Assuming 2 GPM per head, and 9 heads running at the same time, that is 18 GPM. At 18 GPM through 1" poly you will lose about 8 PSI per 100'. So 400' will be 32 PSI or 74' of lose. The sprinklers will probably need 50 PSI to function properly, which is the same as another 115' of lift. Then we have to know the amount of actual vertical lift? Add the vertical lift to the 115' and 74', to get total head for the pump. Pump should be able to deliver 18 GPM at this head.
It will be almost impossible for a jet pump to draw water this far. You need to use a submersible in the river. Using the 275 gallon tank will only complicate the system, as you will now be double pumping the same water, and have two sets of everything to purchase and maintain. 275 gallons in the tank will only last about 10-15 minutes at 18 GPM flow, so both pumps would be running all the time anyway.
Now for controls. If you do not use any faucets or valves, and hook the pipe directly to the sprinklers, you can just throw on the breaker when you need water. If you control the pump this way, and someone closes a valve, or closes one of those spray handles on a hose, you will burn up the pump.
To be able to just turn on a faucet and have the pump come on automatically, you need a pressure tank and a pressure switch. However, with a pressure tank and a pressure switch, every sprinkler zone needs to be exactly 18 GPM or the pump will cycle on and off until it is dead. Adding a Cycle Stop Valve before the pressure tank, allows you to use any amount of water you desire without hurting the pump. And adding a Cycle Stop Valve will allow you to use a very small pressure tank, which more than offsets the cost of the CSV.