@article{fdi:010042495,
  title = {{P}lant species richness and floristic composition change along a rice-pasture sequence in subsistence farms of {B}razilian {A}mazon, influence on the fallows biodiversity ({B}enfica, {S}tate of {P}ara)},
  author = {{M}itja, {D}anielle and {M}iranda, {L}. {D}. {S}. and {V}elasquez, {E}lena and {L}avelle, {P}atrick},
  editor = {},
  language = {{ENG}},
  abstract = {{A}long the {A}mazonian pioneer front in the {B}razilian state of {P}ari, smallholder farmers manually clear primary rain forest every year to grow rice prior to sowing pastures that they will use for 5-20 years. {S}pecies richness and floristic composition of the weedy species were studied in 20 plots along a farming succession, from rice fields, to 1-year-old, 4-8-year-old and over 10-year-old pastures planted to {B}rachiaria brizantha. {I}n the early phases of the farming cycle reduction in the average plant total species richness in 50 m 2 plots decreased from 67 to 20 species and comprised both woody and herbaceous species. {T}he increase to 41 species further observed in mature pastures was essentially comprised of herbaceous species. {R}ice fields were characterised by a great floristic heterogeneity which later decreased when they were planted to pastures. {PCA} of plant communities ordinated plots along a gradient of increasing anthropisation that explained 23.6% of total variance. {S}pecies were classified into four ecological groups, which floristic composition and specific richness changed throughout the farming succession. {S}pecies richness and density of forest woody species decreased progressively from 32 to 7 species and from 152 to 16 2 individuals per 50 in, and only a few species such as {M}emora allanmandiflora and {P}oecilanthe effusa resisted pasture conditions. {P}ioneer/ secondary woody species of the genera {C}ecropia and {S}olanum germinated out of the forest seed bank, and seven species on average were observed in rice fields and 1-year-old pastures. {A}t later stages (>4 years) their respective species richness decreased to three species while their density decreased sharply, from 439 to 41 individuals per 50 m(2). {A} few forest herbaceous species of the families {M}arantaceae and {P}oaceae and the fern species {A}diantum argutum, which survived in rice fields (2 species per 50 in 2 on average), almost disappeared in the 4-8-year-old pastures. {I}n the early phase of the intra-farming succession, a rather stable community of six species of secondary herbaceous plants on average was established. {S}pecies richness further increased to 16 in the > 10-year-old pastures with addition of species such as {D}esmodium axillare, {P}hyllanthus amarus or {C}yperus compressus. {I}n accordance with the concept of {I}nitial {F}loristic {C}omposition, floristic composition at the beginning of the intra-farming succession was determined by the floristic composition of the former forest and by the nature and intensity of the initial disturbance (deforestation and burning). {F}urther changes in species richness, floristic composition and density in the intrafarming succession are driven by the intra-farming management.},
  keywords = {amazonia ; agricultural successions ; ecological groups ; pastures ; smallholder farming ; biodiversity},
  booktitle = {},
  journal = {{A}griculture {E}cosystems and {E}nvironment},
  volume = {124},
  numero = {1-2},
  pages = {72--84},
  ISSN = {0167-8809},
  year = {2008},
  DOI = {10.1016/j.agee.2007.07.007},
  URL = {https://www.documentation.ird.fr/hor/fdi:010042495},
}