877 resultados para Nilambur teak plantations
Resumo:
This paper examines idiosyncrasies of tea plantation culture and politics in relation to Sri Lankan national and popular cultural typologies, with special reference to female tea plantation workers. Tea production in Sri Lanka is heavily based on manual labour, and it is the largest industry that provides accommodation for employees and their families. In this paper, it is argued that politico-cultural production relations have dominated labour productivity in tea plantations. Ways in which female workers have been marginalized, through patriarchal politics, ethnicity, religion, education, elitism, and employment are explained. This culture of the plantation community operates negatively with respect to the management agenda. It is also argued that social capital development in tea plantations is important not only for productivity improvement, but also for reasons of political and social obligation for the nation, because migrant plantation workers have been working and living in plantations over 150 years.
Resumo:
This paper reviews nitrogen (N) cycle of effluent-irrigated energy crop plantations, starting from wastewater treatment to thermo-chemical conversion processes. In wastewater, N compounds contribute to eutrophication and toxicity in water cycle. Removal of N via vegetative filters and specifically in short-rotation energy plantations, is a relatively new approach to managing nitrogenous effluents. Though combustion of energy crops is in principle carbon neutral, in practice, N content may contribute to NOx emissions with significant global warming potential. Intermediate pyrolysis produces advanced fuels while reducing such emissions. By operating at intermediate temperature (500°C), it retains most N in char as pyrrolic-N, pyridinic-N, quaternary-N and amines. In addition, biochar provides long-term sequestration of carbon in soils.
Resumo:
This study estimates above-ground biomass in high density plantations of six important semi-arid tree species at Palwal (70 km from Delhi) irrigated with secondary treated sewage water at the rate of 0, 25, 50 and 100% of daily net evaporation potential (EP). In 2.5 y old plantations (plant spacing, 2 m x 2 m for single stem species and 2 m x 1 m for multi-stem species), Melia azedarach showed fairly high biomass production (38.4 t/ha) followed by Ailanthus excelsa (27.2 t/ha). Order of biomass production (kg / tree) was: Eucalyptus tereticornis (24.1) > A. excelsa (21.8) > M. azedarach (12.6) > Populus deltoides clone G 48 (8.3) > Alstonia scholaris (6.6)> Pongamia pinnata (3.7). Survival of plants after 2.5 y ranged from 25.2% in P. deltoides to 71.7% in P. pinnata, and had a significant effect on biomass production per unit area. ANOVA shows that levels of irrigation (0 - 100%) did not have statistically significant effect on plant growth. Correlation between diameter and biomass was found highly significant (p< 0.01) with R2 nearing to 1.
Resumo:
This study analyses feasibility of using domestic wastewater for fertigation of tree crops. Wastewater samples from different sources in domestic sector were analyzed and evaluated in terms of water quality and quantity. Water is rich in plant nutrients. However, due to possible presence of toxic ions and microbial load, it is recommended that direct use of wastewater for fertigation be limited to timber plantation and energy generation from biomass.
Resumo:
Covers part of Harrison County (W.Va.)
Resumo:
In Colombia coffee production is facing risks due to an increase in the variability and amount of rainfall, which may alter hydrological cycles and negatively influence yield quality and quantity. Shade trees in coffee plantations, however, are known to produce ecological benefits, such as intercepting rainfall and lowering its velocity, resulting in a reduced net-rainfall and higher water infiltration. In this case study, we measured throughfall and soil hydrological properties in four land use systems in Cauca, Colombia, that differed in stand structural parameters: shaded coffee, unshaded coffee, secondary forest and pasture. We found that throughfall was rather influenced by stand structural characteristics than by rainfall intensity. Lower throughfall was recorded in the shaded coffee compared to the other systems when rain gauges were placed at a distance of 1.0 m to the shade tree. The variability of throughfall was high in the shaded coffee, which was due to different canopy characteristics and irregular arrangements of shade tree species. Shaded coffee and secondary forest resembled each other in soil structural parameters, with an increase in saturated hydraulic conductivity and microporosity, whereas bulk density and macroporosity decreased, compared to the unshaded coffee and pasture. In this context tree-covered systems indicate a stronger resilience towards changing rainfall patterns, especially in mountainous areas where coffee is cultivated.
Resumo:
Changes in soil sulfur (S) fractions were assessed in oil palm and food garden land use systems developed on forest vegetation in humid tropical areas of Popondetta in northern Province. The study tested a hypothesis that S in food gardens are limiting nutrient factor and are significantly lower than in plantations and forests. Subsistence food gardens are under long-term slash and burn practice of cropping and such practice is expected to accelerate loss of biomass S from the ecosystem. From each land use, surface soil (0–15 cm) samples were characterised and further pseudocomplete fractionated for S. Conversion of forest to oil palm production decreased (p<0.001) soil pH and electrical conductivity values. The reserve S fraction in soil increased significantly (p<0.05) due to oil palm production ( 28 %) and food gardening activity (∼ 54 %). However, plant available SO42--S was below 15 mg kg^(−1) in the food garden soils and foliar samples of sweet potato crop indicating deficiency of plant available S. Soil organic carbon content (OC) was positively and significantly correlated to total S content (r=0.533; p<0.001) among the land use systems. Thus, crop management practices that affect OC status of the soils would potentially affect the S availability in soils. The possible changes in the chemical nature of mineralisable organic S compounds leading to enhanced mineralisation and leaching losses could be the reasons for the deficiency of S in the food garden soils. The results of this study conclude that long-term subsistence food gardening activity enriched top soils with reserve S or total S content at the expense of soluble S fraction. The subsistence cropping practices such as biomass burning in food gardens and reduced fallow periods are apparently threatening food security of oil palm households. Improved soil OC management strategies such as avoiding burning of fallow vegetation, improved fallows, mulching with fallow biomass, use of manures and S containing fertilisers must be promoted to sustain food security in smallholder oil palm system.
Resumo:
A interceptação da chuva pela copa das florestas tem grande relevância no ciclo biogeoquímico de nutrientes nos solos de baixa fertilidade sob florestas nativas e plantadas. Entretanto, pouco se sabe sobre as modificações na qualidade dessa água e no balanço hidrológico após a interceptação pela copa do eucalipto sob condições de plantios puros e mistos com leguminosas, no Brasil. Amostras de água de chuva (RF), de precipitação interna (TF) e de escoamento pelo tronco (SF), foram coletadas e analisadas quimicamente em plantios puros de mangium (espécie fixadora de nitrogênio atmosférico - EFN), guachapele (EFN) e eucalipto (espécie não fixadora de nitrogênio - ENFN) e consorciados com guachapele e eucalipto, em Seropédica, Rio de Janeiro. Nove coletores de escoamento pelo tronco (colocados em árvores), nove pluviômetros posicionados ao acaso nos plantios e três fora da influência deles foram utilizados no monitoramento durante 5,5 meses. A mangium direcionou 33,4% do total precipitado para o seu tronco. Uma estimativa baseada na correção da média anual precipitada na área (1.213 mm) indicou uma contribuição no aporte de nutrientes (kg ha-1) de 8,42; 0,95; 19,04; 6,74; 4,72; e 8,71 kg ha-1 dos elementos N-NH4+, P, K+, Ca+2, Mg+2 and Na+, respectivamente. A precipitação interna participou com a maior parte da contribuição, em comparação com o escoamento pelo tronco. Os maiores aportes de N-NH4+ (15,03 kg ha-1) e K+ (179,43 kg ha-1) foram observados sob as copas de guachapele em plantio puro. Elevada quantidade de Na+ denota influencia do mar próximo à área experimental. A mangium foi a espécie adaptada à competição por água. Comparativamente ao plantio puro de eucalipto, o plantio misto intensificou a lixiviação de N, Ca e Mg da copa, enquanto o de K e o P aportaram em menores quantidades nesse plantio.