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Mayela MONGE-MUOZ Segundo URQUIAGA Christoph MLLER Juan Carlos CAMBRONEROHEINRICHS Mohammad ZAMAN Cristina CHINCHILLA-SOTO Azam BORZOUEI Khadim DAWAR Carlos E. RODRGUEZ-RODRGUEZ Ana Gabriela PREZ-CASTILLO 《土壤圈》2021,31(2):303-313
In the tropics,frequent nitrogen(N)fertilization of grazing areas can potentially increase nitrous oxide(N2O)emissions.The application of nitrification inhibitors has been reported as an effective management practice for potentially reducing N loss from the soil-plant system and improving N use efficiency(NUE).The aim of this study was to determine the effect of the co-application of nitrapyrin(a nitrification inhibitor,NI)and urea in a tropical Andosol on the behavior of N and the emissions of N2O from autotrophic and heterotrophic nitrification.A greenhouse experiment was performed using a soil(pH 5.9,organic matter content 78 g kg-1,and N 5.6 g kg-1)sown with Cynodon nlemfuensis at 60%water-filled pore space to quantify total N2O emissions,N2O derived from fertilizer,soil ammonium(NH4+)and nitrate(NO3-),and NUE.The study included treatments that received deionized water only(control,NI).No significant differences were observed in soil NH4+content between the UR and UR+NI treatments,probably because of soil mineralization and NO3-produced by heterotrophic nitrification,which is not effectively inhibited by nitrapyrin.After 56 d,N2O emissions in UR(0.51±0.12 mg N2O-N concluded that the soil organic N mineralization and heterotrophic nitrification are the main processes of NH4+and NO3-production.Additionally,it was found that N2O emissions were partially a consequence of the direct oxidation of the soil's organic N via heterotrophic nitrification coupled to denitrification.Finally,the results suggest that nitrapyrin would likely exert significant mitigation on N2O emissions only if a substantial N surplus exists in soils with high organic matter content. 相似文献
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José David Álvarez-Solís Peter M. Rosset Blanca Mayela Díaz-Hernández Héctor Plascencia-Vargas Robert A. Rice 《Biology and Fertility of Soils》2007,43(3):379-386
In the highlands of Chiapas, southern Mexico, soil texture and soil chemical properties were measured in 70 agricultural fields
covering a range of slope positions and managements. Fields represented four corn cropping systems: long fallow, short fallow,
pasture–cultivation rotation, and annual continuous cultivation, in addition to fallow at rest (forest, shrubland, and pastures).
Fields were located in four slope positions (upper, middle, and lower slopes, and doline floor) in a karst landscape developed
on limestone with additions of acid volcanic ashes. Distribution of clays and sands were related to the toposequence and the
percentage of clay fraction increased from upper slope to doline floor. Sand presented a reverse pattern. Some soil chemical
properties also vary in a characteristic way along the toposequence. Exchangeable Ca2+ and Mg2+ effective cation exchange capacity (ECEC) and pH were higher in the doline floor than in the other slope positions. Soil
organic matter and total N contents were 30.4 and 35.2% higher under long fallow than under annual continuous cultivation.
Soil Olsen P was greater under cultivation than under fallow (irrespective of the cropping system), with the highest values
under annual continuous cultivation (16.2±8.3 mg kg−1) and the lowest in the forest (5.3±2.5 mg kg−1). Exchangeable K+ was 74 and 51% higher in cultivated plots of the long and the short fallow than under forest and shrubland, respectively.
Exchangeable Ca2+ and Mg2+ and ECEC did not vary significantly among the cropping systems. Inputs of basic cations through burning of tree and shrub
vegetation increased the soil pH. These results indicate that land use intensification is leading to a decline in soil organic
matter and total N, whereas Olsen P increased with intensification due to the continuous application of P fertilizers and
sheep manure as soil conditioners in intensively cultivated fields. 相似文献
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