The application of biomarkers to study the molecular composition of soil organic matter (SOM) can be used to analyze the source and degradation of SOM and reveal the stability mechanism of soil organic carbon (SOC) at the molecular level. In order to further clarify the effects of different land use patterns (farmland, grassland, and forest) on the molecular composition of SOM, the changes in molecular composition of organic matter (free lipids, cutin, suberin, and lignin) on a global scale were studied using a meta-analysis method. The results showed that there were significant differences in the molecular composition of organic matter under different land use patterns. The contents of free lipids (n-alkanes, n-alkanols, n-alkanoic acids, and cyclic lipids), cutin, and lignin phenols in forest soil were significantly higher than those in grassland and farmland. There was no significant difference in the content of suberin between grassland and forest soil. The ratio of suberin to cutin in grassland was the highest, with an average of 2.96, and the averages of farmland and forest were 1.68 and 2.21, respectively. The ratio of syringic acid to syringaldehyde (Ad/Al)S and the ratio of vanillic acid to vanillin (Ad/Al)V of farmland soil were the largest, which were 1.25 and 1.58, respectively, and were significantly higher than those in grassland (0.46 and 0.69) and forest (0.78 and 0.7). The results of correlation analysis showed that in farmland soil, suberin was significantly correlated with mean annual precipitation (MAP) and clay; cutin was significantly correlated with clay; and lignin was significantly correlated with mean annual temperature (MAT), MAP, sand, and bulk density. In grassland soil, total free lipids were significantly correlated with MAP and bulk density; suberin and cutin were significantly correlated with MAT and MAP; and lignin was significantly correlated with MAP, pH, sand, and bulk density. However, only lignin was significantly correlated with MAP and sand in forest soils. Overall, the contents of SOC and molecular components in forest soil were higher under the three land use practices, and the contribution of plant roots to SOM in grassland soil was greater. In farmland soil, the degradation of lignin was accelerated due to human farming activities. Future research should focus on the regulation of soil physicochemical properties and climatic conditions on the molecular composition of SOM.
Objective: To investigate the clinical application of preoperative adductor canal block combined with general anaesthesia in elderly patients with total knee arthroplasty. Methods: Seventy-four patients scheduled for elective TKA in Shaanxi Nuclear Industry Hospital No. 215 were selected and were assigned into group A (continuous ACB prior to the induction of anaesthesia) and group B (continuous ACB after extraction of the tracheal catheter post-operatively) according to the random number table method. Pre and postoperative plasma adrenaline and noradrenaline levels were measured; mean arterial pressure (MAP) and heart rate (HR) were recorded at the admission and the surgical skin incision; intraoperative sufentanil dosage, number of analgesic pump presses at 48 h postoperatively; postoperative adverse effects and length of stay were recorded; resting and active VAS pain scores were assessed at 4, 8, 12, 24, and 48 h postoperatively. Results: Group B experienced a substantial increase in MAP and HR at the time of surgical skin incision, while group A registered a smaller change and a stable haemodynamic profile (P < 0.05). The plasma adrenaline and norepinephrine concentrations in group B were elevated compared to the preoperative period, differentially with group A. Group A received less intraoperative sufentanil than Group B (P < 0.05). Conclusion: Collectively, postoperative resting VAS scores and active VAS scores remained lower in TKA patients who were subjected to preoperative and postoperative ACB, while preoperative ACB in conjunction with general anaesthesia decreased intraoperative sufentanil dosage, contained the surgical stress response, and maintained a stable intraoperative haemodynamic state, in what is probably a preferable option for elderly patients undergoing TKA. This study has served as a reference for postoperative patients to reduce their medication and for clinicians in the treatment going forward.
Arthroplasty, Replacement, Knee , Nerve Block , Humans , Aged , Arthroplasty, Replacement, Knee/adverse effects , Arthroplasty, Replacement, Knee/methods , Nerve Block/methods , Pain, Postoperative/etiology , Sufentanil/therapeutic use , Anesthesia, General , Epinephrine/therapeutic use , Norepinephrine/therapeutic use
This study intended to examine the influence of biochar application on soil carbon content under different tillage conditions. For this, an indoor incubation experiment was performed with treatments included wheat straw-derived biochar application (0, 5, and 20 g·kg-1) and soil with different tillage measures (ploughing and no-tillage). The effects of biochar addition on soil organic carbon (SOC), dissolved organic carbon (DOC), soil microbial biomass carbon (MBC), readily oxidized organic carbon (ROC), soil inorganic carbon (SIC), pH, water soluble calcium and magnesium, and soil CO2 emissions were analyzed. The results showed that:â Compared with the control, the contents of SOC, ROC, DOC, and water soluble Ca and Mg increased by 20.3%-105.6%, 0.5%-36.0%, 0.8%-30.5%, 3.5%-42.3%, and 2.4%-75.2% in the no-tillage treatments, respectively; and the contents of SOC, ROC, DOC, water-soluble Ca and Mg increased by 29.2%-145.1%, 1.3%-63.9%, 2.4%-55.6%, 18.2%-89.8%, and 10.1%-150.5% in the ploughing treatment, respectively, under different dosage biochar amendments, and was enhanced with an increase in the biochar application amount. Cumulative CO2 emissions were highest with biochar amendment at 5 g·kg-1 under the no-tillage soil condition; however, this increased with an increase in the biochar amount in the ploughing treatment. At the end of incubation experiment, the soil MBC content increased by 35.5%-45.7% compared with the control treatment; however, there was no significant effect on soil pH and SIC between the treatments. â¡ Compared with the ploughing treatment, the cumulative CO2 emissions, SOC, ROC, DOC, MBC, and water-soluble Ca and Mg contents of the no tillage treatment increased by 34.2%-79.0%, 8.9%-45.5%, 28.2%-73.9%, 40.4%-78.4%, 0.2%-131.7%, 8.7%-39.8%, and 0.3%-61.0%, respectively, while soil pH and SIC decreased by 0.08-0.17 unit and 2.4%-13.9%, respectively, under the same biochar amendment treatments. Overall, the addition of biochar significantly increased soil organic carbon, active organic carbon, soil water soluble calcium and magnesium content, and soil cumulative CO2 emissions, but no significant effect was observed on soil inorganic carbon content.
Calligonum mongolicum is one of the dominant species in the Taklimakan Desert highway shelterbelt, the litter of which plays an important role in carbon cycling. After litter addition, we carried out a laboratory incubation experiment to investigate the dynamics of soil CO2 emission, soil organic carbon (SOC), soluble organic carbon (DOC), pH, and electrical conductivity (EC) under the condition of salt water (SW) and fresh water (FW) with field water holding capacity of 25%, 50%, 75%, and 100%. The results showed that saline water irrigation had an inhibitory effect on soil CO2 emission. Under the four soil water content treatments, the cumulative CO2 emission of freshwater irrigation increased by 1.9%-29.1% compared with that of saline irrigation. Cumulative soil CO2 emissions increased with increasing soil water content. With litter addition, SOC decreased rapidly in the early stage, then gradually increased, and finally tended to be stable. The DOC contents of each treatment following the incubation increased by 41.3%-92.4% compared with that before the incubation. At the end of incubation, soil pH of each treatment increased by 0.20-0.35. The EC increased with the increases of soil water content. Under the four water content conditions and compared with the situation before the incubation, the EC values irrigated with SW increased by 0.11-0.79 mS·cm-1, while those with FW increased or decreased at the end of incubation. Cumulative soil CO2 emission was positively correlated with SOC, DOC, and pH, but not with soil water content. Both saline irrigation and lower water content could inhibit CO2 emission of aeolian sandy soil under litter addition, while EC was significantly affected by the quality of irrigation water and soil water content.
Carbon , Soil , Carbon Dioxide , Sand , Water
Green land is important carrier in cities. We investigated the effects of soil permeability improvement and purification of pollutants under different matrix composition amendments in Xixian New Area, Shaanxi Province. Six materials, including biochar, vermiculite, perlite, compost, polyacrylamide (PAM) and coir, were mixed with basic materials that were composed of soil and sand (volume ratio of 4:4), and then incubated for 30 days. We analyzed bulk density, saturated hydraulic conductivity, saturated moisture, and total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD), copper (Cu), zinc (Zn), cadmium (Cd) concentrations in pollutants. For biochar and compost with volume ratio of 0.5:1.5 (1) and 1:1 (2), 1%PAM application had the best effect on soil permeability (including bulk density, saturated hydraulic conductivity, and saturated moisture). The effect purification of TN and COD was better under the condition of biochar and compost (1) with 0.5% PAM amendment than that with 1% PAM amendment. Under biochar and compost (1) with 1%PAM treatment, the adsorption rate of Zn, Cd, Cu was 99.9%, 99.7%, and 97.2%, respectively. In general, biochar and compost (volume ratio of 0.5:1.5) with 1% PAM could be recommended as the media of the sponge city green land in Xixian New Area.
Composting , Environmental Pollutants , Soil Pollutants , Charcoal , Cities , Permeability , Soil
To evaluate the emission characteristics of carbon dioxide (CO2) and nitrous oxide (N2O) in the Loess Plateau, a field in situ study was conducted from July 2017 to July 2018 under two land-use types (15 year old apple orchard and wheat field) using static chamber-gas chromatographic techniques. Four treatments were conducted in this experiment as follows:apple orchard with fertilization (AF), apple orchard without fertilization (ACK), wheat field with fertilization (WF), and wheat field without fertilization (WCK). The results showed that CO2 and N2O emissions varied significantly with the season, and the emission peaks appeared after rainfall and fertilization. The cumulative amount of CO2 and N2O emissions from the AF treatment were 7.14% and 461.4% higher than that of the WF treatment, respectively. However, the cumulative amount of CO2 emissions under the ACK treatment was 10.41% lower than that of the WCK treatment, whereas the cumulative amount of N2O emissions was 109.5% higher than that of the WCK treatment. The N2O emission flux from the orchard was significantly positively correlated with soil temperature and moisture (P<0.01). The CO2 emission fluxes from the orchard and wheat field were significantly positively correlated with topsoil temperature (P<0.05) but were not correlated with topsoil moisture. Thus, the combination of field management and environmental factors affected soil CO2 and N2O emissions. The fertilizer regime and soil hydrothermal conditions were the main factors influencing the characteristics of CO2 and N2O emissions under different land-use types.
An incubated study was conducted to explore the effect of different manure application dosages (0%, 1%, 2%, and 4%, referred to as T0, T1, T2, and T4, respectively) on dynamic changes in the organic carbon fraction and aggregate stability of soil under different incubation times (120, 180, 240, 300, and 360 days). Soil organic carbon (SOC) and its fractions, such as light fraction organic carbon (LFOC), and polysaccharides, cellulose, water-soluble substance (WSS), fulvic acid carbon (FAC), humic acid carbon (HAC) content, and aggregate stability were measured. The results showed that SOC and its fractions were increased with increasing manure application rates. The SOC, LFOC, polysaccharides, cellulose, WSS, FAC, HAC contents and the HAC/FAC ratio increased by 15.3%-83.2%, 6.8-15.9 times, 8.5%-46.4%, 39.3%-122.6%, 35.7%-112.9%, 3.3%-46.9%, 42.5%-88.3%, and 28.5%-38.6% under T1-T4 treatments, respectively, compared to the T0 treatment at the end of the incubation period. With a longer period of incubation, the contents of SOC and HAC showed a decreasing trend, the LFOC increased first and decreased. The FAC content and the HAC/FAC ratio showed a fluctuation trend, but the content of polysaccharides showed an increasing trend. The application of manure decreased the content of >2 mm mechanically stable aggregates but increased the content of > 0.25 mm water stable aggregates in the soil. The mean weight diameter of water stable aggregate (WMWD) increased by 58.6%, while by the end of the incubation period, the percentage aggregate destruction rate (PAD) decreased by 22.2% under the T4 treatment compared to the T0 treatment. Correlation analysis showed that there was a significant correlation between SOC and its fractions, and between organic carbon fractions (except polysaccharides) and aggregate stability. Path analysis showed that the content of HAC and > 2 mm mechanically stable aggregate had a significant direct impact on the mean weight diameter of mechanically stable aggregate (DMWD) (P<0.05). Furthermore, the content of > 2 mm and < 0.25 mm water stable aggregates had a significant direct impact on the WMWD (P<0.01). The content of<0.25 mm water stable aggregates had a significant direct impact on the PAD (P<0.01), while the content of SOC and WSS had a significant indirect impact on the PAD via a direct effect on the content of<0.25 mm water stable aggregate (P<0.05).
In order to evaluate the effect of grazing on the mechanism for greenhouse gas emissions in the seasonal frozen soils for a typical steppe in Inner Mongolia, variations of N2O and CO2 concentrations in different soil layers were monitored by an in situ gas collection system. Three conditions were selected:ungrazed since 1979 (UG79), ungrazed since 1999 (UG99), and continuously grazed (CG). The results showed that the profile soil N2O and CO2 concentrations demonstrated a significant spatio-temporal distribution. â The average concentrations of CO2 in the soil profile of the three conditions were:CO2 in the growth period > in the freezing-thawing period > in the freezing period. The CO2 concentrations in the growing period were much higher than in the freezing-thawing period and freezing period. The CO2 concentration was the highest in the UG79, and the lowest was in the CG. The concentration of CO2 in different soil layers was ordered as 20 cm ≥ 50 cm ≥ 35 cm ≥ 10 cm ≥ 5 cm at the UG79 and UG99 sites, and 50 cm ≥ 35 cm ≥ 20 cm ≥ 10 cm ≥ 5 cm at the CG site. â¡ The spatial and temporal variation of N2O concentration in the soil profile was different from that of CO2. While the UG79 and UG99 sites showed a "single peak type" change, the CG site had a "bimodal" pattern. The N2O concentration of the three conditions increased sharply during the soil freezing-thawing period, and the N2O was also released weakly during the growing season at the CG site (P<0.05). The average N2O concentration of the CG was significantly higher than that of UG79 and UG99 (P<0.05). The results show that the concentration of N2O in different soil layers was ordered as follows:UG79:20 cm ≥ 50 cm ≥ 35 cm ≥ 10 cm ≥ 5 cm; CG:50 cm ≥ 35 cm ≥ 20 cm ≥ 10 cm ≥ 5 cm, and UG99:35 cm ≥ 50 cm ≥ 20 cm ≥ 10 cm ≥ 5 cm. The results concluded that grazing decreased the profiled soil CO2 concentration and increased N2O concentration, which provides a basis for the accurate estimation of greenhouse gas emissions in the seasonal frozen soil in grasslands.
In order to evaluate the effect of different treatments on yield and greenhouse gas emissions during the summer maize growing season, a two-year film mulching experiment was conducted in 2014 and 2015. In this experiment, the two main experimental factors were rainfed treatment (R) and irrigated treatment (I), and the secondary experimental factors included control treatment (CK), half film mulching treatment (HM), and full film mulching treatment (FM). The emissions of soil greenhouse gases (CO2, CH4, and N2O) were monitored using a static opaque chamber and chromatography method. Moreover, the greenhouse gas emissions intensity (GHGI) was used to evaluate the effect of carbon sequestration in different treatments. The results of this study showed that the yields of the RHM and RFM treatments did not differ significantly in 2014, but increased by 19.6% and 26.8%, respectively, in 2015 compared with that of RCK. The yield of IHM was not improved, and that of IFM significantly increased by 14.1% and 55.8% in 2014 and 2015, respectively, compared with that of ICK. The irrigated treatments only promoted CO2 emissions in 2015 (P<0.01), and all film mulching treatments (regardless of HM and FM treatments) had no effect on CO2 emissions under rainfed and irrigated conditions (P>0.05). Irrigated treatments had no effect on the absorption of CH4 (P>0.05), whereas the film mulching treatments had an inhibitory effect. Compared with values of RCK, the amount of seasonal N2O emissions for ICK showed a significant difference in 2015 with a decrease of 22.3%. Compared with values of RCK, the amounts of N2O emissions for RHM and RFM had no significant differences in 2014, but significantly decreased by 50.7% and 51.4% in 2015, respectively. Compared with ICK, IHM and IFM significantly decreased the amounts of N2O emissions by 47.5% and 54.2% in 2014, and by 9.6% and 52.2% in 2015, respectively. The GHGIs of RHM and RFM were significantly reduced by 60.1% and 61.7% in 2015, respectively, compared with values of RCK, and the GHGIs of IHM and IFM were significantly reduced by 39.7% and 53.2% in 2014, and reduced by 22.2% and 67.5% in 2015, respectively, compared with that of ICK. This means that the effect of FM on reducing GHGI was better than that of HM. It was also found that the significantly reduced GHGI in irrigated treatments may be attributed to the increased yields. Therefore, FM under irrigation conditions was recommended for summer maize for stabilizing the yield and reducing the GHGI.
Agriculture/methods , Greenhouse Gases/analysis , Plastics , Zea mays/growth & development , Carbon Dioxide/analysis , Methane/analysis , Nitrous Oxide/analysis , Seasons , Soil
Application of biochar (BC) is an important way to increase soil organic carbon sequestration. At the same time, the effect of BC on fractions and properties of soil humic substances is concerned. A laboratory experiment was conducted to study the influences of BC pyrolyzed at different temperatures on the composition and properties of humic substances. The modified method for the extraction and fractionation of humic substances was adopted in this work. The carbon (C) contents of Humin (Hu), Humic acids (HA), Fulvic acids (FA) were analyzed by the thermal oxidation of K2Cr2O7 and TOC analyzer, and the optical properties of HA and FA were measured by using spectrophotometer. The results showed that the increasing temperature (from 300 to 600â) decreased like-humic substances (LHS) from 10.93 g·kg-1 to 0.26 g·kg-1, while the structure of theLHS tended to be complicated. Compared with control treatment (CK), the addition of BC produced under 400â increased the contents of HA and FA (after 240 d incubation a lower FA content was found in treatments) and increased as BC application rate increased, after 360 d of incubation, BC300 and BC400 significantly increased by 69.93% and 48.75% for HA (P<0.05), while decreased by 1.35% and 5.19% for FA. Higher contents of HA and FA were found in soil samples amended with BC prepared at above 400â only during the initial period of 3-10 d of incubation and increased as BC application rate increased, at the end of the incubation, the contents of HA and FA significantly decreased by 34.38%, 44.48% in BC500 treatments and 42.84%, 49.27% in the BC600 treatments (P<0.05). During the incubation, the addition of BC significantly increased the contents of Hu (P<0.05), and the treatments amended with BC500 were the highest. The addition of BC decreased the relative contents of HA and FA, while increased the relative content of Hu, indicating that the proportion of relatively stable organic carbon in the soil was increased. The ratio of HA/FA (H/F) varied between 0.88 and 2.52 and increased with decreasing pyrolysis temperature and increasing BC application. A significantly lower color tonal coefficient (ΔlgK) and E4/E6 values in treatments amended with BC produced at temperatures above 400â, indicating that higher temperatures derived BC complicated the structure of soil humic substance, while an opposite rend was observed in treatments amended with BC produced at temperatures under 400â. Considering the improvement of the stability of organic carbon, when the BC products were applied to the Loutu soil, 500â was the optimal temperature for preparing apple-derived BC not only because it could significantly increase the content of inert soil organic carbon, but also improve the quality of the soil as a result of enhancing the degree of soil humification.
Carbon/chemistry , Charcoal , Humic Substances , Soil/chemistry , Temperature , Carbon Sequestration
In order to compare the differences in carbon sequestration and greenhouse gas mitigation between straw and straw-derived biochar amendment, a field experiment was conducted with simultaneous measurement of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emissions, crop yield, soil organic carbon (SOC) content and net global warming potential (NGWP) in a wheat-maize rotation cropping system from the loess plateau of China. Five treatments were included:control (no straw incorporation, no straw-derived biochar amendment and no fertilization, CK), fertilization (no straw incorporation and no straw-derived biochar amendment, F), straw with fertilization (wheat straw incorporated at 8 t·hm-2, FS), low straw-derived biochar (8 t·hm-2) with fertilization (FBlow) and high straw-derived biochar (16 t·hm-2) with fertilization (FBhigh). Wheat yield increased by 30.9%, 66.3% and 36.6% under FS, FBlow and FBhigh treatment, as compared to the F treatment, respectively. However, maize yield decreased by 14.1%, 18.0% and 24.6% under FS, CK and FBhigh treatment as compared to the F treatment, respectively. There was no significant difference between FBlow and F treatment. Annual CO2 emission increased by 60.2% under FS treatment, but decreased by 14.4% under FBhigh treatment as compared to the F treatment, respectively. Annual N2O emission decreased by 27.6% and 38.7% under FBlow and FBhigh treatment as compared to the F treatment, respectively. However, no significant difference was observed under straw application. Overall, the NGWP decreased by 24.13 and 58.44 t·hm-2 under FBlow and FBhigh treatment as compared to the F treatment, respectively. And the NGHGI decreased by 1.78 and 5.06 t·t-1 under FBlow and FBhigh treatment as compared to the F treatment, respectively. In summary, we conclude that the fertilization with 16 t·hm-2 biochar amendment can be used as an effective management to improve the crop yield and reduce the net global warming potential under the wheat-maize rotation system.
Agriculture/methods , Charcoal , Triticum/growth & development , Zea mays/growth & development , Carbon Dioxide/analysis , China , Ecosystem , Global Warming , Methane/analysis , Nitrous Oxide/analysis , Soil
Soil active organic carbon is the most important carbon pool and a good indicator in ecosystem management due to its great significance in soil carbon cycling and soil quality.In order to investigate the effect of biochar (BC) addition on soil organic matter fractions,apple tree twigs were used to produce BC at 300,400,500 and 600â,respectively.Elemental analysis and Fourier transform infrared (FTIR) spectroscopy were used to determine the characteristics of BC.Four kinds of BC were added into soils at five application rates (0,0.5%,1%,2% and 3%) and incubated at 25â in lab for over 360 days.Soil organic carbon (SOC),microbial biomass carbon (MBC),water soluble organic carbon (WSOC) and readily oxidized organic carbon (ROC) were measured during the incubation.The mass fraction of carbon (C) in the generated BC ranged from 62.20%-80.01%,while hydrogen (H) ranged from 2.72%-5.18% and Oxygen (O) ranged from 15.98%-30.92%.The increasing temperature increased the mass fraction of C,while decreased the O and H mass content,as well as the ratio of H/C and O/C.The addition of BC significantly increased SOC,and the treatments amended with BC500 had the highest increments.Compared with the control treatment (CK),the addition of BC produced at temperatures below 400â increased the contents of MBC,WSOC and ROC during the incubation,at the end of the incubation,BC300 treatments significantly increased the contents by 38.25%,82.09% and 63.53%(P<0.05),respectively;BC400 treatments significantly increased the contents by 26.07%,65.61% and 48.09%(P<0.05),respectively;while lower contents of MBC,WSOC and ROC were found in the treatments amended with BC produced at temperatures above 400â after 40-60 d incubation.After 360 d of incubation,the contents of MBC,WSOC and ROC were significantly decreased by 0.27%,13.48% and 14.67% in BC500 treatments and 7.80%,14.66% and 15.79% in BC600 treatments (except for the MBC in BC500 treatment)(P<0.05).The relative contents of ROC ranged from 3.39% to 15.65%,BC application decreased the relative content of ROC,suggesting that the increase was in proportion to the stability of organic carbon in the soil.Considering the content and quality of SOC,when the BC products were applied to the Loutu soil,500â was the optimal temperature for preparing apple-derived BC due to its significant increase of the soil organic carbon and a slight decrease of the relative content of soil active organic carbon.
Carbon/analysis , Charcoal , Soil Microbiology , Soil/chemistry , Temperature
Irrigation can influence greenhouse gas (GHG) emission and carbon footprint in agricultural production. In this study, annual GHG emissions (including CO2, CH4, and N2O) were monitored with static opaque chamber and gas chromatography from a wheat-maize rotation system under different irrigation treatments in the Guanzhong Plain of China during 2014-2015. A total of four different irrigation treatments were conducted, e.g. W0, W120, W180, and W240, where the subscripts represented the irrigation amounts in mm. Net global warming potential (NGWP) and carbon footprint were used to evaluate the influence of different irrigation amounts on GHG emission and composition of carbon footprint of crop production. Compared with treatment W0, wheat yield of treatments W120, W180, and W240 increased by 31.3%, 44.3% and 33.7%, while corn yield increased by 9.9%, 22.6%, and 33.8%, respectively. Similarly, annual CO2 emission increased by 22.2%, 24.3% and 15.1% and annual N2O emission by 18.6%, 67.8%, and 91.5%, respectively, while annual CH4 absorption decreased by 51.7%, 79.6% and 97.8%, respectively. The values of NGWP increased by 20.1%, 31.6%, and 31.4%, respectively. The carbon footprint of treatment W120 was 19.1% lower than that of W0, while W180 and W240 showed no significant difference. Treatments W120 and W240 increased carbon footprint per unit crop yield by 44.5% and 23.3%, respectively, while W180 showed no significant difference. Considering both the economic and environmental effects of different irrigation amounts, we recommend the irrigating amount of 180 mm for the wheat-maize rotation system in the Guanzhong Plain of China for the purposes of water saving and carbon sequestration.
Carbon Sequestration , Triticum , Zea mays , Agriculture , China , Greenhouse Effect , Methane , Nitrous Oxide , Rotation
