A simple device for field studies of animal activity

1983 ◽  
Vol 61 (6) ◽  
pp. 1401-1404 ◽  
Author(s):  
Lucius Stebbins ◽  
David Daisley

A reliable and simple device suitable for long-term recording of activity in natural environmental conditions is described. It is inexpensive to make, assembled with standard electronic components, and adaptable for a wide range of animal sizes. Instructions for assembly which can be interpreted with a minimum of electronics knowledge and parts lists with catalog numbers for a common Canadian electronics retailer are provided.

2008 ◽  
Vol 48 (3) ◽  
pp. 296 ◽  
Author(s):  
C. J. Birch ◽  
G. McLean ◽  
A. Sawers

This paper reports on the use of APSIM – Maize for retrospective analysis of performance of a high input, high yielding maize crop and analysis of predicted performance of maize grown with high inputs over the long-term (>100 years) for specified scenarios of environmental conditions (temperature and radiation) and agronomic inputs (sowing date, plant population, nitrogen fertiliser and irrigation) at Boort, Victoria, Australia. It uses a high yielding (17 400 kg/ha dry grain, 20 500 kg/ha at 15% water) commercial crop grown in 2004–05 as the basis of the study. Yield for the agronomic and environmental conditions of 2004–05 was predicted accurately, giving confidence that the model could be used for the detailed analyses undertaken. The analysis showed that the yield achieved was close to that possible with the conditions and agronomic inputs of 2004–05. Sowing dates during 21 September to 26 October had little effect on predicted yield, except when combined with reduced temperature. Single year and long-term analyses concluded that a higher plant population (11 plants/m2) is needed to optimise yield, but that slightly lower N and irrigation inputs are appropriate for the plant population used commercially (8.4 plants/m2). Also, compared with changes in agronomic inputs increases in temperature and/or radiation had relatively minor effects, except that reduced temperature reduces predicted yield substantially. This study provides an approach for the use of models for both retrospective analysis of crop performance and assessment of long-term variability of crop yield under a wide range of agronomic and environmental conditions.


Author(s):  
Emily W. B. Russell Southgate

There are many field techniques that take research beyond what can be found in written documents. Clues to the past are hidden in such subtle (and not so subtle) features as topographic modifications, soils, and tree trunks. Field studies search for evidence of conditions and for their resultant effects through a variety of techniques. Features may be evident from a ground survey, located precisely through GPS. Remote imaging, using a variety of techniques from simple aerial photography to lidar, reveal hidden patterns, that may then be studied on the ground. Archeological study relates the patterns found on the ground to human activities, as they have changed over time. Dendroecology interprets records left in tree rings. Some studies look at stands of different ages to study change over time, and long-term studies trace change in individual stands. In these field studies that look at the past, soil characteristics and materials hidden in the soil, such as DNA, stable isotopes and charcoal, can reveal details of past processes and species. These methods are illustrated with examples from a wide range of biomes.


2021 ◽  
Author(s):  
Silvia Fontana ◽  
Lan-Wei Yeh ◽  
Shing Hei Zhan ◽  
Shao-Lun Liu

Invasive freshwater macroalgae are rarely described. Recently, a freshwater red alga, Montagnia macrospora, was introduced from South America to East Asia via the global aquarium trade. The earliest reported occurrence of this alga in Taiwan was dated 2005. To determine whether or not M. macrospora has become an invasive species in Taiwan and to understand its traits that facilitated its invasion, we took a total-evidence approach that combines ecological background examination and population genetic analysis. Our island-wide survey showed that this alga is widespread in the field in Taiwan, where the climate greatly differs from that of South America. Our population genetic analyses showed that the cox2-3 sequences were identical in all the samples of M. macrospora from Taiwan, consistent with our observations that the alga mainly expanded through asexual reproduction. Furthermore, our long-term ecological assessments and field observations revealed that M. macrospora can grow under a wide range of environmental conditions (e.g., temperature, pH, and light conditions), self-sustain for nearly a decade, and bloom in polluted waters. Taken together, these data suggest that M. macrospora has successfully invaded the freshwater ecosystems in Taiwan due to its ability to undergo asexual reproduction and to self-sustain under broad environmental conditions. We hope that our study brings attention to invasive freshwater algae, which have been overlooked in conservation planning and management.


2018 ◽  
Vol 15 (8) ◽  
pp. 463 ◽  
Author(s):  
Johan Fahlman ◽  
Jerker Fick ◽  
Jan Karlsson ◽  
Micael Jonsson ◽  
Tomas Brodin ◽  
...  

Environmental contextEnvironmental persistence of excreted pharmaceuticals in aquatic ecosystems is usually predicted using small-scale laboratory experiments assumed to simulate natural conditions. We studied five pharmaceuticals comparing their removal rates from water under laboratory conditions and under natural environmental conditions existing in a large pond. We found that the laboratory conditions did not fully capture the complexity within the pond, which led to different removal rates in the two systems. AbstractEnvironmental persistence is a key property when evaluating risks with excreted pharmaceuticals in aquatic ecosystems. Such persistence is typically predicted using small-scale laboratory incubations, but the variation in aquatic environments and scarcity of field studies to verify laboratory-based persistence estimates create uncertainties around the predictive power of these incubations. In this study we: (1) assess the persistence of five pharmaceuticals (diclofenac, diphenhydramine, hydroxyzine, trimethoprim and oxazepam) in laboratory experiments under different environmental conditions; and (2) use a three-month-long field study in an aquatic ecosystem to verify the laboratory-based persistence estimates. In our laboratory assays, we found that water temperature (TEMP), concentrations of organic solutes (TOC), presence of sediment (SED), and solar radiation (SOL) individually affected dissipation rates. Moreover, we identified rarely studied interaction effects between the treatments (i.e. SOL×SED and TEMP×SOL), which affected the persistence of the studied drugs. Half-lives obtained from the laboratory assays largely explained the dissipation rates during the first week of the field study. However, none of the applied models could accurately predict the long-term dissipation rates (month time-scale) from the water column. For example, the studied antibioticum (trimethoprim) and the anti-anxiety drug (oxazepam) remained at detectable levels in the aquatic environment long after (~150 days) our laboratory based models predicted complete dissipation. We conclude that small-scale laboratory incubations seem sufficient to approximate the short-term (i.e. within a week) dissipation rate of drugs in aquatic ecosystems. However, this simplistic approach does not capture interacting environmental processes that preserve a fraction of the dissolved pharmaceuticals for months in natural water bodies.


2012 ◽  
Vol 279 (1749) ◽  
pp. 5048-5057 ◽  
Author(s):  
Fyodor A. Kondrashov

A subject of extensive study in evolutionary theory has been the issue of how neutral, redundant copies can be maintained in the genome for long periods of time. Concurrently, examples of adaptive gene duplications to various environmental conditions in different species have been described. At this point, it is too early to tell whether or not a substantial fraction of gene copies have initially achieved fixation by positive selection for increased dosage. Nevertheless, enough examples have accumulated in the literature that such a possibility should be considered. Here, I review the recent examples of adaptive gene duplications and make an attempt to draw generalizations on what types of genes may be particularly prone to be selected for under certain environmental conditions. The identification of copy-number variation in ecological field studies of species adapting to stressful or novel environmental conditions may improve our understanding of gene duplications as a mechanism of adaptation and its relevance to the long-term persistence of gene duplications.


Author(s):  
О. V. Levakova ◽  
L. М. Eroshenko ◽  
А. N. Eroshenko

The article presents and analyzes data of competitive varietal testing of promising varieties and lines of spring barley for yield and brewing qualities. Field studies were conducted in 2014–2017 on dark gray forest heavy loam soil. Agrochemical parameters are total nitrogen – 0.24%, humus content in a layer of 0-40 cm (according to Tyurin) – 5.19%, hydrolysis nitrogen – 123.5 mg / kg, salt extract pH – 4.92 mg-eq / 100g; labile phosphorus - 34.6 mg / 100g, labile potassium – 20.0 mg / 100g. The forerunner is winter wheat. Meteorological conditions in the years of research differed from each other and from the average long-term value. Barley samples were assessed by the protein content in the grain (GOST 10846-91), extract content (GOST 12130-77), weight 1000 grains (GOST 10842-89). Ecological plasticity was determined by the method proposed by E.D. Nettevich, A.I. Morgunov and M.I. Maksimenko, stability index (Ľ) by A. A. Gryaznov, indicator of stability level (Puss) by E. D. Nettevich and A. I. Morgunov. The main measure for assessing quality indicators is protein content. Many other biochemical and technological features of grain depend on its level. The experimental data convincingly testify to the significant influence of the soil and climatic conditions on the yield and, especially, on the brewing qualities of barley in the conditions of the Central Region of the Nonchernozem Zone. According to the studied traits, new valuable varieties Nadezhny, Sir, Noble and selection lines 141 / 1-09 h 746, 23 / 1-10 h 784, distinguished by high adaptability and resistance to adverse environmental factors, have been identified.


2020 ◽  
pp. 66-73
Author(s):  
A. Simonova ◽  
S. Chudakov ◽  
R. Gorenkov ◽  
V. Egorov ◽  
A. Gostry ◽  
...  

The article summarizes the long-term experience of practical application of domestic breakthrough technologies of preventive personalized medicine for laboratory diagnostics of a wide range of socially significant non-infectious diseases. Conceptual approaches to the formation of an integrated program for early detection and prevention of civilization diseases based on these technologies are given. A vision of the prospects for the development of this area in domestic and foreign medicine has been formed.


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