Surveying macro-invertebrate diversity in the Tons river,Doon Valley,India

A survey of macro-invertebrates and their monthly variations occupying the Tons river in Doon Valley was conducted from August 2003–July 2004. Macro-invertebrate collections and water samples were taken from three sampling stations every month during the period of study. All the hydrological attributes were measured monthly for 1 year. The present study showed that the water velocity, hydromedian depth, turbidity and dissolved oxygen and nature and size of the bottom substrates do play a major role in determining the macro-invertebrate diversity of Tons river. The ecological relevance of the measured hydrological attributes was investigated by comparing their degree of correlation with invertebrate density and diversity. The Shannon–Wiener index (H′) of macro-invertebrates was found to be highest (3.60) during spring season (February and March) and lowest (2.59) during monsoon season (July and August). The high values of diversity index of macro-invertebrates at all the three sampling sites indicate diverse macro-invertebrate communities in the Tons river in Doon Valley, India.     

Evidence for contact sex recognition pheromone of the Asian longhorned beetle,<Emphasis Type="Italic"> Anoplophora glabripennis</Emphasis> (Coleoptera: Cerambycidae)

Field observations of the Asian longhorned beetle (Anoplophora glabripennis) mating behavior in China suggested that a female-produced contact pheromone was almost certainly involved in sex recognition. Gas chromatography–mass spectrometry (GC-MS) analysis of A. glabripennis adults' whole body cuticular extracts indicates that a series of long-chain hydrocarbons comprise the cuticular waxes of both sexes. Although for the most part the GC profiles are similar for the two sexes, five monounsaturated compounds were consistently more abundant in samples from females than in those from males. These compounds were identified as (Z)-9-tricosene, (Z)-9-pentacosene, (Z)-7-pentacosene, (Z)-9-heptacosene, and (Z)-7-heptacosene in the approximate ratio of 1:2:2:8:1, respectively. Antennal and palpi contact to a polypropylene micro-centrifuge tube coated with a synthetic mixture of the five compounds stimulated copulatory behavior in males.Electronic Supplementary Material  Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material.     

Assessment of bio-medical waste management in three apex government hospitals of Agra

Waste management practices in three apex government hospitals of Agra viz., Sarojini Naidu Medical College, Lady Lyall Maternity Hospital and District Hospital were studied during January 2004-January 2005. Data were collected with the help of (i) personal observations of the waste treatment and disposal practices and (ii) assessment of knowledge, attitude and practices of working personnel with the help of questionnaires. The results obtained indicated lack of knowledge and awareness regarding legislations on bio-medical waste management even among qualified hospital personnel. None of these hospitals were equipped with higher technological options e.g. incinerator autoclave, microwave and had no facilities to treat the liquid waste generated inside the hospital. It is concluded that generation and implementation of a waste management policy institutiona/organizational set up, training and motivation must be given paramount importance to meet the current needs and standards of bio-medical waste management in these hospitals.     

Novel chitosan/PVA/zerovalent iron biopolymeric nanofibers with enhanced arsenic removal applications

Enhanced removal application of both forms of inorganic arsenic from arsenic-contaminated aquifers at near-neutral pH was studied using a novel electrospun chitosan/PVA/zerovalent iron (CPZ) nanofibrous mat. CPZ was carefully examined using scanning electron microscopy (SEM) equipped with energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), atomic fluorescence spectroscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA). Application of the adsorbent towards the removal of total inorganic arsenic in batch mode has also been studied. A suitable mechanism for the adsorption has also been discussed. CPZ nanofibers mat was found capable to remove 200.0?±?10.0 mg g^?1 of As(V) and 142.9?±?7.2 mg g^?1 of As(III) from aqueous solution of pH 7.0 at ambient condition. Addition of ethylenediaminetetraacetic acid (EDTA) enabled the stability of iron in zerovalent state (ZVI). Enhanced capacity of the fibrous mat could be attributed to the high surface area of the fibers, presence of ZVI, and presence of functional groups such as amino, carboxyl, and hydroxyl groups of the chitosan and EDTA. Both Langmuir and Freundlich adsorption isotherms were applicable to describe the removal process. The possible mechanism of adsorption has been explained in terms of electrostatic attraction between the protonated amino groups of chitosan/arsenate ions and oxidation of arsenite to arsenate by Fentons generated from ZVI and subsequent complexation of the arsenate with the oxidized iron. These CPZ nanofibrous mats has been prepared with environmentally benign naturally occurring biodegradable biopolymer chitosan, which offers unique advantage in the removal of arsenic from contaminated groundwater.     

Biology and management of two important <Emphasis Type="Italic">Conyza</Emphasis> weeds: a global review

Weed management is one of the prime concerns for sustainable crop production. Conyza bonariensis and Conyza canadensis are two of the most problematic, noxious, invasive and widespread weeds in modern-day agriculture. The biology, ecology and interference of C. bonariensis and C. canadensis have been reviewed here to highlight pragmatic management options. Both these species share a unique set of biological features, which enables them to invade and adapt a wide range of environmental conditions. Distinct reproductive biology and an efficient seed dispersal mechanism help these species to spread rapidly. Ability to interfere strongly and to host crop pests makes these two species worst weeds of cropping systems. These weed species cause 28–68 % yield loss in important field crops such as soybean and cotton every year. These weeds are more prevalent in no-till systems and, thus, becoming a major issue in conservation agriculture. Cultural practices such as crop rotations, seed rate manipulation, mulching, inter-row tillage and narrow row spacing may provide an effective control of these species. However, such methods are not feasible and applicable under all types of conditions. Different herbicides also provide a varying degree of control depending on crop, agronomic practices, herbicide dose, application time and season. However, both these species have evolved resistance against multiple herbicides, including glyphosate and paraquat. The use of alternative herbicides and integrated management strategies may provide better control of herbicide-resistant C. bonariensis and C. canadensis. Management plans based on the eco-biological interactions of these species may prove sustainable in the future.     

Copper chitosan nanocomposite: synthesis, characterization, and application in removal of organophosphorous pesticide from agricultural runoff

Purpose

Removal of malathion from agricultural runoff was studied using novel copper-coated chitosan nanocomposite (CuCH)??a biopolymeric waste obtained from marine industry.

Methods

Synthesis and characterization of the adsorbent using different spectral techniques like Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer, Emmett, and Teller surface analyzer have been carried out. Equilibrium studies have been carried out to optimize the dose rate, pH, and the reaction time. Parathion and methyl parathion removal were also evaluated by CuCH in the batch mode. Using gas chromatography?Cmass spectrometry (GC?CMS) and FTIR studies suitable mechanism for adsorption has been suggested.

Results

The particle size of the adsorbent ranged from 700 to 750?nm. The surface area was found to be 20?m²?g^-1 with a pore volume of 0.11?cc?g^-1. The maximum adsorption capacity of malathion by CuCH was found to be 322.6?±?3.5?mg?g^-1 at an optimum pH of 2.0. Presence of copper ions enhanced the adsorption capacity of the adsorbent. The reaction was found to follow pseudo second-order kinetics with a rate constant of 0.53?g?mg^-1?min^-1. Evidence from FTIR indicated that copper ions form a dithionate complex with malathion during the adsorption stage. The adsorbent was found to remove malathion completely from spiked concentration of 2?mg?l^-1 in the agricultural run-off samples. It was also found that CuCH removed other organophospurous pesticides like methyl parathion and parathion under prevailing conditions.

Conclusions

The results indicated that CuCH could be applied for the removal of organophosphorous pesticides.     

Biosynthesis of (S)-1-(1-naphthyl) ethanol by microbial ketoreductase

Environmental Science and Pollution Research - (S)-1-(1-naphthyl) ethanol (SNE) is a chiral drug intermediate for the production of mevinic acid analog, a potent cholesterol agent. It acts as an...     

Sex pheromone of the tea aphid,Toxoptera aurantii (Boyer de Fonscolombe) (Hemiptera: Aphididae)

The tea aphid, Toxoptera aurantii, also called the “black citrus aphid”, is one of the most destructive insect pests in commercial tea plantations and gardens in southern China. In autumn, declining day length triggers production of winged T. aurantii sexuparae, which produce both winged males and wingless oviparae. Oviparous females then release sex pheromone that attracts potential mates. GC–MS analysis of volatile headspace extracts of T. aurantii oviparae revealed that they emit (4aS,7S,7aR)-nepetalactone (I) and (1R,4aS,7S,7aR)-nepetalactol (II) in a ratio of 4.3–4.9:1. Field-trapping experiments with synthetic I and II singly or as two-component blends of different doses and ratios showed significant attraction of T. aurantii males, as well as weak attraction of sexuparae. Identification of the T. aurantii sex pheromone provides a new opportunity for developing a pheromone-based monitoring and management strategy for the sexual phase of tea aphids and, possibly, the alate sexparous generation in late summer and fall.     

Persistence of chlorpyriphos in okra (Abelmoschus Esculentus) fruits and soil

Persistence of cypermethrin and chlorpyriphos in okra and soil were studied following the application of pre-mix formulation of insecticides Action 505EC (chlorpyriphos 50%?+?cypermethrin 5%) at single (275?g a.i.?ha^?1) and double dose (550?g a.i.?ha^?1). The average initial deposits of chlorpyriphos in okra were observed to be 0.07 and 0.15?mg?kg^?1 in single and double dose, respectively, which dissipated to 92% after 10 days for both the dosages. Residues of soil under okra crop were found to be 0.15?mg?kg^?1 at the single and 0.36?mg?kg^?1 at the double doses. These residues persisted up to 3 days at single and 5 days at double dose. The half-life (t _1/2) periods of chlorpyriphos on okra and soil were observed to be 0.6 days and 1.9 days for single and double dose, respectively. Residues of chlorpyriphos reached below detectable level (BDL) of 0.01?mg?kg^?1 in okra fruits after 7 days at single dose and in 15 days in double dose. In soil, residues of chlopyriphos persisted up to 5 and 7 days in single and double dose, respectively. Following foliar applications of a insecticide formulation (Action 505EC, (chlorpyriphos 50%?+?cypermethrin 5%) on okra at @ 275 and 550?g active ingredient (a.i.)?ha^?1 resulting in active applications of chlorpyriphos at the rate of 250 and 500?g a.i.?ha^?1 the average initial deposits of chlorpyriphos in okra were observed to be 0.07 and 0.15?mg?kg^?1, respectively. These residue levels dissipated to 92% after 10 days at both the dosages. Residues of soil under the okra crop were found to be 15?mg?kg^?1 at the single and 36?mg?kg^?1 at the double dose. The residues persisted up to 3 days at the single and 5 days at the double dose. The half-life (t _1/2) periods of chlorpyriphos on okra were observed to be 0.6 days for application rates, and 1.9 days for soil. Okra fruits and soil samples collected on the 7th and 15th day after application did not show any chlorpyriphos residues above their determination limits of 0.01 and 0.005?mg?kg^?1, respectively.     

Short-term Emissions of Ammonia and Carbon Dioxide from Cattle Urine Contaminated Tropical Grassland Microcosm

The study was designed to understand the emissions of ammonia (NH₃) and carbon dioxide (CO₂) from a single cattle urination event on a tropical grassland and underline the significance of the emissions in the context of huge animal population grazing on large pasture areas in some countries. Emissions of ammonia (NH₃) and carbon dioxide (CO₂) were monitored for three weeks from a tropical grassland (dominated by Cynodon dactylon Pers.) microcosm contaminated with cow and buffalo urine. The grassland microcosms were treated with urine (50 and 100 ml of each) only once and irrigated with water once every week. Ammonia was sampled by an automatic sampling system comprising of a vacuum pump, three-way stopcocks and rubber tubing and an impinger containing suitable absorbing solution (H₂SO₄), connected to the tubing suitably. The sampled gas, after sucked by the vacuum pump and absorbed in H₂SO₄, was allowed to enter the closed microcosm again maintaining internal pressure of the microcosm. Carbon dioxide was sampled by absorption in an alkali (NaOH) trap inside the microcosm. Both NH₃ and CO₂ emissions were highly variable temporally and there was no continuous increasing or decreasing emission trend with time. Respectively, 45 and 46% of total NH₃-N were emitted within first 48 h from 50 and 100 ml cow urine application while the corresponding values for buffalo urine were 34 and 32%. Total NH₃-N emissions, integrated for sampling days (i.e. 1, 2, 3, 4, 6, 15, 18 and 21st) were 11 and 6% in cow and 8 and 5% in buffalo urine, of the total-N added through 50 and 100 ml urine samples. Carbon dioxide emissions were standardized at 25 ^∘C by using a suitable formula which were lower than actual emissions at actual soil temperature (> 25 ^∘C). Carbon dioxide emission rates were classified on the basis of soil repiratory classification and classes ranged from moderately low soil activity up to unusually high soil activity, the latter observed only on very few sampling days. Grasses in the microcosm had shown appreciable growth after urine application. Although variable and somewhat unpredictable, emissions were appreciable and that too only from a patch of single urination, indicating to the huge magnitude of total emissions under the scenario of thousands of cattle grazing on hundreds of acres of grasslands in a tropical country.