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1.
ISME Commun ; 3(1): 81, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596350

RESUMO

Soil microbiomes play important roles in supporting agricultural ecosystems. However, it is still not well-known how soil microbiomes and their functionality respond to fertilization in various cropping systems. Here we examined the effects of 36 years of phosphorus, nitrogen, and manure application on soil bacterial communities, functionality and crop productivity in three contrasting cropping systems (i.e., continuous leguminous alfalfa (AC), continuous winter wheat (WC), and grain-legume rotation of winter wheat + millet - pea - winter wheat (GLR)) in a highland region of China's Loess Plateau. We showed that long-term fertilization significantly affected soil bacterial communities and that the effects varied with cropping system. Compared with the unfertilized control, fertilization increased soil bacterial richness and diversity in the leguminous AC system, whereas it decreased those in the GLR system. Fertilization, particularly manure application, enlarged the differences in soil bacterial communities among cropping systems. Soil bacterial communities were mostly affected by the soil organic carbon and nitrogen contents in the WC and GLR systems, but by the soil available phosphorous content in the AC system. Crop productivity was closely associated with the abundance of fertilization-responsive taxa in the three cropping systems. Our study highlights that legume and non-legume cropping systems should be disentangled when assessing the responses of soil microbial communities to long-term fertilizer application.

2.
Artigo em Inglês | MEDLINE | ID: mdl-36498430

RESUMO

Deficiencies of micronutrients in calcareous soils have been reported in different areas of China's Loess Plateau. The objective of this research was to study the influence of the continuous application of micronutrient fertilizers on soil properties and micronutrient availability in this region. The micronutrient fertilizer field plot experiment began in 1984. It included Zn, Mn and Cu fertilizer treatments and the control treatment. The crop system was continuously cropped winter wheat. The soil properties and available Zn, Mn, Cu and Fe were measured. Their relationships were analyzed through correlation and path analysis. After 31 years, the soil pH, CaCO3 and available P levels decreased; in contrast, the organic matter, fulvic acid, reducing substances and soil moisture levels in the surface soil increased in the micronutrient fertilized treatments compared to the control treatment. Cu and Zn fertilizers promoted the available Cu and Zn levels in the surface and deep soil, but available Mn was not significantly affected by Mn fertilizer. It can be seen from the interaction between the micronutrient availability and micronutrient fertilizers that Zn, Cu and Mn fertilizers can increase the available Fe level; Mn fertilizer can increase the available Cu level, and Cu and Mn fertilizers can increase the available Zn level. This means that Fe, Cu and Zn availability were easy to implement, whereas the soil-available Mn was difficult to improve in calcareous soils on the Loess Plateau. Fulvic acid and organic matter showed a significant and direct effect on the available Zn; the available Mn and Fe were mainly affected by the soil CaCO3 and moisture; the available Cu was mainly affected by the soil organic matter, available P and reducing substances. These results indicate the importance of organic matter in calcareous soils; it can not only directly affect the availability of micronutrients but also indirectly affect their availability through the indirect interaction with fulvic acid, reducing substances, available P and CaCO3. The above conclusions suggest that the long-term micronutrient fertilizers changed some important soil properties and increased the micronutrient availability in the loess-derived soil.


Assuntos
Poluentes do Solo , Oligoelementos , Fertilizantes/análise , Solo/química , Micronutrientes/análise , Oligoelementos/análise , Poluentes do Solo/análise
3.
Ecotoxicol Environ Saf ; 214: 111994, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33711576

RESUMO

This study investigated the vermicomposting of spent drilling fluid (SDF) from the nature-gas industry mixed with cow dung in 0% (T1), 20% (T2), 30% (T3), 40% (T4), 50% (T5), and 60% (T6) ratio employing Eisenia fetida under a 6 weeks trial. Eisenia. fetida showed better growth and reproduction performances in the first three vermireactors (T1-T3), and the mortality was higher in the vermireactors that contained more spent drilling fluid (≥40%). Vermicomposting results in a decrease in total organic carbon, C/N ratio, and an increase in EC, total nitrogen, total phosphorous, total potassium compared to their initial values. The RadViz and VizRank showed that vermicomposting results in a greater impact on the C/N ratio (15.24-35.48%) and EC (7.29-26.45%) compared to other parameters. Activities of urease and alkaline phosphatase during vermicomposting initially increased and then declined suggesting vermicompost maturity. Also, seed germination, mitotic index and chromosomal abnormality assays using cowpea signified that the vermicomposts T2 is suitable for agricultural use due to the lower phytotoxicity and cytotoxicity. The results indicated that SDF could be converted into good quality manure by vermicomposting if mixed up to 20% with cow dung.


Assuntos
Compostagem/métodos , Oligoquetos , Animais , Biodegradação Ambiental , Bovinos , Estudos de Viabilidade , Fezes , Feminino , Esterco , Nitrogênio , Fósforo , Reprodução , Solo
4.
Sci Total Environ ; 766: 142663, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33153750

RESUMO

Due to the high cropping index and substantial agricultural inputs in greenhouse cultivation systems (GCS) compared to traditional farming methods, the environmental problems caused by heavy metals in GCS are becoming increasingly serious. The concentration of the heavy metals As, Cd, Cr, Cu, Pb and Zn in soil and food crops were analyzed and assessed in two study areas. There were greater accumulation of heavy metals in soils from Central Shaanxi (CS) than that from Northern Shaanxi (NS). However, heavy metal concentrations in leafy vegetables were higher in NS compared to CS, particularly Cr accumulation in leafy vegetables. Overall, leafy vegetables contained higher concentrations of heavy metals than fresh fruits and fruit vegetables from both areas. The heavy metal transfer factors (TF) for fresh fruits and fruit vegetables were as follows: Cu > Zn > Cd > Cr > As > Pb. However, in leafy vegetables, Cd had a higher TF value than the other metals tested. The target hazard quotient (THQ) values were less than 1 for fruits and vegetables, except for As in leafy vegetables from NS. The THQ values indicated that As contamination was the most serious concern, followed by Cu > Zn > Cd > Pb > Cr in both areas. The soil threshold value (STV) based on THQ showed that the level of As in leafy vegetables grown in alkaline soil was 10.85, which was inferior to the current standards. This study demonstrates the health risks associated with the heavy metal content of fruits and vegetables grown in GCS and suggests that necessary measures should be taken to reduce the accumulation of heavy metals in GCS crops in northwest China.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Contaminação de Alimentos/análise , Frutas/química , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise , Verduras
5.
Sci Rep ; 10(1): 19497, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177641

RESUMO

Water infiltration into the soil profile are related to the condition of the soil texture, soil bulk density, and water intensity, it is also affected by the physicochemical properties of the water. In this study, we tested the effect of two different chemical properties of water (groundwater for irrigation and naturally accumulated water) on water infiltration in seven different mixed soil consisting of different ratios of feldspathic sandstone and aeolian sandy soil (1:0, 5:1, 2:1, 1:1, 1:2, 1:5, 0:1) through laboratory soil column testing. Our results show that when the textures of the mixed soils are silty loam and sandy loam (ratios of feldspathic sandstone to aeolian sandy soil 1:0, 5:1, 2:1, 1:1 and 1:2), the infiltration time of the naturally accumulated water is significantly longer than the infiltration time of the groundwater for irrigation. When the mixed soil texture is loamy sand and sand (the ratio of feldspathic sandstone to sandy soil is 1:5 and 0:1), there was no significant difference in the infiltration time of the naturally accumulated water and of the groundwater for irrigation. Using water with the same chemical properties, the infiltration time in different ratios of mixed soil decreases from 1:0, 5:1, 2:1, 1:1, 1:2, 1:5, to 0:1. Using the same feldspathic sandstone to aeolian sandy soil ratio, the cumulative infiltration using naturally accumulated water is greater than that using groundwater for irrigation, and the difference in cumulative infiltration is greatest when the ratio of feldspathic sandstone to sandy soil is 2:1. The relationship between the cumulative infiltration and elapsed time is consistent with the Logarithmic model. The changes in wetting front migration distance are consistent with the changes in the cumulative infiltration. The infiltration characteristics of water in the mixed soil are affected by a combination of water chemical property and soil texture.

6.
Sci Total Environ ; 577: 267-278, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27829504

RESUMO

Although many studies have been conducted on crop yield in rain-fed agriculture, the possible impacts of climate change on the carbon (C) dynamics of rain-fed rotation systems, particularly their direction and magnitude at the long-term scale, are still poorly understood. In this study, the sensitivity of C dynamics of a typical rotation system to elevated CO2 and changed temperature and precipitation were first tested using the CENTURY model, based on data collected from a 30-year field experiment of a corn-wheat-wheat-millet (CWWM) rotation system in the tableland of the Loess Plateau. The possible responses of crop biomass C and soil organic C (SOC) accumulation were then evaluated under scenarios representing the Representative Concentration Pathways (RCPs) 4.5 and 8.5. The results indicated that elevated CO2 and increased precipitation exerted positive effect on biomass C in CWWM rotation system, while increasing the temperature by 1°C, 2°C and 4°C had negative effects on biomass C due to opposite responses of corn and winter wheat to warming. SOC accumulation was enhanced by increased CO2 concentration and precipitation but impaired by increased temperature. Under future RCP scenarios with dynamic CO2, the biomass C of corn exhibited decrease during the period of 2046-2075 under RCP4.5 and the period of 2016-2075 under RCP8.5 due to reduced precipitation and a warmer climate. In contrast, winter wheat would benefit from increased CO2 and temperature and was projected to have larger biomass C under both RCP scenarios. Although the climate condition had large differences between RCP4.5 and RCP8.5, the projected SOC had similar trends under two scenarios due to CO2 fertilizer effect and precipitation fluctuation. These results implied that crop biomass C and SOC accumulation in a warmer environment are strongly related to precipitation, and increase in field water storage should be emphasized in coping with future climate.

7.
Ying Yong Sheng Tai Xue Bao ; 27(1): 91-8, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-27228597

RESUMO

This study was conducted to analyze the responses of soil organic carbon (SOC) and total nitrogen (TN) to three typical re-vegetation patterns, i.e., grassland, alfalfa land and peashrub land on the Loess Plateau of China, and also to assess the dynamics of SOC and TN with re-vegetation age. The results showed that all the three re-vegetation practices increased the concentrations of SOC and TN in the 0-10 cm soil layer, but their effects differed with re-vegetation age. Compared with adjacent croplands, the concentrations of SOC and TN in the 0-10 cm soil layer in grassland did not change within 10 years of succession, but increased after 20 years of succession. In alfalfa land, the concentrations of SOC and TN increased by 51.6%-82.9% and 43.4%-67.0% in the 0-10 cm soil layer, with the increasing rates of stocks of SOC and TN being 0.17-0.46 and 0.015-0.043 t · hm⁻² · a⁻¹, respectively. However, SOC and TN were not affected by re-vegetation age in alfalfa land. The increases of concentrations of SOC and TN remained high in the first 20 years after conversion of cropland to peashrub land, but decreased after 40 years of conversion. In conclusion, the conversion of croplands to peashrub or alfalfa land could be better in contributing to high stocks of SOC and TN than natural succession of grassland. However, their positive effects on the enrichment of SOC and TN may not be sustainable due to the scarcity of soil moisture and high water consumption of these two re-vegetation plants.


Assuntos
Carbono/análise , Recuperação e Remediação Ambiental , Nitrogênio/análise , Plantas , Solo/química , China , Água , Vento
8.
PLoS One ; 10(12): e0145370, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26694965

RESUMO

The bioavailability and fractionation of Cu reflect its deliverability in soil. Little research has investigated Cu supply to crops in soil under long-term rotation and fertilisation on the Loess Plateau. A field experiment was conducted in randomized complete block design to determine the bioavailability and distribution of Cu fractions in a Heilu soil (Calcaric Regosol) after 18 years of rotation and fertilisation. The experiment started in 1984, including five cropping systems (fallow control, alfalfa cropping, maize cropping, winter wheat cropping, and grain-legume rotation of pea/winter wheat/winter wheat + millet) and five fertiliser treatments (unfertilised control, N, P, N + P, and N + P + manure). Soil samples were collected in 2002 for chemical analysis. Available Cu was assessed by diethylene triamine pentaacetic acid (DTPA) extraction, and Cu was fractionated by sequential extraction. Results showed that DTPA-Cu was lower in cropping systems compared with fallow control. Application of fertilisers resulted in no remarkable changes in DTPA-Cu compared with unfertilised control. Correlation and path analyses revealed that soil pH and CaCO3 directly affected Cu bioavailability, whereas available P indirectly affected Cu bioavailability. The concentrations of Cu fractions (carbonate and Fe/Al oxides) in the plough layer were lower in cropping systems, while the values in the plough sole were higher under grain-legume rotation relative to fallow control. Manure with NP fertiliser increased Cu fractions bound to organic matter and minerals in the plough layer, and its effects in the plough sole varied with cropping systems. The direct sources (organic-matter-bound fraction and carbonate-bound fraction) of available Cu contributed much to Cu bioavailability. The mineral-bound fraction of Cu acted as an indicator of Cu supply potential in the soil.


Assuntos
Agricultura/métodos , Cobre/análise , Produtos Agrícolas/crescimento & desenvolvimento , Solo/química , Disponibilidade Biológica , Quelantes/química , China , Cobre/química , Fertilização , Fertilizantes/análise , Ácido Pentético/química
9.
Ying Yong Sheng Tai Xue Bao ; 25(11): 3191-6, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25898616

RESUMO

Based on a long-term rotation and fertilization experiment in Changwu, Shaanxi, China, we determined the enzymatic activities and nutrients in soils after 27 years continuous cropping of alfalfa and wheat, respectively. The activities of invertase, urease and phosphatase were not affected by fertilization treatment within each cropping system, but they were significantly higher in the alfalfa continuous cropping system than in the wheat continuous cropping system under each fertilization treatment. The activity of hydrogen peroxidase was not affected by the type of cropping system or fertilization treatment. Across the cropping systems, the activities of soil urease, phosphatase and hydrogen peroxidase were higher while soil invertase activity was lower in N, P and manure (NPM) combined treatment compared with the other fertilization treatments. The accumulations of soil organic matter, total nitrogen and available nitrogen were greater in the alfalfa cropping system than in the wheat continuous cropping system, and the NPM treatment could improve the soil fertility.


Assuntos
Agricultura/métodos , Medicago sativa/crescimento & desenvolvimento , Solo/química , Triticum/crescimento & desenvolvimento , China , Fertilizantes , Esterco , Nitrogênio/química , Peroxidases/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Fósforo/química , Urease/metabolismo , beta-Frutofuranosidase/metabolismo
10.
Ying Yong Sheng Tai Xue Bao ; 24(5): 1354-60, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-24015555

RESUMO

A long-term experiment was conducted on the dryland of Loess Plateau to study the effects of three typical rotation systems, including wheat-sainfoin rotation, wheat-pea rotation, and wheat-maize rotation, on the nutritional quality of wheat grain protein. Rotation system and the cropping years of rotated plants affected the nutritional quality of wheat grain protein in varying degrees. As compared with continuous wheat cropping, wheat-sainfoin rotation made the nutritional quality of wheat grain protein relatively stable, and the essential amino acid content, amino acid score, amino acid ratio coefficient, chemical score, and amino acid index of the protein all relatively high, being able to be adopted as a cropping system to product high quality protein wheat in Loess Plateau. Under wheat-pea rotation, the nutritional quality of wheat grain protein after 1-year pea cropping was relatively high, but the essential amino acid content of wheat grain protein after 2-year pea cropping was relatively low, and several essential amino acid scores and chemical score of the grain protein were lower than those under continuous wheat cropping. Furthermore, the essential amino acid index was 12.2% lower than that under continuous wheat cropping. Therefore, wheat-pea rotation showed a relatively low nutritional quality of wheat grain protein. Under wheat-maize rotation, the nutritional quality of wheat grain protein was also relatively stable, but the crude protein and essential amino acid contents and amino acid balance level were lower than those under continuous wheat cropping.


Assuntos
Agricultura/métodos , Proteínas de Plantas/análise , Triticum/crescimento & desenvolvimento , Altitude , China , Grão Comestível/química , Valor Nutritivo , Fatores de Tempo
11.
Ying Yong Sheng Tai Xue Bao ; 22(3): 755-62, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21657035

RESUMO

Based on the analysis of the coercing and dynamic evolution relationships between agro-economic system and agro-ecological system, and by using modified entropy method, the weight of each evaluation index for the agro-ecolomic system in Changwu County of Shaanxi Province was determined, and, by employing coupling degree model, the coupling processes of agro-ecolomic system in the gullyarea of Loess Plateau were investigated. From 1949 to 2008, the agro-ecolomic system in the County experienced three stages of "traditional extensive agriculture", "agricultural mechanization", and "agricultural pre-modernization". In corresponding to the implement of national macro policies, the coupling degree of the agro-ecolomic system reached two peaks standing for utmost increasing phase and three valleys standing for coordinate development phase. Periods 1955-1961 and 1984-1992 were the utmost increasing phases of the coupling degree; periods 1962-1965 and 1981-1983 were the rapid transition periods responding to the national-wide policies controlling; while periods 1949-1954 and 1966-1980 were the low-level coordinated development phases. Since 1993, the system had been in the harmonious phase by a spiral development. At present, the system had a potential risk of changing from the harmonious phase to the utmost development phase. Appropriate agricultural policies and better external environment could promote the stable development of the agro-ecolomic system on a harmonious level; otherwise, a retrogressive system might be expected.


Assuntos
Agricultura/economia , Conservação dos Recursos Naturais/economia , Ecologia/economia , Ecossistema , Altitude , China , Entropia , Modelos Teóricos
12.
Ying Yong Sheng Tai Xue Bao ; 21(2): 279-86, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20461994

RESUMO

Taking a nine-year-old Fuji apple orchard in Loess Plateau as test object, this paper studied the effects of different patterns surface mulching (clean tillage, grass cover, plastic film mulch, straw mulch, and gravel mulch) on the soil properties and fruit trees growth and yield in this orchard. Grass cover induced the lowest differentiation of soil moisture profile, while gravel mulch induced the highest one. In treatment gravel mulch, the soil moisture content in apple trees root zone was the highest, which meant that there was more water available to apple trees. Surface mulching had significant effects on soil temperature, and generally resulted in a decrease in the maximum soil temperature. The exception was treatment plastic film mulch, in which, the soil temperature in summer exceeded the maximum allowable temperature for continuous root growth and physiological function. With the exception of treatment plastic film mulch, surface mulching increased the soil CO2 flux, which was the highest in treatment grass cover. Surface mulching also affected the proportion of various branch types and fruit yield. The proportion of medium-sized branches and fruit yield were the highest in treatment gravel mulch, while the fruit yield was the lowest in treatment grass cover. Factor analysis indicated that among the test surface mulching patterns, gravel mulch was most suitable for the apple orchards in gully region of Loess Plateau.


Assuntos
Agricultura/métodos , Biomassa , Malus/crescimento & desenvolvimento , Solo/análise , Altitude , China , Malus/fisiologia
13.
Huan Jing Ke Xue ; 31(12): 2995-3003, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21360891

RESUMO

By the soil respiration system, the characteristics of soil respiration were investigated to explore the correlations between soil respiration and soil temperature, soil water and soil nutrient under different land use patterns in the water-wind erosion crisscross region of the Loess Plateau. The results indicated that the seasonal changing characteristics of soil respiration were distinguished significantly among different vegetations, and soil water content and temperature were the main influencing factors. Soil respiration seasonal changing ranges, such as bare land, crop land, Medicago sativa land, Caragana korshinskii land, abandoned wild grass land, Stipa bungeana land, wild grass land, degraded Medicago sativa land, sloping Medicago sativa land, sloping abandoned wild grass land, sloping crop land and terraced crop land, were 0.32-0.82, 0.41-2.83, 0.74-2.81, 0.76-3.07, 0.67-2.79, 0.51-2.12, 0.56-2.05, 0.59-1.66, 0.42-2.09, 0.31-1.86, 0.32-1.93 and 0.41-3.17 micromol x (m2 x s)(-1). Comparing seasonal changing magnitudes of soil respiration, crop land was the biggest (167% - 203%), abandoned wild grass land (117% -154%), Caragana korshinskii land (134%), Stipa bungeana land (129%), Medicago sativa land (119%-120%) and bare land (94%) followed crop land. The smallest was degraded Medicago sativa land (92%). Bare land and degraded Medicago sativa land had small seasonal variation during the study period. Monthly average values of soil carbon flux (soil respiration) of Medicago sativa land and Caragana korshinskii land were maximal, but the maximum values under crop land were observed in July and August. Besides Q10 of crop land was also maximal, which reached 1.86. There were significant correlations between soil respiration and soil organic matter and available K. Moreover, soil respiration was affected by soil organic matter and total nitrogen in July and August when the water and heat condition were plentiful, but soil ammonium nitrogen had negative impact on soil respiration in the seasons when water and heat were not optimal.


Assuntos
Dióxido de Carbono/análise , Ecossistema , Monitoramento Ambiental/métodos , Compostos de Amônio Quaternário/análise , Solo/análise , Altitude , Caragana/crescimento & desenvolvimento , China , Conservação dos Recursos Naturais/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Medicago sativa/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Estações do Ano , Água/análise , Vento
14.
J Colloid Interface Sci ; 321(2): 332-41, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18329661

RESUMO

The enhancement effect of polycarboxylic acids on reductive dechlorination transformation of pentachlorophenol (PCP) reacting with iron oxides was studied in anoxic suspension. Batch experiments were performed with three species of iron oxides (goethite, lepidocrocite and hematite) and four species of polycarboxylic acids (oxalate, citrate, succinate, and tartrate) through anoxic abiotic reactors. The chemical analyses and morphological observation from scanning and transmission electron microscopy showed that different combinations between polycarboxylic acids and iron oxides produced distinct contents of Fe(II)-polycarboxylic ligand complexes, which significantly enhanced PCP transformation. Generation of the surface-bound Fe(II) depended on concentration of polycarboxylic acids. The optimal concentration for the enhancement was 2.0 mM oxalic acid. The dechlorination mechanism was further demonstrated by generation of chloride ions. The results suggest that surface-bound Fe(II) formed on the iron oxides surface appears to be a key factor in enhancing PCP transformation, and the mole ratio of oxalate to surface-bound Fe(II) (oxalate/Fe(II)) acted as an indicator of the enhancement effect. The enhancement mechanism attributes to strong nucleophilic ability and low reductive potential of the equivalent Fe(II)-polycarboxylate complexes. Therefore, the enhancement effects might be helpful for understanding the natural attenuation of reducible organic pollutants at the interface of contaminated soil in anoxic condition.


Assuntos
Ácidos Carboxílicos/química , Compostos Férricos/química , Pentaclorofenol/química , Poluentes Ambientais/química , Compostos de Ferro/química , Microscopia Eletrônica de Varredura , Minerais , Oxirredução , Pirimetamina , Água
15.
Ying Yong Sheng Tai Xue Bao ; 15(7): 1213-6, 2004 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-15506101

RESUMO

The study of apple orchard soil on the Weibei dryland showed that high input and high yield not only resulted in soil desiccation, but also induced nitrate accumulation in the soil profile. Generally, the soil layers with accumulated nitrate located in 40 - 260 cm depths, and the maximum nitrate content was 403.4 mg x kg(-1). Owing to the continuous application of nitrogen fertilizer, the accumulated nitrate could hardly be reused in the future, which might lead to environmental pollution. Because the soil storage water could not adjust the water utilization of apple trees, the yield of orchard was affected by precipitation. Therefore, the nitrogen application rate should be reduced, and actions should be taken to improve soil moisture in apple orchard.


Assuntos
Fertilizantes/efeitos adversos , Malus/crescimento & desenvolvimento , Nitratos/análise , Solo/análise , Água/análise , China
16.
Ying Yong Sheng Tai Xue Bao ; 14(8): 1265-8, 2003 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-14655355

RESUMO

The NO3(-)-N accumulation and distribution in soil profile of Loess Plateau dry highland were studied by long-term field trials. The results showed that NO3(-)-N was accumulated in the soil profile under N-fertilization. Application of P-fertilizer or organic manure reduced the NO3(-)-N content and its leaching depth in the soil profile. The deepest depth of NO3(-)-N accumulation was 120-200 cm under N treatment, and the peak of the accumulation was the highest in NPM treatment, with the depth of 60-120 cm. The NO3(-)-N accumulation depth was 80-140 cm for NP. Without nitrogen application, there was no evident accumulation of NO3(-)-N in soil profile. The more nitrogen used, the more NO3(-)-N accumulated in soil profile. Under the same nitrogen application rate, NO3(-)-N accumulation might decrease with increasing P application.


Assuntos
Fertilizantes , Nitratos/análise , Nitrogênio/análise , Solo/análise
17.
Ying Yong Sheng Tai Xue Bao ; 14(1): 75-8, 2003 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-12722443

RESUMO

On the basis of long-term fertilization experiments in gully area of Loess Plateau, the relationships among fertilizations, NO3(-)-N accumulation, and moisture distribution in soil profiles were evaluated. The results showed that fertilization and rainfall significantly influenced the yields. NO3(-)-was accumulated in soil profiles under N and P fertilizers and organic manure(NPM) and N and P fertilizer (NP) treatment. The accumulated NO3-N reached 340 kg.hm-2 in 60-120 cm under NPM treatment, and 220 kg.hm-2 in 80-140 cm under NP treatment, respectively. Soil moisture in 100-300 cm was significantly reduced under NPM treatment. Under NP treatment, it was significantly reduced in dry year and normal year, while under organic manure(M) treatment, it was significantly reduced in dry year. Soil moisture under P and CK treatments was relatively stable in different years. N uptake under NPM and NP treatments was significantly decreased in dry year. It reflected the close relationship among soil moisture, crops, and fertilization.


Assuntos
Fertilizantes , Nitratos/metabolismo , Nitrogênio/metabolismo , Solo/análise , Água/análise , Biomassa , China , Produtos Agrícolas/crescimento & desenvolvimento , Esterco , Compostos de Nitrogênio/metabolismo , Chuva , Fatores de Tempo
18.
Ying Yong Sheng Tai Xue Bao ; 14(11): 1893-6, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-14997640

RESUMO

The effect of long-term fertilization on the yield of winter wheat was studied on the basis of 18-year located experiment on the Loess Plateau. The results showed that the winter wheat yield increased 418.1 kg.hm-2 under N fertilization, and the average increasing rate was different with precipitation. In average and rain rich year, the average increasing rate were 30.3% and 58.9%, respectively, but in drought year, the yield decreased, and its average decreasing rate was 13.9%. The winter wheat yield under P fertilizer increased in drought year, and decreased in average and rain rich year. The average increasing rate was 6.5% in drought year, and the average decreasing rate was 15.4% and 10.0%, respectively. The average increasing rate in M, NP, PM, NM and NPM was 82.8%, 127.8%, 18.9%, 144.4%, and 169.3%, respectively. In addition, precipitation affected the amount of spike, grains per spike, and weight of thousand-grains.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes , Triticum/crescimento & desenvolvimento , Nitrogênio/farmacologia , Fósforo/farmacologia , Chuva
19.
Ying Yong Sheng Tai Xue Bao ; 14(11): 1901-5, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-14997642

RESUMO

The relationships between nitrogen and yield and between water and yield, and the fate of nitrogen under plastic film mulching for spring maize were studied with field plots and microplots in the southern Loess Plateau. The results showed that plastic-film mulching (N120C) could increase maize yield by 46.7%, comparing with no-mulching(N120UC) in same rate of fertilizer. The maize yield potentiality of mulching might be played fully, comparing with CK (no nitrogen), treatments N120 (urea nitrogen 120 kg.hm-2), N180 (urea nitrogen 180 kg.hm-2) and N120 M (urea nitrogen 120 kg.hm-2 + organic manure nitrogen 60 kg.hm-2) could raise grain yield by 41.8%, 43.9% and 34.7%, respectively. Mulching planting raised water use efficiency (WUE) by 57.9%, and raised rainfall use efficiency (RUE) by 54.5%. N120, N180 and N120M improved WUE by 38.4%, 47.4% and 32.4%, respectively, and improved RUE by 42.3%, 43.9% and 34.7%, respectively. Because the organic manure applied was not fully rotted cattle dung, which supplied available nitrogen slowly than urea, it raised yield and WUE to a low extent. Meanwhile, the experiment showed that 73.0%-83.7% of water used by maize from rainfall, which indicated that the key water to determine maize yield was rainfall in spring maize growth period. Mulching planting for maize had little impact on the fate of nitrogen fertilizer. The total recovery of nitrogen had little difference, NUE decreased 7.3%, and residual N in soil raised 6.4%, comparing with N120UC. A great part of the residual N was in 0-20 cm of soil, and no risk occurred for nitrogen leaching and accumulation to deeper soil layers in the first growth season.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes , Nitrogênio/metabolismo , Água/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
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