Surface-dwelling and Subterranean Invertebrate Fauna Associated with Giant Reed (Arundo donax Poaceae) in Southern California

In the southwestern United States giant reed, Arundo donax, is a nonnative invasive plant that has become widely established in moist places and forms its largest stands along riparian corridors. The most widely reported negative effects include competition with native species, increased rate of transpiration, increased potential for wildfires, and stream channel and bank alteration. However, little is known about the faunal communities associated with this plant and the potential effects on native fauna. In this study, we focused our efforts on determining the faunal composition specifically from rhizome clumps of A. donax from a site located along the Santa Margarita River in San Diego County, California. A total of 2590 individual macro-invertebrates were collected and identified, and represented 64 species from 7 classes. No sensitive species and few vertebrates were found to be in association with A. donax rhizome clumps. Four non-native invertebrate species made up 43% of the total number of captured invertebrates, and 31% of the sampled invertebrates were confirmed as native species. This study demonstrates that A. donax rhizome clumps, and the soils associated with them, provide habitat for several native macro-invertebrate species, but can be dominated by a greater abundance of non-native species

Low power digital integrated circuit design for an unusual event detector

A deep ocean capsule is proposed capable of sensing pressure, temperature, flow and direction for a study of tides and internal waves of the oceans. One of the major requirements for this capsule is the detection and recording of unusual events. To meet this need a very low power, highly reliable digital detector has been designed. COS/MOS logic with maximum use of MSI and LSI was used in the design. The detector was simulated using proposed word lengths and fixed point arithmetic which would be utilized in the ensuing hardware. The fixed point simulation was necessary to verify the problems in truncation and round-off errors and to provide necessary design criteria to ensure proper filter functioning and integral detection.http://archive.org/details/lowpowerdigitali00brunEnsign, United States NavyApproved for public release; distribution is unlimited