MEV 015: Unit 04 - Soil Quality and Its Pollution

-

Unit 4: Soil Quality and Its Pollution

4.1 Introduction

Soil is one of the most important natural resources. It supports plant life, provides nutrients, stores water, and plays a major role in agriculture and the environment. However, due to various natural and human activities, soil quality is degrading. Understanding soil quality and soil pollution is important for sustainable agriculture, food security, and environmental health.

4.2 Objectives

This unit aims to help learners understand what soil is, its properties, how it is classified, and how pollution affects soil. By the end of the unit, learners will be able to describe different types of soil, their characteristics, sources of soil pollution, its effects, and ways to protect soil health.

4.3 Characteristics of Soil

Soil is made up of minerals, organic matter, air, and water. Its properties vary depending on the materials it is formed from and the processes acting on it.

Properties of Soil

Soil properties can be physical (like texture, structure, color, and porosity), chemical (like pH, nutrient content), and biological (presence of microbes and organic matter). These properties influence plant growth and soil fertility.

Influence of Weathering on Soil Formation

Soil is formed through weathering — the breakdown of rocks by wind, water, temperature, and biological activity. Over time, weathering creates fine particles that mix with organic matter to form soil.

Soil Profiles and Horizons

A soil profile shows different layers of soil, called horizons. These include:

·         O Horizon: Organic layer (decayed leaves, plants)

·         A Horizon: Topsoil (rich in nutrients and organisms)

·         B Horizon: Subsoil (less organic matter, more minerals)

·         C Horizon: Weathered rock

·         R Horizon: Bedrock (hard rock below soil)

4.4 Different Kinds of Soil

Soils differ from place to place depending on climate, vegetation, and geology. Common types in India include alluvial soil, black soil, red soil, laterite soil, desert soil, and mountain soil.

4.5 Soil Classification

Soils are classified based on their texture, composition, pH, and nutrient content. Classification helps in choosing suitable crops and land management practices.

4.6 Saline Soil

Saline soils have a high amount of soluble salts, especially in arid and semi-arid regions. These soils can harm plant growth, reduce crop yield, and are often caused by poor irrigation practices or overuse of chemical fertilizers.

4.7 Alkaline Soil

Alkaline soils have high pH levels and excess sodium. These soils are hard and poorly drained. Crops do not grow well in such soils unless treated properly with gypsum or other soil amendments.

4.8 Soil Pollution

Causes

Soil pollution happens when harmful chemicals, waste, or pollutants mix with soil and degrade its quality. Main causes include:

·         Excessive use of fertilizers and pesticides

·         Industrial waste dumping

·         Improper disposal of plastics and garbage

·         Oil spills and chemical leaks

·         Urbanization and deforestation

Major Pollutants

Common pollutants are:

·         Pesticides and fertilizers

·         Heavy metals like lead, mercury, and arsenic

·         Industrial chemicals

·         Plastics and non-biodegradable waste

4.9 Soil Pollution and Agriculture

Chemical Pollution

Excessive use of chemical fertilizers and pesticides can kill helpful soil organisms, reduce soil fertility, and contaminate crops.

Metal Pollution

Heavy metals can enter the soil through industrial waste, vehicle emissions, and sewage. These metals accumulate in plants and enter the food chain, harming humans and animals.

Mining and Soil Pollution

Mining activities disturb land surfaces and release toxic materials into the soil, affecting vegetation and making land unusable.

Effects of Soil Pollution

Soil pollution affects:

·         Crop productivity and soil fertility

·         Groundwater quality through leaching of pollutants

·         Human health through contaminated food

·         Ecosystems by disturbing soil organisms and plant life

Let Us Sum Up

In this unit, we learned that soil is a valuable resource that supports life. Various types of soil exist with different properties. However, soil pollution caused by chemicals, heavy metals, and human activities harms agriculture, health, and the environment. Understanding soil characteristics, sources of pollution, and their effects is necessary for protecting and managing soil quality for future generations.

 

Comments

Post a Comment

Popular Posts

Jcert Class 8 Daffodil Chapter 1a: The Naive Friends Solutions

-
Chapter 1a : The Naive Friends Answer the following questions: 1. Which questions made Keshav and Shyama curious about the egg? Ans.         How did the chick come out? How big would the eggs? How many? What colours would they? What did they eat? Such types of questions made Keshav and Shyama curious about the egg. 2. What three things did the children do to protect the eggs? Ans.         The children done three things are: (i)          Adjustment of food. (ii)        Adjustment of water. (iii)      Adjustment of roof. 3. Why did Keshav think of making a cushion for the eggs? Ans.         When Keshav saw the egg on direct sun light, he thaught making a cushion for the eggs. 4. What excuse did Keshav give for not showing the eggs to Shyama? Ans.     ...
Read more

Jcert Class 8 भाषा मंजरी Chapter 3 मित्रता Solutions

-
अध्याय - 3 : मित्रता 1. आप किस प्रकार कह सकते हैं कि मित्रों के चुनाव की उपयुक्तता पर हमारे जीवन की सफलता निर्भर करती है? उ. मित्रों के चुनाव की उपयुक्तता पर हमारे जीवन की सफलता निर्भर करती है क्योंकि संगति का गुप्त प्रभाव हमारे आचरण पर पड़ता है और यदि हमें अच्छी संगति, अच्छे मित्र मिलते हैं तो वे हमें सफलता की ओर ले जाते हैं जबकि बुरी संगति हमारे जीवन को खाक में मिला देती है।  2. 'विश्वासपात्र मित्र जीवन की एक औषध है।' आशय स्पष्ट कीजिए। उ. 'विश्वासपात्र मित्र जीवन की एक औषध है'- ऐसा इसलिए कहा गया है कि यदि हमें विश्वासी मित्र मिल गया तो हम अपने जीवन में चाहे जैसा भी कदम उठाएँ, उस कदम की आलोचना करके वह हमें सही दिशा की ओर उन्मुख करेगा। हम अपनी गलती रूपी बीमारी को उसकी आलोचना रूपी औषधि से दूर कर सकेंगे।  3. मित्र का चुनाव करते समय हमें किन बातों का ध्यान रखना चाहिए? उ. मित्र का चुनाव करते समय हमें निम्नलिखित बातों का ध्यान रखना चाहिए हमारे अच्छे विचारों (संकल्पों) को दृढ़ करने वाला हो। हमें दोषों और त्रुटियों से बचाए। हमारे सत्य, पवित्रता ...
Read more

Jcert Class 8 भाषा मंजरी Chapter 8 अमरूद का पेड Solutions

-
अध्याय - 8 : अमरूद का पेड 1. लेखक को क्यों लगता है कि इन सब पिछड़े खयालातों का हमारे घर में गुजर नहीं हो सकेगा। उ. अमरूद के पेड़ को देखकर सबसे पहले बाबू कन्हैयालाल की बूढ़ी पत्नी ने एक दिन टोका कि पश्चिम की तरफ अगर मकान का मुखड़ा हो और सामने ही अमरूद का पेड़ तो 'राम-राम बड़ा अशुभ होता है और माँ के चेहरे पर थोड़ा-सा भय दिखा पर लेखक को विश्वास था कि इन सब पिछड़े खयालातों का हमारे घर में गुजर नहीं हो सकेगा क्योंकि उसके घर के लोग आधुनिक विचारधारा के थे उसकी माँ सत्याग्रह के दिनों में अजमेर में लम्बा जेल कर चुकी है। पिताजी खुद राजनैतिक सामाजिक उदारता वाले आदमी थे। बुआ ने विवाह नहीं किया था, पढ़ने-लिखने में ही अपनी सम्पूर्ण जिन्दगी लगा दी और समाज कोई चुनौती देने का साहस नहीं कर सका। साथ ही परिवार के सभी लोगों में पिछड़ेपन के प्रति भर्त्सना का भाव था। 2. अमरूद के पेड़ की छाया किस प्रकार लेखक को उनके भाई-बहनों के साथ जोड़ती है ? उ. अमरूद के पेड़ की छाया लेखक को उसके भाई-बहनों के साथ जोड़ती है। वे सभी अमरूद की छाया में बेंत की कुर्सियों पर बैठ चर्चाएँ करते थे जिससे उनके बीच...
Read more