CN110495275A - A kind of soil nitrous oxide emission reduction method - Google Patents

Abstract

The invention belongs to the technical field of reduction of greenhouse gas discharge, specially a kind of Soil oxidation Asia nitrogen discharge-reducing method, comprising the following steps: collect camphor tree Litter leaf, clean, air-dry；It shreds to obtain the camphor tree Litter leaf of fragment shape, deionized water is added, then extracting at constant temperature vibrates, filters, obtain camphortree leaf leaching liquor, leaching liquor is applied to soil, monitors the discharge of Soil oxidation Asia nitrogen.As a result, it has been found that after camphortree leaf leaching liquor processing soil, the sub- nitrogen discharged significant decrease of Soil oxidation.Camphor tree Litter leaf source is wide, at low cost, using flooding, simplifies integrated operation, is a kind of convenient for popularization, cost-effective nitrous oxide discharge-reducing method.

Description

A kind of soil nitrous oxide emission reduction method

technical field

The invention belongs to the technical field of greenhouse gas emission reduction, and specifically relates to a soil nitrous oxide emission reduction method.

Background technique

Soil nitrous oxide is an important greenhouse gas, which leads to the greenhouse effect, and at the same time leads to the loss of soil nitrogen, which affects the availability of soil nitrogen. Nitrous oxide can participate in various photochemical reactions and affect the stability of the ozone layer, endangering the living environment of human beings and the sustainable development of society. Among the sources of nitrous oxide, soil is the most important emission source, accounting for more than half of the total atmospheric emission. Therefore, the reduction of soil nitrous oxide emissions is of great significance for protecting the ecological environment, mitigating climate change, and improving soil nitrogen retention and availability.

At present, a variety of methods have been proposed to reduce soil nitrous oxide emissions, including the application of chemical nitrification inhibitors and biological nitrification inhibitors. However, the production cost of nitrification inhibitors is relatively high, and it is difficult to effectively and comprehensively promote them. Chinese patent CN102308687A discloses a soil treatment method for reducing nitrous oxide emissions from farmland straw bio-black charcoal, in which straw is used as raw material, pyrolyzed and ground to obtain bio-black charcoal with small particle size, and then spread on the soil surface, through plowing The rake is evenly mixed with the soil to reduce the emission of nitrous oxide from the soil. The preparation of bio-black carbon requires a lot of energy, and the production operation is complicated and not energy-saving enough. It is of great practical significance to find a soil nitrous oxide emission reduction method with the promotion potential.

Camphor tree (Cinnamomum camphora (L.) Presl), has another name called camphor, its cultivation is general, and its leaf source is wide. There are many studies on camphor tree leaves, but most of the research focus is on extracting lignans, flavonoids, d-borneol and other compounds from camphor tree leaves, or using camphor tree leaves to prepare insecticides, pesticides and compound fertilizers, etc. . The research on the greenhouse gas emission of camphor leaves has not been reported yet, and the littered leaves of camphor trees are discarded and underutilized, which leads to environmental pollution and waste of resources.

Contents of the invention

This application provides an economically feasible method for reducing soil nitrous oxide emissions. By using camphor tree litter as raw material, adding water to extract the extract solution, and then applying it to the soil surface, the monitoring found that the emission rate of nitrous oxide in the soil was significantly decline. The soil nitrous oxide emission reduction method is simple, low in cost, and easy to popularize and use.

Specifically, aiming at the deficiencies in the prior art, the present invention provides the following technical solutions:

On the one hand, the application provides a soil nitrous oxide emission reduction method, comprising the following steps:

Collect camphor leaves, wash and air-dry;

Take air-dried camphor leaves, cut them into pieces to obtain fragmented camphor leaves, add deionized water, extract at a constant temperature, then vibrate and filter to obtain camphor leaf extracts,

The camphor tree leaf extract was applied to the soil, and the emission of nitrous oxide from the soil was monitored.

Preferably, the camphor tree leaves are camphor tree litter leaves, and the air-dried camphor tree litter leaves are cut into strips with a length and width of 2-3 mm.

Preferably, the solid-to-liquid ratio of the fragmented camphor leaves and the added deionized water is 1g:19mL.

Preferably, the temperature of constant temperature leaching is 35-50°C, and the leaching time is 1-2h.

Preferably, the temperature of the constant temperature extraction is 50° C., the extraction time is 1 h, the frequency of oscillation is 80 Hz, and the oscillation is 30 min.

On the other hand, the application provides a kind of camphor tree leaf extract, and preparation process comprises:

Collect camphor tree litter, wash, air-dry, cut into pieces to obtain strips with a length and width of 2-3mm, add deionized water, extract at a constant temperature of 35-50°C for 1-2h, shake and filter to obtain camphor leaf extract liquid.

Preferably, the solid-to-liquid ratio of the camphor tree leaves of strip fragments and the deionized water added during the preparation process is 1g:19mL.

Preferably, the camphor tree leaf extract is used to reduce greenhouse gas emissions in soil.

Preferably, the camphor tree leaf extract is used to reduce the emission of nitrous oxide gas in the soil.

Compared with the prior art, the effects and benefits of the present application are:

1. Using camphor tree leaves as raw materials, especially the littered leaves of camphor tree, realizes waste reuse and avoids environmental pollution caused by burning littered leaves; the raw materials are easy to obtain and the cost is low.

2. The extract obtained by extracting camphor tree leaves with water can effectively reduce the emission of nitrous oxide in the soil and increase the nitrogen fixation capacity of the soil. Extraction with water avoids the use of organic solvents, is simple to operate, and reduces environmental pollution. At the same time, the potential impact of direct application of camphor leaves on the reduction of soil nitrogen availability and possible pests and diseases are avoided.

3. Vibration extraction after constant temperature leaching shortens the time required for leaching and improves production efficiency; at the same time, the preparation process of the camphor tree leaf extract provided by the application is simple, easy to operate, economical and practical, and is convenient for wide-scale promotion Used to reduce soil nitrous oxide emissions.

4. The research of this application shows that camphor tree leaf extract and air-dried soil are mixed according to the ratio of 1ml:3.5g, and soil gas emission is monitored. The nitrogen emission rate was significantly lower than that of the blank control group and the camphor leaf group.

After the camphor tree leaves littered into the soil, the emission rate of nitrous oxide decreased on the 3rd day after the pre-cultivation, but the process of decomposition of the camphor tree litter leaves by microorganisms would increase the carbon input of the soil, affect the nitrogen absorption, and lead to diseases and insect pests. In addition, the cumulative emission rate of soil nitrous oxide in the camphor tree leaf litter group was significantly higher than that in the camphor tree leaf extract treatment group, so the camphor tree leaf extract was an economical and effective way to reduce soil nitrous oxide emissions.

Description of drawings

Figure 1 is a graph of the measured soil nitrous oxide cumulative emission rate;

Wherein, the extract solution prepared by curve 1-Example 1, the extract solution prepared by 2-Example 2, the extract solution prepared by 3-Example 3, the extract solution prepared by 4-Example 4, 5-Example The extract prepared by example 5, the extract prepared by 6-embodiment 6, the extract prepared by 7-embodiment 7, the extract prepared by 8-embodiment 8, 9-camphor tree litter group, 10- Blank control group.

Detailed ways

The application provides a method for reducing emission of nitrous oxide in soil, the process of which includes preparing an extract of camphor leaves, applying the extract to soil, and monitoring the emission of nitrous oxide.

The preparation process of camphor tree leaf extract comprises: collect camphor tree leaf litter, wash, air-dry, cut into pieces and obtain length and width strip fragments at 2-3mm, add deionized water (solid-liquid mixture of camphor tree leaf fragments and deionized water) The ratio is 1g:19mL), leaching at 35-50°C for 1-2h at a constant temperature, oscillating at 50-90Hz for 30-60min, and filtering to obtain camphor tree leaf extract.

It is found in the test that the vibration frequency of the vibration extraction has little effect on the components of the extract, preferably 80 Hz.

In the research process of the technical scheme of the present application, all adopted camphor tree litter leaves.

Analyze the components in the camphor tree leaf extract prepared in each of the following embodiments, and the analysis method is as follows:

1. Instrument: Agilent 6560qtof

2. Test conditions:

Liquid chromatography conditions Chromatographic column: waters ACCQ-TAG ULTRA C18, 2.1×100mm, 1.7μm, part number 186003837:

Flow rate: 0.3mL/min;

Column temperature: 35°C;

Injection volume: 1μL;

DAD detection: 210nm, 254nm, 260nm, 280nm;

Mobile phase: A) aqueous solution containing 0.1% formic acid B) methanol;

Gradient program: 0-2min, 7%B; 2-20min, 93%B; 20-26, 95%B; 26-27min, 7%B, run for 5min.

Mass spectrometry conditions: Agilent 6560 HPLC-Q-TOF MS/MS

Ion source: ESI drying gas temperature: 320°C; drying gas flow rate: 10L/min;

Nebulizer pressure: 35psi Sheath gas temperature: 350℃, sheath gas flow rate: 12L/min

Fragmentation voltage: 135v

Scanning method: first-level full scan, second-level MS/MS mode, collision energy 10, 30eV. Primary and secondary scan mass range m/z 100-1700

3. Test sample preparation

Take 1mL of the extract sample, add 1mL of chromatographic grade methanol, shake for 3min, filter with a 0.22um Jinlong filter membrane, and put it into an injection bottle.

4. Database search

The compounds in the samples were identified based on Agilent MSC software and the unique TCM Chinese medicine database.

Hereinafter, the present application will be further introduced through specific embodiments. It should be noted that the following embodiments are only examples of the present application, and the technical solutions and protection scope described in the present application are not limited to the respective embodiments.

Example 1

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, the dosage is calculated by adding 19mL deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 35°C Extract in a water bath for 1 hour, then vibrate and extract at 80 Hz for 30 minutes, and filter to obtain camphor leaf extract.

Adopt aforementioned method to analyze the component in the extract solution, the results are shown in Table 1:

Table 1.

Compound name molecular formula Chinese name 8-O-Acetyl shanzhiside methyl ester C₁₉H₂₈O₁₂ Cyclosporine glucoside Acetyl catalpol C₁₈H₂₆O₁₀ Acetyl catalpol Afzelin C₂₁H₂₀O₁₀ Afotoside Aromadendrin-5,7-dimethyl ether C₁₅H₁₂O₅ Myringin-5,7-dimethyl ether Chlorogenic acid C₁₆H₁₈O₉ Chlorogenic acid Cimidahurine C₁₄H₂₀O₈ * Dehydromorronia glycone C₁₁H₁₄O₅ Anhydromorronigenin Floripavine C₁₉H₂₁NO₄ fengmenine Gerberinside C₁₆H₁₈O₈ * Hyperin C₂₁H₂₀O₁₂ * Isorhamnetin C₁₆H₁₂O₇ isorhamnetin Laurolitsine C₁₈H₁₉NO₄ * Picrodendrin A C₂₁H₂₈O₁₀ * Quercetin-3-O-alpha-L-rhamnopyranoside C₂₁H₂₀O₁₁ *

Example 2

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, the dosage is calculated by adding 19mL deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 35°C Extract in a water bath for 1 hour, then vibrate and extract at 80 Hz for 60 minutes, and filter to obtain camphor tree leaf extract.

Adopt aforementioned method to analyze the component in the extract solution, the results are shown in Table 2:

Table 2.

Example 3

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, the dosage is calculated by adding 19mL deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 35°C Extract in a water bath for 2 hours, then vibrate and extract at 80 Hz for 30 minutes, and filter to obtain camphor leaf extract.

Adopt aforementioned method to analyze the component in the extract solution, the results are shown in Table 3:

table 3.

Example 4

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, the dosage is calculated by adding 19mL deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 35°C Extract in a water bath for 2 hours, then shake and extract at 80 Hz for 60 minutes, and filter to obtain camphor leaf extract.

Adopt aforementioned method to analyze the component in the extract solution, the results are shown in Table 4:

Table 4.

Example 5

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, and the dosage is calculated by adding 19mL of deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 50°C Extract in a water bath for 1 hour, then vibrate and extract at 80 Hz for 30 minutes, and filter to obtain camphor leaf extract.

Adopt aforementioned method to analyze the component in the extract solution, the results are shown in Table 5:

table 5.

Example 6

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, and the dosage is calculated by adding 19mL of deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 50°C Extract in a water bath for 1 hour, then vibrate and extract at 80 Hz for 60 minutes, and filter to obtain camphor tree leaf extract.

Adopt aforementioned method to analyze the component in the extract solution, the results are shown in Table 6:

Table 6.

Example 7

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, and the dosage is calculated by adding 19mL deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 50°C Extract in a water bath for 2 hours, then vibrate and extract at 80 Hz for 30 minutes, and filter to obtain camphor leaf extract.

Adopt the aforementioned method to analyze the components in the extract, and the results are shown in Table 7:

Table 7.

Example 8

Collect camphor leaf litter, wash, air-dry, and cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, and the dosage is calculated by adding 19mL deionized water to 1g of camphor leaf fragments, and place at a constant temperature of 50°C Extract in a water bath for 2 hours, then shake and extract at 80 Hz for 60 minutes, and filter to obtain camphor leaf extract.

Adopt the aforementioned method to analyze the components in the extract, and the results are shown in Table 8:

Table 8.

According to the contents in Table 1-8, it can be seen that the camphor tree leaf extract prepared by the present application all contains components: cyclosporin glucoside (8-O-Acetyl shanzhiside methyl ester), acetyl catalpol (Acetylcatalpol), a Afzelin and Chlorogenic acid; 7 groups of extracts contain components Cimidahurine and Picrodendrin A, and 6 groups of extracts contain Gerberinside and Quercetin-3-O-alpha-L-rhamnopyranoside.

Example 9

Study the emission of nitrous oxide in the soil after the camphor tree leaf extract prepared in Examples 1-8 is applied to the soil.

The specific research methods are as follows:

Set blank control group (CK), camphor tree leaf litter group, camphor tree leaf extract group (①-⑧), and set up 3 parallel experiments for each group.

Weigh 35g of air-dried soil (soil sample is fresh soil under the forest, the collection time and location of each group of soil samples are the same, and each 15g of air-dried soil contains 0.29g of water) and place them in a 150mL conical flask, add 0.5 g camphor tree litter leaves, add deionized water in 3 conical flasks as a blank control group, camphor leaf extract group (24 conical flasks) add 10ml of camphor leaf extract prepared above dropwise with a pipette gun.

In order to control the water content in the air-dried soil to be 60% WHC (the field maximum water holding capacity of the soil used), the volume of deionized water added to the camphor tree leaf litter group and the blank control group was 12.36mL, and the extract group added 2.36mL deionized water in addition. ionized water.

During the cultivation process, seal the cap of the Erlenmeyer bottle with plastic wrap, and pierce 6 small holes on it, measure the total mass of the container every two days, and replenish deionized water to maintain soil moisture. After pre-incubating at 25±1°C for 2 days in the dark, start timing and collect gas on days 1, 3, 6, 10, 15, 21, 28, 35, and 42. The gas collection method is:

First, remove the plastic wrap of each Erlenmeyer flask, ventilate the flask with a blower for about 10 seconds, install the rubber stopper on the Erlenmeyer flask, inject 40ml of fresh air into the Erlenmeyer flask with a syringe, and pump 10 times continuously. Mix the gas evenly, collect 40ml of gas, close the three-way valve of the rubber stopper to seal it, and then put it into the incubator to continue culturing for 2 hours, and then collect the gas again. The N ₂ O concentration of each gas sample was measured using a gas chromatograph (Agilent7890B, Santa Clara, CA, USA) equipped with a flame ionization detector (FID) and an electron capture detector (ECD), and the emission rate and cumulative emission were calculated. rate.

The emission rate is calculated by the following equation:

In the above formula: E refers to the soil N ₂ O (ng.g ^-1 .h ^-1 ) emission rate, P is the standard atmospheric pressure (Pa), V is the headspace of the Erlenmeyer flask (cm ³ ), c is N ₂ O (ppb) concentration, △c represents the concentration difference of N ₂ O (ppb) measured after two gas collections;

△t is the gas collection interval (h), R is the universal gas constant (8.314J·mol ^-1 ·K ^-1 ), T is the absolute temperature (K), M is N ₂ O (g·mol ^-1 ) The molecular mass of the soil, m is the dry weight of the cultured soil (g).

Calculation method of cumulative emission rate

M＝Σ(F _i+1 +F _i )/2*(t _i+1 -t _i )*24

In the formula: M is the cumulative emission rate of soil N ₂ O, μg m ^-2 ; F is the flux of N ₂ O emission, μg m ² h ^-1 ; i is the sampling frequency; t _i+1 -t _i sampling Interval days.

The results of the determination are shown in Table 9 and Table 10.

Table 9. Soil nitrous oxide emission rate (ng·g ^-1 ·h ^-1 )

number of days 1 3 6 10 15 Extraction group ① 0.291447 0.669076 0.319025 0.448311 0.125132 Extraction group② 0.490201 0.218928 0.460348 0.304318 0.074257 Extraction group③ 0.011839 0.259179 0.114324 0.41025 0.173535 Extraction group④ -0.04007 0.308104 0.213729 0.37517 0.149093 Extraction group⑤ -0.30704 0.209618 0.486768 0.244655 0.220101 Extraction group⑥ -0.34482 0.473671 0.206933 0.40515 0.201607 Extraction group⑦ 0.408823 0.30583 0.258049 0.196959 0.24279 Extraction group⑧ 0.231954 0.376329 0.147567 0.339737 0.102442 Camphor deciduous group 2.331466 0.164705 0.211045 0.229552 0.135163 CK control group 2.603148 0.859084 0.690381 0.392548 0.358584 number of days twenty one 28 35 42 Extraction group ① -0.0574 0.16551 0.09689 0.119679 Extraction group② 0.145943 -0.02197 0.045139 0.080855 Extraction group③ 0.18139 0.152371 0.06198 0.12023 Extraction group④ 0.209632 0.137212 -0.03362 0.115398 Extraction group⑤ 0.15651 0.135912 -0.09021 0.302185 Extraction group⑥ 0.181983 0.148062 0.225597 0.239852 Extraction group⑦ 0.05339 0.196658 0.159718 0.141577 Extraction group⑧ 0.003744 0.03248 0.134471 0.118026 Camphor deciduous group 0.11917 0.027564 0.014439 0.050225 CK control group 0.222361 0.176106 0.151537 0.266455

The data in Table 9 shows that on the first day after 2 days of pre-cultivation, the soil nitrous oxide emission of the extract group was significantly lower than that of the camphor leaf litter group and the blank control group, indicating that the extract can rapidly reduce soil nitrous oxide emission, the effect is remarkable.

Table 10. Cumulative emission rate of nitrous oxide from soil (μg·m ^-2 )

number of days 1 3 6 10 15 Extraction group ① 0.291447352 0.960523103 1.27954839 1.727859378 1.852991435 Extraction group② 0.490200628 0.709128747 1.169476825 1.473794822 1.548051804 Extraction group③ 0.011839298 0.271018205 0.38534231 0.795592356 0.96912708 Extraction group④ -0.040067123 0.268037188 0.481766188 0.856936309 1.006029522 Extraction group⑤ -0.307044709 -0.097426969 0.389340546 0.633995827 0.854096573 Extraction group⑥ -0.344823089 0.128847731 0.335781143 0.740930967 0.942538108 Extraction group⑦ 0.408823114 0.714652811 0.972701474 1.16966049 1.412450869 Extraction group⑧ 0.231954172 0.608282793 0.755850178 1.095587172 1.198029596 Camphor deciduous group 2.331465789 2.496170488 2.70721516 2.936767565 3.07193053 CK control group 2.603148012 3.462231783 4.15261262 4.545160231 4.903744032 number of days twenty one 28 35 42 Extraction group ① 1.795589205 1.961099202 2.057989305 2.177667938 Extraction group② 1.693994465 1.672025361 1.717164451 1.798019228 Extraction group③ 1.150516995 1.302887914 1.364867628 1.485097255 Extraction group④ 1.21566139 1.352872922 1.319248185 1.434646021 Extraction group⑤ 1.010607008 1.146518759 1.056311219 1.358495882 Extraction group⑥ 1.1245214 1.272583266 1.49817982 1.738031567 Extraction group⑦ 1.465840735 1.662498823 1.822216324 1.963793419 Extraction group⑧ 1.201773526 1.234253892 1.368724583 1.486750235 Camphor deciduous group 3.191100554 3.218664361 3.233103219 3.283328404 CK control group 5.126105265 5.302211292 5.453748657 5.720203504

The cumulative emission rate of nitrous oxide in the deciduous camphor tree leaves group and the blank control group was always greater than that in the camphor tree leaf extract group, indicating that the extract solution had a significant effect on reducing soil nitrous oxide emissions.

The preparation method of camphor tree leaf extract is simple, the source of raw materials is wide, and it is easy to popularize. It is a very economical method for reducing soil nitrous oxide emissions and is of great significance.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention.

Claims (10)

1. A soil nitrous oxide emission reduction method, is characterized in that, comprises the following steps: Collect camphor leaves, wash and air-dry; Take air-dried camphor leaves, cut them into pieces to obtain fragmented camphor leaves, add deionized water, extract at a constant temperature, then vibrate and filter to obtain camphor leaf extracts, The camphor tree leaf extract was applied to the soil, and the emission of nitrous oxide from the soil was monitored. 2. soil nitrous oxide emission reduction method as claimed in claim 1, is characterized in that, described camphor tree leaf is camphor tree leaf litter, and the camphor tree leaf litter after air-dry is cut into length and width in the strip of 2-3mm debris. 3. soil nitrous oxide emission reduction method as claimed in claim 1 or 2, is characterized in that, the solid-to-liquid ratio of the camphor leaves of fragments and the deionized water added is 1g:19mL. 4. The method for reducing emission of nitrous oxide in soil according to claim 3, characterized in that the temperature of the constant temperature extraction is 35-50°C, and the extraction time is 1-2h. 5. The soil nitrous oxide emission reduction method according to claim 4, characterized in that the oscillation time is 30-60min, and the oscillation frequency is 50-90Hz. 6. The method for reducing soil nitrous oxide emission according to claim 5, characterized in that, the temperature of constant temperature extraction is 50° C., the extraction time is 1 h, the frequency of oscillation is 80 Hz, and the oscillation is 30 min. 7. a camphor tree leaf extract, is characterized in that, preparation process comprises: Collect camphor tree litter, wash, air-dry, cut into pieces to obtain strip fragments with a length and width of 2-3mm, add deionized water, extract at a constant temperature of 35-50°C for 1-2h, vibrate and filter to obtain the camphor tree leaf extract. 8. a kind of camphor tree leaf extract as claimed in claim 7, is characterized in that, the solid-liquid ratio of the camphor tree leaf of strip fragment and the deionized water added is 1g:19mL in the preparation process. 9. a kind of camphor tree leaf extract as claimed in claim 7 or 8, is characterized in that, described camphor tree leaf extract is used for reducing the emission of greenhouse gases in soil. 10. a kind of camphor leaf extract as claimed in claim 9, is characterized in that, described camphor leaf extract is used for reducing the emission of nitrous oxide gas in soil.