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Arsenic (As) mobilization to the groundwater of Brahmaputra floodplains was investigated in Titabor, Jorhat District, located in the North Eastern part of India. The groundwater and the aquifer geochemistry were characterized in the study area. The range of As concentration in the groundwater varies from 10 to 440 μg/l with mean concentration 210 μg/l. The groundwaters are characterized by high dissolved Fe, Mn, and HCO and low concentrations of NO and SO indicating the reduced conditions prevailing in the groundwater. In order to understand the actual mobilization processes in the area, six core drilling surrounding the two target tube wells (T1 and T2) with high As concentration (three drill-cores surrounds each tube well closely) was done. The sediment was analyzed its chemical, mineralogical, and elemental compositions. A selective sequential extraction suggested that most of the As in the sediment is bound to Fe oxides fractions (32 to 50 %) and the competition for adsorption site by anions (PO) also accounts to significant fractions of the total arsenic extracted. High variability in the extraction as well as properties of the sediment was observed due to the heterogeneity of the sediment samples with different chemical properties. The SEM and EDX results indicate the presence of Fe, Mn coating along with As for most of the sample, and the presence of As associated minerals were calculated using PHREEQC. The mobilization of As into the groundwater was anticipated to be largely controlled by the reductive dissolution of Fe oxides and partly by the competitive anions viz. PO. [ABSTRACT FROM AUTHOR]

Analysis of diversity, distribution and endemism of the family Rubiaceae for southern Assam has been made. The analyses are based on field observations in the three districts, viz., Cachar, Hailakandi and Karimganj, as well as data from existing collections and literature. The present study records 90 taxa recorded from southern Assam, four of which are endemic. Chassalia curviflora (Wall.) Thwaites var. ellipsoides Hook. f. and Mussaenda keenanii Hook.f. are rediscovered after a gap of 140 years. Mussaenda corymbosa Roxb. is reported for the first time from northeastern India, while Chassalia staintonii (H.Hara) Deb & Mondal is reported as a new record for Assam. [ABSTRACT FROM AUTHOR]

Two new palm leaf impressions, cf. Iguanura wallichiana and Palmacites makumensis sp. nov. are described from the Makum Coalfield, Tinsukia District, Assam. They belong to the Tikak Parbat Formation being considered as Late Oligocene (Chattian 28-23 Myr) in age. Their presence, along with the other known fossil records indicates that CMMT (cold month mean temperature) was not less than 18°C with plenty of rainfall, in the region during the period of deposition. [ABSTRACT FROM AUTHOR]

Two new and one known species of dorylaim nematodes are described and illustrated from Kaziranga National Park, Assam, India. Prothornenema vulvatum sp. nov. is characterized by having body 1.06–1.17 mm long; lip region cap-like, slightly rounded, offset by constriction with moderate labial and post-labial sclerotization; 10–11 μm long odontostyle; vulva a transverse slit; cuticle both anterior and posterior to vulva with two or three deep invaginations; female tail long filiform, male tail short conoid with 13 or 14 contiguous ventromedian supplements. Allodorylaimus kazirangus sp. nov. is characterized by having body 1.84–2.16 mm long; truncate, slightly offset lip region; 30 μm long odontostyle; amphids duplex; cardia short conoid, an asymmetrical ring-like structure surrounds the junction between pharyngeal base and cardia; transverse vulva; uterus characteristically long, tripartite with wide proximal portion followed by a long narrow intermediate portion with moderately sclerotized inner lining joining a wider pars dilatata distalis; short conoid tail with no sexual dimorphism and males with 13 or 14 contiguous ventromedian supplements. Thornia propinqua (Paesler, 1941) Andrássy, 1957 is redescribed. [ABSTRACT FROM AUTHOR]

Human–elephant conflict in India, driven by habitat loss and an expanding human population, is a complex challenge for biodiversity conservation. Determining if, how and why this conflict has changed over time will be an important step towards managing landscapes where people and elephants Elephas maximus coexist. This study combines social surveys and remote sensing data to analyse patterns in human–elephant conflict and land-use change over time. The reported experience of conflict increased dramatically in the early 1980s, with 85% of those surveyed indicating that conflict began after 1980. The expansion of conflict showed a significant southward trend and was associated with forest cover dropping below 30–40%. Based on our results we propose that a critical habitat threshold for human–elephant conflict may exist at 30–40% forest cover. Below this level, conflict expanded across the landscape. The existence of such a deforestation threshold may have important implications for landscape management in elephant range states that seek to avoid or mitigate further conflict. Maintenance of remaining forest areas, reforestation, and the creation of habitat corridors are strategies that could help prevent further expansion of conflict. [ABSTRACT FROM PUBLISHER]

One 2.5 m lacustrine sedimentary profile dated back to 6340 years BP from Deosila swamp under Rangjuli Reserve forest of Assam, Northeast India has been pollen analyzed for tracing past vegetation vis à vis climate variability since mid-Holocene. The pollen diagram has deciphered that during 6340 to 2970 years BP, tropical tree savannah type of vegetation grew in the region chiefly constituted of grasses interspersed with scattered trees of Salmalia, Dillenia, Emblica, Meliaceae along with sporadic presence of Artocarpus chaplasha, Symplocos, Ilex, Schima and Shorea robusta under relatively less cool and dry climatic condition with a little ameliorating trend at the upper column. The vegetation scenario implies poor growth of arboreals due to harsh abiotic dynamics causing changes in drainage system. Subsequently during 2970 to 1510 years BP, tropical mixed deciduous forest succeeded tree savannah with invasion of Shorea robusta, Lagerstroemia, Lannea, Semecarpus and Acacia under warm and humid climate. The gradual enrichment of organic soil might have been conducive for better growth of both deciduous and semi evergreen arboreals as found today. However, during 1510 to 540 years BP, the forest groves became more strengthened resulting establishment of tropical deciduous Sal forest. Steady increment of Shorea robusta along with Lannea, Lagerstroemia, Terminalia, Sapotaceae, Albizia and Adina was observed probably due to influence of active SW monsoon under increased warm and humid climatic regime. This is well substantiated by the consistent occurrence of marshy and aquatic taxa along with ferns and fungal remains. Finally during 540 years BP onward the reduced forest floristics have obviously been envisaged the change in climate which turned to warm and relatively dry probably attributable to the weak monsoon rainfall. The acceleration in human settlement during this phase is evidenced by Cerealia and by the increase of Melastoma, Ziziphus and Areca catechu implying forest clearance. [ABSTRACT FROM AUTHOR]

The main aim of the study is to assess the level of expectation and experience regarding the consideration of the skills relating to internal marketing in performance appraisal report while evaluating performance of human resources in Indian Oil Corporation Limited (IOCL) (AOD; Assam Oil Division), Digboi. This study also attempts to assess the level of expectation and experience regarding ideal 'post-performance-appraisal-scenario' in IOCL (AOD), Digboi. Furthermore, the study ventures to assess the level of overall satisfaction with performance appraisal system of the company as perceived by the employees, i.e. the internal customers. The study has looked into performance appraisal as a tool of human resource management through the lenses of internal marketing skills in the context of Central Public Sector Undertakings, which have very narrow base of internal Customers. This new approach has the potential to orient the Public Sector Undertakings to the market-driven economy. [ABSTRACT FROM AUTHOR]

A new species of the genus Badis Hamilton is described from Dibru River, Dibrugarh, Brahmaputra basin in Assam, India. The species has the following combination of characters: a conspicuous black blotch covering the superficial part of the cleithrum above pectoral fin base, a small oval-shaped black blotch on the middle of caudal fin, two predorsal bones, interorbital width 9.9-15.0, upper jaw length 6.1-6.9, lower jaw length 7.1-8.3 and orbital diameter 7.6-9.4 % SL. The species differs from its nearest congeners, B. badis, B. kanabos and B. tuivaiei by the absence of dark black or brown vertical bars on sides. A key to species of Badis of India is provided. [ABSTRACT FROM AUTHOR]

An assessment of human-elephant conflict was carried out in the fringe villages around Manas National Park, Assam during 2005-06. The available forest department conflict records since 1991 onwards were also incorporated during analysis. Conflict was intense in the months of July-August and was mostly concentrated along the forest boundary areas, decreasing with distance from the Park. Crop damage occurred during two seasons; paddy (the major crop) suffered the most due to raiding. Crop maturity and frequency of raiding were positively correlated. Single bull elephants were involved in conflicts more frequently (59%) than female herds (41%), while herds were involved in majority of crop raiding cases. Of the single elephants, 88% were makhnas and 11.9% were tuskers. The average herd size recorded was 8 individuals, with group size ranging up to 16. Mitigation measures presently adopted involve traditional drive-away techniques including making noise by shouting, drum beating, bursting fire crackers and firing gun shots into the air, and using torch light, pelting stones and throwing burning torches. Kunkis have been used in severe cases. Machans are used for guarding the crops. Combinations of methods are most effective. Family herds were easily deflected, while single bulls were difficult to ward off. Affected villagers have suggested methods like regular patrolling (39%) by the Forest Department officials along the Park boundary, erection of a concrete wall (18%) along the Park boundary, electric fencing (13%), simply drive away (13%), culling (11%) and lighting the Park boundary during night hours (6%). Attempts to reduce conflict by changing the traditional cropping pattern by introducing some elephant-repellent alternative cash crops (e.g. lemon and chilli) are under experiment. [ABSTRACT FROM AUTHOR]