Navigation Links
The star of Africa's savanna ecosystems may be the lowly termite
Date:5/25/2010

CAMBRIDGE, Mass. -- The majestic animals most closely associated with the African savanna -- fierce lions, massive elephants, towering giraffes -- may be relatively minor players when it comes to shaping the ecosystem.

The real king of the savanna appears to be the termite, say ecologists who've found that these humble creatures contribute mightily to grassland productivity in central Kenya via a network of uniformly distributed colonies. Termite mounds greatly enhance plant and animal activity at the local level, while their even distribution over a larger area maximizes ecosystem-wide productivity.

The finding, published this week in the journal PLoS Biology, affirms a counterintuitive approach to population ecology: Often it's the small things that matter most.

"It's not always the charismatic predators -- animals like lions and leopards -- that exert the greatest control on populations," says Robert M. Pringle, a research fellow at Harvard University. "As E.O. Wilson likes to point out, in many respects it's the little things that run the world. In the case of the savanna, it appears these termites have tremendous influence and are central to the functioning of this ecosystem."

Prior research on the Kenya dwarf gecko initially drew Pringle's attention to the peculiar role of grassy termite mounds, which in this part of Kenya are some 10 meters in diameter and spaced some 60 to 100 meters apart. Each mound teems with millions of termites, who build the mounds over the course of centuries.

After observing unexpectedly high numbers of lizards in the vicinity of mounds, Pringle and his colleagues began to quantify ecological productivity relative to mound density. They found that each mound supported dense aggregations of flora and fauna: Plants grew more rapidly the closer they were to mounds, and animal populations and reproductive rates fell off appreciably with greater distance.

What was observed on the ground was even clearer in satellite imagery. Each mound -- relatively inconspicuous on the Kenyan grassland -- stood at the center of a burst of floral productivity. More importantly, these bursts were highly organized in relation to one another, evenly dispersed as if squares on a checkerboard. The result, says Pringle, is an optimized network of plant and animal output closely tied to the ordered distribution of termite mounds.

"In essence, the highly regular spatial pattern of fertile mounds generated by termites actually increases overall levels of ecosystem production. And it does so in such a profound way," says Todd M. Palmer, assistant professor of biology at the University of Florida and an affiliate of the Mpala Research Centre in Nanyuki, Kenya. "Seen from above, the grid-work of termite mounds in the savanna is not just a pretty picture. The over-dispersion, or regular distribution of these termite mounds, plays an important role in elevating the services this ecosystem provides."

The mechanism through which termite activity is transformed into far-reaching effects on the ecosystem is a complex one. Pringle and Palmer suspect termites import coarse particles into the otherwise fine soil in the vicinity of their mounds. These coarser particles promote water infiltration of the soil, even as they discourage disruptive shrinking and swelling of topsoil in response to precipitation or drought.

The mounds also show elevated levels of nutrients such as phosphorus and nitrogen. All this beneficial soil alteration appears to directly and indirectly mold ecosystem services far beyond the immediate vicinity of the mound.

While further studies will explore the mechanism through which these spatial patterns of termite mounds emerge, Pringle and Palmer suggest that the present work has implications beyond the basic questions of ecology.

"Termites are typically viewed as pests, and as threats to agricultural and livestock production," Pringle says. "But productivity -- of both wild and human-dominated landscapes -- may be more intricately tied to the pattern-generating organisms of the larger natural landscape than is commonly understood."

The findings also have important implications for conservation, Palmer says.

"As we think restoring degraded ecosystems, as we think about restoring coral reefs, or restoring plant communities, this over-dispersed pattern is teaching us something," he says. "It's saying we might want to think about doing our coral restoration or plant restoration in a way that takes advantage of this ecosystem productivity enhancing phenomenon."


'/>"/>

Contact: Steve Bradt
steve_bradt@harvard.edu
617-496-8070
Harvard University
Source:Eurekalert  

Related biology news :

1. Savanna habitat drives birds, and perhaps others, to cooperative breeding
2. Lowly termite, not the lion or elephant, may be the star of Africas savanna
3. Study shows genetically engineered corn could affect aquatic ecosystems
4. Genetically engineered corn may harm stream ecosystems
5. At the root of nutrient limitation, ecosystems are not as different as they seem
6. Resilience concepts poised to aid management of coastal marine ecosystems
7. First map of threats to marine ecosystems shows all the worlds oceans are affected
8. Map is first to track global human influences on ocean ecosystems
9. Adapting local ecosystems can soften impact of global climate change
10. Rats on islands disrupt ecosystems from land to sea, researchers find
11. Small streams mitigate human influence on coastal ecosystems
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
The star of Africa's savanna ecosystems may be the lowly termite
(Date:6/23/2017)... and ITHACA, N.Y. , June 23, ... University, a leader in dairy research, today announced a ... to help reduce the chances that the global milk ... of this dairy project, Cornell University has become the ... the Food Supply Chain, a food safety initiative that ...
(Date:5/6/2017)... 2017 RAM Group , Singaporean ... breakthrough in biometric authentication based on a ... to perform biometric authentication. These new sensors are based ... by Ram Group and its partners. This sensor will ... chains and security. Ram Group is a next ...
(Date:4/13/2017)... MONICA, Calif. , April 13, 2017 ... New York will feature emerging and evolving ... Summits. Both Innovation Summits will run alongside the expo ... of speaker sessions, panels and demonstrations focused on trending ... coast,s largest advanced design and manufacturing event will take ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... Singh Biotechnology today ... designation to SBT-100, its novel anti-STAT3 (Signal Transducer and Activator of Transcription 3) ... able to cross the cell membrane and bind intracellular STAT3 and inhibit its ...
(Date:10/10/2017)... , ... October 10, 2017 , ... Dr. Bob Harman, ... his local San Diego Rotary Club. The event entitled “Stem Cells ... and had 300+ attendees. Dr. Harman, DVM, MPVM was joined by two human ...
(Date:10/10/2017)... , ... October 10, 2017 , ... ... of 13 prestigious awards honoring scientists who have made outstanding ... a scheduled symposium during Pittcon 2018, the world’s leading conference and exposition for ...
(Date:10/9/2017)... Arizona (PRWEB) , ... October 09, 2017 , ... ... Kindred, a four-tiered line of medical marijuana products targeting the needs of consumers ... and packaging of Kindred takes place in Phoenix, Arizona. , As operators of ...
Breaking Biology Technology: