Paper summary assignment (due before spring break 2018)

2/22/2018

Here's a quick run-down of the blog post assignment I'm asking all of you to do!

Choose a peer-reviewed scientific paper from the primary literature (you can browse the "course readings" blog posts for suggestions, or just find your own paper of interest), write a short summary of the paper, including the following elements:
Paper citation
Purpose: 2 - 4 sentences
Methods: 1 - 2 sentences
Results: 2 - 4 sentences

And then write a bit (4 - 8 sentences) about how this study might be of interest to people practicing invertebrate conservation biology in Palau. This might require a bit of background reading, or you're welcome to come talk to Dr. Rundell or Jesse about it for ideas!

For those of you who have taken (or are taking) EFB 311, this will be a little like your Darwin Day posters, but without the figures. Avoid long quotations (and, obviously, don't plagiarize), and try to write for a general audience.

Example:

Citation:
Economo EP and Sarnat EM. 2012. Revisiting the ants of Melanesia and the taxon cycle: historical and human-mediated invasions of a tropical archipelago. Am Nat 180: E1–16.
http://www.antwiki.org/wiki/images/6/69/Economo_sarnat_2012.pdf

Purpose:
Economo and Sarnat describe the patterns of ant species richness and evolutionary history in Fiji, especially as they pertain to forest age and elevation. The authors do this with the framework of EO Wilson’s taxon cycle hypothesis, which predicts patterns of ant evolution on islands. EO Wilson wrote that ants that are more recent arrivals to islands in evolutionary time are more likely to live in edge habitats and/or secondary forests, whereas ants whose ancestors arrived on islands earlier on are more likely to live in less anthropogenically disturbed, interior, old-growth forests. However, EO Wilson predicted these things before we could confidently re-construct the evolutionary history of organisms, so Economo and Sarnat are among the first to test his ideas in a robust way.

Methods:
The authors bring together information on both ant distributions (based mostly on their own collection data) and phylogenies (based on DNA sequences). The authors focus on the genus Pheidole, which is the most species-rich ant genus (both in Fiji and in the world).

Results:
The ants with the deepest evolutionary history in Fiji tend to be from high elevation and interior forests. Anthropogenically introduced ants are most likely to be found in the lowlands. These findings are consistent with Wilson's (1959, 1961) observations about the way taxa are distributed in Melanesian islands, but do not form a full component of a "cycle."

Significance for Palau:
Palau probably has between half and 66% of the ant species richness that Fiji has, but it's species richness is divided up very differently. As far as we know (Jesse writing in early 2018), there are not any evolutionarily deep (>5my) radiations of ants in Palau. Most species are either recently diverged within the archipelago, or more closely related to something in nearby, larger islands (esp. PNG or Mindanao). Palau also doesn't have any elevation that exceeds ~200m, but has much more intact lowland tropical rainforest (mostly on the limestone karst), so the distribution of endemic species is likely to be somewhat different than the distribution of endemism in Fiji. The extent to which taxa diversify in islands seems to be related to dispersal ability and island area: organisms that are good at dispersing (e.g., birds, bats) don't diversify in small islands, but organisms that are poor dispersers (e.g., snails) often do. Different ants likely span the range of dispersal ability between small birds and diplommatinid snails, so they're kind of a cool taxon to examine for patterns of endemism. In general, this paper is an important one to read in the broader context of terrestrial conservation in tropical Pacific islands, but it also stands in contrast to many of the distinct features of Palau and its biota.

4 Comments

Haley Korcz

3/8/2018 08:51:51 am

Citation:
Golbuu, Y., Victor S., Wolanski, E., Richmond R.H. (2003) Trapping of fine sediment in a semi-enclosed bay, Palau, Micronesia. Estuarine, coastal and shelf science, 57, 941-949.

Purpose:
The purpose of this study was to collect data regarding the high sediment loading in Airai Bay that is smothering corals and creating a habitat shift from coral dominance to algae dominance. Airai Bay is semi-enclosed on the southeast coast of Palau, which is protected from tidal currents and the local winds are not strong enough to re-suspend the settled sediment. Environmental degradation like poor land use practices and destroying mangroves surrounding Airai Bay could be having a major impact of this coral reef system that is very ecologically and economically important.

Methods:
The researchers developed five stations that were used as testing sites in Airai Bay from the end of the Ngerikiil River to the mouth of the bay. They measured the vertical profile of the water column including salinity, temperature, and suspended sediment concentration at all the stations. At station one the mangrove swamp, they set up sediment traps on the river banks to determine how much sediment was being captured within the mangroves. Rainfall amounts were provided by the National Weather Service and during the time of the study two floods occurred.

Results:
At station 1 during river floods, the SSC (suspended sediment concentration) reading showed that the waters were very turbid as they exceeded the nephelometers saturation level. SSC was also higher at rising tide then during low runoff periods showing that sediment is being brought into the bay and settling in the mangroves. Following a river flood the river plume, freshwater exiting the estuary, could be traced though each stations readings. The readings at each station suggested that the sediment was being diluted, by lowering SSC and higher salinity levels. Based on the study’s results only about 2% of sediment is being exported out of the bay.

Significance for Palau:
Airai Bay is accumulating about 98% of the riverine sediment, which is an extremely high sediment loading. This is smothering corals and increasing turbidity which further stresses the system due to low light access and decreasing larval recruitment. These stressors are causing ecologically issues which is now effecting the local fisheries economy. In order for the ecosystem to restore itself the stressors would need to be lowered. The mangroves that are being cleared are exceptional at trapping sediment, lowering the sedimentation rate about 15-30% before the river plume continues throughout the bay. In order for the people of Palau to conserve this coral reef system, mangroves need to be stop being cleared and actually expanded. If the mangrove swamp had a higher land area, it would be able to trap more sediment. The next step in conservation efforts would be to educate and develop better land use practices. Perhaps during the nine-month period of heavy rainfall agricultural fields could be required to have a cover crop to prevent soil erosion. Lowering soil erosion without impacting the agricultural economy would be another important step to conservation and finding a balance between agriculture and fisheries.

Jack Zeng

3/9/2018 07:46:46 am

The purpose was written well in introducing a background on Airai Bay and outlining the impacts of outside interference. The methods was also sufficient although it was more lengthy than required. However, the results contained a few scientific jargon words that I had little idea about. Both scientists and the general public in Palau may read our entries so it would be best if the results were simplified and easier to read. Explaining the consequences of such a high amount of sediment buildup was a good idea but adding more detail about the ecological issues caused by these stress factors would help stress the significance of this paper for conservation in Palau. Proposing potential solutions is interesting but I think the entry should also focus on how the paper is ecologically important in the context of Palau. Although there are a few grammatical errors present, this entry was good overall.

Jack Zeng

3/8/2018 08:36:26 pm

Citation:
Iwase, A., Sakai, K., Suzuki, A., & van Woesik, R. (2008) Phototropic adjustment of the foliaceous coral Echinopora lamellosa in Palau. Estuarine, coastal and shelf science, 77, 672–678. https://doi.org/10.1016/j.ecss.2007.10.022
Purpose:
Iwase et al. (2008) outline the concept of morphological adjustments by corals in response to wave action and light intensity. Many coral species have the ability to change their growth forms in response to light intensity while other coral species can only change their shape to a small extent. The coral species that express the latter for instance, may grow their branches toward the light or change the shape of their plates to maximize light intake. What previous studies didn’t focus on is the capacity of foliose corals (corals that can change shape to a small extent) in changing the shape of their plates to increase the number of tissue exposed to light.

Methods:
The researchers measure the angle of colonies of Echinopora lamellosa at various elevations of steep hills where light intensity is highest. They also produce a light model calculating both sun elevation and shade at any time and any location.

Results:
Foliose corals can change how much tissue on plates are exposed to light and E. lamellosa in particular can slightly change shape to look like it’s leaning with its plates taking on the shape of parabolic antennas. However, results show that sunlight intensity isn’t necessarily the only factor, suggesting that atmospheric diffusion or other factors may play an important role as well.

Significance for Palau:
Palau has a very rich diversity of coral communities because of its decent variety of reef habitats and lagoons. Reef flats around specific islands are quite notable for housing diverse coral communities even though the somewhat clear water limits visibility from the surface to between 10 and 12 meters. The diversity at these conditions shows the incredible adaptability of corals in limited sunlight. The paper by Iwase et al. may highlight the importance of morphological adjustments of corals in Palau and around the world when sea level increases with climate change and less sunlight reaches the corals underwater. Additionally, higher pollution levels in the air or from nutrient runoff may further diffuse sunlight intensity although corals may adapt very quickly and survive until conservation efforts are directed to coral reefs.

Zakery T Ward

3/15/2018 09:23:00 am

Citation:
Barry, J.P., Widdicombe, S., & Hall-Spencer, J.M. (2011) Effects of ocean acidification on marine biodiversity and ecosystem function. Ocean acidification, 192–209.
Purpose:
Barry, Widdicombe, and Hall-Spencer discussed the effects of ocean acidification on marine ecosystem functions and biodiversity, they focused far more on the large-scale issues and implications that controlled experiments cannot show in their limited scale. Large environmental changes can have broad effects on biodiversity, these effects can affect energy flow and other processes by the loss of keystone species who contribute to these processes. Other studies look at the survival of a single species and assumed that changes in the species effects the environment.
Methods:
The paper breaks up the topic into seven board categories and focus on how ocean acidification effects each.
Results:
Acidification of the ocean has effects that goes deeper than just a raise in ph of the water. It effects some of the earths most sensitive habitats. It also means that the servers that we rely on from the ocean will be affected negatively, from fishing to tourism. This problem is larger than most understand.
Significance for Palau:
As an island nation surrounded by the ocean and where fishing is a large part of the local’s life. During a lecture Dr. Rundell talked about how sea cucumbers are a large resource for the people of Palau. Along with the coral reefs many of the marine invertebrates are going to be directly affected by acidification. Any of the invertebrates who use calcium carbonate to make their skeletons it becomes harder for them to make their skeletons strong. This could lead to higher rates of predation and a reduction in prey populations.

Paper summary assignment (due before spring break 2018)

Leave a Reply.

Rebecca Rundell & Jesse Czekanski-Moir

Archives

Categories