Precision And Accuracy Of Pest And Pathogen Damage Assessment In Young Eucalypt Plantations

Fungal pathogens, browsing mammals, birds, insects, nutrient deficiencies, drought, frost and waterlogging are all damaging agents to plantation species. The subsequent loss in leaf tissue or reduced photosynthetic potential can reduce growth and potentially lead to tree death. The Crown Damage Index (CDI) was developed in Australia to quantify damage in young eucalypt plantations. The accuracy and precision of assessing damage at a tree level were determined to ensure the reliability, objectivity and repeatability of the CDI method. Nine assessors, with varying levels of experience, estimated damage on three plots of fifty trees each, to obtain an understanding of the subjectivity of assessing damage caused by insects (e.g. Chrysophtharta spp.) and fungal pathogens (e.g. Mycosphaerella spp.) on Eucalyptus globulus. Damage levels were measured by destructive sampling to enable direct comparisons between estimates and damage levels to be made. The most experienced assessors provided the most repeatable estimates and were generally the most accurate. The incidence of foliar necrosis was the least subjective measure while defoliation was the most subjective and the least accurate of the indices measured. All assessors, regardless of experience, were able to predict the Crown Damage Index (a combined index of all damage classes) to within 12% of measured damage levels.     

Relationship between Pb and Cd accumulations in house crow,their habitat,and food content from Klang area,Peninsular Malaysia

Heavy metal pollution has become a global concern due to accumulation in tissue and transferable effects to humans via the food chain. This study focused on monitoring the accumulation of cadmium (Cd) and lead (Pb) in surface soil and body content: bone, heart, brain, liver, lung, muscle, kidney, feathers, feces, and gizzard contents of house crow Corvus splendens in the Klang region, Malaysia. The results revealed the occurrence of Pb and Cd in all biological samples from house crows, food contents, and surface soil samples. Heart and kidney accrued high amounts of Cd, while high amounts of Pb were found to accumulate in bones and feathers. Major discrepancies were also discovered in the concentrations of metals between juvenile and adults, as well as female and male bird samples. Concentrations of Pb and Cd in house crow internal tissues correlated significantly with that of bird feathers, but none could be established with that of surface soil. In addition, a significant correlation was observed between Pb concentration in the internal tissues to that of the feces, but the same was not the case when compared with the surface soil concentration. Metal accrual in the house crows feathers and feces may be through a long-term transmission via the food chain, which are eliminated from feathers via molting. This may suggest the utility of molted breast feathers of house crow in the bio-monitoring of Cd and Pb contamination, whereas feces of house crow appear only to be suitable for the bio-monitoring of Pb contamination.     

Green examination: integration of technology for sustainability

The recent development of infrastructure all around the world has resulted in an increasing trend of online examination in universities. The paper is an approach in theory and practical aimed at analyzing the feasibility of sustainable examination in four universities and its environmental impact reducing the paper use terming it as green examination. The paper studied the integration of sustainability through the use of computers and technology in the examination of the universities viz. King Khalid University (KKU), Saudi Arabia, Integral University (IU), India, Aligarh Muslim University (AMU), India, and The Hague University (HU), The Netherlands. The study has analyzed the trend of paper requirement, paper utilized and paper wasted in all the four universities. The environmental impact resulting from reduced paper use has been also analyzed. The feasibility of e-examination, its implementation and the implications has been undertaken in the study. The study concludes that the e-examination can almost make the examinations paperless and feasible in the four universities.     

Negative carbon via Ocean Afforestation

Ocean Afforestation, more precisely Ocean Macroalgal Afforestation (OMA), has the potential to reduce atmospheric carbon dioxide concentrations through expanding natural populations of macroalgae, which absorb carbon dioxide, then are harvested to produce biomethane and biocarbon dioxide via anaerobic digestion. The plant nutrients remaining after digestion are recycled to expand the algal forest and increase fish populations. A mass balance has been calculated from known data and applied to produce a life cycle assessment and economic analysis. This analysis shows the potential of Ocean Afforestation to produce 12 billion tons per year of biomethane while storing 19 billion tons of CO₂ per year directly from biogas production, plus up to 34 billion tons per year from carbon capture of the biomethane combustion exhaust. These rates are based on macro-algae forests covering 9% of the world's ocean surface, which could produce sufficient biomethane to replace all of today's needs in fossil fuel energy, while removing 53 billion tons of CO₂ per year from the atmosphere, restoring pre-industrial levels. This amount of biomass could also increase sustainable fish production to potentially provide 200 kg/yr/person for 10 billion people. Additional benefits are reduction in ocean acidification and increased ocean primary productivity and biodiversity.     

Mineralization of particulate organic matter derived from coral-reef organisms in reef sediments of the Gulf of Aqaba

In situ and laboratory incubation experiments in a fringing reef in the Gulf of Aqaba were performed to study degradation rates of particulate organic matter in reef sediments. Coral mucus, clam eggs, and zooxanthellae were used as model particulate organic compounds for these experiments. Aerobic and anaerobic mineralization rates were calculated by dissolved inorganic carbon (DIC) and O₂ fluxes from the sediments under different particulate organic matter additions. Fast enhancement (approximately twofold) of O₂ and DIC fluxes were found with the addition of coral mucus and clam eggs compared with control incubations without addition. Most of the degradation is believed to have occurred anaerobically rather than aerobically (DIC:O₂ ratios were 4.3-28.1). Higher degradation rates of coral mucus and clam eggs were estimated in carbonate sediment than in silicate sediment (1.2-1.6-fold), which was attributed to the different physical and chemical properties of both sediments. Our study shows the significance of the reef sediment as a suitable site for microbial degradation of particulate organic material excreted from different reef community organisms. This may increase the regeneration of nutrients in the reef environment necessary to sustain high biological productivity.     

Organochlorines and PCBs in Tilapia zillii from Lake El-Manzala, Egypt

A freshwater fish species, Tilapia zillii, from Lake El-Manzala was analysed for concentrations of several organochlorine pesticides (OCs) and polychlorinated biphenyl (PCBs) in liver, gonads, mesenteric fat, flesh, and digestive tract in mature fish during the breeding season. PCBs and OCs were calculated in ng g^-1 dry weight (dw) in homogenized samples. The obtained results revealed differences in lipid content between these different organs. The females showed a higher lipid content than did males. There was a significant positive correlation between the lipid content and the concentrations of detected organochlorines and PCBs. The results are concomitant with the lipophilicity of studied compounds. However, the recorded concentrations of these studied pollutants still do not exceed the international hazardous levels.     

Expert System for Terrestrial Vegetation Distribution, Potential Impact and Mitigation Abatement Measures

The tropical rainforest of Malaysia holds one of the richest flora in the world. The favourable climate has produced flora of amazing richness and variety. Terrestrial vegetation of tropical rainforests is an important feature of the environment. Plants play a major role in the environment and conservation of a particular environment depends fundamentally on the maintenance of existing plants and their communities and hierarchies. Interference in the balance of the ecosystem may produce radical changes that lead to progressive deviations from the original situation. Therefore, the application of a computer technology in the form of an expert system (ES) will be able to help in the analysis and management of the EIA information. The ES is named VEGEVIC. Application of the system will lead to greater consistency in the application of EIA through implementation of a standard approach.     

Toxicity of Heavy Metals on Scenedesmus quadricauda (Turp.) de Brébisson in Batch Cultures (7 pp)

Background Aquatic environments are often exposed to various pollutants like heavy metals that are released from industrial, agricultural and domestic wastes. Emissions of heavy metals can then enter all ecosystems and bring about severe problems in plants, especially algae depending on the concentrations of a given element. The objective of the investigation presented is to detect toxic effects due to some heavy metals in the biomass of green alga Scenedesmus quadricauda. Methods All experiments were conducted with axenic cultures of the green alga Scenedesmus quadricauda (Turp.) de Brebisson (Chlorococcales, Chlorophyta). The cultures were grown in Chu-no.10 medium, and optimum physical and chemical growth conditions were provided to get higher growth rates and lower doubling times of cells. Growth of the micro algal cultures was measured on a daily schedule by counting cultures and determination of chlorophyll-a. The sterile-filtered heavy metal concentration solutions (Cd, Pb and Cu) were prepared and added as stock solutions of their salts (CdCl2*2.5 H2O, Pb(NO3)2*H2O and CuSO4*5 H2O). Results and Discussion The growth decreased gradually with the alga exposed to Cd at 0.05, 0.1, and 0.5 mg/L in comparison with the control whereas 1 mg/L Cd2+ had a clearly destructive effect. The growth was decreased with Pb at 15, 20 and 25 mg/L gradually, while at 30 mg/L the effect was more pronounced. When Cu was used, the growth was increased gradually at 0.5, 1 and 1.5 mg/L and vice versa at 2 mg/L. Conclusion There were differences in toxic effects of the metals with different metal as well as their concentrations and the time of exposure.