Potential for nutrient contribution from litter in a seasonally dry forest

Litter is the most important way of transferring essential elements from vegetation to the soil. This is due to nutrient cycling, a process by which decomposition of the litter adds nutrients to the soil. An understanding of this process goes beyond the need for knowledge of nutrient dynamics, since it is a question of understanding the way in which ecosystems function in the search for a correct use of natural resources. The aim of this study was to quantify the average concentrations of the following nutrients: Nitrogen (N), phosphorus (P), Potassium (K), and Organic Carbon (C) in litter remaining in an area of tropical dry forest - Caatinga. The work was carried out on the Elias Andrade Private Natural Heritage Reserve (PNHR) of the Irmãos Andrade Farm, located in the semi-arid region of the State of Ceará. In February 2009, 48 nylon litter bags were randomly distributed, each containing 30 g of litter collected in the area of the Reserve. Every two months, from February 2009 to January 2011, four bags were randomly collected. Over time, variations were seen in the average levels of N, P and K for the litter in the nylon bags. The nutrient with the greatest contribution to the system from the litter was Nitrogen, followed by K and P. The highest N content occurred at the beginning of the experiment. The C content decreased over the study period. The mean C to N ratio of the litter was 21, which was in the borderline range between the processes of mineralisation and immobilisation.Litter is the most important way of transferring essential elements from vegetation to the soil. This is due to nutrient cycling, a process by which decomposition of the litter adds nutrients to the soil. An understanding of this process goes beyond the need for knowledge of nutrient dynamics, since it is a question of understanding the way in which ecosystems function in the search for a correct use of natural resources. The aim of this study was to quantify the average concentrations of the following nutrients: Nitrogen (N), phosphorus (P), Potassium (K), and Organic Carbon (C) in litter remaining in an area of tropical dry forest - Caatinga. The work was carried out on the Elias Andrade Private Natural Heritage Reserve (PNHR) of the Irmãos Andrade Farm, located in the semi-arid region of the State of Ceará. In February 2009, 48 nylon litter bags were randomly distributed, each containing 30 g of litter collected in the area of the Reserve. Every two months, from February 2009 to January 2011, four bags were randomly collected. Over time, variations were seen in the average levels of N, P and K for the litter in the nylon bags. The nutrient with the greatest contribution to the system from the litter was Nitrogen, followed by K and P. The highest N content occurred at the beginning of the experiment. The C content decreased over the study period. The mean C to N ratio of the litter was 21, which was in the borderline range between the processes of mineralisation and immobilisation

Deposição e decomposição de serapilheira em área da Caatinga

Para avaliar a deposição e a taxa de decomposição da serapilheira em área da Caatinga, bem como, verificar a interferência de variáveis climáticas, desenvolveu-se um estudo em quatro microbacias localizadas no município de Iguatu, Ceará, Brasil. A produção de serapilheira era coletada mensalmente (mai/2007 a set/2008) em 20 caixas de 1,0 m2, separando-se em seguida as frações: folhas, estruturas reprodutivas, galhos e miscelânea. Coletou-se, trimestralmente, a serapilheira circunscrita sob um quadrado de ferro de (0,5 m x 0,5 m), estimando-se em seguida a serapilheira armazenada sobre o solo; a massa seca de serapilheira foi obtida pela secagem em estufa a 70ºC até peso constante. Foram coletadas amostras de solo (0-15 cm) para se obter a umidade. Observou-se que entre as espécies arbustivo-arbóreas, apenas duas (Aspidosperma pyrifolium Mart. e Croton sonderianus Muell. Arg.) representam mais de 50% da população e a cobertura vegetal é determinada pelo estrato herbáceo, já que apresenta um número bem maior de plantas. A produção de folhas apresentou uma estreita relação com o regime pluviométrico, sendo seu ápice logo após a quadra chuvosa, enquanto a produção de estruturas reprodutivas foi determinada pelas espécies. A deposição da serapilheira apresentou caráter sazonal com uma produtividade de 2.855,42 kg ha-1, e picos de produção imediatamente posterior a quadra chuvosa. Já a decomposição da serapilheira mostrou-se relativamente lenta, com uma taxa de decomposição (K) inferior a 1

Potential for nutrient contribution from litter in a seasonally dry forest

Litter is the most important way of transferring essential elements from vegetation to the soil. This is due to nutrient cycling, a process by which decomposition of the litter adds nutrients to the soil. An understanding of this process goes beyond the need for knowledge of nutrient dynamics, since it is a question of understanding the way in which ecosystems function in the search for a correct use of natural resources. The aim of this study was to quantify the average concentrations of the following nutrients: Nitrogen (N), phosphorus (P), Potassium (K), and Organic Carbon (C) in litter remaining in an area of tropical dry forest - Caatinga. The work was carried out on the Elias Andrade Private Natural Heritage Reserve (PNHR) of the Irmãos Andrade Farm, located in the semi-arid region of the State of Ceará. In February 2009, 48 nylon litter bags were randomly distributed, each containing 30 g of litter collected in the area of the Reserve. Every two months, from February 2009 to January 2011, four bags were randomly collected. Over time, variations were seen in the average levels of N, P and K for the litter in the nylon bags. The nutrient with the greatest contribution to the system from the litter was Nitrogen, followed by K and P. The highest N content occurred at the beginning of the experiment. The C content decreased over the study period. The mean C to N ratio of the litter was 21, which was in the borderline range between the processes of mineralisation and immobilisation.Litter is the most important way of transferring essential elements from vegetation to the soil. This is due to nutrient cycling, a process by which decomposition of the litter adds nutrients to the soil. An understanding of this process goes beyond the need for knowledge of nutrient dynamics, since it is a question of understanding the way in which ecosystems function in the search for a correct use of natural resources. The aim of this study was to quantify the average concentrations of the following nutrients: Nitrogen (N), phosphorus (P), Potassium (K), and Organic Carbon (C) in litter remaining in an area of tropical dry forest - Caatinga. The work was carried out on the Elias Andrade Private Natural Heritage Reserve (PNHR) of the Irmãos Andrade Farm, located in the semi-arid region of the State of Ceará. In February 2009, 48 nylon litter bags were randomly distributed, each containing 30 g of litter collected in the area of the Reserve. Every two months, from February 2009 to January 2011, four bags were randomly collected. Over time, variations were seen in the average levels of N, P and K for the litter in the nylon bags. The nutrient with the greatest contribution to the system from the litter was Nitrogen, followed by K and P. The highest N content occurred at the beginning of the experiment. The C content decreased over the study period. The mean C to N ratio of the litter was 21, which was in the borderline range between the processes of mineralisation and immobilisation

Deposição e decomposição de serapilheira em área da Caatinga

Para avaliar a deposição e a taxa de decomposição da serapilheira em área da Caatinga, bem como, verificar a interferência de variáveis climáticas, desenvolveu-se um estudo em quatro microbacias localizadas no município de Iguatu, Ceará, Brasil. A produção de serapilheira era coletada mensalmente (mai/2007 a set/2008) em 20 caixas de 1,0 m2, separando-se em seguida as frações: folhas, estruturas reprodutivas, galhos e miscelânea. Coletou-se, trimestralmente, a serapilheira circunscrita sob um quadrado de ferro de (0,5 m x 0,5 m), estimando-se em seguida a serapilheira armazenada sobre o solo; a massa seca de serapilheira foi obtida pela secagem em estufa a 70ºC até peso constante. Foram coletadas amostras de solo (0-15 cm) para se obter a umidade. Observou-se que entre as espécies arbustivo-arbóreas, apenas duas (Aspidosperma pyrifolium Mart. e Croton sonderianus Muell. Arg.) representam mais de 50% da população e a cobertura vegetal é determinada pelo estrato herbáceo, já que apresenta um número bem maior de plantas. A produção de folhas apresentou uma estreita relação com o regime pluviométrico, sendo seu ápice logo após a quadra chuvosa, enquanto a produção de estruturas reprodutivas foi determinada pelas espécies. A deposição da serapilheira apresentou caráter sazonal com uma produtividade de 2.855,42 kg ha-1, e picos de produção imediatamente posterior a quadra chuvosa. Já a decomposição da serapilheira mostrou-se relativamente lenta, com uma taxa de decomposição (K) inferior a 1