Lâminas de água salina e doses de adubação orgânica na produção de palma Miúda adensada no semiárido

Cactus pear is an important forage for livestock in semi-arid region of Brazil, due to its adaptation to climate conditions in this region, high productivity and nutritional value. The yield of this cactus has positively responded to techniques such as planting density, fertilization and cutting managements, however, in Rio Grande do Norte State, only certain areas have favorable climate conditions to the development of this crop. Drip irrigation, with a small amount of water, has proven to be an alternative to the viability of cactus pear cultivation in these areas. The research aimed to evaluate the effects of different levels of saline water and manure organic fertilization on the morphological characteristics and production of fresh and dry matter of the prickly-pear cactus cv. Miúda (Nopalea cochenillifera Salm Dick) in a dense planting system. The experiment was conducted at the Experimental Station of Terras Secas (EMPARN), Pedro Avelino, latitude 5°31'21" South and longitude 36°23'14" West. The soil was classified as Typical Cambisol Haplicum Carbonate and the water used in irrigation, C4S1T3 (5,25 dS.m-1), with planting spacing of 2.0 x 0.25 m (20,000 plants ha-1). A completely randomized design in a split plot was used, where water levels (0, 7.5, 15.0 and 30.0 mm month-1) with 10 days intervals, were the main plots and organic fertilization (0 , 25 and 50 Mg ha-1 yr-1) the subplots, with four replicates. The measured morphological characteristics were number of cladodes, height and volume of the plant; length, width, perimeter, thickness, area and cladodes area index, fresh and dry matter production, dry matter content, water use efficiency (WUE) and damage promoted by cochineal pest (Diaspis echinocacti) and soft rot (Erwinia carotovora). There was no influence (P>0.05) of organic fertilization on most variables, particularly in relation to the production of fresh and dry matter. The water levels had a significant influence (P<0.05) on most variables, promoting higher height and volume of the plants, larger and thicker cladodes, and increase on fresh and dry matter production (13.55 Mg DM ha-1 yr-1). The absence of irrigation caused a significant expansion in plant damage caused by the cochineal pest and when irrigated with different water levels there was an increase in damage and stand loss, caused by soft rot, been more intense at the higher water level.

O princípio constitucional da eficiência aplicado à outorga e à cobrança da água produzida na exploração petrolífera

Water production is unavoidable during a petrol well s lifetime. The amount of produced water associated with oil varies a lot. It can reach values which account to 50% in volume up to nearly 100%, at the end of the well s economic life. It could be verified that, once the water reaches the productive wells, there must be a management of this produced water. Its destiny is defined after a precise study, after which the best option is chosen between relieving it into the environment, re-injecting it into the producing container or disposing it into non-producing formations. Whichever option is made by the involved professionals, after the necessary analysis, it shall consider, besides the technical and economical aspects, also the alternatives which entail less environmental impact. The purpose of the present research is to conduct a study about the application of the constitutional principle of efficiency on the instruments worked out by the public administration on water management, specifically the water use licence and charging for the use in the management of water resources applicable to water production at the petrol wells. In this attempt, before entering the proper approach of the efficiency of the mentioned instruments, it was necessary not only bring to light the doctrinal perception about the constitutional principle of administrative efficiency, but also make some considerations concerning to the structure of the national water resources management, set by the Federal Constitution (1988) and the federal legislation (9433/97)

Uso urbano não potável de água de lagoas do sistema de drenagem de Natal

The detention and infiltration ponds of urban drainage system has function to protect the population from undesirable effects of floods. In general these ponds are not completly used and it potential is wasted. As it are disseminated at different places at cities it can reduce costs with water transport and permit water preservation of best quality. Some it utilities includes use in green areas irrigation, industrial among than cooling towers and boiler, soil compaction, cleaning urban road, pisciculture and fire fighting system. The quality these water is influenced by anauthorized sewage in the drainage system. This study was performed in six detention and infiltration ponds at drainage system of Natal, which aim was to verify the non-portable use these ponds on urban environment. As indirect aim would to incentive the water utilization these ponds as a water source to another uses in urban environment. These ponds represents the characteristics of detention and infiltration of Natal city and consequently of Brazil. As the water quality, the ponds presents following characteristics: three has apparently good quality, other showed intermediate condition and two had water polluted. Were performed twenty sample in each ponds and the following parameters assessed: pH, temperature, dissolved oxygen, turbidity, electrical conductivity, coliform thermotolerant, ammonia, organic nitrogen, TKN, nitrate, total phosphorus and alkalinity, bicarbonate, chloride, total hardness, calcium and magnesium hardness, total solids, TSS, TDS, COD and SAR°. To utilization on pisciculture we recommend use in ponds which presents the best quality. Only one pond presented higher pollutants and it not being appropriated for use in cooling tower. The content of solids suspension restricted the water use in all ponds in boilers. As water use in soil compaction, cleaning urban road and fire fighting system the water from these ponds are not appropriated. However, the recommended limits from literature are to domestic sewage, due to this, the parameters are restrictive to diminish the sanitary risk that could be offered with it utilization. The infiltration velocity of water these assessed ponds restrict a moderato use, however the effects are potentiated only in soil less sandy, which not occur in Natal. It is recommend the unrestricted irrigation utilization in ponds with best quality of water, and a restricted irrigation to ponds with worst quality of water. As load of pollutants, it is recommended a complementary treatment in those ponds whit higher load to diminish sanitary risks. In only one pond was found one helminth eggs and due to the convention formula of results, it was found for all ponds less than 1 helminth/liter eggs.

Remoção biológica de nitrato em água de abastecimento humano utilizando o endocarpo de coco como fonte de carbono

The groundwater quality has been compromised as a result of the intensification of human activities over the years. Groundwater contamination by nitrate is one of the effects of this degradation, a socio-environmental problem that affects many regions of the world and particular the city of Natal (RN). Developing techniques for nitrate removal in water is intended to eliminate or reduce the concentration of this compound, and those that involve biological processes have produced economic and environmental advantages. This study proposes a technology for biological removal of nitrate in water supply for humans, using the endocarp s coconut as a carbon source and bacteria support. The experiments were performed in pilot scale anoxic, testing different areas of the substrate surface. Results showed high rates nitrate removal during the monitoring period, noting the occurrence of denitrification after the beginning of system operation. The best performance was achieved in the treatment system containing substrate surface area increased, indicating that the decrease in the endocarp size contributed to increased bacterial activity, improving the ability to remove nitrate. About the quality analyzed aspects of water, it was found that the proposed technology has the potential water use for human consumption

Otimização do Uso das Águas da Barragem Santa Cruz-RN

The semiarid potiguar presents a quite discrepant. It is a region with one of the highest rates of artificial lake the world, but the policy of building dams to mitigate the problem of water scarcity does not solve, given that they have not demonstrated the ability to ensure supply human priority during periods of great drought and fail to solve the widespread demand existent in the semiarid. This work aims to present the optimal allocation of water, according to multiple uses and limited availability of water resources in the reservoir, from the simulation of the operation of the same, with the application of techniques to support decision making and performance evaluation alternatives for water use. The reservoir of Santa Cruz, the second largest reservoir of RN with storage capacity of approximately 600 million cubic meters, located about 20 km from the town of Apodi in RN, was conceived as a way to promote economic development in the region as well as the water supply of nearby towns. The techniques used are the simulation model of network flow ACQUANET and also the set of performance indicators. The results showed that the container has the capacity to serve up to 3,83m3/s flow required by existing uses, without any compromising the same. However, it was also observed that all anticipated future demands are implemented it will generate failures in meeting some uses

A água nossa de cada dia : percepção, uso e predisposições comportamentais de alunos do ensino médio de Natal, Rio Grande do Norte

Embora a escassez de água seja reconhecida como um dos principais problemas mundiais a ser enfrentado pela humanidade, padrões comportamentais ecologicamente insustentáveis ainda persistem. Assim, o objetivo deste estudo foi analisar determinantes do comportamento pró-ambiental relativo à água, bem como os significados que lhe são atribuídos por alunos do ensino médio do Centro Federal de Educação Tecnológica do Rio Grande do Norte, em Natal. Compuseram a amostra de conveniência 315 estudantes, 146 mulheres e 169 homens, que responderam a um questionário sobre uso e percepção da água, contendo também indicadores de pró-ambientalismo, cuidado ambiental, desenvolvimento sustentável, perspectiva temporal, externalidades e coletivismo, além de inquérito sócio-demográfico. Para os participantes, água é sinônimo de vida, muito embora a relação que mantém com ela parece dúbia e, muito mais funcional que ecológica; consideram-na um recurso finito, um patrimônio indispensável à vida, contudo não foi observada coerência entre as concepções manifestadas e os comportamentos auto-relatados de uso da água. Os resultados encontrados apontaram preditores importantes do comportamento pró-ambiental relativo à água: sexo do respondente, Escala Novo Paradigma Ecológico e deixar forma de contato para participar de campanhas futuras. Seja para aprofundamento teórico em novos estudos, seja para auxiliar na elaboração de programas de educação ambiental, que poderiam contribuir para inibir os efeitos de uma cultura de consumo e de uma visão utilitarista da água, ampliando esforços individuais e coletivos para a preservação de bens comuns, como a água. Palavras-chave: psicologia ambiental; sustentabilidade; água; comportamento próambiental. x xi Abstract Although water scarcity is recognized as one of the main world-wide problems to be faced by human kind, ecologically unsustainable patterns of behavior still persist. Thus, the objective of this study was to analyze pro-environmental behavior related to water, as well as meanings associated to it by high school students of Federal Center of Technological Education of Rio Grande do Norte, in Natal. The convenience sample was composed by 315 students, 146 women and 169 men, who answered a questionnaire about use and perception of water, containing indicators of proenvironmentalism, environmental care, sustainable development, time perspective, externalities and collectivism, besides socio-demographic items. According to participants, water is synonymous of life, even though the relationship they present with it is ambiguous, much more functional than ecological; they consider it a finite resource, an indispensable life patrimony, however there was no coherence between such conceptions and the self-reported behaviors of water use. Results indicated three important predictors of pro-environmental behavior: sex of respondent, New Ecological Paradigm Scale and telephone/address left for eventual contact to participate in future environmental campaigns. They may be used in additional studies for theoretical development, or to assist in the planning of programs of environmental education, aimed at the inhibition of the effects of a culture of consumption and of an utilitarian perception of water, extending individual and collective efforts towards the preservation of common resources as water

A Água nossa de cada dia: percepção, uso e predisposições comportamentais de alunos do ensino médio de Natal, Rio Grande do Norte

Although water scarcity is recognized as one of the main world-wide problems to be faced by human kind, ecologically unsustainable patterns of behavior still persist. Thus, the objective of this study was to analyze pro-environmental behavior related to water, as well as meanings associated to it by high school students of Federal Center of Technological Education of Rio Grande do Norte, in Natal. The convenience sample was composed by 315 students, 146 women and 169 men, who answered a questionnaire about use and perception of water, containing indicators of proenvironmentalism, environmental care, sustainable development, time perspective, externalities and collectivism, besides socio-demographic items. According to participants, water is synonymous of life, even though the relationship they present with it is ambiguous, much more functional than ecological; they consider it a finite resource, an indispensable life patrimony, however there was no coherence between such conceptions and the self-reported behaviors of water use. Results indicated three important predictors of pro-environmental behavior: sex of respondent, New Ecological Paradigm Scale and telephone/address left for eventual contact to participate in future environmental campaigns. They may be used in additional studies for theoretical development, or to assist in the planning of programs of environmental education, aimed at the inhibition of the effects of a culture of consumption and of an utilitarian perception of water, extending individual and collective efforts towards the preservation of common resources as water

Determinação da condutividade do solo para agricultura: uma metodologia utilizando propagação de ondas AM

Agriculture is an essential activity to the human development, the tendency is that their need to increase according to the increase in world population. It is very important to take the maximum performance that is possible of each land without degrading it, a frequently monitoring is essential for the best performance. The purpose of this work is, nondestructively, to monitor the surface electrical conductivity of the soil in a demarcated area, as on a plantation, using low frequency radio waves. The conductivity is directly linked to the amount of water in the area and nutrients, therefore a periodic or even permanent monitoring increases significantly the efficient of the use of the soil. They will be used long-wave radio transmission or medium whose main characteristic to spread over the surface of the earth. It is possible to choose an AM radio with location, frequency and power of the transmission known or generate the signal. The studied method computes the conductivity of the ground in a straight line between two measured points, so it can be used in smaller or larger size fields. Measurements were carried out using an electromagnetic field strength analyzer. The data obtained in the measurements are processed by a numerical calculation program, in our case Matlab. It is concluded that the recommendations of the ITU (International Telecommunication Union) on the conductivity of soil in Brazil is far from reality, on some routes the recommendations indicate the use of the electrical conductivity of the soil 1 mS/m, while the measurements was found 19 mS/m. With the method described a precision farmer, once initial research for about a year, can monitor the humidity and salinity of the land, with the ability to predict the area and the most suitable time for irrigation and fertilization, making management more efficient and less expensive, while optimizing water use, natural resource increasingly precious.