63 results about "Ammonium nitrogen" patented technology

The invention relates to the technical field of agricultural fertilizers, in particular to an enzymolysis fish protein type amino acid-containing water-soluble fertilizer and a preparation method thereof, the fertilizer is prepared from 50-70% of enzymolysis fish protein stock solution and other components; the stock solution is prepared by pulping aquatic product processing leftovers, adjusting the pH value to 6.5-7.5, adding specific compound protease for enzymolysis, and performing enzyme deactivation and centrifugation; the macroelement liquid contains nitrate nitrogen and ammonium nitrogen (2: 1-4: 1), and the microelement chelating agent is prepared by reacting a stock solution small molecule peptide with a specific salt. The fish protein enzymolysis stock solution is prepared from aquatic product processing leftovers, high-proportion small molecule peptide and amino acid are obtained through specific enzymolysis and other processes, and by matching with high-content macroelements in a specific nitrogen form, nutrition can be rapidly supplemented, and crop photosynthesis and dry matter accumulation can be improved; and moreover, all the components cooperate to regulate the growth of the crops and improve the stress resistance, and the surfactant also improves the utilization rate of the fertilizer and reduces waste.

This invention discloses a slow-release fertilizer suitable for lateritic soils in Hainan, comprising a fertilizer core and a coating layer; the fertilizer core comprises the following raw materials in parts by weight: 10-20 parts isobutylene diurea, 1-3 parts 3,4-dimethyl-1H-pyrazole dihydrogen phosphate, 1-3 parts dicyandiamide DCD, 20-30 parts humic acid, and 30-50 parts organic fertilizer; the coating layer comprises the following raw materials in parts by weight: 5-10 parts natural nanotube halloysite, 3-5 parts bentonite, 5-10 parts cyclodextrin, 1-3 parts polyglutamic acid, 1-3 parts wood vinegar, and 5-10 parts polyacrylamide. The isobutylene diurea, humic acid, and organic fertilizer of this invention can effectively replenish organic matter and nitrogen in iron-aluminate soil, maintain soil nitrogen levels, and effectively control the conversion of ammonium nitrogen to nitrate nitrogen in lateritic soil, thereby reducing nitrogen loss and achieving a stable supply of nitrogen. In addition, polyglutamic acid and polyacrylamide have strong water retention capacity, and the fertilizer core is coated with a coating layer to achieve slow release and water retention.

The invention belongs to the technical field of pathogenic bacterium wastewater treatment, and particularly relates to a method capable of effectively and synergistically removing ammonia nitrogen and pathogenic bacteria in wastewater. According to the method, in a water body in which ammonia nitrogen and pathogenic bacteria coexist, the two pollutants are removed at the same time by utilizing the oxidation-sterilization synergistic effect of Fe (VI) / PAA. Pollutant ammonium nitrogen in the oxidation system serves as a resource to participate in removal of pathogenic bacteria, the existence of ammonium nitrogen promotes generation of intermediate oxidation products Fe (IV) and Fe (V) of potassium ferrate, then the oxidation inactivation capacity of the system is enhanced, the inactivation time of the pathogenic bacteria in wastewater is effectively shortened, meanwhile, nitrogen is converted into nitrogen, nitrate and the like, the removal rate of NH4 < + > within 30 min reaches 98.6%, and the removal rate of potassium ferrate reaches 98.6%. The total nitrogen removal rate reaches 97.2%, pathogenic bacteria inactivation and ammonium salt removal are carried out at the same time, and a new thought and technology are provided for removing pathogenic bacteria and ammonium salt in water treatment.

This invention belongs to the field of fertilizer additive technology, specifically relating to a Cu-containing additive. Ⅱ The coordination polymers, preparation methods, and applications are described. The preparation methods include: synthesizing N,N'-bis(3-pyridinecarboxamide)-1,2-ethane using nicotinic acid and 1,2-ethylenediamine as raw materials; and synthesizing Cu-containing polymers from N,N'-bis(3-pyridinecarboxamide)-1,2-ethane, CuCl2·2H2O, and 1,4-cyclohexane using a hydrothermal method. Ⅱ The coordination polymer [Cu(1,4-chdc)(3-dpye)]·3H2O is a blue crystal. The product prepared in this invention is used as a fertilizer additive in urea to reduce the conversion of urea N to ammonium nitrogen and ammonium nitrogen to nitrate nitrogen during urea application, thereby reducing the volatilization of NH3 into the air after urea application and the subsequent volatilization of N2O.

The invention relates to the technical field of agricultural resources and environment, in particular to a fertilization method for reducing nitrogen loss of an apple orchard. The apple branch biochar is prepared from the apple orchard pruning waste, and resource utilization of the waste is achieved. Through the synergistic effect of the apple branch charcoal, dicyandiamide and the reduced nitrogen fertilizer, the loss of nitrate nitrogen in soil is obviously slowed down, the conversion of ammonium nitrogen is inhibited, and a nitrogen cycle functional microflora is regulated, so that the application amount of the nitrogen fertilizer is reduced, the utilization rate of the nitrogen fertilizer is improved, and the environmental pollution is reduced; the growth of apple plants can be obviously promoted, the root configuration is improved, and the root activity and the nitrate reductase activity are improved.

The application discloses a method for promoting early flowering of strawberries, and belongs to the technical field of cultivation. The method uses exogenous H2O2 to achieve the effects of promoting flower bud differentiation and promoting roots. First, 10 days before planting of the strawberries, H2O2 solution is sprayed on the whole plant, with a concentration of 5 mmol / L, and the spraying is continuously carried out for 10 days, with the leaf buds being mainly sprayed; then, after the seedlings are successfully recovered, one piece of new root-promoting prescription (brown sugar+H2O2+paenibacillus polymyxa) is placed beside each seedling; finally, after the seedlings are recovered, 15 mmol / L ammonium nitrogen fertilizer is flushed and applied for 2-3 times. The method can effectively promote early flower bud differentiation of the strawberries at low cost, and can achieve the effects of root protection and root promotion.

The invention aims to provide a method for increasing soil fertility and measuring ammonium nitrogen of the soil. The method for increasing the soil fertility comprises the step of adding the microbial agent into the soil to prepare the composite microbial agent for repairing the saline-alkali soil and improving the soil fertility, and the composite microbial agent adapts to various types of soil, so that organic matters of the soil are increased, available nitrogen, phosphorus and rapidly available potassium are remarkably increased, the salinity and alkalinity are effectively reduced, and the soil fertility is improved. Meanwhile, the invention provides a soil ammonium nitrogen measuring method which is efficient, visual, low in cost and capable of measuring on site.

The present application relates to a kind of by chrysophyte fermentation-light coupling high-efficiency production of fucoxanthin method, comprising: chrysophyte is inoculated into fermenter and is carried out heterotrophic culture, while the algal liquid is continuously or intermittently lighted;Culture medium includes basic medium and feed medium, C / N is 4:1-40:1, nitrogen source uses organic nitrogen source or inorganic ammonium nitrogen;The glucose concentration in basic medium is 5-15g / L, temperature is 25-32℃, dissolved oxygen is controlled at 5-80%, pH is 4-8, light intensity 5-600 μmol m ‑2 s ‑1 ;Glucose concentration is monitored in time during the cultivation process, when glucose concentration is reduced to 0.5-3g / L, using peristaltic pump to flow feed medium is added to flow culture, control the glucose concentration in whole flow culture process in 1-10g / L;After 100h of cultivation, every 1-5h is sampled to detect the biomass dry weight contained in the culture medium in fermenter, when the detection value is unchanged or begins to drop, fermentation is finished, harvest, and the harvested product is used for extracting fucoxanthin.The present application establishes the feasibility basis of fermentation-light coupling chrysophyte cultivation to scale production of fucoxanthin.

The invention belongs to the technical field of fertilizer additives, and particularly relates to a CuII-containing coordination polymer and a preparation method and application thereof.The preparation method comprises the steps that N, N '-bis (3-pyridinecarboxamide)-1, 2-ethane is synthesized with nicotinic acid and 1, 2-ethylenediamine as raw materials; the preparation method comprises the following steps: synthesizing a coordination polymer [Cu (1, 4-chdc) (3-dpye)]. 3H2O containing Cu II from N, N '-bis (3-pyridinecarboxamide)-1, 2-ethane, CuCl2. 2H2O and 1, 4-cycloadipic acid by using a hydrothermal method, so as to obtain a blue crystal. The product prepared by the invention is applied to urea as a fertilizer additive, so that the conversion of urea N to ammonium nitrogen and the conversion of ammonium nitrogen to nitrate nitrogen in the urea application process are reduced, and the volatilization of NH3 in the air and the subsequent volatilization of N2O after the urea is applied are reduced.

An aeration tank and a sewage treatment system are characterized in that an anoxic regulation and control mechanism and an aerobic regulation and control mechanism are arranged in an aeration tank body, the anoxic regulation and control mechanism can create an anoxic environment around the anoxic regulation and control mechanism so that the area becomes an anoxic section, and the aerobic regulation and control mechanism creates an aerobic environment around the aerobic regulation and control mechanism so that the area forms an aerobic section; in the process that sewage flows along the channel, the sewage sequentially passes through the anoxic zone and the aerobic zone, in the anoxic zone, most nitrate radicals and nitrite radicals in the sewage are reduced into nitrogen by denitrifying bacteria in activated sludge, and nitrogen elements in the sewage are removed; in the aerobic section, most ammonium nitrogen in the sewage is converted into nitrate and nitrite by nitrifying bacteria in the activated sludge, and nitrogen in the sewage is further converted and removed; the denitrification effect of the anoxic section and the nitrification effect of the aerobic section are synergistically carried out, so that nitrogen elements in sewage can be more effectively removed, the denitrification efficiency is greatly improved, up-to-standard discharge of the sewage is ensured, and eutrophication pollution to a water body is reduced.

This invention belongs to the field of crop breeding, specifically relating to an NtLHT1 gene and its application in tobacco's resistance to low nitrogen stress. It involves artificially intervening in the mutation of specific nucleotide sequence fragments in the NtLHT1 gene to obtain two mutated nucleotide sequence fragments, resulting in a mutant NtLHT1 gene, and the application of the mutant NtLHT1 gene in improving tobacco's resistance to low nitrogen stress. The NtLHT1-edited tobacco plants of this invention exhibit enhanced absorption of nitrate and ammonium nitrogen during their vigorous growth period, increased activity of nitrate reductase and glutamine synthase, increased expression of nitrogen transporter genes, and improved nitrogen utilization efficiency. This invention increases the activity of nitrate reductase and glutamine synthase, thereby improving tobacco's resistance to low nitrogen stress and providing a genetic resource and material basis for the development of nitrogen utilization-related genes and strains in tobacco.

The invention discloses a preparation method of a NiII-containing coordination polymer and research on the inhibition effect of the NiII-containing coordination polymer on soil urease and nitrifying bacteria, and the preparation method comprises the following steps: synthesizing N, N-dimethylformamide by taking pyridine-3-carboxylic acid and 1, 2-ethylenediamine as raw materials; the invention discloses a novel coordination polymer [Ni (1, 4-chdc) (3-dpy) (H2O) 2], which is prepared by the following steps of: synthesizing N, N '-bis (3-pyridinecarboxamide)-1, 2-ethane by using NiCl2. 2H2O, the synthesized N, N'-bis (3-pyridinecarboxamide)-1, 2-ethane and 1, 4-cycloadipic acid through a hydrothermal method, and researching the influence of the novel coordination polymer [Ni (1, 4-chdc) (3-dpy) (H2O) 2] as an inhibitor on soil urease and nitrifying bacteria by analyzing the crystal structure of the novel coordination polymer [Ni (1, 4-chdc) (3-dpy) (H2O) 2]. The research on the compound as an inhibitor reduces the conversion of urea from urea N to ammonium nitrogen and the conversion of ammonium nitrogen to nitrate nitrogen, improves the utilization rate of the fertilizer urea and the stability of the urea, reduces environmental pollution and improves the grain yield. Compared with a traditional inhibitor, the novel NiII coordination polymer serving as a urease and nitrification inhibitor has the advantages of longer half-life period, small toxic and side effects, low preparation cost and more comprehensive functions, the utilization rate of nitrogen fertilizer urea can be greatly increased, the grain yield is increased, and the environmental pollution is reduced.

This application relates to a method and its application for reducing nitrate nitrogen to ammonia nitrogen in wastewater using a dual-bacterial inoculant. The method involves separately expanding, washing, and resuspending electron-donating bacteria and dissimilatory nitrate-reducing ammonium-producing bacteria, then mixing them in a co-culture medium to form a dual-bacterial inoculant; introducing the co-culture medium containing the dual-bacterial inoculant into the wastewater to be treated, and reducing nitrate nitrogen to ammonia nitrogen in the wastewater under anaerobic conditions. This method can reduce nitrate nitrogen in wastewater into a high-energy-density energy storage substance, and can also alleviate the problems of low utilization rate of ammonium nitrogen fertilizer and non-point source pollution, which is of great value for nitrogen pollution control and green sustainable agricultural development.

The invention discloses an activating agent capable of being used for improving the nitrogen fixation activity of farmland soil in situ and a preparation method of the activating agent, and relates to the technical field of agricultural chemistry. The activating agent is prepared from the biochar, the sodium molybdate, the goethite and the rutile as raw materials and is used for improving the nitrogen fixation activity of the farmland soil in situ. On the premise of not adding exogenous strains, by activating existing indigenous nitrogen-fixing microbial communities in farmland soil and stimulating high-efficiency expression of related nitrogen-fixing functional genes in a soil environment, in-situ activation of the nitrogen-fixing potential of the soil is achieved, and the nitrogen-fixing performance of the soil is improved. The activator for in-situ improvement of the nitrogen fixation activity of the farmland soil has a synergistic effect on improving the content of ammonium nitrogen in the soil and the activity of nitrogenase, has the outstanding advantages of high in-situ adaptability, precise action targeting, sustained and lasting nutrition release, environment friendliness, low cost and the like, can remarkably reduce the use of chemical fertilizers, and has a good application prospect. And sustainable development of green agriculture is realized.

The application relates to the technical field of plant breeding, and particularly relates to application of an SLR1 protein mutant or a coding gene thereof in regulating population yield and harvest index of plants. The SLR1 protein mutant is obtained by mutating at least one of tyrosines at positions 94 and 580 into alanine on the basis of a wild-type SLR1 protein. The application comprises the following steps: improving the function of the SLR1 protein mutant or the expression level of a coding gene thereof for the plants, and improving the plant type, lodging resistance, yield or harvest index of the plants. A SLR1 protein (a member of the DELLA protein family) mutant is obtained through the research of the application, and when the SLR1 protein in the plants is mutated, a semi-dwarf plant type can be obtained, the ammonium nitrogen utilization rate, the nitrate nitrogen utilization rate and the biomass are not greatly affected, the yield and the harvest index are significantly improved, and the application is superior to an sd1 green revolution variety, which has important application value in the field of plant breeding.

The invention discloses bacillus mucilaginosus JZ-235 as well as a preparation method, a microbial agent and application thereof, the preservation number of the bacillus mucilaginosus JZ-235 is CGMCC No.32962, the bacillus mucilaginosus JZ-235 has the advantages of high yield of urease and indoleacetic acid, efficient utilization of ammonium nitrogen and no denitrification effect, crop growth can be remarkably promoted, the yield is increased, CO3 < 2-> is generated while nitrogen (NH4 < + >) is provided for crops, and the bacillus mucilaginosus JZ-235 has the advantages of high yield of urease and indoleacetic acid and no denitrification effect. According to the present invention, with the application of the nitrogen fertilizer, the nitrogen fertilizer efficiency can be easily improved, the influence of the ammonia emission on the environment can be reduced, the nitrogen fertilizer efficiency can be easily improved through the growth and the propagation at the crop rhizosphere, the ratio of the non-denitrification functional bacteria in the soil can be increased, the soil denitrification effect can be reduced, and the nitrogen fertilizer efficiency can be improved; therefore, emission of nitrous oxide is reduced, and environmental protection is facilitated.

The application belongs to the technical field of rice cultivation and relates to a plant factory cultivation method for shortening the growth period of rice based on carbon and nitrogen nutrition regulation. In view of the technical problem that the existing plant factory rice cultivation method has a long growth period and is difficult to meet the rapid cultivation demand, the method comprises seed soaking, germination, seedling raising, post-transplanting management and harvesting, and the core is to transplant rice seedlings to a plant factory water culture system, and synchronous control of cultivation conditions is used to promote early flowering: maintaining CO2 concentration of 400-1600 ppm, using full-spectrum artificial light source, using basic nutrient solution with total nitrogen of 1.2-3.2 mM, molar ratio of ammonium nitrogen to nitrate nitrogen of 2:1-4:1 and pH of 5.5-6.5, and adding L-carnitine and aconitic acid metabolism promoters with a molar ratio of 1.2:1-2.2:1 at the tillering peak stage. The method is mainly used for rapid cultivation of rice in a plant factory, and the cultivation efficiency is improved by shortening the growth period.

The invention relates to the technical field of agricultural management, in particular to a management system for regulating and controlling efficient utilization of farmland soil nitrogen based on nitrifying flora, which comprises a soil multi-source information monitoring module, a nitrifying flora activity evaluation module, a nitrogen conversion path analysis module, a precise regulation and control strategy generation module and a field intelligent execution module. By arranging a multi-parameter sensor array and a nutrient tachymeter, soil nitrogen and environmental factor data are collected and standardized in real time; quantifying the activity of the nitrifying flora based on the coupling model, and predicting the ammonium nitrogen conversion trend in combination with a kinetic equation; a nutrient supply and demand comparison mechanism is constructed, and meteorological and farming information is fused to generate a multi-factor precise fertilization scheme; and finally, the variable fertilizer applicator is driven to perform quantitative, timed and fixed-depth operation, and the fertilizer application quality is monitored in a closed-loop manner. According to the invention, accurate nitrogen conversion modeling, nutrient balance regulation and control and intelligent equipment linkage are realized, and support is provided for improving the nitrogen fertilizer utilization rate and green agriculture.

The invention discloses a method for recovering ammonium and nitrogen from ardealite leachate and co-producing magnesium fluoride, which comprises the following steps: uniformly mixing the ardealite leachate and magnesium salt, then adding first ethanol, adjusting the pH value to be less than or equal to 2.5, and carrying out first stirring reaction and first solid-liquid separation to obtain a solid mixture; washing the solid mixture with water until the pH value is 6-7, and carrying out second solid-liquid separation to obtain magnesium fluoride solid and crude magnesium ammonium sulfate filtrate; and uniformly mixing the crude magnesium ammonium sulfate filtrate with second ethanol, adjusting the pH value to be less than or equal to 2.5, and carrying out second stirring reaction and third solid-liquid separation to obtain a magnesium ammonium sulfate solid. According to the composition characteristics of the ardealite leachate, ammonium nitrogen, fluorine ions, sulfate ions and magnesium salt in the ardealite leachate are directly utilized to react under an acidic condition to generate magnesium ammonium sulfate and magnesium fluoride; the method has the characteristics of simple process, strong adaptability, convenience in operation, mild reaction conditions, low treatment cost, high recovery rate of valuable components, high added value of products and the like.

The present application relates to a kind of CO2 aeration enhanced deep ultraviolet synchronous denitrification and deamination method, specifically related to in the wastewater containing certain concentration nitrate nitrogen and ammonium nitrogen, moderate exposure CO2 gas, accompanied by deep ultraviolet radiation, produce a large amount of CO2 And carbonate radical, electron of ammonium nitrogen is taken to reduce nitrate nitrogen, realize the purpose of synchronous reduction of nitrate nitrogen and ammonium nitrogen.The present application innovatively combines deep ultraviolet photolysis technology and CO2 aeration selective radical generation reaction, and simultaneously utilizes the acidification effect of CO2 on water body to inhibit the stripping effect of ammonium nitrogen, effectively guarantees the sufficient supply of electron donor, realizes the efficient synchronous removal of nitrate nitrogen and ammonia nitrogen.The present application has important significance for controlling water body eutrophication and improving aquatic ecological environment.

The application provides a plant straw-converted liquid fertilizer synergist and a preparation method thereof. The ordinary straw is used as a reaction raw material, so that the source is wide and the price is low. The straw is decomposed through treatment, phosphoric acid groups are introduced, polysaccharides are decomposed into oligosaccharides, and a variety of strains are compounded to form the fertilizer synergist. The fertilizer synergist can form stable complex with ammonium nitrogen and metal cations, reduce the rapid loss of nitrogen, selectively promote the reproduction of beneficial microbial communities, regulate the rhizosphere micro-ecological balance, enhance the functions of nitrogen fixation, phosphorus and potassium dissolution and the like, and realize biological synergism. Overall, through multiple ways of'slow release + growth promotion + soil improvement', the fertilizer synergist provided by the application forms synergistic and long-acting effects in the aspects of fertilizer utilization rate, crop growth promotion and soil improvement.

The present disclosure relates to a method for preparing lysine, which monitors ammonium nitrogen and pH in a culture medium in real time, and introduces carbon dioxide and / or a nitrogen source accordingly, thereby significantly increasing the concentration of lysine while reducing the concentration of by-products, and improving fermentation purity and enhancing the quality of lysine particles.

The invention discloses an ammonium-nitrogen formula compound fertilizer for moso bamboos as well as a preparation method and application thereof. The ammonium-nitrogen formula compound fertilizer comprises a nitrogen source, a phosphorus pentoxide source, a potassium oxide source and a nitrification inhibitor. The invention provides an ammonium nitrogen source preferentially absorbed by moso bamboo, obviously prolongs the retention time of ammonium nitrogen, and promotes biomass accumulation and yield increase of moso bamboo; the form of the liquid fertilizer is combined with double-pot irrigation, bamboo cavity injection or PVP pipe deep application, nutrients can directly reach bamboo roots or bodies, the fertilizer utilization rate is greatly increased, nutrient loss is reduced, the problem of fertilization on rugged terrains is solved, meanwhile, bamboo rhizome floating is reduced, the fertilizer efficiency is prolonged, environment pollution is reduced, and requirements are accurately met. When the compound fertilizer is applied to adult bamboo forests, the fine root biomass is increased by 35.4%, the bamboo shoot emergence rate is increased to 39%, meanwhile, the fertilization frequency and the nitrogen fertilizer dosage are reduced, and collaborative optimization of the moso bamboo yield and ecological environment protection is achieved.

The invention belongs to the technical field of organic fertilizers, discloses a resource utilization method of compost leachate, and solves the technical problem that nitrogen in the compost leachate is not fully utilized in the prior art. The resource utilization method of the compost leachate comprises the following steps: step A, adding organic nitrogen mineralization promoting compound bacteria into the compost leachate, and carrying out aerobic reaction to decompose organic nitrogen to obtain aerobic reaction liquid; step B, adding anaerobic myxobacteria into the aerobic reaction liquid for anaerobic reaction to convert nitrate nitrogen into ammonium nitrogen, so as to obtain anaerobic reaction liquid; step C, adding citric acid-ferrous modified charcoal into the anaerobic reaction liquid to adsorb ammonium nitrogen, and filtering to obtain ammonium nitrogen loaded charcoal; step D, desorbing the ammonium nitrogen loaded charcoal by using a NaCl solution, and collecting a release solution and desorbed charcoal; and step E, carrying out concentration and crystallization treatment on the release liquid to obtain ammonium chloride crystals.

The invention provides a novel bacteriophage of soil denitrifying bacteria and application thereof, and belongs to the technical field of microorganisms. The novel bacteriophage is a bacillus cereus bacteriophage, is named as PHBA67-J and belongs to a tailed bacteriophage, the genome of the novel bacteriophage is double-stranded linear DNA, the full length is 42 and 152 bp, and the GC content is 34.86%. An original enrichment solution of the bacteriophage PHBA67-J is diluted with an SM buffer solution to prepare a bacteriophage suspension with the activity of 1.0 * 10 < 13 > PFU.mL <-1 >, and after 10% (v / w) of active PHBA67-J bacteriophage suspension is inoculated and cultured in darkness for 14 days, the denitrification potential of soil can be remarkably reduced, the content of ammonium nitrogen and nitrate nitrogen in the soil can be remarkably increased, and the nitrogen utilization rate of farmland soil can be improved.

The application relates to a Cu II Preparation method of coordination polymer urease inhibitor, and relates to a preparation method of a urease inhibitor suitable for a fertilizer, 5-hydroxy-N 1 , N 3 -bis (pyridine-3-yl) isophthalamide is synthesized from 5-hydroxy isophthalic acid and 3-aminopyridine as raw materials, and then the coordination polymer is synthesized into a copper-based urease inhibitor by using 1.3.5-benzene tricarboxylic acid as a ligand through a hydrothermal method. Through analysis of the crystal structure and the urease inhibition experiment, the coordination polymer is used as a urease inhibitor to inhibit the urease activity, is added into the fertilizer as an inhibitor, reduces the conversion rate of urea to ammonium nitrogen in the soil in the agricultural fertilization process, improves the fertilizer utilization rate, and reduces the loss of nitrogen elements in the nitrogen fertilizer. The coordination polymer of Cu Ⅱ is a urease inhibitor, delays the hydrolysis of urea into ammonia gas, makes the ammonium nitrogen remain in the soil for a long time, and further improves the utilization rate of the fertilizer.

The invention discloses a method for evaluating compost maturity by using seedling cotyledon changes. The method comprises the following steps: S1, sowing crop seeds in a compost water extract for culture; s2, acquiring the relative chlorophyll content of cotyledons of the crops according to the growth condition of the crop seeds in the culture process in the step S1; and S3, evaluating the compost maturity by taking the relative chlorophyll content of the crop cotyledons obtained in the step S2 as an index. According to the method, the compost maturity is rapidly evaluated by using the sensitivity of crops to plant toxic substances in the early growth stage and taking the relative chlorophyll content of seedling cotyledons as an index, and the evaluation method has high consistency with a traditional evaluation conclusion by using the soluble organic carbon content and the ammonium nitrogen content; the accuracy of the method is verified, more importantly, compared with the known evaluation indexes RSG, RRG and GI of the seed germination test, the conclusion obtained by the method is more strict and comprehensive, and the method has the advantages of short test period, simplicity in operation and low cost.

The invention discloses citrobacter fabricius and application of the citrobacter fabricius in improvement of compost fertilizer efficiency of tung tree fruits, the citrobacter fabricius CDC 2991-81 has been preserved in Guangdong Microbial Culture Collection Center on September 29, 2025, the preservation number is GDMCC No: 67054, and the classification number is citrobacter fabricius (Citrobacter fabricius). By adding the citrobacter fabricius into the tung tree fruit compost, the content of fatty acid in the tung tree fruit compost can be remarkably reduced, the content of ammonium nitrogen, nitrate nitrogen, phosphorus and potassium is increased, and the composting effect of tung tree fruits is remarkably improved. The invention provides a new microbial approach for the utilization of tung tree fruit compost.

The invention belongs to the technical field of organic fertilizers, and particularly relates to an organic stable fertilizer for rice as well as a preparation method and application thereof. The organic stable fertilizer for rice is obtained by taking the modified biomass charcoal as a carrier, loading a tannic acid double-effect inhibitor and combining with a composite organic carbon source. Wherein the modified biomass charcoal is used for stably loading and slowly releasing the inhibitor through physical adsorption and weak hydrogen-bond interaction, and meanwhile, carboxyl on the surface of the modified biomass charcoal can be reversibly combined with soil ammonium nitrogen to realize nitrogen fixation; the tannic acid double-effect inhibitor can achieve double-effect inhibition of urease and nitration through coordination complexation, ammonia volatilization and nitrate nitrogen leaching loss are reduced, and the tannic acid double-effect inhibitor can be naturally degraded without residues; besides, the composite organic carbon source is obtained by compounding lignite humic acid, alkali lignin and rice straw powder, a gradient carbon supply mode is formed by virtue of degradation rate differences of the lignite humic acid, the alkali lignin and the rice straw powder, the carbon supply requirements of the rice in the tillering stage, the booting stage and the pustulation stage are met respectively, the nitrogen utilization rate is effectively improved, the nitrogen supply period is prolonged, and environment friendliness and large-scale cultivation suitability are both considered.

The application discloses a soil heavy metal pollution prevention and treatment device, which comprises a treatment element for injecting a solution into soil, the treatment element comprises an outer shell body, a core shaft is fixedly arranged in the center of the outer shell body, a regulating shaft is slidably arranged at the upper end of the outer shell body, and a down shaft is slidably arranged at the lower end of the outer shell body, a flow guide channel for guiding the flow of the solution is arranged in the core shaft, the regulating shaft can be switched between a connection state and a flow blocking state, when the regulating shaft is switched to the flow blocking state, the flow guide channel is disconnected with a storage cavity between the regulating shaft and the down shaft, and a flow guide interval is arranged between the down shaft and the core shaft and always keeps connected with the storage cavity. The device can freely irrigate the chelating agent in deep soil and shallow soil, and can also loosen the soil when irrigating the chelating agent. The chelating agent used in the application is a natural small-molecule organic acid chelating agent, which can be naturally degraded, improve the soil and increase the content of ammonium nitrogen and potassium in the soil.