Please post any specific comments on the conceptual framework for indicator selection relevant for marine sites only in this section.

Dear all,

The forum debate about Action 2 document on parameters and indicators has suffered of a quite evident lack of aquatic (both marine and freshwater!) inputs: I make this criticism primarily to myself!

I am sure that during the A2 meeting in Halle we will have time to speak each other thoroughly, during the plenary sessions and, in particular, in the working groups, finally coming out with a coherent and fruitful aquatic contribution to the document and to Action 2 in general.

I admit my difficulties to adapt some concepts of the document to the aquatic ecosystems, but I think also that the possibility to merge the aquatic with the terrestrial view is maybe one of the most stimulating activities of A2 and of the project in general.

Following some discussions with the Italian freshwater and marine colleagues, we try to evidence some doubts/questions that may be possible points of discussion within the aquatic communities during the meeting:

1) List of LTER parameters (in paragraphs 4.2): we have sent to Mark some additional parameters to be added to the list, concerning mainly the water properties (e.g. : mixing depth), biological compartments (e.g. heterotrophic and autotrophic prokaryotic; autotrophic and heterotrophic protists; etc etc); within the biotic compartments, also some metabolic information have been added (beside PP, also bacteria production, respiration….): I think that we should arrive to a whole condivision of the  list during the meeting.

2) It is not so straightforward how to match the aquatic parameters with ecological integrity indicators (see tables 6/1-6/3). Some categories (e.g. energy budget) are not of a largely widespread use in the aquatic communities, as far as I know, and we need to arrive to a common vision.

3) There are some difficulties in the definition of “ecological integrity” in practice. Not for all the ecosystem it is possible to find a “near-natural” state.  Which should be, then,  the "reference baseline"? The one given by our own long-term data series (“shifting” with their length)? The one given by our LTER data + some kind of modelization? I think that our LTER community should give some clear indications to this topic that is a matter of debate also within other EU initiative (se, e.g., WFD)

4) The same can be said to the representation of ecological integrity parameters (Fig 5 of the report) with this very nice and meaningful “spider web” graphs: I think that we need some discussion about their use (or introduction?) also in aquatic ecosystems and about hoe to set the "100 % normalization".

5) The goods and services coming from the aquatic ecosystems should be better defined with our contribution: fisheries, harvesting, drinking water, recreations (bathing, tourism….) and so on. At the same time, some important phenomena that may affect the aquatic ecosystem services must be dealt with (e.g. algal blooms, anoxia, toxic algae, trophic mismatch….) and we have introduce them as important indicators and/or parameters.

Warm regards to all

Alessandra

Dear Allessandra and all,

thanks for your comments. You are totally right that marine (and freshwater) systems are underrepresented in the concept up to now. I really hope to get more input for these parts during the meeting and the project time.

Regarding ecological integrity, it is not needed to include a "near natural" state - we can also compare sites with each other or at different time steps and look for changes in their integrity and capacitites to provide services. Actually we did this for the German North Sea, where we linked different models in order to compare the current state of the marine system with a future state, including high numbers of offshore wind mills. There we also applied the ecological integrity indicators for a marine system. The paper is here: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W87-4X36TTD-1&_user=2387607&_coverDate=01%2F31%2F2011&_alid=1561494736&_rdoc=2&_fmt=high&_orig=search&_origin=search&_zone=rslt_list_item&_cdi=6647&_sort=r&_st=13&_docanchor=&view=c&_ct=6&_acct=C000056415&_version=1&_urlVersion=0&_userid=2387607&md5=8044b5df427e8dfb89205cd234ac762a&searchtype=a

Regarding goods and services, I think we will be able to define specific indicators for aquatic systems. About how to make/interpret spider diagrams, I am sure we will find time in Halle to discuss this. In the paper mentioned above, we derived one for marine ecosystems also.

So much for today, looking forward to the meeting,

best regards, Benjamin