跳至主要内容

Effect of Transient Acid Spikes on Developmental Stages of Lepomis Fishes

There is a developmental sensitivity to pH for most aquatic organisms. Ocean acidification due to increasing amounts of carbon dioxide is a current and future problem for organisms with the gradual lowering of the ocean pH. Carbon dioxide increases also can affect freshwater systems, but episodic acidity causes more problems with organisms in poorly buffered streams, ponds and lakes.

In this paper, the effects of transient acid spikes on development of Lepomis sunfish were studied by combining field work with laboratory studies. Lepomis sunfish eggs were collected from rocks on nests in two freshwater ponds and tested for their resistance to laboratory induced transient acid spikes. Fertilized eggs on rocks within the same nest were used for each pH transient experiment. Egg masses on one rock from the nest were used as a control while egg masses on another rock were exposed to transient acid spikes. Overall, 3163 early-life-stage Lepomis individuals (2459 eggs, 309 pre-swim-up larvae, and 395 Post-Swim-Up fry) taken from seven different nests were exposed to acid conditions in these experiments; another 1592 control individuals from the same nests were grown to the Post-Swim-Up stage in non-acid conditions.

The experiment findings indicated that various stages of development showed different responses to the acidic effects. The survival was high in the controls (94.0%); survival for groups exposed to acid water ranged from 85.5% to 0% (data pooled for groups with the same pH, duration of acid exposure, and life-stage). The major stages studied were fertilized egg, hatched with attached yolk sac, and free swimming with gills. The acid sensitivity followed development stages with the most acid sensitive stage being free swimming with gills.

In conclusion, this fieldwork-laboratory data chain supports earlier field studies, providing the final link in an evidentiary chain showing the effects of transient acid spikes on Lepomis hatching profiles in freshwater ponds.

Article by William G. Hagar, et al, from University of Massachusetts Boston, Boston, USA.

Full access: http://mrw.so/1aHM3G
Image by Matthieu Berroneau, from Flickr-cc.


评论

发表评论

此博客中的热门博文

Electron Spin and Proton Spin in the Hydrogen and Hydrogen-Like Atomic Systems

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52202#.VIj7tMnQrzE Author(s) Stanisław Olszewski * Affiliation(s) Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland . ABSTRACT The mechanical angular momentum and magnetic moment of the electron and proton spin have been calculated semiclassically with the aid of the uncertainty principle for energy and time. The spin effects of both kinds of the elementary particles can be expressed in terms of similar formulae. The quantization of the spin motion has been done on the basis of the old quantum theory. It gives a quantum number n = 1/2 as the index of the spin state acceptable for both the electron and proton ...
发表评论
阅读全文

A Study on the Seismic Isolation Systems of Bridges with Lead Rubber Bearings

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52566#.VJt06cCAM4 Author(s)   Woo-Suk Kim , Dong-Joon Ahn , Jong-Kook Lee Affiliation(s) School of Architecture, Kumoh National Institute of Technology, Gumi, Republic of Korea . ABSTRACT This study consists of the development and presentation of example of seismic isolation system analysis and design for a continuous, 3-span, cast-in-place concrete box girder bridge. It is expected that example is developed for all Lead-Rubber Bearing (LRB) seismic isolation system on piers and abutments which placed in between super-structure and sub-structure. Design forces, displacements, and drifts are given distinctive consideration in...
发表评论
阅读全文

Effects of Karate Training on Basic Motor Abilities of Primary School Children

“You never attack first in karate” might be the best conclusion of karate, which is a martial art practiced typically without weapons. It’s reported that karate has a long history for several hundred years, but the modern karate was spread to the whole Japan from Okinawa in the early part of 20th century. Now it has become one of the most widely practiced martial art forms in the world. Usually, it’s divided into Kihon, Kata and Kumite. As for the beginners, Kihon is more suitable for them because it involves basic techniques. Due to karate consists of dynamic offensive and defensive techniques using all parts of the body to their maximum advantage, the best understanding of true karate practice is the perfection of oneself through the perfection of the art. It not only develops coordination, quickens reflexes, and builds stamina, but also develops composure, a clearer thought process, deeper insight into one’s mental capabilities, and more self-confidence. So many researchers stu...
发表评论
阅读全文