There is a lot more information that you would need to provide in order to make a recommendation. What will you be observing? How long will you need the platform to stay aloft? How close is the launch point? In general, tasks that require a lot of close in maneuvering or observation would benefit from the use of a multi-rotor UAS/UAV. There are limitations to this, as they generally have low endurance (

It depends on your demands. Please specify payload, sensors, need for broadcasting video to ground, etc.

For fixed wings I'd recommend questuav ones, and for rotary, considering your area of interest, I'd say you need endurance over 30mins... that reduces drastically the options in the professional grade. Look at Microdrones MD4-1000 or wait 2 months and I'll offer you a much smaller quadcopter capable for +45mins flights. It is made by a spanish company I'm working with. It boasts dGPS capabilities allowing geo-tagging images within

Thank you very much for you Dear David for your valuable information

I am very appreciating from you Dear José Martínez-Rubio.

Your specific data needs will drive your sensor and aircraft selection.  You mention direct observation above, do you plan to use a visible light camera?  If so, what is the ground sampled distance you need to resolve?  Also, you will need to determine if and how accurately you need to georeference the imagery.  These are not difficult questions to answer, but you will need to in order  to ensure your acquired imagery provides the data you need to solve your problem.  Your data need drives your sensor selection, your sensor selection, environmental conditions, and mission profile drive your aircraft selection.  Good luck!

Dear ED thank you so much for your answer