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Urban areas have been conceived of as monolithic heat islands because traditional ground observation techniques do not lend themselves to more specific analyses. Observations of urban energy-exchange obtained from calibrated electro-optical scanners combined with energy budget simulation techniques provide tools to relate the urban land use mosaic to the heat island phenomenon. Maps of surface energy-related phenomena were made from airborne scanner outputs for selected flightpaths across the city of Baltimore, Maryland. Conditions for the flight time were simulated according to the various types of land use using an energy budget simulation model which lends itself to extrapolation of simulated grid-point conditions into a map form. Maps made by simulation compare sufficiently well with those made by aerial observation to encourage further refinement of the simulation approach. key environmental challenge that faces A man is the production of a more hospitable climate in urban areas while minimizing manmade energy inputs. This paper uses surrogate methods to develop some fundamental relationships between surface properties and urban microclimates in order to provide environmental information for national land use planning. Energy relationships of various urban land uses are investigated using measurements Modeling the Effect of Land Use on the Urban Temperature Field, unpublished doctoral dissertation, FIG. 4. A simulated distribution of radiation temperatures (top) compared with an "ob-served" or scanner-derived map (bottom). Both maps have the same scale along the flightline but only the simulated map is planimztric. The observed map is compressed transverse to the flightline because of the rolloff of straight scanline imagery due to the nonlinearities of the tangent function and the distortion of the line printer.

A pilot-scale land treatment unit (LTU) was constructed at the former Guadalupe oil production field with the purpose of investigating the effect of co-substrate addition on the bacterial community and the resulting rate and extent of total petroleum hydrocarbon (TPH) degradation. The TPH was a weathered mid-cut distillate (C10-C32) excavated from the subsurface and stockpiled before treatment. A control cell (Cell 1) in the LTU was amended with nitrogen and phosphorus while the experimental cell (Cell 2) was amended with additional complex co-substrate-corn steep liquor. During the pilot LTU operation, measurements were taken of TPH, nutrients, moisture, aerobic heterotrophic bacteria (AHB), and diesel oxidizing bacteria (DOB). The bacterial community was also assayed using community-level physiology profiles (CLPP) and 16S rDNA terminal restriction fragment (TRF) analysis. TPH degradation in both cells was characterized by a rapid phase of degradation that lasted for the first three weeks, followed by a slower degradation phase that continued through the remainder of the project. The initial rate of TPH-degradation inCell 1 (-0.021 day -1 ) was slower than in Cell 2 (-0.035 day -1 ). During the slower phase, degradation rates in both cells were similar (-0.0026 and -0.0024 INTRODUCTIONBioremediation is the conversion of undesirable compounds (pollutants) into preferable end products using biological processes.This process is well documented for petroleum hydrocarbons (Abed et al., 2002;Admon et al., 2001;Al-Awadhi et al., 1996 Bartha, 1972;Huesemann & Truex, 1996;Juck et al., 2000;Mishra et al., 2001;Morgan & Watkinson, 1990;Venosa et al., 1996); however, chemical, physical, and biological factors can affect the rate and extent of hydrocarbon degradation.These factors include specific hydrocarbon compound structures, their bioavailability, and the nature of the soil or matrix in which the petroleum resides. In addition, environmental conditions such as the type and quantity of nutrients, moisture, soil pH, and the availability of suitable electron acceptors are important factors affecting the degradation rate. Despite these caveats, bioremediation is commonly used to remediate petroleum-contaminated soils. The addition of nutrients, electron acceptors, and moisture has long been advocated to optimize biodegradation capacity, especially in highly engineered systems such as land treatment units (Huesemann & Truex, 1996;MacNaughton, 1999;Mishra et al., 2001;Morgan & Watkinson, 1990).The addition of a co-substrate such as methane is commonly used during bioremediation of chlorinated compounds such as trichloroethane (Watanabe, 2001). In contrast, co-substrate addition has not been investigated for the enhancement of petroleum degradation. In part, this is because total petroleum hydrocarbons (TPH) are widely considered to be a readily degradable mixture of compounds. However, petroleum is a very complex mixture, and there are many compounds in TPH that may not be readily degraded. In particular, weathered pe...

Abstract--Dioctahedral aluminum smectites from bentonite deposits in Argentina, Brazil, Czechoslovakia and Japan represent, according to the MgO content of the bulk samples, intermediate members in the montmorillonite-beidellite series. The smectite particles in these samples occur in a variety of forms such as; (a) laths and diamond-shaped units with a well developed crystal habit, (b) loosely folded aggregates with an irregular morphology and (c) flat and compact lameltae with well developed I0011 forms but with complete lack of {hk0] forms. Such lamellae have been described in two groups: the thin ones (10-50 A) and the thicker ones. Thin lamellae may give SAD spot patterns with a nonhexagonal symmetry. Lamellae having thicknesses greater than 50 A resemble a single crystal but their SAD patterns indicate that they do not have a three-dimensional periodicity.The question arises whether the morphologically different particles in a sample belong to the same intermediate phase or if they represent different members in the montmorillonite-beidellite series coexisting in the same sample.

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