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Fertilizers uptake

Figure 4.10 shows one use. To check the action of a fertilizer, researchers incorporate radioactive isotopes into the molecules of the fertilizer and then apply the fertilizer to plants. The amount taken up by the plants can be measured with radiation detectors. From such measurements, scientists can tell farmers how much fertilizer to use, because fertilizer uptake is a physical and chemical process that is not affected by the radioactivity of the materials involved. [Pg.115]

Tracking fertilizer uptake with a radioactive isotope. [Pg.115]

Recent studies in highly erodible loess soil of China s Shaanxi Province confirm the advantages of subsurface application. Nitrogen fertilizer uptakes were just 18% for surface application to com and 25% to wheat, but the rates rose to between 33 and 36% for subsurface placements see Rees, R. M., et al. 1997. The effects of fertilizer placement on nitrogen uptake and yield of wheat and maize in Chinese loess soils. Nutrient Cycling in Agroecosystems 47 81-91. [Pg.318]

Agricultural Use. Citric acid and its ammonium salts are used to form soluble chelates of iron, copper, magnesium, manganese, and zinc micronutrients in Hquid fertilizers (97—103). Citric acid and citrate salts are used in animal feeds to form soluble, easily digestible chelates of essential metal nutrients, enhance feed flavor to increase food uptake, control gastric pH and improve feed efficiency. [Pg.185]

Table 4 Fate of nitrogen fertilizer applied in exeess of erop uptake in England and Wales, 1977-1986. Caleulated using the assumptions listed in the text... Table 4 Fate of nitrogen fertilizer applied in exeess of erop uptake in England and Wales, 1977-1986. Caleulated using the assumptions listed in the text...
One of the exciting features of the direct DNA delivery system is that it does not rely on an infection. The limited host range of other vector delivery systems is therefore irrelevant, and the way is opened for genetic engineering of cereals. Cereal protoplasts are equally amenable to uptake of foreign DNA after electroporation and the system therefore has potential for use with the major crop species. However, there is at present one drawback, namely that for cereals it has not yet proved possible to grow fertile whole plants from the genetically transformed cells. [Pg.139]

D. J. Greenwood and T. V. Karpinets, Dynamic model for the effects of K-fertilizer on crop growth, K-uptake and soil-K in arable cropping I. Description of the model. Soil Use Mift. i34 19, (1997). [Pg.369]

Two studies have suggested that quackgrass (Agropyron repens L.) can reduce K uptake by maize (Zea mays L.) plants. Bandeen and Buchholtz (11) found that K+, but not N or P0, content of corn was decreased by quackgrass growing with maize. Because high levels of fertilization did not overcome the effect of quackgrass, the authors concluded that competition was not responsible (11, 12). [Pg.163]

Most trace metals may be precipitated with phosphate into insoluble metal phosphates (Table 7.5). Most metal phosphates have low solubility. High localization of phosphates reduces the bioavailability of Zn in arid soils. The banded application of P near the seeds depresses Zn uptake by com (Adriano and Murphy, 1970 Grant and Bailey, 1993), causing Zn deficiency. However, both N and P fertilizers increase Cd concentration in plants. Cadmium and Zn are antagonistic in root uptake and distribution within plants. [Pg.250]

Jiao Y., Bailey L.D., Grant C.A. Effects of phosphorus and zinc fertilizer on cadmium uptake and distribution in flax and durum wheat. J Sci Food Agri 2004 84 777-785. [Pg.340]

Mortvedt J.J., Mays D.A., Osborn G. Uptake by wheat of cadmium and other heavy metal contaminants in phosphate fertilizers. J Environ Qual 1981 10 193-197. [Pg.346]

Kumar K, Gupta SC, Baidoo SK, Chander Y, Rosen CJ (2005) Antibiotic uptake by plants from soil fertilized with animal manure. J Environ Qual 34 2082-2085... [Pg.109]

The use of nitrogen fertilization results in higher content of N-containing compounds, including free amino acids, and also increases in terpene content in wood plants, whilst starch, total carbohydrates, phenylpropanoids and total carbon-based phytochemicals decreased (Koricheva et al., 1998). Higher levels of nitrogen favoured its uptake and increased the nitrate content of the crop, which is critical for salad vegetables and baby foods. [Pg.318]

Nutrient concentration has a marked seasonal variation in the middle Ebro. Nutrient loads transported by the river are relevant during the high flow season (December-April), while nitrate inputs from agriculture can also be relevant. In this period, crop fertilization is carried out, precipitation is higher, and plant nitrogen uptake is lower [37], Although nutrient loads are high, dilution causes NO3 and... [Pg.13]

The availability of selenium to plants may be lessened by modem agricultural practices, eventually contributing to selenium deficiency in animal consumers. For example, fertilizers containing nitrogen, sulfur, and phosphorus all influence selenium uptake by plants through different... [Pg.1602]

ABSTRACT The locations, magnitudes, variations and mechanisms responsible for the atmospheric C02 sink are uncertain and under debate. Previous studies concentrated mainly on oceans, and soil and terrestrial vegetation as sinks. Here, we show that there is an important C02 sink in carbonate dissolution, the global water cycle and photosynthetic uptake of DIC by aquatic ecosystems. The sink constitutes up to 0.82 Pg C/a 0.24 Pg C/a is delivered to oceans via rivers and 0.22 Pg C/a by meteoric precipitation, 0.12 Pg C/a is returned to the atmosphere, and 0.23 Pg C/a is stored in the continental aquatic ecosystem. The net sink could be as much as 0.70 Pg C/a, may increase with intensification of the global water cycle, increase in C02 and carbonate dust in atmosphere, reforestation/afforestation, and with fertilization of aquatic ecosystems. Under the projection of global warming for the year 2100, it is estimated that this C02 sink may increase by 22%, or about 0.18 Pg c/a. [Pg.477]


See other pages where Fertilizers uptake is mentioned: [Pg.253]    [Pg.115]    [Pg.227]    [Pg.253]    [Pg.115]    [Pg.227]    [Pg.358]    [Pg.31]    [Pg.15]    [Pg.28]    [Pg.33]    [Pg.33]    [Pg.573]    [Pg.435]    [Pg.338]    [Pg.339]    [Pg.146]    [Pg.139]    [Pg.356]    [Pg.45]    [Pg.66]    [Pg.120]    [Pg.178]    [Pg.360]    [Pg.40]    [Pg.251]    [Pg.15]    [Pg.397]    [Pg.402]    [Pg.738]    [Pg.654]    [Pg.656]    [Pg.1480]    [Pg.1508]    [Pg.1603]    [Pg.387]   
See also in sourсe #XX -- [ Pg.137 , Pg.184 , Pg.185 , Pg.186 , Pg.187 , Pg.207 , Pg.209 , Pg.210 , Pg.216 ]




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