Small Mammal Abundances in a Grassland and Forest Area at the Lake Fayetteville Environmental Center, Arkansas

We examined changes in abundance of small mammals in forest and prairie-grassland habitat at Lake Fayetteville, Arkansas over a period of 32 years. We estimated the population size of small mammals using a mark-recapture method by capturing small mammals employing rat-sized Sherman live traps laid out in a grid with 8 rows of traps, 15 traps per row, 9.14 m (30 feet) between traps and rows covering an area of 1.01 ha (2.5 acres) in size. Six species of mammals were trapped in the prairie-grassland and three species were captured in the forest habitat. In the forest, the white-footed deermouse (Peromuscus leucopus)was greatest in 1998 and in 2006. In the prairie-grassland, the population of hispid cotton rats (Sigmodon hispidus) were greatest in 2004, 2008, 2010 and 2014 and have increased over the years with the change in grass composition. The prairie-grassland in 1962 was mainly a broomsedge bluestem (Andropogon virginicus) field but as time progressed more and more prairie grasses invaded helped by controlled burns and removal of the invading eastern red cedars (Juniperus virginiana). The population of Sigmodon hispidus was weakly correlated with the minimum winter temperatures from the previous year

Mesoscale convection system and occurrence of extreme low tropopause temperatures: observations over Asian summer monsoon region

The present study examines the process of how tropospheric air enters the stratosphere, particularly in association with tropical mesoscale convective systems (TMCS) which are considered to be one of the causative mechanisms for the observation of extremely low tropopause temperature over the tropics. The association between the phenomena of convection and the observation of extreme low tropopause temperature events is, therefore, examined over the Asian monsoon region using data from multiple platforms. Satellite observations show that the area of low outgoing long wave radiation (OLR), which is a proxy for the enhanced convection, is embedded with high altitude clouds top temperatures (&le;193 K). A detailed analysis of OLR and 100 hPa temperature shows that both are modulated by westward propagating Rossby waves with a period of ~15 days, indicating a close linkage between them. The process by which the tropospheric air enters the stratosphere may, in turn, be determined by how the areas of convection and low tropopause temperature (LTT) i.e. <I>T</I>&le;191 K are spatially located. In this context, the relative spatial distribution of low OLR and LTT areas is examined. Though, the locations of low OLR and LTT are noticed in the same broad area, the two do not always overlap, except for partial overlap in some cases. When there are multiple low OLR areas, the LTT area generally appears in between the low OLR areas. Implications of these observations are also discussed. The present analysis also shows that the horizontal mean winds have a role in the spatial distribution of low OLR and LTT

Integrated nutrient management for sustaining wetland rice (Oryza sativa) production in mid hills altitude of Meghalaya

A field experiment was conducted, during rainy season of 2007 and 2008 at the research farm of ICAR Research Complex for NEH Region, Umiam, Meghalaya, to study the effect of organic and inorganic sources of nutrients in wetland rice. The results of two years study reveals that the growth parameters were improved with application of 5 tonnes/ha FYM + Azolla dual cropping + 75 per cent of the recommended dose of NPK (80:60:40 kg/ha, RDF). While higher yield attributes were recorded with 50% of the recommended dose of fertilizer in the presence of FYM 5 tonnes/ha + Azolla dual cropping resulted into maximum grain yield of 39.34 q/ha, which was 13.89% and 16.87% higher over alone application of recommended dose of NPK and bio-organics, respectively. Application of FYM 5 tonnes/ha + Azolla + Azospirillum found to produce grain yield equal with FYM 10 tonnes/ha and application of recommended dose of NPK without any bio-organic. The use of Azospirillum was promising in improving growth and yield of rice. The grain yield of rice recorded with FYM 5 tonnes/ha + seedling inoculation with Azospirillum in the presence of 75% recommended dose of NPK (38.34 q/ha) was significantly higher over that of 50% RDF with same bio-organics, but when Azolla dual cropping in place of Azospirillum was adopted, the maximum grain yield was recorded with 50% RDF, which was however, at par with that of 75 and 100% RDF applied together with same bio-organics, indicated that the use of biofertilizer can save 25-50 per cent of the recommended dose of NPK, besides substantial improvement in grain yield of wetland rice. The uptake of K was more than N and P. Maximum N and P uptake was recorded with FYM 5 tonnes/ha + Azolla dual cropping + 75 RDF, while maximum K uptake was recorded with the same bio-organics applied in the presence of 100 RDF. Highest net return with benefit : cost ratio was found with FYM 5 tonnes/ha + Azolla dual cropping + 50 RDF

Enhanced Room Temperature Coefficient of Resistance and Magneto-resistance of Ag-added La0.7Ca0.3-xBaxMnO3 Composites

In this paper we report an enhanced temperature coefficient of resistance (TCR) close to room temperature in La0.7Ca0.3-xBaxMnO3 + Agy (x = 0.10, 0.15 and y = 0.0 to 0.40) (LCBMO+Ag) composite manganites. The observed enhancement of TCR is attributed to the grain growth and opening of new conducting channels in the composites. Ag addition has also been found to enhance intra-granular magneto-resistance. Inter-granular MR, however, is seen to decrease with Ag addition. The enhanced TCR and MR at / near room temperature open up the possibility of the use of such materials as infrared bolometric and magnetic field sensors respectively.Comment: 22 pages of Text + Figs:comments/suggestions([email protected]

Production potential of baby corn (Zea mays) on raised bed in waterlogged lowland rice fallow in North East India

A field experiment was conducted during rainy (Kharif) season of 2008-09 and 2009-10 at research farm of ICAR-Research Complex of NEH Region of Umiam, Meghalaya, to study the production potential of baby corn (Zea mays L.) as influenced by raised bed height in waterlogged low land area and nitrogen levels. Taller plants with more number of leaves were recorded with 50 cm height of raised bed. The days to harvest initiation and harvest duration were more at 50 cm height of raised bed. The barrenness in baby corn was also comparatively lesser with 50 cm height of raised bed. The maximum baby corn and fodder yield was recorded with 50 cm height of raised bed, which were 11.3 and 10.7% higher than 40 cm height of raised bed. Further, decrease in height of raised bed up to 30 and 20 cm markedly reduced babycorn yield as compared to 50 cm height of raised bed. The nitrogen content and uptake, protein yield, nitrogen use efficiency and economical parameters were also higher at 50 cm height of raised bed. Increasing nitrogen level produced taller plants with more number of leaves. The harvest initiation decreased by 4 days while harvest duration was increased by 4 days with 120 kg N/ha. The barrenness declined with increasing nitrogen levels. The highest baby corn yield, nitrogen uptake and protein yield were recorded with 80 kg N/ha. Increasing nitrogen levels progressively reduced agronomic N use efficiency and physiological efficiency of nitrogen, but apparent recovery increased up to 80 kg N/ha. The gross, net return and benefit: cost ratio were higher with 80 kg N/ha. Therefore, for getting higher yield and net return, the baby corn should be grown at 50 cm height above the moisture level on raised bed and fertilized at the rate of 80 kg N/ha

Circuits for Optical Based Line of Sight Voice Communication

We present here line of sight communication between a person and his neighbour with the help of optical signal produced by a laser torch which act as a carrier. It is therefore a wireless communication and the transmission can go up to 500 meters. We used photodiode to receive the signal at the receiver. The transmitter circuit comprises condenser microphone transistor amplifier BC547 followed by an op-amp stage built around µA741. When we give a voice signal from the mike, it converts the voice signal into the electrical signal. This electrical signal is fed to IC741 (op-amp) for amplification. The gain of the op-amp can be controlled with the help of 1-mega-ohm potentiometer. The AF output from IC is coupled to the base of a class B amplifier which, in turn, modulates the signal. The transmitter uses 5V power supply. However, the 3-volt laser torch (after removal of its battery) can be directly connected to the circuit-with the body of the torch connected to the class B. The photodiode converts the optical signal into electrical signal and again this signal is amplified using IC741 and a combination of class B push pull amplifiers. The receiver circuit uses an NPN photodiode as the light sensor that is followed by a two-stage transistor preamplifier and IC741 based audio Power amplifier. The receiver does not need any complicated alignment. Just keep the photodiode oriented towards the remote transmitter's laser point and adjust the volume control for a clear sound. The sensor must not directly face the sun

Soil Quality Parameters and Carbon Stock as Influenced by Fodder Grasses and Organic Amendments in an Alfisol of Northeastern India

Intensive tillage, cultivation along the slope, low input, minimal nutrient replacement and high rainfall are among major causes of land degradation in the north eastern hill (NEH) region (Ghosh et al. 2009). Maintaining and enhancing soil quality are crucial to sustaining agricultural productivity and environmental quality (Lal, 2004). Continuous cropping, without use of conservation-effective measures, has negative effects on the soil and environment (e.g., loss of SOC, soil erosion, water pollution). Thus, soil management methods are needed that enhance use efficiency of inputs, reduce losses and minimize adverse impacts on the environment (Bilalis et al. 2009). Perennial grasses provide year- round ground cover, which reduces run-off and soil erosion from sloping land (Ghosh et al. 2009). Cultivation of forages in degraded and sloping lands not only supply green palatable fodders to livestocks but also rehabilitates the degraded soils by improving physico-chemical properties. Forages have strong root systems compared to field crops (such as rice, maize etc.), protect soil and improve aggregation (Ghosh et al. 2009). Soils under perennial grasses and those which are undisturbed for a long time are potential C sinks because the grasses add organic matter (OM) to soils through root growth, and decline in OM decomposition because of lack of tillage. Further, conversion of degraded cropland soils to forages and perennial grasses lead to C sequestration (Grandy and Robertson, 2007). Thus, present investigation was conducted with the objective to assess the impact of perennial forage grasses and organic amendments on soil properties and C-sequestration potential

Growth of dense CNT on the multilayer graphene film by the microwave plasma enhanced chemical vapor deposition technique and their field emission properties

Catalyst assisted carbon nanotubes (CNTs) were grown on multilayer graphene (MLG) on copper and silicon substrates by the microwave plasma enhanced chemical vapor deposition technique. The transmission of the MLG was found to vary between 82 to 91.8% with the increase of deposition time. Scanning electron microscopy depicted that the MLG film survived at the deposition condition of CNTs with the appearance of the damaged structure due to the plasma. Growth of CNTs was controlled by adjusting the flow rates of methane gas. The density of carbon nanotubes was observed to increase with a higher supply of methane gas. It was observed that the field emission properties were improved with the increased density of CNTs on MLG. The lowest turn-on field was found to be 1.6 V mu m(-1) 1 accompanied with the highest current density of 2.8 mA cm(-2) for the CNTs with the highest density. The findings suggested that the field emission properties can be tuned by changing the density of CNTs