Vegetation and altitudinal zonation in relation to the impact of grazing in the steppe lands of the Hindu Kush Range (N-Pakistan)

A cenotic diversity of the Berd River and its tributaries is ascertained as 23 associations, 2 subassociations, 2 variants and 4 communities referred to 3 vegetation classes of the Braun-Blanquet approach: Phragmito-Magnocaricetea (15 associations, 2 subassociations, 2 variants), Potametea (7 associations and 4 communities), Isoёto-Nanojuncetea (1 association). Cenotic structure and spatial allocation of stream vegetation of various parts of the Berd River are determined mainly by a ratio of the erosion-accumulation processes in the river bed and trophic status of waters, with the impact of altitudinal zonation beeing less significant. The cenotic diversity increases in the range «uppermeanlower flow». Two new associations of class Potametea Klika in Klika et Novak 1941, order Potametalia W. Koch 1926 are described: Scirpo lacustris—Nupharetum luteae within the alliance Nymphaeion albae Oberd. 1957, and Fontinali antipyreticae—Scirpetum lacustris within the Batrachion fluitantis Neuhäusl 1959. Some specifications to the interpretation of the order Oenanthetalia aquaticae Hejný in Kopecký et Hejný 1965 are given.

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Impacts of Aerosol Loading in the Hindu Kush Himalayan Region Based on MERRA-2 Reanalysis Data

Atmosphere ◽

10.3390/atmos12101290 ◽

2021 ◽

Vol 12 (10) ◽

pp. 1290

Author(s):

Shantikumar S. Ningombam ◽

Umesh Chandra Dumka ◽

Sivasamy Kalamani Mugil ◽

Jagdish Chandra Kuniyal ◽

Rakesh K. Hooda ◽

...

Keyword(s):

Anthropogenic Activities ◽

Statistical Significance ◽

Regional Scale ◽

Correlation Coefficients ◽

Reanalysis Data ◽

Climatic Conditions ◽

Energy Demands ◽

Hindu Kush ◽

Student’S T ◽

The Impact

The impacts of climate change have severely affected geosphere, biosphere and cryosphere ecosystems in the Hindu Kush Himalayan (HKH) region. The impact has been accelerating further during the last few decades due to rapid increase in anthropogenic activities such as modernization, industrialization and urbanization, along with energy demands. In view of this, the present work attempts to examine aerosol optical depth (AOD) over the HKH region using the long-term homogeneous MERRA-2 reanalysis data from January, 1980 to December, 2020. The AOD trends are examined statistically with student’s t-test (t). Due to a vast landmass, fragile topography and harsh climatic conditions, we categorized the HKH region into three sub-regions, namely, the northwestern and Karakoram (HKH1), the Central (HKH2) and the southeastern Himalaya and Tibetan Plateau (HKH3). Among the sub-regions, the significant enhancement of AOD is observed at several potential sites in the HKH2 region, namely, Pokhara, Nainital, Shimla and Dehradun by 55.75 × 10−4 ± 3.76 × 10−4, 53.15 × 10−4 ± 3.94 × 10−4, 51.53 × 10−4 ± 4.99 × 10−4 and 39.16 × 10−4 ± 4.08 × 10−4 AOD year−1 (550 nm), respectively, with correlation coefficients (Rs) of 0.86 to 0.93. However, at a sub-regional scale, HKH1, HKH2 and HKH3 exhibit 23.33 × 10−4 ± 2.28 × 10−4, 32.20 × 10−4 ± 2.58 × 10−4 and 9.48 × 10−4 ± 1.21 × 10−4 AOD year−1, respectively. The estimated trends are statistically significant (t > 7.0) with R from 0.81 to 0.91. Seasonally, the present study also shows strong positive AOD trends at several potential sites located in the HKH2 region, such as Pokhara, Nainital, Shimla and Dehradun, with minimum 19.81 × 10−4 ± 3.38 × 10−4 to maximum 72.95 × 10−4 ± 4.89 × 10−4 AOD year−1 with statistical significance. In addition, there are also increasing AOD trends at all the high-altitude background sites in all seasons.

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Climate change implications for the glaciers of the Hindu-Kush, Karakoram and Himalayan region

The Cryosphere Discussions ◽

10.5194/tcd-7-3717-2013 ◽

2013 ◽

Vol 7 (4) ◽

pp. 3717-3748 ◽

Cited By ~ 1

Author(s):

A. J. Wiltshire

Keyword(s):

Climate Change ◽

Water Resources ◽

Mass Balance ◽

21St Century ◽

Glacier Mass Balance ◽

Climate Modelling ◽

Degree Days ◽

Hindu Kush ◽

The Impact ◽

Accumulated Degree Days

Abstract. The Hindu-Kush, Karakoram Himalaya (HKKH) region has a negative average glacial mass balance despite anomalous possible gains in the Karakoram. However, changes in climate may influence the mass balance across the HKKH. We use high resolution climate modelling to analyse the implications of unmitigated climate change on precipitation, snowfall, air temperature and accumulated degree days for the Hindu Kush, Karakoram, Jammu-Kashmir, Himachal Pradesh and West Nepal regions, and East Nepal and Bhutan. In our analysis we focus on the climate drivers of change rather than the glaciological response. We find a complex regional response to climate change, with possible increases in snowfall over the western HKKH and decreases in the east. Accumulated degree days are less spatially variable than precipitation and show an increase in potential ablation in all regions. Overall, the eastern Himalayan glaciers are expected to be most sensitive to climate change due to the decreases in snowfall and increased ablation associated with warming. The eastern glaciers are therefore projected to decline over the 21st century despite increasing precipitation. The western glaciers are expected to decline at a slower rate over the 21st century as a response to unmitigated climate compared to the glaciers of the east. Importantly, the glacier response depends on important glaciological factors, such as the extent of debris cover, which may be of critical importance in moderating the response to climatic change. Decadal variability has a large effect highlighting the need for long-term observation records to fully understand the impact of climate on the glaciers of the HKKH cryosphere. Spatial variability in projected snowfall patterns are likely to be a key driver of glacier mass balance over the 21st century. Importantly, the regional trends in snowfall do not necessarily follow the trends in precipitation. A key change in the HKKH cryosphere is a switch from snowfall to rainfall in the eastern Himalaya. Although glacial mass balance is likely to be sensitive to climate change, as overall precipitation is projected to increase this may lead to an overall increase in water resources. In the west, projections suggest that glacial mass balance could respond less to climate change than those in the east. However, projection uncertainty covers a small increase to a decrease in precipitation for the western HKKH and Indus basin and as a result the water resources of the highly populated Indus region may be more vulnerable to unmitigated climate change.

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The Impact of Climate Change in Hindu Kush Himalayas: Key Sustainability Issues

Himalayan Weather and Climate and their Impact on the Environment ◽

10.1007/978-3-030-29684-1_22 ◽

2019 ◽

pp. 453-472

Author(s):

Surendra P. Singh ◽

Rajesh Thadani ◽

G. C. S. Negi ◽

Ripu Daman Singh ◽

Surabhi Gumber

Keyword(s):

Climate Change ◽

Impact Of Climate Change ◽

Hindu Kush ◽

The Impact

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Comparison of river quality indices to detect the impact of organic pollution and water abstraction in Hindu Kush-Himalayan rivers of Nepal

Journal of Wetlands Ecology ◽

10.3126/jowe.v4i0.2545 ◽

2011 ◽

Vol 4 ◽

pp. 112-127 ◽

Cited By ~ 4

Author(s):

Christian Karl Feld ◽

Marijn Tangelder ◽

Maaike Johanna Klomp ◽

Subodh Sharma

Keyword(s):

Scoring Systems ◽

Organic Pollution ◽

Benthic Invertebrate ◽

Pollution Gradient ◽

Water Abstraction ◽

Quality Classification ◽

Hindu Kush ◽

River Quality ◽

Benthic Invertebrate Communities ◽

The Impact

Several assessment methods exist for river quality classification in the Hindu Kush-Himalayan region. While rapid field bioassessment (RFB)1 applies on-site screening protocols, more sophisticated multi-habitat sampling (MHS) is employed to generate biotic scores using benthic macroinvertebates as bioindicators. This study presents the comparison of River Quality Classifications (RQC) according to i) 40 RFB records based on two slightly different RFB protocols and ii) 20 qualitative benthic macroinvertebrate samples used to calculate two different scores (average scores per taxon; ASPT). Sensory attributes, such as odour, colour, foam and epilithic algal cover, were used in addition to biological samples for RFB. All samples were taken at two river basins in Nepal, the Punyamata river (12 stations, stressor: organic pollution) and the Khimti river (8 stations, stressor: damming and water abstraction). RQCs revealed organic pollution to impact benthic invertebrate communities in the Punyamata river, while the impact of water abstraction and damming was not detectable in the Khimti basin based on the methods compared. Furthermore, a pollution gradient was clearly detectable based on 66 macroinvertebrate families and genera found in our samples.Our results confirm the applicability of RFB protocols and scoring systems to asses the impact of organic pollution in Nepalese rivers. Further research, however, will be required to adjust the protocols and taxon scores to assess also the impact of other stressors present in the region.Key words: Rapid field bioassessment; benthic macroinvertebrates; NEPBIOS; ASPT; water quality; Punyamata; Khimti DOI: 10.3126/jowe.v4i0.2545Journal of Wetlands Ecology, (2010) Vol. 4, pp 112-127

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Detecting change in Landsat time series with BFAST in the eastern Hindu Kush region

10.5194/egusphere-egu2020-19630 ◽

2020 ◽

Author(s):

Saeed Akhtar Khan ◽

Oliver Sass ◽

Cyrus Samimi

Keyword(s):

Time Series ◽

The United States ◽

Thematic Mapper ◽

United States Geological Survey ◽

Landsat 8 ◽

Surface Reflectance ◽

Data Archive ◽

Landsat Data ◽

Hindu Kush ◽

The Impact

Environmental change is a trigger of land use change and possibly for migration in the eastern Hindu Kush mountains. Vegetation along the river valleys has undergone alterations by the impact of geomorphological processes and flood dynamics, but little research has been carried out to detect and map these changes. This study aims to close research gaps by detecting change within Landsat time series for the eastern Hindu Kush region.The study area is approximately 25000 km&#178; large and located in the highlands of northern Pakistan and eastern Afghanistan. It is part of upper Indus basin and is prone to natural hazards such as floods, glacial lake outbursts and landslides.The opening of the United States Geological Survey (USGS) Landsat data archive in 2008 led to the development of several satellite image-based time series methods for change detection. Among them, Breaks For Additive Seasonal and Trend (BFAST) was developed in 2010 to detect changes in both trend and seasonal components of the time series. The BFAST tool iteratively decomposes the time series into trend, seasonal and remainder components. The changes in the trend component denote abrupt and gradual changes while changes in seasonal component represent phenological changes.&#160;&#160;In this study we use Landsat data in time series analysis to detect change by using BFAST. All available Surface reflectance derived data is accessed from the Landsat data archive of USGS (World Reference System-2, Path 151 and Row 35) for the years 1988 to 2019. Data is acquired from the corresponding scenes of Landsat 4-5 Thematic Mapper (TM), Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 8 Operational Land Imager (OLI). It is processed to Landsat Level-2 Surface Reflectance Product by USGS and therefore has already undergone geo-referencing, atmospheric correction and detection of clouds and shadow. Data have spatial and temporal resolutions of 30 m and 16 days respectively.The BFAST approach was first tested on locations with a known history of change (e.g. floods) and then scaled up to the whole study area. The magnitude and timing of the change was detected and mapped for the study area. We expect that the findings of the research will benefit future local and regional risk studies.

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Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

Symposium - International Astronomical Union ◽

10.1017/s0074180900178404 ◽

1962 ◽

Vol 14 ◽

pp. 415-418

Author(s):

K. P. Stanyukovich ◽

V. A. Bronshten

Keyword(s):

Explosive Charge ◽

The Moon ◽

Meteorite Impacts ◽

The Earth ◽

Lunar Craters ◽

The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

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The Geosciences Applied to Lunar Exploration

Symposium - International Astronomical Union ◽

10.1017/s0074180900178222 ◽

1962 ◽

Vol 14 ◽

pp. 169-257 ◽

Cited By ~ 9

Author(s):

J. Green

Keyword(s):

Lunar Surface ◽

Probable Mechanism ◽

Point Of View ◽

Lunar Exploration ◽

Geological Model ◽

Apply Geophysics ◽

Surface Features ◽

The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

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Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

International Astronomical Union Colloquium ◽

10.1017/s0252921100014718 ◽

1997 ◽

Vol 161 ◽

pp. 197-201 ◽

Cited By ~ 1

Author(s):

Duncan Steel

Keyword(s):

Probability Distributions ◽

Regions Of Interest ◽

Significant Fraction ◽

Organic Chemicals ◽

Impact Speed ◽

The Mean ◽

The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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Organic Syntheses During the Impact of a Comet with a Gaseous Planet

International Astronomical Union Colloquium ◽

10.1017/s0252921100014706 ◽

1997 ◽

Vol 161 ◽

pp. 189-195

Author(s):

Cesare Guaita ◽

Roberto Crippa ◽

Federico Manzini

Keyword(s):

Polymeric Material ◽

Molecular Form ◽

Parent Compound ◽

Blue Filter ◽

Organic Syntheses ◽

The Impact

AbstractA large amount of CO has been detected above many SL9/Jupiter impacts. This gas was never detected before the collision. So, in our opinion, CO was released from a parent compound during the collision. We identify this compound as POM (polyoxymethylene), a formaldehyde (HCHO) polymer that, when suddenly heated, reformes monomeric HCHO. At temperatures higher than 1200°K HCHO cannot exist in molecular form and the most probable result of its decomposition is the formation of CO. At lower temperatures, HCHO can react with NH3 and/or HCN to form high UV-absorbing polymeric material. In our opinion, this kind of material has also to be taken in to account to explain the complex evolution of some SL9 impacts that we observed in CCD images taken with a blue filter.

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