Hydroretent polymers in the production and planting of Enterolobium contortisiliquum (Vell.) Morong and Paubrasilia echinata Lam
| Autor: | Almeida, Caroline de Melo |
|---|---|
| Přispěvatelé: | Arthur Junior, Jose Carlos, Arthur Junior, Jos? Carlos, Carvalho, Daniel Fonseca de, Silva, Magali Ribeiro da |
| Jazyk: | portugalština |
| Rok vydání: | 2021 |
| Předmět: | |
| Zdroj: | Biblioteca Digital de Teses e Dissertações da UFRRJ Universidade Federal Rural do Rio de Janeiro (UFRRJ) instacron:UFRRJ |
| Popis: | Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2022-05-06T20:02:41Z No. of bitstreams: 1 2021 - Caroline de Melo Almeida.pdf: 2041175 bytes, checksum: 1e0a2ce652d351843ba831cc34a18457 (MD5) Made available in DSpace on 2022-05-06T20:02:41Z (GMT). No. of bitstreams: 1 2021 - Caroline de Melo Almeida.pdf: 2041175 bytes, checksum: 1e0a2ce652d351843ba831cc34a18457 (MD5) Previous issue date: 2021-05-31 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior Agriculture is the activity that most demands fresh water from the planet, largely due to its inefficient use during the irrigation process, generating great waste. In forest nurseries, irrigation is performed in an empirical way, causing significant waste. Hydroretentive polymers have the potential to reduce the amount of water used in irrigation, but there is a lack of studies in the production of forest species, besides the variation in characteristics of the commercial products available. The study aimed to evaluate the use of water-retaining polymers in the production and planting of seedlings of Enterolobium contortisiliquum and Paubrasilia echinata, analyzing morphological characteristics and survival. The water uptake of three water-retaining polymers: Hydroplan?, Forth? and UPDT? was also evaluated, as well as the effect of the electrical conductivity of water with potassium chloride and calcium chloride salts on their uptake, and the influence of polymers on the physical properties of the substrate. Adopting an entirely randomized design, three independent experiments were conducted aiming at seedling production, using three doses of the hydroretentative polymer Hydroplan? (2,0; 4,0 and 6,0 g L-1) added to the commercial substrate MecPlant?, plus a treatment without the presence of the polymer, in 280 cm? tubes. To quantify the volume of water applied, a low cost semi-automated drip irrigation system was used. The seedlings were planted in pots, simulating field conditions. A 4x4 factorial scheme was used, with factor 1 being the seedlings produced in the previous treatments and factor 2 the application of polymers at planting (0; 1,5; 3,0 and 6,0 g planting hole-1) in an entirely randomized design. The polymers Hydroplan? and Forth? had a higher water absorption capacity between 349 and 374 g of water per g of product, than the plant-based polymer (78 g). A significant reduction in water absorption was observed as a function of increasing electrical conductivity of the water. Even at a lower conductivity, 1,0 dS m-1, the reduction was approximately 50% of the water uptake capacity, calcium chloride being more harmful than potassium chloride. No changes occurred in the physical properties of the substrate with the addition of the hydroretentive polymer. Considering the morphological variables, in general, Enterolobium contortisiliquum seedlings had similar growth and quality among treatments. For Paubrasilia echinata seedlings, a negative effect was observed for some variables with higher polymer doses, but with no difference in quality. Due to the absorption capacity and gradual release of water from the hydroretentive polymer, the reduction was 51,6% and 42,9% of water consumption for the species Enterolobium contortisiliquum and Paubrasilia echinata, respectively, in the treatment of 6,0 g L-1 compared to the treatment without addition of the polymer. There was increased survival of seedlings produced with increasing doses of hydroretentive polymer in pots, even at lower doses, on average 59 versus 41 days. A agricultura ? a atividade que mais demanda ?gua doce do planeta, muito em fun??o do seu uso ineficiente durante o processo de irriga??o, gerando grandes desperd?cios. Nos viveiros florestais, a irriga??o ? realizada de forma emp?rica, acarretando desperd?cios significativos. Os pol?meros hidrorretentores tem potencial para reduzir a quantidade de ?gua utilizada na irriga??o, mas h? car?ncia de estudos na produ??o de esp?cies florestais, al?m da varia??o de caracter?sticas dos produtos comerciais dispon?veis. O estudo teve como objetivo avaliar a utiliza??o de pol?meros hidrorretentores na produ??o e no plantio de mudas das esp?cies florestais Enterolobium contortisiliquum e Paubrasilia echinata, analisando-se caracter?sticas morfol?gicas e de sobreviv?ncia. Avaliou-se tamb?m a absor??o de ?gua de tr?s pol?meros hidrorretentores: Hydroplan?, Forth? e UPDT?, bem como o efeito da condutividade el?trica da ?gua com sais de cloreto de pot?ssio e de cloreto de c?lcio na sua absor??o, e a influ?ncia dos pol?meros nas propriedades f?sicas do substrato. Adotando delineamento inteiramente casualizado, foram conduzidos 2 experimentos independentes visando ? produ??o das mudas, utilizando 3 doses do pol?mero hidrorretentor Hydroplan? (2,0; 4,0 e 6,0 g L-1) adicionadas ao substrato comercial MecPlant?, mais o tratamento sem a presen?a do pol?mero, em tubetes de 280 cm?. Para quantificar o volume de ?gua aplicado, utilizou-se sistema semiautomatizado de irriga??o de baixo custo por gotejamento. As mudas foram plantadas em vaso, simulando condi??es de campo. Foi utilizado um esquema fatorial 4x4, sendo o fator 1 as mudas produzidas nos tratamentos anteriores e o 2 a aplica??o de pol?meros no plantio (0; 1,5; 3,0 e 6,0 g cova-1) em delineamento inteiramente casualizado. Os pol?meros Hydroplan? e Forth? tiveram maior capacidade de absor??o de ?gua entre 349 e 374 g de ?gua por g de produto, do que o pol?mero ? base vegetal (78 g). Observou-se redu??o significativa da absor??o de ?gua em fun??o do aumento da condutividade el?trica da ?gua. Mesmo numa condutividade menor, de 1,0 dS m-1, a redu??o foi de aproximadamente 50% da capacidade de absor??o de ?gua, sendo o cloreto de c?lcio mais prejudicial do que o cloreto de pot?ssio. N?o ocorreu mudan?as nas propriedades f?sicas do substrato com adi??o do pol?mero hidrorretentor. Considerando as vari?veis morfol?gicas, de forma geral, as mudas de Enterolobium contortisiliquum tiveram crescimento e qualidade semelhantes entre os tratamentos. Para as mudas de Paubrasilia echinata observou-se efeito negativo para algumas vari?veis com doses maiores de pol?mero, por?m sem diferen?a para qualidade. Em fun??o da capacidade de absor??o e de libera??o gradual de ?gua do pol?mero hidrorretentor, a redu??o foi de 51,6% e 42,9% do consumo de ?gua para as esp?cies Enterolobium contortisiliquum e Paubrasilia echinata, respectivamente, no tratamento de 6,0 g L-1 comparado ao tratamento sem adi??o do pol?mero. Houve aumento da sobreviv?ncia das mudas produzidas com doses crescentes de pol?mero hidrorretentor em vaso, mesmo em menores doses, em m?dia de 59 contra 41 dias. |
| Databáze: | OpenAIRE |
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