eChapters

In India rice is cultivated under two land situations. In uplands, rice is grown under rainfed conditions and the yield is normally low. In medium or low land conditions rice is grown under wet condition where plenty of rain water or irrigation water is available. Here an intensive tillage is practiced in wet to create a soft puddle condition and then paddy is transplanted. Land submergence is thus an essential condition for successful rice cultivation.

Rice soils are not necessarily soils with water at or near the surface. Many soils have a fairly deep water table, but their surface is kept under submergence maintaining depth of 3-5 cm water. This condition is maintained either by puddling when wet or by having a compacted layer in the sub surface.

A rice soil is characterized by reducing conditions, when it is cropped with rice during wet season and oxidizing conditions during dry season, when the land remained fallow or planted with dry season crops if, irrigation water is available.

Soil health

Soil health is defined as the continued capacity of soil to function as a vital living system, by recognizing that it contains biological elements that are keys to ecosystem function within land use-boundaries. These functions are able to sustain biological activity of soil, maintain the quality of air and water as well as promote plant, animal and human health.

The characteristics of a healthy soil depends on the physical, chemical and biological properties of soils which directly or indirectly influence crop production.

Soil quality and soil health are terms that are discussed in agricultural community. Both these terms encompass a complex, dynamic concept, different to define and hard to measure. The term soil quality and soil health are often used interchangeably in the scientific literature, with scientists in general preferring soil quality and producers preferring soil health. Soil health may be considered as the state of soil at a particular time equivalent to the dynamic properties in short term. In contrast, soil quality may be considered for a particular purpose over a longer time scale, equivalent to static soil quality. In a broader way soil quality may refer to both permanent and static soil properties. (Fig. 11.1).

A static soil property relates to natural characteristic of soil (texture) which are derived from pedogenic processes. These properties cannot be easily amended. The dynamic properties are readily related to management practices. The dynamic component is of most important for the growers because it allows the soil to come to its full potential.

Sustainable management of soil resources is essential for food, nutritional and economic security of the country. The continued degradation of soil resources is considered an important factor in lowering the total and partial factor productivity of agriculture in the country. The process like soil erosion, nutrient loss, water logging, desertification, acidification, compaction, crusting, salinization and soil contamination affect food and environmental security in most parts of the country. The future agricultural growth at higher rate cannot be sustained with a deteriorating soil resource base. We need to monitor the quality of soil resources and devise appropriate management strategies for sustainable crop production without deteriorating the environment.

In India, several agencies like National Commission on Agriculture (NCA), Ministry of Agriculture (Soil and Water conservation Division), Society for Promotion of Waste lands Development (SPWD), NBSS&LUP, Nagpur have been constantly inventorizing and characterizing soil resource for drawing up land use and development plans at National and State levels. However, there is a great variance in estimates due to differences in approaches and criteria for assessment. For an example,the total degraded land as estimated by NCA is 148.09 Mha as against, 175.0 Mha by Ministry of Agriculture (Soil and water conservation Division), 129.58 Mha by SPWD and 187.7 Mha by NBSS&LUP, Nagpur.

In soil profile development, we focused on vertical variability in soils - the differences among soil horizons. In this chapter we focused on horizontal variability- how soils differ from place to place across the landscape. Spatial variations in soil properties occurs across distances having geographic meaning for land management-from a few meters to many kilometers. We need to monitor regularly the status of our soil resources employing modern technologies to refine our understanding about them and renew our commitment to their preservation. The applications of Remote Sensing (RS), Geographical Information Systems (GIS) and Global Positioning System (GPS) have greater opportunities to offer in this regard.

Sustainable management of soil and water resources is essential for food, nutritional and environmental security of the country. The total and partial factor productivity of agricultures in India declined over years because of continued degradation of natural resources. The process leading to land degradation are generally triggered by excessive use of land and water resources to meet the growing demand of population for food, fibre and fodder. Various anthropogenic activities leading to accelerated land degradation through salinization, flooding, water logging, erosion of water and nutrients, drought reduced agricultural productivity and nutritional security in the country. These problems can be overcome by optimum utilization of land adopting suitable management practices. For effective land management practices, the soils should be interpreted in forms of their land capability, suitability for irrigation and crop growth. This will not only help the farming community and extension specialists, but also to the administrators and policy makers for using soils for sustainable agricultural production.

Trees are an integral and indispensable constituents of our natural surroundings. The trees keep the environment clean, make the soil healthy and provide food, fibre and shelter to mankind and wild animals. Trees help in stabilizing the soil, a vital natural resource, prevention of soil and water erosion, control run off water in the catchment areas, acts as a shelter belt against wind erosion in arid zone, act as a wind breaker to protect the coastal region during storm and cyclone besides contributing substantially to economic development. The National Commission on Agriculture stress the need for afforestation of about 40 million ha of land presently lying barren because of salinity, sodicity, waterloggings, ravines, coastal sandy areas, stony and gravelly lands, high altitude and slopping lands. Several agencies in various parts of the country are engaged in afforestation of these degraded lands.

Nitrogen ranks fourth element in cell composition after C, H and O. It forms main components of amino acids, the building blocks of peptides and proteins. Besides, it is present in the genetic material of cell as well as in the chlorophyll and cell wall in the form of chitin and mucopeptides. Plant growth in soil is often limited by less supply of nitrogen, therefore a major nutrient limiting factor in crop production. About 26 x 10⁶ Mg N is globally applied to soil each year to enhance crop productivity.

Data collection is a tedious and time consuming work, particularly from remote places. So many times the collected data is noisy. But data is the base for future planning and management of water resources. Planning based on noisy data could lead to failure. The modern data collection and subsequent control system i.e. telemetry and SCADA, are introduced in this chapter.

Modeling is heart of hydroinformatics. Simulation modeling became integrated part of modern science to justify feasibility of selected option among various competitive alternatives. Simulation modeling is a tool to evaluate the performance of a system, existing or proposed, under different configurations of interest and over long periods of real time. This chapter describes basic concepts, model simulation, model variables, modeling process, model performance etc. in brief.

Data mining is a powerful technology which helps in extracting future trends and behaviour from large databases. Thereby it helps decision makers to make knowledge-driven decisions. One common form of real-world data is time series. The suitable models are required to analyze time series data. This chapter provides a short introduction to stochastic system, uncertainty, basic statistics time series analysis and some stochastic models.

Mulching

The technique of covering the soil with plastic films or natural crop left over (residues) for soil and water conservations is called mulching.

This technique was practiced by farmers using dry leaves straw, trash, stones etc to conserve water. Presently plastic film have come into use for the purpose of mulching due to inherent advantages.

Fertility of a soil can be assessed by analyzing various available nutrients present in the soil. Fertilizer recommendations for various crops and cropping sequences can be made on the basis of fertility status of a soil. Besides this, problematic soil can be ameliorated on the basis of soil test values. Among the various steps of soil testing programmes, soil sampling is the most vital step.

1.0 Introduction

Population in dry lands of the world is increasing; more fresh water is required in order to meet the growing demands. To meet this challenging situation developing new technologies for identification of potential sites for rainwater harvesting (RWH) is an important step towards maximizing water availability in semi-arid areas.

The following graph is a visual representation of how plant growth and/or yield is affected by nutrient concentrations

Organic matter and its composition 
Decomposition  
Types microorganisms involved 
Enzymes involved in decomposition process?

    1.    Salt affected soils;
    2.    Classification of salt affected soils; 
    3.    Formation of salt affected soils; 

Alkali soil
 
Alkali soils are those that contain measurable amounts of soluble salts mostly as carbonates and bicarbonates of sodium. 

Definitions of IPNM 
Concept of IPNM 
Main objectives of INM 
Components of IPNM

Abstract

Radon being the radioactive daughter product of Uranium; the interrelationship between U and Rn has been established in the present study. It is found that Radon coexist with Uranium in the region. A total of 61 samples were collected spatially from hand pumps and bore wells of the study area. Major ions such as Ca²⁺, Mg²⁺, Na⁺, K⁺, F^-, Cl^-, HCO^3-, NO^3-, H₄SiO₄,PO₄- and SO₄^2- and U, Rn were analysed. The lithological influence of U and Radon occurrence is also highlighted. Hard rocks especially Granites are the source for both U and Rn in the study area whereas the lack of correlation exist between U and Rn in sedimentary terrain can be attributed to difference in flow conditions and chemical properties of these elements. 

Key words: Radon, Uranium, Granite, Ground water, Source.
 

Abstract

Quality of water is affected by natural and man induced contamination to groundwater system. Area chosen for study has gained its own importance due to the location of two lignite mines and a Thermal power plant in operation. Extensive large scale pumping of water is done for lignite mining. The mine drainage and drainage from thermal power plant along with agricultural return flow from lignite charged waters increases the severity of problem. In order to achieve a panacea for the above-mentioned situation, the study has incorporated and integrated in all related factors to get a meaningful interpretation for groundwater quality and quantity management in and around Neyveli area. The frequent failure of monsoon has added to the existing problem of over exploitation. To attain a panacea for water chemistry groundwater samples were collected for four different seasons. Higher EC and TDS values are observed in Southeast and Southwest part of the study area. In Southwest monsoon and Summer seasons HCO₃Cl dominates the anions, with few representations for SO₄. In Northeast monsoon and Post monsoon season Na + K – Ca + Mg is the dominant. Thermodynamic, studies reveal that groundwater of the region are stable with Kaolinite stability field in all the silicate systems. Bicarbonates derived from silicate mineral weathering are noted in the NW, Northern and in the mining region. These regions are located in the NW and NE part of the study area. Comparison of water quality to standards shows that the water can be used for drinking and for irrigation purposes except in few locations.

Methods of soil fertility evaluation          
    I.    Nutrient deficiency symptoms on plants  
    II.    Plant analysis
    III.    Biological tests   
    IV.    Soil testing
    V.    Spectral sensing for site specific evaluation