Interview with Landslide Specialist Dr. Pankaj Jaiswal, Director Eastern Region, Geological Survey of India ...

Interview conducted by Malini Shankar, Digital Discourse Foundation

1. Please identify the areas vulnerable to landslides in India.

In India, about 0.42 million sq. km or 12.6% of land area, excluding snow covered area, is prone to landslide hazard. Out of this, 0.18 million sq. km falls in North East Himalaya, including Darjeeling and Sikkim Himalaya; 0.14 million sq. km falls in North West Himalaya (Uttarakhand, Himachal Pradesh and Jammu & Kashmir); 0.09 million sq. km in Western Ghats and Konkan hills (Tamil Nadu, Kerala, Karnataka, Goa and Maharashtra) and 0.01 million sq. km in Eastern Ghats.

Occurrences of landslide within these areas are controlled by various geological, geo-morphological, geo-hydrological and land cover features. My experience is that landslide is inevitable and can occur on any hill slopes depending on the intensity of trigger.

2. What is the estimated population in these landslide prone areas in India?

Total 146 districts are prone to landslide hazard. This include 16 districts each in Arunachal Pradesh (population 10.98 according to 2011 census) and Assam, 14 districts each in Kerala and J&K, 12 in Uttarakhand 11 in Maharashtra, 9 each in Manipur and Himachal Pradesh, 8 each in Mizoram and Karnataka and Goa, 7 each in Nagaland and Meghalaya, 4 each in Tripura and Sikkim, 1 in West Bengal etc*. This data is based on spatial occurrence of landslides in the country, ranked in terms of exposure of elements at risk. The population living within these hill districts are vulnerable to both direct and indirect landslide risk.

· Based on the response of the Director of Geological Survey of India Eastern Region, Digital Discourse Foundation extrapolated the population (14,29,69,388) that is vulnerable to landslides as per the district wise statistics of the Census of India 2011 because neither Geological Survey of India nor National Disaster Management Authority of the Government of India had ready figures of population at risk of landslides. Thus the population figure we have provided is at best an approximate figure.

3. What are the main causes / triggers for landslides in India?

The occurrences of landslide within India are controlled by various geological, geo-morphological, geo-hydrological and land use/ land cover features. The main causes are: In Himalayas the landslides are due to the weak rock-mass generated by the major tectonic thrusts, unfavorable geological structures (joint patterns), high relative relief, and loose glacial material on higher reaches. These slopes often generate landslides under natural conditions due to excessive bank erosion by rivers/drainages or daylighting of rock-overburden/structural discontinuities due to slope cutting for road building or other activities. (Daylighting means when we cut a slope then we exposes the rock/overburden contact). In Western Ghats and southern districts of the North-Eastern states, landslides are mainly due to excessive bank erosion by first/second order drainages or daylighting of rock-overburden due to slope cutting for road building or other activities.

in our country. In Himalayas slopes are also prone to earthquake-triggered landslides.

4. Does India suffer landslides more during El Nino or La Nina years?

We understand that El Nino leads to dry conditions and deficient monsoon in South Asia including India, whereas La Nina results in better than normal monsoon in India. It appears that it influences more on occurrences of floods or draughts. However, for landslides we have not seen any direct correlation.

5. All along the equatorial belt it appears La Nina has a greater trigger for landslides… your comments please.

From available literature it appears that countries like Kenya had witnessed landslides during 1997-1998 triggered due to extraordinarily heavy rainfall caused by El-Nino. As said earlier that landslides are triggered due to high intensity as well as prolonged rainfall in a region. If any weather phenomena have a potential of resulting heavy rainfall as well as moderate to high rainfall for long period, such weather can trigger landslides.

6. Are landslides triggered by La Nina in the Temperate zone countries / colder climes too?

Did not come across any literature on this.

7. If excessive moisture triggers landslides, then will melting of ice sheets (like in Greenland for instance) or melting of glaciers in say in Siberia trigger landslides? I request a climate change perspective here.

Yes, it’s true that excessive moisture trigger landslides. In 1997, snow melting triggered numerous landslides in Italy. But, in context of melting of ice sheets in Greenland or Siberia, these may lead to increase in sea level and the resulted cascading effects such as rise in base level of erosion in rivers causing excessive bank erosion and slope failures in lower reaches. We have witnessed one such effect in 2013 in Uttarakhand when the higher Himalayan reaches like Kedarnath have witnessed excessive rainfall, which otherwise is the zone of snowfall. This can be correlated to climate change wherein in the rainfall zone is being pushed northward. Excessive rainfall in higher Himalayan reaches, which houses loose morainic/glacial sediments, can always trigger landslides and debris flows. What happened in 2013 deluge in Uttarakhand is that the increase in river levels due to availability of water more than their carrying capacity has caused erosion of river terraces located at relatively higher level.

8. How do landslides manifest in flat land (non-mountainous terrain / areas)?

There are two situations: one a totally flat land in non-mountainous or plain terrain where landslide occurs as a lateral spreading due to either effect of liquefaction or subsidence. In large flat river terraces in mountainous regions landslide occur as subsidence and lateral spread due to removal of river bank toe by water erosion.

9. How does unsustainable development and human footprint impact on environment and trigger landslides? A subcontinental perspective please … touching up on all SAARC countries if possible.

SAARC includes Afghanistan, Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan and Sri Lanka. The countries such as Afghanistan, Pakistan, India, Nepal, Bhutan, and some parts of Bangladesh lie on Hindu-Kush-Himalaya regions. This region has fragile rock-mass that are vulnerable to mass movements. In recent times, the SAARC countries have witnessed increase in landslide disasters because of overexploitation of natural resources, change in climate, and increase in hill population and uncontrolled excavations resulting in a higher susceptibility of surface soil to instability, and higher vulnerability of the exposed population. In the latter half of the 20th Century, the increase in hill tourism, hydroelectric projects and increase of hill population because of the human desire for living in natural and serene environments have resulted in a rapid increase of infrastructure developments, such as roads and railroads, new settlements, etc. As a result of these developments more and more hill slopes are excavated ‘indiscriminately’ without following proper engineering standards and (are) left exposed. These untreated slopes often result in slope failures and develop into landslides of larger dimensions with passage of time.

10. How do landslides manifest in Desert ecosystems?

Did not come across any literature on this.

11. Please cite seismological triggers of landslides with anecdotal perspective and statistics – in India.

The landslide-prone Himalayan terrain also belongs to the maximum earthquake-prone zones (Zone-IV and V; BIS 2002) where earthquakes of Modified Mercalli intensity VIII to IX can occur, and thus, are also prone to earthquake-triggered landslides. The most recent example is the landslides triggered in the Sikkim-Darjeeling Himalayas due to 18 September 2011 Sikkim Earthquake. Another examples are: (i) Assam earthquake of 12^th June, 1897 that has triggered at least 27 landslides on the Shillong plateau itself, (ii) the magnitude 6.6 Uttarkashi earthquake of 20 October, 1991 that has resulted in about 150 landslides in Garhwal Himalaya, (iii) the Chamoli earthquake of 6.4 M_w in the Garhwal Himalaya occurred on 29^th March, 1999 and triggered 56 landslides within an area of 226 km², (iv) on 8^th October, 2005 a devastating earthquake of 7.6 Mw struck the lesser Kashmir Himalaya of Northern Pakistan and India and triggered more than 2000 landslides.

12. It is said many Pacific Rim countries like the Philippines use the technique of re-greening or reforestation to prevent landslides. But will it work in terrain with excessive moisture and humidity too? I request a climate change perspective here please. Is conservation the cornerstone of landslide prevention?

One of the most scientifically approved way of landslide mitigation is plantation or afforestation. In India, too we practice this and special type of grass such as vetiver grass is grown to prevent shallow slope failures. Some trees with long root is used for increasing root cohesion. In Nilgiris district, Tamil Nadu a large number of landslides occurred in cultivated areas in 1978/1979 and now with tea plants all over, the natural failures are less. It is also observed that trees like pine with small root and long shoot is not good for slope stability.

13. Please list the biggest landslides in India after independence.

In India landslides of all types and magnitude is available. Some landslides are very big in size such as Varuna Parvat landslide in Uttarkashi, Kaliasaur in Chamoli, Gayabari and Ambootia landslide in Darjeeling, Malpa and Tintola landslide in Pittoragarh etc. GSI has an inventory of more than 34000 landslides. But in terms of impact even small landslides such as Malin, Amboori, Marapallam etc were most devastating as they had caused huge casualties.

14. While La Nina creates landslides in India it is said El Nino brings drought desertification and water scarcity in India. But apparently El Nino ushers landslides in Sri Lanka and Afghanistan and La Nina makes these countries prone to drought and desertification … that means the reverse of what happens in India. My question is: how can lack of moisture trigger landslides in these two regions of the Sub continent outside India.

Sorry, I have no specific details on this.

15. India’s Western Ghats hosts a critical rail network bang in the middle of landslide prone wet evergreen rainforests… transporting millions of people and tonnes of material. Give us the disaster possibilities because of landslides in the Western Ghats. Can human beings actually fortify the mountain chain’s railway network from landslides? A Disaster risk reduction perspective please.

In Western Ghats, Konkan railway runs along the western coast, the Nilgiri toy train runs within Nilgiri hills and Kerala has rail network mostly along its coasts. These trains, particularly Konkan and Nilgiri rails are vulnerable to occasional small rock falls and minor debris slides. Yes, it is possible to successfully mitigates such landslide problems but the question is at how many locations and at what costs? It is learnt that along Konkan route several early warning systems have been deployed and also slope protection works have been carried out at few vulnerable locations.

16. Tell us if landslides occur in India’s island territories and what are the remedies or preventive measures?

It is learnt that there are few very minor landslides, mostly cut slope failures, in the Andaman and Nicobar islands. These can be easily controlled using minor structure mitigation measures.

17. Has India ever experienced submarine landslide in her territorial waters?

Did not come across any literature on this.

Malini Shankar

Expert interview with T.V. Ramachandra, Limnologist, Centre for Ecological Sciences, Indian Institute of Science, Bangalore

Interviewed by Malini Shankar, Digital Discourse Foundation

1. Please define and explain in very simple terms (for the understanding of the lay man) what is meant by soil carbon?

Soil carbon refers to the carbon content in the soil, is part of carbon cycle promoting the biological and physical health of soil. Vital constitute supporting the plant growth.

2. What are the sources of carbon in the soil?

Carbon enters the soil through decomposition of organic material. Bacteria converts the organic carbon to an inorganic carbon which are up taken by plants. Organic carbon enters the soil when organic material (plants, trees, leaves..) falls and decays with the microbial actions.

3. What are the anthropogenic sources of carbon in the soil?

Carbon gets to the atmosphere through emissions due to deforestation and also from the decomposition of organic carbon or organic matter.

4. What are the sources of carbon in the soil?

Plant litter or detritus due to plant senescence (i.e cell's power of division and growth) is the major source. Soil organic carbon is concentrated in the top soil, which consist of 0.5 to 3% organic carbon.

5. What are the natural sources of carbon in the soil?

CO₂ is removed from the atmosphere by plants during photosynthesis and through plant litter enters the soil and stored in the form of soil organic carbon.

6. What is the fallout of carbon in the soil?

Soil plays an important role in the global carbon cycle. Plant litter decay, which forms an food for bacteria, which respire and releases carbon dioxide back to the atmosphere. Also, carbon is released to the atmosphere with the burning of plants, the soil or fossil fuel.

7. Why is soil carbon contributing to Climate change? Kindly explain in simple terms – for the common man’s understanding.

There is scope for warming to increase the carbon dioxide release from soil to atmosphere with the enhanced microbial breakdown of soil organic matter. Such acceleration in carbon loss from soil could significantly exacerbate the soil carbon cycle feedback.

Emissions happen due to anthropogenic activities as discussed in the publications:

8. http://wgbis.ces.iisc.ernet.in/energy/paper/researchpaper.html#cc

Major cities – carbon footprint

http://wgbis.ces.iisc.ernet.in/energy/paper/GHG_footprint/index.html

Transportation sector

http://wgbis.ces.iisc.ernet.in/energy/paper/Mitigation-and-adaptation-strategy/index.html

Decentralised carbon footprint analyses

http://wgbis.ces.iisc.ernet.in/energy/paper/rser_carbon_footprint/index.htm

8. How can soil carbon in the soil be neutralised?

Afforestation or covering the soil with the vegetation cover would lower the emissions from carbon. Soil microbes and their metabolic activities influence land atmosphere carbon exchanges.

9. Does soil carbon trigger emissions which exacerbate Climate Change?

Importantly, climate change has both direct and indirect effects on the activities of soil microbes that feedback greenhouse gases to the atmosphere and contribute to global warming: direct effects include the influence on soil microbes and greenhouse gas production of temperature, changing precipitation and extreme climatic events, whereas indirect effects result from climate-driven changes in plant productivity and diversity which alter soil physicochemical conditions, the supply of carbon to soil and the structure and activity of microbial communities involved in decomposition processes and carbon release from soil.

10. But it also becomes peat at some stage which goes through geological stresses and eventually comes out as magma in volcanic vents? Large sulphur deposits from volcanic magma have a cooling effect as we know now. Does sulphur from volcanos even remotely neutralise carbon?

I have not studied this aspect

11. Are sulphur emissions unequal to anthropogenic factors of Carbon emissions?

Sulphur, Nitrous oxides are also greenhouse gases along with species of carbon (carbon dioxide, methane, etc.) Sulfur dioxide in the atmosphere is due to anthropogenic activities with fossil fuel burning – energy generation, industrial activities, etc.

12. Does forest leaf litter also contain carbon in the soil?

Forest leaf litter helps in enriching the soil carbon

13. Please tell us about soil fertility in forest areas.

Forests play a vital role in the biogeochemical and nutrient cycling. Soil formed for example in deciduous forest are fertile due to decomposing plant litter in every annual cycle. Forests do store carbon in leaves, trees and soil.

14. To sequester soil carbon is it necessary to neutralise carbon in forested soils too?

Increasing the total organic carbon in soil increases soil quality and would help in decreasing atmospheric carbon dioxide. The amount of organic carbon stored in soil is the sum of inputs to soil (plant and animal residues) and losses from soil (decomposition, erosion and uptake in plant and animal production).

15. Please give us a biodiversity perspective of how to neutralise / sequester soil carbon with Nature’s assets only.

Forests of the Western Ghats, one of the global biodiversity hotspots, have been steadily affected by human activities, especially since the introduction of agriculture. In traditional, community centered, pre-colonial land use, however, a sustainable balance was maintained between farmers and forests. This was facilitated through maintenance of a decentralized system of forest reserves, the sacred groves, in a mosaic of landscape elements which had shifting cultivation areas, secondary forests on fallows in different stages of vegetational succession, rice fields and spice gardens in valleys, and savannized lands as pastures. Network of natural water courses and swamps, covered with characteristic tree species of rarer kind would have been key feature of central Western Ghats. As historical records of Uttara Kannada testify, the pre and early colonial period up to mid-19th century was also one of richest wildlife as well. The many patches of sacred forests, often hundreds of hectares in extent, functioned as favorable pockets for persistence of several sensitive climax species of the Western Ghats, which could not easily re-colonize the fire burnt fallows and savannas. Their remains today are the relic forests, the subject of this paper.

State monopoly over forests, beginning with the British, early in the 19th century, spelt an end to the community-based landscape management. Most sacred groves, secondary forests and other unclaimed lands came under state monopoly as reserve forests. State driven and revenue oriented forest management policies focused mainly on timber extraction and on raising of tree plantations. Even the sacred groves of primeval nature were treated like any other forests. Whereas such relic forests, remaining isolated amidst human habitations suffered from extraction pressures from local people themselves, who were denied their traditional rights in the reserved forests, the larger groves of thinly populated areas got merged with secondary forests and lost their sacred value. Their remains today with rare relic species went almost unrecognized in conservation circles, until studies have been initiated from the angle of ecological history.

Our study at Kathalekan in Central Western Ghats, reveal that the forest is a mosaic of primary forest rich in relic trees like Dipterocarpus and Palaquium and a network of perennial streams and swamps sheltering Semecarpus kathalekanensis, Syzygium travancoricum, Myristica magnifica, Gymnacranthera canarica (the last three in threat categories of IUCN Red List). Persistence of these Western Ghat endemics, and relic species in this forest calls for serious attention from conservationists and forest managers to initiate programs immediately for recognizing and salvaging more fragments of such ancient forests that lie hidden amidst a sea of secondary forests. The fact that water course forests have not only rare species but also high biomass and greater carbon sequestration potential also calls for revision of forest management policies, as the innumerable stream courses of Western Ghats offer tremendous potential for carbon stocking per unit area while also bettering the hydrology of these mountains, which form the main watershed for the entire Indian Peninsula. Millions of subsistence farmers and other forest dwellers of Western Ghats can not only be partners in micro-level planning for prudent water use but also stand to gain in a big way from carbon credits for their new role as promoters and guardians of watershed vegetation. Rendering such service for mitigating global climatic change can also, same time, serve well the cause of relic forests and relic species in an otherwise much impacted biodiversity hotspot.

Details at: http://wgbis.ces.iisc.ernet.in/energy/water/paper/swampy_relic_forests/index.htm

16. What are the legal measures India has adopted to sequester soil carbon?

Of the total land area of 329 million hectares (Mha), 297 Mha is the land area comprising 162 Mha of arable land, 69 Mha of forest and woodland, 11 Mha of permanent pasture, 8 Mha of permanent crops and 58 Mha is other land uses. Thesoil organic carbon (SOC) pool is estimated at 21 Pg (petagram = Pg = 1 ×1015 g= billion ton) to 30-cm depth and 63 Pg to 150-cm depth. The soil inorganic carbon (SIC) pool is estimated at 196 Pg to 1-m depth. The SOC concentration in most cultivated soils is less than 5 g/kg compared with 15 to 20 g/kg in uncultivated soils. Low SOC concentration is attributed to plowing, removal of crop residue and other biosolids, and mining of soil fertility. Accelerated soil erosion by water leads to emission of 6 Tg C/y. Important strategies of soil C sequestration include restoration of degraded soils, and adoption of recommended management practices (RMPs) of agricultural and forestry soils. Potential of soil C sequestration in India is estimated at 7 to 10 Tg C/y for restoration of degraded soils and ecosystems, 5 to 7 Tg C/y for erosion control, 6 to 7 Tg C/y for adoption of RMPs on agricultural soils, and 22 to 26 Tg C/y for secondary carbonates. Thus, total potential of soil C sequestration is 39 to 49 (44± 5) Tg C/y.

Details at https://link.springer.com/article/10.1023/B:CLIM.0000038202.46720.37

Legal measures - who is worried in India for escalating emissions or lowered sequestration capabilities with accelerated deforestation?

17. What are the legal loopholes? What measures are needed to plug these legal loopholes?

Unplanned developmental activities and lack of appropriate regulary mechanism to implement our legislations coupled with the rampant corruption and greed of the current breed of decision makers (colonial mind-set)

18. In the recently concluded UNCCD COP 14 India has pledged to restore 26 million hectares of degraded lands to mitigate emissions. Please spell out the ecological measures to achieve this?

The role of native species in carbon capture or retention of water is hardly understood by the decision makers. Afforestation with native species would be an answer to climate change and also will help in ensuring adequate water to all

19. How can wetlands play a role in sequestering soil carbon? Your message to the common man…

Algae in wetlands have a high growth rate and shorter cycling time, which aid in capturing or sequestering carbon dioxide at higher rate. Furthermore, their soils are largely anaerobic so carbon that gets incorporated into the soil decomposes very slowly and can persist for hundreds or even thousands of years. Wetlands are apt mechanism to decarbonise our environment through carbon storage.

20. What are the factors threatening wetlands in South Asia?

Unplanned urbanisation, reclamation of wetlands for other land uses (agriculture), sustained inflow of untreated domestic sewage and industrial effluents, dumping of solid waste, removal of drains connecting wetlands (interconnectivities), encroachment of floodplains (buffer zones), lake beds, etc., changes in the climate (altering hydrologic regime and carbon dynamics)

21. What is the remedy/ solution? Please elucidate legal measures necessary for restoration of wetlands for restoring land degradation.

Need to enhance environmental literacy as the enhanced awareness among public might help in protecting vital ecosystems for posterity.

22. What can common man do to restore wetlands?

The greatest contribution common man can do is – having sense of belonging of his/her village, town / nation. Lack of sense of belonging (due to poor environmental literacy) is leading to the abuse of our natural resources. Next generation would be grateful to the current generation, if we ensure sustenance of natural resources (sustenance of water, etc.) by not abusing vital ecosystems. Nation needs to develop but not at the cost of sustenance of natural resources and health of the youth. Abusing water bodies with contaminants (due to pollutants) has enhanced the chronic diseases such as cancer, renal (kidney) failures, etc. due to the presence of heavy metals in the human food chain (fish, vegetable, milk, …). Healthy youth are an asset of the nation. But depriving the health in the youth will cost the nation. We need to wake up.

Links:

http://www.fao.org/soils-portal/soil-management/soil-carbon-sequestration/en/

https://get.pdf-maker.com/?pid=56246&clickid=AE2DB750-D6AD-11E9-B930-F328D45F04C4&subid=23005&pgs=1

http://www.fao.org/fileadmin/templates/solaw/files/thematic_reports/TR_04b_web.pdf

https://en.wikipedia.org/wiki/Mycorrhizal_fungi_and_soil_carbon_storage

https://download.howtosimplified.com/index.jhtml?partner=%5eAW6%5expt414&s1=23005&s2=7B68CBF0-D7AF-11E9-B402-A1E26BEF28E9

https://nidm.gov.in/pdf/guidelines/new/landslidessnowavalanches.pdf

https://agricultureandfood.dk/climate-neutral-2050/climate-neutral-2050

UNCCD Executive Secretary meets with Ambassador of Turkmenistan

Bonn, Germany – The Ambassador of Turkmenistan to the Federal Republic of Germany Mr. Toily Atayev and the First Consulate Mr. Murad Ozbekbayev visited the UNCCD secretariat last week to meet with the UNCCD Executive Secretary Mr. Ibrahim Thiaw and the UNCCD staff.

During the meeting, the Ambassador presented the continued efforts of Turkmenistan in afforestation and preservation of desert ecosystems – the clearing of wooded areas is prevented by improving gas supply to the remote areas of the country. Turkmenistan also plays an active role in the regional ecological initiatives – since 2018, the country has been chairing the International Fund on Aral Sea Rescue and hosted the Summit of the Heads of Central Asian countries to mobilize efforts that mitigate the results of the Aral Sea ecological catastrophe. In this context, Mr. Atayev specifically underlined the importance of the UNCCD Drought Initiative as well as sand and dust storms mitigation both at national and regional levels.

The Ambassador and the Executive Secretary also exchanged views on the opportunities that drylands represent for biophysical rehabilitation and economic development. The representatives of Turkmenistan confirmed that the country is interested in expanding its collaboration with UNCCD on these issues.

The Executive Secretary accepted the invitation to visit Turkmenistan next year and encouraged the government of Turkmenistan to actively participate in the negotiations of the upcoming UNCCD COP14 in India.