What has happened to our erflies and grhoppers etc.?

When I was a youngster our green and pleasant land was full of insects of all kinds.There was a huge variety of life in our streams and waterways.The air was plentiful with birds like the night-jar,the spotted fly catcher, finches,etc etc.What have we done.No more doormice,shrews,voles.and our food tastes like pap .I think that within 30 years it will be totally tasteless.It is not far off it now.My grandson is missing so much.