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91.
A preliminary nutrient cycling study quantified total and temporal nutrient inputs via litterfall and pruning residues in two agroforestry systems: (1) Coffea arabica (perennial crop)-Erythrina poeppigiana (leguminous shade tree); and (2) C. arabica-E. poeppigiana-Cordia alliodora with emphasis on the effect of the timber tree C. alliodora. The total annual input of litterfall plus pruning residues was similar in both associations. Total annual input from E. poeppigiana was less than half in the association with C. alliodora than without, but the litterfall from this latter species compensated for the loss. Large differences in the total annual nutrient input of K, Ca and Mg was found between associations, but not for N or P. The amount of nutrients recycled by the associated trees reached the recommended level of fertilizer required for coffee production. The inclusion of C. alliodora within the C. arabica-E. poeppigiana association resulted in a more evenly distributed annual nutrient input.  相似文献   
92.
Purified diets, formulated with and without lecithin and containing either casein or a protein isolated from whole crab, were fed to juvenile lobsters. In order to examine the role of these dietary factors on cholesterol uptake and transport, levels of cholesterol were determined in serum, lipo-protein fractions, tissues, and feces of juvenile lobsters fed the experimental diets. Lobsters fed diets supplemented with lecithin had significantly higher levels of serum and lipoprotein cholesterol than lobsters fed diets without supplemental lecithin regardless of the proteins used. Levels of fecal total cholesterol also were generally greater for lobsters fed lecithin-supplemented diets. Tissue, serum, and fecal levels of intubated radiolabeled cholesterol, however, were not significantly different among diet groups, and apoprotein electrophoretic mobility was not affected by the choice of dietary protein.  相似文献   
93.
The radiographic technique and radiographic and sonographic findings in two green iguanas with egg retention and peritonitis are described. Neither radiography nor ultrasound provided for identification of free eggs within the coelomic structure secondary to presumed oviduct rupture. Gravidity and coelomic effusion were confirmed by both radiography and ultrasound. Radiography and ultrasound are valuable tools in the diagnosis of egg retention and peritonitis in the green iguana.  相似文献   
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Planting three rows of potatoes in a bed the width of two conventional rows offers an easily managed way to increase seed piece populations, with the potential of increasing tuber yield and enhancing tuber quality. A wide bed production system (3 rows of potatoes planted on a 1.9 m flat-topped raised bed) was compared to a conventional-ridged system (1 row of potatoes in sharply sloped ridges on 96 cm centers) in 1996 and 1997 on a Norfolk sandy loam soil and a Portsmouth fine sandy loam soil in eastern North Carolina. Potato plant stands, leaf area index at approximately 9 WAP, yield, and quality were measured. Soil temperature, soil moisture, and cone index, as a measure of soil penetration resistance, were also measured, wide beds were more moist than conventional ridges early in the season. Cone index was greater throughout the root profile in wide beds in two of three tests. The row on the west side of an individual wide bed was most similar to conventional ridges in daily soil temperature fluctuations between minimum and maximum temperatures, and had greater fluctuations than the middle and eastern rows of the wide bed. Total yield and yield of grade A potatoes were not significantly different between wide beds and conventional ridges at either site. At one site, yield of grade B potatoes was significantly less in the wide bed; among the three rows in the wide bed, the eastern row had significantly lower yield of grade B potatoes. Conventional ridges had a higher percent of green grade A potatoes than the wide beds in one of three trials. Under North Carolina conditions, changing production systems would be unadvisable for most growers because wide beds do not increase yield enough to justify spending the money for more seed and to change equipment.  相似文献   
100.
  • 1. The global decline of albatrosses (Diomedidae: Procellariiformes) is thought to have occurred largely as a direct result of fishery‐related mortality. Albatrosses and other large petrels interact with fisheries in several ways, including scavenging used bait and discarded offal, which may contain hooks.
  • 2. Hooks that are ingested by breeding birds are often fed to chicks which subsequently regurgitate them shortly before fledging.
  • 3. In this study a series of mathematical (cladistic, cluster and principal components) analyses are applied to a sample of 241 items of fishing gear (hook, snood and hook/snood unit) collected from seabird nest sites on Bird Island, South Georgia, and 44 reference gear items provided by four South Atlantic regional fisheries.
  • 4. The five separate analyses failed to assign most gear to a particular fishery or to identify any consistent annual trends. The homogeneous nature of the material, which was largely derived from the same manufacturers, meant that gear origin could not be determined. This suggests that hooks found at seabird colonies in this, and potentially other regions, will be of limited use in identifying offending fisheries, unless operators are obliged to deploy gear with unique marks in the future.
  • 5. Nevertheless, it is suggested that this approach should work effectively where birds interact with a range of fisheries targeting different species using variable gear. This study therefore represents an innovative approach to the characterization of lost fishing gear with potentially widespread application. Copyright © 2010 John Wiley & Sons, Ltd.
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