Complex sentence: Many tunnel and field studies have been conducted to show the potential effects of imidacloprid in the natural environment however most of these field studies have design and implementation deficiencies, which make them difficult to interpret and use.
Split into simpler sentences: Many tunnel and field studies have been conducted to show the potential effects of imidacloprid in the natural environment. Unfortunately, most of these field studies have design and implementation deficiencies, which make them difficult to interpret and use.