Land Evaluation for Maize Based on Fuzzy Set and Interpolation

The objective of this article is to apply fuzzy set and interpolation techniques for land suitability evaluation for maize in Northern Ghana. Land suitability indices were computed at point observations using the Semantic Import (SI) model, whereas spatial interpolation was carried out by block kriging. Interpolated land suitability shows a high correlation (R2 = 0.87) with observed maize yield at the village level. This indicates that land suitability is closely related to maize yield in the study area. Membership functions were further used to assess the degree of limitation of land characteristics to maize. Sixty percent of the data has membership functions ranging from 0.23 for ECEC to 1.00 for drainage. ECEC, organic C, and clay are the major constraints to maize yield. The use of the fuzzy technique is helpful for land suitability evaluation, especially in applications in which subtle differences in soil quality are of a major interest. Furthermore, the use of kriging that exploits spatial variability of data is useful in producing continuous land suitability maps and in estimating uncertainties associated with predicted land suitability indices.     

A quantitative evaluation of monitoring networks for region-specific nitrate reduction policies

Modern environmental policy implementation in many developed countries is increasingly regionally oriented. Regional governments have undertaken measures designed for the specific needs of the region but, so far, the resulting change in environmental quality has hardly been monitored. This study develops a method for the quantitative evaluation of region-specific environmental policy. Two forms of monitoring are distinguished: monitoring of performance of policy measures and monitoring of environmental quality. This study investigates two regions in the Netherlands where region-specific policy has been implemented. Performance monitoring focused on reduction of nitrate leaching to groundwater. Leaching reductions were calculated with simple models or rules of thumb. Quality monitoring focused on nitrate concentrations under grassland and other land use. An analysis of variance showed significant differences between different soil units. Stratified kriging was applied for spatial interpolation, showing within-unit variability. The current monitoring network could be improved by using a more regular type of grid.     

METABOLIC RESPONSES OF AQUATIC BACTERIAL POPULATIONS TO SELECTED INSECTICIDES1

ABSTRACT: Indigenous bacterial populations from a fresh water reservoir were treated by adding five mg/1 Sevin or Malathion to the water at 23, 28, and 33 C. The degradation of Sevin was evidenced by the increased uptake of O₂ as measured by Warburg manometry. The principal degradation product of Sevin, 1-naphthol, appeared to stimulate metabolic activity of these populations to the same extent as the parent compound. The addition of Malathion to this system appeared, on the other hand, to suppress metabolic activity to some degree. Warburg manometry was shown to be a useful, rapid method for detecting effects of insecticides on aquatic microbial populations.     

Evaluating Alternative Temporal Survey Designs for Monitoring Wetland Area and Detecting Changes Over Time in California

Evaluation of wetland extent and changes in extent is a foundation of many wetland monitoring and assessment programs. Probabilistic sampling and mapping provides a cost‐effective alternative to comprehensive mapping for large geographic areas. One unresolved challenge for probabilistic or design‐based approaches is how best to monitor both status (e.g., extent at a single point in time) and trends (e.g., changes in extent over time) within a single monitoring program. Existing wetland status and trends (S&T) monitoring programs employ fixed sampling locations; however, theoretical evaluation and limited implementation in other landscape monitoring areas suggest that alternative designs could increase statistical efficiency and overall accuracy. In particular, designs that employ both fixed and nonfixed sampling locations (alternately termed permanent and temporary samples), termed sampling with partial replacement (SPR), are considered to efficiently and effectively balance monitoring current status with detection of trends. This study utilized simulated sampling to assess the performance of fixed sampling locations, SPR, and strictly nonfixed designs for monitoring wetland S&T over time. Modeled changes in wetland density over time were used as inputs for sampling simulations. In contrast to previous evaluations of SPR, the results of this study support the use of a fixed sampling design and show that SPR may underestimate both S&T.     

Homesickness,health and efficiency in first year students

The investigation is concerned with the reported incidence and frequency of homesickness following an environmental transition to university in a group of 101 first year university students. Definitions provided by students indicated that homesickness is a collective term for a number of cognitive and emotional/motivational experiences primarily associated with missing home and wanting to visit it. 60% reported homesickness. Geographical distance of the move and relative lack of satisfaction with features of the psychosocial and physical environment in the new place were found to be associated with homesickness reporting. Personality and circumstantial factors such as decisional control over the move and cognitive failure levels were also associated with homesickness reporting. A two-stage risk model is proposed in which an environmental relocation is a necessary but not a sufficient condition for homesickness; features of the new place combine with personality factors to precipitate the experience.     

Trace Metals and Organochlorine Pesticide and PCB Residues in Mussels from England and Wales, 1978

As part of its work on marine environmental protection the Ministry of Agriculture, Fisheries and Food's, Fisheries Laboratory at Burnham-on-Crouch, undertook a mussel survey in England and Wales in 1978. Trace metal, organochlorine pesticide and PCB residue concentrations were determined. The survey comprised about 80 samples covering the whole of England and Wales.

The results of the survey showed that in general the contaminant concentrations reflected the expected environmental distributions of the compounds of interest. Samples from areas with significant anthropogenic inputs such as industrial estuaries generally contained the highest concentrations and samples from areas influenced mainly by natural sources usually contained much lower contaminant concentrations, although there were some notable exceptions. The survey indicates the usefulness of a mussel watch approach to monitoring in England and Wales and the suggestion is made that if used on a local more intensive scale the technique should be able to identify in greater detail the likely sources of pollution.     

The transition from home to boarding school: a diary-style analysis of the problems and worries of boarding school pupils

The investigation concerns the impact of the new school environment on a group of 50 male and female children aged 11–16 years, who leave home to reside temporarily at boarding school, in terms of the characteristics of problems and worries reported and the incidence of spontaneous reports of homesickness. More problems relating to the school than to the home environment were reported but proportionally more worry units were reported associated with home problems for both males and females. There was no sex differences in this respect. The reported level of spontaneously reported homesickness was 16% and there were no sex differences. Factors such as age, geographical distance of move and decision to go away to school were not influential in determining the level of reported problems or incidence of spontaneous reports of homesickness. A relationship was found with level of problems reported and recent life history but the result proved difficult to interpret.     

A COMPARISON OF PHOSPHORUS AND WATER CONTRIBUTIONS BY SNOWFALL AND RAIN IN NORTHEAST OHIO1

ABSTRACT A record snowfall of 55.8 centimeters occurred on December 1 and 2, 1974 in Portage County, Ohio. An early winter thaw melted the greater part of the snow by December 22, 1974, and a two-day rain fell from December 23 to December 25. These weather events provided an opportunity to compare snowmelt and rainfall contribution to runoff and phosphorus loading to the Twin Lakes Watershed. Phosphorus concentrations of the snow and rain were determined. Six lake inflows and two lake outflows were measured daily for volume and phosphorus concentration. The snow added 217,000 cubic meters of water and 2.2 kilograms of total phosphorus to the watershed. The rain added 74,000 cubic meters of water and 1.6 kilograms of total phosphorus. Total water discharge from the watershed during December was 244,537 cubic meters and total phosphorus output was 20.3 kilograms. The snow provided 49.9% of the discharge and 8% of the phosphorus whereas the rainfall contributed 28% of the discharge and 6% of the phosphorus. These results indicate that while snow is a significant source of water, it is not a large source of phosphorus. The greatest contribution of phosphorus comes from fine sediment carried by storm runoff.     

Real-world vehicle emissions: A summary of the 15th coordinating research council on-road vehicle emissions workshop

The Coordinating Research Council held its 15th workshop in April 2005, with nearly 90 presentations describing the most recent mobile source-related emissions research. In this paper, the authors summarize the presentations from researchers who are engaged in improving our understanding of the contribution of mobile sources to air quality. Participants in the workshop discussed emission models and emission inventories, results from gas- and particle-phase emissions studies from spark-ignition and diesel-powered vehicles (with an emphasis in this workshop on particle emissions), effects of fuels on emissions, evaluation of in-use emissions control programs, and efforts to improve our capabilities in performing on-board emissions measurements, as well as topics for future research.