Losses of nutrients

The burning of slash following deforestation, whether intentional or unintentional, results in far greater direct and indirect losses of nutrients than deforestation alone. This is particularly true in many tropical forests where only a small fraction (if any) of the aboveground biomass is removed prior to burning. Carbon losses from slash fires in the tropical dry forest were 4-5 fold greater than C losses from wood export (Table IV) (55). Slash fires in tropical dry forests resulted in N losses of 428-500 kg ha whereas fuel wood export of the relatively N-poor coarse woody debris amounted to approximately 41 kg N ha" Losses of P increase with increasing fire severity. P losses of 10-77 kg ha" as a result of severe fires is not uncommon (Table TV) (53, 58, 60). 

Fresh-cut fruits and vegetables are highly perishable products because of their intrinsic characteristics and the minimal processing (Ayala-Zavala and others 2008a). Microbial growth, decay of sensory attributes, and loss of nutrients are among the... 

From the legal point of view, antioxidants are substances which prolong the shelf-life of foodstuffs by protecting them against deterioration caused by oxidation, such as fat rancidity, colour changes and loss of nutrient value. Hundreds of compounds, both natural and synthesised, have been reported to possess antioxidant properties. Their use in food, however, is limited by certain obvious requirements, not the least of which is adequate proof of safety. 

An example of the fragile nutrient balance in peat bogs is given in Table 7.2 for a blanket bog in northern England. The table shows the losses of N through erosion of the peat, and the losses of nutrient cations through leaching and removal in stream water. 

Vellar, O.D. (1968) Studies on sweat losses of nutrients. I. Iron content of whole body sweat and its association with other sweat constituents, serum iron levels, hematological indices, body surface area, and sweat rate. Scand. J. Clin. Lab. Invest. 21, 157-167,... 

The increasing conversion of rain forest to pasture was sharply criticized by environmental scientists. Because of the very low fertility of the soils, maximum carrying capacity the first year following conversion of forest to pasture was predicted to be only about 0.4 head of cattle per hectare. Rapid loss of nutrients and fixation of phosphoms caused the maximum possible stocking rate... 

After a spate of findings that uptake did not match the net loss of nutrient during... 

Thompson (98) investigated the loss of nutrients from milk after pasteurization and sterilization. A portion of his results are found in Table V. HTST (72°C for 15 s) pasteurization of the fluid milk prior... 

Table V. Loss of Nutrients in Milk During Processing...

It has been suggested that, during preparation of food for the table either in or out of the home, losses of nutrients occur that surpass those incurred during processing (116). An extensive review of the literature done in 1960 (117), which was updated in 1975 ( 92), revealed that few new data have been reported in the intervening years. Erdman (57) suggested that more information, particularly on the eflFects of cooking procedures on nutrient retention, was necessary. 

Acid rain increases the acidity of some types of soil, resulting in the removal of essential nutrients from the soil. The loss of nutrients adversely affects the area s vegetation, leaving trees and other plants with less resistance to disease, insects, and bad weather. Acid rain also increases the acidity of streams, rivers, and lakes, which can kill or harm aquatic life. As Figure 26-8 shows, damage to trees and to outdoor surfaces can be extensive. The acid in precipitation reacts with CaC03, the major component of marble and limestone. What products are produced by this reaction ... 

Loss of nutrients and deterioration of dried fish due to the attack by flies, mites, and beetles... 

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