PREDICTIVE ASSESSMENT OF SEVERITY OF AGRICULTURAL DROUGHTS BASED ON AGRO-CLIMATIC FACTORS1

ABSTRACT: Past historical evidence indicates that droughts have had great impacts on human life. Drought (or scarcity of water) is assessed based on two key factors, namely, the estimated water demand, and the expected water supply. The formulation of these key factors for a region largely depends on the agro-climatic and economic conditions. Consideration of one such key factor is the relationship between the crop yield and water deficit in the assessment and prediction of agricultural droughts. The varying nature of this relationship from crop to crop adds to the complexity of agricultural drought analysis. To overcome this difficulty in analyzing agricultural droughts of a region, it is adequate to consider and place emphasis on a single crop (i.e., an index crop) grown homogeneously over the major area of the region. From one year to another year, the pattern of water requirement during the growing season of an index crop is rather stationary, and the water supply in arid and semi-arid area is mainly from seasonal random precipitation. In a region, grain yield of the index crop and, in turn, assessment of the severity of drought can reasonably be predicted as a function of the time of crop sowing and the distribution of rainfall, provided that temporal and spatial effects of other contributing factors (crop variety, soil fertility status, crop disease, pest control, cultivation practices etc.) on grain yield are considered to be uniformly distributed (i.e., stable). A predictive method of assessing agricultural droughts in an arid area of western India is presented. The major crop (Pearl Millet) of this region is grown from. July through September. The formulation of the proposed predictive method inherently implies that the grain yield of the main crop is a reliable indicator of agricultural drought. In the development of this predictive relationship (i.e., a regression type model) a number of potential yet simple variables affecting the grain yield in the region were investigated. The soil moisture index, although generally considered significant compared to the simple variables, has been found to account for insignificant variation in the grain yield. Results of our investigations suggest that it would be advisable to exclude the soil moisture index variable from the model. The proposed regression model can be used in the prediction of grain yield of the main crop several months ahead of crop harvesting operations and, in turn, the assessment of agricultural drought severity as mild, moderate, or severe. Such an assessment is expected to be helpful to planners for arranging appropriate measures to effectively combat agricultural drought situations.     

Detection of chlorophenolics in effluents from bleaching processes of rice-straw pulp

A number of chlorinated derivatives of phenols, catechols, guaiacols, syringaldehydes, have been detected and their concentrations estimated, using gas chromatography in the chlorination (C) and extraction (E) stage of spent bleach liquor generated in the laboratory by bleaching rice-straw soda pulp. The concentration of various compounds detected have also been compared with their reported 96LC50 values.     

Book reviews

Local Politics and Participation in Britain and France

Albert Mabileau, George Moyser, Gerraint Parry, Patrick Quantin. 1989. 281 pp. Price £30.00.

ISBN: 0 521 34576 6.

The Rural State?: Limits to Planning in Rural Society

Paul Cloke and Jo Little. 1990, Oxford University Press. 287 pp.

Price £30.00.

ISBN: 0 19 823287 X

Urbanisation in History: A Process of Dynamic Interactions. International Studies in Demography.

Edited by Ad van der Woude, Jan de Vries, and Akira Hayami. Clarendon Press, Oxford, 1990. 371 pp. Price £40.00.

Housing and Social Inequality

Jenny Morris and Martin Winn

Integrated Land‐Use and Transport Modelling — Decision Chains and Hierarchies

Tomas de la Barra

Beyond Green Belts — Managing Urban Growth in 21st Century

Regional Studies Association (1990). 64 pp. Price £9.95.

Learning from Rotterdam

M. J. Vroom and J. H. A. Meeus.

173 pp. Nichols, New York. Price £25.

Reviewing the Quality of Environmental Statements

N. Lee and R. Colley

EIA Centre, University of Manchester, 1990.

Occasional Paper 25, 46 pp. Price: £3.00.

Knowledge and Public Policy: the search for meaningful indicators

Judith Innes. Transaction Publishers, New Brunswick. 352 pp. Price: £16.95.

Urban Problems: An Applied Urban Analysis

Michael Pacione. Routledge, 1990.

Living with Inner City Policies: Two Essays on Inner City Life and Inner City Policies

Meryl Aldridge and John Edwards, Department of Social Policy, Royal Holloway and Bedford New College. Social Policy Papers No. 2, 1989.

Information Technology in Geography and Planning: including principles of GIS

Bracken and Webster, Routledge, London 1990. 444 pp.

Housing and Social Change in Europe and the USA

Michael Ball, Michael Harloe and Maartje Martens. Routledge, 222 pp. Price: £10.99.

Land and Property Development: Changing Context

Edited by Healey and Nabarro. 212 pp. Price: £39.50.     

Win-win opportunities and environmental regulation: testing of porter hypothesis for Indian manufacturing industries

This paper studies the effect of environmental regulation on the productive efficiency of water polluting industries in India. The panel data of 92 firms belonging to sugar industry of India during the period 1996-99 are used to test the Porter hypothesis of having win-win opportunities for the firms subjected to the regulation. The main empirical result is that the technical efficiency of firms increases with the degree of compliance of firms to the environmental regulation and the water conservation efforts there by supporting the Porter hypothesis.     

The volatilisation and sorption of (129)I in coniferous forest,grassland and frozen soils

129I is a potentially important radionuclide in safety assessments of proposed deep geological radioactive waste repositories due to its radiotoxicity, high mobility and long physical half-life (15.7 million years). In soils, iodine is present both in an inorganic form and in organohalide complexes, some of which are volatile under natural environmental conditions.This study has examined volatilisation, sorption and the effect of freezing on sorption and loss of (125)I (physical half-life 60.2 days), as a surrogate for (129)I, within coniferous forest and grassland soils. The results do not suggest that volatilisation from these soils is a significant pathway for the transport of (129)I. Strong and specific sorption of iodine to humic substances has been demonstrated, which is reduced at freezing temperatures. It is hypothesised that rapid sorption to soil humic substances can significantly reduce volatilisation rates. The effect of freezing conditions on iodine extractability from soils suggests a microbially mediated sorption process.     

Comparison of gravimetric and gas chromatographic methods for assessing performance of textile materials against liquid pesticide penetration.

Penetration of liquid pesticides through textile materials is a criterion for determining the performance of protective clothing used by pesticide handlers. The pipette method is frequently used to apply liquid pesticides onto textile materials to measure penetration. Typically, analytical techniques such as Gas Chromatography (GC) are used to measure percentage penetration. These techniques are labor intensive and costly. A simpler gravimetric method was developed, and tests were conducted to compare the gravimetric and GC methods of analysis. Three types of pesticide formulations and 4 fabrics were used for the study. Diluted pesticide formulations were pipetted onto the test specimens and percentage penetration was measured using the 2 methods. For homogeneous formulation, the results of the two methods were fairly comparable. However, due to the filtering action of the textile materials, there were differences in the percentage penetration between the 2 methods for formulations that were not homogeneous.     

Subsampling program for the estimation of fish impingement

Federal regulations require operators of nuclear and coal-fired power-generating stations to estimate the number of fish impinged on intake screens. During winter months, impingement may range into the hundreds of thousands for certain species, making it impossible to count all intake screens completely. We present graphs for determinig the appropriateoptimal subsample that must be obtained to estimate the total number impinged. Since the number of fish impinged tends to change drastically within a short time period, the subsample size is determined based on the most recent data. This allows for the changing nature of the species-age composition of the impinged fish. These graphs can also be used for subsampling fish catches in an aquatic system when the size of the catch is too large to sample completely.     

Oceanographic Studies off Beypore Port, West Coast of India to Locate a Dredge Dumping Site

This study presents the salient results of the oceanographic investigations carried out along the west coast of India to locate a dumping site for the dredged material generated from the capital of the proposed development of the all weather port. Based on the results of movement of disposed material obtained from a 2 dimensional coastal circulation model and considering the possibility of having a navigational channel later on in line with the port, a dumping site is recommended at the 15 m water depth contour with coordinates: Latitude 11 degrees 07.00'; Longitude 75 degrees 45.60', where the environmental impacts on the ecosystem due to dumping operations is considered to be minimum.     

Assessment of the radiological impacts of historical coal mining operations on the environment of Ny-Alesund, Svalbard

Mineral extraction activities, such as those conducted by oil, gas and coal industries, are widespread throughout the Arctic region. Waste products of these activities can result in significant contributions to the radioactive burden of the surrounding environment due to increased concentrations of naturally occurring radioactive materials (NORM) to levels that would not normally be found in the environment. Coal mining operations commenced in the early 1900s on Svalbard and have been conducted at a variety of locations on the archipelago since then. Coal contains radionuclides of the uranium and thorium series as well as 40K. Extraction and processing of coal can result in releases of these radionuclides to the broader environment with subsequent impact on the human and non-human inhabitants of the area. This paper presents the results of a study on environmental radioactivity resulting from historical coal mining operations conducted at Ny-Alesund, Spitsbergen, in the Svalbard archipelago. Activity concentrations of radionuclides found in materials associated with these operations are presented as well as the results of a spatial dosimetric survey conducted over an area affected by coal mining.     

Rural energy transitions in developing countries: a case of the Uttam Urja initiative in India

In most developing countries, at the household level, traditional burning of biomass or use of inefficient technologies for domestic applications like lighting is common, triggering concerns related to fuel or technology switching. The paper focuses on opportunities to promote cleaner energy options through development of value chains delivering improved energy efficiency and access in developing countries. We discuss the example of Uttam Urja, a field project involving the dissemination of photovoltaic lighting technologies in rural areas of India. We focus on the challenges of introducing radical innovations into the residential energy sector in developing countries. For the purpose of this paper the Uttam Urja project is conceptualized as an ‘experiment’ and analysed using the Strategic Niche Management (SNM) framework. The paper emphasizes that to effect socio-technical transitions to clean energy options on the ground, it is desirable to focus on technology customization and innovative financing to cater to the needs and concerns of end users.