Water retention in soil can be understood as the water retained by the soil after it runs through the soil pores to join water bodies such as groundwater or surface streams. Pores in the soil can be defined as the air-spaces that exist in between soil particles.
Water retention is mainly dependant on the particle size of the soil. The finer the soil particles, the higher the chance that water molecules shall hold on to soil particles, such as in clay, as opposed to sandy soil, that has large and coarse particles that are not cohesive.
The water retention by soil is critical for plants and acts as the chief source of moisture for it in almost all habitats. Other than percolation through the soil, soil moisture can also deplete due to evaporation directly from the soil and by transpiration by plants.
As based on the size of the soil particles, there are four classificatory systems for the identification of soils (J. Mariamma, 2010) –
- US Bureau of Soil Classification
- International Classification
- M.I.T Classification
- Indian Standard Classification
The Indian Standard classificatory system was formulated originally for the classification of soils primarily for engineering purposes. This is because the draft for soil classification was prepared by the Soil Engineering Sectional Committee and was approved by the Civil Engineering Division Council.
The final draft was adopted by the Bureau of Indian Standards on December 19th, 1970. This system divides soils into three broad categories based on the properties of soil particles (Bureau of Indian Standards, 2004) –
i) Clay – the particles are microscopic to sub-microscopic and exhibit plasticity, allowing it to retain the most water.
ii) Silt – the particles are fine grains, but exhibit less plasticity, making this form retain lesser water.
iii) Sand and Gravel – aggregates of comparably larger particles that are coarse and loosely bound thus lacking cohesion. The least water retention is possible in this form of soil.
Different topographic and climactic patterns result in varied behaviour of soils and thus require a variety of approaches to analyze and implement soil management techniques for water retention. Soil can sometimes pose problems for not being as desired, and these problems can broadly be grouped under chemical and physical problems (National Agricultural University, NAU, 2013).
Chemical problems include high salinity or acidity in soils, along with the presence of other toxic chemicals such as phosphorous in soil (NAU, 2013). This problem becomes especially pertinent in agriculture where crop yield or productivity could dwindle due to chemicals used in the agricultural process such as pesticides and herbicides.
Among a large gamut of solutions and applications, the most common one is the use of ecologically beneficial green manure. Agricultural soil should also be frequently and properly drained to achieve effects such as the leaching of saline moisture in soils.
The physical problems can involve soil that is not able to contain much water due to lack of cohesion or due to a rigidity that can occur owing to encrustation, or a very clayey surface. Shallow depth of soil, soil that is too clayey, or the presence of hard opaque surfaces underneath can also present problems to water retention and there can be water-logging when too much water is added to soil.
These require artificial solutions to soil management that frequently involves the mixing of soil with other different forms of soil. Incorporating organic matter and regulating drainage are also frequently applied solutions.
There are various methods to enhancing the water retention capacity of soil. Some methods are more traditional, and also conventional, while some involve the utilization of technology. While most of technological investment regarding water retention in soils involves technologies for enumeration and generation of data, technological solutions can vary from simple, affordable, everyday solutions to solutions utilizing high-end technology.
Some of the simple solutions include application of organic solutions such as drought resistant crop varieties and organisms that increase the fertility of soil, management and design of irrigation according to soil properties, application of biochar – produced from biomass for low-cost carbon sequestration in soil – making soil less porous, use of the roots of plants that grip soil, and application of natural by-products such as poultry litter that provide greater cohesiveness to soil.
The solutions can also range towards using complex technologies such as mapping the global water cycle in relation to water retention in soil, and preparation of dietary fibres that have high water-holding capacity from food sources used in soil. There is however, a leaning in technological progress in engineering water retention in soil to introduce organic elements in the soil instead of inorganic matter.
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[wptelegram-join-channel link=”https://t.me/s/upsctree” text=”Join @upsctree on Telegram”]2021 WEF Global Gender Gap report, which confirmed its 2016 finding of a decline in worldwide progress towards gender parity.
Over 2.8 billion women are legally restricted from having the same choice of jobs as men. As many as 104 countries still have laws preventing women from working in specific jobs, 59 countries have no laws on sexual harassment in the workplace, and it is astonishing that a handful of countries still allow husbands to legally stop their wives from working.
Globally, women’s participation in the labour force is estimated at 63% (as against 94% of men who participate), but India’s is at a dismal 25% or so currently. Most women are in informal and vulnerable employment—domestic help, agriculture, etc—and are always paid less than men.
Recent reports from Assam suggest that women workers in plantations are paid much less than men and never promoted to supervisory roles. The gender wage gap is about 24% globally, and women have lost far more jobs than men during lockdowns.
The problem of gender disparity is compounded by hurdles put up by governments, society and businesses: unequal access to social security schemes, banking services, education, digital services and so on, even as a glass ceiling has kept leadership roles out of women’s reach.
Yes, many governments and businesses had been working on parity before the pandemic struck. But the global gender gap, defined by differences reflected in the social, political, intellectual, cultural and economic attainments or attitudes of men and women, will not narrow in the near future without all major stakeholders working together on a clear agenda—that of economic growth by inclusion.
The WEF report estimates 135 years to close the gap at our current rate of progress based on four pillars: educational attainment, health, economic participation and political empowerment.
India has slipped from rank 112 to 140 in a single year, confirming how hard women were hit by the pandemic. Pakistan and Afghanistan are the only two Asian countries that fared worse.
Here are a few things we must do:
One, frame policies for equal-opportunity employment. Use technology and artificial intelligence to eliminate biases of gender, caste, etc, and select candidates at all levels on merit. Numerous surveys indicate that women in general have a better chance of landing jobs if their gender is not known to recruiters.
Two, foster a culture of gender sensitivity. Take a review of current policies and move from gender-neutral to gender-sensitive. Encourage and insist on diversity and inclusion at all levels, and promote more women internally to leadership roles. Demolish silos to let women grab potential opportunities in hitherto male-dominant roles. Work-from-home has taught us how efficiently women can manage flex-timings and productivity.
Three, deploy corporate social responsibility (CSR) funds for the education and skilling of women and girls at the bottom of the pyramid. CSR allocations to toilet building, the PM-Cares fund and firms’ own trusts could be re-channelled for this.
Four, get more women into research and development (R&D) roles. A study of over 4,000 companies found that more women in R&D jobs resulted in radical innovation. It appears women score far higher than men in championing change. If you seek growth from affordable products and services for low-income groups, women often have the best ideas.
Five, break barriers to allow progress. Cultural and structural issues must be fixed. Unconscious biases and discrimination are rampant even in highly-esteemed organizations. Establish fair and transparent human resource policies.
Six, get involved in local communities to engage them. As Michael Porter said, it is not possible for businesses to sustain long-term shareholder value without ensuring the welfare of the communities they exist in. It is in the best interest of enterprises to engage with local communities to understand and work towards lowering cultural and other barriers in society. It will also help connect with potential customers, employees and special interest groups driving the gender-equity agenda and achieve better diversity.