eChapters

Introduction

Overview of the Chapter’s Focus on Agroecology and Soil Sustainability

The ecology and biodiversity of our globe are being threatened by human activity, notably unsustainable agriculture methods. This chapter explores the vital function of agroecology, the intersection of ecological and agricultural concepts, in promoting sustainable farming systems. Soil sustainability, essential for effective and resilient agrarian operations, is critical to this strategy. Here, we give an overview of these key terms and talk about the pressing need to switch to sustainable agriculture methods to preserve the  health of the soil, increase food security, and create adaptable environments.

Introduction

More than three billion people are at risk of poverty due to land degradation caused by humans (Kansanga, Kerr, Lupafya, Dakishoni, & Luginaah, 2021). The implementation of Soil Sustainability Management (SSM) practices remains low among smallholder farmers, despite the fact that SSM has developed as a generally accepted technique to tackling soil degradation in Agro ecosystems (Kansanga et al., 2021). When it comes to food, water, energy, climate, biodiversity, and the provision of ecosystem services, soil plays a pivotal role in addressing these global environmental sustainability concerns (McBratney, Field, & Koch, 2014). The availability of food, fiber, clean water, and a varied landscape are all dependent on healthy soil.

Introduction

Soil plays a vital role in fulfilling fundamental human requirements, such as the provision of sustenance and water, while also serving as the primary medium for supporting biodiversity. The sustainability of soil in the 21st century is dependent upon not only the implementation of effective management practices by farmers, foresters, and land-planners, but also on government regulations, policies, marketing strategies, and subsidies (Mishra et al., 2017). The increasing influence of human activities on the Earth’s natural environment has led to significant global challenges concerning the interplay of planetary and public health (J. Huang et al., 2018).

Introduction

Waste management and soil sustainability are two critical aspects of environmental conservation and sustainable development. As our global population continues to grow and consume resources at unprecedented rates, it becomes increasingly important to manage waste effectively and preserve our soil health and productivity. Anthropogenic activities have consistently produced waste. The World Bank predicts that worldwide garbage production will rise to 70% by 2050 if no substantial actions are taken (Ghosh, 2020). This was not a significant problem when the world’s population was small; however, it is acquired as a major concern with industrialization and urbanization revolution. Lack of proper waste management has caused pollution of water, land, and atmosphere, as well as a significant effect on human health (Raza et al., 2022a; Raza et al., 2022b).

Introduction to Soil Restoration and Management

One of the most crucial elements for human survival is the availability of arable land. Desertification caused by land degradation has emerged as a serious global environmental threat to human well-being and sustainable development in recent years because of both climatic shifts and an increase in human activities that have direct impacts on soil. It has been widely alarmed by the United Nations Convention to combat desertification and has shown considerable interest in this issue (UNCCD, 2015). Soil degradation is used to describe the transformation of arable land into unproductive land because of natural processes, typically accelerated by human activity (Lal, 1993).

Introduction

Organic farming is a comprehensive approach to production management that promotes and improves Agro-health, ecosystems including biodiversity, biological cycles, and soil biological activity. It prioritizes management approaches above off-farm inputs, and agronomic, biological, and mechanical farming procedures are used rather than synthetic resources (Ajibade, Ayinde, and Abdoulaye 2020). The term “organic farming” refers to a production technique that excludes the use of artificially formulated fertilizers, pesticides, or growth regulators for agronomic practices or the use of different chemicals for livestock production, i.e., feed additives, growth promoters and antibiotics, etc. (M. Singh 2021).

Introduction

Global population growth has led to an increase in demand for energy, food, and other essentials, resulting in an increase in agricultural land. Poor farming techniques, urbanization, and a lack of soil management measures have negative consequences for agricultural soils, such as reduced soil fertility, migration of soil organisms, and loss of soil microbiota and ultimately loss of soil health(Mehmood et al., 2020; Omotayo and Babalola, 2021; Syed et al., 2022). In addition, fertilizers used in agriculture have an impact on soil quality and health. Soil fertility is defined as the ability of a soil to meet the physico-chemical and biological requirements of a plant for growth, reproduction and quality, taking into account plant and soil type, land use and climatic conditions (Abbott and Murphy, 2007; Tyagi et al., 2019).

Introduction

Agriculture contributes a vital part within the financial stability of smallest emerging nations such as Pakistan as well. The economic system of Pakistan is fundamentally based upon agriculture (Govt. of Pakistan, 2004-2005). The total surface of Pakistan approximately 796,095 km2, of which 8.3 million km2 are uncultivated and 22 million km2 are farmed (Govt. of Pakistan 2015 2016). Despite an average yearly increase of 2.7%, agriculture contributes 21% of Pakistan’s GDP (Govt of Pakistan, 2004–2005). Farming is a sector whose fundamental and commercial models combine. Agriculture’s importance to the economy may be examined through three distinct perspectives: 1) as a source of nutritious food for the country and raw materials for internal industry; 2) as a way to generate currency from abroad and 3) as a source of products and services for local industries and the global market (Govt. of Pakistan, 2015-16).

Introduction

Soil is a non-renewable resource that sustains life, providing ecosystem services such as biomass production, contaminants filtration, raw material supply, nutrient, and hydrological cycle (Panagos et al., 2020). It contributes about 95% to global food production (Borrelli et al., 2020). Soil is a major global biodiversity pool and a large carbon pool on Earth. Therefore, it plays a crucial role in regulating energy and mass flow and their transfer between the biosphere, lithosphere, hydrosphere, and atmosphere (Ferreira et al., 2021). Climate change and unsustainable management practices are threatening the soil’s natural capital resulting in soil degradation occurring simply from erosion to contamination and leading the soil to completely unproductiveness under severe conditions, leading to food insecurity (Ashoka et al., 2017; Syed et al., 2022)

The capacity of soil to function as a vital living system, within ecosystem and land use boundaries, to sustain plant and animal production, maintain or 

enhance water and air quality, and promote plant and animal health (Doran and

Zeiss, 2000). A healthy soil may function is as follows:

• Sustain biological activity, diversity, and productivity

• Regulate, store of nutrients and cycle water and, decompose organic

matter

• Filtering and buffering, degrading, mineralizing, immobilizing, and

detoxifying organic and inorganic materials

• Inactivate toxic compounds, suppress pathogens, protect water quality,

and enhance catchment soil health.

Introduction

Climate change is threatening food security globally. Countries like India are more vulnerable in view of the tropical monsoon climate and poor coping capacity of the small and marginal farmers. Several agricultural practices like indiscriminate use of agro-chemicals and crop residue burning contribute to emission of greenhouse gasses leading to warming of the atmosphere. Sequestration of carbon both in the vegetation and soil is the most effective means of mitigating GHG emissions. There are several strategies of soil carbon sequestration which can be adopted at farm level. These include: conservation agriculture, biomass recycling, crop rotations and use of organic amendments. One of the recent developments is the conversion of crop residue biomass into biochar and using the char as a soil amendment rather than directly using the crop residues. Several studies show that biochar has a long life in soil and is more effective in sequestering carbon besides improving other soil properties like water holding capacity and nutrient availability. In Indian conditions, there is an immense scope for converting millions of tonnes of crop residues which are not used as fodder into biochar and use the same for enriching soil carbon.

Introduction

Productivity has increased as a result of the significant industrialization that has occurred in India during the past 40 years. However, it has also had detrimental effects on the ecology, particularly in India where soil contamination is progressively becoming more severe. In addition to the effects of man and land use, soil is constantly adapting changes in environmental conditions. A characteristic of soil pollution is the decrease in soil productivity brought on by the presence of soil pollutants. Some changes in the soil will be temporary and reversible, while others will be permanent. Pollutants in the soil have a negative impact on the physical, chemical, and biological characteristics of the soil and decrease its production. Soil pollution is a result of a variety of factors, including pesticides, fertilizers, organic manure, chemicals, radioactive waste, abandoned food, clothing, leather goods, plastics, paper, bottles, tins, and corpses. Industrial waste contains chemicals including iron, lead, mercury, copper, zinc, cadmium, aluminum, cyanides, acids, and alkalis, among others, which either directly or indirectly enter the soil.

Introduction

Soil organic matter is an indispensible component of soil health management. It plays an important role in improving soil physical, chemical and biological environment. Soil health refers to the capacity of the soil in terms of physical, chemical and biological properties for maintaining ecosystem services. With respect to agricultural lands, soil health implies the capability of the soil towards improving crop growth and yield, while also supporting environmental sustainability. Some important determining properties of soil health maintenance are soil reaction, salinity or alkalinity, soil organic matter, soil texture, soil structure/aggregation, water holding capacity, porosity, internal drainage, and nutrient retention capacity. Simultaneously, the key properties maneuvering soil health are soil aeration, internal drainage, nutrient cycling, susceptibility to erosion etc. Except some of the basic properties (soil texture) and processes (soil erosion), most of the determinant properties and processes are maneuvered by the presence of soil organic matter. A healthy soil must have strong resistance to degradation processes and able to recover following a perturbation because of inherent resilience (Magdoff 2001).

Introduction

Rice straw is produced as a by-product of rice production at harvest. Agricultural Waste Burning (AWB) is a major contributor of air pollution in many countries, particularly in South Asia. Exposure to fine particulate matter less than 2.5 μm (micrometer), also known as PM 2.5, released by AWB can cause premature mortality due to respiratory and cardiovascular diseases (Brauer et al.,2012). Combine Harvesters used on the spring rice crop leave behind stubble and straw on the field (Sidhu et al., 2007). Farmers burn the rice residue while preparing the field for wheat sowing season that follows. Further, migrant labour from neighbouring states of Bihar and Uttar Pradesh has decreased (Sirhindi, 2019), and resulted in an increase in the cost of agricultural labour during the rice harvest season (Sharma,2018). Farmers find it both convenient and economical to burn residue to clear and prepare their fields for the next crop. In 2018, over 20 million metric tons of rice residue was generated in Punjab, of which almost 10 million metric tons was subject to open-air burning (MoA, 2019). The time window between rice harvesting and wheat sowing is just 20 to 30 days towards the conclusion of the Kharif season, which is one of the primary reasons of crop waste burning (Balwinder et al., 2016).

Introduction

Microbial diversity is one of the main factors characterizing natural ecosystems; soil is considered one of the best storehouses of useful microorganisms in the world. Although the role of most of these microorganisms is still unknown, scientific progress is providing a better comprehension of the specific ecological functions of soil microorganisms (Ahmad, I.et al., 2008). Microorganisms in the rhizosphere soil play a key role in maintaining the soil fertility (Yadav et al. 2015), which is key for successful natural crop production to meet the increasing global organic food demand. Soil acts as a reservoir of air, water, and nutrients that is essential for plant growth. Only a few grams of soil contain hundred million to billion microorganisms. Bacteria are the most abundant microbes in soil followed by fungi; however, the actinomycetes are ranges in between bacteria and fungi. Other microbes that are found in smaller numbers are algae, cyanobacteria, protozoa, and nematodes. Soil gives the necessary support for anchorage to plant roots (Yadav et al. 2012; Bhaduri et al. 2015).

Introduction

Ideal plant health and productivity of a cropping system depends on an adequate amount of plant nutrients. Fertility of the soil refers to its capacity to support the production of crops. A productive fertile soil can support optimal plant growth, seed germination to plant maturity by providing adequate soil volume for plant root development, essential plant nutrients to meet the nutritional requirements of the plants, and encourage for the consequent plant structure. These attributes of the soil can be distinguished as inherent or dynamic soil quality indicators.Optimum plant health and productivity of a cropping system depends on an adequate supply of plant nutrients. The quantity of nutrients required by plants varies depending on many interacting factors including:

• Agronomic effects

• Soil properties

• Climatic condition

• Management practices

Nitrogen

Most commonly, complex organic compounds, ammonia, molecular nitrogen, nitrite, and nitrate are the forms of nitrogen found in soils. The physical and chemical conditions of the soil control the majority of the microbiological interconversions that change nitrogen.

Ammonia build-up, ammonia loss by volatilization, denitrification, nitrogen f ixation, and leaching losses of nitrogen are the primary changes that occur in submerged soils. The nutrition of rice is significantly impacted by these changes. Given the favourable circumstances for quick soil transformations and nitrogen loss, it is obvious that rice soils are nitrogen deficient.

Introduction

At a present time, Organic farming has an important priority in different areas due to worldwide in look of the growing need for pure and nutritious agriculture food and keep up the feasible and environmental pollution on long time associated with indiscriminate use of chemical fertilizer. The use of synthetic inputs in crop cultivation is necessary to meet the growing need for agriculture food in world. The natural fertilizers are made containing living or veiled cells or their strains of N2 fixation, P2 O5 solubilization bacteria. The biofertilizers are used for seed cramming, soil or vermicomposting region with the objective of rising quantity of such microbes and further those microbial processes which augment the obtainability of nutrients that can be easily digest by plants. Biofertilizers are playing higher role in increase soil productivity by f ixing atmospheric nitrogen, both, in relationship with plant roots and without it, solubilise and insoluble soil phosphorus and produces many plant growth substances in the soil.

Introduction

Manures are obtained from the plant residues, green manure, compost and animal wastes that are used as source of plant nutrients. They release nutrients after their decomposition. They essentially function as sustenance to the crops. They help in the proper cultivation of crops. The addition of manure enables the soil to hold more water. Organic manures have acids that dissolve the nutrients in the soil and make them available to the plants. manures can be grouped into bulky organic manures and concentrated organic manures. Brief dissection about manure given blow flow chart.

Bulky Organic Manure

Bulky organic manures are those materials of plant and animal origin, which contain small percentage of nutrients when added to the soil have tendency to decrease bulk density and to increase soil volume, thus providing better physical conditions for plant growth especially in coarse textured soils and also provide essential nutrients in smaller quantities than the chemical fertilizers. Characteristics of bulky organic manures:

Introduction

Problem soils are those that impede agricultural productivity owing to mineral stress, dryness, acidity, sodicity, waterlogging, etc. Vertisol, acid sulphate soils, saline-sodic soils, peat soil, and fine textured alluvial soils were the categories Beek et al., (1980) used to group the problematic soils. In addition to vast areas where deficiencies of zinc, phosphate, and iron, or excesses of iron, aluminium, and manganese limit rice yields, Ikehashi and Ponnamperuma (1978) observed that approximately 100 million hectares of land that are physiographical and climatically suitable for rice lie idle due to the soil toxicities caused by salt, alkali, acid, or organic matter. Problem soils can be broadly defined as those that have unfavourable conditions whether natural or artificially created that severely restrict the successful development of crops. Soil profiles with high groundwater levels and a less permeable argillic layer, degraded soils, sandy soils with low fertility, coastal soils that frequently flood, and laterites could all be categorised as problem soils. Without taking into account related soil functions, soil health is evaluated independently. It is also based on the f indings from a few soil tests for different criteria. 2015 has been recognized the International Year of Soils by the 68th UN General Assembly in recognition of the importance of soil health in all dimensions.