MORAL EKONOMI PETANI:Pergolakan dan Subsistensi di ASIA TENGGARA

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A Fisheries Evaluation of the Dryden Fish Screening Facility : Annual Report 1994.

Effectivness was evaluated of the Dryden Fish Screening Facility in the Wenatchee Reclamation District Canal near Dryden in north central Washington State. In situ tests were conducted by releasing groups of hatchery reared salmonids of different ages and sizes. Spring chinook salmon smolts (110-165 mm) were not injured or descaled in passing through the canal forebay. Smolts were not delayed as they migrated in the canal. Most fish released at the canal headworks exited the screening facility in 99% of the test fish captured in the fish bypass in <24 h. Steelhead subyearlings 65-125 mm were not injured or descaled in traveling through the bypass flume and fish return pipe. Average time for steelhead subyearlings to travel through thebypass structure was 70 seconds. Small rainbow trout fry 23-27mm could pass through the 0.125-in. profile bar screen openings and were entrained in the irrigation canal; about 38% was lost to the canal within 48 h of release. Some fry stayed in the forebay and did not migrate during the tests. Wild chinook fry 36-42mm were also entrained. Estimated 34% of emergent wild chinook salmon fry passed through the profile bar screens and were entrained in the canal. Approach velocity at the Dryden screens was {ge}0.4 ft/s; low velocities through the first two screen panels indicated that vertical louvers installed behind each screen panel to balance flow were not totally effective

The Reduviidae (Hemiptera: Heteroptera) of Alabama, with a morphological key to species

Clem, C.Scott, Swanson, Daniel R., Ray, Charles H. (2019): The Reduviidae (Hemiptera: Heteroptera) of Alabama, with a morphological key to species. Zootaxa 4688 (2): 151-198, DOI: https://doi.org/10.11646/zootaxa.4688.2.

A Fisheries Evaluation of the Richland and Wapato Canal Fish Screening Facilities, Spring 1987 : Annual Report.

We evaluated the effectiveness of new fish screening facilities at the Richland and Wapato canals in south-central Washington State. The screen integrity tests at the Richland Screens indicated that 100% of fall chinook salmon fry (Oncorhynchus tshawytscha) released in front of the screens were prevented from entering the canal behind the screens. Our estimate is based on a 61% catch efficiency for control fish planted behind the screens. At the Wapato Canal, we estimated that between 3% and 4% of the test fish were either impinged on the screen surface and passed over the screens or passed through faulty screen seals. Our estimate is based over the screens or passed through faulty screen seals. Our estimate is based on a greater than 90% capture of control fish released in front of the screens. At the Wapato Screens, we estimated that 0.8% of steelhead smolts (Salmo gairdneri) and 1.4% of spring chinook salmon smolts released during low canal flow tests wee descaled. During full canal flow tests, 1.6% of the steelhead and 3.1% of the spring chinook salmon released were descaled. The fish return pipe at the Wapato Canal was tested: the estimate of descaled test fish wa not different from the estimate of descaled control fish. The time required for fish to exit from the Wapato Screen forebay varied with species and with canal flow. During low canal flows, 43.2% of steelhead and 61.6% of spring chinook salmon smolts released at the trash racks were captured in the fish return within 96 hr. 11 refs., 11 figs., 10 tabs