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701.
Robert N. Magai W. L. Decker Armon J. Keaster 《International journal of biometeorology》1997,40(3):128-134
The European corn borer is one of the most damaging insect pests to maize in the United States. Different methods exist for
the estimation of time of damage to corn by first generation European corn borer. The most commonly used method is the linear
thermal constant concept of phenology which by convention calculates cumulative thermal units from January 1 or another arbitrary
date. Linear and nonlinear models based on the thermal units concept developed were to predict and simulate postdiapause development
of the European corn borer and subsequent infestation of the maize crop using early spring temperatures (May 1–15) in central
Missouri. The developmental rates of European corn borer were obtained from growth chamber investigations that simulated those
temperatures, the operational temperatures being selected from a compilation of archival meteorological data from 1948 to
1989. The linear and polynomial regression models were developed to predict phenological stages of the European corn borer
using thermal units as developmental rates. The models were compared against each other to determine the better predictor
of estimation values: each explained 94 and 98% of the variation in developmental stages, respectively. In addition, the models
were tested against independent field data and both models gave good predictions of developmental stages, indicating that
either model would be a good predictor.
Received: 9 September 1994 / Revised: 28 December 1995 / Accepted: 8 August 1996 相似文献
702.
703.
Lorraine N. Fleming Harrison N. Abinteh Hilary I. Inyang 《Soil & Sediment Contamination》1996,5(1):53-59
The leachability of metals from fly ash produced by a coal‐fired electric plant and a municipal waste incinerator under acidic conditions was experimentally investigated. The results of these column‐leaching experiments show that a decrease in the pH of the leachant favors the extraction of metal ions from solid particles of both coal combustion fly ash and municipal waste incinerator fly ash. The significant increase in the extraction of cadmium, chromium, zinc, lead, mercury, and silver ions from the ash is attributed to the instability of the mineral phases that contain these metals under acidic conditions. 相似文献
704.