conversion capacity of energy-type forage switchgrass exceeds that of corn, and the production capacity of energy-type forage switchgrass per mu is equivalent to 3-4 tons of standard coal, and the average annual net energy output reaches 60MJ/m ² . Its root system can reach a depth of 3m, and has good ecological value of soil fixation and carbon fixation. Therefore, switchgrass, an energy-based forage grass, as a renewable clean fuel raw material, can reduce soil erosion and desertification, and has received extensive attention at home and abroad.

Compared with the ordinary vegetation filter belt, planting the vegetation filter belt of energy-based herb switchgrass has many advantages. The vitality of energy-based herb switchgrass is extremely tenacious, it grows rapidly, and it can grow in dry and poorly drained soil. , the cold resistance is also good, and the grass yield is large, which is 15 to 20 times that of ordinary grass. Energy-based forage switchgrass can be used as a pasture to develop the breeding industry. It can also be used to refine ethanol fuel and become an alternative energy source. The US Department of Energy and the Department of Agriculture regard it as a model plant for cellulosic ethanol conversion.

This embodiment provides a method for preparing a slope agricultural water filtration system, using a collection field 1, a vegetation filter belt 2 and a filter tank to form a filter system, wherein:

The catchment field 1 is used to collect rainfall runoff;

The vegetation filter belt 2 is located between the catchment field 1 and the filter tank 2, the length of the vegetation filter belt 2 along the runoff direction is 5-7 meters, the width is not less than 3 meters, and the slope is not more than 1%. Used to filter and absorb eroded sediment and non-point source pollutants from rainfall runoff;

The filter tank 3 is used to filter the firewood debris entering the vegetation filter belt 2 due to rainfall runoff, and the outlet water of the filter tank 3 is connected to the water storage device as a source of irrigation or even domestic water;

The length of the filter tank 3 is generally more than 3 meters, and the width and depth of the cross section are generally 30cm×50cm. In the filter tank 3, coarse-grained gravel above 20mm, 10-20mm coarse-grained gravel, 5- Sand filter layer composed of coarse-grained sandstone of 10mm and coarse-grained sandstone below 5mm (each thickness of the sand filter layer is 10cm); if the water quality requirements are high, special sand filter layer water treatment materials are required, such as medical stone or Activated carbon, etc.

Energy-based pasture switchgrass with a height greater than 30 cm is planted in the vegetation filter zone 2, and the coverage rate of the energy-type forage switchgrass in the vegetation filter zone is more than 80%;

The planting of switchgrass, an energy-based pasture, is carried out in the following steps:

1) The flat and gentle slope between the collection field 1 collecting rainwater and the filter tank 3 is 5-7 meters long and not less than 3 meters wide as the vegetation filter belt 2 (the slope of the vegetation filter belt 2 towards the water storage device is not greater than 1 %) As shown in Figure 1, the vegetation filter zone 2 is yellow loam or clay. Dig the surface soil of the vegetation filter zone 2, remove weeds and debris, and then apply base fertilizer. The base fertilizer should be phosphorus fertilizer and potassium fertilizer (calcium superphosphate and potassium sulfate ) and formulated according to the weight ratio of 1:1, the dosage per mu is 7.5kg-15kg, which is beneficial to the growth of the seedlings of switchgrass plants;

2) Choose switchgrass seeds that have been stored for no more than 3 years and have an emergence rate of more than 75%, sow them evenly at a rate of 0.8-1.0g per square meter and then rake them, and plant them in yellow loam or clay soil at a depth of 1-2cm;

3) Pay attention to irrigation after sowing, and the frequency of irrigation should be once a week to ensure the relative humidity of the 0-10cm soil layer and maintain the normal water holding capacity of the soil field; pay attention to controlling weeds at the seedling stage. After 30-45 days, switchgrass, an energy-based herbage Grow up to 30cm high, and the coverage rate in the vegetation filter zone 2 can reach more than 80%;

4) The energy-based forage switchgrass is used as a vegetation filter belt 2 on the one hand, and on the other hand, it can be used as an energy-based forage and a raw material for ethanol production. It is mowed once every autumn and leaves 30cm of stubble to restore growth in the next spring.

The theoretical calculation of the applicant and the planting practice on the Loess Plateau have proved that the energy-based forage switchgrass has a high interception capacity for rainfall, runoff, sediment and pollutants as a vegetation filter belt. Moreover, the energy-based forage switchgrass has high economic and ecological value and good interception and purification effect. By planting the energy-based forage switchgrass, a vegetation filter belt is formed to intercept rainfall runoff sediment. The vegetation filter belt absorbs nutrient-rich nutrients and non-point source pollutants in runoff sediment, Accelerated growth can not only increase economic value, but also supplement nutrients needed for growth by intercepting sediment and nutrient-rich substances, provide clean water for efficient agriculture, and form a circular and environmentally friendly economy. Through the filter tank, further filter the grass from the vegetation filter belt and the rainstorm runoff belt. If there are further requirements for water quality, activated carbon or medical stone can be added to the filter tank to improve the water quality until it can be used for drinking.

According to the applicant's experiment, the construction cost of this system is 1/3 of the construction cost of the traditional grit chamber, the sand efficiency is increased by 30%-50%, the management efficiency is increased by 300%-500%, and almost no management is required.

After simulated rainfall tests, the system has a high interception effect on sediment and pollutants, and the specific interception effect is shown in Table 1.

Table 1: Interception effect of the filtration system on rainfall runoff pollutants

Theoretical calculations and experimental tests prove that the maximum interception effect on sediment and total phosphorus reaches 98.62% and 93.6% respectively, the maximum interception effect on COD reaches 56%, and the interception effect on sediment and pollutants is obvious. The ordinary micro grit chamber can only play the role of settling sediment, and its interception efficiency can only reach 30%-50%, and the cost is high, and the maintenance cost is high; this system can not only increase the green area, reduce production costs, but also Effective interception and utilization of pollutants in rainfall runoff, the interception efficiency of sediment, total phosphorus, and COD can reach 90%, 85%, and 50% respectively. It can also harvest energy-based forage switchgrass to increase economic value. Compared with ordinary sedimentation The sand tank, which has a remarkable effect of intercepting sediment and pollutants, can effectively clean rainfall runoff and increase economic benefits.

After the water flow in the vegetation filter zone 2 is intercepted by the energy-based forage switchgrass, the sediment content is already very small, basically meeting the national requirements for drip irrigation on sediment content. If run into torrential rain, some firewood can be brought down from the vegetation filter belt 2, can fill some coarse-grained gravels in the filter tank 3 to intercept and filter and get final product. If there are special requirements for water quality, the sand filter layer in the filter tank 3 needs to be designed according to special requirements.

Claims (4)

1. a preparation method for Slopeland Agriculture use water filtering system, is characterized in that, the method adopts current collecting field (1), Vegetative Filter Strips (2) and filtering pond (3) composition to use water filtering system, wherein:

Current collecting field (1) is for collecting rainfall runoff;

Vegetative Filter Strips (2) is positioned between current collecting field (1) and filtering pond (3), for filtering erosion sediment and the area source pollutants of rainfall runoff, and the rich nutritive material absorbed in rainfall runoff and prevention soil and water loss;

Filtering pond (3) is for filtering the faggot and foreign material that enter through Vegetative Filter Strips (2), and the water outlet of filtering pond (3) is connected to water-storing device;

In filtering pond (3), lay more than 20mm coarse-grained sandstone, 10-20mm coarse-grained sandstone, 5-10mm coarse-grained sandstone from the bottom to top successively and be less than the sand filter blanket of the thick fine-grained sandstone composition of 5mm; With water quality requirement, suitably simplify or add sand filter blanket;

Described Vegetative Filter Strips (2) is 5 ~ 7 meters along the length of footpath flow path direction, and width is not less than 3 meters, and the gradient is less than 1%;

Plant in described Vegetative Filter Strips (2) and be implanted with the energy type herbage switchgrass being highly greater than 30cm, and this energy type herbage switchgrass in the fraction of coverage of Vegetative Filter Strips (2) more than 80%;

The plantation of energy type herbage switchgrass follows these steps to implement:

1) smooth Vegetative Filter Strips (2), the ground surface soil of Vegetative Filter Strips (2) is dug pine, cut weeds and foreign material, then apply fertilizer to the subsoil in Vegetative Filter Strips (2), base fertilizer selects phosphate fertilizer and potash fertilizer also by weight 1:1 preparation, every mu of consumption 7.5kg ~ 15kg, is conducive to the growth of energy type herbage switchgrass plant shoots;

2) select to deposit to be no more than 3 years, the energy type herbage switchgrass seed of seedling rate more than 75%, cross rake by after every square meter 0.8g ~ 1.0g uniform broadcasting, Vegetative Filter Strips (2) is yellow soil or clay, and planting depth is 1 ~ 2cm;

3) after planting note irrigating, irrigate the frequency and press per week 1 time, to ensure the relative humidity of 0-10cm soil layer, maintain soil field normal moisture capacity; Attentional manipulation weeds during seedling stage, after 30-45 days, energy type herbage switchgrass grows tall to 30cm, reaches more than 80% in the fraction of coverage of Vegetative Filter Strips (2);

4) after energy type herbage switchgrass flood in annual autumn, single cradles, and stays 30cm stubble, so as next spring restoration ecosystem.

2. the method for claim 1, is characterized in that, described current collecting field (1) comprise do not carry out special processing road, hillside fields or field.

3. the method for claim 1, is characterized in that, the length in described filtering pond (3) is more than 3 meters, and transversal face width is 30cm × 50cm deeply.

4. the method for claim 1, is characterized in that, described sand filter blanket is active carbon layer or medical stone layer.