Landscape Processes Research Articles

Spatial extent predicts Andean epiphyte biodiversity responses to habitat loss and fragmentation across human‐modified landscapes

AbstractAimHuman‐driven landscape processes such as habitat loss and fragmentation act on biodiversity, but their effects are mediated by the spatial scale at which they are observed. We aim to analyse the scale‐of‐effects (direction and spatial extent) of landscape‐scale processes that best explain species richness and abundance across epiphyte communities.LocationNeotropics, Northern Andes, Colombia, Eastern cordillera.TaxonVascular epiphytes, Orchidaceae.MethodsWe used field data to unravel the scale‐of‐effect of three landscape processes—habitat loss (forest cover), fragmentation (number of patches) and edge effects (edge density)—on epiphyte biodiversity. Vascular epiphytes were sampled in the understorey across 141 plots within 23 Andean forests in the eastern Colombian cordillera We focused on the community‐level responses (species richness and total abundance) of the hyperdiverse vascular epiphyte communities using generalized linear mixed models to quantify the direction and the spatial extent of the scale‐of‐effects.ResultsHabitat loss and edge effects act at fine spatial extents (scale‐of‐effects = 200 m), predicting low species richness and abundance across groups. Likewise, fragmentation negatively impacts communities, but operates at larger spatial extents (scale‐of‐effects = 2000–2400 m radius). The detection of these effects is contingent upon the spatial extent and specific landscape processes involved. Models of habitat loss within a spatial extent of 800–1500 m (large confidence intervals), fragmentation below 300 m, and edge effects above 800 m show weak statistical support (marginal r2 = 0.02–0.1). Thus, the impacts of these landscape processes may be overlooked if studied at inadequate spatial extents.Main ConclusionsWe showed that habitat loss, fragmentation and edge effects all play a negative role on understorey epiphytic communities, but their detectability is scale dependant. The scale‐of‐effects can assist landscape designs that are beneficial for epiphytic communities, by preserving forest cover, and reducing fragmentation and exposure to edge effects at small scales (200–300 m). Conversely, landscape‐scale actions directed at reducing habitat loss and fragmentation function at larger spatial extents (>2000 m). Selecting a priori or inadequate spatial extents of analysis can obscure the detectability of landscape processes.

Forest fire, thinning, and flood in wildland-urban interface: UAV and lidar-based estimate of natural disaster impacts

ContextWildland-urban interface (WUI) areas are facing increased forest fire risks and extreme precipitation events due to climate change, which can lead to post-fire flood events. The city of Flagstaff in northern Arizona, USA experienced WUI forest thinning, fire, and record rainfall events, which collectively contributed to large floods and damages to the urban neighborhoods and city infrastructure.ObjectivesWe demonstrate multi-temporal, high resolution image applications from an unoccupied aerial vehicle (UAV) and terrestrial lidar in estimating landscape disturbance impacts within the WUI. Changes in forest vegetation and bare ground cover in WUIs are particularly challenging to estimate with coarse-resolution satellite images due to fine-scale landscape processes and changes that often result in mixed pixels.MethodsUsing Sentinel-2 satellite images, we document forest fire impacts and burn severity. Using 2016 and 2021 UAV multispectral images and Structure-from-Motion data, we estimate post-thinning changes in forest canopy cover, patch sizes, canopy height distribution, and bare ground cover. Using repeat lidar data within a smaller area of the watershed, we quantify geomorphic effects in the WUI associated with the fire and subsequent flooding.ResultsWe document that thinning significantly reduced forest canopy cover, patch size, tree density, and mean canopy height resulting in substantially reduced active crown fire risks in the future. However, the thinning equipment ignited a forest fire, which burned the WUI at varying severity at the top of the watershed that drains into the city. Moderate-high severity burns occurred within 3 km of downtown Flagstaff threatening the WUI neighborhoods and the city. The upstream burned area then experienced 100-year and 200–500-year rainfall events, which resulted in large runoff-driven floods and sedimentation in the city.ConclusionWe demonstrate that UAV high resolution images and photogrammetry combined with terrestrial lidar data provide detailed and accurate estimates of forest thinning and post-fire flood impacts, which could not be estimated from coarser-resolution satellite images. Communities around the world may need to prepare their WUIs for catastrophic fires and increase capacity to manage sediment-laden stormwater since both fires and extreme weather events are projected to increase.

UAV-mounted thermal camera and its analysis on urban surface textures

Temperature increase, especially global warming, can be observed depending on various factors which led to several severe environmental problems. Urban areas are the most effected places by this temperature increase. Urban heat concentration, the so-called heat island effect, is high in structural areas. This situation causes human life to be adversely affected. Therefore, constant measurement and analyses are required to assess outdoor thermal comfort and thermal stress in urban areas. Today, unmanned aerial vehicle (UAV) systems are used as a rapid data production technique in Earth observation activities. Thermal cameras integrated into UAV systems can monitor the temperature values in urban areas precisely and constantly. This study focuses on the potential application of a UAV-mounted thermal camera system at a local scale due to its rapid response to surface temperature variables. A thermal camera UAV system to measure the energy fluxes and temperatures from the earth’s surface, which are integral to understanding landscape processes and responses. Thus, UAV thermal sensors were used directly for different land cover types in and around the Faculty of Engineering building of Kocaeli University in Turkey. Derived UAV surface temperatures were compared with simultaneously acquired in situ temperature measurements. Simultaneous terrestrial temperature measurements were obtained by using TFA ScanTemp 410 model surface temperature meter. A high correlation between UAV surface temperatures and terrestrial measurements was utilized by Pearson correlation with a 0.94 coefficient. It was concluded that the UAV-mounted thermal camera system is a promising tool that has increased opportunities to understand surface temperature variability at high spatial and temporal resolution.

Biological reclamation of post-technogenic landscapes of Yakutia: problems and prospects

In the context of intensive industrial development in the Republic of Sakha (Yakutia), the issue of restoring technogenically disturbed areas is becoming increasingly relevant. Technogenic landscapes formed during the extraction of mineral deposits often have negative effects on the environment, and severe environmental conditions hinder the restoration of ecosystems affected by industrial activities. This study synthesized the long-term research results of scientists from the Research Institute of Applied Ecology of the North named after Prof., Dr. Savvinov (NEFU) on the study of succession and soil restoration processes in post-technogenic landscapes of placer deposits in the basins of the Anabar River and the Aldan River, as well as at the diamond and coal ore deposits in the Mirninsky, Aldansky and Neryungrinsky regions of Yakutia. Our study demonstrated that the effective restoration of technogenically disturbed landscapes is relevant to the use of seeds and planting materials from local flora in the biological stage of reclamation. On the dumps of ore deposits composed of rocks that are slowly weathered under hypergenesis conditions, effective restoration can be achieved only with the formation of technogenic soil. Due to the deficit of (decipher) PPP and (decipher)PSP, it is necessary to create a technology for the biological reclamation of disturbed lands with the use of alternative materials.

Hillslope and vegetation response to postglacial warming at Bear Meadows Bog, Pennsylvania, USA

AbstractConnecting changes in erosion and vegetation is necessary for predicting topographic and ecologic change in thawing permafrost landscapes. Formerly periglacial landscapes serve as potential analogs for understanding modern permafrost landscape change, yet compared to paleoenvironmental records at these sites, less is known about concurrent geomorphic processes, particularly their rates and relationships to climate change. Here, we target sediments preserved in a central Appalachian peat bog to reconstruct sedimentation across the last deglacial warming. We use ground-penetrating radar and geochemistry of cored bog sediments to quantify sedimentation timing, style, and provenance. Using 14C dating of sedimentary and geochemical shifts, we connect depositional changes to global climate and local vegetation change. We show that deglacial warming promoted deep soil disturbances via solifluction at ca. 14 ka. In contrast, relatively wetter conditions from ca. 10–9 ka promoted shallow disturbance of hillslopes via slopewash, which corresponds to a time of vegetation change. Our results highlight climate-modulated erosion depth and processes in periglacial and post-periglacial landscapes. The existence of similar erosion and vegetation records preserved regionally implies these dynamics were pervasive across unglaciated Appalachian highlands, aiding in reconstructing erosion responses to warming at a resolution with implications for predicting high-latitude landscape responses to disturbance.

De-agrarianisation and re-agrarianisation in patches: understanding microlevel land use change processes in Nepalese smallholder landscapes

ABSTRACT This paper investigates the ongoing reproduction crisis in Nepal. We utilize farmer context-specific actions of ‘hanging in’, ‘stepping out’ and ‘stepping up’ to unpack the pathways of de-activation, de-agrarianisation and re-agrarianisation in four spatially and socially differentiated landscapes. We detail a continuum of land use and labour use intensity, the microlevel variations and repertoires of actions in relation to landscape, shrinking farm sizes, labour shortages, forest expansion and increasing wildlife encroachment. The analysis focuses on specific landscape and social contexts and shows how smallholders are fine-tuning agricultural practices to meet subsistence needs. But account also must be taken of ecological variability and socially differentiated access to land to understand how households allocate labour between different land uses and between farm and off-farm activities. Household survival depends as much on the allocation of scarce labour resources as on that of scarce land. It suggests that household rather than just land has become a key unit of production.

Immersive, interactive virtual learning environments increase accessibility in soil science

AbstractAs the use of online education increases, technologies to improve the quality of learning have been improving alongside it. One method of information dissemination is virtual learning environments (VLE), in which educators can tailor digital lessons according to their subject and the needs of their students. For soil science, and field‐based sciences in general, this technology holds great potential in addressing issues of accessibility. Field labs can be challenging due to monetary, time, and physical constraints; however, the use of VLE can allow for students to indefinitely access field settings in a safe and repeatable way with no additional cost. We have built the framework for and created an immersive soil science–based VLE in the Laramie Range Mountains, examining terrain and soils along six sites on a catena. When this VLE was used in a class of 26 upper level morphology and classification students as a supplemental field trip, scores before and after use were comparable; however, students reported an increase in engagement and interest in the VLE itself, as well a general increase in understanding of relationships between landscape processes and soil formation. Using this technology structure in distance learning enhances our ability to deliver high‐quality, immersive, accessible content as natural science education progresses.

Government changes in the fisheries business landscape and assessment of their consequences for small and medium-sized businesses

The article analyzes trends in changes in the fisheries business landscape within the framework of the ongoing state policy of supporting entrepreneurship; the author's approach to revealing the content of the concept of «business landscape» in relation to modern conditions for the development of Russian entrepreneurship is formulated; The main stages of the development of small and medium-sized businesses in the modern history of Russia are systematized according to the criteria of its actual state, trends and problems. The author has examined the effectiveness of government decisions in recent years on the development of aquatic biological resources in the Far Eastern basin and identified the formation of negative changes in the Russian business landscape over the past ten years, and especially in the context of sanctions restrictions on the development of the national economy. Based on a generalization of the results of foreign and domestic research, the article proposes the author’s definition of the economic category «business landscape», which is important for management purposes, and assesses the level of participation of Russian small and medium-sized businesses in the formation of gross domestic product in comparison with developed countries. Taking into account his own long-term practice of participating in the organization of management of business structures, the author proposed a staged development of entrepreneurship in Russia over the past 30-year period; Negative changes in the business landscape are outlined using the example of fishing activities in the Far Eastern basin, establishing the imperfections of government decisions taken in recent years to increase the tax burden and complicate the procedure for obtaining fishing quotas and environmental permits for fishing entrepreneurship. The results obtained in the course of the study allow us to consider the transition to a new paradigm of state management of the development processes of the Russian fishery business landscape in the interests of all levels of entrepreneurship and the national consumer market to be considered legitimate and appropriate.

Long-term variability of the thermal state in the upper horizons of the cryolithozone in Central Yakutia

The results of the 42-year monitoring of the thermal state of permafrost landscapes in modern climate warming conditions at the “Chabyda” observation station (Central Yakutia) are presented. We studied the evolution of the variability of soil thermal state parameters: the temperature of soils on the sole of the seasonally shallow layer and in the layer of annual heat rotations, and the depth of seasonal thawing. The long-term variability of the average annual soil temperature, experiencing significant interannual and short-term fluctuations, has a multidirectional trend, with warming dominating. The main factors regulating the thermal state of permafrost landscapes are the short-period fluctuations in the snow accumulation regime. Despite significant interannual fluctuations, the depth of seasonal thawing responded to climate warming with multidirectional trends, and its increase or decrease was statistically insignificant. We performed a statistical analysis of the observation time series revealing correlations between climate elements (air temperature, total precipitation, average winter snow depth, duration of winter and summer seasons) and relationships between soil temperature regime parameters (Тξ, Т0, ξ) with climate elements. The results of these studies on the thermal state of soils can be applied to homogeneous landscapes in this region. They can also be used to model heat transfer processes in natural landscapes and develop hybrid intelligence methods for diagnosing the state of infrastructure facilities in the Far North based on high-performance computing systems.

Assessing the use of natural colonization to create new forests within temperate agriculturally dominated landscapes

There is a global drive to increase forest cover to protect biodiversity and help combat climate change. Tree planting is widely used to increase forest cover, although there is growing interest in using natural processes. However, predicting the outcome of natural colonization is challenging as it is a highly variable process and evidence is sparse, especially in temperate landscapes. Our study aims to evaluate the spatial and temporal scale over which natural colonization may be an effective approach to create new forests within temperate agriculturally dominated landscapes. We examine the spatial patterns in tree density and height across 90 sites in the United Kingdom that attempted to use natural colonization to create new forests between 1994 and 2004. Tree density and tree height were measured using light detecting and ranging point cloud data, an increasingly common technique for surveying forest characteristics. This research shows that natural colonization is a highly variable, relatively slow process in temperate agricultural landscapes, spatially restricted to a narrow fringe around existing forests and trees (105 m; 95% CI: 70–174 m, within approximately 19 years), although exact distances vary with former land use. This suggests that in some circumstances natural colonization will need to be assisted and supplemented with tree planting to increase forest cover, especially in areas away from a seed source. In reality, a blend of approaches will be needed to meet policy and land manager objectives, increase forest cover and tackle the biodiversity and climate crises.

The interactive process of cultural landscape: Taking the trails around Zhengqi Pavilion as an example

Cultural landscape is a social natural process under which people actively participate in thinking, feeling, and acting. On this basis, their connection with a certain part of the environment in turn affects people's perception of the world and the products of their actions. Trails is a representative and complex practice of integrating nature into society and transforming it into a mixed entity. However, the dynamic and diverse relationships of cultural landscapes represented by this interactive process have not been well interpreted in landscape research. The research first discusses the conceptualization and value theory of cultural landscape, and develops the methodology of cultural landscape interaction process research combining typology and Network theory. Taking the trails spontaneously formed around the Zhengqi Pavilion of Sun Yat-sen Mausoleum in Nanjing as an example, this paper discusses the interaction process of trails as a cultural landscape. Based on the analysis results, we obtained the dynamic characteristics of cultural landscapes by treating trails as a network, while obtaining the value expression created by typology.

THE RELATIONSHIP BETWEEN THE HISTORICAL DEVELOPMENT OF MUSTARD GARDEN SHAN SHUI AND CHINESE TRADITIONAL CULTURE

Landscape holds an important position in the entire history of Chinese painting. Since the Wei and Jin Dynasties, there have been many unique Shan shui. Although the characteristics of landscape styles vary in different periods and genres are diverse, the freehand brushwork spirit and artistic conception of traditional Chinese landscapes have always permeated through them. Chinese traditional landscape is a kind of art form with national characteristics and Zeitgeist connotation gradually formed through historical evolution in the process of social development and progress. This paper will start with the development process of mustard landscape and the inheritance of traditional culture, study the impact of mustard landscape on traditional culture, Zeitgeist, industry and self personality, and explore the innovative development path and significance of Chinese contemporary landscape. Relevant studies not only analyzed the reasons why landscape was widely spread in China, but also profoundly revealed the relationship between mustard garden landscape and Chinese traditional culture, and concluded that mustard garden Shan shui not only inherits Chinese culture, but also has a profound impact on Chinese culture and Chinese people's spirit, with solid theoretical research value and historical research value.

Animal and plant space-use drive plant diversity-productivity relationships.

Plant community productivity generally increases with biodiversity, but the strength of this relationship exhibits strong empirical variation. In meta-food-web simulations, we addressed if the spatial overlap in plants' resource access and animal space-use can explain such variability. We found that spatial overlap of plant resource access is a prerequisite for positive diversity-productivity relationships, but causes exploitative competition that can lead to competitive exclusion. Space-use of herbivores causes apparent competition among plants, resulting in negative relationships. However, space-use of larger top predators integrates sub-food webs composed of smaller species, offsetting the negative effects of exploitative and apparent competition and leading to strongly positive diversity-productivity relationships. Overall, our results show that spatial overlap of plants' resource access and animal space-use can greatly alter the strength and sign of such relationships. In particular, the scaling of animal space-use effects opens new perspectives for linking landscape processes without effects on biodiversity to productivity patterns.

Zmiany powierzchni leśnych na terenie Parku Krajobrazowego Puszcza Zielonka w ostatnich 180 latach w aspekcie krajobrazowym

The article presents the results of research on changes in forest areas in the PuszczaZielonka Landscape Park. An analysis of forest area transformations was carried out with the use of landscape metrics. Archival cartographic material in the form of topographic maps in the scale of 1 : 25 000, coming from four different periods (1830, 1890, 1940 and 1979/80) and a generalized Database of Topographic Object (BDOT) dated 2010, were used for the research. The result of the research are quantitative and qualitative characteristics of changes in the area and the spatial layout of the forest areas and a model of landscape processes taking place in the Puszcza Zielonka Landscape Park. The first analyzed period (1830–1890) was characterized by a small regression of forest area (index of changes WD = ‒0.05), whereas fragmentation and dissection of forest patches prevailed. The second period (1890–1940), despite the slight increase in forest areas (WD = +0.03), was characterized by a decrease in the number of patches and a reduction of their borders’ length. In the third period (1940-1979), the landscape increment process (WD = +0.27), mainly related to the filling of non-forested areas within forest complexes, prevailed. After 1979, the direction of changes was similar but on a much smaller scale (WD = +0.04).

Climate influences on future fire severity: a synthesis of climate-fire interactions and impacts on fire regimes, high-severity fire, and forests in the western United States

Abstract Background Increases in fire activity and changes in fire regimes have been documented in recent decades across the western United States. Climate change is expected to continue to exacerbate impacts to forested ecosystems by increasing the frequency, size, and severity of wildfires across the western United States (US). Warming temperatures and shifting precipitation patterns are altering western landscapes and making them more susceptible to high-severity fire. Increases in large patches of high-severity fire can result in significant impacts to landscape processes and ecosystem function and changes to vegetation structure and composition. In this synthesis, we examine the predicted climatic influence on fire regimes and discuss the impacts on fire severity, vegetation dynamics, and the interactions between fire, vegetation, and climate. We describe predicted changes, impacts, and risks related to fire with climate change and discuss how management options may mitigate some impacts of predicted fire severity, and moderate some impacts to forests, carbon, and vegetation changes post fire. Results Climate change is increasing fire size, fire severity, and driving larger patches of high-severity fire. Many regions are predicted to experience an increase in fire severity where conditions are hotter and drier and changes in fire regimes are evident. Increased temperatures, drought conditions, fuels, and weather are important drivers of fire severity. Recent increases in fire severity are attributed to changes in climatic water deficit (CMD), vapor pressure deficit (VPD), evapotranspiration (ET), and fuels. Fire weather and vegetation species composition also influence fire severity. Future increases in fire severity are likely to impact forest resilience and increase the probability of forest type conversions in many ecosystems. Conclusions Increasing warming and drying trends are likely to cause more frequent and severe disturbances in many forested ecosystems in the near future. Large patches of high-severity fire have lasting legacies on vegetation composition and structure, and impacts on tree regeneration. In some ecosystems and under certain fire-weather conditions, restoration and fuel treatments may reduce the area burned at high severity and reduce conversions from forest to non-forest conditions, increasing forest resistance and resilience to wildland fire. Thinning and prescribed fire treatments can be effective at reducing the potential for crown fire, reducing fuels, and promoting forest resilience.

Individual-Based Models for Incorporating Landscape Processes in the Conservation and Management of Aquatic Systems

Individual-Based Models for Incorporating Landscape Processes in the Conservation and Management of Aquatic Systems

Cyclic landslide-flood chains along a major mountain river

Landslides are a crucial Earth surface process in mountain landscapes, rapidly transporting large amounts of sediment into lower-elevation areas, and periodically negatively impacting people and their livelihoods. Most studies focus on their immediate, local-scale impacts, but few recognize their remote impacts in mountain environments. In particular, major landslides along rivers can block river channels to form lakes through backwater inundation, posing a flood hazard to downstream areas. In 2018, two landslides occurred along the Baige section of the Jinsha River, eastern Tibetan Plateau, forming two landslide lakes and subsequently, causing two flood events. In this study, we explore the impacts of these events on hillslopes along the river banks, upstream and downstream of the Baige site. Using small baseline subset Interferometric synthetic-aperture radar (SBAS InSAR), we find many active landslides along the Jinsha River and detect a sudden acceleration in these instabilities following the 2018 events. We attribute upstream instabilities to an increase in river width and depth, related to the remains of the landslide dam, while downstream slope instability is likely caused by undercutting along the outburst route. Modelling indicates that failure of these newly detected landslides may block the river again and potentially extend the hazard chain. This work demonstrates that landslides along major rivers can initiate new instabilities, and that even a short-lived landslide-dammed lake can have long-term impacts on stability of hillslopes in river valleys.

Reframing rangeland systems science research in Kenya: a synthesis of social-science mixed methods to inform integrative analysis of landscape pattern and process

ContextInterdisciplinary borrowing between ecology and the social sciences has produced numerous insights about pastoral livelihood practices and rangeland ecology, demonstrating how people practicing pastoralism constantly modify their practices to adapt to social, political, economic, and biophysical change.ObjectivesI outline an approach for integrating research on pastoral livelihoods into a landscape ecology framework. I focus on access to land and resources, and an integrative approach to scale, to assess the relationship between landscape and social processes.MethodsI use remotely sensed data and ethnographic analysis of livelihood change in two semi-arid contexts in Kenya to compare broad scale changes in pastoral mobility to spatio-temporal patterns of variability in rainfall and vegetation productivity. I then synthesize the political, economic, and social relations that have most prominently influenced access to land and restructured landscape process at finer scales.ResultsSpatial controls have been imposed on land use that have increasingly partitioned landscapes and concentrated pastoral access to land. Access to land has also been influenced by changes in social norms, employment, and market relations. Informal rules and norms, social differentiation, and exclusionary partitions have produced socially differentiated land use intensity gradients and novel landscape processes that have not previously been considered in landscape analyses in Kenya.ConclusionsUnderstanding access, land use, and landscape processes as intertwined, with uneven processes of land and resource capture at different scales, would enable landscape ecologists to choose observational scales relevant to rural livelihoods and sensitive to power asymmetries, creating robust analytical linkages between social and ecological processes.

Habitat fragmentation drives divergent survival strategies of a cold‐water fish in a warm landscape

AbstractClimate change is a global phenomenon, but natural selection occurs within landscapes. Many global analyses predict how climate change will shape behavior and physiology, but few incorporate information from the landscape scales at which animals actually respond to selective pressure. We compared cold‐water fish (redband trout Oncorhynchus mykiss newberrii) from neighboring habitats in a naturally warm, recently fragmented basin to understand how different responses to warming may arise from landscape constraints. Trout in warm, hydrologically connected Upper Klamath Lake fled summer temperatures and sought refuge in cool tributaries, while trout in an equally warm but fragmented reach of the Klamath River endured summer conditions. Trout in the river were more physiologically tolerant of high temperatures than trout in the lake across multiple metrics, including capacity for aerobic activity, recovery from exertion, and loss of equilibrium. Two independent metrics of energetic condition indicated that the behavioral strategy of trout in the lake came at a substantial energetic cost, while the physiological strategy of trout in the river was able to mitigate most energetic consequences of high temperatures. No clear genetic basis for increased tolerance was found in trout from the river, which may suggest tolerance was derived from plasticity, although our analysis could not rule out genetic adaptation. Our results show that landscape processes such as fragmentation can cause different climate survival strategies to emerge in neighboring populations. Connecting the mechanisms that favor similar survival strategies among related organisms at broad scales with mechanisms that drive landscape‐scale variability within taxa should be a major goal for future predictions of biological responses to climate change.

Taxonomy and genesis of soils in contrasting ecosystems of Southern Western Ghats, India

Clay minerals formed during soil formation are imprints of ecosystem functioning and pedogenic processes in landscapes. The study evaluated the variations in taxonomy, soil weathering and pedogenic changes in contrasting forest soils in the Southern Western Ghats, India. Three different forest systems with comparable soil-forming factors vis-a-vis evergreen, moist deciduous and a man-made system (rubber plantation) were evaluated for physical, chemical, morphological, and pedogenic characteristics of the related soils. Soil profiles were dug up to 1.50 m in the selected ecosystems and horizon-wise soil samples were collected. All the pedons were classified in the soil order of Ultisols and subclassified as Ustic Palehumult (evergreen forest), Ustic Haplohumult (moist deciduous forest) and Typic Haplustult (rubber plantation), respectively. The soil pH was found to be acidic in all the ecosystems ranging from 4.6 to 5.8. Chlorite, hydroxyl interlayered vermiculite (HIV), mica, kaolinite, feldspars, gibbsite and quartz dominated the mineral assemblages in the clay fractions of soils of natural forest systems. The losses of SiO2 in the non-clay fraction and corresponding enrichment of the component in the clay-sized fraction in all horizons indicated an active continuous weathering process in all the systems of this region. Clay accumulation by way of formation and translocation was highest in the lower horizons of the soils of evergreen (Bt2 at a depth range of 28–57 cm) and moist deciduous (Bt3C at a depth range of 23–150 cm) forest, whereas it was highest at Bt1 at a depth range of 15–28 cm in the plantation soil. The depth variations in the clay formations in natural and manmade forest systems provide insights into ecosystems regulated profile development under natural and man-made systems in the humid tropics, a vital information gap hitherto in soil pedogenesis of the humid tropics. Such pedogenic assessments along with the factors responsible for such modifications would provide important inputs in developing soil health management strategies in the humid tropics.