A new methodology for the assessment of large woody debris accumulations on highly modified rivers (example of two French piedmont rivers)

absorption bois mort calidad del agua cours d'eau crop residues cursos de agua deadwood desechos de la madera forest litter grume hojarasca forestal logs madera muerta mathematical models measurement mesure methode methodology methods peso poids pollution de l'eau residuos de cosechas rivers trozas volume volumen water pollution water quality weight wood residues