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Inorganic Fertilizer (inorganic + fertilizer)
Selected AbstractsThe role of Variovorax and other Comamonadaceae in sulfur transformations by microbial wheat rhizosphere communities exposed to different sulfur fertilization regimesENVIRONMENTAL MICROBIOLOGY, Issue 6 2008Achim Schmalenberger Summary Sulfonates are a key component of the sulfur present in agricultural soils. Their mobilization as part of the soil sulfur cycle is mediated by rhizobacteria, and involves the oxidoreductase AsfA. In this study, the effect of fertilization regime on rhizosphere bacterial asfA distribution was examined at the Broadbalk long-term wheat experiment, Rothamsted, UK, which was established in 1843, and has included a sulfur-free treatment since 2001. Direct isolation of desulfonating rhizobacteria from the wheat rhizospheres led to the identification of several Variovorax and Polaromonas strains, all of which contained the asfA gene. Rhizosphere DNA was isolated from wheat rhizospheres in plots fertilized with inorganic fertilizer with and without sulfur, with farmyard manure or from unfertilized plots. Genetic profiling of 16S rRNA gene fragments [denaturing gradient gel electrophoresis (DGGE)] from the wheat rhizospheres revealed that the level of inorganic sulfate in the inorganic fertilizer was correlated with changes in the general bacterial community structure and the betaproteobacterial community structure in particular. Community analysis at the functional gene level (asfA) showed that 40% of clones in asfAB clone libraries were affiliated to the genus Variovorax. Analysis of asfAB -based terminal restriction fragment length polymorphism (T-RFLP) fingerprints showed considerable differences between sulfate-free treatments and those where sulfate was applied. The results suggest the occurrence of desulfonating bacterial communities that are specific to the fertilization regime chosen and that arylsulfonates play an important role in rhizobacterial sulfur nutrition. [source] Soilscape and land-use evolution related to drift sand movements since the bronze age in Eastern Jutland, DenmarkGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 2 2007Jari Hinsch Mikkelsen Quarry faces several kilometers long in the Glesborg area in Denmark show that Bronze Age farmers used a sustainable land-use system. Despite nutrient-poor soils, the Glesborg area was under a rotation system in which cropland alternated with grassland. Soil fertility was improved by the addition of household waste and probably also by locally obtained inorganic fertilizer. The soil surface was very stable, and local drift sand movement was limited. Toward the end of the Bronze Age, the landscape changed dramatically with the arrival of overwhelming amounts of drift sand, and farmsteads were abandoned. Subsequent land use on these poor fine sandy soils was no longer capable of maintaining a stable soil surface, and frequent erosion/sedimentation events of more local importance took place. The post-Bronze Age landscape may have been mainly a shifting mosaic of heathland with some temporary arable fields and deflation/accumulation areas. This landscape persisted up to about 200 years ago, when afforestation programs started. © 2007 Wiley Periodicals, Inc. [source] The conservation management of upland hay meadows in Britain: a reviewGRASS & FORAGE SCIENCE, Issue 4 2005R. G. Jefferson Abstract Upland hay meadows conforming to MG3 in the National Vegetation Classification of the UK are a rare habitat in Britain and are largely confined to upland valleys in northern England. Agricultural intensification, particularly ploughing and reseeding and a shift from hay-making to silage production over the last 50 years, has resulted in large losses of species-rich upland hay meadows. Remaining species-rich meadows have been the focus of much nature conservation effort resulting in many of the species-rich sites being protected by statutory designations or through voluntary agri-environment scheme agreements. Research and monitoring has tended to confirm that species richness is maximized by management involving spring and autumn grazing, a mid-July hay cut, no inorganic fertilizer and possibly low levels of farmyard manure. Deviations from this regime result in a loss of species richness. Restoration of semi-improved grassland to swards resembling species-rich MG3 also requires a similar regime but is also dependent on the introduction of seed of appropriate species. The role of Rhinanthus minor as a tool for manipulating meadow biodiversity during restoration management is discussed. Suggestions for future research are outlined. [source] Effect of Organic and Inorganic Nutrients for Soil Quality Conservation and Yield of Rainfed Low Land Rice in Sub-tropical Plateau RegionJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 5 2006P. Banik Abstract The effect of organic sources of nutrients and inorganic fertilizers, was studied on grain yield of lowland rice and some aspect of soil quality parameters in a field experiment at Agricultural Experimental Farm of Indian Statistical Institute, Giridih, situated at eastern plateau region of India, during consecutive years 1997,2002. Chemical fertilizers and various organic matters were applied to two rice cultivars, Sabita and Subarna. The highest mean grain yield was 3.53 t ha,1 and maximum agronomic efficiency was 60.3 % with the application of inorganic fertilizer followed by cow dung, where 3.47 t ha,1 grain yield was recorded with an agronomic efficiency of 57.5 %. Grain yield of rice recorded under organic sources of nutrients was not significantly different from that of inorganic fertilization though there was improvement in soil quality parameters under organic sources. Soil organic carbon (0.72 %), microbial biomass-C (279.23 ,g g,1 dry soil), urease activity with buffer (33.54 ,g urea hydrolyzed g,1 oven-dry soil) and non-buffer (21.97 ,g urea hydrolyzed g,1 of oven-dry soil) methods and acid phosphatase activity (2.24 ,g para-nitrophenol released g,1 of oven-dry soil) analysed following the harvest of the crop were highest under cow dung manure treatment; the most efficient organic source under the experiment. Mean grain yield of rice was significantly higher in Sabita cultivar over Subarna. The regression analyses among the variables have shown that there was linear relationship among soil parameters and grain yield of rice. [source] Productivity and Sustainability of Cotton (Gossypium hirsutum L.),Wheat (Triticum aestivum L.) Cropping System as Influenced by Prilled Urea, Farmyard Manure and AzotobacterJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 5 2004A. Das Abstract Field experiments were conducted at Indian Agricultural Research Institute, New Delhi, during 2001,2002 and 2002,2003, to study the effect of inorganic, organic and Azotobacter combined sources of N on cotton (Gossypium hirsutum L.) and their residual effect on succeeding wheat (Triticum aestivum L.) crop. The results indicated considerable increase in yield attributes and mean seed cotton yield (2.33 Mg ha,1) with the combined application of 30 kg N and farmyard manure (FYM) at 12 Mg ha,1 along with Azotobacter (M4). The treatment in cotton that included FYM, especially when fertilizer N was also applied could either improve or maintain the soil fertility status in terms of available N, P and K. Distinct increase in yield attributes and grain yield of wheat was observed with the residual effect of integrated application of 30 kg N ha,1 + FYM at 12 Mg ha,1 + Azotobacter. Direct application of 120 kg N ha,1 resulted 67.4 and 17.7 % increase in mean grain yield of wheat over no N and 60 kg N ha,1, respectively. Integrated application of organic and inorganic fertilizer is therefore, recommended for higher productivity and sustainability of the cotton,wheat system. [source] Impact of Phosphorus from Dairy Manure and Commercial Fertilizer on Perennial Grass Forage ProductionJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 6 2003E. A. Mikhailova Abstract Increased recovery and recycling of manure phosphorus (P) by crops on dairy farms is needed to minimize environmental problems. The main objective of this study was to compare P utilization by orchardgrass (Dactylis glomerata L.) and tall fescue (Festuca arundinaceae Schreb.) from dairy manure or inorganic fertilizer. The study was conducted from 1994 to 2000 at the Cornell University Baker Farm, Willsboro, NY, on a somewhat poorly drained Kingsbury clay (very,fine, illitic, mesic Aeric Epiaqualfs). The design was a split-plot in a randomized complete block with two manure rates (16 800 and 33 600 kg ha,1) and one nitrogen (N) fertilizer rate (84 kg N ha,1 at spring greenup and 56 kg N ha,1 prior to each regrowth harvest) as the main plots and grass species as subplots replicated six times. Fertilizer P [Ca(H2PO4)2] was applied to the fertilizer treatment in 1995 and 1996 at 11 kg P ha,1 year,1. Orchardgrass P removal averaged 21 % higher than tall fescue P removal for the spring harvest, but orchardgrass averaged 24 % lower P removal than tall fescue removal for all regrowth harvests from 1995,99. Phosphorus herbage concentration in the fertilizer treatment was in the range of 1.9,2.7 g P kg,1 compared with 2.2,5.3 g P kg,1 in the manure treatments. Seasonal P removal ranged from as low as 9.2 kg P ha,1 to as high as 48.5 kg P ha,1. Morgan extractable soil P in the top 0,0.20 m remained high through 1999, with 29.1 kg P ha,1 at the highest manure rate in tall fescue compared with 8.4 kg P ha,1 measured in 1993 prior to the experiment. In 2000, soil P at the highest manure rate in tall fescue dropped to 10.1 kg P ha,1, following cessation of manure application in 1998. Intensively managed harvested orchardgrass and tall fescue have the potential to remove large quantities of manure P. [source] Loss of phosphorus from soil in semi-arid northern Tanzania as a result of cropping: evidence from sequential extraction and 31P-NMR spectroscopyEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2000D. Solomon Summary In semi-arid northern Tanzania, the native woodland is being rapidly cleared and replaced by low input agriculture. This has resulted in pronounced environmental degradation, and in particular loss of phosphorus (P) from the soil. We have used sequential extraction and 31P-NMR to investigate the effects of land use changes, i.e. native woodland, degraded woodland, cultivation for 3 and 15 years and homestead fields where manure was applied, on the amount and structural composition of P in this soil. Clearing and continuous cultivation reduced both organic and inorganic P in the soil. The difference in the amount of organic P from the bulk soil of the fields cultivated for 3 and 15 years was not statistically significant (P <,0.05), suggesting that most of the depletion in organic P occurred during the first 3 years of cultivation. By contrast, in the homesteads, there was much organic and inorganic P in the soil. The 31P-NMR revealed that cultivation resulted in a 53% depletion of orthophosphate diester P, whereas only a 30% and 39% reduction of orthophosphate monoester P was found in the bulk soil after 3 and 15 years of cultivation, respectively. These results concur with the suggestion that diester P constitutes more easily mineralizable forms of organic P in soil than does monoester P. Our 31P-NMR also showed that 70% of the inorganic orthophosphate P was depleted from the coarse and fine sand separates as a result of cultivation. The influence of clearing and subsequent cropping on the amount and forms of P was more pronounced in the coarse and fine sand than in the silt and clay, stressing the importance of particle size and chemical properties such as organic matter and oxides in the availability of P in this soil. Our results show that the current low input agricultural practice is not sustainable, and that practices must be developed to combat the ongoing degradation of the soil. A combined use of available organic materials such as animal manure with the judicious use of inorganic fertilizers can replenish the soil's fertility. [source] Effect of Organic and Inorganic Nutrients for Soil Quality Conservation and Yield of Rainfed Low Land Rice in Sub-tropical Plateau RegionJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 5 2006P. Banik Abstract The effect of organic sources of nutrients and inorganic fertilizers, was studied on grain yield of lowland rice and some aspect of soil quality parameters in a field experiment at Agricultural Experimental Farm of Indian Statistical Institute, Giridih, situated at eastern plateau region of India, during consecutive years 1997,2002. Chemical fertilizers and various organic matters were applied to two rice cultivars, Sabita and Subarna. The highest mean grain yield was 3.53 t ha,1 and maximum agronomic efficiency was 60.3 % with the application of inorganic fertilizer followed by cow dung, where 3.47 t ha,1 grain yield was recorded with an agronomic efficiency of 57.5 %. Grain yield of rice recorded under organic sources of nutrients was not significantly different from that of inorganic fertilization though there was improvement in soil quality parameters under organic sources. Soil organic carbon (0.72 %), microbial biomass-C (279.23 ,g g,1 dry soil), urease activity with buffer (33.54 ,g urea hydrolyzed g,1 oven-dry soil) and non-buffer (21.97 ,g urea hydrolyzed g,1 of oven-dry soil) methods and acid phosphatase activity (2.24 ,g para-nitrophenol released g,1 of oven-dry soil) analysed following the harvest of the crop were highest under cow dung manure treatment; the most efficient organic source under the experiment. Mean grain yield of rice was significantly higher in Sabita cultivar over Subarna. The regression analyses among the variables have shown that there was linear relationship among soil parameters and grain yield of rice. [source] Rural nonfarm activities and agricultural crop production in NigeriaAGRICULTURAL ECONOMICS, Issue 2 2009Gbemisola Oseni Nigeria; Rural nonfarm activities; Agricultural crop expenditures; Credit constraints Abstract Although most rural households are involved in the farm sector, the nonfarm sector has grown significantly in recent decades, and its role in rural development has become increasingly important. This article examines the effect of participation in nonfarm activities on crop expenses of farm households in Nigeria. The relationship is modeled using a nonseparable agricultural household model that suggests that participating in nonfarm activities can relax the credit constraints facing farm households and reduce risk thereby helping households improve farm production and smooth consumption over time. The results show that participation in nonfarm activities by Nigerian farmers has a positive and significant effect on crop expenses and in particular on payments for hired labor and inorganic fertilizers. Separate analysis of the six geopolitical zones in Nigeria indicates that it is in the South-South and South-East zones where nonfarm participation appears to induce more hiring of labor. The results support the hypothesis that nonfarm participation helps relax liquidity constraints but suggests how that liquidity is used is zone-specific. In general, the results also indicate that liquidity is used more to pay for inputs into staple production as opposed to cash crops. [source] Impact of organic and inorganic fertilizers on yield, taste, and nutritional quality of tomatoesJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2006Anuschka Heeb Abstract In a greenhouse experiment, tomato plants were grown in sand culture to test whether different fertilization regimes (mineral or organic fertilizers) at low (500 mg N plant,1 week,1) and high (750 mg N plant,1 week,1) nitrogen levels affected yield, nutritional quality, and taste of the fruits. In the mineral-fertilizer treatments, nitrate- or ammonium-dominated nutrient solutions were used. Organic fertilizer was supplied as fresh cut grass-clover mulch (a total of 2.4,kg and 3.6,kg were given per plant at low and high N level, respectively) without (orgN) and with additional sulfur fertilization (orgN+S). Yields of red tomatoes from the organically fertilized plants were significantly lower (1.3,1.8,kg plant,1) than yields from plants that received mineral fertilizer (2.2,2.8,kg plant,1). At the final harvest, yields of green tomatoes in the organic treatment with extra sulfur were similar (1.1,1.2,kg plant,1) to the NO -dominated treatments at both nutrient levels and the NH -dominated treatment at high nutrient level. Organic fertilizers released nutrients more slowly than mineral fertilizers, resulting in decreased S and P concentrations in the leaves, which limited growth and yield in the orgN treatments. Analysis of tomato fruits and plants as well as taste-test results gave no conclusive answer on the relationship between sugar or acid contents in the fruits, macronutrient content of plant leaves and fruits, and perceived taste. Sugar contents were higher in the fruits given mineral fertilizer, whereas acid contents were higher in the fruits given organic fertilizer. Preference in taste was given to the tomatoes from plants fertilized with the nitrate-dominated nutrient solution and to those given organic fertilizer with extra sulfur. Thus, a reduction in growth, which was expected to lead to a higher concentration of compounds like sugars and acids, did not result in better taste. Overall, it can be concluded that an appropriate nutrient supply is crucial to reach high yields and good taste. [source] Contribution of nitrification and denitrification to nitrous oxide emissions from soils after application of biogas waste and other fertilizers,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 16 2009Mehmet Senbayram The attribution of nitrous oxide (N2O) emission to organic and inorganic N fertilizers requires understanding of how these inputs affect the two biological processes, i.e. denitrification and nitrification. Contradictory findings have been reported when the effects of organic and inorganic fertilizers on nitrous oxide emission were compared. Here we aimed to contribute to the understanding of such variation using 15N-labelling techniques. We determined the processes producing N2O, and tested the effects of soil moisture, N rates, and the availability of organic matter. In a pot experiment, we compared soil treated with biogas waste (BGW) and mineral ammonium sulphate (Min-N) applied at four rates under two soil moisture regimes. We also tested biogas waste, conventional cattle slurry and mineral N fertilizer in a grassland field experiment. During the first 37 days after application we observed N2O emissions of 5.6,kg N2O-N,ha,1 from soils supplied with biogas waste at a rate of 360,kg,N,ha,1. Fluxes were ca. 5-fold higher at 85% than at 65% water holding capacity (WHC). The effects of fertilizer types and N rates on N2O emission were significant only when the soil moisture was high. Organic fertilizer treated soils showed much higher N2O emissions than those receiving mineral fertilizer in both, pot and field experiment. Over all the treatments the percentage of the applied N emitted as N2O was 2.56% in BGW but only 0.68% in Min-N. In the pot experiment isotope labelling indicated that 65,95% of the N2O was derived from denitrification for all fertilizer types. However, the ratio of denitrification/nitrification derived N2O was lower at 65% than at 85% WHC. We speculate that the application of organic matter in conjunction with ammonium nitrogen first leads to a decrease in denitrification-derived N2O emission compared with soil receiving mineral fertilizer. However, at later stages when denitrification becomes C-limited, higher N2O emissions are induced when the soil moisture is high. Copyright © 2009 John Wiley & Sons, Ltd. [source] Asian carp farming systems: towards a typology and increased resource use efficiencyAQUACULTURE RESEARCH, Issue 6 2002C G J Michielsens Abstract Resource use efficiency in Asian carp farming systems is analysed based on a survey of 2493 farms of nine countries. Multivariate classification of farms by intensity and diversity identified six farm types: four types of specialized aquaculture farms at different levels of intensity, and two types of integrated agriculture,aquaculture systems. Pond-based, specialized semi-extensive systems (using mainly inorganic fertilizers and feeds of off-farm origin), and integrated semi-intensive systems (using feeds and fertilizer of both on and off-farm origin) are by far the most common types, accounting for 59% and 27% of all farms respectively. Specialized semi-extensive systems also show the highest protein and nutrient (N and P) use efficiencies, and among the highest labour use efficiency. Super-intensive cage farms are less efficient in nutrient and labour use, but provide very high returns to land and capital investment. On average, the aquaculture components of integrated agriculture, aquaculture systems are less nutrient, land, and labour efficient than specialized semi-extensive systems. Integrated semi-extensive systems (using organic fertilizers of on-farm origin) are particularly inefficient across all indicators. Hence in practice, gains in overall resource use efficiency through on-farm integration with agricultural production are constrained by the relative inefficiency of the aquaculture subsystems on integrated farms. Although such systems can likely be improved, integration as such is not a panacea to increasing resource use efficiency. Wide variation in resource use efficiency within all systems indicates potential for substantial efficiency gains through improved management regardless of the fundamental choice of system. [source] | ||||||||||||||||||||||