<p>The solubility of heavy metal (trace metal) contaminants in soils depends on metal concentration, chemical speciation, and conditions such as pH, redox potential, and ionic strength of the soil solution. The objective of this study was to determine the dissolution (potential mobilization) of metal contaminants in response to induced changes in pH and redox potential in soils surrounding abandoned incinerators at two outlying US Marine Corps air fields: MCALF-Bogue and MCOLF-Atlantic. Concentrations of heavy metals measured in 17 soil samples ranged from 1 to 101 mg Zn/kg, 2 to 45 mg Cu/kg,3 to 105 mg Pb/kg, 0.3 to 12 mg Cr/kg, <0.01 to 0.6 mg Cd/kg, <0.1 to 0.6 mg Se/kg, 0. 5 to 81 mg Ba/kg, and 5. Decreasing redox potential (Eh) if soil samples from at the MCALF-Bogue site to 250 mV caused minimal dissolution of Cu, Zn, Pb, and Cr. <P>

Vast areas of abandoned or sub-marginal land exist. In Quebec alone it has been estimated that there are about 1,400,000 acres of abandoned farmland (32). Some of this land is being turned into tree farms and more of it could be so utilized if some problems could be overcome. The chief difficulties existing are mainly those of uneven topography, poor drainage and low fertility status of the soil. This latter problem could be possibly the easiest difficulty to overcome provided adequate knowledge existed of the effects of fertilization on reforested areas. To assess relative fertility levels of soils for purposes of reforestation methods of soils analysis as well as plant analysis may be useful. These must be developed in conjunction with fertilizer application experiments either in the field or in the greenhouse under a controlled environment.

The advent of radioactive isotopes as tracers in fertilizers, led to a new concept of determining availability of soil nutrients to the plant (Fried and Dean, 1952; Larson, 1952). [...]

Inadequate drainage is a challenging problem in both humid and arid regions of the world. In arid regions water logging is the basic cause of salinity and alkalinity, and they go hand in hand. One of these conditions usually indicates the presence of the other. [...]

In a preliminary study, different amounts of iron and aluminum phosphates were added to Bf and Ah horizon materials, and potassium phosphate was added to a mixed L-F-H horizon material. The soil materials were then incubated for 16 days and analysed for extractable Al, Fe and P (Olsen's method). Results after incubation showed that the Bf and Ah horizon material had more extractable Fe and Al than the L-F-H material. Extractable P suggested a P deficiency in Bf soil material and a relatively high level of available P in L-F-H material. Addition of large amounts of iron and aluminum phosphates to the Bf and Ah material yielded only slight increases in extractable P. However, the amounts of extract-able P indicated that the phosphate forms added to these soil materials could remain partially extractable for some time and it was inferred that they resembled native soil phosphates rather than fertilizer phosphates. Next, the availability of phosphorus to two conifer species (Pinus patula and Cupressus lusitanica) was tested for the same three forest soil materials. Different amounts of phosphorus were added to these materials, as before, and seedlings of the two plant species were grown for 178 days. Phosphorus uptake by the seedlings was measured and correlated with the concentration of soil phosphorus extracted by five methods (Bray P-l, modified Bray P-l, Olsen, Truog and Mehlich), in order to identify the most suitable extraction method to serve as an index of soil phosphorus availability to the tree seedlings. Seedling growth (height, diameter, and biomass) was least for seedlings grown in Bf and greatest for those grown in L-F-H materials. Seedlings grown in Bf soil material showed, generally, greater biomass for roots than for foliage or stem, but those grown in the least P-deficient (L-F-H)material had greater biomass for foliage than stem or roots. Analysis of P uptake by seedlings indicated slightly higher P concentration in roots than in stem or foliage. Total P uptake was least from Bf and highest from L-F-H materials. Phosphates added to mineral soil gave a substantial relative increase in total P uptake, especially for Bf materials. However, for L-F-H material, added phosphates caused increases in uptake which were mostly large in absolute value, but small relative to uptake from unamended soil. Cupressus lusitanica seedlings accumulated more phosphorus than Pinus patula seedlings with the low P levels, while the opposite was usually the case with the high P levels. Extractable P after seedling growth was lowest in Bf and highest in L-F-H materials and it increased with increase in the amount of phosphates added. 01 sen's method extracted more P from the three soil materials than any of the other extraction methods. There were slight, inconsistent differences in the amounts of P extracted by the Bray P-l and modified Bray P-l methods. While phosphorus concentration in soil extracted by the five methods from the three soil materials where Pinus patula seedlings were grown correlated with each other, P extracted by Mehlich method from the Ah soil material failed to correlate with the other methods except the Olsen method. For pine, concentration of P extracted by all the methods from the three soil materials yielded significant (P≤0.05 and P≤0.10, respectively) correlation with P uptake from the P-deficient Bf, but failed to yield significant (P≤0.10) correlation with P uptake from Ah material. The Olsen, Truog and Bray P-l methods yielded very significant (P≤0.01) correlation with P uptake by cypress from Ah material. Correlation analysis of foliar P concentration with extractable P concentration in soil showed significant (P≤0.05) correlation for P i n us patula. with all methods. All but the Truog method yielded significance at P≤0.01. For Cupressus lusitanica, correlations were better with Bf than with Ah and L-F-H materials, and only the Olsen method yielded significance (P≤0.10) with all three materials. Overall, considering all soil materials and both species, the Olsen method yielded the most satisfactory relationships with P uptake by the seedlings and with foliar P concentration. / Land and Food Systems, Faculty of / Graduate

Soil moisture and nitrogen are often the primary controlling factors of crop production . Production functions are valuable in describing crop responses to such controlling factors. Such functions are al so needed for determining the economic reliability of crop production. Soil moisture and nitrogen fertilizer were maintained at various levels to determine the response of field corn to these controlling factors. A conventional split plot design, a continuous function experimental design, and a confined barrel plot design were used to obtain data for determining production functions. The complete factorial, conventional split plot data was successfully used to generate reliable production functions in two locations. The multiple correlation coefficient was approximately 0. 68. The continuous function design consisted of a large number of treatment combinations with only small sequential increments in treatment levels , from plot to plot. This made it possible to eliminate border rows and use a much smaller plot size. The design was tested in two locations, using 10 soil moisture levels and 22 nitrogen fertilizer levels. The multiple correlation coefficients were about 0.33 and 0.49. Using this design, it was necessary to replicate entire blocks. The production functions from the conventional split plot design and continuous variable plot design compared favorably within locations, but not between locations. Production functions were also determined for relative yields and treatments . The inputs were expressed as fractions relative to both the maximum and optimum levels. The relative production functions were similar for both locations. The production functions were tested for transferability by making adjustments in the input data to account for site specific controlling factors. No definite conclusions were possible although the results suggest that transferability is possible. Several reduced field designs were also tested using the data obtained. Three different incomplete factorial, split plot designs appear to be suitable for generating production functions. Grouping of the continuous function plots to as few as four soil moisture levels by four fertilizer levels also gave reliable production functions. Several suggestions regarding the use of reduced field designs are presented along with suggested future research needs in this area . The data indicate that the continuous variable design is quite useful for determining production function s. The barrel plots consisted of field corn grown under various treatment combinations on undisturbed soil cores. The data obtained from these barrel plots (210 liters) were too variable to generate a reliable production function.

The study was designed to test the genetic theory of soil development of two soils derived from different geological material , but developed under conditions of similar climate, topography, biological activity, and age. An attempt was made to relate the soils characteristics to their present classification. Parleys and Mendon series which developed from Bonneville and Salt Lake Formation, respectively, were selected for that purpose. Along the east side of Cache valley , two pedons representing each of the studied series were selected to have similar soil formers except for their parent material. Evidently , these studied soils have been developed (rom different heterogenous sediments. Mendon soils have been developed from Salt Lake Formation to at least 51 cm depth, whereas, the solum horizons are attributed to the Bonneville Formation. The Parleys soil seems to be mainly developed from Bonneville formation. But the upper solum horizons are probably interlayered with fine deposits of Holocene age. Those soils which derived from different geological deposits show a high degree of similarity between them. Heterogeneity and the nature of the soil parent material, and similarity of their climatic and developmental conditions are believed to be the major causes to inhibit many genetic variables between them. In northern Utah, the Hendon soils are classified as Calcic Pachic Argixerolls, at the subgroup level. This study has shown that most of the Mendon pedons do not have a Pachic epipedon. Therefore, these studied soils could be grouped together in one subgroup. The result is Calcic Argixerolls in ftne-silty, mixed, mesic family. Re-examining Mendon series in Cache valley and reclassifying them on the basis of Pachic epipedon would be an interesting subject for further study.

No description available.

No description available.

No description available.