阅读说明：本技术 一种生物降解地膜在有机肥水稻栽培上的田间评价方法 (Method for evaluating biodegradable mulching film in field of organic fertilizer rice cultivation ) 是由 沈峥 张亚雷 宋欣 陈磊 李林茹 于 2021-07-23 设计创作，主要内容包括：本发明提供一种生物降解地膜在有机肥水稻栽培上的田间评价方法,所述方法为两无化水稻栽培方法,所述两无化水稻栽培方法为在水稻田的种植过程中不采用农药、化肥,仅使用有机肥的水稻栽培方法,通过定期观察记录,以土壤有机质含量、稻田杂草防治率、水稻产量以及暴露于地表的薄膜破碎程度、地膜官能团变化及相对分子量变化为评价指标,对生物降解地膜在两无化水稻栽培上的降解程度及其影响进行综合评价；以土壤有机质含量、稻田杂草防治率、水稻产量以及暴露于地表的薄膜破碎程度、地膜官能团变化及相对分子量变化为评价指标。本发明中生物降解地膜在两无化水稻中的降解性能的评价指标充分考虑了生物降解地膜的降解机理,全面直观,可理解性强。(The invention provides a field evaluation method of a biodegradable mulch film on organic fertilizer rice cultivation, which is a two-innoxious rice cultivation method, wherein the two-innoxious rice cultivation method is a rice cultivation method only using an organic fertilizer without adopting pesticides and chemical fertilizers in the planting process of a rice field, and the degradation degree and the influence of the biodegradable mulch film on the two-innoxious rice cultivation are comprehensively evaluated by changing the evaluation indexes of soil organic matter content, the weed control rate of the rice field, the rice yield, the degree of film breakage exposed to the ground surface, the change of mulch film functional groups and the relative molecular weight through regular observation and recording; the evaluation indexes are the organic matter content of soil, the weed control rate of a rice field, the rice yield, the degree of film breakage exposed on the ground surface, the change of functional groups of the mulching film and the relative molecular weight. The evaluation index of the degradation performance of the biodegradable mulching film in the two types of innocent rice fully considers the degradation mechanism of the biodegradable mulching film, and the biodegradable mulching film is comprehensive, visual and strong in intelligibility.)

1. A field evaluation method of biodegradable mulch film on organic fertilizer rice cultivation is a two-non-chemical rice cultivation method, wherein the two-non-chemical rice cultivation method is a rice cultivation method which does not adopt pesticides and fertilizers in the planting process of a rice field and only uses organic fertilizers, and is characterized by comprising the following steps:

s1: the organic matter content of soil, the weed control rate of a paddy field, the rice yield, the fragmentation degree of a biodegradable mulching film exposed on the ground surface, the functional group change and the relative molecular weight of the mulching film are used as evaluation indexes;

the weed control rate of the rice field is (the number of the weeds in the rice field without film covering-the number of the weeds in the rice field with film covering)/the number of the weeds in the rice field without film covering is 100 percent;

s2: arranging test cells with equal areas in the investigation region far away from the edge region, and adopting mechanical seedling transplanting and film mulching planting, wherein the transplanting density is 30cm multiplied by 12cm, and 7.5-8 w of basic seedlings per mu; observing and recording the mechanical damage condition of the mulching film in the laying process; observing and recording the damage degree of a mulching film exposed on the ground surface every 15 days after the rice is mechanically covered with the film, and collecting soil by adopting a quincunx point sampling method to detect the content of organic matters; collecting mulch film samples every 45 days to analyze the change of the functional groups and the relative molecular weight; meanwhile, observing the growth condition of weeds in the rice field;

s3: after the rice is harvested, the weed control rate and the rice yield of the rice field are counted, the degradation degree of the mulching film, the change of the functional group of the mulching film and the relation between the relative molecular weight change and time are analyzed, and a corresponding chart is drawn.

2. The field evaluation method of biodegradable mulch film on organic fertilizer rice cultivation as claimed in claim 1, wherein in step S1, the damage degree of the biodegradable mulch film is graded by 0-5, and the grade of the degradation performance of the biodegradable mulch film is represented by the number size: 0 is that the mulching film is kept complete and is not damaged; 1, a tiny crack of 0-2 cm naturally appears at the beginning of the mulching film; 2, a 2-20 cm crack appears on the mulching film; 3, the mulching film has large cracks of 20-50 cm and the number of the cracks is increased; 4, the mulching film is uniformly cracked and decomposed into a plurality of small pieces, and no large mulching film exists on the soil surface; and 5, the mulching film on the soil surface basically disappears or only slightly remains.

3. The field evaluation method for the biodegradable mulch film in the organic fertilizer rice cultivation as claimed in claim 1, wherein when the organic matter content of the soil is detected in step S2, a plum blossom point sampling method is adopted to collect soil samples of 0-20 cm soil in each test cell, and the organic matter content of the soil is detected.

4. The field evaluation method of biodegradable mulch film for organic fertilizer rice cultivation as claimed in claim 1, wherein when analyzing the change of mulch film functional groups in step S2, mulch film samples are collected in each test cell, and fourier infrared spectroscopy is used for detection and analysis, wherein the measurement range is 500-4000 cm^-1。

5. The field evaluation method of biodegradable mulch film on organic fertilizer rice cultivation as claimed in claim 1, wherein the change of mulch film relative molecular weight in step S2, mulch film samples were collected in each test cell and analyzed by gel chromatograph with sample injection volume of 10.00 μ L for 15.00 min.

6. The field evaluation method for the biodegradable mulch film in the organic fertilizer rice cultivation as claimed in claim 1, wherein in the step S2, when test cells with equal area are laid in the inspected plot far from the edge area, the number of the inspected test cells is not less than 5.

7. The field evaluation method for the cultivation of organic fertilizer rice with the biodegradable mulching film according to claim 1, wherein in the step S2, the planting density of the mechanical seedling planting mulching film planting is 30cm x 12cm, and the basic seedlings per mu are 7.5-8 w.

Technical Field

The invention relates to a field evaluation method of a biodegradable mulching film in organic fertilizer rice cultivation, in particular to a field evaluation method of a biodegradable mulching film applied to two-stage non-biochemical rice cultivation, and belongs to the field of farmland ecological environment protection.

Background

In the crop planting process, the use of pesticides and chemical fertilizers brings huge threats and challenges to the farmland environment, and the application of pesticides and chemical fertilizers deviates from the construction and development targets of green ecological organic agriculture. The 'double-innocent' rice means that no chemical pesticide or chemical fertilizer is used in the rice planting process, the scientifically preferred organic fertilizer is applied to replace the chemical fertilizer, the problem of providing nutrients required by normal growth of the rice is solved, and the fact that no pesticide is used means that a large amount of weeds are bred in a rice field to seriously affect the growth of the rice, so weeding becomes a key problem to be solved in the 'double-innocent' rice planting. Although the traditional artificial weeding is simple and convenient to operate and can effectively prevent weeds from breeding, a large amount of manpower and financial resources are consumed, and the traditional artificial weeding is not an ideal weeding mode under the situation that the aging problem is increasingly serious. In recent years, the technology of the biodegradable plastic film mulching planting special for rice is rising and gradually develops and matures. The biodegradable plastic film is adopted for covering in the 'two-crop' rice planting, so that the rice field mulching film is convenient to use, water-saving and fertilizer-preserving, time-saving and labor-saving, and can effectively prevent and control the breeding of weeds in the rice field. Meanwhile, the biodegradable mulching film made of the full-biodegradable plastic is degraded under the action of microorganisms in the nature or in specific conditions, and finally is completely decomposed into carbon dioxide, methane, water, inorganic salt and the like, so that the recovery step after the use of the common mulching film is saved, and the mulching film is friendly to the farmland environment and has no pollution.

At present, methods such as open-field natural exposure experiments, laboratory simulation experiments and the like are generally adopted for evaluating the performance of the degradable mulching film, the set conditions of the experiments are more ideal, and the degradation performance data of the mulching film obtained by the experiments is greatly different from the degradation performance of the mulching film in the ecological environment of a farmland. The growth cycle of rice in one season of one year is longer, the planting conditions of 'two-crops' rice are more severe, and degradation performance of the biodegradable mulching film and influence of the biodegradable mulching film on farmland soil nutrients need to be considered when the biodegradable mulching film is selected by farmers, but a field evaluation method considering degradation performance of the biodegradable mulching film and influence of the biodegradable mulching film on farmland soil nutrients does not exist in the prior art.

Disclosure of Invention

Aiming at the defects, the invention provides a field evaluation method of the biodegradable mulching film on the cultivation of the two-stage non-chemical rice, which considers the degradability of the biodegradable mulching film and the influence on the soil nutrients of the farmland.

The invention provides the following technical scheme: a field evaluation method of biodegradable mulch film on organic fertilizer rice cultivation is a two-non-chemical rice cultivation method, the two-non-chemical rice cultivation method is a rice cultivation method which does not adopt pesticides and fertilizers in the planting process of a rice field and only uses organic fertilizers, and the field evaluation method comprises the following steps:

s1: the organic matter content of soil, the weed control rate of a paddy field, the rice yield, the fragmentation degree of a biodegradable mulching film exposed on the ground surface, the functional group change and the relative molecular weight of the mulching film are used as evaluation indexes;

s2: arranging test cells with equal areas in the investigation region far away from the edge region, and adopting mechanical seedling transplanting and film mulching planting, wherein the transplanting density is 30cm multiplied by 12cm, and 7.5-8 w of basic seedlings per mu; observing and recording the mechanical damage condition of the mulching film in the laying process; observing and recording the damage degree of a mulching film exposed on the ground surface every 15 days after the rice is mechanically covered with the film, and collecting soil by adopting a quincunx point sampling method to detect the content of organic matters; collecting mulch film samples every 45 days to analyze the change of the functional groups and the relative molecular weight; meanwhile, observing the growth condition of weeds in the rice field;

s3: after the rice is harvested, the weed control rate and the rice yield of the rice field are counted, the degradation degree of the mulching film, the change of the functional group of the mulching film and the relation between the relative molecular weight change and time are analyzed, and a corresponding chart is drawn.

Further, in the step S1, the damage degree of the biodegradable mulch film is represented by a numerical grade of 0-5, and the numerical size represents different damage degrees: 0 is that the mulching film is kept complete and is not damaged; 1, a tiny crack of 0-2 cm naturally appears at the beginning of the mulching film; 2, a 2-20 cm crack appears on the mulching film; 3, the mulching film has large cracks of 20-50 cm and the number of the cracks is increased; 4, the mulching film is uniformly cracked and decomposed into a plurality of small pieces, and no large mulching film exists on the soil surface; and 5, the mulching film on the soil surface basically disappears or only slightly remains.

Further, when the organic matter content of the soil is detected in the step S2, a plum blossom point sampling method is adopted in each test cell to collect soil samples of 0-20 cm soil layers, and the organic matter content of the soil is detected.

Further, when analyzing the change of the functional groups of the mulching film in the step S2, collecting a mulching film sample in each test cell, and detecting and analyzing by adopting Fourier infrared spectroscopy, wherein the measurement range is 500-4000 cm^-1。

Further, in the step S2, the mulch film samples are collected in each test cell according to the change of the relative molecular weight of the mulch film, and are detected and analyzed by a gel chromatograph, wherein the sample injection volume is 10.00 mu L, and the time is 15.00 min.

Further, in step S2, when test cells having an equal area are arranged in the region far from the edge region in the area under consideration, the number of the test cells under consideration is not less than 5.

Further, in the step S2, the planting density of mechanical seedling planting and film mulching planting is 30cm multiplied by 12cm, and the basic seedlings per mu are 7.5-8 w.

The invention has the beneficial effects that:

1. in the method provided by the invention, the degradation mechanism of the biodegradable mulching film is fully considered by the evaluation index of the degradation performance of the biodegradable mulching film in the two types of innocent rice, and the method is comprehensive and visual and has strong intelligibility.

2. The method provided by the invention evaluates the influence of the biodegradable mulching film on soil nutrients by detecting the content of organic matters in the soil of the rice field.

Drawings

The invention will be described in more detail hereinafter on the basis of embodiments and with reference to the accompanying drawings. Wherein:

fig. 1 is an analysis diagram of the change of functional groups of the biodegradable mulch film in application example 1 of the method provided by the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The invention provides a field evaluation method of biodegradable mulching film on organic fertilizer rice cultivation, wherein two-stage non-chemical rice cultivation is a rice cultivation method which does not adopt pesticides and fertilizers in the planting process of a rice field and only uses organic fertilizers, and the field evaluation method is characterized by comprising the following steps:

s1: the organic matter content of soil, the weed control rate of a paddy field, the rice yield, the fragmentation degree of a biodegradable mulching film exposed on the ground surface, the functional group change and the relative molecular weight of the mulching film are used as evaluation indexes;

s2: arranging test cells with equal areas in the investigation region far away from the edge region, and adopting mechanical seedling transplanting and film mulching planting, wherein the transplanting density is 30cm multiplied by 12cm, and 7.5-8 w of basic seedlings per mu; observing and recording the mechanical damage condition of the mulching film in the laying process; observing and recording the damage degree of a mulching film exposed on the ground surface every 15 days after the rice is mechanically covered with the film, and collecting soil by a plum blossom point sampling method (refer to soil environmental quality standard (GB15618-1995) and soil environmental monitoring technical specification (HJ/T166-2004)) to detect the content of organic matters; collecting mulch film samples every 45 days to analyze the change of the functional groups and the relative molecular weight; meanwhile, observing the growth condition of weeds in the rice field;

s3: after the rice is harvested, the weed control rate and the rice yield of the rice field are counted, the degradation degree of the mulching film, the change of the functional group of the mulching film and the relation between the relative molecular weight change and time are analyzed, and a corresponding chart is drawn.

In the step S1, the damage degree of the biodegradable mulching film is represented by 0-5 digital grading, the degradation performance grade of the biodegradable mulching film is represented by the number size: 0 is that the mulching film is kept complete and is not damaged; 1, a tiny crack of 0-2 cm naturally appears at the beginning of the mulching film; 2, a 2-20 cm crack appears on the mulching film; 3, the mulching film has large cracks of 20-50 cm and the number of the cracks is increased; 4, the mulching film is uniformly cracked and decomposed into a plurality of small pieces, and no large mulching film exists on the soil surface; and 5, the mulching film on the soil surface basically disappears or only slightly remains.

When the organic matter content of the soil is detected in the step S2, a plum blossom point sampling method is adopted in each test cell to collect soil samples of 0-20 cm of soil, and the organic matter content of the soil is detected.

When analyzing the change of the functional groups of the mulching film in the step S2, collecting a mulching film sample in each test cell, and detecting and analyzing by adopting Fourier infrared spectroscopy, wherein the measurement range is 500-4000 cm^-1。

And step S2, collecting mulch film samples in each test cell according to the change of the relative molecular weight of the mulch film, and detecting and analyzing by using a gel chromatograph, wherein the sample injection volume is 10.00 mu L, and the time is 15.00 min.

In step S2, when test cells with equal areas are distributed in the investigation region far away from the edge region, the number of the investigated test cells is more than or equal to 5; the planting density of the mechanical seedling planting and film mulching planting is 30cm multiplied by 12cm, and the basic seedlings per mu are 7.5-8 w.

Application example 1

At 500m²10 equal areas (36 m) are distributed in the land parcel²) The test plot adopts mechanized rice transplanting and mulching film planting as contrast, the planting density is 30cm multiplied by 12cm, and the basic seedlings per mu are 7.5-8 w. The test cells are arranged randomly, and the observation period starts from the mechanized rice transplanting and film covering of the rice and runs through the whole growth period of the rice plantingAnd in the period, the mulching film is observed and monitored for 135 days. In the mechanized mulching process of the rice, the mechanical damage grade of the mulching film is 0; the appearance and the shape of the biodegradable mulching film are kept complete within 30 days after rice transplanting and mulching, and the biodegradable mulching film is not obviously damaged; after covering the mulching film for 45 days, tiny cracks and tiny holes begin to appear on the surface of the mulching film; after the rice is covered with the film for 75 days, holes and cracks are gradually enlarged and the number of the holes and the cracks is increased; after 90 days of film covering, the mulching film is evenly cracked into small pieces in the rice field, and no large mulching film exists on the ground surface basically; after covering the film for 105 days, the mulching film can not be seen on the surface of the paddy field soil basically, and the mulching film almost completely disappears. Before rice is transplanted, the organic matter content of soil is 20.48 g.kg^-1The organic matter content of the soil is in the trend of descending first and then ascending and then descending, and after the growth period of the rice is finished, the organic matter content of the mulching film soil is improved by 2.23 g.kg compared with that before the rice is planted^-1The yield is improved by 10.8 percent compared with that before planting; the organic matter content of the non-film-covered soil is increased by 0.65 g/kg^-1The yield is improved by 3.2 percent compared with the yield before planting. After the rice is harvested in 11 months in the year, the weed control rate and the rice yield are counted, the control rate of the biodegradable mulching film on weeds is 69.2 percent, the rice yield of the mulching film covered rice is 421.91 kilograms/mu, the rice yield of the mulching film uncovered rice is 386.89 kilograms/mu, the analysis and summary survey data are analyzed, and corresponding graphs of the degradation degree of the mulching film, the change of functional groups of the mulching film and the change of relative molecular weight are drawn: as shown in table 1, the analysis table is a damage degree analysis table of the part of the biodegradable mulching film exposed on the ground surface; as shown in table 2, is an analysis table of the relative molecular weight change of the biodegradable mulch film, as shown in fig. 1, is an analysis chart of the functional group change of the biodegradable mulch film.

TABLE 1

TABLE 2

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Furthermore, those skilled in the art will appreciate that while some embodiments herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the claims above, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.