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Many agricultural and environmental problems are interrelated and overlapping. Several agencies, including nonprofit organizations, have developed programs to educate schoolchildren about agricultural and environmental issues; however, programs that integrate both agricultural and environmental learning, especially among middle and high school students, are limited. To facilitate agricultural and environmental learning among middle and high school students, an agricultural and environmental challenge program was developed at the University of Louisiana at Lafayette (UL Lafayette) in southwestern Louisiana. Educators conducted 4 challenge events for middle and high school students in 2002. Each event consisted of 5 stations: water quality, plant science, soil science, land management, and aquaculture. Groups of 5 to 6 students spent 25 min at each station engaged in hands-on activities and discussion. At the end of each event, appropriate tests were administered, and prizes and a scholarship to study in the College of Applied Life Sciences at UL Lafayette were awarded. Students evaluated the events at the end of the day. Teachers and students reported that the events were very interesting, informative, and educational. Hands-on activities and challenge tests enhanced student's interest, motivation, and ability to think critically about contemporary agriculture and environmental issues in the region. (Contains 1 note.)

Soil erosion is a major constraint to the sustainability of sloping-land vegetable systems. Little information is available on the effectiveness of soil conservation measures under sloping intensified vegetable systems on volcanic ash-derived soils. We hypothesized that contouring, strip cropping, and high-value contour hedgerows -- asparagus (Asparagus officinalis L.), pineapple [Ananas comosus (L.) Merr.], pigeonpea [Cajanus cajan (L.) Huth], and lemongrass [Cymbopogon flexuosus (Nees ex Steudel) J. F. Watson] -- reduce soil loss compared with the farmer's traditional practice of up-and-down cultivation on sloping lands. A field experiment tested these soil conservation technologies from 1995 to 1998 in a completely randomized block design on a 42% natural slope on a clayey, halloysitic, isothermic, Typic Kandiudox. The greatest annual soil loss (65.3 t [ha.sup.-1]) was in the up-and-down system and comparative values were 37.8 t [ha.sup.-1] for contouring, 43.7 t [ha.sup.-1] for strip cropping, and 45.4 t [ha.sup.-1] for highvalue contour hedgerows. Three rain events alone caused 47% of the total soil loss. All erosion-runoff plots showed large differences in soil properties and crop yields between the upper and the lower slope. Crop yields downslope were greater by 40% for tomato (Lycopersicon esculentum Miller), 36% for corn (Zea mays L.), and 78% for cabbage (Brassica oleracea var. capitata L.) than for upslope. In the contour hedgerow treatment, rapid terrace development changed soil properties, and crop yields for the bottom portions of bioterraces were greater by 121% for corn and 50% for tomato than yields of top portions.

Thirteen pedons representing the mountains, the upper footslopes, the lower footslopes, and the alluvial terraces of a volcanic slope in Mindanao, the Philippines were studied to understand relationships between the degree of soil development and fertility characteristics. Soils in the upper and the lower footslopes were Oxisols as were soils in the alluvial terraces, while those in the mountains were Ultisols and Inceptisols. Presence of 'amorphous components', such as allophane and imogolite, in all the pedons studied was indicated by a [is greater than] 9.4 soil pH in NaF. Halloysite, gibbsite, goethite, hematite, and cristoballite were more common minerals in the clay fraction. Surface layers of all the pedons were slightly acidic and pH increased by depth. Phosphate sorption maxima ranged from 6944 to 14208 [micro]g P [g.sub.-1], and it was closely associated with oxalate-extractable Al ([Al.sub.0]) and clay content. Inceptisols had higher phosphate sorption maxima than Oxisols. Soil samples representing the mountains showed the lowest level of both the available K and the potential buffering capacity for K ([PBC.sup.K]), while the upper footslopes had the highest level of available K. The [PBC.sup.K] values were lower for Inceptisols than for Oxisols, and they were found to be positively correlated with soil pH. There was a large difference between the cation-exchange capacity (CEC) and the effective cation-exchange capacity (ECEC), an indication of a large pH-dependent charge. Mountain soils showed lower base saturation than soils representing the upper footslopes, the lower footslopes, and the alluvial terraces.

While there are several surface water quality sampling techniques such as flow-interval, time-interval, and composite sampling, it is still a challenging task to select the appropriate sampling technique, for edge-of-field surface runoff water quality monitoring. We hypothesized that manual composite sampling gives comparable results with discrete flow-paced sampling for edge-of-field surface runoff water quality. We collected discrete flowpaced and manual composite surface runoff water samples from sugarcane (Saccharum officinarum L.) fields, pasture lands, and residential areas' from October 2002 to October 2003 and analyzed for total suspended solids (TSS), total combustible solids (TCS), five-day Biological Oxygen Demand, nitrate/nitrite-nitrogen (NO3/NO2-N), soluble reactive phosphate (SRP), total phosphorus (TP), total nitrogen (TN), and pH in the Vermilion-Teche River Basin in Southwestern Louisiana. Overall, compared to the flow-paced sampling, average five-day biological Oxygen Demand,TSS,TCS, SRP,TP, NO3/NO2-N, and TN concentrations using `composite sampling were lower by 4.3%, 8.1%, 8.2%, 9.5%, 4.1%, 36.8%, and 8.2%, respectively. 'As expected, the constituent concentrations with the flow-paced sampling and the composite sampling were significantly (α . 0.05) positively correlated. Although TSS, TCS, and SRP concentrations slightly declined with flow levels and TP, NO3/NO2-N, and TN concentrations showed a general trend of slight increase from 15,142 L (4,000 gal) to 227,125 L (60,000 gal), correlation analysis of the pooled dataset showed no significant correlation (α = 0.05) between flow level and water quality constituents in this study. Similarly, no significant differences were found on event loads ofTSS, TCS, SRP, TP, NO3/NO2-N, and TN calculated from flow-paced sampling and manual composite sampling strategies. Therefore, manual composite sampling is suggested over flow-paced sampling for edge-of-field water quality monitoring in agricultural lands and residential areas because, while producing comparable results, it reduces the cost of laboratory determination. [ABSTRACT FROM AUTHOR]