2 research outputs found
Aporte e decomposiĆ§Ć£o de serapilheira em um fragmento de cerrado sensu stricto
Considering the importance of nutrient cycling as an indicator in the maintenance of
the productivity of the ecosystem, the present study aimed to assess the seasonal
dynamics of production and decomposition rate of litter in a fragment of Cerrado sensu
stricto. For evaluation of supply of burlap were used 50 circular collectors with 112.8
cm diameter, distributed systematically. Litter collections were performed monthly June
2016-may 2017 and the collected material was packed in plastic bags, then taken to
the laboratory where the separation was carried out in fractions leaves, twigs and
reproductive material. After that, the material was packed in paper bags and washed
the greenhouse at the 70 C, for the determination of the dry weight. The decomposition
of leaf litter was evaluated using the method of litter bags, with random distribution of
288 litter bags containing 20 grams of leaves and 24 litter bags containing 20 grams
of branches. The annual production of litterfall was quantified in 6.042,50 kg. ha-1. yr-
1, in which the leaf was prevalent fraction presented a production of 4.644,40 kg. ha-1.
yr-1, then the fractions branches (1.084,10 kg. ha-1. yr-1) and reproductive material
(329,90 kg. ha-1. yr-1). The litterfall obtained higher production in July with 1.464,00 kg.
ha-1 and lower production in the month of December (138,70 kg. ha-1). A significant
negative correlation was observed between litterfall and its fractions with the
precipitation and relative humidity. The decomposition of foliar mass reached 49% and
50% of twigs during the nine-month period, in which the decomposition constant (k) for
leaf mass and for branches was 0.0030 g g-1-1day.For this constant, the estimate for
the disappearance of total mass has been estimated to be 1.000 days (29 months). It
can be concluded that the litterfall presented seasonality well marked, with higher
output during the dry season and lower in the rainy season with strong influence of
precipitation and relative humidity in the deposition of the leaves. The breakdown
proved slow for both leaves as for branches to get the value of the constant of
decomposition 0.0030 g g-1-1 day for both.Considerando a importĆ¢ncia da ciclagem de nutrientes como indicador na manutenĆ§Ć£o
da produtividade do ecossistema, o presente estudo teve como objetivo avaliar a
dinĆ¢mica sazonal de produĆ§Ć£o e taxa de decomposiĆ§Ć£o de serapilheira em um
fragmento de Cerrado sensu stricto. Para avaliaĆ§Ć£o de aporte de serapilheira foram
utilizados 50 coletores circulares com 112,8 cm de diĆ¢metro, distribuĆdos
sistematicamente. As coletas de serapilheira foram realizadas mensalmente de junho
de 2016 a maio 2017 e o material coletado foi acondicionado em sacos plƔsticos,
posteriormente levados para o laboratĆ³rio onde foi realizada a separaĆ§Ć£o nas fraƧƵes
folhas, galhos e material reprodutivo. Posteriormente, o material foi embalado em
sacos de papel e levado Ć estufa Ć temperatura de 70 oC, para a determinaĆ§Ć£o do
peso seco. A decomposiĆ§Ć£o da serapilheira foi avaliada utilizando-se o mĆ©todo de
litter bags, com distribuiĆ§Ć£o aleatĆ³ria de 288 litter bags que continham 20 gramas de
folhas e 24 litter bags que continham 20 gramas de galhos. A produĆ§Ć£o anual de
serapilheira foi quantificada em 6.042,50 kg.ha-1.a-1, em que a fraĆ§Ć£o foliar foi
predominante apresentando uma produĆ§Ć£o de 4.644,40 kg.ha-1.a-1, seguida da fraĆ§Ć£o
galhos (1.084,10 kg.ha-1.a-1) e material reprodutivo (329,90 kg.ha-1.a-1). A produĆ§Ć£o de
serapilheira obteve maior produĆ§Ć£o no mĆŖs de julho com 1.464,00 kg.ha-1 e menor
produĆ§Ć£o no mĆŖs de dezembro (138,70 kg.ha-1). Foi observada correlaĆ§Ć£o negativa
significativa entre a produĆ§Ć£o de serapilheira e suas fraƧƵes com a precipitaĆ§Ć£o
pluviomĆ©trica e umidade relativa do ar. A decomposiĆ§Ć£o da massa foliar atingiu 49%
e a de galhos 50%, durante o perĆodo de nove meses, em que a constante de
decomposiĆ§Ć£o (k) para massa foliar e para galhos foi de 0,0030 g g-1dia-1. Por esta
constante, a estimativa para o desaparecimento de massa total foi estimada em 1.000
dias (29 meses). Ć possĆvel concluir que a produĆ§Ć£o de serapilheira apresentou
sazonalidade bem marcada, com maior produĆ§Ć£o durante a Ć©poca seca e menor na
Ć©poca chuvosa, com forte influĆŖncia de precipitaĆ§Ć£o e umidade relativa do ar na
deposiĆ§Ć£o das folhas. A decomposiĆ§Ć£o se mostrou lenta tanto para folhas como para
galhos obtendo assim o valor da constante de decomposiĆ§Ć£o 0,0030 g g-1dia-1 para
ambos
SUPPLYING AND DECOMPOSITION OF BURLAP IN A FRAGMENT OF CERRADO SENSU STRICTO
Considering the importance of nutrient cycling as an indicator in the maintenance of the ecosystem productivity, the present study aimed to assess the seasonal dynamics of production and decomposition rate of litter in a fragment of Cerrado sensu stricto. The litter collections were carried out monthly from june 2016 to may 2017, after which the leaves, branches and reproductive material were separated. The litter decomposition was evaluated using the litter bags method, with a random distribution of 288 litter bags. The annual production of litterfall was quantified in 6.042,50 kg.ha-1.yr-1, in which the leaf prevalent fraction presented a production of 4.644,40 kg.ha-1.yr-1, then, the fractions branches (1.084,10 kg.ha-1.yr-1) and reproductive material (329,90 kg.ha-1.yr-1). The litterfall obtained higher production in july with 1.464,00 kg.ha-1 and lower production in the month of December (138,70 kg.ha-1). A significant negative correlation was observed between litterfall and its fractions with the precipitation and relative humidity. The decomposition of foliar mass reached 49% and 50% of twigs during the nine-month period, in which the decomposition constant (k) for leaf mass and for branches was 0.0030g g-1day-1. For this constant, the estimate for the disappearance of total mass has been estimated to be 1.000 days (29 months). The breakdown proved to be slow for both leaves and branches thus obtaining the value of the constant of decomposition 0.0030g g-1 day-1for both