U. K. Mandal

Bio: U. K. Mandal is an academic researcher. The author has contributed to research in topics: Remote sensing (archaeology) & Land use. The author has an hindex of 1, co-authored 1 publications receiving 15 citations.

Effects of Different Spatial Precipitation Input Data on Crop Model Outputs under a Central European Climate

Abstract: Crop simulation models, which are mainly being utilized as tools to assess the consequences of a changing climate and different management strategies on crop production at the field scale, are increasingly being used in a distributed model at the regional scale. Spatial data analysis and modelling in combination with geographic information systems (GIS) integrates information from soil, climate, and topography data into a larger area, providing a basis for spatial and temporal analysis. In the current study, the crop growth model Decision Support System for Agrotechnology Transfer (DSSAT) was used to evaluate five gridded precipitation input data at three locations in Austria. The precipitation data sets consist of the INtegrated Calibration and Application Tool (INCA) from the Meteorological Service Austria, two satellite precipitation data sources—Multisatellite Precipitation Analysis (TMPA) and Climate Prediction Center MORPHing (CMORPH)—and two rainfall estimates based on satellite soil moisture data. The latter were obtained through the application of the SM2RAIN algorithm (SM2RASC) and a regression analysis (RAASC) applied to the Metop-A/B Advanced SCATtermonter (ASCAT) soil moisture product during a 9-year period from 2007–2015. For the evaluation, the effect on winter wheat and spring barley yield, caused by different precipitation inputs, at a spatial resolution of around 25 km was used. The highest variance was obtained for the driest area with light-textured soils; TMPA and two soil moisture-based products show very good results in the more humid areas. The poorest performances at all three locations and for both crops were found with the CMORPH input data.

A plant-based extract mixture for controlling Spodoptera litura (Lepidoptera: Noctuidae)

Abstract: Spodoptera litura larvae are polyphagous insects that have become a significant pest in recent years. The spread of this pest has led to the continuous usage of insecticides on crops. Some plant extracts have been used as a mixture to control insect pests and improve productivity. A plant-based mixture was mixed at a ratio of 1:1 v/v to demonstrate the effect on contact toxicity, feeding (no-choice test), and enzyme activities on S. litura. The active compounds of P. retrofractum and A. calamus were isolated by preparative thin-layer chromatography (PTLC). Our results showed that binary mixtures from P. retrofractum and A. calamus exhibit the highest contact toxicity and antifeedant activity at a 1:1 ratio of LD30:LD10 dose (3.213 µg/larva P. retrofractum + 3.294 µg/larva A. calamus). The main active ingredient from each crude extract was (2E,4E,14Z)-N-isobutylicosa-2,4,14-trienamide from P. retrofractum, and beta-asarone and alpha-asarone from A. calamus. Additionally, A. calamus seems to be the synergistic compound. Some compound mixtures increased the glutathione-S-transferase activities in vivo; whereas, almost no significant differences in esterase activities were noted. The results indicated that the ethanolic crude extracts of P. retrofractum and A. calamus mixtures could be used as the pesticidal compound and to develop a binary mixture formulation for controlling lepidopteran pests. However, the toxicity of this mixture to mammals needed to be explored before commercial development.

Alansal dağilim özelli̇ği̇ gösteren i̇kli̇m parametreleri̇ni̇n coğrafi̇ bi̇lgi̇ si̇stemleri̇ i̇le beli̇rlenmesi̇ ve kullanim alanlari; genel bi̇r bakiş

Abstract: Gunumuzde hidroloji, tarim, ekoloji, orman yonetimi, meteoroloji vb. bircok farkli disiplinde yurutulen calismalarda degisik iklim parametreleri kullanilmaktadir. Dogru iklimsel veriler ancak noktasal olarak, meteoroloji gozlem istasyonlarinin bulundugu yerlerden elde edilebilmektedir. Oysaki bircok calismada alansal dagilim ozelligi gosteren iklim parametrelerine ihtiyac duyulmaktadir. Bu yuzden gunumuzde, noktasal gozlem degerlerinden faydalanarak alansal dagilim ozelligi gosteren iklim veri katmanlarinin uretilmesine yonelik ihtiyac ve ilgi giderek artis gostermektedir. Konumsal veri tabani uygulamalarinin vazgecilmez bir parcasi olan Cografi Bilgi Sistemlerinin (CBS) iklim calismalarinda kullanilmasi kacinilmaz bir hal almistir. Bu calismada, giderek artan talepler karsisinda alansal dagilim ozelligi gosteren iklim veri katmanlarinin CBS kapsaminda uretilmesine ve kullanim imkanlarina genel bir bakis getirilmeye calisilmistir