The action of surface water and groundwater in the chemical weathering or chemical erosion of soluble carbonate rocks such as magnesium carbonates (dolomites) and calcium carbonates (limestone) produces landforms that are called karst topography.
Geological features such as caves, sinkholes, underground rivers, barren and rocky ground and lack of surface water bodies are all results of the chemical processes of karst topography. The ontology of the term derives from its original reference to the Karst region in Slovenia, a limestone region near the Gulf of Trieste (Encyclopaedia Britannica).
Karst topography characteristically occurs when a layer of carbonate rocks occur just below surface soil, whose dissolution sometimes causes surface soil to funnel in, sometimes suddenly without warning.
The trigger for a collapse, Dr. Anthony Cooper, a geologist with the British Geological Survey claims, most commonly occurs due to changes in groundwater levels, or a sudden increase in levels of surface water.
In dry spells, when the water table is reduced, the withdrawal of groundwater levels leaves cavities once filled by water and silt might lead to a weakening of soil foundations. Also additions to the weights placed on surface soil or heavy downpours coupled with soil subsidence might also trigger a sinkhole.
As about 10 per cent of the Earth’s surface is comprised of karst topographies, it is not uncommon to find sinkholes. In fact the entire state of Florida in the US is classified as a karst landscape, such that insurance is a legal obligation for insurers to home owners.
The famous eroded cliffs at the western Irish coast, the caves in Slovenia, the 662 meter deep Xiaozhai tiankeng sinkhole in China, the 612 meter deep sinkhole Dashiwei tiankeng in China, the 530 meter deep Red Lake in Croatia, the 510 meter deep Minye sinkhole in Papua New Guinea and the Sotano Del Barro (410 meters) and the Sotano de las Golondrinas (372 meters) sinkholes in Mexico are some of the most significant examples of karst topographies (Jon Henley, 2013).
In India karst topography is present in the Vindhya region (mainly southwestern Bihar), the Himalayas (parts of Jammu & Kashmir, Robert Cave, Sahasradhara, the eastern Himalayas, areas near Dehradun), Pachmarhi in Madhya Pradesh, the surrounding coast near Vishakhapatnam, and Bastar in Chhattisgarh. It is reported that the 2004 tsunami originating near the Andaman and Nicobar islands might have caused sinkholes to appear all over certain islands of the Nicobar island group. Three Nicobar islands are particularly affected – Campbell Bay, Car Nicobar and Kamorta.
Sinkhole Mitigation
Mitigation measures for sinkholes basically bear the precautionary goals of filling sinkholes, maintenance of groundwater levels and checking contamination of groundwater, preventing surface water drainage into risk zones, and maintaining safety standards at risk zones . There are various approaches depending on the nature of the risk zone and the surrounding topography, land use and the climate.
The highest priority is provided to drainage in areas having karst topography and the approach is based on geological and engineering assistance that is site specific. Due attention is provided both to surface and ground water. It is necessary that inspections of risk areas take place on a regular basis, especially after major rain events. The fostering of vegetative buffer zones also works to prevent excessive run off of surface water, although it is advisable to plant native plant breeds and avoid the propagation of noxious plants and weeds.
Soil can also be investigated for assessing culpability of bearing karst features. Traditional methods such as boring soil and rock, and also percussion methods necessitates penetrating the ground in order to extract information on the underground geological properties of soil.
The invasiveness of these methods when dealing with the problem of sinkholes has led to a turn towards technological non-invasive methods for determining the properties of suspect soil. Some of these non-invasive methods include ground penetrating radar, resistivity imaging, seismic surveying and microgravity surveying. These on-site assessments are the necessary pre-requisite for engineering and development processes in suspect karst topographies.
Undersea Sinkholes
In 2016 scientists are reported to have measured the world’s deepest sinkhole in the South China Sea, toppling Dean’s Blue Hole in the Bahamas, previously thought to be the deepest sea sinkhole in the world.
The sinkhole in the South China Sea has been named the Dragon Hole and is 987 feet or 300 meters deep, located at a coral reef nearby the Paracel islands. A blue hole is an undersea sink hole that is visible from the surface due to the difference in the hues of the waters.
Such sinkholes are likely to provide undersea passages to cave systems and are usually steep-walled depressions. Due to the poor water circulation they are usually anoxic, meaning that oxygen percolation is very poor and diminishes after a certain depth, lending them averse to most life at great depths other than bacteria.
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- In the Large States category (overall), Chhattisgarh ranks 1st, followed by Odisha and Telangana, whereas, towards the bottom are Maharashtra at 16th, Assam at 17th and Gujarat at 18th. Gujarat is one State that has seen startling performance ranking 5th in the PAI 2021 Index outperforming traditionally good performing States like Andhra Pradesh and Karnataka, but ranks last in terms of Delta
- In the Small States category (overall), Nagaland tops, followed by Mizoram and Tripura. Towards the tail end of the overall Delta ranking is Uttarakhand (9th), Arunachal Pradesh (10th) and Meghalaya (11th). Nagaland despite being a poor performer in the PAI 2021 Index has come out to be the top performer in Delta, similarly, Mizoram’s performance in Delta is also reflected in it’s ranking in the PAI 2021 Index
- In terms of Equity, in the Large States category, Chhattisgarh has the best Delta rate on Equity indicators, this is also reflected in the performance of Chhattisgarh in the Equity Pillar where it ranks 4th. Following Chhattisgarh is Odisha ranking 2nd in Delta-Equity ranking, but ranks 17th in the Equity Pillar of PAI 2021. Telangana ranks 3rd in Delta-Equity ranking even though it is not a top performer in this Pillar in the overall PAI 2021 Index. Jharkhand (16th), Uttar Pradesh (17th) and Assam (18th) rank at the bottom with Uttar Pradesh’s performance in line with the PAI 2021 Index
- Odisha and Nagaland have shown the best year-on-year improvement under 12 Key Development indicators.
- In the 60:40 division States, the top three performers are Kerala, Goa and Tamil Nadu and, the bottom three performers are Uttar Pradesh, Jharkhand and Bihar.
- In the 90:10 division States, the top three performers were Himachal Pradesh, Sikkim and Mizoram; and, the bottom three performers are Manipur, Assam and Meghalaya.
- Among the 60:40 division States, Orissa, Chhattisgarh and Madhya Pradesh are the top three performers and Tamil Nadu, Telangana and Delhi appear as the bottom three performers.
- Among the 90:10 division States, the top three performers are Manipur, Arunachal Pradesh and Nagaland; and, the bottom three performers are Jammu and Kashmir, Uttarakhand and Himachal Pradesh
- Among the 60:40 division States, Goa, West Bengal and Delhi appear as the top three performers and Andhra Pradesh, Telangana and Bihar appear as the bottom three performers.
- Among the 90:10 division States, Mizoram, Himachal Pradesh and Tripura were the top three performers and Jammu & Kashmir, Nagaland and Arunachal Pradesh were the bottom three performers
- West Bengal, Bihar and Tamil Nadu were the top three States amongst the 60:40 division States; while Haryana, Punjab and Rajasthan appeared as the bottom three performers
- In the case of 90:10 division States, Mizoram, Assam and Tripura were the top three performers and Nagaland, Jammu & Kashmir and Uttarakhand featured as the bottom three
- Among the 60:40 division States, the top three performers are Kerala, Andhra Pradesh and Orissa and the bottom three performers are Madhya Pradesh, Jharkhand and Goa
- In the 90:10 division States, the top three performers are Mizoram, Sikkim and Nagaland and the bottom three performers are Manipur and Assam
In a diverse country like India, where each State is socially, culturally, economically, and politically distinct, measuring Governance becomes increasingly tricky. The Public Affairs Index (PAI 2021) is a scientifically rigorous, data-based framework that measures the quality of governance at the Sub-national level and ranks the States and Union Territories (UTs) of India on a Composite Index (CI).
States are classified into two categories – Large and Small – using population as the criteria.
In PAI 2021, PAC defined three significant pillars that embody Governance – Growth, Equity, and Sustainability. Each of the three Pillars is circumscribed by five governance praxis Themes.
The themes include – Voice and Accountability, Government Effectiveness, Rule of Law, Regulatory Quality and Control of Corruption.
At the bottom of the pyramid, 43 component indicators are mapped to 14 Sustainable Development Goals (SDGs) that are relevant to the States and UTs.
This forms the foundation of the conceptual framework of PAI 2021. The choice of the 43 indicators that go into the calculation of the CI were dictated by the objective of uncovering the complexity and multidimensional character of development governance
The Equity Principle
The Equity Pillar of the PAI 2021 Index analyses the inclusiveness impact at the Sub-national level in the country; inclusiveness in terms of the welfare of a society that depends primarily on establishing that all people feel that they have a say in the governance and are not excluded from the mainstream policy framework.
This requires all individuals and communities, but particularly the most vulnerable, to have an opportunity to improve or maintain their wellbeing. This chapter of PAI 2021 reflects the performance of States and UTs during the pandemic and questions the governance infrastructure in the country, analysing the effectiveness of schemes and the general livelihood of the people in terms of Equity.
Growth and its Discontents
Growth in its multidimensional form encompasses the essence of access to and the availability and optimal utilisation of resources. By resources, PAI 2021 refer to human resources, infrastructure and the budgetary allocations. Capacity building of an economy cannot take place if all the key players of growth do not drive development. The multiplier effects of better health care, improved educational outcomes, increased capital accumulation and lower unemployment levels contribute magnificently in the growth and development of the States.
The Pursuit Of Sustainability
The Sustainability Pillar analyses the access to and usage of resources that has an impact on environment, economy and humankind. The Pillar subsumes two themes and uses seven indicators to measure the effectiveness of government efforts with regards to Sustainability.
The Curious Case Of The Delta
The Delta Analysis presents the results on the State performance on year-on-year improvement. The rankings are measured as the Delta value over the last five to 10 years of data available for 12 Key Development Indicators (KDI). In PAI 2021, 12 indicators across the three Pillars of Equity (five indicators), Growth (five indicators) and Sustainability (two indicators). These KDIs are the outcome indicators crucial to assess Human Development. The Performance in the Delta Analysis is then compared to the Overall PAI 2021 Index.
Key Findings:-
In the Scheme of Things
The Scheme Analysis adds an additional dimension to ranking of the States on their governance. It attempts to complement the Governance Model by trying to understand the developmental activities undertaken by State Governments in the form of schemes. It also tries to understand whether better performance of States in schemes reflect in better governance.
The Centrally Sponsored schemes that were analysed are National Health Mission (NHM), Umbrella Integrated Child Development Services scheme (ICDS), Mahatma Gandh National Rural Employment Guarantee Scheme (MGNREGS), Samagra Shiksha Abhiyan (SmSA) and MidDay Meal Scheme (MDMS).
National Health Mission (NHM)
INTEGRATED CHILD DEVELOPMENT SERVICES (ICDS)
MID- DAY MEAL SCHEME (MDMS)
SAMAGRA SHIKSHA ABHIYAN (SMSA)
MAHATMA GANDHI NATIONAL RURAL EMPLOYMENT GUARANTEE SCHEME (MGNREGS)