Spatial distribution of introduced brook trout Salvelinus fontinalis (Salmonidae) within alpine lakes: evidences from a fish eradication campaign

Brook trout Salvelinus fontinalis have been used worldwide to stock fishless alpine lakes, negatively affecting native biota. Understanding its spatial ecology in invaded ecosystems can provide information to interpret and contrast its ecological impact. We opportunistically used capture points of brook trout gillnetted during an eradication campaign to assess the distribution patterns of four unexploited populations inhabiting high-altitude lakes. The main eradication method implies the use of many gillnets with several mesh sizes, which are selective for different fish sizes. For each lake we drew six capture maps associated with as many different mesh sizes, and we tested whether the distance from the coastline (which in alpine lakes is a reliable proxy of the most important spatial gradients, e.g. depth, temperature, prey availability, lighting conditions) influences the proportion of captured fish belonging to different size classes and the number of fish captured by the nets with different mesh sizes. To interpret the results, we also provide a cartographic description of the lakes’ bathymetry and littoral microhabitats. We found (1) a negative relationship between brook trout distribution and the distance from the coastline in all of the size classes, lakes and mesh sizes; (2) that large brook trout can thrive in the lakes’ center, while small ones are limited to the littoral areas; and (3) that the distance from the coastline alone cannot explain all the differences in the catch densities in different parts of the lakes. As in their native range, introduced brook trout populations also have littoral habits. Microhabitats, prey availability and distance from the spawning ground are other likely factors determining the distribution patterns of brook trout populations introduced in alpine lakes. The obtained results also provide useful information on how to plan new eradication campaigns

Valuasi Sumberdaya Air (Studi Kasus Kawasan Mata Air Tataneyan di Kelurahan Kinilow I, Kecamatan Tomohon Utara, Kota Tomohon)

This study aims to determine how how big the valuations of water in the spring Tataneyan located in the Village Kinilow I, District of North Tomohon, Tomohon, by using the concept of economic valuation to calculate the value of the utilization of water resources directly or indirectly. This study was conducted from October to December 2016, using primary and secondary data with sampling technique simple random sampling method and the respondents as many as 30 people. Analysis of the data used is quantitative analysis to identify the value of the value of benefits in the area of water resources in the waters Tataneyan value direct use for domestic households and public bath are also value the presence of fish breeding and agricultural irrigation water spinach. The results showed that the area of the springs Tataneyan have a total economic benefit value of Rp. 1.586.715.372/year. By calculating the average value of the obtained surplus WTP consumers showed the overall consumer receives more benefits than the actual price that is able to pay in exploiting springs Tataneyan. The total value of economic benefits can be used as a reference for local communities in the utilization and management of water in the spring Tataneyan

SuperCDMS Cold Hardware Design

We discuss the current design of the cold hardware and cold electronics to be used in the upcoming SuperCDMS Soudan deployment. Engineering challenges associated with such concerns as thermal isolation, microphonics, radiopurity, and power dissipation are discussed, along with identifying the design changes necessary for SuperCDMS SNOLAB. The Cryogenic Dark Matter Search (CDMS) employs ultrapure 1-inch thick, 3-inch diameter germanium crystals operating below 50 mK in a dilution cryostat. These detectors give an ionization and phonon signal, which gives us rejection capabilities regarding background events versus dark matter signals.United States. Dept. of Energy (Grant DEAC02-76SF00515)United States. Dept. of Energy (Contract DC-AC02-07CH11359)National Science Foundation (U.S.) (Awards 0705052, 0902182, 1004714 and 0802575