Geography of Water Resources. Scope.

1. Distribution and Availability : Study of how water is distributed across different geographic regions, including its presence in oceans, rivers, lakes, groundwater, and glaciers.

2. Hydrological Cycle : Examination of the movement of water through evaporation, condensation, precipitation, runoff, and groundwater recharge.

3. Water Quality : Analysis of the physical, chemical, and biological characteristics of water, addressing issues like pollution and contamination.

4. Water Scarcity : Exploration of areas where water supply is insufficient to meet demand, often due to factors like population growth, climate change, and mismanagement.

5. Water Management : Study of strategies to conserve, allocate, and regulate water resources, including infrastructure like dams, reservoirs, and irrigation systems.

6. Water-related Ecosystems : Understanding the influence of water on various ecosystems, such as wetlands, rivers, estuaries, and coastal areas.

7. Human Impact : Examination of how human activities like agriculture, industry, and urbanization affect water resources and ecosystems.

8. Climate Change : Analysis of how changing climate patterns impact water availability, precipitation, and overall water resource management.

9. Transboundary Water Issues : Study of conflicts and cooperation between regions or countries sharing water resources, often leading to complex geopolitical considerations.

10. Sustainable Development : Focus on ensuring equitable access to clean water while balancing ecological, economic, and social needs for present and future generations.

11. Policy and Governance : Exploration of laws, regulations, and management practices aimed at protecting and sustaining water resources.

12. Water-related Hazards : Study of natural events like floods, droughts, and tsunamis, and their implications for water resource planning and disaster management.

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Supervised Classification

Image Classification in Remote Sensing Image classification in remote sensing involves categorizing pixels in an image into thematic classes to produce a map. This process is essential for land use and land cover mapping, environmental studies, and resource management. The two primary methods for classification are Supervised and Unsupervised Classification . Here's a breakdown of these methods and the key stages of image classification. 1. Types of Classification Supervised Classification In supervised classification, the analyst manually defines classes of interest (known as information classes ), such as "water," "urban," or "vegetation," and identifies training areas —sections of the image that are representative of these classes. Using these training areas, the algorithm learns the spectral characteristics of each class and applies them to classify the entire image. When to Use Supervised Classification: - You have prior knowledge about the c...

Image Transformation

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Isodata clustering

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Spectral Signature vs. Spectral Reflectance Curve

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REMOTE SENSING INDICES

Remote sensing indices are band ratios designed to highlight specific surface features (vegetation, soil, water, urban areas, snow, burned areas, etc.) using the spectral reflectance properties of the Earth's surface. They improve classification accuracy and environmental monitoring. 1. Vegetation Indices NDVI – Normalized Difference Vegetation Index Formula: (NIR – RED) / (NIR + RED) Concept: Vegetation reflects strongly in NIR and absorbs in RED due to chlorophyll. Measures: Vegetation greenness & health Uses: Agriculture, drought monitoring, biomass estimation EVI – Enhanced Vegetation Index Formula: G × (NIR – RED) / (NIR + C1×RED – C2×BLUE + L) Concept: Corrects for soil and atmospheric noise. Measures: Vegetation vigor in dense canopies Uses: Tropical rainforest mapping, high biomass regions GNDVI – Green Normalized Difference Vegetation Index Formula: (NIR – GREEN) / (NIR + GREEN) Concept: Uses Green instead of Red ...

Vineesh V, Geography

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