阅读说明：本技术 一种草酸药剂促进还田秸秆光解和生物降解的方法 (Method for promoting photolysis and biodegradation of returned straws by oxalic acid agent ) 是由 蔡喜运 景旭东 柴旭辉 王祎纯 陈景文 刘新刚 于 2019-11-18 设计创作，主要内容包括：本发明属于秸秆生物质资源化利用技术领域,提供了一种草酸药剂促进还田秸秆光解和生物降解的方法。本发明针对还田秸秆分解缓慢的问题,通过外源施加草酸药剂促进还田秸秆光解和生物降解,开展了不同用量的草酸药剂对秸秆光解和生物降解影响的研究,筛选了草酸药剂的最佳用量,同时考查了药剂施加后对土壤pH、脱氢酶活性等的影响,证实了草酸药剂可以在自然光照下破坏秸秆的结晶区域,增加秸秆埋入土壤后分解酶的生物可及性,促进秸秆的降解,这对秸秆还田的推广及应用具有一定的指导意义。(The invention belongs to the technical field of resource utilization of straw biomass and provides a method for promoting photolysis and biodegradation of returned straw by using an oxalic acid agent. Aiming at the problem that the decomposition of the returned straws is slow, the returned straws are promoted to be photolyzed and biodegraded by externally applying oxalic acid agents, the research on the influence of different dosages of oxalic acid agents on the photolysis and the biodegradation of the straws is developed, the optimal dosage of the oxalic acid agents is screened, meanwhile, the influence of the applied agents on the pH value of soil, the dehydrogenase activity and the like is examined, the fact that the oxalic acid agents can damage the crystallization area of the straws under natural illumination is verified, the biological accessibility of the resolvase is increased after the straws are buried in the soil, the degradation of the straws is promoted, and the method has certain guiding significance on the popularization and the application of the returned straws.)

1. A method for promoting photolysis and biodegradation of returned straws by an oxalic acid agent is characterized by comprising the following steps:

(1) performing photolysis treatment on the straws: firstly, preparing an oxalic acid medicament into an oxalic acid solution, and then uniformly spraying the fully dissolved oxalic acid solution on the surface of crushed straws, wherein the particle size of the straws is 1-8cm, and the dosage of the oxalic acid medicament is 0.1-5% of the mass of the straws; the straw subjected to pesticide spraying treatment is naturally illuminated on the soil surface of the outdoor farmland;

(2) biodegradation of straw: weighing the straws obtained in the step (1), then putting the straws into a nylon bag, burying the straws into farmland soil with the depth of 10-20cm according to the straw returning proportion of 300-800kg per mu of field returning amount, and normally managing the rest fields; taking out the straws according to periods after one week of culture, taking the soil remained on the straw nylon bag, and measuring the pH value and the dehydrogenase activity of the soil; and cleaning to remove soil adhered to the surfaces of the straws, drying at 60 degrees, sealing and storing, measuring the quality of the straws, and evaluating the effect of the oxalic acid agent according to the mass residue of the straws.

Technical Field

The invention belongs to the technical field of resource utilization of straw biomass, and particularly relates to a method for promoting field-returning straw photolysis and biodegradation by applying an oxalic acid medicament from an external source.

Background

The straw is mainly composed of macromolecular chains such as cellulose, hemicellulose, lignin and the like, wherein the straw cellulose has a compact crystallization area, can block the biological accessibility of decomposition enzymes, and limits the rapid decomposition of the straw. Particularly in northeast agricultural areas, the straws are returned to the field and then enter a long winter, and the biological decomposition of the straws is limited under cold and cool climatic conditions. Therefore, how to promote the decomposition of the returned straws under the cold and cool climate conditions is an important problem for solving the difficulty of returning the straws to the field.

At present, methods for accelerating straw decomposition mainly focus on externally applying a decomposition microbial inoculum to promote straw biodegradation. Patent CN 107502548A discloses a screening method of low temperature resistant straw degradation strains, patent CN 102559763A discloses a method for promoting complex enzyme to catalyze and degrade straw stalks by using active mediator combination, and patent CN 102535238A discloses a method for catalyzing and degrading straw stalks by using oxalic acid and Mn²⁺A method for promoting compound enzyme to catalyze and degrade rice straws, and a patent CN 102559764A discloses a method for promoting compound enzyme to catalyze and degrade rice straws by utilizing veratryl alcohol and oxalic acid. The methods mainly accelerate the biodegradation of the straws by improving the principle of decomposing the activity of the enzyme, are influenced by indigenous microorganisms and the change of the natural environment of the farmland, the activity of the externally applied biodegradation microbial inoculum or complex enzyme has certain volatility, the results of the laboratory and the field are often greatly different, and the popularization and the application of the method are limited by the application cost of the farmland. The invention utilizes the harvested straws to cover the ground surface, promotes the natural photolysis of the straws at low temperature or normal temperature by spraying oxalic acid medicament, and destroys the compact rigidity of the straw fibersThe structure is adopted, and then after soil is ploughed next year, the biological accessibility of the straw decomposition enzyme is improved, and the biological degradation of the straw is accelerated. The agent can be mixed with common fertilizer, reduces production cost, and has practical popularization significance.

Disclosure of Invention

The invention provides a method for promoting photolysis and biodegradation of returned straws by externally applying an oxalic acid medicament aiming at the problem of slow decomposition of the returned straws. The method screens the optimal proportion and dosage of the agent, simultaneously examines the influence of the agent on soil physical and chemical properties such as soil pH, dehydrogenase activity and the like, confirms that the agent can promote the photolysis of the straws, destroys the compact rigid structure of the straws, accelerates the natural decomposition of the straws from the perspective of chemically strengthening the biodegradation of the straws after the photolysis, and has certain guiding significance for the popularization and the application of straw returning to the field.

The technical scheme of the invention is as follows:

a method for promoting photolysis and biodegradation of returned straws by an oxalic acid agent comprises the following steps:

(1) performing photolysis treatment on the straws: firstly, preparing an oxalic acid medicament into an oxalic acid solution, and then uniformly spraying the fully dissolved oxalic acid solution on the surface of crushed straws, wherein the particle size of the straws is 1-8cm, and the dosage of the oxalic acid medicament is 0.1-5% of the mass of the straws; the straw subjected to pesticide spraying treatment is naturally illuminated on the soil surface of the outdoor farmland;

(2) biodegradation of straw: weighing the straws obtained in the step (1), then putting the straws into a nylon bag, burying the straws into farmland soil with the depth of 10-20cm according to the straw returning proportion of 300-800kg per mu of field returning amount, and normally managing the rest fields; taking out the straws according to periods after one week of culture, taking the soil remained on the straw nylon bag, and measuring the pH value and the dehydrogenase activity of the soil; and cleaning to remove soil adhered to the surfaces of the straws, drying at 60 degrees, sealing and storing, measuring the quality of the straws, and evaluating the effect of the agent according to the mass residue of the straws.

The invention has the beneficial effects that: according to the invention, natural photolysis of the straws is utilized under cold and cool climatic conditions, and the oxalic acid agent is applied from an external source to promote the photolysis of the straws, so that the biodegradation of the straws after being buried in soil is accelerated; the influence of the applied agent on the physicochemical property of the soil is considered, and the optimal dosage of the agent is screened, so that the method has certain guiding significance for popularization and application of straw returning to the field.

Drawings

FIG. 1 effect of agent application on straw natural photolysis.

FIG. 2 shows the effect of different dosages of the agent on the biodegradation of straw.

FIG. 3 shows the effect of long-term chemical on the biodegradation of straw.

FIG. 4 the effect of different agent dosages on soil pH.

FIG. 5 the effect on soil pH under long-term agent action.

FIG. 6 effect of different agent dosages on soil dehydrogenase activity.

Detailed Description

The following further describes a specific embodiment of the present invention with reference to the drawings and technical solutions.