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1.
Huan Jing Ke Xue ; 42(7): 3232-3241, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212649

RESUMO

To increase crops yields, applying large amounts of fertilizers has become increasingly common in agricultural regions, resulting in NO3--N groundwater pollution. Agricultural non-point pollution is the main source of groundwater NO3--N pollution. To ensure drinking water safety and quality, it is crucial to clarify the sources of NO3--N pollution in agricultural regions. In this study, 35 sampling sites were randomly selected in the Qingdao agricultural area in 2009 and 2019. The spatial distribution of NO3--N concentration was analyzed by the inverse distance weighting method (IDW). The nitrogen and oxygen isotopes were used as a tool to trace sources of NO3--N and the SIAR model was used to quantify contribution proportion of pollution sources. The results showed that the concentration of NO3--N (average) in groundwater in Qingdao has been reduced from 38.49 mg·L-1 in 2009 to 22.37 mg·L-1 in 2019, but it is still higher than the maximum allowable concentration of NO3--N in drinking water set by the World Health Organization (WHO). The NO3--N concentration gradually increased from south to north both in 2009 and 2019. The cross diagram of δ15N-NO3- and δ18O-NO3- show that the main sources of NO3--N in groundwater in Qingdao are chemical fertilizers, soil nitrogen, and manure and sewage. Water isotopes indicate that precipitation was the main source of groundwater in Qingdao. The SIAR model results indicated that the contribution of each source ranked as follows:manure and sewage (47.42%) > soil nitrogen (27.80%) > chemical fertilizer (14.32%) > atmospheric nitrogen depositions (10.43%). From 2009 to 2019, the quality of groundwater in Qingdao has been improved, but NO3--N pollution still cannot be ignored. According to the results, prevention and control should be made to ensure the safety of drinking water and the sustainable development of agriculture.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Agricultura , Monitoramento Ambiental , Fertilizantes/análise , Nitratos/análise , Isótopos de Nitrogênio/análise , Poluentes Químicos da Água/análise
2.
Huan Jing Ke Xue ; 42(7): 3442-3450, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212671

RESUMO

Based on Landsat satellite remote sensing images, this study interprets land use changes in the Yangtze River Delta (YRD) region from 2000 to 2018. Combined with changes in nitrogen fertilizer application, the changes in ammonia emissions from farmland ecosystem due changes in land use and nitrogen fertilizer application were further investigated. The results show that along with the rapid urbanization process, the area of cultivated land in the YRD region has gradually decreased from 276269 km2 (49% of total land area) in 2000 to 244001 km2 (44%) in 2018. The effects of changes in land use and nitrogen fertilizer application on ammonia emissions from farmland ecosystems mainly include emissions from soil background and nitrogen fertilizer application. From 2000 to 2018, ammonia emissions due to the application of nitrogen fertilizer decreased from 690 kt·a-1 to 541 kt·a-1 (relative decrease by 22%), while the ammonia emissions from the soil background reduced from 32 kt·a-1 to 29 kt·a-1 (decrease by 9%). During the past 20 years, urbanization in the YRD region has accelerated, and the area of cultivated land and the total amount of nitrogen fertilizer application have significantly reduced, thus resulting in reductions in ammonia emissions from the farmland ecosystem.


Assuntos
Amônia , Ecossistema , Agricultura , Amônia/análise , China , Fertilizantes/análise , Nitrogênio/análise , Rios , Solo
3.
Huan Jing Ke Xue ; 42(7): 3451-3457, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212672

RESUMO

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.


Assuntos
Amônia , Oryza , Amônia/análise , Fertilizantes/análise , Nitrogênio/análise , Solo , Triticum , Volatilização
4.
Huan Jing Ke Xue ; 42(7): 3458-3471, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212673

RESUMO

Paddy soils are widely considered a main source of methane (CH4) and nitrous oxide (N2O). Comprehensively evaluating CH4 and N2O emissions from double-rice systems in tropical regions with different water irrigation and fertilizer applications is of great significance for addressing greenhouse gas emissions from such systems in China. In this study, eight treatments were evaluated:conventional irrigation-PK fertilizer (D-PK), conventional irrigation-NPK fertilizer (D-NPK), conventional irrigation-NPK+organic fertilizer (D-NPK+M), conventional irrigation-organic fertilizer (D-M), continuous flooding-PK fertilizer (F-PK), continuous flooding-NPK fertilizer (F-NPK), continuous flooding-NPK+organic fertilizer (F-NPK+M), and continuous flooding-organic fertilizer (F-M). CH4 and N2O emissions in double-rice fields in tropical region of china were monitored in situ by closed static chamber-chromatography method and crop yields as well as global warming potential (GWP) and greenhouse gas intensity (GHGI) were determined. The results show that:① The cumulative CH4 emissions from early rice and late rice are 10.3-78.9 kg·hm-2and 84.6-185.5 kg·hm-2, respectively. Compared with F-PK and F-NPK treatments, F-NPK+M and F-M treatments significantly increased the cumulative emissions of CH4 from early rice season. Under the same fertilizer conditions, the cumulative CH4 emissions under continuous flooding condition were significantly higher than that under conventional irrigation condition. Irrigation and fertilization had extremely significant effects on CH4 emission in the early rice season. ② The cumulative N2O emissions across all treatments were 0.18-0.76 kg·hm-2 in early rice season and 0.15-0.58 kg·hm-2in late rice season, respectively. During early rice season, compared with F-PK, F-NPK significantly increased the cumulative N2O emission; however, compared with D-PK, D-NPK, D-NPK+M, and D-M treatments significantly increased the cumulative N2O emissions. Compared with F-PK, other three treatments under continuous flooding condition significantly increased N2O cumulative emission in late rice season; compared with D-PK, D-NPK, and D-M treatment significantly increased the cumulative N2O emission. Irrigation and fertilization had significant impacts on N2O emissions in late rice season, and fertilization had significant impacts on N2O emission in early rice season. ③ Early and late rice yields were 7310.7-9402.4 kg·hm-2 and 3902.8-7354.6 kg·hm-2, respectively. Early rice yields in both F-NPK and F-M treatments were significantly higher than those in F-PK, D-PK, and D-NPK treatments. Compared with PK, the other three fertilization treatments under the same irrigation condition significantly increased late rice yield. The GWP and GHGI in early rice season were 580.8-2818.5 kg·hm-2and 0.08-0.30 kg·kg-1, respectively. There was no significant difference in GWP among four fertilizer treatments under conventional irrigation condition in the early rice season. However, F-NPK+M and F-M treatments had a significant increase in GWP compared with F-PK. The GHGI in F-NPK+M and F-M treatments were significantly higher than that in other treatments. The GWP and GHGI in late rice season were 3091.6-6334.2 kg·hm-2 and 0.50-1.23 kg·kg-1, respectively. Irrigation significantly affected GWP and GHGI in both early and late rice seasons but fertilization had no significant impact on GWP and GHGI in late rice season. ④ Correlation analysis results showed that soil NH4+-N content and soil temperature below 5 cm soil layer had an extremely significant negative correlation with CH4 emissions. Soil pH was extremely significant positive correlated with CH4 emissions but significantly negatively correlated with N2O emission. Soil NH4+-N and NO3--N concentrations were extremely significantly negatively correlated with N2O emission. Given crop yield, GWP, GHGI, and D-NPK+M can be recommended for local water and fertilizer management to reduce greenhouse gas emissions while maintaining rice yields.


Assuntos
Oryza , Agricultura , China , Fertilização , Fertilizantes/análise , Metano/análise , Óxido Nitroso/análise , Solo , Água
5.
Sensors (Basel) ; 21(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199954

RESUMO

Knowing the exact nutrient composition of organic fertilizers is a prerequisite for their appropriate application to improve yield and to avoid environmental pollution by over-fertilization. Traditional standard chemical analysis is cost and time-consuming and thus it is unsuitable for a rapid analysis before manure application. As a possible alternative, a handheld X-ray fluorescence (XRF) spectrometer was tested to enable a fast, simultaneous, and on-site analysis of several elements. A set of 62 liquid pig and cattle manures as well as biogas digestates were collected, intensively homogenized and analysed for the macro plant nutrients phosphorus, potassium, magnesium, calcium, and sulphur as well as the micro nutrients manganese, iron, copper, and zinc using the standard lab procedure. The effect of four different sample preparation steps (original, dried, filtered, and dried filter residues) on XRF measurement accuracy was examined. Therefore, XRF results were correlated with values of the reference analysis. The best R2s for each element ranged from 0.64 to 0.92. Comparing the four preparation steps, XRF results for dried samples showed good correlations (0.64 and 0.86) for all elements. XRF measurements using dried filter residues showed also good correlations with R2s between 0.65 and 0.91 except for P, Mg, and Ca. In contrast, correlation analysis for liquid samples (original and filtered) resulted in lower R2s from 0.02 to 0.68, except for K (0.83 and 0.87, respectively). Based on these results, it can be concluded that handheld XRF is a promising measuring system for element analysis in manures and digestates.


Assuntos
Biocombustíveis , Esterco , Animais , Bovinos , Fertilizantes/análise , Nutrientes , Espectrometria por Raios X , Suínos
6.
Huan Jing Ke Xue ; 42(7): 3555-3564, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212682

RESUMO

The spatial distribution of fertilization intensity and its influencing factors are significant for the accurate management of fertilization and pollution prevention and control. Previous studies are mostly limited to the discussion of human factors that influences the spatial distribution of fertilization intensity while ignoring natural geographical factors. Based on the chemical fertilizer survey data collected from 23492 sites in Chengdu Plain and combined with Geostatistics analysis and Geographic Information System (GIS) technology, the spatial distribution characteristics and influencing factors of average nitrogen and phosphorus fertilizer application intensity from 2010 to 2015 in this region were explored. The results show that:① the average annual application intensity of nitrogen and phosphorus fertilizer in the study area from 2010 to 2015 is generally in the low and medium risk intensity of 120-360 kg·hm-2 and 60-180 kg·hm-2. The high risk intensity is mainly distributed in the grain (fruit) and vegetable growing areas such as Pidu, Pengzhou, Shifang, Longquanyi and Jintang, while the relatively low value areas are mostly distributed in the south and northeast. ② the nugget coefficients of nitrogen and phosphorus fertilizer application intensities are 66.17% and 41.60%. Their spatial distribution is determined by structural and random factors, showing a moderate spatial autocorrelation. ③ both human and natural factors have significant effects on the application intensity of nitrogen and phosphorus fertilizer. The crop type (fine classification) can explain the spatial variation of nitrogen fertilizer and phosphorus fertilizer respectively by 12.90% and 25.10%, which is the main controlling factor affecting the spatial distribution of nitrogen and phosphorus application intensity; the importance of soil parent material is second only to the planting crop type, and the independent explanation ability of phosphorus application intensity is about 3.6 times higher than that of nitrogen application intensity. When the type of planting crop plays a decisive role, the soil parent material still deeply restricts and affects the spatial distribution of nitrogen and phosphorus fertilizer application intensity in the study area. Therefore, the comprehensive effects of planting crop types and soil parent materials should be considered in fertilization management and environmental risk analysis, and the effects of soil parent material should also be taken into account in the application of phosphate fertilizer.


Assuntos
Fertilizantes , Fósforo , Agricultura , China , Fertilizantes/análise , Nitrogênio/análise , Fósforo/análise , Solo
7.
Ecotoxicol Environ Saf ; 220: 112401, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34118747

RESUMO

Cadmium (Cd) is a trace element causing severe toxicity symptoms in plants, besides posing hazardous fitness issue due to its buildup in the human body through food chain. Nanoparticles (NPs) are recently employed as a novel strategy to directly ameliorate the Cd stress and acted as nano-fertilizers. The intend of the current study was to explore the effects of zinc oxide nanoparticles (ZnO-NPs; 50 mg/L) on plant growth, photosynthetic activity, elemental status and antioxidant activity in Oryza sativa (rice) under Cd (0.8 mM) stress. To this end, the rice plants are treated by Cd stress at 15 days after sowing (DAS), and the treatment was given directly into the soil. Supply of ZnO-NPs as foliar spray was given for five consecutive days from 30 to 35 DAS, and sampling was done at 45 DAS. However, rice plants supplemented with ZnO-NPs under the Cd toxicity revealed significantly increased shoot length (SL; 34.0%), root fresh weight (RFW; 30.0%), shoot dry weight (SDW; 23.07%), and root dry weight (RDW; 12.24%). Moreover, the ZnO-NPs supplement has also positive effects on photosynthesis related parameters, SPAD value (40%), chloroplast structure, and qualitatively high fluorescence observed by confocal microscopy even under Cd stress. ZnO-NPs also substantially prevented the increases of hydrogen peroxide (H2O2) and malondialdehyde (MDA) triggered by Cd. Physiological and biochemical analysis showed that ZnO-NPs increased enzymatic activities of superoxide dismutase (SOD; 59%), catalase (CAT; 52%), and proline (17%) that metabolize reactive oxygen species (ROS); these increases coincided with the changes observed in the H2O2 and MDA accumulation after ZnO-NPs application. In conclusion, ZnO-NPs application to foliage has great efficiency to improve biomass, photosynthesis, protein, antioxidant enzymes activity, mineral nutrient contents and reducing Cd levels in rice. This can be attributed mainly from reduced oxidative damage resulted due to the ZnO-NPs application.


Assuntos
Antioxidantes/metabolismo , Cádmio/efeitos adversos , Nanopartículas , Oryza/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Poluentes do Solo/efeitos adversos , Óxido de Zinco/farmacologia , Biomassa , Catalase/metabolismo , Produtos Agrícolas/efeitos adversos , Produtos Agrícolas/fisiologia , Fertilizantes , Humanos , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Oryza/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta , Solo/química , Superóxido Dismutase/metabolismo , Óxido de Zinco/administração & dosagem
8.
Artigo em Inglês | MEDLINE | ID: mdl-34073443

RESUMO

Few studies have focused on the combined application of digestate and straw and its feasibility in rice production. Therefore, we conducted a two-year field experiment, including six treatments: without nutrients and straw (Control), digestate (D), digestate + fertilizer (DF), digestate + straw (DS), digestate + fertilizer + straw (DFS) and conventional fertilizer + straw (CS), to clarify the responses of rice growth and paddy soil nutrients to different straw and fertilizer combinations. Our results showed that digestate and straw combined application (i.e., treatment DFS) increased rice yield by 2.71 t ha-1 compared with the Control, and digestate combined with straw addition could distribute more nitrogen (N) to rice grains. Our results also showed that the straw decomposition rate at 0 cm depth under DS was 5% to 102% higher than that under CS. Activities of catalase, urease, sucrase and phosphatase at maturity under DS were all higher than that under both Control and CS. In addition, soil organic matter (SOM) and total nitrogen (TN) under DS and DFS were 20~26% and 11~12% higher than that under B and DF respectively, suggesting straw addition could benefit paddy soil quality. Moreover, coupling straw and digestate would contribute to decrease the N content in soil surface water. Overall, our results demonstrated that digestate and straw combined application could maintain rice production and have potential positive paddy environmental effects.


Assuntos
Oryza , Agricultura , Fertilizantes , Nitrogênio , Solo , Água
9.
Molecules ; 26(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063701

RESUMO

Agricultural production is influenced by the water content in the soil and availability of fertilizers. Thus, superabsorbent hydrogels, based on polyacrylamide, natural cashew tree gum (CG) and potassium hydrogen phosphate (PHP), as fertilizer and water releaser were developed. The structure, morphology, thermal stability and chemical composition of samples of polyacrylamide and cashew tree gum hydrogels with the presence of fertilizer (HCGP) and without fertilizer (HCG) were investigated, using X-ray diffractometry (XRD), Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA/DTG) and Energy Dispersive Spectroscopy (EDS). Swelling/reswelling tests, textural analysis, effect of pH, release of nutrients and kinetics were determined; the ecotoxicity of the hydrogels was investigated by the Artemia salina test. The results showed that PHP incorporation in the hydrogel favored the crosslinking of chains. This increased the thermal stability in HCGP but decreased the hardness and adhesion properties. The HCGP demonstrated good swelling capacity (~15,000 times) and an excellent potential for reuse after fifty-five consecutive cycles. The swelling was favored in an alkaline pH due to the ionization of hydrophilic groups. The sustained release of phosphorus in HCGP was described by the Korsmeyer-Peppas model, and Fickian diffusion is the main fertilizer release mechanism. Finally, the hydrogels do not demonstrate toxicity, and HCGP has potential for application in agriculture.


Assuntos
Resinas Acrílicas/química , Anacardium , Hidrogéis/química , Gomas Vegetais/química , Animais , Artemia , Reagentes para Ligações Cruzadas , Preparações de Ação Retardada , Difusão , Fertilizantes , Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Nutrientes , Fosfatos/química , Fósforo , Polímeros/química , Polissacarídeos/química , Potássio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Árvores , Água , Difração de Raios X
10.
Mycorrhiza ; 31(4): 483-496, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34173082

RESUMO

Arbuscular mycorrhizal fungi (AMF) are ubiquitous in agroecosystems, but their role in mediating agricultural yield remains contested. Field experiments testing effects of realistic agronomic practices of intensification on AM fungus composition and yields are scarce, especially in the low-input systems of sub-Saharan Africa. A large, full-factorial field experiment was conducted in South-Kivu (DR Congo), testing effects of fallow duration (6 vs. 12 months), genotype (landrace vs. improved), and fertilizer management (control vs. five combinations omitting N, P, K, and/or secondary macro- and micronutrients) on yields of cassava, an important staple crop strongly colonized by AMF. Furthermore, we used DNA-metabarcoding to evaluate effects of these agronomic practices on the AM fungal communities on the roots. The shorter fallow duration strongly increased diversity and richness of AMF, but this did not correspond with increased yields. Cassava yield was mainly determined by genotype, being largest for the improved genotype, which coincided with a significantly higher sum of AM fungal sequences. Effects of fertilizer or genotype on community composition were minor to absent. We found no evidence that increased AMF richness and diversity enhanced cassava yields. In contrast, the use of the improved genotype and mineral fertilizers strongly benefitted yields, without compromising richness or diversity of AMF. Cassava-AMF associations in this work appear robust to fertilizer amendments and modern genotype improvement.


Assuntos
Manihot , Micorrizas , Fertilizantes , Genótipo , Micorrizas/genética , Raízes de Plantas , Microbiologia do Solo
11.
Artigo em Inglês | MEDLINE | ID: mdl-34068614

RESUMO

Isotopocule signatures of N2O (δ15Nbulk, δ18O and site preference) are useful for discerning soil N2O source, but sometimes, N fertilizer is needed to ensure that there is enough N2O flux for accurate isotopocule measurements. However, whether fertilizer affects these measurements is unknown. This study evaluated a gradient of NH4NO3 addition on N2O productions and isotopocule values in two acidic subtropical soils. The results showed that N2O production rates obviously amplified with increasing NH4NO3 (p < 0.01), although a lower N2O production rate and an increasing extent appeared in forest soil. The δ15Nbulk of N2O produced in forest soil was progressively enriched when more NH4NO3 was added, while becoming more depleted of agricultural soil. Moreover, the N2O site preference (SP) values collectively elevated with increasing NH4NO3 in both soils, indicating that N2O contributions changed. The increased N2O production in agricultural soil was predominantly due to the added NH4NO3 via autotrophic nitrification and fungal denitrification (beyond 50%), which significantly increased with added NH4NO3, whereas soil organic nitrogen contributed most to N2O production in forest soil, probably via heterotrophic nitrification. Lacking the characteristic SP of heterotrophic nitrification, its N2O contribution change cannot be accurately identified yet. Overall, N fertilizer should be applied strictly according to the field application rate or N deposition amount when using isotopocule signatures to estimate soil N2O processes.


Assuntos
Fertilizantes , Solo , Fertilizantes/análise , Nitrificação , Nitrogênio/análise , Óxido Nitroso/análise
12.
Molecules ; 26(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34073001

RESUMO

The effects of two types of biochar on corn production in the Mediterranean climate during the growing season were analyzed. The two types of biochar were obtained from pyrolysis of Pinus pinaster. B1 was fully pyrolyzed with 55.90% organic carbon, and B2 was medium pyrolyzed with 23.50% organic carbon. B1 and B2 were supplemented in the soil of 20 plots (1 m2) at a dose of 4 kg/m2. C1 and C2 (10 plots each) served as control plots. The plots were automatically irrigated and fertilizer was not applied. The B1-supplemented plots exhibited a significant 84.58% increase in dry corn production per square meter and a 93.16% increase in corn wet weight (p << 0.001). Corn production was no different between B2-supplemented, C1, and C2 plots (p > 0.01). The weight of cobs from B1-supplemented plots was 62.3%, which was significantly higher than that of cobs from C1 and C2 plots (p < 0.01). The grain weight increased significantly by 23% in B1-supplemented plots (p < 0.01) and there were no differences between B2-supplemented, C1, and C2 plots. At the end of the treatment, the soil of the B1-supplemented plots exhibited increased levels of sulfate, nitrate, magnesium, conductivity, and saturation percentage. Based on these results, the economic sustainability of this application in agriculture was studied at a standard price of €190 per ton of biochar. Amortization of this investment can be achieved in 5.52 years according to this cost. Considering the fertilizer cost savings of 50% and the water cost savings of 25%, the amortization can be achieved in 4.15 years. If the price of biochar could be reduced through the CO2 emission market at €30 per ton of non-emitted CO2, the amortization can be achieved in 2.80 years. Biochar markedly improves corn production in the Mediterranean climate. However, the amortization time must be further reduced, and enhanced production must be guaranteed over the years with long term field trials so that the product is marketable or other high value-added crops must be identified.


Assuntos
Agricultura/métodos , Carvão Vegetal/farmacologia , Zea mays/crescimento & desenvolvimento , Dióxido de Carbono/análise , Carvão Vegetal/metabolismo , Clima , Produtos Agrícolas/efeitos dos fármacos , Grão Comestível/química , Fertilizantes , Região do Mediterrâneo , Óxido Nitroso/análise , Solo , Zea mays/química
13.
Waste Manag ; 130: 155-166, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34090239

RESUMO

Black soldier fly (BSF) larval bioconversion can recycle nutrients in organic wastes into larval biomass and frass. While the frass has been commonly marketed as a soil amendment, its usefulness in soilless cultivation remains largely unexplored. Growth experiments were conducted to investigate the effectiveness of surplus food-derived and okara-derived BSF larval frass as an incorporated compost, side-dress fertilizer and frass-tea drench for the cultivation of pak choi and lettuce in waste-wood derived biochar growing media. Pak choi yields from treatments with surplus food-derived frass and biochar at a 10:90 (v/v) ratio and inorganic fertilizer were comparable to those of the control which consisted of soil, peat-based compost and inorganic fertilizer. However, yields decreased with increasing frass incorporation rates owing to high salinity and potentially low oxygen conditions in the growing media. When used as a fertilizer on biochar-coir growing media, the direct application of frass as a side-dress fertilizer was 1.6-6.8 times more effective in promoting lettuce growth than the application as a frass-tea drench. Frass fertilizers derived from surplus food outperformed those derived from okara by 1.3-5.3 times. Lettuce yields were not significantly different between the treatment with surplus food-derived frass applied as a side-dress fertilizer and the control of liquid inorganic fertilizer. Variations in fertilizing potential were attributed to nutrient availability and the presence of plant growth promoting microbes in the growing media. BSF larval frass derived from food waste shows promise in partially replacing unsustainable agricultural inputs for leafy vegetable cultivation, including soil and inorganic fertilizers.


Assuntos
Compostagem , Dípteros , Eliminação de Resíduos , Animais , Carvão Vegetal , Fertilizantes , Larva , Solo , Chá , Verduras
14.
Nat Commun ; 12(1): 3484, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108462

RESUMO

Ecosystems across the globe receive elevated inputs of nutrients, but the consequences of this for soil fungal guilds that mediate key ecosystem functions remain unclear. We find that nitrogen and phosphorus addition to 25 grasslands distributed across four continents promotes the relative abundance of fungal pathogens, suppresses mutualists, but does not affect saprotrophs. Structural equation models suggest that responses are often indirect and primarily mediated by nutrient-induced shifts in plant communities. Nutrient addition also reduces co-occurrences within and among fungal guilds, which could have important consequences for belowground interactions. Focusing only on plots that received no nutrient addition, soil properties influence pathogen abundance globally, whereas plant community characteristics influence mutualists, and climate influence saprotrophs. We show consistent, guild-level responses that enhance our ability to predict shifts in soil function related to anthropogenic eutrophication, which can have longer-term consequences for plant communities.


Assuntos
Fertilizantes , Fungos/isolamento & purificação , Nitrogênio/farmacologia , Fósforo/farmacologia , Microbiologia do Solo , Fertilizantes/análise , Fungos/efeitos dos fármacos , Pradaria , Micorrizas/efeitos dos fármacos , Micorrizas/isolamento & purificação , Micorrizas/fisiologia , Nitrogênio/análise , Nutrientes/análise , Nutrientes/farmacologia , Fósforo/análise , Raízes de Plantas/microbiologia , Solo/química
15.
Water Sci Technol ; 83(12): 3041-3053, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34185698

RESUMO

Struvite from nutrient-rich wastewaters has been identified as a potential substitute for commercial mineral fertilisers, with the added benefit of reducing threats to global food security by prolonging phosphate rock reserves. A fertilisation test using grass (Brachiaria brizantha Marandú) and a sand column leaching test was conducted to determine the agronomic effectiveness of struvite precipitates produced from the supernatant of dewatered sewage sludge (centrate) from a municipal Wastewater Treatment Plant (WWTP). The performance of this struvite as a fertiliser was compared with biosolids and commercial fertilisers (Urea and Triple15). The results show that the concentration of heavy metals in struvite was lower than in biosolids and below the limits of Colombia and European fertiliser regulations. Struvite increased the uptake of N and P in grass, resulting in crop yields similar to other treatments tested. Struvite use as an effective slow-release fertiliser is highly dependent on the size of crystal particles, particularly in achieving low P losses, but resulted in high N loss in the sand columns tested; N loses from struvite were higher than in the commercial fertilisers due to the struvite small particle size. Therefore, struvite represents a suitable opportunity to recover and recycle nutrients from municipal sewage sludge, facilitating the effective reuse of P and N in agriculture and uptake by plants.


Assuntos
Fertilizantes , Purificação da Água , Colômbia , Fosfatos , Fósforo , Esgotos , Estruvita
16.
Sci Total Environ ; 788: 147798, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34034165

RESUMO

A link between microbial life history strategies and soil organic carbon storage in agroecosystems is presumed, but largely unexplored at the gene level. We aimed to elucidate whether and how differential organic material amendments (manure versus peat-vermiculite) affect, relative to sole chemical fertilizer application, the link between microbial life history strategies and soil organic carbon storage in a wheat-maize rotation field experiment. To achieve this goal, we combined bacterial 16S rRNA gene and fungal ITS amplicon sequencing, metagenomics and the assembly of genomes. Fertilizer treatments had a significantly greater effect on microbial community composition than aggregate size, with soil available phosphorus and potassium being the most important community-shaping factors. Limitation in labile carbon was linked to a K-selected oligotrophic life history strategy (Gemmatimonadetes, Acidobacteria) under sole chemical fertilizer application; defined by a significant enrichment of genes involved in resource acquisition, polymer hydrolysis, and competition. By contrast, excess of labile carbon promoted an r-selected copiotrophic life history strategy (Cytophagales, Bacillales, Mortierellomycota) under manure treatment; defined by a significant enrichment of genes involved in cellular growth. A distinct life history strategy was not observed under peat-vermiculite treatment, but rather a mix of both K-selected (Acidobacteria) and r-selected (Actinobacteria, Mortierellomycota) microorganisms. Compared to sole chemical fertilizer application, soil organic carbon storage efficiency was significantly increased by 26.5% and 50.0% under manure and peat-vermiculite treatments, respectively. Taken together, our results highlight the importance of organic material amendments, but in particular a one-time peat-vermiculite application, to promote soil organic carbon storage as a potential management strategy for sustainable agriculture.


Assuntos
Carbono , Solo , Agricultura , Fertilizantes/análise , Esterco , RNA Ribossômico 16S , Rotação , Microbiologia do Solo , Triticum , Zea mays
17.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1753-1760, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34042370

RESUMO

Energy saving, emission reduction, and efficiency improvement are important directions for agricultural development in Central Henan Province, the main grain production area in the Huang-huai-hai Plain. Based on the tillage and fertilization positioning experiment in 2010, we investigated the effects of three tillage methods (deep tillage, shallow tillage, and no-tillage) and two fertilization methods (nitrogen fertilizer and nitrogen fertilizer+organic fertilizer) on soil nitrogen balance and greenhouse gas emissions from 2018 to 2019. The results showed that soil nitrogen accumulation increased with organic fertilizer addition. During wheat and maize maturation, soil total nitrogen accumulation in the 0-60 cm layer was the highest under the treatment of shallow tillage+organic fertilizer, being 8058.53 and 8299 kg N·hm-2, respectively, being 3.2%-27.4% and 4.3%-7.2% higher than other treatments. The treatment with organic fertilizer addition resulted in nitrogen surplus. The shallow tillage+organic fertilizer treatment led to the highest nitrogen surplus (13.57 kg N·hm-2), which was 9.52 and 0.18 kg N·hm-2 higher than deep tillage+organic fertilizer and no tillage+organic fertilizer treatments. Nitrate leaching was the main way of nitrogen losses, accounting for 73.4%-76.9% of the total losses. The amount of nitrate leaching was the highest in deep tillage+organic fertilizer treatment (48.37 kg N·hm-2), being 18.9%-35.1% higher than other treatments. Results of greenhouse gases emission during 2018-2019 showed that global warming potential was the highest under the treatment of deep tillage+organic fertilizer, which was 33070 kg N·hm-2, being 6.6%-26.8% higher than other treatments. The treatment of organic fertilizer addition increased the emission of N2O and CO2 and reduced the absorption of CH4. The annual grain yield was highest under the treatment of deep tillage+organic fertilizer, which was 5.0%-17.1% higher than other treatments. The crop harvest index was the highest under the treatment of shallow tillage+organic fertilizer. The recommended cropping mode in Central Henan Pro-vince is shallow tillage+organic fertilizer, which could ensure crop yields, maintain soil nitrogen balance, and reduce greenhouse gas emissions.


Assuntos
Gases de Efeito Estufa , Agricultura , China , Fertilidade , Fertilizantes/análise , Gases de Efeito Estufa/análise , Nitrogênio/análise , Óxido Nitroso/análise , Rotação , Solo , Triticum , Zea mays
18.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1791-1798, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34042375

RESUMO

Clarifying the pattern of nitrogen absorption and utilization of rice under the treatments of Astragalus sinicus combined with chemical fertilizer application and the pattern of absorption, utilization, distribution and residue of A. sinicus nitrogen in rice-soil system could provide basis to rational fertilization for rice planting area in southern Henan. In this study, undisturbed soil column simulation and isotope tracer technology of 15N were used to examine the differences of nitrogen uptake and utilization of rice, nitrogen nutrient balance of rice-soil system and nitrogen uptake, utilization, distribution and residue of A. sinicus nitrogen after mineralization and decomposition among seven treatments. The treatments involved 1) no fertilization (CK); 2) chemical fertilizer+22500 kg·hm-2 A. sinicus (FM1); 3) chemical fertilizer+30000 kg·hm-2 A. sinicus (FM2); 4) chemical fertilizer+37500 kg·hm-2 A. sinicus (FM3); 5) chemical fertilizer+22500 kg·hm-2 A. sinicus +lime (FM1+CaO); 6) chemical fertilizer+30000 kg·hm-2 A. sinicus lime (FM2+CaO); 7) chemical fertilizer+37500 kg·hm-2 A. sinicus +lime (FM3+CaO). Results showed that compared with CK, fertilization significantly increased nitrogen uptake of grain and rice stalks, apparent nitrogen loss, and nitrogen surplus. The grain nitrogen uptake, rice straw nitrogen uptake and nitrogen use efficiency of rice increased firstly and then decreased with the increasing A. sinicus application rates, while the apparent nitrogen loss and nitrogen surplus showed the opposite trend. The best performance was presented under the treatment of chemical fertilizer combined with 30000 kg·hm-2 of A. sinicus. Lime addition could increase grain nitrogen uptake, rice straw nitrogen uptake, and nitrogen use efficiency of rice, while reducing apparent nitrogen loss and nitrogen surplus, with the best performance of FM2+CaO. For all the treatments, the proportion of nitrogen absorbed by rice from A. sinicus was 6.3%-13.2%, while that from soil and chemical fertilizer was 86.8%-93.7%. The utilization ratio of A. sinicus nitrogen by rice was 23.8%-33.6%. The utilization ratio of A. sinicus nitrogen in different parts of rice was grain > stem and leaf > root. The residue rate of A. sinicus nitrogen in soil was 37.6%-62.4%. The loss rate of A. sinicus nitrogen was 7.8%-38.6%. Comprehensively considering nitrogen absorption and utilization of rice, nitrogen nutrient balance of rice-soil system, and the distribution situation of nitrogen from A. sinicus in rice, FM2+CaO was the optimum fertilization pattern in the study area.


Assuntos
Fertilizantes , Oryza , Agricultura , Fertilizantes/análise , Nitrogênio/análise , Solo
19.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1807-1815, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34042377

RESUMO

To get an optimal mode of irrigation and nitrogen supply for table grape production in North China, a pot experiment was conducted to investigate the effects of different irrigation modes and N application rates on dry matter accumulation and distribution, yield, water use efficiency, and nitrogen use efficiency of table grape. The irrigation modes included conventional drip irrigation (CDI, with sufficient irrigation), alternate partial root-zone drip irrigation (ADI, with 50% amount of the irrigation water of CDI) and fixed partial root-zone drip irrigation (FDI, with 50% amount of the irrigation water of CDI). The nitrogen application rates were set at 0.4 (N1), 0.8 (N2) and 1.2 (N3) g·kg-1 dry soil. The results showed that compared with CDI, ADI and FDI reduced new shoot pruning amount by 34.8% and 11.2%, respectively. New shoot pruning amount increased with increasing N application rates, being highest under CDIN3. Dry matter accumulation of ADI was the highest, being 5.1% and 12.8% higher than CDI and FDI. Dry matter accumulation was higher under N2 and N3 than N1. Compared with CDI and FDI, leaf to fruit ratio reduced but harvest index significantly increased in ADI, while those variables showed no significant difference among diffe-rent N application rates. The ratio of pruning amount to the biomass accumulated in the current year in ADIN2 was the lowest among the treatments. Compared with CDI and FDI, ADI increased grape fruit yield by 6.0% and 10.4%, respectively. Fruit yield was enhanced with increasing nitrogen application rates under the same irrigation condition, with the highest yield under the ADIN2 and ADIN3. Water use efficiency (WUE) increased significantly in ADI compared with CDI and FDI, with the highest value being observed in ADI coupled with N2 or N3. Nitrogen use efficiency (NUE) showed a trend of ADI>CDI>FDI. In addition, NUE decreased with increasing nitrogen supply level across the irrigation modes. In conclusion, ADIN2 could reduce the redundant growth of grape tree, promote the transfer of dry matter to fruit, which increased yield and use efficiency of both water and nitrogen, which is a suitable coupling water and nitrogen supply mode for grape production in northern China.


Assuntos
Nitrogênio , Vitis , Irrigação Agrícola , Biomassa , China , Fertilizantes , Solo , Água/análise
20.
Food Chem ; 359: 129961, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33945985

RESUMO

The effects of different fertilisation treatments with arbuscular mycorrhizal fungi (AMF) inoculation on AMF root colonisation, fruit yield, nutrient and total phenol contents, volatile compound composition, and sensory attributes of tomato (Solanum lycopersicum L.) were investigated. Mineral, organic, and mineral + organic fertiliser application positively affected tomato yield (35%-50%) and phosphorus concentration (24%-29%) compared with controls. AMF application had a significant impact on the total nitrogen (+9%), manganese (+12%), and hydrophilic phenol (+8%) contents in the fruit. Volatile compounds were affected by the interactive effects of fertilisation and AMF application. The response of tomato fruit sensory quality indicators was relatively modest, with only a few sensory characteristics affected to a lesser extent. Although tomato showed susceptibility to field-native AMF, particular combinations of fertilisation and AMF inoculation were more effective at improving the quality parameters of tomatoes under field conditions applied in this study.


Assuntos
Fertilizantes , Lycopersicon esculentum/metabolismo , Micorrizas/fisiologia , Lycopersicon esculentum/microbiologia
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