Of course, they have direct relations and check the number of wetlands lost anywhere. But with the same climate variabilities do not forget that management (human interference strongly affects it). For example, look at the trends of the wetlands of Lake Tana in Ethiopia. It is climate variability but management that aggravates the degradation of the wetland. Second, look at the wetland of Lake Alemaya in the eastern parts of the country, which was once the swampy area. It was completely destroyed by management, not climate or weather variability! I think you access many documentations about it.

Here is one suggestion as to a starting point. Article Global pattern for the effect of climate and land cover on water yield

If you follow the papers they cite, and look for papers that cite this paper, you should be able to chase down what you need.

As was already mentioned, in much of the world the effects of human water use/management, as well as human changes to land-use and vegetative cover in areas outside a wetland, dwarf the effects of climate variability. The diversion of water can be equal to a very severe drought.

You can correlate climate parameters against wetland ecological factors across a few different wetlands :)

There are statistical links between hydrometeorological variables and spaces, whether natural or anthropized. If we can compare the trend of hydrometeorological variables with evolution of land use in highly urbanized areas, it is also possible to compare it with wetlands degradation in a region. However, care must be taken in interpreting the results obtained because they will depend on the time scale of your study and reasons for degradation of the environment studied.

Debe estudiar y evaluar si existe correlacion entre las dos cosas y una de las primeras tareas seria medir el comprtamento de la precipitacion q cae en los puntos de recarga.