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Shanmin Shen - One of the best experts on this subject based on the ideXlab platform.
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effects of fertilization on Nutrient Budget and nitrogen use efficiency of farmland soil under different precipitations in northeastern china
Nutrient Cycling in Agroecosystems, 2010Co-Authors: Shanmin Shen, Hua Zhou, Zishao JiangAbstract:Based on a consecutive 16-year field trial and meteorological data, the effects of fertilization on the Nutrient Budget and nitrogen use efficiency in farmland soil under different precipitation years were studied. With no fertilization treatment, the grain yield of maize was 3,520 kg ha−1 (mean yield over 13 years). But the maximum yield increased to 7,470 kg ha−1 when treated with mineral N, P and K fertilizers and recycled manure. The Nutrient uptake also increased by twofold to threefold in NPKM treated field compared with that in the control treatment. The highest yields were obtained in years with normal precipitation, despite the different fertilization schemes. The lowest yields were obtained in drought or waterlogging years, which were 44.7–58.5% of the yields in years with normal precipitation. It also appeared that the deficits of N, P and K were greater in the years with proper precipitation than those in arid or flood years, because more production was removed from the field. Soil total N decreased significantly when treated with mineral fertilizer or recycled manure alone. The maximum deficit of soil total N was observed in control treatment (557 kg ha−1) from 1990 to 2005. The N treatment resulted in a significant negative balance of P, due to the high yield of the crop in response to applied N. The application of NP or N to soils resulted in a greater negative K balance than that of the control. The greatest negative balance of total P and available P were obtained under the control and N treatment, and the highest deficit of soil total K and exchangeable K were obtained under NP treatment. We found that the rate of 150 kg N ha−1 year−1 was inadequate for maintaining soil N balance, and amendment of soil with organic source could not stop the loss of soil P and K. The applying rates of 150 kg N ha−1 year−1, 25 kg P ha−1 year−1, and 60 kg K ha−1 year−1 combined with 2–3 t ha−1 organic manure were recommended to maintain soil fertility level. The nitrogen use efficiency (NUE) was greatly improved in the years with proper precipitation and balanced fertilization. Higher NUE and grain yields were achieved under NPK and NPKM treatments in years with normal precipitation. The results clearly demonstrated that both organic and mineral fertilizers were needed to increase crop production, improve NUE and maintain soil fertility level.
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Effect of different fertilization system on soil Nutrient Budget
Ying yong sheng tai xue bao = The journal of applied ecology, 2002Co-Authors: Lu Zhang, Xiuyan Yin, Shanmin ShenAbstract:A long-term experiment was carried out on a damp palm soil about ten years under the condition of Nutrient recycling and reutilization. The quantity of crop Nutrients transferred from the system, and the Nutrient Budget of N, P and K in soil were studied. The results of a ten-year field experiment indicated that the use of Nutrients recycled in the farming systems with appropriate amount of fertilizers applied according to the soil Nutrient supplying ability could not only produce high crop yield, but also balance the soil Nutrient Budget, so that, there were no significant surplus of Nutrients (mainly inorganic nitrogen) which might emit or leach out of soil into environment.
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Changes of crop yield and soil fertility under long-term application of fertilizer and recycled Nutrients in manure on a black soil III. Soil Nutrient Budget
Ying yong sheng tai xue bao = The journal of applied ecology, 2002Co-Authors: Hongxiang Liu, Lu Zhang, Delu Wang, Shouyu Wang, Kai Meng, Xiaozeng Han, Shanmin ShenAbstract:The Nutrient Budget of fertilization models under different treatments was calculated using data from a field experiment over the period of 1985-1999. The results indicated that application of nitrogen fertilizer accelerated a large deficit of soil phosphorus, and the use of nitrogen and phosphorus accelerated the deficit of potassium. The experimental data demonstrated the appearance of a large area of soil deficit of phosphorus from 1970s and of potassium from 1980s in China. Nutrient recycled in farming system improved soil Nutrient Budget, but could not meet the Nutrient requirements from high-yield crops. The use of recycled Nutrients with an appropriate use of fertilizers according to the soil fertility could produce higher crop yields, balance soil Nutrient Budget, and not cause surplus Nutrients to emit into environment.
John E. D. Fox - One of the best experts on this subject based on the ideXlab platform.
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Nutrient Budget of a montane evergreen broad‐leaved forest at Ailao Mountain National Nature Reserve, Yunnan, southwest China
Hydrological Processes, 2003Co-Authors: Wen-yao Liu, John E. D. FoxAbstract:Hydrological fluxes and associated Nutrient Budget were studied during a 2 year period (1998–99) in a montane moist evergreen broad-leaved forest at Ailao Mountain, Yunnan. Water samples of rainfall, throughfall, and stemflow, and of surface runoff, soil water, and stream flow were collected bimonthly to determine the concentration and fluxes of Nutrients. Soil Budgets were determined from the difference between precipitation input (including Nutrient leaching from canopy) and output via runoff and drainage. The forest was characterized by low canopy interception and surface runoff, and high percolation and stream flow. Concentrations of Nutrients were increased in throughfall and stemflow compared with precipitation. Surface runoff and drainage water had higher Nutrient concentrations than precipitation and stream water. Total nitrogen and NH4+-N concentrations were higher in soil water than stream water, whereas K+, Ca2+, and Mg2+ concentrations were lower in the former than the latter. Annual Nutrient fluxes decreased with soil depth following the pattern of water flux. Annual losses of most Nutrient elements via stream flow were less than the corresponding inputs via throughfall and stemflow, except for calcium, for which solute loss was greater than the inputs via precipitation. Leaching losses of that element may be compensated by weathering. Losses of nitrogen, phosphorus, potassium, magnesium, sodium, and sulphur could be replaced through atmospheric inputs. Copyright © 2002 John Wiley & Sons, Ltd.
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Nutrient Budget of a montane evergreen broad leaved forest at ailao mountain national nature reserve yunnan southwest china
Hydrological Processes, 2003Co-Authors: Wen-yao Liu, John E. D. FoxAbstract:Hydrological fluxes and associated Nutrient Budget were studied during a 2 year period (1998–99) in a montane moist evergreen broad-leaved forest at Ailao Mountain, Yunnan. Water samples of rainfall, throughfall, and stemflow, and of surface runoff, soil water, and stream flow were collected bimonthly to determine the concentration and fluxes of Nutrients. Soil Budgets were determined from the difference between precipitation input (including Nutrient leaching from canopy) and output via runoff and drainage. The forest was characterized by low canopy interception and surface runoff, and high percolation and stream flow. Concentrations of Nutrients were increased in throughfall and stemflow compared with precipitation. Surface runoff and drainage water had higher Nutrient concentrations than precipitation and stream water. Total nitrogen and NH4+-N concentrations were higher in soil water than stream water, whereas K+, Ca2+, and Mg2+ concentrations were lower in the former than the latter. Annual Nutrient fluxes decreased with soil depth following the pattern of water flux. Annual losses of most Nutrient elements via stream flow were less than the corresponding inputs via throughfall and stemflow, except for calcium, for which solute loss was greater than the inputs via precipitation. Leaching losses of that element may be compensated by weathering. Losses of nitrogen, phosphorus, potassium, magnesium, sodium, and sulphur could be replaced through atmospheric inputs. Copyright © 2002 John Wiley & Sons, Ltd.
Wen-yao Liu - One of the best experts on this subject based on the ideXlab platform.
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Nutrient Budget of a montane evergreen broad‐leaved forest at Ailao Mountain National Nature Reserve, Yunnan, southwest China
Hydrological Processes, 2003Co-Authors: Wen-yao Liu, John E. D. FoxAbstract:Hydrological fluxes and associated Nutrient Budget were studied during a 2 year period (1998–99) in a montane moist evergreen broad-leaved forest at Ailao Mountain, Yunnan. Water samples of rainfall, throughfall, and stemflow, and of surface runoff, soil water, and stream flow were collected bimonthly to determine the concentration and fluxes of Nutrients. Soil Budgets were determined from the difference between precipitation input (including Nutrient leaching from canopy) and output via runoff and drainage. The forest was characterized by low canopy interception and surface runoff, and high percolation and stream flow. Concentrations of Nutrients were increased in throughfall and stemflow compared with precipitation. Surface runoff and drainage water had higher Nutrient concentrations than precipitation and stream water. Total nitrogen and NH4+-N concentrations were higher in soil water than stream water, whereas K+, Ca2+, and Mg2+ concentrations were lower in the former than the latter. Annual Nutrient fluxes decreased with soil depth following the pattern of water flux. Annual losses of most Nutrient elements via stream flow were less than the corresponding inputs via throughfall and stemflow, except for calcium, for which solute loss was greater than the inputs via precipitation. Leaching losses of that element may be compensated by weathering. Losses of nitrogen, phosphorus, potassium, magnesium, sodium, and sulphur could be replaced through atmospheric inputs. Copyright © 2002 John Wiley & Sons, Ltd.
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Nutrient Budget of a montane evergreen broad leaved forest at ailao mountain national nature reserve yunnan southwest china
Hydrological Processes, 2003Co-Authors: Wen-yao Liu, John E. D. FoxAbstract:Hydrological fluxes and associated Nutrient Budget were studied during a 2 year period (1998–99) in a montane moist evergreen broad-leaved forest at Ailao Mountain, Yunnan. Water samples of rainfall, throughfall, and stemflow, and of surface runoff, soil water, and stream flow were collected bimonthly to determine the concentration and fluxes of Nutrients. Soil Budgets were determined from the difference between precipitation input (including Nutrient leaching from canopy) and output via runoff and drainage. The forest was characterized by low canopy interception and surface runoff, and high percolation and stream flow. Concentrations of Nutrients were increased in throughfall and stemflow compared with precipitation. Surface runoff and drainage water had higher Nutrient concentrations than precipitation and stream water. Total nitrogen and NH4+-N concentrations were higher in soil water than stream water, whereas K+, Ca2+, and Mg2+ concentrations were lower in the former than the latter. Annual Nutrient fluxes decreased with soil depth following the pattern of water flux. Annual losses of most Nutrient elements via stream flow were less than the corresponding inputs via throughfall and stemflow, except for calcium, for which solute loss was greater than the inputs via precipitation. Leaching losses of that element may be compensated by weathering. Losses of nitrogen, phosphorus, potassium, magnesium, sodium, and sulphur could be replaced through atmospheric inputs. Copyright © 2002 John Wiley & Sons, Ltd.
Ravi Fotedar - One of the best experts on this subject based on the ideXlab platform.
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Effects of feeding rates on the growth, water quality and Nutrient Budget of western king prawn (Penaeus latisulcatus Kishinouye) reared in recirculating aquaculture systems
Aquaculture Research, 2012Co-Authors: Van Khoi Le, Ravi Fotedar, Martin S KumarAbstract:Feed rate is one of the important variables considered for the improvement in production of prawns. The effects of four feeding rates on growth, water quality and the Nutrient Budget of Penaeus latisulcatus were investigated for 98 days. The specific growth rate (SGR) at 3.0% feed rate was significantly higher than at all higher feed rates, and there was no significant difference in SGR between 4.5%, 6% and 7.5%. Total ammonia nitrogen concentrations in all treatments remained low in the safe range for prawn culture. Dissolved inorganic nitrogen and nitrate nitrogen were significantly higher (P < 0.05) in prawn tanks received feed rates of 6.0% and 7.5%. Total phosphorus and the soluble reactive phosphorus linearly increased with the progression of the trial and feeding rates. Nutrient conversion rates were significantly higher (P < 0.05) in prawns receiving the feeding rate of 3.0% than feeding rates of 6.0% and 7.5%. The lowest food conversion ratio was recorded at feeding rates of 3% and 4.5%. Nutrient Budget showed that 6.01–15.99% nitrogen and 4.53–9.29% phosphorus of the Nutrient inputs were retained in the prawn biomass. The results indicated that the growth and Nutrient conversion rate may not increase with the increase above 3.0% of biomass per day.
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effects of stocking density on the Nutrient Budget and growth of the western king prawn penaeus latisulcatus kishinouye in a recirculating aquaculture system
Aquaculture Research, 2010Co-Authors: Le Van Khoi, Ravi FotedarAbstract:Intensification in the commercial culture of prawns can have a significant impact on the water quality and hence on the survival, growth and the surrounding environment. The present study aims to evaluate the effects of stocking density on the water quality and performance of the western king prawns (Penaeus latisulcatus) and the Nutrient Budget of the culture environment. Four stocking densities of 4, 8, 16 and 32 prawns m−2 were tested in 12 recirculating systems. Prawn weight and specific growth rate increased with decreasing stocking density, while the survival rate showed the reverse trend. The mean total ammonia nitrogen, nitrate nitrogen, total phosphorus and soluble reactive phosphorus were significantly higher (P<0.05) at the higher stocking density. The Nutrient Budget revealed that the prawns could assimilate only 9.34–20.13% nitrogen and 4.97–11.25% phosphorus of the total Nutrient inputs. The drained water at harvest was the major sink of phosphorus and nitrogen at stocking densities of 4, 8 and 16, which accounted for 45.59–64.82% and 44.28–65.62% of the total inputs, respectively, while a significant proportion of nitrogen sunk into the sediment at 32 prawns m−2. The study suggested that the stocking densities of western king prawns can be up to 16 prawns m−2 in the recirculating water environment.
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Effects of stocking density on the Nutrient Budget and growth of the western king prawn (Penaeus latisulcatus Kishinouye) in a recirculating aquaculture system
Aquaculture Research, 2010Co-Authors: Le Van Khoi, Ravi FotedarAbstract:Intensification in the commercial culture of prawns can have a significant impact on the water quality and hence on the survival, growth and the surrounding environment. The present study aims to evaluate the effects of stocking density on the water quality and performance of the western king prawns (Penaeus latisulcatus) and the Nutrient Budget of the culture environment. Four stocking densities of 4, 8, 16 and 32 prawns m−2 were tested in 12 recirculating systems. Prawn weight and specific growth rate increased with decreasing stocking density, while the survival rate showed the reverse trend. The mean total ammonia nitrogen, nitrate nitrogen, total phosphorus and soluble reactive phosphorus were significantly higher (P
Danilo Dos Santos Rheinheimer - One of the best experts on this subject based on the ideXlab platform.
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soil fertility and Nutrient Budget after 23 years of different soil tillage systems and winter cover crops in a subtropical oxisol
Geoderma, 2017Co-Authors: Tales Tiecher, Ademir Calegari, Laurent Caner, Danilo Dos Santos RheinheimerAbstract:Abstract Growing cover crops to recycle soil Nutrients in no-tillage systems provide Nutrients accumulation in more labile forms in the soil surface reducing the demand for fertilizers. This study aimed to evaluate the long-term (23-yrs) effect of soil tillage systems and winter cover crops on ( i ) soil acidity, ( ii ) Nutrient availability, and ( iii ) P and K Budget in a subtropical Oxisol from Southern Brazil. The experiment was established in 1986 with six winter treatments (blue lupine, hairy vetch, oat, radish, wheat, and fallow) and two tillage systems (conventional tillage - CT and no-tillage - NT) in a very clayey Rhodic Hapludox in Southern Brazil. Nutrient availability (P, K, Ca, and Mg) and soil acidity (pH, potential acidity, base and Al saturation) were evaluated in five soil depths (0–5, 5–10, 10–20, 20–30, and 30–40 cm). Nutrient Budget was calculated considering the inputs (amount of P and K applied via fertilizer) and outputs of P and K from the system (exported by the grains), and the soil available P and K before and after 23-years of experiment. Continuous NT system for 23-years resulted in higher soil fertility in the topsoil (0–10 cm) compared to CT, but with some limitations of Nutrient availability and soil acidity below 10 cm depth. Long-term NT builds up a strong gradient of Nutrient availability, with higher concentration of Nutrients on the soil surface layers that abruptly decrease with soil depth, unlike CT. Surface application of lime in NT reduced soil acidity up to 20 cm compared to CT. The Budget of P was negative for all treatments, highlighting the P-sink behavior of this strongly weathered subtropical Oxisol. However, NT system resulted in less negative Budget compared to CT and, therefore, higher efficiency of use of P. Growing cover crops in the winter is effective to increase P and K availability through plant cycling, but the plants grown in winter did not affect soil acidity. Nutrient cycling by winter cover crops reduced P and K losses, especially when the soil is not plowed. Fallow in the winter decreases the use efficiency of P and K. Among the cover crops tested, black oat stood out by its greater production of biomass, resulting in higher P and K availability in the soil surface. Lupine resulted in a greater cycling of P possibly due to its ability to absorb P from less labile forms in the soil.
