SALINIDADE DA ÁGUA, FONTES DE NITROGÊNIO E BIOFERTILIZANTE BOVINO, NA FORMAÇÃO DE MUDAS DE JACA MOLE

The jackfruit is an exotic, species from India and introduced in Brazil during the colonial period. Scientific information about their responses to salinity are still uncommon in the Brazilian and world literature. In this sense, the objective of this study was to evaluate the effects of electrical conductivity of irrigation water, nitrogen fertilizer and application of liquid cattle manure fermented in the formation of Artocarpus heterophyllus Lam seedlings diversity mole. The work was carried out on the screened greenhouse Universidade Federal da Paraíba, Areia county, Paraíba State, Brazil and treatments were arranged in a randomized block design using the factorial 5 x 3 x 2, corresponding to the levels of electrical conductivity of irrigation water (0.3; 1.0; 2.0; 3.0 and 4.0 dS m-1), nitrogen fertilization regarding absence and 150 mg dm-3 nitrogen in form of ammonia sulphate and urea in soil with and without fermented liquid bovine manure or bovine common biofertilizer on the substrate surface on the day of sowing and 30 days after seedling emergence. The variables analyzed were: electrical conductivity of aqueous extract 1:1 hydrogen potential (soil suspension/water), stem diameter, plant height, leaf number, leaf area, specific leaf area, leaf area ratio, dry mass of root, shoot and total dry matter, Dickson quality index and indices of chlorophyll a, b and total at 85 days after sowing. Increasing the salt concentration of irrigation water increased the salinity of the substrate and compromised biometric growth, biomass production and capacity clorofilática jacketA jaca é uma espécie exótica, originária da Índia e introduzida no Brasil durante o período colonial. As informações científicas a respeito de suas respostas à salinidade são ainda pouco frequentes na literatura brasileira e mundial. Nesse sentido, o objetivo do trabalho foi avaliar os efeitos da condutividade elétrica da água de irrigação, adubação de nitrogênio e aplicação de esterco líquido fermentado de bovino na formação de mudas de Artocarpus heterophyllus Lam. variedade mole. O trabalho foi desenvolvido na estufa telada da Universidade Federal da Paraíba, Areia, Paraíba, Brasil e os tratamentos foram distribuídos em blocos casualizados usando o arranjo fatorial 5 x 3 x 2, correspondente aos níveis de condutividade elétrica da água de irrigação (0,3; 1,0; 2,0; 3,0 e 4,0 dS m-1), adubação nitrogenada referente a ausência e 150 mg dm-3 de nitrogênio na forma de sulfato de amônia e ureia no solo sem e com esterco líquido fermentado de bovino ou biofertilizante bovino comum aplicado na superfície do substrato no dia da semeadura e aos 30 dias após a emergência das plântulas. As variáveis analisadas foram: condutividade elétrica do extrato aquoso na proporção de 1:1 (suspensão solo/água), potencial hidrogeniônico, diâmetro do caule, altura das plantas, número de folhas, área foliar, área foliar específica, razão de área foliar, massa da matéria seca de raiz, da parte aérea e matéria seca total, índice de qualidade de Dickson e índices de clorofila a, b e total, aos 85 dias após a semeadura. O aumento da concentração salina das águas de irrigação elevou a salinidade do substrato e comprometeu o crescimento biométrico, a produção de biomassa e a capacidade clorofilática da jaqueira

ENVIRONMENTAL DEGRADATION AND RISK OF DESERTIFICATION IN ALTO SERTÃO REGION, ALAGOAS STATE, BRAZIL

In this research, the authors evaluated the degree of degradation of the Caatinga biome in Sertão do São Francisco Microregion, Alagoas State, Brazil, by the association of these results with the aridity. We obtained a panorama of the desertification propensity in this area. From the aridity index (IA), the region was classified as having a semi-arid condition (0.2 ? IA <0.5). It was observed values of IA less than 0.50, characterizing an environment with high propensity to establish the state of desertification. From the collected data, we realized the state of degradation of the municipalities in study, all with percentage of anthropic areas greater than 60%. The municipality of Piranhas deserves highlight by the analysis of temporal evolution of the anthropized Caatinga area, with an increase of 44, 661 km² between 2002 and 2009, corresponding to an increase of 17.8% in only seven years. It leads to a scenario where 74.21% of the original Caatinga is in an anthropized state. The critical values of the aridity index, associated to high degree of anthropization may lead to the establishment of desertification process in the study area

Isolated and combined effects of soil salinity and waterlogging in seedlings of ‘Green Dwarf’ coconut

Soil salinization is a problem commonly found in semi-arid regions. In addition, the problem of salinity is aggravated in clayey soils when accompanied by cycles of waterlogging in the rainy season or when excess irrigation is applied. In this work we evaluated the isolated and combined effects of soil salinity and waterlogging on the responses of young plants of ‘Green Dwarf’ coconut. The experiment was conducted under controlled environment in a complete randomized block design, arranged in split plots with five replications. The plots comprised five waterlogging cycles (0, 1, 2, 3 and 4), each with a duration of four days, and applied at 30, 60, 90 and 120 days into the experimental period, with the sub-plots consisting of five levels of soil salinity (1.70, 11.07, 16.44, 22.14 and 25.20 dS m-1). Response of coconut seedlings to waterlogging was dependent on the level of soil salinity, with waterlogging significantly impairing biomass accumulation and leaf expansion at low soil salinity levels, but causing no additional harm at elevated salinity. Leaf gas exchange was reduced mainly due to soil salinity, and this response was related to stomatal and non-stomatal effects. Seedlings of ‘Green Dwarf’ coconut used in this study were classified as moderately-tolerant to salinity when grown in soils with an electrical conductivity up to 11.07 dS m-1, having the potential to be used in revegetation programs of salt-affected areas, provided that these areas are not exposed to frequent waterlogging cycles

Biomass and chloroplast pigments in jackfruit seedlings under saline stress and nitrogen fertilization

Irrigation with saline water is a worldwide necessity an excess of salts in water or in soil causes growth inhibition, and negatively affects the productivity of many crops. Application of nitrogen fertilizers may be a way of mitigating the effects of salts on plants. The aim of this study was to evaluate the accumulation of biomass and the chlorophyll pigment content in jackfruit seedlings irrigated with water of increasing salinity level in soil with nitrogen sources. The treatments were distributed in randomized blocks with four replicates and three plants per plot, arranged in a 5 × 3 factorial scheme, related to electrical conductivity levels of the irrigation water of 0.3, 1.0, 2.0, 3.0 and 4.0 dS m −1 , in soil without nitrogen, with ammonium sulfate and with urea, in a split application 60 and 75 days after sowing. An increase in the salinity of the water increased the salinity levels of soil, which was intensified by a dose of 150 mg of N, mainly when applied in the form of ammonium sulfate, inhibiting dry matter production and chlorophyll content in jackfruit seedlings. The greatest reductions in chlorophyll a and b content occurred in jackfruit seedlings irrigated with water of 4.0 dS m −1 conductivity in the soil without nitrogen fertilization. Urea is the most suitable nitrogen source for the production of seedlings under conditions of high salinity.A irrigação com água salina é uma necessidade mundial e o excesso de sais da água ou do solo, causa inibição no crescimento e no rendimento da grande maioria das plantas cultivadas. Nesse contexto, os fertilizantes nitrogenados podem constituir alternativa para a mitigação dos efeitos dos sais sobre as plantas. Com isso, objetivou-se avaliar o acúmulo de biomassa e o índice de pigmentos clorofiláticos em mudas de jaqueira irrigadas com água de salinidades crescentes no solo com fontes de nitrogênio. Os tratamentos foram distribuídos em blocos casualizados com quatro repetições e com três plantas por parcela, arranjados em fatorial 5 × 3, relativo aos níveis de condutividade elétrica da água de irrigação de 0,3; 1,0; 2,0; 3,0 e 4,0 dS m –1 , no solo sem nitrogênio, com sulfato de amônio e com ureia aplicados parceladamente aos 60 e 75 dias após a semeadura. O aumento da salinidade da água elevou a salinidade do solo, a qual foi intensificada pela dose de 150 mg de N, principalmente quando aplicada na forma de sulfato de amônio, ao ponto de inibir a formação de massa da matéria seca e os teores de clorofila em mudas de jaqueira. As maiores reduções no índice de clorofila a e b foram nas mudas de jaqueira irrigadas com água de 4,0 dS m –1 no solo sem adubação nitrogenada. A ureia é a fonte nitrogenada mais indicada para produção de mudas em condições de elevada salinidade

Quality of jackfruit seedlings under saline water stress and nitrogen fertilisation

The lack of good quality water for agriculture purposes regarding salts and quantity in relation to demand for the plants has, for more than 30 years, been forcing the use of restrictive water because of salinity issues in agricultural production systems worldwide. In Brazil, the situation is no different, in the semi-arid areas, there are reports of losses of seed germination, initial growth of seedlings and yield of crops of commercial importance due to the salinity of the water used in irrigation systems. Therefore, an experiment was carried out from June to September/2014 in a protected environment, with a plastic film on the upper base and a thin screen against insects on the sides, to evaluate the effects of salinity interaction between water irrigation and nitrogen fertilisation sources on soil salinity, initial plant growth and the quality of the jackfruit seedlings. The treatments were distributed in randomised blocks, in the factorial scheme 5 × 3, reference irrigation water of 0.3, 1.0, 2.0, 3.0 and 4.0 dS m-1, in soil with and without ammonium sulfate and urea. An increase in the salinity of the irrigation water to 1.32 and 1.70 dS m-1 on the substrate without nitrogen stimulated an increase in the number of leaves and leaf area of the jackfruit seedlings. The ammonium sulfate was the nitrogen source that mainly contributed to the increase of soil salinity and to the reduction of the quality index of the seedlings. Despite the reduction of the Dickson quality index due to the salinity of the irrigation water and the nitrogen sources, the seedlings were suitable for cultivation

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved