Mathers MojoMOJO MATHERS (Green): It has been very interesting listening to the conversation. The level of ignorance about the ecological and economic values of mangroves has been rather alarmingly on display tonight. This bill is fundamentally flawed. It is a massive step backwards and it puts aside the protection for our environment that exists in the Resource Management Act (RMA) by overriding the processes that exist for controlling mangroves to enable as the bill's explanatory note says removing preventing controlling destroying and disposing of mangrove vegetation.The attitude of describing mangroves as a noxious weed and something that is going to take over the whole of New Zealand if we are not careful reveals a fundamental lack of understanding of the ecological value of mangroves in providing valuable and essential habitats for native fish for shellfish and for birds. That includes—and I hope that Scott Simpson is listening here—the banded rail which has all but disappeared from other areas.But also moving on from ecological values which are indisputable I also want to touch on the economic value of mangroves. They act as a natural shield against storm tide surges erosion and sea level rise. Rushing ahead with allowing the large-scale destruction of mangroves without going through the resource management process is a very short-sighted move that could prove extremely expensive in the long run. Mangroves have proven time and time again that they are extremely valuable protection and defence against storm surges because they dissipate wave energy. Very recently the Parliamentary Commissioner for the Environment highlighted that the extremely damaging storm surges which can cause massive amounts of erosion in one storm surge and are currently a once-in-a-hundred-year event are likely to occur every year with just half a metre of sea level rise. Every year we would have what is currently a once-in-a-hundred-year - level storm surge.The Waikato Regional Council's report on mangroves concluded: The mangrove forest provides a number of ecosystem services which mitigate the potential coastal erosion and inundation hazards that exist for the low-lying Hauraki Plains." Think about that. We are already seeing erosion from rising sea levels in many coastal areas of New Zealand and mangroves actually provide a very valuable soft-level defence. It is absolutely counter-productive to tear out a natural barrier against storm tides and erosion and sea-level rise when these people will later be crying "Oh we want to protect our property." and they want to build their extremely expensive concrete defences. That does not make economic sense. It does not make environmental sense and it does not make economic sense. If the National Government is serious about planning for climate change it will still regard mangrove swamps as its allies not as something to be destroyed and wiped out at a potentially enormous economic cost. It is just so illogical.It also ignores the reason mangroves are increasing and spreading over some areas. It boils down to the fact that the single thing that you could do that would be the most effective at limiting mangrove spread would be to reduce erosion and sedimentation. Why do we have sedimentation? Because of inappropriate land-use practices inappropriate harvesting of forestry in some places and overgrazing in others with increased rainfall events that are washing out far more soil into the bays. All of these factors combined are what are contributing to both the loss of valuable soil and the spread of the mangroves. But we also need to be seeing that mangroves are economically and ecologically valuable and the RMA is the place where these processes can be balanced out against each other. We should not be discarding that."