HYDROLOGIC EFFECTS FROM CHANGES IN GROUND WATER PUMPAGE1

ABSTRACT: Simulation of a large stream-aquifer system in Nebraska has been accomplished for the period from 1975 to 2020 to determine effects of controls on ground water pumpage. Three scenarios tested consisted of average annual withdrawals of 15.2 ac-in/ac (FUTURE 1), 14.8 ac-in/ac (FUTURE 2), and 9.8 ac-in/ac (FUTURE 3). The highest quantity represents the historical tendency; while the 14.8 in. figure represents a slight reduction and also represents an equalization of irrigation application efficiencies throughout the area. The lowest figure represents a substantial increase in application efficiency. Comparisons between simulated ground water elevations indicate maximum savings of FUTURE 2 over FUTURE 1 of less than 8 ft. FUTURE 3 ft. FUTURE 3 levels are projected to be a maximum of approximately 13 ft. higher than FUTURE 1's. The relatively small savings from reductions in pumpage result primarily from recirculation effects. Differences between ground water contributions to stream flow are small for all scenarios. These contributions decrease with time and increasing pumpage amounts. Base flow rates at the end of the simulation are approximately 25 percent of those at the beginning.     

OPTIMAL RESERVOIR MANAGEMENT AND CROP PLANNING UNDER DETERMINISTIC AND STOCHASTIC INFLOWS1

ABSTRACT: This study analyzes planning under deterministic and stochastic inflows for the Mayurakshi project in India. Models are developed to indicate the optimal storage of reservoir water, the transfer of water to the producing regions, and the spillage of water from the reservoir, if needed. A deterministic programming model was first formulated to represent the existing situation. A chance-constrained model then was constructed to evaluate potential violations of the deterministic model. Both models were quantified for the command area. Data were collected from surveys of the area and from government agencies. Both the deterministic and change-constrained models suggest a more intensive cropping program in the region. Both emphasize more dependence on rabi and less on kharif crops. The chance-constrained especially suggests use of more water in the rabi season. Important chances in cropping programs and labor use take place under the chance-constrained model.     

A Spatial equilibrium perspective for planning the production of electrical energy

A spatial and temporal equilibrium model of production, consumption, prices, and transmission is constructed to determine the efficient pricing and allocation of electrical energy in the United States. Regional coordination is technically feasible and economically attractive. It also maximizes environmental efficiencies. The duplication of electrical generation and transmission facilities yields a misallocation of resources.The utilities put forth specific arguments against coordinated operations. Yet in a fully integrated power system, each region would be expected to maximize the benefits of time diversity by purchasing from outside the region in lieu of the expansion of regional capacity. The Federal Energy Regulatory Commission has not yet made a serious move to encourage regional coordination and planning, but the Commission has the authority to promote such operations if it chooses to do so.The author is an economist with the Department of Energy. The views expressed are those of the author and do not necessarily represent the policies of the Department of Energy or the views of other staff members.     

焦化苯初馏份蒸馏釜发生爆炸的原因探讨

通过对某企业的一起典型爆炸事故案例进行分析,找出其产生的原因,提出了预防措施。     

Queen control of egg fertilization in the honey bee

The study investigated the precision with which honey bee queens can control the fertilization of the eggs they lay. Because males and workers are reared in different-sized cells, the honey bee is one of the few Hymenoptera in which it is possible for the experimenter to know which type of egg a queen “intends” to lay. Eggs were collected from both worker and drone (male) cells from four honey bee colonies. Ploidy of the embryo was determined using polymorphic DNA microsatellites. All 169 eggs taken from worker cells were heterozygous at at least one microsatellite locus showing that the egg was fertilized. All 129 eggs taken from drone cells gave a single band at the B124 locus, strongly suggesting haploidy. These data show that honey bee queens have great, and quite possibly complete, ability to control the fertilization of the eggs they lay. Data from the literature suggest that in two species of parasitoid Hymenoptera (Copidosoma floridanum, Colpoclypeus florus) females have great, but not complete, ability to control fertilization. Received: 23 December 1997 / Accepted after revision: 17 May 1998     

Energy use and allocation in the Florida harvester ant, Pogonomyrmex badius: are stored seeds a buffer?

Limitation of a necessary resource can affect an organism’s investment into growth and reproduction. Pogonomyrmex harvester ants store vast quantities of seeds in their nests that are thought to buffer the ants when external resources are not available. This research uses externally controlled food availability to examine how resource shortage affects colony investment, resource use, and resource distribution within the nest. Colonies were either starved or supplemented with resources for 2 months, beginning at the onset of reproductive investment and ending immediately before nuptial flights. Fed colonies invested more in overall production, proportionally more in reproduction relative to growth and in female reproductives relative to males. Stored seeds in starved colonies did not buffer production in this study. However, worker fat reserves were depleted in starved colonies, indicating that fat reserves fuel the spring bout of production. In starved colonies, worker fat reserves were depleted evenly throughout the nest, distributing the burden of starvation on all workers regardless of caste and age. A reallocation of diploid eggs into female workers rather than reproductives best explains the observed change in sex ratio investment between treatments. The redistribution of resources into growth relative to reproduction in starved colonies is consistent with life history theory for long-lived organisms, switching from current to future reproduction when resources are scarce.