A study on chaotic behaviour of equatorial/low latitude ionosphere over Indian subcontinent,using GPS-TEC time series

The deterministic chaotic behaviour of ionosphere, over Indian subcontinent falling under equatorial/low latitude region, ?0.3 to 22.19°N (geomagnetic), was studied using GPS-TEC time series. The values of Lyapunov exponent are low at Thiruvananthapuram and Agatti (?0.30 and 2.38°N, geomagnetic, respectively), and thereafter increase through Bangalore and Hyderabad (4.14 and 8.54°N, geomagnetic, respectively), and attain maximum at Mumbai (10.09°N, geomagnetic), which is near/at the edge of an anomaly crest. The values of correlation dimension computed for TEC time series are in the range 3.1–3.6, which indicate that equatorial/low latitude ionosphere can be described with four variables. Entropy values estimated for TEC time series show no appreciable latitudinal variabilites. The values of non-linear prediction error exhibit a trough, around the latitude sector, 4.14–16.15°N (Geomagnetic). Based on the values of the above quantifiers, the features of chaotic behaviour of equatorial/low latitude ionosphere are briefly discussed.     

Identification and fate of antibiotic residue degradation during composting and vermicomposting of chicken manure

Oxytetracycline (OCT) is a broad-spectrum antibiotic commonly used for broiler production to enhance growth and feeding efficacy. Concern has been expressed that the parent compounds of antibiotics such as OCT or their bioactive metabolites may be excreted through animal feces or urine with negative consequences for the environment when applied to agricultural lands. An integrated system involving a combination of thermophilic composting and vermicomposting using Eisenia fetida was investigated as a strategy for reducing the concentrations of oxytetracycline and its metabolites (4-epi-oxytetracycline [EOTC], α-apo-oxytetracycline [α-Apo-OTC] and β-apo-oxytetracycline [β-Apo-OTC]) in chicken manure. Treatments consisted of combinations of chicken manure and waste paper to produce waste mixtures with C: N ratios of 20, 30, 40, 50, 60 and 70 (T1, T2, T3, T4, T5 and T6, respectively). These were subjected to thermophilic composting for 20 days followed by vermicomposting with E. fetida for 7 weeks. The oxytetracycline concentration at the start of the experiment was in the range of 123.3–35.2 mg/kg, which reduced to 44–25.3 mg/kg after the thermophilic composting, and further reduced to 35.4–20.7 mg/kg at the end of the vermicomposting stage. The maximum overall percentage reduction of residual oxytetracycline in the final product was recorded in T3 (C:N ratio 40). The maximum percentage reduction of 84.3% was recorded in C: N ratio of 40 (T3) in which the metabolite degradation products were reduced to 3.1 mg/kg of 4-epi-oxytetracycline (EOTC), 3.9 mg/kg of α-apo-oxytetracycline (α-Apo-OTC) and 4 mg/kg of β-apo-oxytetracycline (β-Apo-OTC).     

Hydrogeology of Talwandi Sabo Tehsil,Bathinda District (Punjab): A remote sensing approach

Studies on water resources and hydrogeology of an area have become much easier with the help of Remote Sensing Technology. As an attempt to evaluate hydrogeology and ground water conditions of the tehsil Talwandi Sabo, Bathinda district, a hydromorphogeological map of the area was prepared through visual interpretation of satellite imagery. The study shows that the study area, a part of the Indo-Gangetic alluvial plain, is occupied by a large number of sand-dune complexes deposited by the ancient Satluj River while traversing the area during the past. Later on reworking of sand-dunes by aeolian action and their physical removal for agricultural purposes resulted in the present landscape of a plain land with sanddune complexes. Unconsolidated Quaternary alluvial sediments consisting of fine to medium-grained sand with admixture of kankar and some clay constitute the aquifer system of the area. Studies show that ground water occurs under both confined and unconfined conditions with water table at shallow depths. But the quality of the ground water is poor to marginal in most of the area except in the vicinity of main canal (Kotla Branch) where water seepage from canals has made the ground water good in quality.