eChapters

ABSTRACT

Satellite-based hyperspectral imaging became areality in November 2000 with the successful launch and operation of the Hyperion system on board the EO-1 platform. Hyperion is a push broom imager with 220 spectral bands in the 400-2500 nm wavelength range, a 30 meter pixel size and a 7.5 km swath. Prelaunch characterization of Hyperion measured low signal to noise (SNR<40:1) for the geologically significant shortwave infrared (SWIR) wavelength region (2000- 2500 nm). The impact of this low SNR on Hyperion's capacity to resolve spectral detail is studied for the Musiri and Tattayyangarpettai regions of part of Namakkal and Tiruchirapalli districts of Tamil Nadu state, India which comprises a diverse range of minerals with narrow, diagnostic absorption bands in the SWIR. Following radiative transfer correction of the Hyperion radiance at sensor data to surface radiance (apparent reflectance), diagnostic spectral signatures were clearly apparent including: green vegetation; talc; dolomite; crystalline limestone, chlorite; white mica and sericite. Though the derived surface composition maps generated from these image endmembers were noisy (both random and column), the spatially coherent and correlated well with the known geology. The interpreted and processed mineral map is given below. In addition, the Hyperion data were used to measure and map spectral shifts of <10 nm in the SWIR related to white mica chemical variations.

ABSTRACT

Greenseeker is a handheld computer mounted sensor for observing normalized difference vegetation Index [NDVI= (NIR “R)/(NIR+R)], which may be used to estimate site specific amount of fertilizer nitrogen depending up on the crop condition. The sensor can be used for yield estimation and developing remote sensing based growth models. It is an active sensor with a built in light source for illuminating the target and records reflected light from vegetation at wavelength of 670 nm (red region) and 780 nm (near infrared region) of electromagnetic spectrum. The swath covered by the Sensor is 0.75 m when sensor is placed about 1.0 m above crop canopy.

The sensor was used to record NDVI in wheat- sugarcane intercropping system wherein wheat was grown on raised beds of 1.04 m width with six rows of wheat and sugarcane in furrows at row spacing of 1.38 m. The wheat variety PBW 343 was sown with nitrogen levels @ 0, 30, 60, 90, 120, 150, 180 and 210 kg N ha^-1 (all basal) and sugarcane variety CoSe 92423 was planted in furrows on 7^th November, 2006 in a medium textured loam soil.

The NDVI was recorded in wheat at 17, 41, 59, 73, 88, 113 and 129 DAS using Greenseeker and Spectroradiometer (UNISPEC ^TM of PP system, USA) simulating normal satellite bands i.e.

NIR: 770-860 nm, Red: 620-680 nm, Green: 520-580 nm. The maximum NDVI (recorded at 88 DAS) was used to develop INSEY “ yield relationship in wheat. The NDVI recorded by Greenseeker was integrated with NDVI recorded by Spectroradiometer.

The Greenseeker was also used to monitor crop growth in sugarcane. The NDVI was correlated with shoot population, plant height, LAI and total biomass during formative and crop elongation phase of sugarcane till end of November 2007. Highly significant (at 1%) correlation was observed between GS- NDVI and shoot population till mid August and LAI in sugarcane for entire crop cycle. An exponential model (R² = 0.9017) was developed to estimate LAI of sugarcane from NDVI. The NDVI was significantly (at 5 %) was correlated with plant height till mid August. However, the correlation between total crop biomass in sugarcane and NDVI remained non-significant.

ABSTRACT

In the present paper, study of spectral reflectance measurements has been carried out for different type of snow and other ambient objects in snowbound areas of Indian Himalaya using Spectroradiometer (350-2500nm). The observations suggest that there are significant changes in the spectral radiances and reflectance values of snow and other ambient objects, which can be discriminated using satellite multi-spectral bands, however for characterizing the snow using satellite sensor, spectral bands having maximum radiances values should be greater than snow radiances and suitable spectral bandwidth are to be identified. The detail analysis of field collected reflectance suggest that, due to aging and grain size variation in snow, the maximum variations in reflectance was observed in the NIR region i.e. around 1040-1050nm. For contamination and snow depth, the maximum variation was observed in the visible region i.e. around 470nm and 590nm respectively. For the moisture changes, the maximum variations observed around 980 and 1160nm. The study also suggests, normalized difference snow index (NDSI) increases with the increase of aging, grain size and moisture content. This study can be helpful in selection of suitable spectral bands for snow cover applications using satellite

remote sensing and developing the algorithms for seasonal snow cover characteristics using multi-spectral and hyper-spectral data.

ABSTRACT

The Mumbai region of Maharashtra has been witnessing very rapid urbanization development in terms of industrial, commercial and residential establishments. This has resulted in reclamation of tidal flats and estuarine regions. The ‘marine clay', characteristic of this environment has high swelling potential and consequently affects the performance of the structures. This will have a serious negative impact on the urbanization expansion. In this study, an attempt is made to map the spatial distribution of these expansive clays using the state of art Hyperion data. Reflectance spectra of representative samples collected from the field is used to map marine clays using Spectral Angle Mapper (SAM) technique. Laboratory analyses of these foundation soils (reflectance spectroscopy, mineralogy and Atterberg limits) indicate that they have significant amount of montmorrilonite and has good swelling potential (A_C>1.4). The derived expansive clay abundance map will be of use while planning appropriate remedial measure and future development.

Key Words : Swelling clay, Spectral characters, Geotechnical properties

ABSTRACT

A study was conducted to compare inter-sensor variability by computing vegetation indices, NDVI & SR. The two sensors compared were Hyperion and ALI (Advanced Land Imager) present on EO-1 satellite. Hyperion is a hyperspectral sensor having a spectral range of 400-2500nm with 10nm bandwidth. ALI is a multispectral sensor with 10 bands of 100nm bandwidth. Hyperion and ALI data were acquired at the same time for two different seasons, dry (April) and wet (October) seasons over Shoolpaneshwar Wildlife Sanctuary, Gujarat, India. Vegetation indices such as SR “ Simple Ratio and NDVI -Normalized Differential Vegetation Index were performed. Seasonal variations were observed in both the data sets. For SR index, Hyperion performed well using October month data. In comparison with ALI, Hyperion showed high NDVI for both deciduous and evergreen species using October month data. The highest NDVI value is assumed to represent the maximum vegetation “greenness” during that period. Results clearly indicated the superiority of Hyperion in vegetation analysis using NDVI & SR indices.

Keywords : Hyperion data (EO-1), ALI (Advance Land Imager),Shoolpaneshwar Wildlife Sanctuary, NDVI, Simple Ratio (SR)

ABSTRACT

Spectral signatures are the specific combination of reflected and absorbed electromagnetic radiation at varying wavelengths which can uniquely identify an object. The “Spectral signature” of an object is a function of 1) incidental EM wavelength and material interaction with that section of the electromagnetic spectrum. The measurements can be made with various instruments, including a task specific spectrometer, although the most common method is separation of the Red, Green, Blue and Near Infrared portion of the EM spectrum as acquired by digital cameras. The spectral signatures serve as diagnostic tools in understanding the composition and structure of the materials. The present paper highlights the usefulness of the spectral signatures in rock and mineral discrimination and mineral exploration and stresses the need for creation of a spectral data base in India for various applications.

1. INTRODUCTION

Objects at the Earth's surface emit and reflect many wavelengths of radiation. In principle, each object has a unique spectral signature, which could be used for identification much like a finger print. Remotely sensed spectral signatures could be utilized for recognizing and mapping for all kinds of features. This can be done to a limited extent with conventional multispectral scanners that operate in a few broad bands of visible and infrared energy. However, broad spectral bands often do not distinguish between similar features. To overcome this limitation, a more sophisticated approach toward spectral signatures has arisen during the past few years. This approach is called image spectroscopy or hyperspectral analysis, which is based on scanning hundreds of closely spaced and very narrow spectral bands. With this technique, it is possible to create continuous spectral response curves, which may be used to identify many objects positively.

ABSTRACT

Mineral composition and their distribution on planetary surfaces provides important clues to the evolutionary processes that the planetary bodies have undergone since their formation. For distant and inaccessible planets, remote sensing, either from Earth-based telescopes or from an orbiter around the planetary body, using reflectance spectroscopy over a wide range of the electromagnetic spectrum (UV-Visible-IR), can provide surface distribution of minerals. With advances in technology, a high-resolution hyperspectral imager onboard an orbiter has developed into a powerful tool for compositional mapping of planetary surfaces. Interpretation of the signals from these distant and relatively unknown destinations is a challenging task due to scarcity of available ground truth. Here, we describe the technique with its applicability to airless bodies, such as Moon, in the context of the Indian Moon mission, Chandrayaan-1, and, the intricacies involved in the data analyses.

Keywords : Reflectance spectroscopy, hyperspectral data, remote sensing, planets, moon

1. INTRODUCTION

The primary goal of planetary exploration is to understand the mechanism by which planetary objects (planets, dwarf planets, satellites and small solar system bodies) have evolved with time. The information gathered from the study of individual bodies is integrated to comprehend the development of our solar system. The present understanding envisages our solar system to have formed from the solar nebula, produced as a consequence of the collapse of a molecular cloud. While the central mass gravitated and formed the sun, the gas and dust surrounding it condensed to form grains and formed the proto-planetary disk. These grains, through a series of processes, finally aggregated to form of the various planetary bodies. Existing Astronomical, chemical and mineralogical evidences from studies of lunar samples, meteorites and, remote sensing observations suggest that the planetary bodies are heterogeneous and possess extreme compositional and morphological diversity. The internal energy of a planetary body, a function of its size, is responsible for the differences in the degree of differentiation a body has undergone leading to the variations in their surface composition. Large planets like the Earth and Venus are still evolving whereas the small asteroids have barely evolved after their formation and are considered primitive. The wide variety of planetary bodies in our solar system is therefore reminiscent of the various stages of evolution that our solar system went through. The degree of melting and cycling through episodes of differentiation determine the mineral inventory on a planetary body. Therefore, distribution and composition of various minerals can be used to understand various stages of chemical evolution of a planetary body. Mineral mapping of planetary surfaces is thus useful in understanding the petrogenetic history.

ABSTRACT

This paper reviews the various application of hyperspectral remote sensing data carried out by the scientists of India emphasizing its advantages.

1. INTRODUCTION

The most significant recent breakthrough in remote sensing has been the development of hyperspectral sensors. The ‘Hyper’ in hyperspectral means ‘too many’ and refers to the large number of measured wavelength bands. Hyperspectral images are spectrally over determined, which means that they provide ample spectral information to identify and distinguish spectrally unique materials. Hyperspectral imagery provides the potential for more accurate and detailed information, extraction than is possible with any other type of conventional remotely sensed data.

Imaging spectroscopy (Goetz et al., 1985) in hyperspectral imaging is concerned with the measurement, analysis, and interpretation of spectra acquired from a given scene (or specific object) at a short, medium or long distance by an airborne or satellite sensor. The concept of imaging spectroscopy originated in the 1980's, when A. F. H. Goetz and his colleagues at NASA's Jet Propulsion Laboratory began a revolution in remote sensing by developing new instruments such as the Airborne Imaging Spectrometer (AIS), then called AVIRIS, for Airborne Visible Infra-Red Imaging Spectrometer (Green et al., 1998). This system is now able to cover the wavelength region from 0.4 to 2.5 μm using more than two hundred spectral channels, at nominal spectral resolution of 10 nm. The special characteristics of hyperspectral datasets pose different processing problems, which must be necessarily tackled under specific mathematical formalisms, such as classification and segmentation (Jia et al., 1999, Green, R 1998) and spectral mixture analysis (Adams et al., 1986; Smith et al., 1990a, b).

ABSTRACT

Over the last decade, hyperspectral remote sensing has become a powerful analysis tool for applications in environment and ecology, aquaculture, forestry, agriculture, and geoscience. A hyperspectral imagers advantage over broadband sensors, such as Landsat Thematic Mapper (TM) and the SPOT Haute Resolution Visible (HRV) sensor series, is its ability to detect molecular absorption and particle scattering signatures of constituents. The finer spectral resolution of a hyperspectral imager allows detection of surface materials and their abundances, as well as inferences of biological and chemical processes. This review highlights the vast extent to which hyperspectral technology and their application with special reference to ocean have been discussed.

ABSTRACT

Remote sensing has undergone tremendous development in past decades. Hyperspectral imaging refers to the imaging of a scene over a large number of discrete, narrow contiguous spectral bands in the visible through thermal infrared portion of the spectrum. Thus it is possible to construct a complete reflectance spectrum of every pixel in the scene.

Classification of hyperspectral image requires thorough understanding of surface material properties, sensor characteristics and atmospheric absorption spectra. The reflectance spectra of most materials on the Earth's surface contain diagnostic absorption features. Remote sensors, capable of acquiring complete reflectance spectra over large areas, offer a powerful tool to study of the Earth and the environment. Methods are being developed to extract information from remote sensing data using image-processing approaches. Specific absorption features of reflectance spectrum can be used to identify a number of important rock forming minerals, and have been used by geologists for geologic mapping and studies of volcanoes.

The present discussion includes an application of thermal characteristics of near- IR bands of Landsat TM to estimate the temperature of over and around the crater of Barren Island volcano in 1991. A method using dual band temperature characteristics related to radiant source of sub-pixel size was developed and utilized to prepare temperature contour map of the Island using unsaturated pixels of band 5 and 7.

ABSTRACT

Multispectral imagery has been used as the data source for natural resource mapping and land observational remote sensing from airborne and satellite systems since the early 1960s. Over the past two decades, advances in sensor technology have made it possible for the collection of several hundred spectral bands. This is commonly refe rred to as hyperspectral imagery. Thus it is possible to construct a complete reflectance spectrum of every pixel in the scene. This review highlights the hyperspectral remote sensing system development, hyper spectral data processing and difference between multispectral and hyperspectral data; spatial and spectral resolutions and focuses on the application of hyperspectral imagery in natural resource studies and, in particular the classification and mapping of land resources.

The transition from conventional to organic farming requires numerous changes. One of the biggest changes is in the mindset of the farmer. Conventional approaches often involve the use of quick-fix remedies that, unfortunately, rarely address the cause of the problem. Transitioning farmers generally spend too much time worrying about replacing synthetic input with allowable organic product instead of considering management practices based on preventative strategies. Here are a few steps new entrants should follow when making the transition to organic farming:

20.1. Understand the Basics of Organic Agriculture and the Organic Farming Standards

Since organic production systems are knowledge based, new entrants and transitional producers must become familiar with sound and sustainable agricultural practices. Transitional producers should be prepared to read appropriate information, conduct their own trials and participate in formal and informal training events. As mentioned, switching from conventional to organic farming is more than substituting synthetic materials to organic allowed materials. Organic farming is a holistic system that relies on sound practices focused on preventative strategies. Since there are often few organic remedies available to organic producers for certain problems, prevention is the key element in organic production.

In food production remarkable progress has been made in the last fifty years in agricultural production and self – sufficiency (Food security) has been reached. Yet nutritional security seems to be a distant goal. With depleting natural resources and increasing threat to the environment, sustainable crop production is attracting the attention of the scientists, farmers and administrators. Due to over exploitation of natural resources and indiscriminate use of agro chemicals, green revolution also brought in quite a lot of miseries which focus the urgent need to have EVERGREEN REVOLUTION that is sustainable, leading to food and nutritional security to the rural poor. At this juncture it will be more appropriate to practicing organic agriculrure through the integration of traditional wisdom and modern scientific knowledge in synergy with nature.

19.1. Eco-friendly Technologies for Rice Cultivation

A sound package of eco-friendly technologies to grow rice is being successfully adopted by a few progressive farmers in Puliangudi village in Tirunelveli district of Tamil Nadu. “The technologies work well with indigenous rice varieties such as Kitchili Samba. The cost of cultivation is substantially reduced and the organic rice fetches a premium price in the market,” says Mr. P. Gomathinayagam, a pioneer in organic farming in Puliangudi.

In India, there are two accreditation systems for authorizing Certification and Inspection agencies for organic certification. National Programme on organic Production (NPOP) promoted by Ministry of Commerce is the core programme which governs and defines the standards and implementing procedures. National Accreditation Body (NAB) is the apex decision making body. Certification and Inspection agencies accredited by NAB are authorized to undertake certification process. The NPOP notified under FTDR act and controlled by Agricultural Processed Foods Export Development Authority (APEDA) looks after the requirement of export while NPOP notified under APGMC act and controlled by Agriculture Marketing Advisor, Directorate of Marketing and Inspection looks after domestic certification. Currently 20 certification agencies have been authorized to undertake certification process.

National Programme on Organic Production

National Program on Organic Production (NPOP) was launched during 2001 under the Foreign Trade & Development Act (FTDR Act). The document provides information on standards for organic production, systems criteria, and procedures for accreditation of Inspection and Certification bodies, the national organic logo and the regulations governing its use.

Realizing that nematodes cannot be eliminated, and that we must live with them, the overall goal is to keep the population density as low as possible. The economic threshold is the density of nematodes where the losses incurred exceed the cost of nematode management. It is not advisable to depend on a single method to control nematodes. Efficient management requires judicious and careful integration of several which will result in reduction of nematode populations. Important components of non chemical methods of nematode management program are considered in this chapter.

17.1. Organic Amendments

Manure and fertilizer applications are essential part of growing any crop. Besides supplying required essential nutrients theyhelp in many ways directly or indirectly by suppressing harmful organisms including phytonematodes. The use of organic amendments against nematodes was demonstrated by Linford et al., in as early as 1938. FYM and cattle urine have found to reduce nematode population. Biogas plant waste slurry was found to be effective for nematode management. Compost of water hyacinth, oilcakes, cellulose amendments like sawdust, wheat straw, rice husk, rice hull ash, green manuring with legumes, green leaf incorporation are useful to keep nematode populations low. Non - edible oilcakes like those of neem, karanj, mahua, caster, cotton as well as edible oilcakes groundnut, mustard sesame, coconut have been recommended at 2 - 2.5 t/ha for reduction of root knot and other nematode population in soil. Miscellaneous substances like decaffeinated tea waste, rice hull ash, chicken manure, tannery and food and fruit processing waste, market and domestic organic refuse, dead vegetation and crop stalks, wood shaving, etc. have been recommended for root knot nematode management. Castor leaves (40g/kg) along with NPK at 75:25:37.5 kg/ha achieved reduction of M. javanica population on tomato.

Paddy is cultivated about 45 m ha in India, less than 1% is under organic cultivation.

16.1. Varieties

Good quality fine varieties like Ponni, Super ponni, insect and disease resistant varities must be selected for getting higher yield and returns.

16.2. Seeds

Organically produced seeds only must be used.

16.3. Seed Treatment

For 1 kg of seeds 20 g Azospirillum, Pseudomonas and 10 g Phospobacteria must be used with rice gruel.

Panchagavya spray @ 1% for treating the seeds.

15.1. IFS Components Tested for Wetlands

Area Allocation;

In 1 ha of land

75 % - Cropping

10 % - Fodder cultivation

3 % - Goat shed

12 % - Fish pond

Possible Integrations:

14.1. Water Source Identification

• In places where Ficus religiosa tree is found, underground water will be more.
• Underground water will be more in places where the neem tree with more knots is found.
• In places where termite hills are found, underground water will be more.
• Farmers are practicing traditional method of using neem stick, metals etc. for finding the water resource in underground for digging wells. While they are walking with this stick on hand it will be rottate automatically at the place where underground water is surplus.
• Some farmers are using the magnetic stones for identifying water sources. Magnet is tied with a thread and held like a pendulum while walking over the fields. The magnet will rotate automatically at the place where underground water is more and this is taken as the indication for digging wells.

13 1. Rishi Krishi

Drawn from Vedas, the Rishi Krishi method of natural farming has been mastered by farmers of Maharashtra and Madhya Pradesh. In this method, all on-farm sources of nutrients including composts, cattle dung manure, green leaf manure and crop biomass for mulching are exploited to their best potential with continuous soil enrichment through the use of Rishi Krishi formulation known as “Amritpani” and virgin soil. 15 kg of virgin rhizosperic soil collected from beneath of Banyan tree (Ficus bengalensis) is spread over one acre and the soil is enriched with 200 lit Amritpani.

It is prepared by mixing 250 g ghee into 10 kg of cow dung followed by 500 g honey and diluted with 200 lit of water. This formulation is utilized for seed treatment (beej sanskar), enrichment of soil (bhumi sanskar) and foliar spray on plants (padap sanskar). For soil treatment it needs to be applied through irrigation water as fertigation. The system has been demonstrated on a wide range of crops i.e. fruits, vegetables, cereals, pulses, oilseeds, sugarcane and cotton.

12.1. General Practices for Storage

• Lime juice is mixed with grains and then sun dried before storage to prevent insect pests (Farmers in Nigeria).
• Seeds are safely stored in earthern pots after mixing with the leaves of neem and Vitex negundo (Farmers in Gujarat, India).
• Drying seeds and grains of all the crops on the new moon day before storing to avoid pest attack.
• Store seed materials in earthen pots which are kept on the ‘Paran’ directly above the furnace in kitchen. The smoke acts as a repellent.
• Grains, trees etc. harvested on full moon day are raqre prone to storage pest attack.
• Mixing the dried leaves of neem with seeds while storing them.