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All civil engineering projects start with soils, however not all soils have the best qualities for building. Engineers deal with "problematic soils" in many places of the world, which are those that present difficulties for the design, building, and long-term performance of structures because of their distinct mechanical, chemical, or physical characteristics. These soils can be very compressible, have low shear strength, swell or shrink, or collapse when wet. For infrastructure development to be safe and sustainable, these issues must be recognized and addressed. With an emphasis on problem soils, submerged soils, micronutrients, and heavy metals, this textbook on "Reclamation and Management of Problematic Soils" is based on my research and teaching experience in soil chemistry, fertility, and plant nutrition. incorporating arsenic into farming practices. The target audience for this book is B.Sc. (Ag). The revised ICAR syllabus serves as the basis for this. Students studying environmental sciences and related fields of agriculture, however, might also gain from it. The book is structured into fourteen chapters, each of which focuses equally on a different topic pertaining to agricultural research in India. The chapters in this book cover the entire course and are arranged chronologically, making it simple for beginning agricultural students to understand. The treatment of various problem soil types and economical bioremediation techniques employing multiple tree species (MPTS) are covered in this article. Undergraduate agriculture students can gain from this thorough examination of flooded soils, saline irrigation water utilization, and soils influenced by acid, acid sulfate, and salt. Damaged sites and waste management concerns were also taken into account. This book focuses on using Geographic Information Systems (GIS) and Remote Sensing (RS) to monitor and assess degraded lands, irrigation water, and problematic soils. The purpose of this textbook is to meet the demands of instructors and undergraduate agriculture students at different Indian agricultural universities. Any recommendations for enhancement would be much appreciated. My profound appreciation goes out to my coworkers, students, and the other geotechnical specialists whose knowledge and experiences have influenced the material in this book. I hope that this work will be used as a practical reference and a foundational text for anyone who deal with the particular difficulties of building on troublesome soils.

Introduction Managing the diverse array of stresses confronting cultivated lands stands as a pressing necessity within the agricultural domain, demanding swift adaptability to navigate shifts and satisfy evolving requisites along the production-consumption continuum. In India, approximately 7.0 million hectares of agricultural terrain grapple with salt-related predicaments, a figure poised for escalation owing to factors like secondary salinization in irrigation networks, amplified dependence on substandard water reservoirs in arid and semi-arid locales, and the complexities posed by phenomena such as sea water encroachment and brackish water aquaculture in coastal regions. Forecasts indicate a potential expansion of salt-affected soil regions in India to encompass roughly 13 million hectares by the year 2025. Within this landscape of challenges, agronomists shoulder a pivotal responsibility, entrusted with the mandate of bolstering productivity via pioneering research endeavors and the formulation of holistic strategies. This undertaking necessitates a nuanced comprehension of salt-affected soils, coupled with the crafting of contingency blueprints predicated upon resourceefficient, economically sound, and ecologically sustainable methodologies. Given the flux in climatic patterns, the adoption of proactive measures assumes heightened significance. Scholarly discourse, exemplified by Singh’s seminal work in 1998, furnishes a retrospective lens on the saga of salt-affected soils. Building upon this historical scaffold, the present exposition endeavors to trace the trajectory of agronomic inquiry spanning epochs ranging from the Vedic era through pre-independence and post-independence epochs. By spotlighting the seminal contributions of researchers in tackling salt-induced soil adversities, the paper endeavors to underscore the profound ramifications of such endeavors on societal wellbeing and environmental equilibrium. Soil Salinity in Ancient India: Pre- and Post-Vedic Perspectives Landforms and landscapes emerge from the weathering of rocks and minerals, incorporating salts as essential constituents. These salts have been present

Introduction Soil quality is a critical concept in environmental science, agriculture, and land management. It refers to the ability of soil to perform its essential functions, which include supporting plant growth, regulating water flow, cycling nutrients, filtering pollutants, and providing habitat for microorganisms. Healthy, high-quality soil is fundamental for the productivity of ecosystems and the sustainability of agricultural practices. The quality of soil is influenced by a combination of physical, chemical, and biological factors. These include soil texture, structure, organic matter content, pH, nutrient availability, and the presence of beneficial organisms like bacteria and fungi. When these factors are balanced, soil can support healthy crops and ecosystems. However, soil degradation—caused by practices such as overuse of chemical fertilizers, deforestation, erosion, and pollution—can severely reduce its quality, leading to lower agricultural yields, water contamination, and loss of biodiversity. Assessing soil quality involves monitoring several key indicators, such as organic matter levels, soil texture, compaction, water infiltration rates, and the presence of key nutrients. Organic matter is especially important, as it helps to bind soil particles, retain moisture, and provide a food source for beneficial microorganisms. The chemical aspect of soil quality is equally vital, encompassing the availability of nutrients such as nitrogen, phosphorus, and potassium, as well as the presence of any harmful contaminants like heavy metals. The biological dimension of soil quality relates to the diversity and activity of organisms within the soil. A rich microbial community enhances nutrient cycling, helps decompose organic matter, and promotes plant health. Earthworms, for instance, play a critical role in aerating the soil and facilitating water infiltration. Soil quality is not a static property; it can change over time depending on land management practices. Sustainable practices such as crop rotation, conservation tillage, the use of organic amendments, and maintaining ground cover can improve and maintain soil quality. Conversely, unsustainable practices like excessive tillage, monoculture, and the overuse of agrochemicals can degrade soil, making it less productive and more prone to erosion. In

Introduction Salt-affected soils (SAS) can be found across different latitudes, exhibiting variations in morphology, biology, and chemical, physical, and physicochemical properties (Gupta and Gupta, 2017). Despite their diversity, SAS share a common characteristic: the dominant role of soil solution electrolytes in the soil formation process, leading to properties that create unfavorable conditions for the normal growth of most plants (Szabolcs, 1989). In cases where SAS develop due to natural geomorphological processes, certain plant species, known as halophytes, have evolved specialized physiological adaptations to survive in these environments. Halophytes are capable of thriving in highly saline habitats by effectively managing the stress caused by excessive salt. Plants growing in such conditions employ various adaptive mechanisms to tolerate and flourish despite the salinity challenge. Salt-affected soils (SAS) require specialized management strategies to mitigate the challenges posed by high salinity levels. Plants and organisms in these ecosystems have evolved various adaptations to manage salt levels, such as developing specialized root structures, eliminating or containing excess salt, and efficiently absorbing water and nutrients (Flowers and Colmer, 2015). Despite their typically low alpha-diversity, SAS ecosystems contribute significantly to beta-diversity due to the specialization of organisms that thrive in such challenging environments. However, many of these high-value ecological systems have been severely degraded worldwide as a result of various political and economic decisions. For example, mangroves in countries like Thailand, Vietnam, Mexico, and Ecuador have been destroyed to make way for shrimp farming (FAO, 2007). Sabkhas around the Mediterranean coast have suffered from overexploitation of the aquifers that sustain them, and the reduction of water flow to closed drainage basins, such as in the case of the Aral Sea, has occurred due to water being diverted for irrigation, especially for cotton farming. Further degradation is seen in the transformation of SAS wetlands into agricultural fields through drainage, a practice observed in many regions (Mitsch and Gosselink, 2007). These ecosystems, once considered wastelands

Introduction In India acid soils occur in the high rainfall areas covering about 25 million hectares of land with a pH below 5.5 and 23 million hectares of land with a pH between 5.6 and 6.5. In India, acid soils occur in Assam, Meghalaya, Arunachal Pradesh, Mizoram, Nagaland, NEFA, Manipur, Tripura, West Bengal, Bihar, Uttar Pradesh, Himachal Pradesh, Jammu and Kashmir, MP, Maharashtra, Kerala, Karnataka, Tamil Nadu and Andhra Pradesh. Punjab, Haryana, Rajasthan and Gujarat are the only states in India where acid soils do not occur. Soil acidity is a limiting factor affecting the growth and yield of many crops all over the world. The basic problems concerning chemical properties of more acid soils are, besides acidity itself, the presence of toxic compounds and elements, such as soluble forms of Al, Fe and Mn, nitrites and various toxic organic acids. Aluminium (Al) toxicity is one of the major constraints on crop productivity on acid soils, which occur on up to 40% of the arable lands of the world. Al is the third most abundant element in the earth’s crust and is toxic to plants when solubilised into soil solution at acidic pH values. Very few plants can grow well in strong acid soils. Soil acidity below pH value 5.5 is generally injurious to plants. Plant roots are badly affected if the pH value exceeds limits of tolerance for particular crops. High degree of soil acidity (pH 5.0 to 6.5) decreases the availability of plant nutrients particularly phosphorus, calcium, magnesium, molybdenum, iron, manganese, potassium sulphur nitrogen, boron, copper and zinc. It also affects adversely the important microbiological processes, such as nitrogen fixation by Azotobacter, Clostridium and nodule inhabiting bacteria (Rhizobia) of leguminous plants

Introduction Acid sulphate soils are formed when pyrite within a soil layer is oxidised, generating sulphuric acid. The oxidation of pyrite often results in yellow mottles of jarosite. The pH levels in greatly affected areas are often less than 4.0, and the associated environmental impacts include fish kills, retarded growth of crops and changes in water chemistry. Acid soils are distributed in tropical and subtropical regions, constituting approximately 30% of the ice-free land in the world, which is 50% of the world’s arable land. In China and India, 212 Mha or 12% of the agricultural land is classified as acidic. In India, about 28% of the total geographical area is affected by acidity of different degrees. Acid sulphate soils (ASSs) are a group of these soils having high soil acidity and other soil function limitations. These soils were termed as Kattecleigrondon or Kattakali by the Dutch farmers in the seventeenth century meaning ‘Cat Clays’ in English for soils of some reclaimed areas that became gradually highly acidic and developed prominent yellowish mottles and crusts composed of jarosite and related sulphates; in northern Germany, similar clays were called Maibolt. Occurrence They occur in many regions of the world, mostly along coastal areas where the land is inundated by sea water. Countries having extensive area of acid sulphate soils are:

Introduction The word “calcareous” has been commonly used as the generic description of all materials containing calcium carbonates greater than 10%. In the context of agricultural problem soils, calcareous soils are soils in which a high amount of calcium carbonate dominates the problems related to agricultural land use. They are characterized by the presence of calcium carbonate in the parent material and by a calcic horizon, a layer of secondary accumulation of carbonates (usually Ca or Mg) in excess of 15% calcium carbonate equivalent and at least 5% more carbonate than an underlying layer. Calcareous soils are common in the arid areas of the earth (FAO, 2016) occupying >30% of the earth’s surface. In the world Reference Base (WRB) soil classification system calcareous soils may mainly occur in the Reference soil group of calcisols. Formation / genesis of calcareous soils The soil are formed largely by the weathering of calcareous rocks and fossil shell beds like varieties of chalk, marl , lime stone and frequently a large amount of phosphates. Soils also can become calcareous through long term irrigation with water contains small amounts of dissolved CaCO3 that can accumulate with time. The secondary CaCO3 are formed under arid and semi-arid climatic conditions, when the carbonate concentration in the soil solution remains High Accumulation starts in the fine and medium sized pores at the surface of contact between the soil particles. This accumulation may be rather concentrated in a narrow zone of the solum or more dispersed depending upon the quantity and frequency of rainfall, topography, soil texture and vegetation. In high rainfall area i.e. in highly weathered soils, CaCO3 is dispersed from the surface horizons. While in arid and semi-arid regions due to low rainfall and limited leaching carbonates may be present in relatively high amounts. In medium deep and deep black clay soils carbonates are generally accumulated in subsurface horizons. However in some eroded shallow black soils they may be exposed right at the surface of soils. In some soils CaCO3 deposits are concentrated into layers that may be very hard and impermeable to water also

Introduction Waterlogging refers to the accumulation of excessive water in the root zone, leading to anaerobic conditions. This surplus water hampers the exchange of gases with the atmosphere, and biological processes deplete the oxygen supply in both soil and water, resulting in anaerobiosis, anoxia, or oxygen deficiency. In India, approximately 11.6 million hectares, constituting 8.3% of its net sown area, are affected by waterlogging (Planning Commission, 2011). According to Brundtland and Khalid (1987), available estimates indicate an annual global loss of 1.5 million hectares of irrigated land due to salinity and waterlogging. Regrettably, data regarding the occurrence and extent of these issues are inconsistent and incomplete. More recent estimates, provided by Datta and Joshi (1992), range from 5.5 million to 13 million hectares. After conducting a comprehensive global survey, it has been determined that submerged and waterlogged soils cover approximately 5 to 7% of the Earth’s land surface. The total area of waterlogged soil worldwide is estimated to be around 700 to 1000 million hectares. Tropical swamps, rice fields, and floodplains collectively represent nearly 14%, 12%, and 10% of the total waterlogged area, respectively. In India, Odisha, West Bengal, Bihar, and Uttar Pradesh have the highest concentration of waterlogged soil, with an estimated total area of one million hectares. The eastern region bears a significant portion of this burden, with over 20% of the affected land suffering from surface waterlogging, which severely diminishes productivity. Waterlogging is characterized by the soil becoming unproductive and infertile due to excess moisture, creating anaerobic conditions known as waterlogged soils. Waterlogged soil presents a significant challenge to agricultural productivity and soil health, characterized by excessive water saturation that restricts oxygen availability to plant roots. In this chapter, we delve into the multifaceted aspects of waterlogged soil, exploring its causes, defining characteristics, and far-reaching consequences. The serves as a comprehensive overview, underscoring the detrimental impact of waterlogging on agriculture, ecosystems, and human well-being. It identifies key factors contributing to

Introduction Soil crusts are surface alterations in the topsoil resulting from natural processes, such as the impact of raindrops followed by drying. These crusts manifest as thin, hardened layers on the soil surface, particularly common in arid and semi-arid regions. Their thickness typically varies from less than 1 mm to 5 cm (Evans and Boul, 1968). Once dry, these layers become denser, harder, and more brittle than the underlying soil, reducing both the number and size of pores and reorganizing the soil’s pore structure. In temperate regions, surface crusts primarily form on unstable loamy soils, particularly in areas under cultivation. In tropical regions, soil crusting affects a broader range of soils and poses a significant problem not only in arid zones but across various climatic conditions. In humid areas, intensive farming exposes the soil surface to high-energy rainfall for extended periods, accelerating the degradation of soil organic matter. As a result, bare soil areas expand, and biomass production declines. From an agronomic perspective, the most critical drawbacks of soil crusting are its negative effects on seedling emergence and water infiltration. Seedling emergence is particularly affected for crops with small seeds or when the timing of emergence is crucial due to climate or market demands. In some instances, costly replanting becomes necessary. The reduction in water infiltration caused by crusted soils creates significant challenges for irrigation, especially in areas where water scarcity limits large-scale use, forcing farmers to adopt more efficient water management strategies. Reduced water infiltration also leads to increased surface runoff, contributing to soil erosion and environmental risks, such as the pollution of surface waters due to nutrient loss. Additionally, restricted gas exchange between the soil and atmosphere further contributes to lower crop yields. Epstein and Grant (1973) observed that soil erodibility is closely linked to the rate and extent of crust formation, with soil loss peaking within the first 10 minutes of rainfall before stabilizing. It is well established that during crustforming rain events, water infiltration declines over time, leading to an increase in runoff volume. This increase in runoff, combined with the intensified energy

Introduction Soil, the outermost layer of the Earth’s crust, plays a vital role in supporting plant life. It consists of a mixture of mineral and organic materials, with its depth varying from negligible to several meters across different regions. Subjected to continuous atmospheric influences, soil experiences erosion, primarily driven by the movement of wind and water. Erosion, originating from the Latin word “erodere,” meaning “to eat away” or “to excavate,” involves the detachment, transportation, and deposition of soil particles. The erosion process encompasses two main phases: the detachment of individual soil particles from the soil mass and their subsequent transportation by various agents such as water, wind, ice, or gravity, followed by eventual deposition. Finer soil particles are more susceptible to erosion compared to coarser ones, leading to the formation of sediment, the ultimate product of soil erosion. Sediment, which refers to fragmented material transported or deposited by natural agents, illustrates the sedimentation process, reflecting the sequence of the sediment cycle. Detachment involves the dislodgment of soil particles from the soil mass by erosive agents such as impacting raindrops and runoff water. Transportation entails the entrainment and movement of these detached soil particles (sediment) from their original location, often through stream systems, towards eventual deposition sites, which may include the base of slopes, reservoirs, or floodplains. Soil erosion presents a significant threat to human well-being by diminishing the productivity of agricultural land through the removal and washing away of essential plant nutrients and organic matter. The widespread distribution of sediment load globally underscores the pervasive impact of erosion on natural landscapes and ecosystems.

Introduction Water is one of the most vital natural resources for sustaining life on Earth. However, its availability is not uniform across the planet, and the growing demand for freshwater in the face of climate change, population growth, and industrial development has raised serious concerns about the future of water resources. In 2024, the global water landscape presents both challenges and opportunities, shaped by shifting environmental patterns, technological advances, and policy responses to water scarcity. Water resources refer to the natural sources of water that can be utilized for various purposes, including water supply. Approximately 97% of the Earth’s water is saline, found primarily in oceans, while only about 2.5% is fresh water, but only a small portion of this is accessible. The majority of freshwater is locked in glaciers, ice caps, and deep underground aquifers. Less than 1% of Earth’s freshwater are readily available in rivers, lakes, and accessible groundwater for human use. Of this small fraction, nearly two-thirds is locked in glaciers and polar ice caps. The remaining unfrozen fresh water exists predominantly as groundwater, with only a small percentage available as surface water in rivers, lakes, and atmospheric moisture. The primary natural sources of freshwater include surface water, underflow in riverbeds, groundwater, and frozen water in glaciers. In addition to these, artificial sources such as treated wastewater (reclaimed water) and desalinated seawater are increasingly being used to supplement the global freshwater supply, particularly in regions facing water scarcity. As agriculture accounts for approximately 70% of global freshwater withdrawals, the management and quality of irrigation water are vital for sustaining food production and maintaining the health of ecosystems. Water is essential not only for basic plant functions, such as photosynthesis and nutrient absorption, but also for controlling temperature and supporting soil structure. In regions where rainfall is insufficient or irregular, irrigation provides a reliable source of water to meet the needs of crops throughout their growth cycle.

Introduction Soil is considered as a thin layered living entity over the earth’s surface, poses a profound implication on the solidity of ecosystems. It act as a transient nutrient sink for the plants and plays a crucial role in the crux of biogeochemical cycling of Earth’s elements which is being carried out by distinct microbial assemblages present in the soil profile. Soil is the most diverse niche for the microbial communities in which large proportion of taxa exists at a very low correlative abundance. Despite the extensive importance of this entity it has been snubbed lately with the various undesirable activities done by human kind. Therefore, the scientific understanding of soil origin is critical. Scientifically speaking, formation of one inch of soil almost took 15 years if the parent materials are soft whereas hard parent material might takes hundreds of year for its development. Soil horizon involves the arrangement of mature soil in a series of zones. Each horizon encompasses the distinct texture and composition that varies with different kinds of soils. Soil profile is the cross sectional view of the horizons in a soil. The O horizon is the topmost layer of soil, mainly consists of partially decomposed leaves, animal wastes, fungi and other organic materials. A horizon is looser than other deeper layers of soil, mainly dark in colour and considered as the uppermost layer of the soil consisting of partially decomposed organic matter known as humus. Generally, in the upper layers of soil the roots of most plants exist. As long as these layers are supported by vegetation, it acts as a storehouse of water which gets released in a trickle throughout the year. Plant roots grow in the soil and absorb nutrients and water which are required during the process of photosynthesis that helps in the growth and development of plants. Soil contains essential nutrients which are being adsorbs by the plants and is beneficial to all living organisms such as herbivores and omnivores depends on plants for their food, then these being eaten up by carnivores and omnivores in the food web, so nutrients that are absorbed from the soil is reached to all strata of living entity. Soil is a niche for different organisms as its top layers harbors a large population of bacteria, fungi, earthworms and many other small insects that

Introduction Water is chemical substance which important for all living organism to survive on this planet. Water is necessary for all cell of the living organism’s body to performance any normal work. Water covers 71% of the Earth’s surface, most like in oceans and other more water bodies, with 1.6% of water below ground in aquifers and 0.001% in the air as vapors, clouds and precipitation. Some observation have estimated that by 2025 more than half of the world population will be facing water-based vulnerability, a situation which has been called a ‘water crisis’ by the United Nations. A recent report suggests that by 2030, in some developing regions of the world, water desire will be exceed supply by 50%. The total volume of water 1,385 million Km3 on the planet earth, 96.5% is salt water (oceans and seas), the fresh water is mostly ice (24 million Km3). The fresh water available as annual stream flow is 46,768 Km3, that is 0.00034% of the total global water. If there is no intake of water into the body, death can ensue in 7-10 days. Water is also essential to man for maintaining personal hygienic and freedom from disease. Today there are many cities worldwide facing actual shortage of water and nearly 40 percent of the world’s food supply is grown under irrigation and a wide variety of industrial processes depends on water. Water is the most vital element among the natural resources, and is critical for the survival of all living any organisms including human, food production, and economic development. The environment, economic growth and developments are highly affected by water is regional and seasonal availability and the quality of surface and groundwater. The quality of water is affected by any human activities and is declining due to the rise of urbanization, population growth, industrial production, climate change and other factors. The resulting water pollution is a serious surrounding to the well-being of both the Earth and its population. The pressures is increasing population, growth of industries, urbanization, energy intensive life style, loss of forest cover, lack of environmental awareness, lack of implements of environmental rule, regulations and environment improvement plans, untreated effluent discharge from industries and municipalities, use of non

Any undesirable change in physical, chemical and biological properties of air is called air pollution. Air pollution interferes with wellbeing of living livelihood. Various human made and anthropogenic sources which deteriorate the air quality are called air pollutant. Some of the common air pollutant are dust, smoke, smog, fog, aerosol, SO2, CO2, O3 and NOx etc. Sources of Air Pollution The sources of air pollution are classified into two categories: 1. Natural source 2. Man-made source 1. Natural sources • Ash from burning volcanoes, dust from storm, forest fires • Pollen grains from flowers in air are natural sources of pollution 2. Anthropogenic (man-made) sources They are population explosion, deforestation, urbanization and industrialization whose effect can be explained as fallow: a) Power stations using coal or crude oil release CO2 in air b) Also furnaces using coal, cattle dung cakes, firewood, kerosene, etc. c) Steam engines used in railways, steamers, motor vehicles, etc. give out CO2. d) So do Motors and internal combustion engines which run on petrol, diesel and kerosene. etc. e) Vegetable oils, kerosene, and coal as household fuels f) Sewers and domestic drains emanating foul gases g) Pesticide residues in air h) Carbon monoxide and Nicotine from smoking i) Thermal power plants pollute air by emitted sulphur dioxide and fly ash j) Fertilizers and pesticides

Introduction Land is one of the most valuable natural resources on Earth. However, its significance varies across professions. Engineers view land as a foundation for constructing roads, buildings, and flyovers, whereas agriculturists consider it a medium for cultivating crops. For business professionals, land represents a space for establishing offices and industries. Although “land” and “soil” are sometimes used interchangeably, they are distinct. Land is typically regarded as a two-dimensional surface, while soil is three-dimensional, extending in depth. Another key difference is that land refers to any portion of the Earth’s surface, whereas soil consists of weathered rock materials enriched with essential nutrients, making it capable of supporting plant growth. The utilization of land should be aligned with its potential and limitations. Being a finite resource, land use is not solely determined by human needs but also by its capability. Over the past two decades, land degradation has become a growing concern globally, particularly in India. Land serves multiple purposes, primarily supporting agriculture, pastures, and forestry. A standard soil survey map illustrates the various types of soil that are important and their distribution in relation to other landscape features. These maps are designed to cater to users with diverse needs and, therefore, contain detailed information to highlight essential soil distinctions. For a soil map to be useful, the information it presents must be clearly explained to the user. These explanations are referred to as interpretations. Soil maps can be understood in two ways: (1) by examining the individual soil types showed on the map and (2) by grouping soils that exhibit similar responses to management and treatment. Since there are numerous types of soil, there are also many specific soil interpretations. These interpretations provide users with all the relevant information that a soil map can offer. However, many users require more generalized information than that of individual soil-mapping units. To address this, soils are classified in different ways based on the specific needs of the map users. The composition of these soil groups and the allowable variation

Introduction Accurate and detailed information on the geographical location, aerial extent, and spatial distribution of wastelands is crucial for their efficient management and sustainable rehabilitation. Among modern resource assessment tools, Remote Sensing (RS) and Geographical Information Systems (GIS) have emerged as powerful technologies for detecting, evaluating, mapping, and monitoring degraded lands. Space-borne multispectral imagery, with its ability to provide large-scale, repetitive coverage, has proven particularly effective in identifying salt-affected soils and waterlogged areas in a timely and cost-efficient manner. In visual interpretation of satellite data, regions with high soil moisture and surface waterlogging appear as dark grey to black, indicating areas prone to water stagnation. To analyze the spatial dynamics of wastelands and assess the effectiveness of high-resolution satellite imagery, IRS P6 satellite data (23.5 m resolution) alongside topographical maps (1:50,000 scale) are commonly used. Given the dynamic nature of wastelands, multi-temporal satellite data is essential for precise delineation. These images must be geo-referenced within a unified coordinate system for consistency. The Planning Commission of India has endorsed GIS as an indispensable tool for land-use planning and wasteland development, facilitating treatment area identification, landuse trade-off analysis, and impact assessment simulations. Recognizing the importance of wasteland management in national development, the Ministry of Environment and Forests (MoEF) initiated a GIS-based wasteland mapping project in 1991, building upon earlier efforts by the Department of Science (1986) under the National Wasteland Identification Project, which mapped 147 districts at a 1:50,000 scale. A Task Force was established to develop a standardized classification system, later approved by the Planning Commission, categorizing wastelands into:

Introduction Agroforestry, social forestry, community forestry, village forestry, and farm forestry are all practices that involve tree cultivation primarily outside designated forest reserves. Agroforestry, in particular, is a land-use approach that integrates trees with agricultural crops, shrubs, pastures, or livestock. This combination of trees and shrubs within land management systems can be structured in a spatial arrangement or occur in a sequential manner over time. The term ‘woody perennials’ is sometimes used to describe these trees and shrubs, referring to all long-lived plants that persist for more than a year, including bamboos and palms. In agroforestry systems, trees may not always be deliberately planted; natural regeneration may be encouraged by protecting emerging seedlings, or mature trees may be intentionally retained in fields and pastures. These woody perennials are often categorized as “multipurpose trees” (MPTs) or “multipurpose trees and shrubs” (MPTS) due to their diverse uses. While most trees can be considered multipurpose, this distinction highlights the varied benefits trees offer in agroforestry systems, as opposed to singlepurpose timber plantations focused solely on wood production. Conversely, tree cultivation in designated forest areas is often directed toward industrial needs, commonly referred to as industrial forestry. The promotion of MPTs in agroforestry holds great promise for addressing land-use challenges and improving livelihoods by enhancing environmental sustainability and economic opportunities for local communities. Agroforestry research has now advanced to a stage where suitable tree-crop combinations, their management practices, and genetically improved planting materials can be recommended for specific conditions. Furthermore, continuous advancements in research by international and national agroforestry organizations are contributing to the benefit of farmers. The availability of information on multipurpose tree species (MPTs) for many species has facilitated the adoption of agroforestry as a viable land-use system. However, for certain MPTs, a lack of fundamental data on growth rates, breeding patterns, resilience to environmental stress,

Introduction Agroforestry systems have the potential to make use of marginal and degraded lands through the soil improving effects of trees. Underlying all aspects of the role of agro forestry in maintenance of soil fertility is the fundamental proposition that trees improve soils. It would be useful to have guidelines on which properties of a tree or shrub species make it desirable for the point of view of soil fertility. This would help in identifying naturally occurring species and selecting trees for systems which have soil improvement as a specific objective. Agroforestry is a sustainable land management system which increases the overall yield of the land, combines the production of crops (including tree crops) and forest plants and/or animals simultaneously or sequentially, on the same unit of land and applies management practices that are compatible with the cultural practices of the local population. Nitrogen fixation and a high biomass production have been widely recognized as desirable. However, many properties are specific to particular objectives of systems in which the trees are used. Even species that are shunned for their competitive effects may have a role in certain designs. An example is the way in which Eucalyptus species with a high water uptake, which adversely affects yields in adjacent crops, have been employed to lower the water table and so reduce salinization The agroforestry systems comprises Agrisilivicultural systems (improved fallow species in shifting agriculture (jhum), hedgerow intercropping (alley cropping), multispecies tree gardens, multipurpose trees/shrubs on farmlands, plantation and other crops, shade trees for commercial plantation crops, soil conservation hedges etc.), Agrisilvipastoral systems (tree- livestock-crop mix ground, home garden, woody hedgerows for browse, green manure, soil conservation etc., integrated production of crops, animals ,fuelwood, poles, etc.), Silvipostoral systems (multipurpose fodder trees on or around farmlands,