Very difficult to think of genuinely emerging issues rather than 'increasing effects of...' climate change, globalisation, etc. Issues to do with light and noise pollution are perhaps less well studied, particularly as new technologies emerge?

Dear Margaret

I think "urban ecosystem" must be given special attention because it is an artificial ecosystem. Indeed, the human concentration in cities and expanding urbanization generate a new ecosystem that is superimposed and interferes with the natural ecosystem: the urban ecosystem. An ecosystem is exposed to constant changes that can compromise its coherence and resilience. So it is always in unstable equilibrium, that is, in a situation of dynamic crisis. This is the case of the urban ecosystem that needs an increasingly wide area to meet its needs and compensate for impacts, and is characterized by a growing ecological footprint. One of the goals of sustainable development is to identify or reduce this footprint. It seems to me that the major challenges in the urban ecosystem are represented by the major hazards: floods, earthquakes, and also risks of industrial units explosions to toxic pollutants population.

Best regard

FADEL

I agree with Margaret, that it is hard to identify emergences, as they "suddenly" occur in complex adaptive systems like the urban social-ecological systems. Following the path, which Frank Geels showed in his book (first link added here), we can try to identify niches of technological innovations and try to intertwine them with what we know about our current state of urban reality. So actually emerging issues are there in front of us, but hard to grasp, I think. I would think about

Maybe some are going beyond the subject of Urban Ecosystems and Environment, but I think disciplines and fields need to merge to produce useful and holistic knowledge for upcoming challenges.

http://site.ebrary.com/lib/alltitles/docDetail.action?docID=10471418

https://publicwiki.deltares.nl/display/BWN/Guideline

Dear Jacqueline,

Thank you for sharing this interesting question. In order to help other researchers develop interesting answers, we should think about :

- Technological threats or opportunities to urban ecosystems poorly recognized;

- Natural threats or opportunities to urban ecosystems poorly recognized;

- Anthropic threats or opportunities to urban ecosystems poorly recognized.

How about organizing an international conference that will address these three categories of issues ? 

Regards, 

Juste

One more source for measuring:

Kitchin et al. 2014: Knowing and governing cities through urban indicators, city benchmarking and real-time dashboards

http://rsa.tandfonline.com/doi/full/10.1080/21681376.2014.983149#.VMUdzS7fHoY

Dear Alessandro,

The "measuring issues" in urban sustainability is definitely a subject of interest. My PhD thesis is addressing some of these issues, including : i) the interpretation of the sustainability indicators following their measurement; ii) the development of sustainability threshold; and iii) the comparison of the different methodological approaches. Perhaps, we could further discuss the subject and share some of our projects.

Best regards,

Juste

Agree that is hard to pinpoint specific threats for urban ecosystems. Perhaps the trend to reduced section sizes, so greater hard surface to vegetation ratios. In a recent survey of 55 Dunedin gardens we found, amongst other things, quite a high species richness, and surprisingly high proportion of Coleoptera species that were native cf. exotic. The study involved analysis of the vegetation in gardens, and a social component examining biodiversity awareness.  

The other side of this coin is the problem of urban sprawl and loss of productive land near cities.

Hello Jacqueline

i assume this symposium will focus not on issues globally but in NZ? Pacific? Southern Hemisphere? As most of the previous comments emphasise the importance of the "human dimension" - therefore it is v. important to know the social framework. I think you did not specify this in the question.

One thin gthat vexes me is that the world is becoming more and more urban, in terms of number of people living in urban araes. Yet their perceptions and values influecne how the countryside is managed. How does this happen? How do they proejct their values "outside"? This is a sociaological question but perhaps not ottally independetn of urbanisation, because of the increasing flow of materails and good between urban areas and the "countryside".

The other is the role of native vs. non-native species in the ecological processes in urbanisaed areas.  Many present the urban areas as invasion foci - but I know of not many quantitative summaries of this effect (I am not talking here about the no. of non-native species in urban areas. I am talking about their ecological role and its quantification. Also the role of native species - Barbara's comment raises the question that the native species present in gardens are "passengers" or "drivers"? Is this  a uniquely NZ phenomenon -which it could be-, or more general?)

However, these are not yet "horizon" questions. Maybe you should run a workshop devoted to horizon scanning?

An aside: I do not think that urban ecosystems can be classified as "novel" etc. - they are well embedded in the local landscapes, and very likely have a v. strong local imprint - for example, when we compared ground beetle assemablages among various European ciites, the local signature was much stronger than the "urbanisation signature" - i.e. there was greater similarity among various urbanisaiton stages in a country than within urbanisation stage and among countries. I.e. various urbanisation stages within a country always showed higher similarity to each other than the urban assemblage structure among various countries or regions - even when we considered Finland, Denmark and Belgium or Germany.

Good lukc with the symposium

Gabor

Thanks Gabor - we are running a horizon scanning workshop to look at emerging global issues for urban environments. The answers posted here will contribute to the horizon scan.  I am interested in the study you mention comparing beetle assemblages among European cities.  Is this published and if so can you provide the citation please?

Did you consider the planting of various exotic herbs, shrubs or trees in the gardens which can then "escape" and become invasive and very costly for the administrations and citizens ?

Sure Jaqueline; we pulbished a few articles. Will find your e-mail and send.

Greetings

Gabor

Dear Jacqueline, Whilst simplistic, it seems to me that whilst we are all looking at the huge and growing rates of consumption in both the global North & South, we are failing to realise that this is leading to a collinear increase in the amount of waste we are producing. We will soon be buried in our waste (in both senses of the word) products, in a situation similar to the 'Shoe event horizon' of Douglas  Adams Hitchhikers Guide to the Galaxy series many years ago. 

Cheers, Doug