eChapters

Introduction

Drought is the most common adverse environmental factor which limits crop production in different parts of the world. Often drought is accompanied by relatively high temperatures, which promote evapotranspiration, and hence could accentuate the effects of drought and thereby further reduce crop yields. Since these events occur more frequently in tropical and semitropical regions where most of the developing countries are situated, droughts are often associated with food shortages and an overall setback to developmental activities. Therefore, raising of drought-resistant crops is common sense to achieve stability in production and to enhance the possibility of self-suficiency in food. Consequently, breeding for drought resistance is a major objective of many research programmes in the international and national institutions. This has been so for the past several decades. But, it is disappointing that, there has not been any measurable success in these programmes compared with the success achieved in breeding for yield; or breeding for disease resistance or breeding for quality attributes. In fact, this was amply expressed by Arnon (1980) when he stated “Breeding for drought resistance has been a consistent theme for as long as I remember and probably the greatest source of wasted breeding efforts in the whole field of plant breeding.” However, the fact remains that we do hear of drought resistant varieties in many crops. For example, C-306 in wheat, Lalnakanda in rice and M 35-1 in Sorghum are some of the better known examples in India. It is also claimed that a large number of cultures among the Assam Rice Collection exhibit a considerably high degree of drought tolerance. Many land races and wild relatives of several crop species are said to contain drought resistant traits, which could be profitably utilised in breeding programmes. This situation is not unique to India alone but is a common experience in different parts of the world. However, to afirm a conviction a short questionnaire to assess the current state-of-art on breeding for drought resistance was distributed to 75 distinguished plant breeders and plant physiologists all over the world. The questionnaire and a summary based on the responses is as follows:

Expression of genetic potential for growth and yield of a crop variety is directly dependent upon the environment comprising both climate (weather) and soil components. As discussed in the preceding chapter, the term ‘salt-affected soils’ encompasses a broad group of adverse but distinct soil conditions, namely, saline, alkali (sodic) and acid soils with further variations such as coastal and inland locations as well as arid and water-logged situations (Swaminathan 1977; Bresler et al. 1982). Factors limiting growth and yield of crop plants in various categories of problem soils are different and specific. Likewise, adaptive strategies evolved by plants to cope with the prevailing edaphic stresses, such as salt stress, also vary a great deal as indicated in Table 1. It is not unexpected therefore, that even varieties within a crop often show notable differences regarding tolerance to adverse soil conditions (Epstein et al. 1980; Devine 1982; Shannon 1984; Sayed 1985). Hence, it is essential that the breeder must understand the inherent charaderistics of the problem soil with which he is concerned and should also simultaneously appreciate that basically it is the sensitivity of crop variety, rather than the soil parameters per se, that essentially determines the occurrence as well as the magnitude of actual soil problem (Rana 1977). Since the degree of tolerance (adaptation) of crop varieties to different kinds of salt affected soils is genetically controlled, it is axiomatic that it can be improved through genetic manipulations by adopting suitable breeding procedures.

Introduction

Accumulation of excess soluble salts in the root zone of soils resulting in partial or complete loss of soil productivity is a worldwide phenomenon. The problems of soil salinity are widespread in the arid and semi-arid areas but salt-affected soils also occur extensively in the sub-humid and humid climates particularly in the coastal regions where the ingress of sea water through estuaries and rivers and through ground water movement causes large scale soil and water salinisation. Soil salinity is also a serious problem in areas where ground waters of high salt content are the only source of water available for irrigation. By far the most serious problems of salinity are being faced in the irrigated, arid and semi-arid regions of the world. Our ability to manage salt-affected soils and waters both in the irrigated and in the unirrigated regions will constitute a major effort in meeting potential food requirements. The magnitude of the problem can be appreciated from the following.

Abstract

The increase in human population, their growing economic activities and more and more transport demands, on one side, have increased the requirement of automobile fuels more than ever before, but the political turmoil in Middle east oil producing countries, the quick declination in stock of fossil fuels, the high rise in petroleum prices and rapid increase in air pollution due to automobile emission, on the other side, have made people of both developed and developing countries to search some non-polluting renewable but commercially viable alternative automobile fuel as a national priority. Hydrogen based fuel cells and latest designed improved storage batteries are knocking the door to bring revolution in developing non-polluted electric drive vehicles for 21st century. Successful blending of bio-diesel with petro-diesel has shown promising results to give relief to the present generation for saving some petroleum for future generation, for reducing air pollution substantially and for generating employment opportunity for its rural masses.

Abstract

Development of vermicomposting technology in India was started in seventies, but except some areas of South India it has not been popularized among common masses. This technology is labour intensive and needs attention to handle the tiny earthworms in a proper manner. Sincerity and dedication bring success while casual attitude ends up in financial loss. Lack of proper knowledge on suitable technique, unawareness about nutrient and hygienic standards of vermicompost, non availability of suitable earthworms, lack of marketing and training facility are some major problems in non-flourishing this technology in rural areas. But this technology being simple and easy to follow, is gradually becoming a boon to the low educated poor unemployed youths of the society for their economic development through generating income and creating self employment. Vermicompost, vermi-T and earthworms are marketable product. Government agencies and Non Government Organizations are trying to popularize this technology which has bright prospect to maintain health and hygiene of human to environment.

Abstract

Northeast is famous for its rich bio-diversity and Himalayan scenic beauty. Society is mainly agricultural based but the crop productivity is low in comparison to all India average. Major reasons are lacking of a). Improved cultivation technology at village or at farmers level, b). Agricultural inputs like high yielding seeds, chemical fertilizers and pesticides due to poor infrastructural facility, c). Land tenure system, etc. The agro climatic condition is very suitable to grow different types of vegetables round the year. Hilly areas offer a scope to grow certain vegetables as off-season vegetables and earn a high price. Northeast soils need application of nutrients for improving its productivity. Century old Jhoom cultivation technique, high soil erosions in hilly areas and regular floods in plains also play a vital role in developing reluctance among farmers in using costly chemical fertilizers. Profuse growth of vegetations e.g. grasses; weeds, jungles, etc. are noticed due to regular rainfall throughout northeast. Peoples usually burn these during clearing their fields and backyards for cultivation. These can be converted to good quality compost using vermicomposting technique and added to field for cultivation of different crops substituting chemical fertilizers. Experiments on cabbage, cauliflower, French bean, okra, onion and tomato showed that yield increased considerably with the application of compost in field.

Abstract

Abundant organic wastes come from agriculture sector. Earthworms offer an opportunity for beneficial disposal of this unwanted material by converting into vermi compost, a national wealth. It is rich in nutrients, enzymes, hormones and beneficial microbes but free from harmful chemicals and pathogenic microorganisms, hence improves crop productivity. Disposal through burning creates environment pollution and loss of valuable plant nutrients. Dumping creates unhygienic situation. Vermicomposting is quicker than other conventional composting techniques. In northeast India, Eisenia foetida and Perionyx excavatus were found equally efficient in vermi composting of agricultural wastes. Among different bio mass, vegetable wastes and soft weeds were converted to compost very quickly by using Perionyx excavatus within 1 to 2 months. Composting was found moderate (3 to 4.5 months) in crop residues and hardy weeds while slow (5 to 10 months) in case of dry tree leaves. When different wastes are mixed together it takes 3.5 to 4.5 months for complete composting. Composting can be accelerated by mixing the wastes with cellulolytic fungi such as Triichoderma viride, Trichurus spiralis, Paecilomyces fusiporus and Aspergillus awamori. Vermicompost prepared from wastes is a marketable product. It can bring prosperity in the villages by means of employment generation and good income. Awareness among people can be created through training.

Abstract

Organic farming, the state - of - art technology of the present era in agricultural cultivation, is not new to India. Green revolution in last four decades of Twentieth Century made farmers more dependants on chemical fertilizers and chemical pesticides for harvesting highest crop yield but side by side increased environmental pollution as well as health hazards and reduced soil productivity by increasing nutrient imbalance in soil. Indian farmers have almost forgotten their century old practice of preparation of compost from farm wastes and its use in next cultivation for getting pollution free healthy food materials. This articles deals with the problems of chemical farming in Indian context and their solution through organic farming.

Abstract

Solid waste, the creation of human being, is taken today the shape of a Demon to kill its creator by polluting breathing air, drinking water and essential food materials. It spreads different infectious killer diseases if not disposed off timely. Municipal authorities are spending lakhs of rupees to collect and transport solid wastes to dump-yard. Presence of both biodegradable and non-biodegradable wastes together in dustbin makes the disposal problematic and Municipal workers handling solid wastes suffer injury and disease infections. Municipal authority can clear about 50 percent of solid wastes either by dumping in low lying areas or by burning in open places causing unwanted environmental pollutions. Incinerations with electric producing facility, pyrolysis, dumping in properly built concrete landfills, Pelletization are scientific techniques for solid waste management. But recycling as resource materials is the best economical approach. Since non-biodegradable wastes can be sold to scrap dwellers for further processing it offers income opportunity. Biodegradable wastes can be converted to good quality vermicompost, which is also a marketable product and fetch good income. Different activities during recycling of solid wastes offer employment opportunities to literate & illiterate, skilled & unskilled, male & female, young & old workers. The present ‘Treatment at the end of pipe’ approach is to be changed by ‘Treatment at source’ approach.

Abstract

The toxic materials like arsenic, barium, beryllium, cadmium, chromium, lead, mercury, etc. present in Electronic wastes, in short e-wastes are a great threat to mankind since these contaminate soil, water and air of the surroundings. These E- wastes are mainly defective or obsolete parts of computers, audio-visual systems and electronic & electrical machineries used in the houses, offices and factories. These carcinogenic or hazardous toxic materials are root cause of damage of different parts of human body, untimely death as well as health disaster. Every year the manufacturers and assemblers produce around 1200 tons of electronic scraps in India. Collection of computer wastes from developed countries by greedy Indian business people for sorting out in India aggravates the environmental pollution. ‘Reduce, Reuse and Recycle’ are three important principles to be followed by one and all (Manufacturers, Distributors, Sellers, Buyers to Users) for proper scientific management of electronic wastes. Reverse osmosis, Electrolysis, Condensation, Electrolytic recovery, Filtration, Centrifugation, etc. are some of the important e-waste management technologies used to reclaim different toxic materials. Buyback policy should be made compulsory since Manufacturers can afford to build up infrastructure for reusing and recycling electronic wastes.  More and more use of bio-based plastics, toners, glues, inks will reduce the environmental pollution considerably and save the mankind from extinction.

Abstract

Beautiful Earth is the only planet of Solar system which supports life due to presence of water, air and favourable temperature. The surface atmosphere is warmed by absorption of solar ray due to green house effect, without which the average temperature of Earth’s atmosphere would have been –73^ºC and the ocean would have been frozen. Since the year 1850, when industrialization started in many countries, the concentration of different green house gases in the atmosphere have been increased remarkably (CO₂ – 34%, CH₄ – 145%, Fluorocarbons – 100%). Global warming, the increase in the average temperature of the Earth’s near surface air and oceans, is caused mainly due to increase in air pollution, green house gas generation and deforestation. Human activities are found more responsible for rapid global warming in last 50 years. Deadly storms, unbearable heat waves, high day-night temperature, Ice sheet melting in polar regions, glaciers receding at alarming rate, frequent wild fires in forest, coastal areas inundation, drinking water shortage and desertification are the serious impacts of global warming. It is a great concern to the Policy Makers to stop human activities responsible for global warming without jeopardizing technological development of society. Global warming has triggered the complex chain reactions : Increase in surface temperature – reduction in the permafrost and tundra areas.

5.1. Nature and role of soil enzymes
    General account
    Role in terrestrial ecosystems
    Role in aquatic ecosystems

5.2. Environmental conditions and microbial enzyme activity

4.1. Substrate quality
    Litter quality
    Soil organic matter (SOM) quality

4.2. Decomposer community
    Soil animals
    Soil microorganisms
    Terrestrial fungi
    Actinomycetes    
    Bacteria

3.1.Processes
                    
    Leaching                    
    Fragmentation/Comminution
    Catabolism                    
    Decomposition models
                
3.2. Patterns
                    
    Litter decomposition
    Root decomposition                    
    Limit values for decomposition            
    Decomposition pattern in ecosystems

2.1. The Physical environment
    Light
    Soil temperature
    Water dynamics

2.2. Chemical environment
    Production of phytotoxins

2.3. Biological environment
    Trophic dynamics
    Community structure
    Biodiversity

1.1. Characteristics and categories
                
1.2. Litter
    Patterns of accumulation
    Successional trends
    Seasonal variations
    Fluctuations in accumulation

1.3. Dissolved organic matter
    Sources of DOM
    Fluxes of DOM

1.4. Woody detritus

1.5. Soil organic matter

Appendix-'K'    :    Supreme Court Directions on School Safety
    
Case Study    :    Kumbakonam School Fire Tragedy

Appendix-'I'    :    Mock Drill Reporting Format
    
Appendix-'J'    :    Suggested Roles and Responsibilities of Stakeholders

Appendix-'H'    :    Do's & Don'ts During Commercial Nuclear Disasters