Thursday, 17 December 2015

Detailed Landuse - Landcover Classification


Monday, 14 December 2015

Telengana (INDIA) Forest Statistics

Telangana State of Forest health of the notified Forests in the new state gives precise locations of the forest cover changes assessed using LISS III data of 2011 & 2012 seasons up to Compartment level.
It shows that forest cover has depleted to some extent inside the notified forests during the period. The changes have been communicated to field officers and almost all plots were visited, which gives high authenticity to the results. The following are the key results of this assessment:
Key Results:
1. The state has 502.35 Sq.Km of Very Dense forest, 9052.41 Sq.Km Moderately Dense Forest & 9209.91 Sq.Km Open forest in 2012 and corresponding figures in 2011 are 502.35 Sq. Km of VDF, 9063.02 Sq.Km MDF, 9235.86 Sq.Km Open forest.
2. There is a reduction of 10.61 Sq.Km in MDF and 25.94 Sq.Km in open forest. There is net loss of 36.55 Sq.Km during this period.
3. There is degeneration of forests from higher canopy density class to lower canopy density class in an extent of 36.55 Sq.Km.
4. 7.71 Sq.Km MDF, 25.66 Sq.Km OF and 16.51 Sq.Km scrub has been converted into Non-forests. Also 5.80 Sq. Km  into scrub forest. Of this, 26.02 Sq.Km of forest is lost due to fresh encroachments, 24.78 Sq.Km due to clearance of jungle growth for raising of plantations, 4.35 Sq. Km harvesting of matured.
As negative change in forest cover due to clearance of jungle growth for raising of plantations and harvesting of plantations is only a management intervention, the same is not considered as permanent loss of forest cover. Hence, the net loss of forest cover by encroachment during this period is 26.02 Sq.Km.
6. VSS areas account for 8.27 Sq. Km of encroachments.
7. Protected Areas account for 3.37 Sq. Km of encroachments.
8. Most negative change due to encroachments of 14.45 Sq.Km was found in Khammam Circle followed by Warangal Circle with 6.15 Sq.Km and FDPT Amarabad Circle showed the least negative change due to encroachments of 0.11 Sq.Km.
9. Encroachments were noticed in 23 Divisions of the state. The Divisions contributing most negative changes due to encroachments are: Warangal(South) (4.93 Sq.Km), Kothagudem (4.25 Sq.Km),
Paloncha (3.64 Sq.Km), Khammam (3.14  Sq.Km), Paloncha WLM (2.69 Sq.Km), Nizamabad (2.41 Sq.Km), KamaReddy (0.82 Sq. Km).
10. No changes were found in Medak WLM and Mahabubnagar Divisions.
11. Though there are lot of plantations for improving vegetation cover and growing stock, they are not discernible as to their growth in most cases. This is resulting in loss for forest cover. 

The technical committee formed by G.O Ms.No.57, EFS&T (For III) Department, dated 07-05-2011 on Geomatic activities has noted this with concern in its meeting held on 10-06-2013 advised to take up result oriented afforestation.

Telangana is the twelth largest state in India, geographical area wise; with an area of 112101 Km2. It is bounded by Maharastra, Chhattisgarh and Orissa in the north, Andhra Pradesh in the east and south and Karnataka & Maharastra in the west. The state was formed on 2nd June, 2014 by Government of India as 29th State. It has 26903.70 Km2 of notified forest land, which is 24.00% of the Geographical area.

The population of the state is 33.61million (2011 census) which is 2.77 % of country’s population.Nearly 61.33% of the population of the state is rural, which primarily depends on agriculture for livelihoods.Scheduled castes constitute about 15.43% and Scheduled tribes about 9.33% of the population.Hyderabad, Karim Nagar, Nizamabad, Khammam and Warangal are the principal towns in the state with over a million population. Traditionally, the state is divided into two regions called South Telangana Region, consisting of the 4 districts and North Telengana region consisting of 5 districts.

Prior to 1996, there was no mechanism to monitor the Forest cover changes in composite state of Andhra Pradesh. It used to rely on the data given by the Forest Survey of India, Dehradun throughits biennial ‘State of Forest Reports’. However, these reports, which were brought out since 1987, did not provide the statistical information on the forest cover inside the notified forest under the control of forest Department and outside, separately.
It presented a nation wide & state wise picture of the green cover, inclusive of the areas outside the notified forests. These provide data only upto the district level and no statistics of forest/tree cover were available below the district units. Therefore a necessity was felt for generating this data for the notified forest areas, which are under the control of Forest Department, upto the smallest unit of administration, i.e, Beat level and the management i.e, compartment level.
This could have been possible only with the setting up of Geomatics unit at the state level. This required procurement of satellite imagery, Hardware, Software, and technical trained manpower for which huge investment was essential. The opportunity came with the launch of WorldBank funded Andhra Pradesh Forestry Project in 1994. 

A consultancy for setting up and operationlization of a Geomatics center at Hyderabad was provided in the project and given to FAO, Rome. Dr K.D. Singh was the principal consultant for this consultancy. A small Geomatics Center was set up in a small room in the old Aranya Bhavan building with a PC (386 Processor) with 80MB harddisk and 1MB RAM.
The first software installed was the IDRISI package gifted by the FAO. In due course of time, other required hardware and software were added to the Geomatics Centre.

Initially, few Officers of the Department were sent for training in the Remote Sensing, GPS, Inventory and GIS at ITC, Netherlands, Finnish Forest Research Institute, Finland, IIRS, Dehradun and NRSC, Hyderabad. On successful completion of the training, these Officers started working in the Geomatics centre and started sensitizing the other Officers in the use of Remote Sensing, GIS and GPS. Gradually, the trainings were extended to the officers & staff of Department and also to the other members like VSSs.

The first thing required for the monitoring of forest cover changes upto Beat level was to create geo-spatial database both from Administrative as well as Management point of view. It was decided to create these    Geo-spatial database (Vector layers) on 1:250 K Scale. This work was outsourced by tender process in 1994 to “Remote Sensing Instruments” Hyderabad, for digitization of forest blocks, administrative boundaries, rivers, water bodies, villages, roads and forest cover density layers with attribute data.
These layers were generated by the end of 1995. Subsequently ERDAS software and PC Arc Info version 3.4.2 were procured. Subsequently about 250 basic and derived themes were generated on 1:50 K Scale. This data is being used in the monitoring of forest cover changes and several other applications in the department. The IT wing has been procuring all the latest hardware, software, data as and when required.
Now it is equipped with latest hardware like Blade Servers, High-end workstations, Firewall, PDAs, Multi frequency DGPS receivers and the sophisticated software like ArcGIS Server, Leica Photogrammetric Suite, ERDAS 2012, ArcGIS 2012, Skyline Globe and the Center has become State of the Art facility in IT & Geomatics. It has also developed webenabled modular based GIS-MIS integrated Telangana State Forest Management Information’s System (TGFMIS).

Spatial Distribution of Forest Map given below (Dark Green Areas are Forest Areas):


Monday, 7 December 2015

Sunday, 1 November 2015

Rajasthan - Barmer district Yield Forecast

Below picture shows yield forecast of Higher yielding areas, Medium yielding areas and low yielding areas of Bajra & Guar Crops of current Kharif season - 2015.

For Convenience of Spatial distribution of these crops, Sub-District boundaries have been overlaid.



Tuesday, 27 October 2015

Mustard Crop Profile - True Representation is NDVI


NDVI values showing along with dates and different crop stages.

Where as in Rice/Wheat there is no dip in NDVI. But in Mustard NDVI dip will occur because there was a flowering, the above graph is clearly depicting the same

Friday, 23 October 2015

Integrated Water Resource management - Using Remote Sensing Technology

Integrated Water Resource management

Water resources are sources of water that are useful or potentially useful to humans. Uses of water include agricultural, industrial, household, recreational and environmental activities. Virtually all of these human uses require fresh water. 97.5% of water on the Earth is salt water, leaving only 2.5% as fresh water of which over two thirds is frozen in glaciers and polar ice caps. The remaining unfrozen fresh water is mainly found as groundwater, with only a small fraction present above ground or in the air. Fresh water is a renewable resource, yet the world's supply of clean, fresh water is steadily decreasing. Water demand already exceeds supply in many parts of the world, and as world population continues to rise at an unprecedented rate, many more areas are expected to experience this imbalance in the near future. This will lead a severe water crisis. The framework for allocating water resources to water users (where such a framework exists) is known as water rights.

Sources of Water:

  1. Surface water:

Surface water is water in a river, lake or fresh water wetland. Surface water is naturally replenished by precipitation and naturally lost through discharge to the oceans, evaporation, and sub-surface seepage.

Although the only natural input to any surface water system is precipitation within its watershed, the total quantity of water in that system at any given time is also dependent on many other factors. These factors include storage capacity in lakes, wetlands and artificial reservoirs, the permeability of the soil beneath these storage bodies, the runoff characteristics of the land in the watershed, the timing of the precipitation and local evaporation rates. All of these factors also affect the proportions of water lost.

Human activities can have a large impact on these factors. Humans often increase storage capacity by constructing reservoirs and decrease it by draining wetlands. Humans often increase runoff quantities and velocities by paving areas and channelizing stream flow.

The total quantity of water available at any given time is an important consideration. Some human water users have an intermittent need for water. For example, many farms require large quantities of water in the spring, and no water at all in the winter. To supply such a farm with water, a surface water system may require a large storage capacity to collect water throughout the year and release it in a short period of time. Other users have a continuous need for water, such as a power plant that requires water for cooling. To supply such a power plant with water, a surface water system only needs enough storage capacity to fill in when average stream flow is below the power plant's need.

Nevertheless, over the long term the average rate of precipitation within a watershed is the upper bound for average consumption of natural surface water from that watershed.

Natural surface water can be augmented by importing surface water from another watershed through a canal or pipeline. It can also be artificially augmented from any of the other sources listed here; however in practice the quantities are negligible. Humans can also cause surface water to be "lost" (i.e. become unusable) through pollution.

  1. Sub-surface water:

Sub-Surface water travel time Sub-surface water, or groundwater, is fresh water located in the pore space of soil and rocks. It is also water that is flowing within aquifers below the water table. Sometimes it is useful to make a distinction between sub-surface water that is closely associated with surface water and deep sub-surface water in an aquifer (sometimes called "fossil water").

Sub-surface water can be thought of in the same terms as surface water: inputs, outputs and storage. The critical difference is that due to its slow rate of turnover, sub-surface water storage is generally much larger compared to inputs than it is for surface water. This difference makes it easy for humans to use sub-surface water unsustainably for a long time without severe consequences. Nevertheless, over the long term the average rate of seepage above a sub-surface water source is the upper bound for average consumption of water from that source.

The natural input to sub-surface water is seepage from surface water. The natural outputs from sub-surface water are springs and seepage to the oceans.

If the surface water source is also subject to substantial evaporation, a sub-surface water source may become saline. This situation can occur naturally under endorheic bodies of water, or artificially under irrigated farmland. In coastal areas, human use of a sub-surface water source may cause the direction of seepage to ocean to reverse which can also cause soil salinization. Humans can also cause sub-surface water to be "lost" (i.e. become unusable) through pollution. Humans can increase the input to a sub-surface water source by building reservoirs or detention ponds.

Water in the ground is in sections called aquifers. Rain rolls down and comes into these. Normally an aquifer is near the equilibrium in its water content. The water content of an aquifer normally depends on the grain sizes. This means that the rate of extraction may be limited by poor permeability.

Water crisis: Water crisis is a term that refers to the status of the world’s water resources relative to human demand. The term has been applied to the worldwide water situation by the United Nations and other world organizations. The major aspects of the water crisis are overall scarcity of usable water and water pollution. 1.6 billion people have gained access to a safe water source since 1990. The proportion of people in developing countries with access to safe water is calculated to have improved from 30 percent in 1970 to 71 percent in 1990, 79 percent in 2000 and 84 percent in 2004, parallel with rising population. This trend is projected to continue.

The Earth has a finite supply of fresh water, stored in aquifers, surface waters and the atmosphere. Sometimes oceans are mistaken for available water, but the amount of energy needed to convert saline water to potable water is prohibitive today, explaining why only a very small fraction of the world's water supply derives from desalination.

There are several principal manifestations of the water crisis:
  • Inadequate access to safe drinking water for about 1.1 billion people.
  • Groundwater overdrafting leading to diminished agricultural yields.
  • Overuse and pollution of water resources harming biodiversity.
  • Regional conflicts over scarce water resources sometimes resulting in warfare.

Integrated water resource management:
Integrated Water Resources Management (IWRM)has been defined by the Technical Committee of the Global Water Partnership (GWP) as "a process which promotes the coordinated development and management of water, land and related resources, in order to maximize the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems." Operationally, IWRM approaches involve applying knowledge from various disciplines as well as the insights from diverse stakeholders to devise and implement efficient, equitable and sustainable solutions to water and development problems. As such, IWRM is a comprehensive, participatory planning and implementation tool for managing and developing water resources in a way that balances social and economic needs, and that ensures the protection of ecosystems for future generations. Water’s many different uses—for agriculture, for healthy ecosystems, for people and livelihoods—demands coordinated action. An IWRM approach is an open, flexible process, bringing together decision-makers across the various sectors that impact water resources, and bringing all stakeholders to the table to set policy and make sound, balanced decisions in response to specific water challenges faced.

It has been agreed to consider water as an 'economic commodity' in order to emphasize on its scarcity in the Dublin Principles:

Fresh water is a finite and vulnerable resource, essential to sustain life, development and the environment.

Water development and management should be based on a participatory approach, involving users, planners and policy makers at all levels.

Why integrated water resource management:
  • Global water: 97% seawater, 3% freshwater. Of the freshwater 87% not accessible,13% accessible (0.4% of total).
  • Today more than 2 billion people are affected by water shortages in over 40 countries.
  • 263 river basins are shared by two or more nations;
  • 2 million tonnes per day of human waste are deposited in water courses
  • Half the population of the developing world is exposed to polluted sources of water that increase disease incidence.
  • 90% of natural disasters in the 1990s were water related.
  • The increase in numbers of people from 6 billion to 9 billion will be the main driver of water resources management for the next 50 years.
 


Role of Remote sensing and GIS in integrated water management:

Water resources are the basis of sustainable development of society and economy. It is recognized from the present situation that the key issue is the management. If powerful engineering and non-engineering measures are adopted, the problem is really possible to be well solved. In fact, RS, GIS and GPS can play important role to water resources management, such as surface water, groundwater, snow and ice investigation, dynamic monitoring of ecology and estimation of water amount necessary for keeping and recovering ecological environment, existing irrigation area investigation and irrigation planning, soil moisture and drought monitoring, investigation of soil salinisation, planing, monitoring and effect evaluation of returning cultivated and to forest or grassland, dynamic monitoring of desertification and soil erosion, variation of river course and sedimentation in lakes and reservoirs, site selection of water project and its planning, design, construction and management.

1. Water resources investigation:

Discharge in river channel can be accurately controlled by hydrological measurement, while the area of reservoir and lake can be determined by remote sensing. On the basis of that, water storage in lake and reservoir may be determined. This can also be worked out on the basis of multi -temporal (flood, middle and dry periods) remote sensing images and corresponding simultaneous water levels in the lake or reservoir under investigation. This method is much economic than under-water topographic measurement. Key problem is obtaining enough multi-temple remote sensing images. Groundwater is the most important reproduced natural resources, especially for livehood, animal husbandry and agriculture in arid regions. Remote sensing can provides the information about geology, hydrogeology, geomorphology and urban environment analysis. They are helpful for searching groundwater, provides clue for field investigation and improve successful possibility. For finding groundwater, the penetration of radar is helpful to directly find shallow-layer groundwater in the places with ancient river channel and the plain area in front of mountains.

The major description of ice -and-snow water resources is the scale of glacier, extent, thickness
and properties of snow cover. Remote sensing has the ability for the observation in these aspects. With the advantage of high temporal resolution of meteorological satellites, it is possible to distinguish cloud and snow cover due to the movement of cloud. Moreover remote
sensing can play more rule to snow monitoring, such as the determination of the percentage of
liquid water in snow pack, so as to more accurately estimate the water equivalent of snow pack
and to perform snow-melting runoff forecasting.

2. Delineation soil moisture:

The dielectric characteristics of object are the principle factor deciding emissivity. The dielectric constant of water is 80, while dry soil is 3. The difference is very significant. It means that the dielectric constant is very sensitive to soil moisture content. It makes the change of soil emissivity from 0.95 when soil is dry to 0.6 or less when soil is humid, namely the variation of 30% on natural emissivity of soil. The main objective parameter affecting emissivity is the volumetric moisture content in soil layer from ground surface to the depth of 5 cm. This is just the theoretical basis for measuring soil moisture content by remote sensing. The soil property, surface roughness and characteristics of vegetal cover must be also considered.

The soil moisture content measured on ground is the major basis for calibrating the parameters
in drought monitoring model by remote sensing. After measurement, transmission and processing, soil moisture contents are input the GIS-based information management system. Two-directional inquiry can be realized, namely, to inquire soil moisture content from the location of sampling point and to inquire location from soil moisture content. Combining with multi-intermediary measures, warning will be issued by sound, color and light when soil moisture content decrease to a certain degree. Besides the depletion of soil moisture content can be predicted by hydrological model. With these information, and also the distribution of crops and water demand during corresponding growth period, decision for drought against measures can be made, namely, from where and when to divert how much water to mitigate the drought situation.

3. Dynamic monitoring of desertification and effect evaluation after harness:

Desertification is related to natural conditions, especially the vibration of climate and water resources, also related to excessive human -being activities. Desertification reduces farmland area, vegetation cover and grassland area, is also one of sources of desert storm and atmospheric pollution.

Due to the difference of climate and water resources conditions, there are three types of desertification, i .e. desertification of sandy grassland, activation of fixed dune and invading of moving dune. Facing the serious situation that desertification is still developing, the emphasis of harness will be laid in four regions.

For estimation of ecology water demand, it is important to combine remote sensing with conventional data, such as temperature, precipitation, runoff and topography. The basic idea is
as follows.

(1) Ecological background  is made first according to topographic and climatic (temperature and precipitation ) conditions.
(2) Ecological background is overlaid on land use classification from remote sensing to reflect the effect of non-climatic factors, such as runoff and human-being activities. The resulting in secondary sub-area involves controllable and non-controllable areas.
(3) On the basis of detailed classification of land use, third-class area is produced, ecological water demand can be estimated through quantitative calculation for each kind of unit area.
4) Irrigation area investigation and development planning

In order to contend water, irrigation area is blindly developed in many places. The irrigation area from statistics way is smaller than the actual one. It results in water shortage in downstream basin. In order to realize comprehensive management of water resources for the whole basin, the irrigation area is important and basic information.

4) Monitoring of salinisation.

Salinisation is a typical phenomenon of ecological environment in arid and semi-arid regions. It has direct interpretation identification in remote sensing images for bare land. The bare land includes the farmland after harvest or just after seeding, the farmland with poor plant due to salinisation. The most obvious interpretation identification for saline-alkali soil is the spot with light white color. The boundaries of spots are naturally curved. The shape of spot is belted, netted, annular, arched, divergent or mottled. In the infrared images during rainy season, the light color sources from the surface of saltern above the salinized soil layer, without or with less salt efflorescence. The surface soil becomes solid grey-white crust because the soil is lake of organic matter, impervious and poor aerated. It is different from the soil without salinisation or the salinized soil after flushing by rainfall, with relatively higher reflectivity. In dry season, the light color of salinized soil is caused by the salt crust or salt efflorescence formed due to salt movement to surface. With the increase of salinity, the reflectivity also increases gradually in the region of wavelength from visible band to near-infrared band, presenting a characteristic curve with near -yellow hue, because the white salt efflorescence has the yellow soil as its background.

Among the interpretation identifications of salined soil, hue is the most important one, but the shape identification in remote sensing image is also important. Such as the white spot on the both sides of ancient river channels are belted, those in river beach on low highland of sprindle,
those around depressions are annular, those on slope are of stretch and those in the boundary
of bursting fan are belted.

At present, remote sensing is very effective for monitoring blue green alga due to eutrophication in lakes and reservoirs and red tide along the coastal area. With the sampling on water surface, the water quality classification into five grades can be roughly done. In general it is carried out by the multi-band composition of ETM+ digital images. Which bands would be used are decided according to the major pollutants in the water body under investigation. The quantitative determination of various chemical elements by means of high spectrum is a forward research subject in the world.

5) Planning, construction and management of water project:

Apart from the consideration of hydrological factors and economic evaluation, the site selection of reservoir and key water control project must consider the topography and the geological evaluation which can be done by remote sensing and GIS. The planning of water diversion project can be performed on the digital platform. Remote sensing is the major source of data and information into GIS-based database, the spatial analysis and on-line virtual reality technology can play their important role on this basis.

6) Real-time monitoring and management system of water resources:

Due to the importance of water resources and extensity and complexity of its information, it is very necessary to establish a special system for real-time monitoring and information management to provide basis for decision-making on an integrating information platform.

The data of information sources from remote sensing and conventional measures are real-time data and historical data. Information is managed by GIS and can be used together through network System consists of four sub-systems, i.e. data acquisition, data transmission, data processing and decision-making support system (DSS). It can automatically acquires real-time data of hydrological data including rainfall, discharge and water elevation in river channel, lakes and reservoir, groundwater table, soil moisture content and so on, as well as water quality of surface water and groundwater.

In spatial database, there are real time data and historical data. The spatial data includes basic geographic data, such as water body, topography, land use, land cover, administrative boundary, communication, plant distribution, social -economic data, water resources data concerning utilization and development, such as water supply and demand.

Data processing includes the processing for remote sensing images and other data, also the update of database. In the respect of DDS, there are bank of models and expert knowledge; it can provide comprehensive and synthetic basis for decision making. The functions of the system are as follows.

A) Inquiry
Information inquiry can be carried out in two directions, namely to inquire attribute from location
on map and to inquire location from attribute or condition, rule and term.

B) Statistics
The statistics can be done both in time and space or according to the condition, rule and term.

C) Prediction and warning
Combining with special models, what is made are water resources prediction, storm-flood
forecasting, low flow prediction, soil moisture content forecasting, snow-melt runoff forecasting
and prediction of water supply and demand.

D) Web GIS
Web GIS is adopted for this kind of system in order to realize operation and transfer in distance
and in multi terminals including the figures in sector format.

E) Planning
The planning includes water resources utilization and development, irrigation development,
water project, agriculture distribution, returning farmland to forest or grass and so on.

F) Consultation
Consultation is often held for finding a solution concerning water resources management. This
system can no doubt provides information, alternatives and corresponding consequence for
decision making.

7) Delineation of new catchment areas:
A catchment area is an extent of land where water from rain or snow melt drains downhill into a body of water, such as a river, lake, reservoir, estuary, wetland, sea or ocean. The drainage basin includes both the streams and rivers that convey the water as well as the land surfaces from which water drains into those channels, and is separated from adjacent basins by a drainage divide.

The catchment acts like a funnel, collecting all the water within the area covered by the basin and channelling it into a waterway. Each drainage basin is separated topographically from adjacent basins by a geographical barrier such as a ridge, hill or mountain, which is known as a water divide.

The below stated studies will be an important aspect for the study:
·         Geomporphology
·         Lityhology
·         Structures/lineaments
·         Drainage/Hydrology

·         Base map

Thursday, 15 October 2015

Accurate Digital Terrain Model of Part of Rajgarh, M.P., India


The Linear Accuracy is almost 100% and the error is less than 0.5M.
This DTM generated from Cartosat - 1 Stereo images
Accuracy validated using DGPS points (which were collected through Field Survey)

Andhra Pradesh - Yield Forecast - Paddy Crop 2015 Kharif Season







Dark Green Areas are Non Crop Areas.

Monday, 14 September 2015

Yield Forecast - Bihar Paddy

Below is the Crop Health Index, which was derived from Satellite Images and Weather parameters.


By observing the above trend of Crop Health Index (CHI) of Paddy Crop in Bihar, the yield forecast/estimate will be the same as 2011 or 2013 according to the current conditions or trend.  RED line indicates the 2015 paddy for Bihar.  By looking at upcoming fortnights CHI, yield forecast can be updated and forecast above 90% accuracy

Sugarcane Areas in Punjab

Here below picture depicts the major sugarcane growing areas. Mapped using Remote Sensing Techniques using MODIS Satellite images.  Mapped using time series classification techniques.

Consider only big/continuous areas only.  Don't consider scattered single pixel areas.


District wise boundaries are overlaid to check the Spatial distribution of  Sugarcane areas in a particular district.

Saturday, 12 September 2015

Sugarcane Areas in Maharashtra


Above Green Colour Areas are Major Sugarcane growing Areas in Maharashtra

Source: MODIS Satellite Images

Friday, 4 September 2015

Wednesday, 19 August 2015

Management of Agricultural Crops using Remote Sensing Technique - At All Stages during Crop Growth


As-on-date the number of satellite missions dedicated to remote sensing (earth Observation) has increased significantly over the past decade and will further increase over decade and beyond.  The Remote Sensing technology provides timely and very cost effective information about the crops grown.  The satellites orbiting round the earth provide images of ground at frequent time intervals.  Earlier days we have to wait till revisit the area, but now-a-days the satellites can be programmed, so as to acquire the images of any area at required time.  This is very helpful in getting an image of thee area when specific growth stage of the crop is to be mapped or identify the damaged area during flooding, etc.

There are several satellites and sensors which are best for agricultural applications Examples are given below along with applications:

The below satellites and sensors are best suits for crop health monitoring due to its frequency of revisit (twice a day – MODIS & NOAA) and its coverage with low resolution of satellite images. And AWiFS is also includes for this application due to its coverage.

·         AVHRR (Advanced Very High Resolution Radiometer), on board NOAA satellite having 1.1 km resolution
·         MODIS (Moderate Resolution Imaging Spectroradiometer) on board Terra Satellite having 250M, 500M and 1Km resolution
·         AWiFS (Advanced Wide Field Sensor) on board Resource sat (IRS – Indian Remote Sensing Satellite P6) having 56M resolution and 740 km swath width, frequency of revisit is 5 days

The below satellites and sensors are best suits for acreage estimation studies at regional level or country level studies

·          ASTER is one of the five state-of-the-art instrument sensor systems on-board Terra a satellite with a resolution of 15M with revisit time of 16 days

·         LISS – III, RESOURCESAT-1 (IRS-P6) is envisaged as the continuity mission to IRS-1C/1D, with enhanced capabilities with a resolution of 23.5M with revisit time of 24 days

·         Landsat series are LANDSAT-1, LANDSAT-2, 3, 4, 5, and 7 were launched and LANDSAT-7 is currently operated as a primary satellite with 30M spatial resolution and 16 days revisit time.

The below satellites were designed for mapping of agricultural plots, in addition to GeoEye-1, World View-1&2, but these below satellites and sensors are good for regional level mapping of agricultural plots and also having the capability of programmed to acquire the images of any area at any point of time (some times this may obstruct because of climatic conditions)

·         LISS-IV Camera in RESOURCESAT-1 (IRS-P6) satellite is a multispectral high resolution camera with a spatial resolution of 5.8m.  This camera can be operated in two modes: Mono and Multi-spectral. In the Multi-spectral mode, data are collected in three spectral bands - 0.52 to 0.59 microns (Green (Band 2)), 0.62 to 0.68 microns (Red (Band 3)), 0.76 to 0.86 microns (NIR (Band 4)) with a swath of 23.9km

·         RapidEye constellation of five satellites stands apart from other providers of satellite-based geospatial information in their unique ability to acquire high-resolution, large-area image data on a daily basis. RapidEye system is able to collect an unprecedented 4 million square kilometers of data per day at 6.5 meter nominal ground resolution. Having 5 spectral bands  i.e. (Blue  (Band 1)), 0.44to 0.51 microns, (Green (Band 2)), 0.52 to 0.59 microns (Red (Band 3)), 0.63 to 0.685 microns, (Red Edge (Band 4)) 0.69 to 0.73 and  (NIR (Band 5)) 0.76 to 0.85)


In the case study we have used MODIS and monitored the crop during all stages of crop growth.  Case study will be published in upcoming articles.

Friday, 14 August 2015

Population Distribution Map - Using Remote Sensing & GIS Techniques

Population Distribution Data using Remote Sensing & GIS Techniques

High resolution, contemporary data on human population distributions are vital for measuring impacts of population growth, monitoring human-environment interactions and for planning and policy development. Moreover the population density of an area can be one of the most important determining factors for business and marketing planning. It is not enough to know how many consumers live in a specific state or city. It is important to know how many people live in a particular radius. This will allow planners to choose a location for a business that is accessible to the largest amount of people.  Generally, population maps available in simply GIS maps wherein Census population is either attached to a point or to a polygon of a location. There is no such product available in the industry, which can show the distribution of population in a realistic manner. A product is therefore required wherein business analysts could know the population using their own ‘Area of Interest’ or within a particular ‘Buffer Area.’
Our Expert team can generate these raster or gridded population distribution map for a city or a region at 5m/10m/20m/30m/50m/100m. It is the raster dataset of population totals based on administrative boundary data and population estimates associated with those administrative units. The resulting raster data is easier to analyze and display than the original scattered points. The base data could be on details as per the last published Census availability.  

Solution: Our Expert team has come up with a unique product wherein ‘ Latest Satellite images’ along with the ‘latest Census -Population Data’ have been used to create ‘Population Distribution Map’ The population distribution map shows only the pixels having some population. The uninhabited areas are shown as null or zero value. The population density of each pixel varies depending upon the spatial extent of residential areas as derived from the satellite image, and the population of the area as provided by Census data.

City wise Raster Population Grid - Pixel wise Population details

Thursday, 9 July 2015

Kharif 2015 Paddy Sowing Status - Haryana till end of June

Below picture depicts Paddy sowing status in Haryana state (district-wise vector map overlaid) till end of June.

I got tremendous views and appreciations on earlier article, thatswhy I have generated for Haryana Paddy Sowing status till end of June.


NOTE: Data generated at 1:5,00,000 Scale using MODIS satellite images



Friday, 3 July 2015

Kharif 2015 Paddy Sowing Status - Punjab till end of June

Below picture depicts Paddy sowing status in Punjab state (district-wise vector map overlaid) till end of June.



NOTE: Data generated at 1:5,00,000 Scale using MODIS satellite images

Thursday, 2 July 2015

Nigeria Land Use - Land Cover using Remote sensing Satellite Data

Highly qualified remote sensing professionals and created different Landuse – Landcover projects at different scales and resolutions of starting from city level to regional and country levels.

Nigeria Entire Country Landuse-Landcover

Lagos City Landuse Landcover

Legend



Monday, 18 May 2015

Urban Planning Using Space Based Technologies


Urban Planning Using Remote Sensing, GIS & Aerial Photogrammetry Technologies

Introduction
Planning is a widely accepted way to handle complex problems of resources allocation and decision-making. It involves the use of collective intelligence and foresight to chart direction, order harmony and make progress in public activity relating to human environment and general welfare. In order to provide more effective and meaningful direction for better planning and development necessary support of the organization has become essential. Hence the need for a suitable information system is increasingly being felt in all planning and developmental activities, whether these are for urban or rural areas. The positive aspects of urbanization have often been overshadowed by deterioration in the physical environment and quality of life caused by the widening gaps between supply and demand for essential services and infrastructure.
Urbanization is inevitable, when pressure on land is high, agriculture incomes are low and population increases are excessive, as is the case in most of the developing countries of the world. Urbanization has become not only of the principal manifestation   but also an engine of change, and the 21st century which has become the centre of urban transition for human society. In a way urbanization is desirable for human development. However, uncontrolled urbanization has been responsible for many of the problems, our cities experiences today, resulting in substandard living environment, acute problems of drinking water, noise and air pollution, disposal of waste, traffic congestion etc. To improve these environmental degradations in and around the cities, the technological development in relevant fields have to solved these problems caused by rapid urbanization, only then the fruits of development will reach most of the deprived ones.
The modern technology of remote sensing which includes both aerial as well as satellite based systems, allow us to collect lot of physical data rather easily, with speed and on repetitive basis, and together with GIS helps us to analyze the data spatially, offering possibilities of generating various options (modeling), thereby optimizing the whole planning process. These information systems also offer interpretation of physical (spatial) data with other socio-economic data, and thereby providing an important linkage in the total planning process and making it more effective and meaningful. Recent technological advances made in domain of spatial technology cause considerable impact in planning activities. This domain of planning is of prime importance for a country like India with varied geographic patterns, cultural activities etc. The purpose of using GIS is that, maps provide an added dimension to data analysis which brings us one step closer to visualizing the complex patterns and relationships that characterize real-world planning and policy problems. Visualization of spatial patterns also supports change analysis, which is important in monitoring of social indicators. This in turn should result in improving need assessment.


Urbanization in India:

Urbanization is an index of transformation from traditional rural economy to modern industrial one. It is a progressive concentration of population in urban unit. At the moment, India is one among the country of low level of urbanization. Number of urban agglomeration/town has grown from the year 1827 in the year 1901 to 5161 in the year 2001. During the last fifty years the population of India has grown two-and-a-half times, but urban India has grown nearly five times. In 2001, 306.9 million Indians (30.5%) were living in nearly 3700 towns and cities spread across the country, compared to 62.4 million (17.3%) who lived in urban areas in 1951. This is an increase of about 390% in the last five decades. This process of urbanization in India is shown in Figure 1. It reflects a gradual increasing trend of urbanization. India is at an acceleration stage of the process of urbanization and expected to increase to cover million and 533 million by the years 2011 and 2021 respectively.




Urban planning - Remote sensing & GIS:
In India, the complexity of urban development is so dramatic that it demands immediate attention and perspective physical planning of the cities and towns. The dynamic nature of urban environmental necessitates both macro and micro level analysis. Therefore, it is necessary and fundamental for policy makers to integrate like remote sensing into urban planning and management. Traditional approaches and technique designed for towns and cities may prove to be inadequate tools when dealing with present scenario in the cities. New approaches are required, and new methods must be incorporated into current practice. Until recently, maps and land survey records from the 1960’s and 70’s were used for urban studies, but now the trend has shifted to using digital, multispectral images. The trend towards using remotely sensed data in urban studies began with first-generation satellite sensors such as landsat MSS and WAS given impetus by a number of second generation satellites: Landsat TM, ETM+ and SPOT HRV. The recent advent of a third generation of very high spatial resolution (0.5 meter/pixel) satellite sensors is stimulating. The high resolution PAN and LISS III merged data can be used together effectively for urban applications. Data from IRS P-6 satellites with sensors on board especially LISS IV Mono and Multispectral (MX) with 5.8 meter/pixel spatial resolution is very useful for urban studies.
Advancement in the technology of remote sensing has brought miracle in the availability of the higher and higher resolution satellite imageries. They are IRS-P6 Resourcesat imagery with 5.8 meter resolution in multispectral mode, IRS-1D Pan image with 5.8 meter resolution, Cartosat-I imagery of 2.5 meter resolution with stereo capabilities, Cartosat-II with 1 m, IKONOS imageries of Space Imaging with 4 meter in multispectral mode and 1 meter in panchromatic mode, Quickbird imagery of Digital Globe with 61 cm resolution in panchromatic mode and so on. These high resolutions of the sensors provide a new methodology in the application with newly raised technical restrictions.
Apart from Cartographic applications, high resolution data will be useful in cadastral mapping and updating terrain visualization, generation of a national topographic database, utilities planning and other GIS applications needed for urban areas. The satellite will provide cadastral level information up to a 1:5,000 scale, and will be useful for making 2-5 meter contour map. The output of a remote sensing system is usually an image representing the scene being observed. Many further steps of digital image processing and modeling are required in order to extract useful information from the image. Suitable techniques are to be adopted for a given theme, depending on the requirements of the specific problem. Since remote sensing may not provide all the information needed for a full-fledged assessment, many other spatial attributes from various sources are needed to be integrated with remote sensing data.
This integration of spatial data and their combined analysis is performed through GIS technique. It is a computer assisted system for capture, storage, retrieval, analysis and display of spatial data and non-spatial attribute data. The data can be derived from alternative sources such as survey data, geographical/topographical/aerial maps or archived data. Data can be in the form of locational data (such as latitudes/longitudes) or tabular (attribute) data. GIS techniques are playing an increasing role in facilitating integration of multi-layer spatial information with statistical attribute data to arrive at alternate developmental scenarios.
Application of Remote Sensing technology can lead to innovation in the planning process in various ways;
1. Digitisation of planning basemaps and various layout plan has facilitated updating of basemaps wherever changes have taken place in terms of land development etc. Digital maps provides flexibility as digital maps are scale free. Superimposition of any two digital maps which are on two different scales is feasible. This capability of digital maps facilitates insertion of fresh survey or modified maps into existing basemaps. Similarly superimposition of revenue maps on basemaps with reasonable accuracy is great advantage compared to manually done jobs.
2. Since information and maps are available in digital format, correlating various layers of information about a feature from satellite imagery, planning maps and revenue maps is feasible with the help of image processing software like ERDAS Imagine, ENVI and PCI Geomatica, ILWIS. Such super imposed maps in GIS software like Map info, Geomedia, Arc View, Auto CAD Map and Arc GIS provide valuable information for planning, implementing and management in urban areas.
3. Remote Sensing techniques are extremely useful for change detection analysis and selection of sites for specific facilities, such as hospital, restaurants, solid waste disposal and industry.
An attempt has been made here to demonstrate the potentials of remote sensing techniques in base mapping, land-use and land-cover mapping, urban change detection and mapping, urban infrastructure and utilities mapping, urban population estimation, management.
Aerial photography and satellite data in urban studies:
Aerial photographs have long been employed as a tool in urban analysis (Jensen 1983, and Garry, 1992). In India, city planning has been largely confined to aerial photography. It is being used for generation of base maps and other thematic maps for urban areas as it is proved to be cost and time effective and reliable. Wealth of information pertaining to land features, land use, built up areas, city structure, physical aspects of environment etc. are available from the aerial photography. Various types of cameras and sensors black and white, color, color infrared are used for aerial photography. Because of security concerns related to aerial photography, the use of photogrammetric techniques was confined to smaller cities.
Aerial photographs provide information that can significantly improve the effectiveness of city and town planning and management in India. They are also relatively low in cost, accurate, reliable and can be obtained on desired scale, but they are not useful in large metropolitan areas.
Base maps for urban areas:
Base map, a pre-requisite for urban planners, refers to the large scale maps, which depict broad physical and cultural features. The base maps are produced at a scale ranging from 1:10,000 to 1:4,000 and 1:1,000/1:500 for specific urban applications. Base maps at a scale of 1:4,000 that were prepared by ground survey in 1969 and 1971 are available for some areas. But now base maps are being produced at scales ranging from 1:4,000 to 1:10,000 depending upon the specific urban applications for which they are prepared.
Base maps can be also made from orthophotographs for inaccessible areas that are difficult to survey, high altitude towns like Leh, Puri, Himachal Paradesh etc. In such situations, remote sensing has made information collection possible for base maps where field surveying has fallen shot due to prohibitive faction such as cost, timing and terrain. These base maps can provide the backbone for development of information that was previously unavailable to the community, urban regional, and natural resource planners and management. IRS P-6 (multispectral) data with 2.5 m/pixel spatial resolution can meet the ever-growing demand for current, accurate base maps at a scale of 1:5,000 for urban planning purposes and for development new residential sites.



Data Approach for the Study:
In the view of the consequence and inevitability of the study the incongruity may arise for the suitable data for the study to attain precise and cost effective output. The technical and logical approach with proper effort may give the answer of the quarries related to the data approach. Advancement in the technologies now provided us many options to choose for the best available data approach for the study. There are three basic datasets may be used for the study:
1.    Field Survey through DGPS and Total Station:
2.    Satellite Images , and
3.    Aerial Photographs
1)    Field Survey through DGPS and Total Station:
Surveying is a technology that uses instruments to measure the position relationships between points on land and express shapes, areas and other aspects by figures or drawings. The primary function of surveying instruments is to measure distances, angles and heights. There are two types of surveying instruments used today: the total station and the GPS system. The total station employs the electro-optical distance metering method, emitting laser beams to a target and detecting light reflected off it. It takes measurements by calculating the deviation of the wavelength of the reflected light. With the GPS system, measurements are taken by receiving signals from GPS satellites. Total stations are able to measure distances to an accuracy of 2-3 millimeters per kilometer, and angles to 1-second. Total stations when extremely high accuracy is required, such as in building and bridge construction; GPS systems in applications where errors on the order of millimeters to centimeters are permitted.
The collection of total station and DGPS data requires manual efforts and a lot of time. It could be helpful in the ground verification of the geographical features and point of importance.


2)    Satellite Images:
Satellites capture imagery in digital format, therefore, unlike aerial photography, the imagery can be used as more than a backdrop, although this is still the most common use for the imagery. Most satellite imagery is captured digitally in the visible, near-infrared and mid-infrared range of the spectrum, allowing soil types to be discerned, mineral deposits to be predicted and identified, and vegetation vigour to be assessed amongst others. In addition, because of the altitude at which the satellites are in orbit, the resulting imagery does not suffer from distortions around the edges of each image, and as such, terrain permitting, any distortions resulting from the off-nadir capture angle are consistent across the area. It is due to these features that satellite imagery is often easier to process and produce an accurate product. Added to this, the satellites are in continuous orbit capturing imagery across the globe which makes any portion of the world accessible for imagery capture at consistent time-intervals.
Potentially, high resolution satellite images offer significant cost savings when compared with aerial photography as a result of larger footprints (this characteristic means that less ground control, less processing and less model setting is required for the ortho-rectification process), more frequent revisit times and the potential for automatic feature change detection. The gap between aerial photography and satellite imagery is progressively being bridged. With respect to traditional satellite sensors, the use of the new high-resolution spectral sensors increases both the amount of information attainable on land cover at local scales and the geometric detail and accuracy. This imagery is therefore of substantial interest for mapping of complex urban areas.
Data from high-resolution sensors clearly offer exciting new opportunities for monitoring urban space. Most current photogrammetric methods still rely on the use of aerial photography. Yet new satellite sensors may satisfy some urban data requirements. Consider the present interest in IKONOS data, where US cities are increasingly using single-date panchromatic imagery instead of aerial ortho-photos for updating existing data layers such as roads, houses of their spatial information system.
Demerits:
Though the satellite images are most popular data among the city planners but it has many major drawbacks. These are
  1. The coverage of the area of an image is very high in comparison to the aerial photographs so the ground details are very low.
  2. When the term resolution is used the satellite image in its advance version have maximum resolution is of 0.50m but the aerial photographs have micrometer resolution.
  3. The accuracy level in aerial photo graphs is comparatively higher than the satellite images because the resolution and ground details are high in aerial photographs.
  4. The ortho-photographs are distortion free and have more vericaly corrected view than the satellite image.
  5. The aerial images are haze free and available.
3. Aerial Photographs:
Aerial photographs have long been employed as a tool in urban analysis (Jensen 1983, and Garry, 1992). In India, city planning has been largely confined to aerial photography. It is being used for generation of base maps and other thematic maps for urban areas as it is proved to be cost and time effective and reliable. Wealth of information pertaining to land features, land use, built up areas, city structure, physical aspects of environment etc. are available from the aerial photography. Various types of cameras and sensors black and white, color, color infrared are used for aerial photography. Because of security concerns related to aerial photography, the use of photogrammetric techniques was confined to smaller cities.
Aerial photographs provide information that can significantly improve the effectiveness of city and town planning and management in India. They are also relatively low in cost, accurate, reliable and can be obtained on desired scale, but they are not useful in large metropolitan areas.
Urban hydrology:
The urban agglomerations in India are facing at least four hydrological problems, i.e, the mobilization of sufficient volume of water for domestic and industrial consumption, urban water pollution and quality, flood control and urban storm water run-off disposal.
Indian cities face problems of insufficient water for domestic & industrial purposes, poor water quality & inadequate urban storm water runoff disposal. However, Runoff cannot be directly measured by remote sensing techniques. The role of remote sensing in runoff calculation is generally to provide a source of input data or as an aid for estimating equation coefficient and model parameters. The remote sensing techniques are also being applied in obtaining information pertaining to surface water quality parameters, soil, drainage, land-use, ground water, and slope of catchment or watersheds relevant to carry runoff and water estimation studies. The GIS technology has the ability to capture, store, manipulate, analyze and visualize the geo-referenced data. On the other hand hydrology is inherently spatial and distributed hydrological models have been large data requirements. The integration of GIS and hydrology involves three major components: 1. Spatial data construction, 2. Integration of spatial model layers, 3. GIS and model interface.
Waste water infrastructure planning:
Operation of wastewater management is one of the most expensive utilities for the urban population. Expanding and maintaining a very large and rapidly aging wastewater collection system is a major problem facing many large cities. The rapid growth of population in the major towns of country and an ever increasing pollution load in the rivers called for an attention of the responsible government bodies to look into the matter of assessing the capacity of present sewerage system and to plan the same for future. Populations in the cities are rapidly increasing and are expected to double during the next 30 years. The existing collection and treatment systems must be expanded to reduce pollution to the environment and to improve living conditions in urban centers.
Geographic Information System (GIS) provides logical approach to understand the location significance of the information with its spatial location also referred as “spatial information”. An accurate map and a related list of information linking to the points, lines, polygons and symbols in the map can be considered as the principles of the GIS system.
GIS has been an integral part of the wastewater system planning process. The analysis capabilities of GIS coupled with satellite imagery allowed engineers to develop sewer system master plans more quickly than previous traditional methods. A computerized base-map of the GIS system can provide vital data for the design of sewerage by locating the nodes of connection between buildings to the sewerage pipe network. The population number or the measurement of the floor-space areal size of the buildings provide the flow-rate.GIS base maps and data developed during the project provide a foundation for the development of future planning and management tools such as hydraulic modeling, infrastructure mapping, maintenance management, and integration with GPS and field survey data.
Effective traffic management:
The transportation network is an important infrastructure element of the whole urban area. It allows connectivity and movement of people, traffic and goods both within and between urban centres. RS data can be used effectively for urban transportation network management. All roads with a width of 3m or more can be seen on high resolution (IKONOS) satellite data; such data facilitate the identification of roads that need to be widened to ease congestion. Using satellite images, road information can be updated and the approximate width of a road can be determined.
Solid and hazardous waste: 
Solid waste is a potential nightmare for India’s large and growing population, due to inadequate and legislative instruments and to the deplorable organisational and financial capabilities of local urban governments. The informal sector should be organised and the private sector should participate more widely in collection and recycling of solid waste.
In this context, the most acceptable strategy for solid waste management is first to categorize waste streams as biodegradable, non degradable and recyclables. Then the problem is where to dispose of it and it is not easy to locate the disposal site. A geospatial database generated from remotely sensed satellite data could be used to help solve this problem. Efforts should be made to reclaim abandoned landfill sites.

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