Search results for "Lake"
showing 10 items of 369 documents
Interesujące gatunki chrząszczy (Coleoptera) z Puszczy Piskiej
2022
W lipcu 2002 roku huragan zniszczył drzewostany na znacznym obszarze Puszczy Piskiej. Część uszkodzonego lasu – 475 ha – pozostawiono bez ingerencji (Las Ochronny „Szast”) – do naturalnej sukcesji. W latach 2005–2021 badano chrząszcze na wybranych powierzchniach pohuraganowych i kontrolnych. Do odłowów stosowano różne typy pułapek (IBL-2bis, Netocia, Moerickego). Uzupełnieniem były odłowy Coleoptera metodą „na upatrzonego” oraz analizy potencjalnego materiału lęgowego chrząszczy. W sumie w trakcie badań wykazano 1000 gatunków Coleoptera. W pracy przedstawiono dane taksonów: rzadkich, reliktów puszczańskich i wymienionych w Czerwonej Liście zwierząt ginących i zagrożonych w Polsce. Ogółem 32…
Tracking Formation of a Lava Lake From Ground and Space: Masaya Volcano (Nicaragua), 2014-2017
2018
A vigorously degassing lava lake appeared inside the Santiago pit crater of Masaya volcano (Nicaragua) in December 2015, after years of degassing with no (or minor) incandescence. Here we present an unprecedented-long (3 years) and continuous volcanic gas record that instrumentally characterizes the (re)activation of the lava lake. Our results show that, before appearance of the lake, the volcanic gas plume composition became unusually CO 2 rich, as testified by high CO 2 /SO 2 ratios (mean: 12.2 ± 6.3) and low H 2 O/CO 2 ratios (mean: 2.3 ± 1.3). The volcanic CO 2 flux also peaked in November 2015 (mean: 81.3 ± 40.6 kg/s; maximum: 247 kg/s). Using results of magma degassing models and budg…
2017
Abstract. During free fall in clouds, ice hydrometeors such as snowflakes and ice particles grow effectively by riming, i.e., the accretion of supercooled droplets. Volatile atmospheric trace constituents dissolved in the supercooled droplets may remain in ice during freezing or may be released back to the gas phase. This process is quantified by retention coefficients. Once in the ice phase the trace constituents may be vertically redistributed by scavenging and subsequent precipitation or by evaporation of these ice hydrometeors at high altitudes. Retention coefficients of the most dominant carboxylic acids and aldehydes found in cloud water were investigated in the Mainz vertical wind tu…
Insights Into the Mechanisms of Phreatic Eruptions From Continuous High Frequency Volcanic Gas Monitoring: Rincón de la Vieja Volcano, Costa Rica
2019
OVSICORI Understanding the trigger mechanisms of phreatic eruptions is key to mitigating the effects of these hazardous but poorly forecastable volcanic events. It has recently been established that high-rate volcanic gas observations are potentially very suitable to identifying the source processes driving phreatic eruptions, and to eventually detecting precursory changes prior to individual phreatic blasts. In February-May 2017, we deployed a Multi-GAS instrument to continuously monitor gas concentrations in the crater lake plume of Rincón de la Vieja, a remote and poorly monitored active volcano in Costa Rica, site of frequent phreatic/phreatomagmatic eruptions. Forty-two phreatic/phreat…
Drowned Landscapes: The Rediscovered Archaeological Heritage of the Mosul Dam Reservoir
2023
Like natural catastrophes or armed conflicts, resource extraction projects herald the alteration or destruction of natural and cultural landscapes alike. Dam construction is a major threat to cultural heritage in Western Asian archaeology. One event may result in obliterating hundreds of sites, most of which never reappear or do so only sporadically following cyclical water fluctuation. Destruction of sites remains ongoing, necessitating constant assessment of damage and the establishment of strategies of documentation and maintenance. This paper proposes a new paradigm for future safeguarding and, more widely, a new tool for managing contiguous terrestrial and lacustrine cultural zones. It…
Warmer climates boost cyanobacterial dominance in shallow lakes
2011
Dominance by cyanobacteria hampers human use of lakes and reservoirs worldwide. Previous studies indicate that excessive nutrient loading and warmer conditions promote dominance by cyanobacteria, but evidence from global scale field data has so far been scarce. Our analysis, based on a study of 143 lakes along a latitudinal transect ranging from subarctic Europe to southern South America, shows that although warmer climates do not result in higher overall phytoplankton biomass, the percentage of the total phytoplankton biovolume attributable to cyanobacteria increases steeply with temperature. Our results also reveal that the percent cyanobacteria is greater in lakes with high rates of ligh…
Elimination of cyanobacteria and microcystins in irrigation water—effects of hydrogen peroxide treatment
2020
AbstractCyanobacterial blooms pose a risk to wild and domestic animals as well as humans due to the toxins they may produce. Humans may be subjected to cyanobacterial toxins through many routes, e.g., by consuming contaminated drinking water, fish, and crop plants or through recreational activities. In earlier studies, cyanobacterial cells have been shown to accumulate on leafy plants after spray irrigation with cyanobacteria-containing water, and microcystin (MC) has been detected in the plant root system after irrigation with MC-containing water. This paper reports a series of experiments where lysis of cyanobacteria in abstracted lake water was induced by the use of hydrogen peroxide and…
New enveloped dsRNA phage from freshwater habitat.
2015
Cystoviridae is a family of bacteriophages with a tri-segmented dsRNA genome enclosed in a tri-layered virion structure. Here, we present a new putative member of the Cystoviridae family, bacteriophage ϕNN. ϕNN was isolated from a Finnish lake in contrast to the previously identified cystoviruses, which originate from various legume samples collected in the USA. The nucleotide sequence of the virus reveals a strong genetic similarity (~80 % for the L-segments, ~55 % for the M-segments and ~84 % for the S-segments) to Pseudomonas phage ϕ6, the type member of the virus family. However, the relationship between ϕNN and other cystoviruses is more distant. In general, proteins located in the int…
Top consumer abundance influences lake methane efflux
2015
Lakes are important habitats for biogeochemical cycling of carbon. The organization and structure of aquatic communities influences the biogeochemical interactions between lakes and the atmosphere. Understanding how trophic structure regulates ecosystem functions and influences greenhouse gas efflux from lakes is critical to understanding global carbon cycling and climate change. With a whole-lake experiment in which a previously fishless lake was divided into two treatment basins where fish abundance was manipulated, we show how a trophic cascade from fish to microbes affects methane efflux to the atmosphere. Here, fish exert high grazing pressure and remove nearly all zooplankton. This re…
Functional and genomic diversity of methylotrophic Rhodocyclaceae: description of Methyloversatilis discipulorum sp. nov.
2015
Three strains of methylotrophic Rhodocyclaceae (FAM1T, RZ18-153 and RZ94) isolated from Lake Washington sediment samples were characterized. Based on phylogenetic analysis of 16S rRNA gene sequences the strains should be assigned to the genus Methyloversatilis. Similarly to other members of the family, the strains show broad metabolic capabilities and are able to utilize a number of organic acids, alcohols and aromatic compounds in addition to methanol and methylamine. The main fatty acids were 16:1ω7c (49–59 %) and 16:0 (32–29 %). Genomes of all isolates were sequenced, assembled and annotated in collaboration with the DOE Joint Genome Institute (JGI). Genome comparison revealed that the s…