Ecosystem functioning and intrinsic value of biodiversity

Trying to show the importance of biodiversity for ecosystem functioning, ecologists are repeatedly looking for a possible connection between species diversity and intensity of various ecosystem processes. However it appears that simple "proof" of such a connection cannot easily be demonstrated and involves a lot of contingencies. The different meanings of "ecosystem functioning" may be crucial for attempts to show the importance of biodiversity and to assess possible redundancy. if "ecosystem functioning" means only total production of organic matter or consumption of CO2 then some degree of redundancy in species diversity of autotrophs will be obvious in most cases. However if "ecosystem functioning" includes the synthesis of all compounds that plants, animals and other organisms of a given community contain in their bodies or release in the environment, then any decrease in species diversity will be meaningful and any redundancy will be impossible by definition. In accordance with such a definition triodiversity obviously cannot be diminished without some loss of ecosystem functioning. I emphasize that attempts to conserve biodiversity do not need special justification in possible relationships between diversity and ecosystem services. If biodiversity has intrinsic value it means that it could in principle be "useless" for human needs or for "ecosystem functioning".