82results about How to "Reduce wind erosion" patented technology

A method for eliminating the Cd pollution of soil by use of solanum features that the black nightshade is planted in the Cd polluted soil for enriching the Cd pollutant and the mature black-nightshade is removed, so eliminating the pollution of soil.

The invention relates to a method for soil-column seedling culture and transplanting afforestation, wherein the transplanting afforestation method comprises the following steps of preparing soil-column blocks, using the soil-column blocks to cultivate tree / shrub seedlings and transplanting soil-column-block seedlings on site. The method can avoid the damage of bare-rooted seedling transplantation to tree root systems, as well as the problem of root-system coiling problem caused by container seedling transplantation, can enable transplanted seedlings to form root-system forms similar to self-generated trees so as to improve the survival rate of the seedlings and the adaptability of the seedlings to new environments, can avoid the destruction of fish-scale pits and other traditional afforestation methods to ground surface, and can reduce soil wind erosion. The method can be used for general flat-land afforestation, as well as slope-land, sandy-land and wasteland afforestation, and has obvious social, economic and ecological benefits.

A mechanized cultivation method with three-year rotation of crops for the northeast features that for the first year, the field is prepared in the later autum, the seeds are sowed in the spring and the crops are harvested in the autum, for the second year, the stubbles are broken and returned back to field in the later auttom, seeds are sowed in the spring and the crops are harvested in the autum, and for the third year, the stubbles are broken in the field and the seeds are sowed in the spring, and the crops are harvested in the autum. It can preserve the moisture in soil for high yield.

The invention discloses a method for storing moisture and preventing drought in a dry farming spring corn area. According to the method, after autumn crops are harvested, fertilizer applying, deep tillage, rake grinding and applying of chemical herbicide are performed in the late autumn and early winter according to the requirements for sowing plastic-film corn in spring of the next year, a plastic film is timely covered, hole sowing is directly performed on the film during sowing in spring of the next year, and harvest is performed in autumn. The method has the benefits as follows: by means of the provided method for storing moisture and preventing drought in the dry farming spring corn area, the water and moisture storing capacity can be enhanced, the soil moisture environment is improved, sowing in the optimum period and full stand of corn are guaranteed, the stress resistance of corn is enhanced, and the corn yield and the water use efficiency are improved. With the application of the method, the capacity of dry farming spring corn in the north of China in adapting to drying and warming of climate is improved, and the method has a very important significance in stable increase production and high yield of the corn in the dry land.

The invention relates to a planting method for crops, in particular to a wide-row flat planting protective tillage planting method for maizes. The planting method comprises the following seven steps of: performing land preparation, sowing, rolling after sowing, weeding by pesticides, subsoiling mechanically and performing side deep fertilizing, preventing and controlling diseases and insect pestsand harvesting mechanically. In the planting method, the conventional 60-centimeter uniform ridge planting mode is changed into a flat planting mode of 80-centimeter row pitch and 20-centimeter row spacing, and ventilating and light-transmitting space of the crops is increased; the conventional shallow intertillage and shallow fertilization mode is changed into a mechanical deep scarification anddeep topdressing mode, namely the conventional three-shovel three-time intertillage management and shallow fertilization operation is changed into one-time deep scarification and deep topdressing operation, so operation links are reduced, and the production cost is reduced; the conventional sowing mode is changed into a zero-tillage sowing mode, so the evaporation of soil moisture is reduced, andthe capacity of drought resistance and soil moisture conservation is improved; the conventional mode that harvested low stubbles are crushed to return to a field into a mode that mechanically-harvested high stubbles are rotten naturally to return to the field; and before sowing, seeds are processed by using a plasma seed processing technology to improve the germination percentage of the seeds.

The present invention relates to a rainwater-collecting, water-supplying and water-saving vadose irrigator, it is made of plastic material and its outer form is similar to tree. Said rainwater-collecting, water-supplying and water-saving vadose irrigator can be used for irrigating trees and orchard. It includes the following several portions: rainwater-collecting surface, collecting flow-guiding pipe, water storage tank, vadose irrigation flow-guiding pipe and vadose head which are connected into one body. Said water-collecting surface is formed from plastic tree leaves. Said invention also provides the working principle of said vadose irrigator and its concrete operation method.

The invention discloses a high-yield planting method for preventing and treating corn stem rot in semi-arid regions, belonging to the technical field of agricultural planting and culturing. The high-yield planting method comprises the following steps: land selection and preparation, seed selection, seed treatment, ridging, base fertilizer application, seeding, drop irrigation, water feeding, weeding, membrane lamination, top application, field management, corn stem rot prevention, harvesting and the like. According to the high-yield planting method, the problem that the seeding emergence rate of corns in the second year is influenced by the total straw application of straws is solved; by processing corn seeds, the emergence rate can be improved by more than or equal to 5%, and the straw turnover in the second year is not influenced; the preventing and treating effect of the corn stem rot reaches more than or equal to 70%; water is saved by more than or equal to 40%, and the corn yield is increased to be 800-1000 kilograms per hectare; adverse factors caused by the ecological environment to the agricultural production are overcome, the traditional agricultural production mode is changed, the unit yield is increased, the yield and the efficiency are increased, and the effects of reducing wind erosion of soil, protecting the environment and improving the drought resisting capacity and the production stability of crops are achieved.

The invention belongs to the field of crop planting, in particular to a high-efficiency corn cultivation method in saline-alkali land. The high-efficiency corn cultivation method in the saline-alkaliland includes the following specific cultivation steps: soil improvement, flat land preparation and application of base fertilizer, corn sowing and film covering, irrigation and fertilization. The method achieves the aim of improving corn emergence rate, seedling preservation rate, water and fertilizer utilization efficiency and further improving corn yield by improving the corn planting method and optimizing the irrigation and fertilization system, breaks through the technical bottleneck of difficult corn planting and improvement in saline-alkali land in low-lying areas, and can play a technical supporting role in efficient improvement and utilization of saline-alkali land and improvement of ecological environment. On the one hand, ridge film furrow planting can effectively reduce the evaporation and consumption of soil moisture, and thus water collection and moisture preservation are favorable, so that crop yield and water use efficiency are improved; on the other hand, the utilization of groundwater can be further promoted, the groundwater level is lowered, and the phenomenon of soil salinization is reduced.

The invention discloses a wind prevention, sand fixation and water retention afforestation method and belongs to the technical field of environmental protection engineering. The method comprises steps as follows: a curing agent is prepared from sodium carboxymethylcellulose, anionic polyacrylamide, ferrous chloride and water; the curing agent and sand are blended to form cured sand; deep holes for tree planting and shallow trenches for grass planting are dug in the sand land, water collecting hoppers are drilled in the deep holes, the deep holes and the shallow trenches are filled with the cured sand, and the cured sand form deep hole sand fixation and water absorption layers in the deep holes and form shallow trench sand fixation and water absorption layers in the shallow trenches; saplings are planted in the deep holes, the roots of the saplings extend into the mouth parts of the water collecting hoppers, and grass seeds are scattered in the deep holes and the shallow trenches; the grass seeds are covered with a mulching film for maintenance, and small ventilation holes are formed in the mulching film. The curing agent and the sand soil are blended, inside gaps of soil particles can be filled with the blended curing agent and sand soil, the cured sand particles don't easily disperse and jump, sufficient water can be continuously provided for plants, and the long-time wind prevention, sand fixation and water retention effects are achieved.

The invention relates to a sowing technique, in particular to a stub no-tillage mechanical sowing cultivation method. The wheat stub no-tillage rape cultivation method comprises the steps of mechanically harvesting wheat, mixing selected rape seeds, chemical fertilizers and sheep dung, sowing rape seeds, performing rape field management, harvesting and the like. The method has the advantages of increasing soil moisture, reducing wind erosion and water and soil loss, regulating ground temperature, increasing nutrients in soil, improving activity of soil enzymes, preventing lodging, increasing forage grass and the like.

The invention relates to a sandy soil improving method. The adopted technical scheme is as follows: (1) adding a certain amount of grass carbon and straws into fresh sludge until C (Carbon) / N (Nitrogen) ratio is (25-35):1 and water ratio is 45-55%, adopting a natural ventilation mode, turning for one time every 10 days, turning for more than five times, and maintaining the temperature of sludge pile at 55 DEG C for more than 10 days so as to obtain rotten sludge; and (2) before spring ploughing, applying the rotten sludge with the applying ratio of 2-15kg / ha-1 into sand, mixing the rotten sludge and the sand being about 20cm in depth uniformly, compacting, smoothening soil surface, watering the soil surface completely, and standing for about a half moth to obtain the improved sand soil. According to the sand soil improved by the method, the mechanical composition is improved, the sand clay content is increased, the content of organic matter is increased obviously, the nutrient contents of N, P, K and the like are improved obviously, the soil bulk density is reduced, the porosity is improved, and the water storage amount in the soil is increased.

The invention discloses a cultivation method of water-saving irrigation for corn. The method comprises following steps: (1) selecting lands; (2) selecting certified seeds suitable for the local condition; (3) processing seeds; (4) mounding; (5) laying drip irrigation pipes; (6) deep ploughing and conserving water with soil; (7) applying base fertilizer; (8) covering film and sowing; (9) irrigatingand topdressing; (10) reasonably close planting and economically using water; (11) enhancing field management to enhance drought resistance: (a) early thinning and final thinning; (b) intertillage for promoting root; (c) management of fertilizer and water; (d) covering with film and grass; (e) preventing and controlling disease and pests; (10) harvest. The method of the invention improves the unit yield, realizes increasing production and efficiency, and has the functions of reducing soil wind erosion, protecting the environment and improving the drought resistance and stable yield of crops;according to the growth law and nutrient requirement of maize, the planting method, fertilizer application method and field management method of maize were optimized, and the yield of maize was improved obviously.

The invention discloses a method of building a field biological fence, which mainly includes: sequentially planting ceratoides latens, cereal crops and potato at intervals in a plot from west to east, namely transplanting seedlings of the ceratoides latens from west to east, planting the cereal crops to the east and planting the potato to the east; repeating sequential planting of the three types of crops from west to east. The transplanted ceratoides latens is clipped once three years before reviving in spring, stalks of the cereal crops are maintained 15cm-20cm in height during harvest in autumn, ploughing and leveling are performed after the potato is harvested, and accordingly the field biological fence is formed. The method is simple in operation, has the double functions of increasing yield and income and protecting field ecological environment, and is practically suitable for northern dry farming areas to develop characteristic commercial crops and expand forage grass production.

The invention discloses a corn straw total crop straw return protective farming method. A corn harvester with the straw crushing and returning function is adopted for harvesting during the autumn harvest in first year, meanwhile, the crushed corn straws are uniformly thrown into the field, and the ground surface is covered; ploughing and soil preparation operation is carried out; stubble ploughing, straw cutting and mix burying, subsoiling, soil preparation, compacting and the like are completed at one time; in the spring period in the second year, direct seeding is carried out, multiple worksuch as fertilization, precision seeding, soil covering, compacting and the like can be completed at one time; a nitrogen fertilizer is applied between the seedlings by a topdressing machine during the growth period of the corns. According to the method, the straw cutting segments are uniformly mixed in the soil of the tilling layer, so that the ground temperature can be improved, the straw rotting is accelerated, the diseases and pests are reduced, and meanwhile a certain surface straw coverage rate can be guaranteed, wind erosion and water erosion are reduced, and the purpose of protecting the soil is achieved, the method is especially suitable for being applied and popularized in regions with low winter and spring temperature in the northeast, and a technical support is provided for large-area popularization and protection of the regions.

The invention relates to a sand wind speed reducing plate, a sand-preventing barrier, a manufacturing method of the sand wind speed reducing plate and application of the sand wind speed reducing plate and the sand-preventing barrier. The sand wind speed reducing plate comprises high density polyethylene, uvioresistant additives and optional coloring agents, wherein the thickness of the sand wind speed reducing plate ranges from 1mm to 4mm, and flow guide holes are distributed in the sand wind speed reducing plate. The manufacturing method of the sand wind speed reducing plate comprises the steps of (1) burdening, (2) drying and mixing of raw materials, (3) extrusion, (4) press polishing, (5) punching, (6) drying and (7) detection. According to the invention, the sand wind speed reducing plates are fixedly arranged between stand columns and press plates through bolts, and the stand columns are fixedly arranged in desert soil, so that the wind-speed-reducing sand-preventing barrier which can continuously extend is formed. The sand wind speed reducing plate and the sand-preventing barrier are applied to highways, railways, municipal services and sand stabilization and afforestation engineering in the regions such as desert, gobi desert and oasis edges.

The invention provides a vegetaion cultivation device which comprises a base package and a cylindrical nutrient ring, wherein a soil improvement rod is arranged in the nutrient ring and is connected with the nutrient ring by virtue of multiple segregation boards; and during use, the nutrient ring is arranged on the base package. The vegetaion cultivation device can be used for ecological remediation of engineering construction lands and lots of bare slopes, the survival rate of plants under chilly conditions is guaranteed, a stable slope plant community is constructed, the ecological remediation effect is good, and the requirement on ecological environment restoration of bare surfaces caused by engineering construction in alpine regions is met.

The invention relates to a method for controlling wind erosion of nursery stock bases in desert areas. The method relates to a nursery stock sand storm protection cover which comprises a cover body, a cover edge and a fixed drill rod, wherein the cover body is shaped like a round table; the cover edge is arranged at the bottom of the cover body; and the fixed drill rod is inserted into a fixed hole on the cover edge and then fixed in soil on the earth surface. After a nursery stock is planted in a desert area, the nursery stock sand storm protection cover is taken, and the cover body and a gap on the side wall of the cover edge are slightly unfolded to horizontally move toward the nursery stock; branches of the nursery stock are collapsed and pass through the gap; the cover body is arranged around the nursery stock; the protection cover is rotated to ensure that the gap on the protection cover is toward the downwind direction of the local predominant wind direction; and along with the growth of the nursery stock, when the sand storm protection cover limits the growth of the trunk, the cover body and the gap on the side wall of the cover edge are unfolded and then the protection cover is taken off. The method can be used for the forestation in desert areas with the advantages of improving the micro environment of nursery stock bases, preventing the wind erosion of the soil at the roots of the newly planted seedlings and improving the nursery stock survival rate, has a wide application range and can be widely applied to the construction projects of ecological forests and economic forests.

The invention provides a water-saving high-yield cultivation method for winter wheat. The method comprises the steps of holding water content before planting; optimizing soil preparation; optimizing fertilization; and optimizing irrigation. Compared with a traditional planting mode, the cultivation method has the advantages that one-time irrigation is saved in the later period, so that investment in the whole growth period is not obviously increased, but the yield is relatively high, the water consumption is relatively low, and the whole input-output ratio is the highest. By adopting the cultivation method, good soil fertility and moisture conditions are created for growth of the winter wheat before planting, and the winter wheat is promoted to form enough group and strong seedlings before winter; and a relatively high kernel number per spike is obtained through sufficient fertility supply after a slow-release nitrogen fertilizer is adopted, thereby obtaining the highest yield and input-output ratio. Above all, by adopting the method provided by the invention, 446.5m<3> underground water can be saved for per hectare, the method has positive significance for the Haihe plain which is seriously lack of water, soil wind erosion of a wheat field can be significantly reduced and the average soil erosion intensity is reduced by 69.9% in comparison with a conventional cultivation mode.

The invention discloses a high-cold area winter wheat life limit division and north shift and freezing injury check planting method. According the invention, the phenomenon that the winter wheat seedling emerges from the surface of the earth in corresponding snow cover in high-cold area to realize overwintering green returning is regarded as the winter wheat life limit, and the winter wheat life limit is divided and shifted north, wherein the step of winter wheat division and north shift comprises the division of a planting area and the division of the planting surface down-shift life support interval. The planting area is divided into a safe area, a relatively safe area and a dangerous area; the safe area includes the forest seas and snow rivers under the effect of forest climate; the relatively safe area includes the plains under relatively thick snow cover, depressions and shady slopes of snowfield; and the dangerous area includes the downlands under relatively thin snow cover, slopes exposed to sun and suburbs influenced by the urban greenhouse effect. The planting surface down-shift life support interval is divided into a mechanical tillage interval and a non-mechanical tillage interval. The planting method comprises the following steps of: performing a freezing injury check experiment of the north-shift winter wheat overwintering; determining the planting mode of the winter wheat of the variety by use of corresponding measures; and finally maximizing the north-shift planting area of the high-cold area winter wheat.

The invention discloses preparation of a saline-alkali soil conditioner based on woody plant refining and a using method of the soil conditioner and belongs to the field of soil agrochemistry. The preparation method comprises the following steps: acidizing woody plant residues with sulfuric acid, and performing low-temperature slow destructive distillation to obtain a woody plant source organic acid; and performing neutralizing gypsification on strong acidic woody plant biochar with equivalent quick lime, thereby obtaining the saline-alkali soil conditioner base; uniformly mixing the gypsifiedwoody plant biochar and a to-be-conditioned saline-alkali soil surface, spraying the woody plant source organic acid to promote calcium substitution of sodium ions in soil clay; covering the land with plant straws, inoculating plant lactobacillus to promote acid production, and finally performing alkali leaching with water; and performing drip irrigation and hole sowing of crops in the saline-alkali soil subjected to alkali leaching, performing no-tillage crop rotation, and performing intercropping cultivation. The source of the production materials is very wide and readily available, the cost is low, serious three-waste pollution is avoided in the preparation process, and the saline-alkali soil conditioner is an edged tool of saline-alkali soil improvement and is capable of rapidly obtaining economic and environmental returns.

The invention belongs to the planting method field of rapid restoration of perennial vegetation in a wind sand ground, and discloses a method for quickly planting grass-legume mixed sowing grassland in the wind sand ground of a Mongolia and Liaoning agro-pastoral transition zone. According to the method, the problems of vegetation degradation, grassland productivity decline and low forage grass quality are solved through adding spatial distribution uniformity of Chinese wildrye and an alfalfa, and the seed seeding rate. The method includes the steps that 1, ground is leveled and weeds are cut; 2, seeds are sowed, specifically, the mass radio between the Chinese wildrye and the alfalfa is 7:1, and then the seeds are mixed and then planted in rows by dividing furrows; and 3, administrationand management are conducted, specially, watering is conducted on a seedling stage, and harvesting is conducted before the middle of August. The method of quickly planting the grass-legume mixed sowing grassland in the wind sand ground of the Mongolia and Liaoning agro-pastoral transition zone has the advantages that seedling mucking earth rate, the settlement rate and the resume growth rate are increased, the cost is low, a planting period is short, popularization is easy and the like; and soil fertility can be added, the weeds are controlled, the yield and quality of pastures are increased,and degradation vegetation in the wind sand ground can be recovered quickly.

The invention discloses a green covering production mode of spring wheat-winter rape-vicia sativa, aiming at the low resource utilization rate of the one-year-old cultivation mode in the Northwest Oasis Irrigation District, the continuously depleted crops and the degraded quality. The winter rape is planted after the spring wheat, and vicia sativa is planted after harvesting winter rape, which cannot only make full use of water and heat resources, but improve soil physical and chemical properties to improve its fertility with green manure while great and stable harvest is ensured, thereby achieving planting mode of 'fertile field with field', 'fertile land with land' and 'combination of utility and protection'; besides, the green plants in winter can effectively reduce wind erosion and reduce sandstorms in the northwestern arid regions.

The invention discloses a continuous wing fin bag sand barrier laying machine. The laying machine comprises a machine frame and a sand barrier laying system arranged on the machine frame; the sand barrier laying system comprises a sand taking unit, a bag-making unit, a sand filling unit and a laying unit, wherein the sand taking unit is used for collecting sand particles and placing the collectedsand particles on sand-containing cloth, the bag making unit is used for sewing the sand-containing cloth containing the sand particles to form the wing fin bag, the sand filling unit is used for filling the sand particles into the bag making unit in the bag making process, and the laying unit is used for continuously laying the filled wing fin bag. According to the continuous wing fin bag sand barrier laying machine, sand taking, bag making, sand filling and laying are integrated into one machine, and the continuous sandbag with wing fins is formed; and the wind speed can be remarkably reduced, erosion of the wind power to the ground surface can be reduced, the operation efficiency can be greatly improved, the labor intensity of operators is reduced, the laying quality is good, and the working state is relatively stable after continuous operation.

The invention discloses a no-tillage water replenishing sowing method based on a condition of total straw coverage. In areas of rainfall below 450 mm and in areas of aeolian sandy soil or severe areasof wind erosion, the method includes the following specific steps: after corn enters a stage of complete ripeness, a large-scale corn harvester is employed for harvesting, and corn stalk is simultaneously pulverized and uniformly spread on the earth surface; during suitable sowing time from the last ten days of April to the first ten days of May of the following spring, straw covering the earth surface of sowing rows is cleaned out a sowing zone with the width of 40 cm to reach a to-be-sowed state; sowing, water replenishing, fertilizer application, and pressing are completed once on a cleaned sowing zone by employing a no-tillage water replenishing sowing machine; and after seedlings emerge, a herbicide is sprayed for weeding; and when the corn has 3-4 expansion leaves, soil under corn seedlings is loosened. Compared with the prior art, high-quality sowing can be achieved under the condition that the straw totally covers and is returned to the field, a sufficient water source is provided for seed germination according to a soil moisture state, the quality of a group seedling stage is ensured, and the usage amount of the herbicide is reduced.

The invention discloses a planting method to multiple-crop Vicia villosa after return of spring wheat straws to the field. The planting method includes the steps of (1) seeding spring wheat in the beginning of spring in the very year, and irrigating regularly; (2) after the spring wheat of step (1) is mature, harvesting with high stubbles left, crushing the harvested spring wheat straws, returningto the field, and multiple-cropping Vicia villosa; (3) upon frost season of the very year, reaping Vicia villosa, and returning to the field by covering; (4) repeating the steps (1), (2) and (3) in the next year. The planting method has the advantages that the input of nitrogen fertilizer for wheat cultivation can be decreased, multiple cropping and crop rotation help balance the soil nutrients,the return of the spring wheat straws to the field and the return of Vicia villosa to the field help increase the content of organics and effective nutrients, such as N and P, in the topsoil of a farmland, part of inorganic chemical fertilizer can be replaced, land fertility can be increased, and the return of Vicia villosa to the field helps reduce wind erosion and maintain high water content ofsoil.

The invention discloses preparation of a desertified soil conditioner based on straws and a using method of the desertified soil conditioner. The preparation of the desertified soil conditioner basedon the straws comprises the steps of feeding straw powder in a mixed solvent consisting of ethylene glycol, ethyene catrbonate and sulfuric acid; preparing straw polyols in a liquidation manner underthe conditions of normal pressure and middle temperature; blending the straw polyols with isocyanate at high speed; spraying the mixture to desertified soil applied with a large number of a decomposedorganic fertilizer; meanwhile stirring the sprayed soil by using a rotary stirring machine; placing the stirred agglomerated soil on the surface of the desertified soil; and slightly pressing the desertified soil to form a moisture-retention and fertilizer-retention plough layer which has the thickness of 20 cm and has a porous structure. By the conditioner, the characteristics of dispersed particles and poor moisture and fertilizer retention of the desertified soil are solved, and agglomeration structures, water retention and storage ability and nutrient adsorption functions of the desertified soil are improved effectively. By straw liquid, types and contents of organic matters of the desertified soil are improved, and repair of the desertified soil and development of high-efficiency agriculture and forestry are facilitated.

The invention belongs to the agricultural production machines, and particularly relates to a double-row peanut seeder on a rotary tillage stubble ploughing separated layer fertilization ridge. A rotary cultivator gearbox (20) is fixedly arranged on a front cross beam of a main machine frame (1), and a front fertilizer conveying guide tube (33) below a front fertilizer box (2) is inserted in a rotary cultivator protective cover (12). A bearing seat frame (42) is fixed above an auxiliary machine frame (1-3), and a bearing seat (24) is fixed on the bearing seat frame (42). A seed discharging chain wheel (18) is arranged at the right end of a seed discharging device shaft (44), and land axles (43) are arranged at the positions below the two sides, corresponding to the seed discharging device shaft (44), of the main machine frame (1) by land wheel bearing frames (23). Land wheels (5) are arranged at the two ends of the land axles (43), and a front fertilizer discharging chain wheel (17), a rear fertilizer discharging chain wheel (19), the seed discharging chain wheel (18) and a land wheel chain wheel (16) are in transmission connection by a same chain (15). The double-row peanut seeder on the rotary tillage stubble ploughing separated layer fertilization ridge solves the difficult problem that ridge sealing can not be achieved due to large ridges, and the effect of reducing wind erosion and soil water loss is achieved.

The method for controlling desertification by using artificial tree includes the following steps: 1. preparing artificial tree: using plastics, rubber, nylon or glass fibre reinforced plastics as rawmaterial to prepare artificial tree which is identical to real tree in three form, branches, leaves and colour, and its underground portion root system posseses main root, side root and hair root, its root system has 2-3 layers; 2. planting artificial trees; pit planting or planting in rows; 3. planting natural trees: planting natural arbor species and shrub species in gaps between artificial trees; and 4. taking out artificial trees; when the vegetative cover rate is up to above 50%, taking out artificial trees.

The invention relates to a square seeding method for preventing and removing weeds in an alfalfa field. The method comprises the following steps: (a) selecting a land; (b) ploughing and harrowing; (c)applying an organic fertilizer; (d) preparing the land; (e) irrigating; (f) seeding, sowing alfalfa seeds in line along the north-south direction by using a no-tillage planter, after the seeding in the north-south direction, seeding from the northeast direction to the southwest direction and intersected with a north-south ridge in 90 degrees, until completely finishing the seeding, and (g) fieldmanagement. The method is capable of, through squarely sowing in the alfalfa field, forming a square encirclement formed by the alfalfa, and forming a small independent habitat, effectively reducing the amount of allelopathic chemicals released by the alfalfa which are blown away by the wind on the one hand, thereby the field weeds are inhibited by the alfalfa allelopathic chemicals so that the field weeds are not grown or grown slowly; and on the other hand, because the alfalfa is arranged squarely, so a growing space of the weeds is affected, thereby reducing the space competition probability of the weeds and the alfalfa.