Method for evaluating activity function of livestock and poultry manure compost and application of method

Abstract

The invention relates to a livestock manure compost activity function evaluation method and application thereof, and belongs to the technical field of organic waste treatment. The method for evaluating the activity function of the livestock and poultry manure compost comprises the following steps: measuring the humic acid content and the relative content of humic acid functional groups of the livestock and poultry manure compost, and calculating an alkylation index and an E4 / E6 value; evaluating and / or representing the functional activity of the livestock and poultry manure compost according to the humic acid content, the carboxyl carbonyl carbon relative content, the alkylation index and the E4 / E6 value. The evaluation method disclosed by the invention comprises a plurality of evaluation indexes related to active functions of promoting crop growth, promoting nutrient absorption, reducing soil ammonia volatilization and the like, and has the advantages of strong comprehensiveness, strong systematicness, high accuracy and relatively perfect performance.

Description

Technical Field

[0001] The invention relates to the technical field of organic waste treatment, and in particular to an evaluation method for the active function of livestock and poultry manure composting and an application thereof. Background Art

[0002] With the development of livestock and poultry farming, the amount of livestock and poultry manure produced has increased, with an average annual production of 420 million tons. Livestock and poultry manure contains rich nutrient resources such as organic matter, nitrogen, phosphorus, and potassium. It is estimated that the production of nitrogen, phosphorus, and potassium in livestock and poultry manure in 2019 was 928,000 tons, 604,000 tons, and 686,000 tons, respectively. However, due to the untimely and unscientific treatment of livestock and poultry manure, a huge amount of livestock and poultry manure has been accumulated and wasted, causing pollution to the environment, including eutrophication of water bodies and soil acidification.

[0003] Aerobic composting is an important way to utilize livestock and poultry manure as fertilizer. The compost obtained after aerobic composting of livestock and poultry manure has the characteristics of long-lasting fertilizer effect and comprehensive nutrients. Long-term application can effectively increase the content of soil organic matter, improve soil physical and chemical properties, promote crop growth and nutrient absorption, and can also reduce soil ammonia volatilization and reduce nitrogen loss in farmland through adsorption and complexation. At present, there are many evaluation indicators for the maturity of livestock and poultry manure compost, such as humic acid structure, spectral characteristics of soluble organic carbon, etc., but there are few indicators for predicting and evaluating the functional activity of compost, and the prior art has not yet disclosed an evaluation method that can comprehensively and systematically characterize the functional activity of livestock and poultry manure compost. Summary of the invention

[0004] The purpose of the present invention is to provide a method for evaluating the activity function of livestock and poultry manure compost and its application in view of the defects in the above-mentioned prior art, so as to solve the problem that the prior art cannot comprehensively and systematically evaluate and / or characterize the functional activity of livestock and poultry manure compost.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for evaluating the activity function of livestock and poultry manure composting, comprising the following steps:

[0007] (1) Determination of humic acid content in livestock and poultry manure compost;

[0008] (2) Determination of the relative content of humic acid functional groups in livestock and poultry manure compost;

[0009] The relative content of humic acid functional groups includes the relative content of alkyl carbon, the relative content of alkoxy carbon, and the relative content of carboxyl carbonyl carbon;

[0010] (3) calculating the alkylation index according to the relative content of alkyl carbon and the relative content of alkoxy carbon in step (2);

[0011] (4) Determine the absorbance of soluble organic carbon in livestock and poultry manure compost at 465nm and 665nm, and calculate the E4 / E6 value;

[0012] (5) Evaluate and / or characterize the functional activity of livestock and poultry manure compost based on the humic acid content, relative content of carboxyl carbonyl carbon, alkylation index and E4 / E6 value of livestock and poultry manure compost.

[0013] Preferably, the method for determining the humic acid content in step (1) is sodium hydroxide extraction-loss on ignition method.

[0014] Preferably, the relative content of humic acid functional groups in step (2) is determined by: 13 C cross-polarization / magic angle spinning-NMR method.

[0015] Preferably, the calculation formula of the alkylation index in step (3) is: alkylation index = relative content of alkyl carbon / relative content of alkoxy carbon.

[0016] Preferably, the absorbance value in step (4) is determined by ultraviolet-visible spectrophotometry.

[0017] Preferably, when the humic acid content of livestock and poultry manure compost is ≥100 g / kg, 1.5<E4 / E6 value<2.0, and alkylation index>1.4, the livestock and poultry manure compost has the function of promoting crop growth and nutrient absorption;

[0018] When the humic acid content of the livestock and poultry manure compost is ≥100 g / kg and the relative content of carboxyl carbonyl carbon is >19%, the livestock and poultry manure compost has the function of reducing soil ammonia volatilization.

[0019] Preferably, the livestock and poultry manure compost is obtained by aerobic fermentation;

[0020] The aerobic fermentation method is windrow aerobic fermentation, tank aerobic fermentation or reactor composting aerobic fermentation.

[0021] The present invention also provides application of the evaluation method in evaluating and / or characterizing the functional activity of livestock and poultry manure compost.

[0022] The present invention has the following technical effects and advantages:

[0023] The present invention studies the change characteristics of humic acid and soluble organic carbon in livestock and poultry manure compost through multiple batches of composting experiments, specifically compares the change characteristics of humic acid functional group structure and soluble organic carbon spectral parameters in different batches of livestock and poultry manure compost, analyzes the correlation between the quality index of livestock and poultry manure compost and the active functions such as promoting crop growth, promoting nutrient absorption, and reducing soil ammonia volatilization, and provides a scientific basis for screening, evaluating and / or characterizing the functional activity index of livestock and poultry manure compost;

[0024] The present invention establishes a comprehensive and reasonable evaluation method for the active function of livestock and poultry manure composting, covering multiple evaluation indicators such as humic acid content, relative content of carboxyl carbonyl carbon, alkylation index, E4 / E6 value, etc., effectively avoiding the deviation that may exist and be caused by using a single evaluation indicator, and has the advantages of strong comprehensiveness, strong systematicity, high accuracy, and relative perfection, and can provide theoretical support for the high-value utilization of livestock and poultry manure composting. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The seed germination index of each batch of livestock manure compost;

[0026] Figure 2 is the humic acid content of each batch of livestock manure compost;

[0027] Figure 3 is the soil NH3 volatilization rate of each compost. DETAILED DESCRIPTION

[0028] The present invention provides a method for evaluating the activity function of livestock and poultry manure composting, comprising the following steps:

[0029] (1) Determination of humic acid content in livestock and poultry manure compost;

[0030] (2) Determination of the relative content of humic acid functional groups in livestock and poultry manure compost;

[0031] The relative content of humic acid functional groups includes the relative content of alkyl carbon, the relative content of alkoxy carbon, and the relative content of carboxyl carbonyl carbon;

[0032] (3) calculating the alkylation index according to the relative content of alkyl carbon and the relative content of alkoxy carbon in step (2);

[0033] (4) Determine the absorbance of soluble organic carbon in livestock and poultry manure compost at 465nm and 665nm, and calculate the E4 / E6 value;

[0034] (5) Evaluate and / or characterize the functional activity of livestock and poultry manure compost based on the humic acid content, relative content of carboxyl carbonyl carbon, alkylation index and E4 / E6 value of livestock and poultry manure compost.

[0035] In the present invention, the method for determining the humic acid content in step (1) is sodium hydroxide extraction-loss on ignition method.

[0036] In the present invention, the relative content of humic acid functional groups in step (2) is determined by: 13 C cross-polarization / magic angle spinning-NMR method.

[0037] In the present invention, the calculation formula of the alkylation index in step (3) is: alkylation index = relative content of alkyl carbon / relative content of alkoxy carbon.

[0038] In the present invention, the absorbance value in step (4) is determined by ultraviolet-visible spectrophotometry.

[0039] In the present invention, when the humic acid content of livestock and poultry manure compost is ≥100 g / kg, 1.5<E4 / E6 value<2.0, and alkylation index>1.4, the livestock and poultry manure compost has the function of promoting crop growth and nutrient absorption;

[0040] When the humic acid content of the livestock and poultry manure compost is ≥100 g / kg and the relative content of carboxyl carbonyl carbon is >19%, the livestock and poultry manure compost has the function of reducing soil ammonia volatilization.

[0041] In the present invention, the livestock and poultry manure compost comprises livestock and poultry manure and auxiliary materials;

[0042] The mass ratio of the livestock and poultry manure to the auxiliary materials is 8-20:2-6, preferably 12.2:5.

[0043] In the present invention, the livestock and poultry manure includes one or more of chicken manure, pig manure and cow manure;

[0044] The auxiliary materials include one or more of rice straw, wheat straw, vegetable straw, rice husk, rice husk, mushroom residue, sawdust and kitchen waste.

[0045] In the present invention, the livestock and poultry manure compost is obtained by aerobic fermentation;

[0046] The aerobic fermentation method is windrow aerobic fermentation, tank aerobic fermentation or reactor composting aerobic fermentation;

[0047] The aerobic fermentation time is 49 to 70 days, preferably 56 days.

[0048] In the present invention, the aerobic fermentation method is intermittent forced ventilation combined with timed turning;

[0049] The ventilation rate of the intermittent forced ventilation is 0.3-0.8 L / (kg·min), preferably 0.5 L / (kg·min); the ventilation interval of the intermittent forced ventilation is 10-30 min interval every 20-40 min of ventilation, preferably 20 min interval every 20-40 min of ventilation, and more preferably 20 min interval every 30 min of ventilation;

[0050] The time interval for the timed turning and tossing is 5 to 10 days, preferably 7 days.

[0051] The present invention also provides application of the evaluation method in evaluating and / or characterizing the functional activity of livestock and poultry manure compost.

[0052] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0053] The pilot fermentation workshop of the present invention is located in Jiangsu Academy of Agricultural Sciences;

[0054] Among the test materials of the present invention, the tested Chinese cabbage variety is Nanjing Aijiaohuang, purchased from Nanjing Wanbang Seed Co., Ltd.; the tested watermelon variety is Qilin, purchased from Shangrao Ganfeng Seed Co., Ltd.; the tested soil is paddy soil, the texture is loam, collected from Jiangsu Academy of Agricultural Sciences;

[0055] In the apparatus and equipment of the present invention, the closed reactor was purchased from Jiangsu Zhongke New Ecological Technology Co., Ltd., Kjeltec TM The 8400 automatic nitrogen analyzer was purchased from Foss, Sweden.

[0056] Example 1: Preparation of livestock and poultry manure compost

[0057] Livestock and poultry manure such as pig manure, chicken manure, and cow manure and auxiliary materials such as rice straw, wheat straw, vegetable straw, rice husk, rice husk, and kitchen waste were used as raw materials for livestock and poultry manure composting. The raw material combination for livestock and poultry manure composting was set according to the compatibility and dosage shown in Table 1. A total of 12 batches were set, namely A1~A12. A closed reactor was used for aerobic fermentation in a pilot fermentation workshop. The fermentation process adopted intermittent forced ventilation combined with timed turning. The ventilation rate was 0.5L / (kg·min), the ventilation interval was 30min for each ventilation and 20min for each intermittent ventilation, and the turning was done once a week. The fermentation was 56d in total, and 12 batches of livestock and poultry manure compost were obtained.

[0058] Table 1 Raw materials for each batch of livestock and poultry manure composting

[0059] batch Livestock and poultry manure (wet weight) Excipients (wet weight) A1 Pig manure 15.5kg Rice straw 3.3kg A2 Pig manure 14.0kg Wheat straw 3.5kg A3 Pig manure 13kg Rice straw 5.5kg A4 Chicken manure 18.5kg Rice straw 5.9kg A5 Chicken manure 17kg Rice husk 4.5kg A6 Chicken manure 20kg Rice husk 2kg A7 Pig manure 13kg Rice husk 1.5kg + rice straw 3.5kg A8 Pig manure 5kg + cow manure 9kg Rice straw 5kg A9 Chicken manure 6kg + pig manure 6.7kg Rice husk 4kg A10 Chicken manure 8kg 2kg kitchen waste + 4kg rice straw A11 Pig manure 10kg Rice straw 3kg + vegetable straw 3kg A12 Chicken manure 5.5kg + cow manure 6.7kg Rice husk 3kg + rice straw 2kg

[0060] Example 2: Determination of indicators for composting livestock and poultry manure

[0061] Seed germination index (GI) is an indicator for evaluating the maturity of livestock and poultry manure compost. The GI of each batch of livestock and poultry manure compost prepared in Example 1 was determined according to the method disclosed in "Organic Fertilizer NY / T 525-2021", and the maturity of each batch of livestock and poultry manure compost was evaluated in combination with the evaluation standard. The evaluation standard is: GI>50% indicates that the livestock and poultry manure compost is basically mature; GI>70% indicates that the livestock and poultry manure compost is completely mature. The results are as follows: Figure 1 shown.

[0062] Humic acid is an active functional product in the process of livestock and poultry manure composting fermentation. The humic acid content is an indicator for evaluating the quality of livestock and poultry manure compost. The humic acid content of each batch of livestock and poultry manure compost prepared in Example 1 was determined by sodium hydroxide extraction-loss on ignition method disclosed in the literature by Tu Qiaoping (Tu Qiaoping. Study on the influence and mechanism of biochar addition on humification of pig manure compost [D]. Zhejiang University, 2014). The results are as follows: Figure 2 shown.

[0063] Alkyl carbon, alkoxy carbon, aromatic carbon, and carboxyl carbonyl carbon are the main humic acid functional groups of organic matter in livestock and poultry manure composting. The relative content of humic acid functional groups is an indicator for evaluating the composting activity of livestock and poultry manure. 13 C-NMR) analyses during composting of olive mill wastes plus straw [J]. Bioresource Technology, 2004, 93 (3): 285-290) 13 C cross-polarization / magic angle spinning-NMR method ( 13 The humic acid functional group content of each batch of livestock manure compost prepared in Example 1 was determined by CCP / MAS-NMR, wherein the NMR spectrum of alkyl carbon was located at 0-45 ppm, the NMR spectrum of alkoxy carbon was located at 45-110 ppm, the NMR spectrum of aromatic carbon was located at 110-160 ppm, and the NMR spectrum of carboxyl carbonyl carbon was located at 160-200 ppm; then the peak area of ​​each humic acid functional group was fitted using MestReNova software to obtain the relative content of each humic acid functional group (including the relative content of alkyl carbon, the relative content of alkoxy carbon, the relative content of aromatic carbon, and the relative content of carboxyl carbonyl carbon), and the hydrophobicity index (HB / HI), alkylation index (A / OA), and aromatization index (ARM) were calculated, and the results are shown in Table 2.

[0064] The calculation formula of HB / HI is:

[0065] The calculation formula of A / OA is:

[0066] The calculation formula of ARM is:

[0067]

[0068] The E2 / E3 value is used to track the relative molecular size and aromaticity of organic matter in livestock and poultry manure compost, and is negatively correlated with the molecular weight of organic matter, the number of aromatic structures, and the degree of humification; the E4 / E6 value is the humification coefficient, which is used to indicate the condensation degree of humic acid and the aromatization degree of aromatic components in the organic matter in livestock and poultry manure compost, and is negatively correlated with the condensation degree and aromatization degree of organic matter. The batches of livestock and poultry manure compost prepared in Example 1 were mixed with 0.05 mol / L sodium bicarbonate solution at a solid-liquid ratio of 1:10, and filtered through a 0.45 μm filter membrane to obtain a compost extract; the absorbance values ​​of soluble organic carbon of each compost extract at 254 nm, 365 nm, 465 nm, and 665 nm were determined by ultraviolet-visible spectrophotometry, and the E2 value, E3 value, E4 value, and E6 value were obtained accordingly, and the E2 / E3 value and E4 / E6 value were calculated, and the results are shown in Table 2.

[0069] Table 2 Quality indicators of each batch of livestock and poultry manure compost

[0070]

[0071]

[0072] The results show that the GI of each batch of livestock and poultry manure compost is independently higher than 70%, indicating that the 12 batches of livestock and poultry manure compost prepared in Example 1 have reached complete maturity and meet the implementation standard of organic fertilizer; the humic acid content of each batch of livestock and poultry manure compost is 110-160 g / kg, that is, the humic acid content of the 12 batches of livestock and poultry manure compost is independently greater than 100 g / kg; the relative content of alkyl carbon in each batch of livestock and poultry manure compost is 13%-46%, the relative content of alkoxy carbon is 18%-47%, the relative content of aromatic carbon is 22%-43%, the relative content of carboxyl carbonyl carbon is 3%-20%, the E2 / E3 value is 1.44-2.67, and the E4 / E6 value is 1.17-4.95.

[0073] Example 3: Evaluation of the function of livestock manure compost in promoting crop growth and nutrient absorption

[0074] The poultry and livestock manure compost prepared in Example 1 was added to peat at a ratio of 1%, mixed thoroughly and then transferred to plug trays, and Nanjing dwarf yellow cabbage seeds were sown in each plug tray. Water was irrigated once every 2 days after the seedlings emerged, and the plug tray containing only peat was used as a control. 45 days after the cabbage seeds were sown, the aboveground fresh weight and root fresh weight of the cabbage seedlings were measured; another cabbage seedling was digested with sulfuric acid-hydrogen peroxide using Kjeltec TM The total nitrogen content (TN) of the Chinese cabbage seedlings was determined by an 8400 automatic nitrogen analyzer. The total phosphorus content (TP) and total potassium content (TK) of the Chinese cabbage seedlings were determined by referring to the molybdenum antimony colorimetric method and flame photometer method published by Bao Shidan et al. in "Soil Agrochemical Analysis". The results are shown in Table 3. At the same time, the correlation between the physiological indicators of the Chinese cabbage seedlings and the quality indicators of each batch of poultry and livestock manure compost was analyzed. The results are shown in Table 4.

[0075] Table 3 Physiological parameters of Chinese cabbage cultivated under composting of livestock manure in each batch

[0076]

[0077] Table 4 Correlation between physiological parameters of pakchoi seedlings and quality parameters of each batch of livestock manure compost

[0078]

[0079] In the table, * indicates significant correlation at the P < 0.05 level, and ** indicates extremely significant correlation at the P < 0.01 level.

[0080] The results showed that under the treatment of various batches of livestock manure composting, the aboveground fresh weight and root fresh weight of Chinese cabbage seedlings were higher than the control to varying degrees; compared with the control, the aboveground fresh weight increased by 0.6% to 101%, the root fresh weight increased by 25.8% to 100%, and TN, TP and TK increased by an average of 29.7%, 31.0% and 19.2%, respectively; This indicates that the livestock manure composting of the present invention has a more obvious effect on promoting the growth and development of crop roots, and can also promote the accumulation of nitrogen and phosphorus nutrients in the aboveground part of crops.

[0081] The results of correlation analysis showed that the aboveground fresh weight and root fresh weight of pakchoi seedlings were negatively correlated with the E2 / E3 value, E4 / E6 value, relative content of alkoxy carbon, relative content of aromatic carbon, and ARM of each batch of poultry and livestock manure compost, among which they were significantly negatively correlated with the E4 / E6 value; the aboveground fresh weight and root fresh weight of pakchoi seedlings were positively correlated with the relative content of alkyl carbon, relative content of carboxyl carbonyl carbon, HB / HI, and A / OA of each batch of poultry and livestock manure compost, among which they were significantly positively correlated with A / OA. Among them, the E4 / E6 values ​​of livestock manure composts in batches A9, A10 and A12 were independently greater than 1.5 and less than 2.0, and the A / OA were independently greater than 1.4. The aboveground fresh weight and root fresh weight of pakchoi seedlings cultured with livestock manure composts in batches A9, A10 and A12 were both large, indicating that when the humic acid content of livestock manure compost is ≥100 g / kg, 1.5<E4 / E6 value<2.0, and alkylation index>1.4, the livestock manure compost has the function of promoting crop growth and nutrient absorption.

[0082] Example 4: Evaluation of the function of livestock manure composting in reducing soil ammonia volatilization

[0083] 1.0000 g of each batch of livestock manure compost prepared in Example 1 was evenly spread on the micro electronic balance pan, and then 40 mL of 25% NH3·H2O solution was placed in the micro electronic balance and outside the weighing pan, and the micro electronic balance was sealed for 60 min. After the micro electronic balance reading was stable, the mass of each batch of livestock manure compost was recorded, and each batch of livestock manure compost without NH3·H2O solution was used as the corresponding control, and the NH3 adsorption capacity was calculated. The results are shown in Table 5; At the same time, the NH3 adsorption capacity (q e ) and the correlation between them and the quality indexes. The results are shown in Table 6.

[0084] q e The calculation formula is:

[0085] Where: m1 is the initial mass of each batch of livestock manure compost (1.0000 g), and m0 is the mass of each batch of livestock manure compost after sealing for 60 minutes (g).

[0086] Table 5 NH3 adsorption capacity of each batch of livestock manure compost

[0087] batch <![CDATA[q e (mg / g)]]> batch <![CDATA[q e (mg / g)]]> A1 18.14 A7 50.76 A2 25.33 A8 44.02 A3 30.07 A9 38.22 A4 36.83 A10 57.49 A5 49.1 A11 70.72 A6 42.22 A12 60.49

[0088] Table 6 Correlation between NH3 adsorption capacity and quality indexes of each batch of livestock manure compost

[0089]

[0090] In the table, * indicates significant correlation at the P < 0.05 level, and ** indicates extremely significant correlation at the P < 0.01 level.

[0091] The results showed that the adsorption capacity of NH3 by different batches of livestock manure compost varied greatly.

[0092] The results of correlation analysis showed that the q of each batch of livestock manure composting e It is extremely significantly positively correlated with the relative content of carboxyl carbonyl carbon and significantly negatively correlated with the relative content of alkoxy carbon. Among them, the relative content of carboxyl carbonyl carbon in the A11 and A12 batches of livestock manure compost is independently greater than 19%, and its NH3 adsorption capacity is independently higher than 60 mg / g, indicating that when the humic acid content of livestock manure compost is ≥100 g / kg and the relative content of carboxyl carbonyl carbon is greater than 19%, the livestock manure compost has the function of reducing soil ammonia volatilization.

[0093] Experimental Example 1: Verification of the function of compost in promoting crop growth and nutrient absorption

[0094] The raw materials were respectively combined into 100 kg chicken manure + 20 kg straw and 100 kg pig manure + 20 kg rice husk and put into a closed reactor, and aerobic fermentation was carried out by the method described in Example 1. After fermentation for 56 days, compost I and compost II were obtained respectively; each compost was air-dried, crushed and passed through a 2 mm sieve, and the humic acid content, relative content of humic acid functional groups, E4 value and E6 value of each compost were determined by referring to the method described in Example 2, and the E4 / E6 value and A / OA value were calculated. The results are shown in Table 7.

[0095] Compost I and compost II were added to peat at a ratio of 2%, and a Qilin variety watermelon seedling test was carried out, and compound fertilizers with equal nitrogen, phosphorus and potassium contents were added as a control; the watermelon seedlings were harvested when they were two-leaf and one-heart stage, and the plant height and stem diameter of the watermelon seedlings were measured, and the aboveground fresh weight, TN, TP and TK of the watermelon seedlings were measured referring to the method described in Example 3, and then the promoting effect of each compost on the growth and nutrient absorption of the watermelon seedlings was evaluated. The results are shown in Table 8.

[0096] Table 7 Quality indexes of various composts

[0097]

[0098] Table 8 Physiological parameters of watermelon seedlings cultured under different composts

[0099]

[0100] The results showed that the humic acid content of compost I and compost II was independently greater than 100 g / kg, the E4 / E6 values ​​were independently between 1.5 and 2.0, and the A / OA values ​​were independently greater than 1.4, indicating that compost I and compost II in this experimental example both have the function of promoting crop growth and nutrient absorption.

[0101] The watermelon seedling experiment showed that compared with the control, the watermelon seedlings cultivated with compost I and compost II had larger plant height, stem thickness and aboveground fresh weight, and higher TN, TP and TK of the watermelon seedlings, indicating that compost I and compost II in this experimental example do have the function of promoting crop growth and nutrient absorption.

[0102] Experimental Example 2: Verification of the Function of Compost in Reducing Soil Ammonia Volatilization

[0103] Paddy soil was collected near Jiangsu Academy of Agricultural Sciences, and gravel, plant roots, etc. were cleaned. After air-drying and passing through a 2 mm sieve, 100 g of the soil was taken and placed in culture bottles respectively. Each compost prepared in Experimental Example 1 was added to the paddy soil at a ratio of 2% and mixed thoroughly to obtain mixed loam. Urea with the same nitrogen content was added to the paddy soil as a control, and the soil moisture content of the mixed loam was controlled to be 60% of the field water holding capacity. The soil was cultured at 25°C for 14 days, and gas samples were collected on the 1st, 2nd, 3rd, 5th, and 7th days of culture. The soil NH3 volatilization rate of each compost was determined by static absorption-boric acid titration. The results are shown in FIG. Figure 3 shown.

[0104] The results showed that the humic acid content of compost Ⅰ and compost Ⅱ was independently greater than 100g / kg, and the relative content of carboxyl carbonyl carbon was independently greater than 19%, indicating that compost Ⅰ and compost Ⅱ in this experimental example both have the function of reducing soil ammonia volatilization;

[0105] Compared with the control, the soil NH3 volatilization rate of the mixed loam obtained by adding compost I and compost II was significantly reduced, and the maximum volatilization rate was only 22.4% and 30.5% of the control, respectively, and the average volatilization rate was only 26.1% and 27.7% of the control, respectively. This shows that compost I and compost II in this experimental example do have the function of reducing soil ammonia volatilization.

[0106] As can be seen from the above embodiments, the present invention provides an evaluation method for the active function of livestock and poultry manure compost and its application. The evaluation method of the present invention includes evaluation indicators such as humic acid content, relative content of carboxyl carbonyl carbon, alkylation index, E4 / E6 value, etc., which are relevant to the active functions such as promoting crop growth, promoting nutrient absorption, and reducing soil ammonia volatilization, effectively avoiding the deviation that may exist and be caused by using a single evaluation indicator, and has the characteristics of strong comprehensiveness, strong systematicity, high accuracy, and relative perfection.

[0107] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for evaluating the activity function of livestock and poultry manure composting, characterized in that: The steps include: (1) Determination of humic acid content in livestock and poultry manure compost; (2) Determination of the relative content of humic acid functional groups in livestock and poultry manure compost; The relative content of humic acid functional groups includes the relative content of alkyl carbon, the relative content of alkoxy carbon, and the relative content of carboxyl carbonyl carbon; (3) calculating the alkylation index according to the relative content of alkyl carbon and the relative content of alkoxy carbon in step (2); (4) Determine the absorbance of soluble organic carbon in livestock and poultry manure compost at 465nm and 665nm, and calculate the E4 / E6 value; (5) Evaluate and / or characterize the functional activity of livestock and poultry manure compost based on the humic acid content, relative content of carboxyl carbonyl carbon, alkylation index and E4 / E6 value of livestock and poultry manure compost.

2. The evaluation method according to claim 1, characterized in that: The method for determining the humic acid content in step (1) is sodium hydroxide extraction-loss on ignition method.

3. The evaluation method according to claim 2, characterized in that: The relative content of humic acid functional groups in step (2) is determined by: 13 C cross-polarization / magic angle spinning-NMR method.

4. The evaluation method according to claim 3, characterized in that: The calculation formula of the alkylation index in step (3) is: alkylation index = relative content of alkyl carbon / relative content of alkoxy carbon.

5. The evaluation method according to claim 4, characterized in that: The absorbance value of step (4) is determined by ultraviolet-visible spectrophotometry.

6. The evaluation method according to any one of claims 1 to 5, characterized in that: When the humic acid content of livestock and poultry manure compost is ≥100 g / kg, 1.5<E4 / E6 value<2.0, and alkylation index>1.4, the livestock and poultry manure compost has the function of promoting crop growth and nutrient absorption; When the humic acid content of the livestock and poultry manure compost is ≥100 g / kg and the relative content of carboxyl carbonyl carbon is >19%, the livestock and poultry manure compost has the function of reducing soil ammonia volatilization.

7. The evaluation method according to claim 6, characterized in that: The livestock and poultry manure compost is obtained by aerobic fermentation; The aerobic fermentation method is windrow aerobic fermentation, tank aerobic fermentation or reactor composting aerobic fermentation.

8. Use of the evaluation method according to any one of claims 1 to 7 in evaluating and / or characterizing the functional activity of livestock and poultry manure compost.

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