Monitoring of biophysical parameters of cashew plants in Cambodia using ALOS/PALSAR data

An accurate estimation of a plant's age is required for the prediction of yield and management practices. This study demonstrates the relationship between backscattering properties (σ°) of Phased Array type L-band Synthetic Aperture Radar (PALSAR) dual polarimetric data with cashew plants' biophysical parameters (height, age, crown diameter, diameter at breast height, basal area, tree density, and biomass) in Cambodia. PALSAR σ° has shown a positive correlation with the biophysical parameters of cashew plants. The value of σ° increases with the age of cashew plants. At a young stage, the cashew plants show a higher rate of an increase in σ° compared to that at the mature stage. The σ° horizontal polarization transmitted and vertical received (HV) shows higher sensitivity to the plant's growth than σ° horizontal polarization transmitted and received (HH). High backscattering and low variations were observed at mature stage (8–12 years) of cashew plantation. Saturation in backscattering has shown from the age of about 13 years. The validation results indicate strong coefficient of determination (R ²?=?0.86 and 0.88) for PALSAR-predicted age and biomass of cashew plants with root mean square error?=?1.8 years and 16.3 t/ha for age and biomass, respectively. The correlations of σ° (HH) with biophysical parameters observed in the dry season were better than those of the rainy season because soil moisture interferes with backscattering in the rainy season. Biomass accumulation rate of cashew plants has been predicted that would be useful for selection of plants species to enhance carbon sequestration. This study provides an insight to use PALSAR for the monitoring of growth stages of plants at the regional level.     

Sanitation of seawater effluent from seaweed processing plants using a photo-catalytic TiO2 oxidation

A fine porcelain open-cell photo-catalytic filter with titanium dioxide (TiO(2)) was evaluated for sterilization and sanitation of bio-polluted industrial water. In simulated seawater industrial effluent samples, the populations of Escherichia coli and Vibrio parahaemolyticus quickly decreased and reached non-detectable level within 10min. In seawater effluents from a seaweed processing plant, the bacterial populations in two samples quickly decreased by more than 10(3). In another two samples the decreases were slow and lowered by less than 10(2). Using fluorescence microscopy, it was indicated that the bacterial cells treated with photo-catalytic TiO(2) were damaged. In addition, the protein concentration in simulated seawater effluent slowly decreased using the photo-catalytic TiO(2) reaction; and reached similar concentrations as seawater near cultured seaweed beds. These results indicate that using a reactor with a TiO(2) photo-catalyst filter was effective for the sanitation of seawater effluents.     

Dechlorination/hydrogenation and destruction reactions of PCDDs in OCDD-added fly ash heated under vacuum

Octachlorodibenzo-p-dioxin (OCDD)-added, pretreated fly ash was heated under vacuum at sample temperatures ranging from T(s)=450 to 650 K. The fly ash and liquid nitrogen-cooled trap samples were analyzed for DD/DF through OCDD/DF. The total amounts of DD through OCDD decrease with increasing T(s), which indicates that dechlorination/hydrogenation (DCH) reactions are not the only reaction channels. Reduction of toxic equivalent (TEQ) for PCDDs by more than 99% was achieved in the fly ash by the vacuum heat treatment at T(s)=650 K for 4 h. The total amount of PCDDs and DD detected in the liquid nitrogen-cooled trap relative to that of added OCDD was about 17%, i.e., PCDDs and DD which were adsorbed to the fly ash surfaces can evaporate into the gaseous phase. The difference between the evaporation behavior of PCDDs in the present and the previous studies is discussed in the light of their states of existence.     

Estimation on Biodegradability of Poly (3-hydroxybutyrate-<Emphasis Type="Italic">co</Emphasis>-3-hydroxyvalerate) (PHB/V) and Numbers of Aerobic PHB/V Degrading Microorganisms in Different Natural Environments

To assess the capacity of the natural environment for degrading PHB/V, the film-MPN method proposed previously was modified to estimate the numbers of PHB/V degrading microorganisms (degraders) in various environments. The First-Order Reaction (FOR) model was used to determine the appropriate incubation period for the method. Numbers of aerobic PHB/V degraders were estimated in garden soil, paddy field soil, farm soil, river bank soil, infertile garden soil, river water, activated sludge, and seawater by the film-MPN method. Results were compared with those estimated by the clear-zone technique and showed that the film-MPN method was suitable for estimating the numbers of PHB/V degraders in the environments tested. On the other hand, biodegradability of injection molded PHB/V samples was investigated in several kinds of environments. The changes of weight were studied and results showed that biodegradability of PHB/V related to the numbers of PHB/V degraders in similar ecosystem in different regions. In different environments the biodegradability of PHB/V not only related to the number of PHB/V degraders, but also depended on whether there were conditions for the PHB/V degraders to grow and proliferate easily in the environment.     

Genetic stock structure of the swordfish (Xiphias gladius ) inferred by PCR-RFLP analysis of the mitochondrial DNA control region

Restriction fragment length polymorphism (RFLP) analysis was performed on PCR amplified DNA fragments containing the control region of the swordfish (Xiphias gladius Linnaeus, 1758) mitochondrial DNA. A total of 456 individuals comprising 13 local samples (six Pacific, three Atlantic, the Mediterranean Sea, two Indian Ocean and the Cape of Good Hope) were surveyed with four endonucleases (Alu I, Dde I, Hha I and Rsa I), yielding a total of 52 composite genotypes. Within-sample genotypic diversity (H) was high ranging from 0.702 to 0.962 with a value of 0.922 for the pooled sample. Significant geographic variation in the frequencies of genotypes and restriction patterns was revealed. The Mediterranean sample was highly distinct from all other samples. Further, Rsa I digestion revealed high levels of polymorphism in all but the Mediterranean samples, indicating that exogenous swordfishes rarely enter that body of water. Heterogeneity between the North and South Atlantic samples was significant, both of which differed from those of the Pacific. In contrast, the Indian Ocean samples were not significantly different from the samples of South Atlantic and Pacific. Genetic differentiation among the Pacific samples was low. The results indicate that the world-wide swordfish population is genetically structured not only among, but also within ocean basins and suggest that gene flow is restricted despite the absence of geographic barriers. Received: 28 August 1996 / Accepted: 2 October 1996     

Growth and reproduction ofCaprella danilevskii (Crustacea: Amphipoda) reared in the laboratory

Caprella danilevskii Czerniavski, an epifaunal amphipod crustacean, was successfully reared for two generations under laboratory conditions. Amphipods were maintained in pairs or fours in a Petri dish. Temperature and photoperiod were maintained at 20°C, and 14 h light: 10 h dark, respectively. Colonies of the diatomCylindrotheca closterium (Ehrenberg) Reumann and Lewin were provided as food source. The red algaGelidium amansii (Lamouroux) Lamouroux was used to provide an attachment substrate for the caprellids. Juveniles that emerged from the brood pouch were described as instar I. Subsequent instars were identified by molts. Juveniles molted successively at 2.5 to 6.5 d intervals. The body length of males at each instar increased exponentially, while that of females followed a sigmoid curve. A different pattern of flagellar segment addition in the antenna I of males and females was revealed. At the age of 20.8 d, females reached instar VII, and produced their first embryos. After 5.1 d, juveniles emerged from the brood pouch. On average, females produced 5.4 clutches successively at 5.0 d intervals. The number of offspring per spawning increased from 6.3 at instar VII to 22.0 at instar XII. The total number of offspring was 69.0 for a female throughout her life span.     

Persistent organic pollutants in Detroit River suspended sediments: polychlorinated dibenzo-p-dioxins and dibenzofurans,dioxin-like polychlorinated biphenyls and polychlorinated naphthalenes

Suspended sediments from the Detroit River were collected in 1999 and 2000 using sediment traps at sites ranging from western Lake Erie to southern Lake St. Clair and analyzed to determine the spatial distributions of contaminants including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs), dioxin-like PCBs (DLPCBs) and polychlorinated naphthalenes (PCNs). Concentrations of all three contaminant classes were clearly elevated at sites in the lower reaches of the river in the Trenton Channel. The potential influence of the Trenton Channel as a source of contamination to western Lake Erie was further evidenced by PCDD/PCDF homologue profiles, which indicated a contribution from chemical manufacturing in addition to the normal background combustion profile. Toxic equivalents (TEQs) for PCDDs/PCDFs generally exceeded those for DLPCBs; combined total TEQs in July 2000 for these two compound classes ranged from 2.30 pg/g in southern Lake St. Clair to 306 pg/g at a station just downstream of the outflow of Monguagon Creek in the Trenton Channel. The spatial distribution of PCN contamination was similar to that of PCDDs/PCDFs and DLPCBs, with the highest level of total PCNs (8200 ng/g) detected at a site in the Trenton Channel near Elizabeth Park; TEQs for PCNs in the Trenton Channel ranged from 73 to 3300 pg/g. The data indicate that PCNs represent a significant contribution to dioxin-like biological activity in Detroit River suspended sediments.     

CuCl2-catalyzed PCDD/F formation and congener patterns from phenols

Homologue and isomer patterns of polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) in CuCl2-catalyzed formation were studied in an isothermal flow reactor using a distribution of 20 phenols as measured in municipal waste incinerator (MWI) exhaust gases. A mixture of 20 phenols was synthesized and used as reactants for this study because phenols are known to be key precursors in the formation of PCDD/F. Experiments were conducted at 400 degrees C. The 92% of nitrogen (N2) and 8% of oxygen (O2) were used as a carrier gas. PCDD/F homologue and isomer patterns with dibenzo-p-dioxin (DD) and dibenzofuran (DF) were obtained from a mixture of 20 phenols. DF+PCDF formation was favored over DD+PCDD formation. The major homologue groups formed were non-chlorinated DD and DF, and PCDD/F homologue fraction decreased with the degree of chlorination. PCDD/F homologue and isomer distributions were almost constant. Phenol and lower chlorinated phenols present in high amount played an important role in PCDD/F congener distributions. The results presented here can be used as characteristics or fingerprints for homologue and isomer patterns of PCDD/F formation attribution in CuCl2-catalyzed reaction from phenols.     

Determination method of singlet oxygen in the atmosphere by use of α -terpinene

A chemical determination method of singlet oxygen in the atmosphere was established. The method employs a specific reaction of α -terpinene with singlet oxygen to produce the single product, ascaridole. Amberlite XAD-2 coated with α -terpinene was packed into a glass tube shielded from light and sample air was passed through the tube. Ascaridole formed was extracted with hexane from Amberlite XAD-2 and was determined by gas chromatography. The amount of singlet oxygen was calculated from that of ascaridole. Ascaridole was not formed by oxidation of α -terpinene with ozone, hydrogen peroxide and hydroxyl radical, and ascaridole formed by singlet oxygen was stable against these oxidants. The method was applied to actual polluted air and diurnal variations in the singlet oxygen were observed.