Hill Slope Research Articles

Investigation on spontaneous fires regions in coal gangue hills using UAV thermal infrared images

ABSTRACT The spontaneous combustion of coal gangue hills is accompanied by the release of toxic gases and the infiltration of metal elements, posing a serious threat to the global ecological environment. The current temperature monitoring methods for coal gangue hills have certain limitations, hence advanced and timely temperature monitoring is crucial for the management of coal gangue hills. This paper takes Guojiahe coal gangue hill as an example, thousands of visible light and thermal infrared images are obtained by using an unmanned aerial vehicle, and the 3-D model of the surface temperature of the gangue hill is established with Gaussian kernel technique and Random Sampling Consensus Method (RANSAC). Furthermore, the high-temperature zone in the gangue hill is measured by handheld thermocouples. The results indicate that high-temperature areas are distributed in a circular pattern and mostly concentrated on the slope surface and the boundary line between the slope and the bench. The thermal images can reflect the temperature inside the gangue hill by comparing the results of thermocouple temperature measurement and UAV detection. Further, it is analyzed that the air leakage cracks formed on the slope of the gangue hill provide a channel for the combination of coal gangue and oxygen, accelerating the heat accumulation, and the three-field coupling mechanism of coal gangue spontaneous combustion is proposed. This study can provide technical and methodological support for the prevention and control of spontaneous combustion in coal gangue hills.

Vetiver [Chrysopogon zizanioides (L.) Roberty]: An Aromatic Root Crop for Soil and Water Conservation

Khus grass or vetiver (Chrysopogon zizanioides (L.) Roberty) is a hardy perennial aromatic grass with long enormous tufted fibrous root system. Commercially, dry roots are used for extraction of essential oil that acts as a fixative in perfumery industry worldwide. Besides, vetiver roots are used in medicinal and pharmaceutical industries to treat rheumatism, arthritis, gouty joints, paralysis and indigestion. Roots and root oil have strong anti-oxidant, stimulant, carminative and cooling properties and used in Ayurvedic medicines. Traditionally, vetiver plants are being used to cultivate across hill slopes, waterways and wastelands to reduce runoff and soil conservation. During 1990’s World bank was promoting use of vetiver grass as contour vegetative barrier in upland farming systems of Asian and African countries. Further, recent studies report the use of vetiver in phytoremediation, reclamation of mined lands and soil and water detoxification in addition to carbon sequestration. Due to introduction of modern cultivation practices, traditional soil conservation practices are being vanished gradually over a period of time. In this regard, an attempt has been made to review the scientific evidence for use of vetiver grass as a soil and water conservation measure along with phytoremediation.

Impact of Summer Air Temperature on Water and Solute Transport on a Permafrost‐Affected Slope in West Greenland

AbstractIn Arctic landscapes, the active layer forms a near‐surface aquifer on top of the permafrost where water and nutrients are available for plants or subject to downslope transport. Warmer summer air temperatures can increase the thickness of the active layer and alter the partitioning of water into evapotranspiration and discharge by increasing the potential evapotranspiration, the depth to the water table, and changing the flow paths but the interacting processes are poorly understood. In this study, a numerical model for surface‐ and subsurface cryo‐hydrology is calibrated based on field observations from a discontinue permafrost area in West Greenland considered sensitive to future climate changes. The validated model is used to simulate the effect of three summers with contrasting temperature regimes to quantify the variations in the active layer thickness, the resulting changes in the water balance, and the implications on solute transport. We find that an increase of summer air temperature by1.6°C, under similar precipitation can increase the active layer thickness by 0.25 m, increase evapotranspiration by 5%, and reduce the total discharge compared to a colder summer by 9%. Differences in soil moisture and evapotranspiration between upslope and downslope were amplified in a warm summer. These hydrological differences impact solute transport which is 1.6 times faster in a cold summer. Surprisingly, we note that future warmer summer with increase in permafrost thaw may not necessary lead to an increase in discharge along a hill slope with underlying permafrost.

Behavior of RC Buildings Located on Hill Slopes under Earthquake Shaking

Behavior of RC Buildings Located on Hill Slopes under Earthquake Shaking

Geophysical characterization of the bedrock and regolith in the Pranmati basin critical zone, Uttarakhand Himalaya

The young active Himalayan mountain is characterized by steep slope and dissected topography in overall compressive tectonic setting. The mountain belt has primarily coarse textured soil with poor water holding capacity and is highly prone to erosion. The erosion not only affects many ecosystems located at downstream but also has detrimental effects on the critical zone (CZ). In the present study, we have carried out DC electrical resistivity study in the Pranmati catchment of the Alaknanda basin, a Himalayan critical zone in the Lesser Himalaya, to understand the pattern of soil erosion, transportation and deposition by characterizing the bedrock architecture and hence regolith thickness. A total of 6 electrical resistivity tomogram (ERT) profiles were laid at two locations in the catchment, one in a plain grassland and another at a crop field located on a hill slope of >25o. The study area in the Baijnath klippe, consists of quartz-biotite gneisses with layers of quartz mica-schist enclosed by thrust faults. Electrical resistivity sections of the downslope grassland site show a sharp resistivity contrast between the southwest and northeast transects suggesting south-eastern increase in dip of the bedrock, oblique to the north-east facing surface topography and a thick regolith (> 10 m). The resistivity sections of the site located on the hillslope yield a very thin layer of regolith (< 2 m) indicating significant soil erosion and high weathering of the bedrock. We propose that the water–rock interaction within the porous regolith facilitated by subsurface water circulation might be a potential source for the thick regolith. The observations substantiate existing hypotheses for the evolution and development of deep critical zones. From the results, it has been hypothesized that the bedrock architecture and water channel paths within the CZ together control the regolith thickness.

Subterranean clover growth responded to grass suppression, phosphorus and molybdenum fertilisers in a summer dry hill environment

Pastures on the north-facing slopes of the Port Hills, Canterbury, are summer-dry, grass dominant, and have low soil phosphorous and sulphur fertility. The aim of this experiment was to improve the establishment of oversown subterranean (sub) clover by the addition of fertilizer and grass-supressing herbicide. Treatments were a factorial combination of phosphorous (0 or 60 kg P/ha, -P or +P), sulphur (0 or 50 kg S/ha, -S or +S), and molybdenum (0 or 0.06 kg Mo/ha, -Mo or +Mo), with or without autumn herbicide (plus or minus, +H or -H). Fertilisers were applied in 2021, with P and S reapplied in 2023, and herbicide applied in 2022 and 2023. Pasture yields were measured annually from 2021 to 2023. Measurements in 2021 found no fertiliser effect on total pasture yield of 3650±83 kg DM/ha that included 770±43 kg of sub clover. In 2022, P addition increased total pasture yield from 2900 to 3270 kg DM/ha. Herbicide application doubled the sub clover yield from 310 to 645 kg DM/ha and reduced grass from 1650 to 1410 kg DM/ha. In 2023, the herbicide application did not affect the total accumulated pasture yield (10180±160 kg DM/ha) but increased sub clover content from 10 to 25% and reduced the grasses from 63 to 47%, with about 4% white clover. Where herbicide was applied without fertiliser (+H), total clover yield increased from 1460 to 2930 kg DM/ha. The application of P and Mo, (i.e., +H+P+Mo treatment) increased it further to 4010 kg DM/ha. There was no yield response to +S or +Mo unless added with P. Applying herbicide or phosphorous increased total metabolisable energy from 38.5 to 42.6 GJ ME/ha and crude protein from 500 to 595 kg/ha in pastures sampled in November 2023. The treatment combination providing the highest feed quality values was +H+P+Mo. These results suggest that to optimise sub clover content of pastures on the Port Hills competing grasses must be controlled initially, followed by P fertiliser if soil tests indicate it is required along with molybdenum.

Elucidating the link between binding statistics and Shannon information in biological networks.

The response of a biological network to ligand binding is of crucial importance for regulatory control in various cellular biophysical processes that is achieved with information transmission through the different ligand-bound states of such networks. In this work, we address a vital issue regarding the link between the information content of such network states and the experimentally measurable binding statistics. Several fundamental networks of cooperative ligand binding, with the bound states being adjacent in time only and in both space and time, are considered for this purpose using the chemical master equation approach. To express the binding characteristics in the language of information, a quantity denoted as differential information index is employed based on the Shannon information. The index, determined for the whole network, follows a linear relationship with (logarithmic) ligand concentration with a slope equal to the size of the system. On the other hand, the variation of Shannon information associated with the individual network states and the logarithmic sensitivity of its slope are shown to have generic forms related to the average binding number and variance, respectively, the latter yielding the Hill slope, the phenomenological measure of cooperativity. Furthermore, the variation of Shannon information entropy, the average of Shannon information, is also shown to be related to the average binding.

Seismic Performance of Reinforced Concrete Frames on Sloped Ground Using Non-Linear Static Pushover Analysis

Nepal, renowned for its majestic Himalayan Ranges, is also highly vulnerable to seismic activity. Buildings on hill slopes often endure more significant damage during earthquakes than those on flat terrain. Traditional seismic analyses of buildings typically employ linear-static and dynamic methods, which might not fully represent the building's behavior under actual seismic conditions. This research addresses this gap by assessing the seismic performance of buildings on hill slopes using non-linear static analysis techniques. Specifically, the study evaluates the seismic response of 5-story buildings with stepback and stepback-setback configurations on slopes of 15°, 30°, and 45°. This evaluation is conducted through non-linear static analysis, also known as Pushover Analysis, using ETABSv20 software. Key performance metrics analyzed include the building's period, topstorey displacement, and base shear. The findings reveal that buildings with stepbacksetback configurations demonstrate superior seismic performance on the sloping ground compared to those with stepback configurations. This study underscores the importance of employing non-linear analysis methods to better understand and improve seismic resilience in hilly terrains.

Abstract P426: Reduced Nfatc1 Expression Results in Enhanced Pressure Natriuresis and Resistance to Salt-Sensitive Hypertension

Background: Nuclear factor of activated T cells-cytoplasmic 1 (NFATc1) has recently been shown to have a non-canonical role in chronic kidney disease in humans by a trans-ethnic meta-analysis of genome-wide associate studies (GWAS). Follow-up studies in a salt-sensitive mouse model showed that Nfatc1 mRNA expression was suppressed in the kidneys when animals were fed a high-salt diet. Here, we further explore the link between NFATc1 and salt-sensitive (SS) hypertension. Methods: Adult male wild-type (WT) and heterozygous Nfatc1 knockout (Het) mice (2-5 months of age) on the SS 129S6 background were started on standard chow (0.8% NaCl, NSD) and then switched to a high-salt diet (6% NaCl, HSD). Systolic blood pressure (SBP) was measured by either tail cuff manometry with at least 2 weeks of training or implantable radiotelemetry transmitters with at least 2 weeks of post-surgical recovery. Immediately before and for 2-3 days after the change in diet, 24 h urine was collected using metabolic cages, and urinary sodium was measured by flame photometry. Sigmoid pressure-natriuresis curves were generated and the Hill slope was compared between genotypes. Results: WT mice showed a significant increase in SBP between NSD and after 3 weeks on HSD (127.8±9.9 vs 143.4±8.9, p = 0.0089, n = 9). In contrast, Het mice had no change in SBP (125.8±8.7 mmHg vs. 125.7±10.6 mmHg, p = 1.0, n = 9). During the initial switch to the HSD, SBP was not significantly different between WT and Het mice (133.2±2.9 vs. 134.4±3.0, p = 0.45, n = 7/group). However, WT mice had a shallower pressure-natriuresis curve (Hill slope of 0.58 vs. 0.93, 7 mice/group, 25/26 data points). Conclusion: Our data illustrates that decreasing Nfatc1 expression in a mouse model is protective against SS hypertension. While acute increases in SBP in response to HSD remained in Het mice, sodium excretion was increased and SBP remained unchanged after 3 weeks, indicating that NFATc1 has the potential to be a therapeutic target against SS hypertension.

Effect of hills on wind turbine flow and power efficiency: A large-eddy simulation study

This study investigates the influence of topography on wind turbine flow and power efficiency. Specifically, a standalone wind turbine is positioned at the top of idealized two-dimensional hills, and the effects of hill geometry and turbine position are systematically investigated. Various parameters are studied, including hill slope, distance between the leeward side of the hill and the turbine, turbine hub height, and hill size. Overall, it is observed that the turbine wake is consistently stronger in the hill cases compared to the flat case. This is attributed to two characteristics of hill flows: (1) the negative streamwise velocity gradients on the leeward side of the hills and (2) the reduced turbulence above the hilltops and hill wake regions. In addition, it is observed that the turbine induction factor is consistently increased in the hill cases compared to the flat case, while the turbine power and thrust coefficients are reduced. In practice, this means that turbines on the hills produce less power output than those on flat terrain for an equivalent wind potential, with the potential decrease in power output reaching more than 20% for certain cases. Altogether, the results offer new insights into the effect of topography on turbine power efficiency. In addition, the study identifies clear relationships between the turbine power coefficient, the induction factor, the overall maximum deficit, and the base flow pressure gradient. These relationships could potentially be used to predict the change in power efficiency based on the wake flow or the base flow. Overall, the results show a clear connection between the turbine power efficiency and the turbine wake development.

Spectral deconvolution approach for Beryllium-7 detection: Evaluating soil redistribution with NaI(Tl) detectors

Beryllium-7 is a cosmogenic radionuclide produced in the upper atmosphere through the spallation of cosmic rays and falls to Earth mainly by wet deposition. Given its short half-life (53 days) and strong adsorption to the clay present in the soil, 7Be inventory can be evaluated to obtain information about soil redistribution over periods of up to 6 months. By performing these measurements, one can infer the efficiency of soil management and conservation procedures. The isotope presence is measured using gamma-ray spectrometry to detect its decay emission, specifically a photon with an energy of 477.6 keV. Since other isotopes found in soil emit photons with similar energies, it is common to use High-Purity Germanium (HPGe) detectors due to their high energy resolution. However, these detectors are expensive and require cryogenic cooling during operation. An alternative is the Thallium-Activated Sodium Iodide (NaI(Tl)) detector, which is less costly and does not require cryogenic cooling, but has poorer resolution and cannot separate the emissions from 228Ac (463.0 keV), 7Be, and 208Tl (510.7 keV). This work aims to apply spectral deconvolution to quantify 7Be in soil samples collected from an agricultural mega-parcel situated on a hill slope and evaluate the soil redistribution experienced within. The activities of the interfering isotopes were quantified using other emissions, and the results were used to calculate the corresponding area in the desired region of the spectra. From this, 7Be activities were calculated and compared with the HPGe results to validate the deconvolution technique. The calculated activities for the three radioisotopes showed similar correspondence between the two detectors, indicating that the applied method is adequate for evaluating soil redistribution at lower costs. The calculated net soil deposition was 36.4 ± 6.4 kgm−2 for the NaI(Tl) detector and 26.4 ± 7.9 kgm−2 for the HPGe detector during the evaluated period. Furthermore, these results suggest that a similar approach can be applied to quantify other isotopes using NaI(Tl) detectors as an alternative to HPGe detectors.

Impact of building topologies on hill slope stability in Aizawl city

In hilly regions like Aizawl city, wherein houses are mostly built on slopes, the layout of building plays a crucial role in slope stability. Building failures in Aizawl often results from a) non-engineered alterations of slopes b) faulty foundation construction without soil investigation or design. Many residents build and reside on slopes without considering the soil characteristics. To address this, a study was conducted to examine the impact of two common building types - step-back buildings and step-back setback buildings on slope stability in Aizawl. Fifty different sites with varying slope geometries were analysed using Limit Equilibrium Method (LEM), considering soil parameters like cohesion, internal friction angle, unit weight, and slope geometry. The study evaluated slope stability under conditions such as free slope, slope with building loads under static and seismic conditions. The study found that sites with lower slope angles generally demonstrated greater stability, but there were cases where steeper slopes showed better stability due to superior shear strength values. Sites with higher cohesion values exhibited better stability in free slope analysis, while those with higher internal friction angles showed better stability under building loads of both static and seismic condition. To validate the above findings, a sensitivity analysis along with a comparative analysis between step-back and step-back setback building types were conducted. The results indicated that step-back setback buildings offered better stability compared to step-back buildings alone. This suggests that implementing step-back setback buildings could significantly improve slope stability in cities like Aizawl.

Landscape Characters of Kampung Ciomas for Eco-edutourism

Abstract Kampung Ciomas has a natural physical environment. This condition has the potential to become a tourist destination with an eco-edutourism theme. This research aims to analyze the landscape character of Kampung Ciomas for eco-edutourism. Analysis was carried out using quantitative descriptive and qualitative descriptive methods. The research stages carried out were: 1) analyzing land cover, 2) analyzing slope, and 3) analyzing landscape character. The results of the analysis showed that there were 28 types of landscape character which were dominated by green open spaces on hill slopes. The landscape character protection required is the protection of green open space on sloping hills and moderate hills. Modifications of the landscape character required include the removal of several elements that are not in harmony with several buildings and ponds on sloping hillsides, stalls on sloping hills, emphasizing natural forms planned on green open space on medium hills, changes in natural form are planned for green open space on flat, undulating slopes and sloping hills, intensification is carried out on green open space on sloping hills and medium hills, intensive visual quality improvements are intensively planned for green open space on flat, undulating slopes, sloping hills and moderate hills, circulation paths on undulating slopes and sloping hills, BTS (Base Transceiver Station), WWTP (Waste Water Treatment Plant), parking lots on sloping hillsides, cemeteries and mosque on sloping hillsides. The impact of this research is providing alternative tourism in Bogor accordance environmental conditions and environmental utilization through conservation and education efforts.

Large dump critical zone of interest identification and slope failure prediction using realistic 3D numerical modelling

Dump failure is one of the most catastrophic hazards in the opencast mining industry and involves sudden and violent failures. Therefore, susceptible region identification is essential for slope failure mitigation in the large dump. This study proposed a sustainable approach for large dump critical zone of interest (CZI) identification, stability monitoring and slope failure prediction. UAV close-range photogrammetry survey and structure-from-motion (SfM) approach were used for the dump realistic 3D model reconstruction. 3D numerical modelling was employed for dump stability analysis. In this investigation, the dump critical zone, slope factor of safety (FOS), displacement and slope failure prediction were analysed using the 3D numerical modelling. The results indicate that maximum displacement was found in the critical zone I. However, the dump was stable under static conditions. Dump critical slope failure time is predicted using the inverse velocity method. The results of this investigation are reliable and establish the scope of UAV photogrammetry for realistic 3D modelling. In addition, the slope stability state and failure model were consistent with field observations. The proposed approach can be used for the mine, hill, and roadcut slopes. UAV technology and 3D modelling approaches have substantially reduced data collection time and expense.

Assessment of Production and Soil Conservation Potential of Aromatic Grasses Grown Under Shifting Cultivated Degraded Hill Slopes of Eastern Ghats, India

Assessment of Production and Soil Conservation Potential of Aromatic Grasses Grown Under Shifting Cultivated Degraded Hill Slopes of Eastern Ghats, India

Comparative Study of Seismic Analysis of Reinforced Concrete Framed Buildings on Hill Slopes

Comparative Study of Seismic Analysis of Reinforced Concrete Framed Buildings on Hill Slopes

Conceptual basis of architectural and urban planning heritage development in ethnic regions of Ukraine

The article describes the results of the philosophical and methodological analysis of the definitions - "formation", "concept" and "network" in the context of the preservation of architectural and urban heritage in ethnic regions of Ukraine. The relationship between these definitions and modern ideas about sustainable development and self-organization is revealed by their postmodern interpretation and architectural-sociological orientation. On this basis, two macrocosmic principles - the tectonicity of the formation of cultural focuses and the cyclicity nature of the sustainable development of ethnic regions, and two microcosmic principles - the architectonicity self-organization of the areas of these focuses’ and the ornamentality of their network is theoretically substantiated. These principles form the philosophical foundations of the formation of regional networks of historical centers of architectural and urban heritage on the territory of Ukraine. The principle of cyclicity reflects the recurrence of periodic changes in natural phenomena and stages of sustainable development of settlements and communities. The essence of the principle of tectonicity consists in the non-accidental placement of the overwhelming majority of focuses’ of architectural and urban heritage, which are provincial cities and towns, outside the zones of tectonic rupture dislocations and geopathogenic zones. The principle of architectonicity, which connects the natural and artificial environment, regulates the location of individual focuses’ and areas outside of fully urbanized territories, between highways and railways of national and international importance. The natural component of the architectonicity principle is rooted in the desire of a large part of historical provincial cities, towns, and villages to be located in a functionally and aesthetically attractive landscape environment - on the coasts of seas, lakes, and rivers, on the tops and slopes of hills, against the background of forest areas, etc. The principle of ornamentality integrates macrocosmic cyclicity and tectonicity with microcosmic architectonicity. It has a multi-layered structure, contains potentials, and becomes a regulator of the formation and sustainable development of the investigated network at all levels of its architectonical structure.

Assessment of stability and operability of skidder on slopes of thawing soil mass during its interaction with a wheeled forest machine

In the Russian Federation, a significant part of the forest fund is located on permafrost. Permafrost forests play a global ecological role by de-populating large amounts of carbon. However, when a forest reaches the age of obsolescence, this carbon is released into the atmosphere when the plantation decays. Therefore, from the ecological point of view, permafrost forests should be cut down when they reach the age of ripeness, in compliance with the requirements for their restoration. Many of the above-mentioned regions have large reserves of mature and overmature production forests, and a significant part of these reserves are located in hard-to-reach places, not only in relation to the development of the road network, but also by terrain relief. Currently, the vast majority of timber harvesting in Russia is done with modern machinery complexes, mainly including wheeled forest machines of different layout and purpose (harvesters, forwarders, skidders, etc.). With the help of special technical solutions, such as winches integrated into the transmission, or self-propelled winches (T-winch, ROB, Winch Assist), these machines can be successfully operated even on fairly steep slopes. The problem of negative effect of wheeled forest machines and skidding systems based on them not only stays actual, but also becomes even more urgent, as the ecosystems of mountain forests, forests on the slopes of hills, etc. are the most vulnerable and exposed to water and wind erosion. This article presents a mathematical model for reliable forecasting of rut depth and stability of a hairpin section during dynamic interaction of a forest machine with the soil on slopes, taking into account geometric parameters of the slope, the laws of the oscillating process of a forest machine with given values of speed and amortization characteristics of wheel-pair elements, the profile of the hairpin section and physical and mechanical properties of the soil in its boundaries, the weight of forest machines and the pressure in tires of wheel-pairs.

Exploring Catalase Activity as A Biological Indicator in Degraded Soils

This study examines the relationship between catalase activity in degraded soils and soil properties, and addresses its potential as an indicator of soil health and productivity. Catalase, a key enzyme reflecting microbial activity and soil aeration, has been analyzed in 30 soil samples collected from the disturbed surface layer (0-15 cm depth) of erosion-prone areas characterized by rubble accumulation on hill slopes and soil compaction in foot slopes. The soil in the study area is classified as Typic Xerortent. Catalase enzyme activity in the soil samples varied between 10.4 and 48 µl O2 g-1 dry soil. In addition to catalase, the physicochemical properties of the soil were also assessed, including pH, electrical conductivity, organic matter content, and texture. Nutrient contents, including nitrogen (0.046-0.239 g N 100 g-1), phosphorus (1.77-20.05 µg P g-1), and potassium (0.01-3.31 meq K 100 g-1), were also measured. A positive correlation was observed between catalase activity and potassium and phosphorus levels, but the relationship with nitrogen was statistically insignificant. These findings suggest that catalase activity can serve as a biological indicator for the early detection of degradation in soils at risk of erosion. The study provides valuable insights into the impact of erosion on soil biochemistry and highlights the role of catalase in assessing soil health and guiding sustainable land management practices.

Agricultural land suitability analysis in Manipur, India using GIS and AHP

This article aims to identify potential sites for agricultural use in the state of Manipur of north east India by employing the analytic hierarchy process in a geographic information system environment in conjunction with the use of remote sensing and soil data. Within the analytic hierarchy process, each terrain variable underwent a pairwise comparison and criteria weights were assigned according to their relative importance. Eight variables were selected and used in land suitability analysis for agriculture. It was found that Manipur had 57% (12,660 km2) of its total geographical area suitable for agriculture. However, 8126 km2 (37%) and 1374 km2 (6%) of the total geographical area was currently and permanently unsuitable land respectively. The distribution of suitable land varied greatly, with highly, moderately and marginally suitable land covering only 8%, 16% and 33% respectively of the total geographical area. The highly suitable agricultural land is predominantly concentrated in the Imphal valley (70%), though 90% of moderately suitable and 96% of marginally suitable land also exist in the hills. The hilly areas constitute 96% and 97% respectively of currently unsuitable and permanently unsuitable land in the state. Suitable land comprises of land with low to medium altitude, gentle to moderate slopes, soil of fine or acceptable quality, and with minimal flood risk. Unsuitable lands tend to be diametrically opposite to these attributes with steep hill slopes. The nature of distribution of land suitability types influences the agricultural pattern in Manipur. Agriculture in the hill areas comprises mainly of shifting cultivation on hill slopes, whereas in the valley region it is irrigated and permanent. This analysis of Manipur has a wider applicability since the shifting cultivation-irrigated agriculture combination is similar to that which exists across much of the highlands of South East Asia.