The article contains sections titled: 1. Aminophenols 1.1. Physical Properties 1.2. Chemical Properties 1.3. Production 1.3.1. Reduction 1.3.2. Substitution 1.3.3. Purification 1.4. Storage and Handling 1.5. Analysis 1.6. Environmental Aspects 1.7. Uses 1.8. Toxicology 2. Aminophenol Derivatives 2.1. Derivatives of 2‐Aminophenol 2.2. Derivatives of 3‐Aminophenol 2.3. Derivatives of 4‐Aminophenol
Effects of disturbance on the N cycle in a 450‐year‐old Douglas‐fir stand (Pseudotsuga menziesii) were studied in an experiment in which herbicides were used to kill all vegetation while minimally disturbing the litter layer and soil. Nitrogen concentration in falling foliage was greater on the treated area than on a control area, as was soil moisture. Nitrate and Kjeldahl N concentrations in the soil solution were greater on the treated than on the untreated area, but only at or below the bottom of the rooting zone (≥1‐m depth). On the untreated area, nitrate was present in solution in significant amounts only at the 2‐m depth.
Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings at a western Oregon nursery were fertilized in October 1983 with ammonium nitrate and harvested for biochemical analyses on four dates over autumn and winter 1983–1984. Free amino acid and total nitrogen concentrations in the needles of fertilized seedlings showed a pronounced increase 1 month after fertilization. Free amino acid concentrations of fertilized seedlings decreased in needles during winter but remained stable in stems and fine roots. Just before budbreak in mid-March, free amino acid concentrations increased significantly in stems and fine roots. Total nitrogen concentrations increased 1 month after fertilization, remained stable throughout winter, and tended to decrease or remain stable just before budbreak. Starch and total nonstructural carbohydrate concentrations of needles and stems of fertilized seedlings were lower just before budbreak and sugar concentrations of fine roots of fertilized seedlings were lower when data from all harvests were combined. The reduction in carbohydrate reserves following fertilization probably reflects increased respiration associated with the synthesis and maintenance of higher levels of enzymes.
October-fertilized and unfertilized 2-0 Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings were outplanted the following February. Half of each planting block was seeded with grass to induce water stress during the typical summer drought. Sucrose was applied to soil around each seedling to limit availability of nitrogen to tree roots. Fertilized seedlings broke bud 9–10 days earlier, produced more shoot growth, and, as shown in later harvests, had higher relative growth rates than unfertilized seedlings. However, initial differences in growth response were due primarily to the earlier budbreak. Seedlings growing with grass had predawn water potentials of −1.5 MPa by early August; by September 3, unfertilized seedlings growing with grass were significantly more stressed than any others. Although free amino acid and total nitrogen concentrations were higher in fertilized than unfertilized seedlings when planted, they became equal by the end of one growing season. However, fertilized seedlings contained more free amino acids and nitrogen because of their greater size. Grass competition affected both seedling nitrogen and carbohydrate chemistry. After one growing season, fertilized seedlings had greater height increment, shoot growth, leaf area, relative growth rate, and production per unit nitrogen. Although autumn fertilization benefited these Douglas-fir seedlings, negative effects could result from carbohydrate depletion because of increased respiration or from frost damage because of earlier budbreak.
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