How can the introduction of the invasive apple snail change the contribution of rice fields to greenhouse gas emissions and to biodiversity conservation in the Ebro Delta? 🧵 Thread below! - ThreadSky

nperezmendez.bsky.social • 72 days ago

How can the introduction of the invasive apple snail change the contribution of rice fields to greenhouse gas emissions and to biodiversity conservation in the Ebro Delta?
🧵 Thread below!

Comments

chikichanka.bsky.social•71 days ago

Buenísimo, Néstor!!!
Does the blue crab has any role on snal dynamics within fields? I guess they do in highly connected outflow channels, but crab access to fields is probably limited

nperezmendez.bsky.social•71 days ago

Indeed! The presence of blue crabs is mostly limited to well-interconnected outflow channels, but they are also present in some coastal rice fields (e.g. La Marquesa). I've not estimated apple snail populations in these fields but it would be interesting to assess potential crab-snail interactions.

chikichanka.bsky.social•71 days ago

my guess is that crabs would destroy snail populations... easy guess, after all! @bgallardo.bsky.social et al have already described that. But the interaction in rice fields (and its relation with other aquatic taxa and rice production) is really interesting!!
https://link.springer.com/article/10.1007/s10530-024-03334-1

nperezmendez.bsky.social•71 days ago

Yes, I know this paper of Vanessa, @bgallardo.bsky.social et al (nice study btw). It would be relatively easy to perform an exclusion experiment in crab-snail invaded fields to assess these potential links. Come to the Ebro Delta and we go for it!! 😜

nperezmendez.bsky.social•72 days ago

Flooded rice systems have been identified as important contributors to methane emissions because the anaerobic decomposition of OM, yet recent evidence show they can be also key C sinks. In the Ebro Delta, emissions concentrate during the fallow season (winter). https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0198081

nperezmendez.bsky.social•72 days ago

In the other side, the rice agroecosystem of the Ebro Delta, which occupies around 70% of the whole delta surface, is a keystone managed wetland of Western Mediterranean, serving as winter quarter for a broad range of migratory waterbirds from North Europe.

nperezmendez.bsky.social•72 days ago

In fact, until 2010 the regional government subsidized rice farmers to keep fields flooded during winter to support wintering waterbird communities. Yet the introduction of the invasive apple snail (Pomacea sp.) changed completely the rules of the game.

nperezmendez.bsky.social•72 days ago

The apple snail, which is in the top 100 worst invasive species worldwide, was accidentally introducing in the Ebro Delta during winter 2009-2010, triggering not only multiple environmental issues, but also a devastating impact on rice yield with losses of up to 100% of the harvest

nperezmendez.bsky.social•72 days ago

Among the first measures to slow down the spread of the apple snail in the Ebro Delta was to cancel the subsidies for winter flooding of rice fields. This aimed to promote field drying during the fallow season (winter), reducing the favorable conditions for the species' expansion.

nperezmendez.bsky.social•72 days ago

Changes in policies to fight against the snail (cancellation of subsidies for winter flooding) led to drastic changes in regional flooding patterns between the pre- and post-invasion stages. Average flooded area dropped from 65% of regional surface during pre-invasion to ~ 35% in the last 6 years.

Comments

Posting Rules

Reply