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1.
Huan Jing Ke Xue ; 45(7): 4023-4031, 2024 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-39022950

ABSTRACT

Nitrogen loss from rice systems is an important source of agricultural non-point source pollution. Many studies revolve around reducing the rate of nitrogen fertilizer application. However, studies examining the characteristics of nitrogen loss in multiple loss paths (runoff, leaching, and lateral seepage) under different straw and fertilizer managements are lacking. Therefore, a study was carried out based on a rice field planted for more than 20 years with straw continuously returned to the field for more than 5 years in Taihu lake basin. The effects of straw and fertilizer managements on nitrogen loss in different paths during the whole growth period of rice were studied. Moreover, straw and fertilizer managements were evaluated by their production suitability and environmental friendliness based on crop yield, nitrogen use efficiency, and nitrogen loss. The results showed that straw removal from the field increased the response sensitivity of nitrogen accumulation in plant tissue to nitrogen application. The nitrogen loss in the rice season was 9-17 kg·hm-2, accounting for 5%-7% of the nitrogen application rate. Straw removal increased the risk of nitrogen loss when soaking water discharged. Straw returning could decrease the nitrogen loss by more than 15%, though the effect of straw on nitrogen loss via lateral seepage was not clear. Furthermore, the suitable substitution of organic fertilizer (30% in this study) could respectively reduce the amount of nitrogen loss via runoff, leaching, and lateral seepage by 16%, 26%, and 37% compared with the fertilizer application under the same nitrogen gradient. In conclusion, the implementation of straw returning and fertilizer type optimization measures effectively reduced the nitrogen loss for unit weight of rice production and realized the balance between agricultural production and environmental protection.


Subject(s)
Fertilizers , Lakes , Nitrogen , Oryza , Plant Stems , Oryza/growth & development , Oryza/metabolism , Nitrogen/metabolism , China , Plant Stems/metabolism , Plant Stems/growth & development , Plant Stems/chemistry , Agriculture/methods , Fragaria/growth & development , Fragaria/metabolism
2.
Medicine (Baltimore) ; 102(50): e36511, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38115268

ABSTRACT

Exercise rehabilitation can improve the prognosis of patients with coronary heart disease. However, a bibliometric analysis of the global exercise rehabilitation for coronary heart disease (CHD) research topic is lacking. This study investigated the development trends and research hotspots in the field of coronary heart disease and exercise rehabilitation. CiteSpace software was used to analyze the literature on exercise therapy for CHD in the Web of Science Core Collection database. We analyzed the data of countries/institutions, journals, authors, keywords, and cited references. A total of 3485 peer-reviewed papers were found, and the number of publications on the topic has steadily increased. The most productive country is the USA (1125), followed by China (477) and England (399). The top 3 active academic institutions are Research Libraries UK (RLUK) (236), Harvard University (152), and the University of California System (118). The most commonly cited journals are Circulation (2596), The most commonly cited references are "Exercise-based cardiac rehabilitation for coronary heart disease" (75), Lavie CJ had published the most papers (48). World Health Organization was the most influential author (334 citations). The research frontier trends in this field are body composition, participation, and function. Research on the effects of physical activity or exercise on patients with CHD is a focus of continuous exploration in this field. This study provides a new scientific perspective for exercise rehabilitation and CHD research and gives researchers valuable information for detecting the current research status, hotspots, and emerging trends for further research.


Subject(s)
Cardiac Rehabilitation , Coronary Disease , Humans , Exercise Therapy , Exercise , Bibliometrics
3.
Heliyon ; 9(7): e17908, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37483732

ABSTRACT

Renal fibrosis (RF) is a common pathological feature of chronic kidney disease (CKD), which remains a major public health problem. As now, there is still lack of chemical or biological drugs to reverse RF. Shen-shuai-yi Recipe (SSYR) is a classical Chinese herbal formula for the treatment of CKD. However, the effects and mechanisms of SSYR in treating RF are still not clear. In this study, the active constituents SSYR for treating RF were explored by UHPLC-Q-Orbitrap HRMS. Bioinformatics analyses were employed to analyze the key pharmacological targets and the core active constituents of SSYR in the treatment of RF. In experimental validation, vehicle or SSYR at doses of 2.12 g/kg/d and 4.25 g/kg/d were given by orally to unilateral ureteric obstruction (UUO) mice. 13 days after treatment, we detected the severity of renal fibrosis, extracellular collagen deposition and pre-fibrotic signaling pathways. Bioinformatics analysis suggested that signal transducer and activator of transcription 3 (STAT3) was the core target and lenticin, luteolin-7-O-rutinoside, hesperidin, kaempferol-3-O-rutinoside, and 3,5,6,7,8,3',4'-heptamethoxyflavone were the key constituents in SSYR for treating RF. SSYR significantly reduced the expressions of fibronectin (FN), α-smooth muscle actin (α-SMA), collagen-I and alleviated renal interstitial collagen deposition in UUO kidneys. In mechanism, SSYR potently blocked the phosphorylation of STAT3 and Smad3 and suppressed the expression of connective tissue growth factor (CTGF). Collectively, SSYR can ameliorate RF via inhibiting the phosphorylation of STAT3 and its downstream and reducing the collagen deposition, suggesting that SSYR can be developed as a novel medicine for treating RF.

4.
Huan Jing Ke Xue ; 44(7): 3902-3912, 2023 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-37438289

ABSTRACT

The intensity of crop farming fertilizer input is generally high in the Taihu Lake Region, with chemical fertilizer as the main form. Due to inappropriate fertilizer application, nitrogen and phosphorus loss have occurred, causing serious agricultural non-point source pollution. The Ministry of Agriculture and Rural Affairs of China has launched the "zero-growth action for chemical fertilizer use" and "replacement action with organic fertilizer" ("two actions" for short) campaigns since 2015. Local agricultural sectors adjusted fertilizer application strategies of crop farming to respond to the call of two actions. However, the current research is still focusing on reducing the total amount of fertilizer application and increasing the area of organic fertilizer application, which is mainly based on grain crops. The study of agricultural environment problems is still lacking, especially in vegetable, orchard, and tea systems. Therefore, a study was carried out in the typical agricultural area of Suzhou City Wuzhong District from 2019 to 2021. Based on the data of the amount of nitrogen and phosphorus removal by harvest crops and soil nitrogen and phosphorus residual in paddy, vegetable, orchard, and tea systems, the loss was estimated. The responses of nitrogen and phosphorus loss from typical crop systems to fertilizer application strategy adjustments were studied through analysis of different factors. The results showed that fertilizer application rate was the key to control nitrogen and phosphorus loss. Additionally, the suitable replacement ratio of organic fertilizer could further reduce the loss risk. It should be noted that the urgent demand for nutrients in crop growth should be considered to determine the timing of organic fertilizer application, and agricultural machinery should be used to assist organic fertilizer application to reduce labor output if possible. Fertilizer efficiency was the core of environmental friendliness and economic benefits of crop farming. Hence, improving fertilizer efficiency should be the guidance of fertilizer application strategy adjustment. Our suggestions on the adjustment of fertilizer application strategy in different crop systems in the study area are as follows:attention should be paid to the nitrogen, phosphorus, and potassium input ratio in paddy systems to further reduce nitrogen and phosphorus loss. Planting structure adjustment should be emphasized in vegetable systems to promote fertilizer efficiency. The strategy to satisfy both tea and orchard growth from a composite system perspective would help to build crop systems that meet the needs of green agricultural development.


Subject(s)
Fertilizers , Lakes , Crops, Agricultural , Nitrogen , Phosphorus , Tea
5.
Huan Jing Ke Xue ; 44(3): 1553-1561, 2023 Mar 08.
Article in Chinese | MEDLINE | ID: mdl-36922216

ABSTRACT

Farmland is the important soil carbon pool of terrestrial ecosystems and organic nutrient pool for crop growth. To clarify the impact of climate warming on the soil carbon pool, this study analyzed the effects of warming and fertilization on soil organic carbon and its labile components under rice-wheat rotation using a free-air temperature increase system. The variation in soil carbon pool management index (CPMI) was also evaluated. The results showed that the combined effects of warming and fertilization on soil organic carbon content and labile organic carbon components were insignificant. Warming increased the soil organic carbon (SOC) content, and the differences between warming and the ambient control in total organic carbon (TOC) and recalcitrant organic carbon (ROC) reached a statistically significant level. Compared with those under the ambient control, the contents of TOC, ROC, and labile organic carbon (LOC) subjected to warming increased by 7.72%, 7.42%, and 10.11%, respectively. The increased microbial biomass carbon (MBC) content (20.4%) and decreased particulate organic carbon (POC) content (36.51%) may have been the main reason for the variation in SOC. Warming showed no significant effect on soil dissolved organic carbon (DOC) content, whereas it markedly reduced its soluble microbial by-product components (41.89%). The results also showed that fertilization had no significant effect on soil TOC, ROC, and LOC, but it notably reduced the contents of DOC and POC and increased the MBC content. Compared with those under the control without fertilization, the contents of DOC and POC subjected to fertilization decreased by 35.44% and 28.33%, respectively, and the MBC content increased by 33.38%. Additionally, fertilization tended to increase the anthropogenic humus component (5.13%) and soluble microbial by-product component (29.41%) in dissolved organic matter and reduce the terrestrial humus component (13.33%). Warming and fertilization both tended to improve soil CPMI. Affected by SOC and LOC, the increase in soil carbon pool index and soil lability index were the main reason for the increase in soil CPMI under warming and fertilization, respectively. Overall, the results revealed that climate warming can affect the soil carbon pool by changing soil labile carbon components, which are not affected by fertilization.


Subject(s)
Oryza , Soil , Carbon , Triticum , Ecosystem , Fertilization , Agriculture/methods
6.
Huan Jing Ke Xue ; 44(1): 473-481, 2023 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-36635835

ABSTRACT

Clayey soil seriously affects water-holding capacity and nutrient movement. Adopting appropriate agronomic measures to optimize the distribution of soil inorganic nitrogen (SIN) and reduce the nitrogen (N) loss in this soil is the key to agricultural sustainable development. To clarify the effect of deep fertilization of slow/controlled release fertilizer with sowing on N loss in a clayey soil wheat field, two types of fertilizers, conventional fertilizer (CN) and slow/controlled release fertilizer (RCU), were selected in this study. Here, we evaluated the effects of these two fertilizer types on wheat yield, seasonal N runoff loss, ammonia volatilization, and N2O emissions in wheat fields in two typical fertilization modes (manual surface sowing and spreading (B) and belowground fertilization of slow/controlled release urea with mechanized strip sowing (D)). The temporal and spatial distribution characteristics of SIN in topsoil were also analyzed. The results showed that under the same fertilizer type, the wheat yield of D treatment was significantly higher than that of B treatment, whereas the yield of RCU was notably higher than that of CN under the same fertilization mode. D-RCU achieved the highest yield of 6.97 t·hm-2. The seasonal N losses from runoff and ammonia volatilization were higher than that from N2O emissions, and the responses of different N loss pathways to fertilizer types and fertilization methods were diverse. Fertilizer type and runoff occurrence time were the main influencing factors of N runoff loss, and N runoff loss of the RCU treatment was higher in the non-fertilization period. Unfortunately, affected by annual rainfall pattern, the seasonal N runoff loss of the RCU treatment (20.35 kg·hm-2) was significantly higher than that of the CN treatment (10.49 kg·hm-2). The late growth period was the main phase of ammonia volatilization, and the later period was jointly affected by fertilization modes and fertilizer types. The B-CN treatment induced the highest seasonal ammonia volatilization (18.15 kg·hm-2), which was significantly higher than that of the other treatments (7.31-8.38 kg·hm-2). Additionally, the D-RCU treatment (2.41 kg·hm-2) tended to reduce the N2O emissions in comparison to that in the B-CN treatment (4.02 kg·hm-2). The results also indicated that the horizontal movement of SIN was higher than the vertical movement. Deep fertilization of RCU was conducive to optimizing the spatial and temporal distribution of SIN, which was the main reason for the increase in wheat yield and the control of N loss from wheat fields. These results suggest that RCU is a suitable alternative fertilizer for increasing yield and reducing N loss in clayey soil wheat fields; D-RCU can increase the wheat yield and reduce ammonia volatilization and N2O emissions in wheat fields by optimizing the spatial and temporal distribution of SIN, and its increasing effect on N runoff loss in the non-fertilization period deserves attention.


Subject(s)
Fertilizers , Soil , Fertilizers/analysis , Triticum , Clay , Ammonia/analysis , Delayed-Action Preparations , Agriculture/methods , Nitrogen , Nitrous Oxide/analysis
7.
Front Pharmacol ; 13: 1016552, 2022.
Article in English | MEDLINE | ID: mdl-36313366

ABSTRACT

Liver fibrosis is a common pathological process of all chronic liver diseases. Hepatic stellate cells (HSCs) play a central role in the development of liver fibrosis. Cyclin-dependent kinase 9 (CDK9) is a cell cycle kinase that regulates mRNA transcription and elongation. A CDK9 inhibitor SNS-032 has been reported to have good effects in anti-tumor. However, the role of SNS-032 in the development of liver fibrosis is unclear. In this study, SNS-032 was found to alleviate hepatic fibrosis by inhibiting the activation and inducing the apoptosis of active HSCs in carbon tetrachloride-induced model mice. In vitro, SNS-032 inhibited the activation and proliferation of active HSCs and induced the apoptosis of active HSCs by downregulating the expression of CDK9 and its downstream signal transductors, such phosphorylated RNA polymerase II and Bcl-2. CDK9 short hairpin RNA was transfected into active HSCs to further elucidate the mechanism of the above effects. Similar results were observed in active HSCs after CDK9 knockdown. In active HSCs with CDK9 knockdown, the expression levels of CDK9, phosphorylated RNA polymerase II, XIAP, Bcl-2, Mcl-1, and ɑ-SMA significantly decreased, whereas those of cleaved-PARP1 and Bax decreased prominently. These results indicated that SNS-032 is a potential drug and CDK9 might be a new prospective target for the treatment of liver fibrosis.

8.
Journal of Clinical Hepatology ; (12): 334-341, 2022.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-920880

ABSTRACT

Objective To investigate the intervention effect of GDC-0449, a hedgehog signaling pathway inhibitor, on rats with liver fibrosis induced by carbon tetrachloride (CCl 4 ) combined with 2-acetylaminofluorene (2-AAF). Methods A total of 18 female Fisher344 rats were randomly divided into normal group, CCl 4 /2-AAF group, and GDC-0449 group, with 6 rats in each group. The rats in the CCl 4 /2-AAF group and the GDC-0449 group were given subcutaneously injected 30% CCl 4 -olive oil solution at a dose of 2 mL/kg twice a week for 6 weeks to induce liver fibrosis; since week 7, in addition to the injection of CCl 4 -olive oil solution, the rats in these two groups were given 2-AAF (100 mg/kg/d) by gavage, and the rats in the GDC-0449 group were given GDC-0449 (25 mg/kg/d) by gavage, while those in the normal group were given an equal volume of olive oil solution by injection and normal saline by gavage. All rats were sacrificed at the end of week 9, and related samples were collected. HE staining and sirius red (SR) staining were used to observe the changes in liver histopathology and collagen deposition, and the semi-quantitative analysis of SR-positive area and Ishak score were used to evaluate fibrosis degree; the alkaline hydrolysis method was used to measure the level of hydroxyproline (Hyp) in liver tissue; immunohistochemistry, Western blot, and qRT-PCR were used to measure the expression of α-smooth muscle actin (α-SMA), type Ⅰ collagen (Col-Ⅰ), type Ⅳ collagen (Col-Ⅳ), cytokeratin 19 (CK19), cytokeratin 7 (CK7), the epithelial cell adhesion molecule Epcam, and the hedgehog signaling pathway in liver tissue; double immunofluorescence staining was used to observe the colocalization of CK19 and the oval cell marker OV6. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t -test was used for further comparison between two groups. Results Compared with the normal group, the CCl 4 /2-AAF group had marked inflammatory cell aggregation and collagen deposition in liver tissue, with the formation of a pseudolobular structure, as well as significant increases in Hyp level and collagen positive area ratio in liver tissue ( P < 0.05), Ishak score ( P < 0.05), and the expression of α-SMA, Col-Ⅰ, Col-Ⅳ, Epcam, CK19, CK7, the transmembrane transporter Smoothened (Smo), Hedgehog ligand Desert Hedgehog (Dhh), the Indian Hedgehog membrane-binding receptor Patched (Ptch2), and glioma-related oncogenes Gli1, Gli2, and Gli3 (all P < 0.05); double immunofluorescence staining showed that CK19-positive cells also expressed OV6 in the liver tissue of rats in the CCl 4 /2-AAF group, with a significant increase compared with the normal group. Compared with the CCl 4 /2-AAF group, the GDC-0449 group had significant reductions in inflammatory cell aggregation and collagen deposition in liver tissue, Hyp level and collagen positive area ratio in liver tissue ( P < 0.05), Ishak score ( P < 0.05), and the expression of α-SMA, Epcam, CK19, CK7, Smo, Ptch2, Gli1, Gli2, and Gli3 (all P < 0.05); double immunofluorescence staining showed a significant reduction in the number of cells with co-expression of OV6 and CK19 in liver tissue. Conclusion The Hedgehog signaling pathway inhibitor GDC-0449 can significantly inhibit the progression of liver fibrosis induced by CCl 4 /2-AAF in rats, possibly by inhibiting hepatic stellate cell activation, collagen deposition, activation and proliferation of hepatic progenitor cells, and differentiation of hepatic progenitor cells into biliary epithelial cells.

9.
Huan Jing Ke Xue ; 42(7): 3451-3457, 2021 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-34212672

ABSTRACT

Hydrochar can mitigate ammonia volatilization when applied in paddy fields due to its acidity and adsorption property. To realize the recycling of agricultural biowaste as well as the control of nutrient loss from paddy fields, a simulation soil-column experiment with wheat straw hydrochar (WHC) and water-washed hydrochar (W-WHC) was conducted to evaluate the performance of rice yield and ammonia volatilization from paddy fields. The results showed that WHC and W-WHC applied in paddy fields both increased the rice yield and the increased effect at low application rate (0.5%) was higher than that at high application rate (1.5%). In comparison with the control treatment (CKU), the rice yields achieved from low application rate treatments for WHC and W-WHC increased by 17.16% and 20.20% respectively. Except for the equal emission rate between W-WHC with low application rate and CKU treatments, hydrochar (WHC, W-WHC) addition reduced the ammonia volatilization from paddy fields when compared with the CKU. Among them, the ammonia volatilization levels from low-application WHC and high-application W-WHC treatments were significantly lower than that from the CKU treatment, reduced by 31.01% and 17.40%, respectively. Based on the analysis of ammonia volatilization during different fertilization stages, the control effect of hydrochar addition on ammonia volatilization was mainly benefited from tillering and panicle fertilizer stages. The change in the nitrogen concentration of surface water at the tillering fertilizer stage and in pH at the panicle fertilizer stage with the addition of hydrochar was the main driving factor for the reduction in ammonia volatilization. The results show that sufficient amounts of hydrochar derived from wheat straw application can increase crop yield while reducing ammonia volatilization from paddy fields. This method provides an effective route for recycling agricultural biowastes.


Subject(s)
Ammonia , Oryza , Ammonia/analysis , Fertilizers/analysis , Nitrogen/analysis , Soil , Triticum , Volatilization
10.
Ying Yong Sheng Tai Xue Bao ; 32(3): 942-950, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33754560

ABSTRACT

The strategy of few or no-phosphorus fertilization in rice season but more in wheat season can effectively increase phosphorus use efficiency and reduce phosphorus loss through runoff and leaching. It remains unknown whether the lack of phosphorus will affect greenhouse gas emission in the rice season. We monitored the CH4 and N2O emission fluxes during the growth period of rice treated with normal phosphorus application (NPK) and no-phosphorus application (NK) in two long-term experimental fields in Suzhou and Yixing. The results showed that long-term no-phosphorus application promoted CH4 and N2O emission in both fields. Compared with the NPK treatment, CH4 and N2O emissions from the NK treatment significantly increased by 57% and 25% in Suzhou experi-mental field, respectively, while those in Yixing experimental field were also significantly increased by 221% and 70%, respectively. The contents of organic acid, dissolved organic carbon and available phosphorus in soil were reduced under long-term NK treatment, and they were closely related to CH4 emission. Soil available phosphorus content was significantly negatively correlated with CH4 emission (r=-0.987). The global warming potential (GWP) was greater in NK treatment than NPK treatment in both fields. Therefore, long-term no-phosphorus application could decrease the contents of organic acid, soluble organic carbon, and available phosphorus in soils, resulting in more CH4 and N2O emission in rice field.


Subject(s)
Greenhouse Gases , Oryza , Agriculture , China , Fertilization , Fertilizers , Greenhouse Gases/analysis , Methane/analysis , Nitrous Oxide/analysis , Phosphorus , Soil
11.
Huan Jing Ke Xue ; 42(1): 477-484, 2021 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-33372501

ABSTRACT

Ammonia volatilization emissions constitute the main pathway of nitrogen loss from paddy systems. Present control technologies are based on reducing the amount of nitrogen fertilizer applied. However, ratio of nitrogen loss through ammonia volatilization emissions has not changed, and it has become a bottleneck for promoting nitrogen use efficiency. Therefore, in order to study the effects of film materials on ammonia volatilization emissions, a two-year field plot experiment was carried out with agricultural waste powder and amphipathic molecule materials spread on surface water after nitrogen fertilizer application in paddy system. The results showed that film materials could reduce nitrogen loss through ammonia volatilization by 19%-31% in the paddy season, and this part of nitrogen was accumulated in soil or assimilated by paddy tissue. The ammonium concentration and pH in the surface water and film materials were the major control factors of ammonia volatilization emissions with nitrogen fertilizer application. Moreover, further reductions in ammonia volatilization emissions could be achieved by film materials after reducing nitrogen fertilizer application. Differences in the effect mechanisms of the film materials provide flexible options for practical agricultural production to meet demands.

12.
Article in English | WPRIM (Western Pacific) | ID: wpr-934868

ABSTRACT

@#In the context of the global pandemic of COVID-19, with the epidemic epicenter located in the Wuhan City, China, patients with severe mental illness have also been deeply affected by the epidemic. In this paper, two patients with schizophrenia who recovered from COVID-19 were reported. Because of the long-term positive results of the SARS-CoV-2 serum antibody IgM test, they had to undergo medical isolation and social restrictions for a long time. After the situation was effectively identified by the medical staff and they were eliminated as a potential virus carrier and released from the medical isolation center. Since psychiatrists often lack systematic knowledge of infectious diseases, the authors hope that this paper can provide a reference to avoid unnecessary wastage of medical resources and prevent placing serious mental burden on such patients in the future.

13.
Huan Jing Ke Xue ; 41(12): 5648-5655, 2020 Dec 08.
Article in Chinese | MEDLINE | ID: mdl-33374082

ABSTRACT

Biochar application on farmlands is an efficient way to realize agricultural/forestry biowaste recycling in parallel with carbon sequestration. Recently, hydrochar produced by hydrothermal carbonization processes has attracted attention due to the advantages over conventional pyrolytic production (i.e., easier production process, higher carbon yield, reduced energy consumption, and lower flue gas emissions). To clarify the effects of hydrochar applied in farmlands on crop production, as well as to realize the recycling of agricultural/forestry biowaste resources, this study evaluated the effects of four types of modified-hydrochar addition on rice yield and nitrogen uptake in two typical soils and the possible influencing factors through soil-column experiments and material characterization. The results showed that sawdust hydrochar and/or straw hydrochar could increase rice yield and nitrogen uptake, as well as reduce N loss, in both treated soils after physical or biological modification, an effect that was independent of the application rate (5‰, 15‰; mass fraction). In comparison to the control, the rice yield and nitrogen uptake of hydrochar-addition treatments increased by 9.2%-20.7% and 7.7%-17.0% respectively. Sawdust hydrochar, with a wider C/N material, was conducive to improving nitrogen uptake in high fertility soils; meanwhile, the nitrogen utilization in low fertility soils was less affected by the type of hydrochar due to the limitations imposed by multiple factors. The results of material characterization showed that the surface of the hydrochar was rich in nutrients; the pore structure of hydrochar after washing or biological modification was greatly improved, the relative content of C was remarkably reduced, and the relative contents of N and O notably increased, which could affect nutrient fixation and supply. Thus, the improved pore structure and increased contents of N and O of modified hydrochars may be the key drivers for the increase in rice yield and nitrogen uptake with hydrochar addition. These results suggest that modified hydrochar is beneficial to realizing agricultural/forestry biowaste recycling and improving crop yield and nitrogen utilization, as well as reducing N loss from farmlands.


Subject(s)
Nitrogen , Oryza , Agriculture , Carbon , Soil
14.
Huan Jing Ke Xue ; 41(8): 3870-3878, 2020 Aug 08.
Article in Chinese | MEDLINE | ID: mdl-33124365

ABSTRACT

The contribution of crop planting to agricultural non-point source pollution should not be underestimated in China. Although many modern technologies have been developed to prevent non-point source pollution in recent decades, their impacts on pollution control in farmland are far from expectation. The application of technologies for non-point source pollution control for crop farming has been delayed due to unclear technical parameters and application effectiveness. Therefore, based on studies of the non-point source pollution control for crop farming in China and abroad that were published in the last 20 years, the present research was carried out to determine the development process of planting non-point source pollution control technologies and to illuminate the framework construction. The technologies in different fields and directions were compared by their effects on fertilizer input,yield, and pollutant emission. The development trend in the field of prevention and control technologies for planting non-point source pollution was subsequently predicted. In addition, a technical framework was developed with 3 fields (pollutant source reduction, pollutant interception in the migration process, and nutrient recycling) and 14 directions. The analysis showed that the technologies for reducing pollutants from the source have attracted the most (and increasing) concern with many research directions, and that many of the studies in this field have focused on the regulation of fertilizer application. On the contrary, there is a lack of technologies in the fields of pollutant process interception and nutrient recycling. Promoting nutrient-use efficiency, regulating nutrient transformation, and using soil supplements will be the main entry points for non-point source pollution control for crop farming. Furthermore, technologies will operate better with the help of farmland infrastructure and downstream purification systems.


Subject(s)
Non-Point Source Pollution , Agriculture , China , Fertilizers , Nitrogen/analysis , Phosphorus/analysis
15.
Huan Jing Ke Xue ; 41(2): 773-783, 2020 Feb 08.
Article in Chinese | MEDLINE | ID: mdl-32608737

ABSTRACT

Lanthanum (La)-based materials have shown great potential for phosphate removal owing to the strong affinity between La and phosphate. In this study, magnetic hydrothermal biochar immobilized La(OH)3 (La-MHTC) were prepared and used as phosphate adsorbents. Hydrochar was produced by the hydrothermal carbonization process (220℃, 2 h). Magnetic La-MHTC with different La-to-Fe mass ratios were synthesized by the co-precipitation method. Subsequently, La-MHTC was applied to remove phosphate from wastewater. Results indicate that La-MHTC (with a La-to-Fe mass ratio of 2:1) exhibited excellent magnetic properties for easy recovery and high phosphate adsorption capacity up to 100.25 mg·g-1. Effective phosphate removal was obtained over a wide pH range of 3-10. The absorption isotherm and kinetics were better fitted by the Langmuir model and the pseudo second-order model, respectively, which showed a fast adsorption rate and exhibited superior La utilization efficiency. The La-MHTC has strong selectivity for phosphate in the presence of coexisting ions (Cl-, NO3-, and SO42-). The adsorption-desorption experiment suggested its excellent stability and cyclic utilization. In addition, La-MHTC was applied to treat real domestic wastewater, efficiently reducing the phosphate concentration (from 0.87 mg·L-1 to 0.05 mg·L-1). Electrostatic attraction and inner-sphere complexation between La(OH)3 and P via ligand exchange were the main mechanisms of phosphate adsorption by La-MHTC.

16.
Huan Jing Ke Xue ; 41(2): 922-931, 2020 Feb 08.
Article in Chinese | MEDLINE | ID: mdl-32608754

ABSTRACT

Hydrochar, as a product of the hydrothermal carbonization of biomass, has good application prospects for the NH3 volatilization reduction in rice fields due to its rich pore structure and functional surface. In this study, hydrochar was applied as a soil conditioner to paddy soil. A soil column experiment was conducted to investigate the effect of hydrochar on NH3 volatilization throughout the growth period of rice. The experiment was conducted with three treatments:CKU (control without hydrochar); SHC (sawdust hydrochar); and W-SHC (water-washed sawdust hydrochar). The application rate of SHC and W-SHC was 0.5% (w/w). The study investigated the effects of different hydrochars on the pH and concentrations of NH4+-N in floodwater, the flux and accumulation of NH3 volatilization, and the yield-scale cumulative emission of NH3 volatilization. Results show that the SHC treatment significantly reduces cumulative emissions of NH3 volatilization and the yield-scale cumulative emissions of NH3 volatilization (P<0.05), which were 32.42% and 47.61% lower than CKU, respectively. The effect of W-SHC on ammonia volatilization reduction was slightly weaker, as the cumulative emissions of NH3 volatilization and the yield-scale cumulative emissions of NH3 volatilization decreased by 10.14% and 27.71%, respectively, compared with CKU. The NH3 volatilization reduction was possibly related to the disturbance of pH and the decrease in NH4+-N concentrations in the floodwater because of the application of hydrochar. Compared with CKU, both SHC and W-SHC treatments reduced the pH and NH4+-N concentration in the floodwater. The impacts were more obvious in the rice base fertilizer period (BF) and the first supplemental fertilizer period (SF1) than in the second supplemental fertilizer period (SF2). The soil urease activity was significantly inhibited by hydrochar (P<0.05), and the abundance of soil ammonia-oxidizing gene (AOA, AOB) also significantly increased after application of SHC (P<0.05). This resulted in the enhanced efficiency of ammonia-oxidizing, which had an effect on the reduction of the NH4+-N concentrations in the floodwater. This study provides theoretical and experimental data support for the application of hydrochar in agro-environments with regard to ammonia volatilization reduction in paddy fields.

17.
Huan Jing Ke Xue ; 40(8): 3746-3752, 2019 Aug 08.
Article in Chinese | MEDLINE | ID: mdl-31854784

ABSTRACT

Nitrification inhibitor and biochar are commonly used as soil synergists. Among them, nitrification inhibitor can increase crop yields and N use efficiency, while biochar is a relatively new way of using biomass resources and has certain adsorption characteristics. In order to reduce nitrogen loss and environmental pollution caused by ammonia volatilization in paddy fields, a pot experiment with chemical fertilizer application (CN) as a control was conducted to study the effects of biochar (B), nitrapyrin (CP), and compound application (BCP) on pH, NH4+-N concentration dynamics in the flood water, rice yields, and ammonia volatilization from paddy fields. The results showed that the application of these two synergists had no significant effect on rice yields, and the nitrification inhibitors had a tendency to increase rice yields. The two synergists significantly increased ammonia volatilization from paddy fields, accounting for 25%-35% of the total N rate. Ammonia volatilization during periods of fertilizer application accounted for 86%-91% of the total loss, representing the main period of ammonia volatilization. Compared with the CN treatment, the CP treatment increased NH4+-N concentrations in flood water and the loss of ammonia via volatilization, which was increased by 59.18% and mainly occurred during a week after the basal fertilization(138%) and spike fertilization (48%), and non-fertilization stage (78%). Biochar had a promoting effect on ammonia volatilization with typically phased characteristics. The initial increasing effect of biochar on ammonia volatilization was higher than during the later stages, when NH4+-N concentrations and the pH of flood water showed the same trend. In addition, the coupling of nitrification inhibitor and biochar significantly increased the total loss of ammonia via volatilization loss due to the promotion effect of CP and B. The problem of increased ammonia volatilization loss caused by the application of nitrification inhibitors requires further research.

18.
Can J Physiol Pharmacol ; 97(5): 345-351, 2019 May.
Article in English | MEDLINE | ID: mdl-29894643

ABSTRACT

We aimed to investigate whether the cardioprotection of sevoflurane against ischemia-reperfusion (IR) injury is via inhibiting endoplasmic reticulum stress. The rat in vivo model of myocardial IR injury was induced by ligation of the left anterior descending coronary artery. Sevoflurane significantly ameliorated the reduced cardiac function, increased infarct size, and elevated troponin I level and lactate dehydrogenase activity in plasma induced by IR injury. Sevoflurane suppressed the IR-induced myocardial apoptosis. The increased protein levels of glucose-regulated protein 78 and C/EBP homologous protein (CHOP) after myocardial IR were significantly reduced by sevoflurane. The protein levels of phosphorylated protein kinase RNA-like endoplasmic reticulum kinase (PERK), phosphorylated eukaryotic initiation factor 2 (eIF2α), and activating transcription factor 4 (ATF4) were significantly increased in rats with IR and attenuated by sevoflurane treatment. The phosphorylation of Akt was further activated by sevoflurane. The cardioprotection of sevoflurane could be blocked by wortmannin, a PI3K/Akt inhibitor. Our results suggest that the cardioprotection of sevoflurane against IR injury might be mediated by suppressing PERK/eIF2a/ATF4/CHOP signaling via activating the Akt pathway, which helps in understanding the novel mechanism of the cardioprotection of sevoflurane.


Subject(s)
Cardiotonic Agents/pharmacology , Endoplasmic Reticulum Stress/drug effects , Myocardial Reperfusion Injury/pathology , Myocardial Reperfusion Injury/prevention & control , Sevoflurane/pharmacology , Activating Transcription Factor 4/metabolism , Animals , Apoptosis/drug effects , Coronary Vessels/drug effects , Coronary Vessels/pathology , Eukaryotic Initiation Factor-2/metabolism , Heart/drug effects , Heart/physiopathology , Male , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/physiopathology , Myocardium/metabolism , Myocardium/pathology , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , eIF-2 Kinase/metabolism
19.
Huan Jing Ke Xue ; 39(11): 5170-5179, 2018 Nov 08.
Article in Chinese | MEDLINE | ID: mdl-30628242

ABSTRACT

Building a nutrient channel between eutrophic water and agricultural fields could reduce nutrient input into fields and alleviate eutrophication by returning nitrogen. In order to determine the feasibility of returning nitrogen by biochar loading, a rhizobox experiment was conducted with two nitrogen applied methods, namely SN (applied nitrogen by nitrogen fertilizer solution) and BN (applied nitrogen by nitrogen-loaded biochar). The results showed that BN, in comparison with SN, decreased the biomass and nitrogen uptake of the aboveground paddy by 16% and 14%, respectively, increased biomass root-shoot ratios by 25%-27%, and reduced nitrogen recovery use efficiency. Two nitrogen application methods affected the length and volume of paddy adventitious roots. Paddy underground biomass and nitrogen uptake were positively correlated with soil ammonium content, whereas paddy aboveground nitrogen uptake was negatively correlated with root tips. It was suggested that the paddy biomass and nitrogen uptake would be influenced when nitrogen was applied solely by nitrogen-loaded biochar. However, no affinity and no significance in nitrogen use efficiency were found for plant uptake between chemical nitrogen and biochar-loaded nitrogen. Additionally, biochar promoted soil mineral nitrogen content for further plant uptake. Therefore, biochar could be used as the carrier for returning nitrogen from waterbodies to fields. The replacement rate of chemical nitrogen fertilizer is the key to influencing plant growth and needs future study.


Subject(s)
Charcoal , Fertilizers , Nitrogen/metabolism , Oryza/growth & development , Plant Roots/growth & development , Soil/chemistry
20.
Huan Jing Ke Xue ; 38(12): 5326-5332, 2017 Dec 08.
Article in Chinese | MEDLINE | ID: mdl-29964597

ABSTRACT

In order to reduce the ammonia volatilization in paddy fields, seven treatments were evaluated. These included three slow-release nitrogen fertilizers[sulfur-coated urea (SCU); resin-coated urea (RCU); release bulk blending fertilizer (RBB)], two fertilization modes[single base fertilization (B) and combined with panicle fertilizer (BF)], and conventional split fertilization (CN). The effects of side deep fertilization for slow-release nitrogen fertilizers on ammonia volatilization and surface water nitrogen dynamics were examined using a rice transplanter with a fertilizer sowing mechanism in the Taihu Lake region. The results showed that total nitrogen and ammonium nitrogen concentration in the surface water of the SCU treatment in the base period were higher, and those for RCU and RBB were lower than in the CN treatment. The cumulative ammonia volatilization during the whole rice season varied among different types of slow-release nitrogen fertilizers from 3.84% to 28.17% of the total N applied. The nitrogen loss from ammonia volatilization using the three slow-release nitrogen fertilizers was decreased when compared with conventional split fertilization. The ammonia volatilization loss exhibited the following relationship for the treatments:CN, B-SCU > BF-SCU, BF-RBB, BF-RCU, B-RBB, and B-RCU. When the slow-release nitrogen fertilizers were applied in single base fertilization, the total ammonia volatilization for the SCU was significantly higher than those for the RCU and RBB, while no significant differences were detected when these three slow-release fertilizers were combined with panicle fertilizer. Moreover, although the ammonia volatilization of BF-SCU was lower than that of B-SCU, those of BF-RCU and BF-RBB were higher than those with the B-RCU and B-RBB treatments, respectively. There are no significant differences for nitrogen volatilization when any of these three different fertilizers are applied as B or BF. The results for the emissions during ammonia volatilization during different stages indicated that the ammonia volatilization of SCU at the basal-tillering fertilization stage (7.54%) and the tillering-panicle fertilization stage (16.04%) were higher than those of the panicle fertilization-mature stage. The N loss from ammonia volatilization for RBB in the base-tillering fertilization stage (2.91%) increased more than in the tillering-panicle fertilization stage and panicle fertilization-mature stage. For RCU treatment, the highest rate for ammonia volatilization was detected at the panicle fertilization-mature stage (2.75%). Compared with the single base fertilization mode, ammonia volatilization during the panicle fertilization-mature stage was increased when combined with panicle fertilizer (BF) for the slow-release fertilizer. There was no obvious correlation between the N loss with ammonia volatilization for the three slow-release nitrogen fertilizers and the concentration of ammonium nitrogen in surface water during the panicle fertilization-mature stage.


Subject(s)
Ammonia/metabolism , Fertilizers , Oryza/metabolism , Soil/chemistry , Agriculture , Nitrogen , Volatilization
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