“…18 Duflo, Kremer, and Robsinson (2011) analyze farmer investments in fertilizer and is, therefore, not categorized as an Ag-E paper. 19 A large portion of this literature tests the outcomes of various tax and subsidy mechanisms to reduce nonpoint source (NPS) pollution (Alpízar et al 2004;Poe et al 2004;Spraggon 2004Spraggon , 2013Cochard et al 2005;Vossler et al 2006;Suter et al 2008;Spraggon and Oxoby 2010;Cason 2010;Cason and Gangadharan 2013;Suter and Vossler 2014;Miao et al 2016;Palm-Forster et al 2017, improve extraction of ground water for irrigation (Gardner, Moore, and Walker 1997;Suter et al 2012Suter et al , 2018Li et al 2014;Liu et al 2014), and incentivize land conservation and ecosystem service provision (Parkhurst et al 2002;Cason and Gangadharan 2004;Shogren 2007, 2008;Arnold, Duke, and Messer 2013;Banerjee et al 2014Banerjee et al , 2015Banerjee et al , 2017Fooks et al 2015Fooks et al , 2016Messer et al 2017;Duke et al 2017;Banerjee 2018).…”