Mulch residue has been measured at levels of 50 to 260 kg per hectare in topsoil in areas where mulch use dates back more than 10 years, which confirms that mulching is a major source of both microplastic and macroplastic soil contamination.
mˈʌltʃ ɹˈɛsɪdˌuː hˈæzbiːn mˈɛʒɚd æt lˈɛvəlz ʌv fˈɪfti tə tˈuːhˈʌndɹɪd sˈɪksti kˌeɪdʒˈiː pɜː hˈɛktɛɹ ɪn tˈɑːpsɔɪl ɪn ˈɛɹiəz wˌɛɹ mˈʌltʃ jˈuːs dˈeɪts bˈæk mˈoːɹ ðɐn tˈɛn jˈɪɹz, wˌɪtʃ kənfˈɜːmz ðæt mˈʌltʃɪŋ ɪz ɐ mˈeɪdʒɚ sˈoːɹs ʌv bˈoʊθ mˌaɪkɹoʊplˈæstɪk ænd mˌækɹəplˈæstɪk sˈɔɪl kəntˌæmᵻnˈeɪʃən.