Holdridge Life Zone Classification Research Articles

Geospatial assessment of climate and human pressure on Snow Leopard habitat in the Trans-Himalayan region of Pakistan

Reliable estimates of how human activities may affect wildlife populations are critical for making scientifically sound resource management decisions. A significant issue in estimating the consequences of management, development, or conservation measures is the need to account for a variety of biotic and abiotic factors, such as land use and climate change, that interact over time altering wildlife habitats and populations. The snow leopard Panthera uncia (Schreber, 1775), as a vulnerable species, is extremely sensitive to indirect impacts of climate change. Given that it is highly difficult undertaking conservation measures on the entire range of snow leopards, identifying hotspots for conservation is necessary. This study was conducted in Bagrot and Haramosh valleys, in the Trans-Himalayan region, to evaluate the impacts of climate and human pressure on snow leopard habitat. Hybrid classification of Landsat satellite data for 2010 and 2020 was performed to elucidate land use changes that suggested a decrease in permanent snow by 10 % and 3 % in Haramosh and Bagrot while an increase in settlements cover by 16 % and 23 %, respectively. Life zone comparison for 2010 and 2020 using the Holdridge life zone (HLZ) classification system disclosed a change from three life zones to five life zones in Haramosh, and four life zones to five life zones in Bagrot, caused by a temperature increase of 2°C to 3°C, indicating that the area is becoming more and more suitable for settlements and less favorable for snow leopards. This study underlines again that mountainous regions are more vulnerable to the impacts of climate change. Warming weather is making survival more difficult for snow leopards. Although they are resilient to the direct effects of climate change, indirect impacts like avalanches, flash floods, urbanization, and human-wildlife conflict make them more vulnerable and threaten their survival. Thus, we recommend establishing further protected areas, better controlling illegal wildlife trade, and conducting genetic studies to understand impacts on snow leopards and rangeland management, livelihood improvement, and human-wildlife conflict reductions.

Climenv: Download, extract and visualise climatic and elevation data

AbstractUnderstanding the relationship between climate and vegetation requires climate data to be linked with ecological data, including habitat types and vegetation mapping. Our new R package climenv allows researchers to efficiently acquire, extract and visualise data sets that are commonly used by researchers to quantify the climatic envelope of vegetation. climenv offers integrated downloading and processing capabilities for three globally recognised data sets: WorldClim 2, CHELSA and the National Aeronautics and Space Administration's (NASA) Shuttle Radar Topography Mission (SRTM) elevation data. The package allows users to easily download and extract these data sets for single and multi‐geospatial polygon and point data sets, facilitating studies that explore the relationship between vegetation and climate. Furthermore, climenv allows users to plot traditional Holdridge life zone classification, Walter–Lieth climate diagrams and new customised plots, which combine aspects of both these systems with other biologically relevant climate variables. By enhancing the usability and flexibility of these data sets, climenv helps to explore the intricacies of the relationships between climate and vegetation. Our package is accessible from CRAN (https://CRAN.R‐project.org/package=climenv) or GitHub (https://github.com/jamestsakalos/climenv).

Identification and Characterization of Life Zones at Satipo District in the Tropics of Central Peru

At present, the life zones have undergone great changes due to anthropic activities, so the present study was carried out with the aim of identifying and characterizing the life zones of the Satipo district. The applied methodology was the Holdridge life zone classification, the meteorological variables were analyzed, the vegetation cover was identified, also using the ArcGIS, QGIS, ENVI and Microsoft Excel software, the data analysis and field information were processed. In the investigation of bioclimatic factors they show that there are four important determinants: annual biotemperature, mean annual accumulation, humidity provinces and attitudinal levels. Noticing the decline of forests, overpopulation, among others, many companies are choosing to reduce products that lead to the loss of life zones. In the district of Satipo, three life zones were identified and two of a transitory nature of the one hundred and twenty-three existing ones.

Climate Change Implications for Tropical Islands: Interpolating and Interpreting Statistically Downscaled GCM Projections for Management and Planning

AbstractThe potential ecological and economic effects of climate change for tropical islands were studied using output from 12 statistically downscaled general circulation models (GCMs) taking Puerto Rico as a test case. Two model selection/model averaging strategies were used: the average of all available GCMs and the average of the models that are able to reproduce the observed large-scale dynamics that control precipitation over the Caribbean. Five island-wide and multidecadal averages of daily precipitation and temperature were estimated by way of a climatology-informed interpolation of the site-specific downscaled climate model output. Annual cooling degree-days (CDD) were calculated as a proxy index for air-conditioning energy demand, and two measures of annual no-rainfall days were used as drought indices. Holdridge life zone classification was used to map the possible ecological effects of climate change. Precipitation is predicted to decline in both model ensembles, but the decrease was more severe in the “regionally consistent” models. The precipitation declines cause gradual and linear increases in drought intensity and extremes. The warming from the 1960–90 period to the 2071–99 period was 4.6°–9°C depending on the global emission scenarios and location. This warming may cause increases in CDD, and consequently increasing energy demands. Life zones may shift from wetter to drier zones with the possibility of losing most, if not all, of the subtropical rain forests and extinction risks to rain forest specialists or obligates.

An assessment of climate change impacts on the tropical forests of Central America using the Holdridge Life Zone (HLZ) land classification system

Ecological models have predicted shifts in forest biomes, yet there have been very few studies that have looked at the implications on carbon stocks due to these shifts. Carbon is closely correlated to biomass and constitutes an important characteristic of the forest ecosystem. It has implications for conservation and land use practices, especially for climate change mitigation strategies currently under discussion, such as REDD+. This study couples the Holdridge Life Zone (HLZ) classification with the ECHAM5 model, to evaluate the impacts of climate change using the Special Report on Emissions Scenarios (SRES) A2, A1B and B1 for the Central American region. We utilize methodologies which combine biophysical variables with model output to assess the impacts on carbon stocks for two time periods, 2000 and 2100, . Results show that overall, the tropical category of the HLZ classification gains area as a result of one type of HLZ shifting to another forest type. In many cases the shifts result in some categories of HLZ being lost in their entirety. Elevation-associated life zones are particularly vulnerable to future climatic changes. A strong point of our approach is that differences between disaggregate regional and aggregate country levels can be compared. We suggest that a critical focus of conservation and management efforts should be concentrated on where vulnerable biomes are at most risk (biomes that shift and/or reduce fall under the vulnerable category).

Predicted regional impacts of climate change on the geographical distribution and diversity of tropical forests in Costa Rica

AimSpatial models generated in a geographical information system (GIS) are utilized to predict shifts in the distribution and diversity of tropical forests in Costa Rica in response to climate change.LocationAnalyses were conducted using the Holdridge life zone classification system for the Central American country of Costa Rica.MethodsMean annual precipitation and temperature ranges were varied to reflect different magnitudes of climate change and then used to predict the distributions of nineteen forest types (life zones). Holdridge et al.'s (1971) field survey data of species richness and endemism for ten Costa Rican life zones were also analysed and considered in view of the climate change scenarios.ResultsThe scenarios indicated that shifts in the distribution of tropical forest life zones are likely to occur as a result of climatic changes. High elevation life zones were shown to be more sensitive to changes in temperature, while lower elevation life zones tended to be more sensitive to changes in precipitation. Regional life zone diversity was greatly reduced in an extreme wet and warm climate scenario. Three elevation‐associated life zones (lower montane rain forest, montane rain forest, and premontane rain forest) ranked in the top four in percentage number of endemic species. The lowland seasonally dry forest life zone ranked second in this group, suggesting that this life zone has a unique species composition in comparison with other lowland Holdridge life zones. Of the nineteen life zones, these four life zones displayed particular sensitivity to the climate changes modelled here.Main conclusionsElevation‐associated life zones may be particularly vulnerable to future climatic changes. This is also true of lowland seasonally dry forest. Geographical regions in Costa Rica that contain these life zones are likely to warrant special management and conservation attention in the event of predicted climate change.

Assessment of the vulnerability of forest ecosystems to climate change in Mexico

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 09:87-93 (1997) - DOI: https://doi.org/10.3354/cr009087 Assessment of the vulnerability of forest ecosystems to climate change in Mexico Lourdes Villers-Ruiz*, Irma Trejo-Vázquez Instituto de Geografía, Universidad Nacional Autónoma de México, Apartado Postal 20850, 04510 México, D.F. México *E-mail: villers@servidor.unam.mx An assessment of the vulnerability of forest ecosystems in Mexico to climate change is carried out on the basis of the scenarios projected by 3 climate models. A vegetation classification was performed according to 2 models, the Holdridge Life Zone Classification and the so-called Mexican Classification (a climate-vegetation classification based on typologies developed for Mexico). Projections of climate models were based on a doubled CO2 concentration condition. The models used were: the CCCM, which estimates an average increase in temperature for the country of 2.8°C and a decrease in annual precipitation of 7%; the GFDL-R30, which estimates an increase in both parameters by 3.2°C and 20% respectively; and a sensitivity model in which a homogeneous increase of 2°C in temperature and a 10% decrease in precipitation are applied throughout the country. In general, the cool temperate and warm temperate ecosystems were the most affected and tended to disappear under the conditions of the 3 scenarios. In contrast, the dry and very dry tropical forests and the warm thorn woodlands tended to occupy larger areas than at present, particularly under the conditions projected by the CCCM model. However, under the GFDL-derived scenario an increase in the distribution of moist and wet forests, which would be favoured by an increase in precipitation, was predicted. Vegetation · Mexico · Forest ecosystems · Climate change Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 09, No. 1-2. Publication date: December 29, 1997 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 1997 Inter-Research.

Modelling the Response of Vegetation in North-East China Transect to Global Change

Biogeographical models relating large-scale patterns of climate and vegetation provide a way of simulating vegetation response to global change. While scaling down these models to regional or landscape scale, climatic factors are not the only components that affect vegetation patterns; other environmental components, such as topography and parent materials, also play important roles in vegetation classification. Elevation and quaternary geology are applied as indices of topography and parent materials, along with climatic index of moisture (MI), to classify vegetation and then predict the response of vegetation in North-East China INTRODUCTION There are two approaches for development of models of global vegetation: bottom-up and the top-down. The topdown approach utilizes current equilibrium models of global vegetation patterns by relating large-scale patterns of climate and vegetation (Smith, Leemans & Shugart, 1994). This top-down approach modifies global vegetation models by defining functional types of vegetation. While scaling down global or continental models (e.g. Holdridge Life Zone Classification, Holdridge, 1967) to regional or landscape level, vegetation is affected not only by large-scale climatic factors but also by other regional environmental components, such as topography and soil parent materials. Topography alters local water balance and parent materials dominates local nutrient cycling. They are therefore useful indicators of vegetation classification in predicting vegetation response to global change. North-East China Transect (NECT) lies between 42-46? latitude and 106-134? longitude, covering an area of 700,000 km2. It has a sharp and very sensitive environmental gradient from coastal east to interior west; for example, transition of climate (primarily precipitation ranging from more than 1300 mm to less than 150 mm), soil (organic matter, C/N, efficient water, various ionic ? 1995 Blackwell Science Ltd. Transect to global change. The model is based on a vegetation classification decision rule system established by statistical analysis of environment: vegetation relationships. The classification has been validated and gives general vegetation response patterns and sensitivities to global change.

Global terrestrial vegetation 'prediction': the use and abuse of climate and application models

The Holdridge life-zone classification scheme is examined as an example of an impacts (or application) model which is already being applied to output from global climate models representing both present-day and greenhouse-warmed environments. Although intrinsically very simple, the Holdridge scheme has been modified (at least ten versions already exist in the climatic change/impacts literature) and tuned. Very different conclusions can be drawn about future distributions of continental vegetation, depending upon the version of this application model that is selected, the input used and the subsequent assessment procedure employed.

Sensitivity of terrestrial carbon storage to CO2-induced climate change: Comparison of four scenarios based on general circulation models

The potential impacts of CO2-induced climate change on terrestrial carbon storage was estimated using the Holdridge Life-Zone Classification and four climate change scenarios derived from general circulation models. Carbon values were assigned to life-zones and their associated soils from published studies. All four scenarios suggest an increase in area occupied by forests although details of predicted patterns vary among the scenarios. There is a poleward shift of the forested zones, with an increase in the areal extent of tropical forests and a shift of the boreal forest zone into the region currently occupied by tundra. Terrestrial carbon storage increased from 0.4% (8.5 Gt) to 9.5% (180.5 Gt) above estimates for present conditions. These changes represent a potential reduction of 4 to 85 ppm on elevated atmospheric CO2 levels.

Comparing global vegetation maps with the Kappa statistic

The Kappa statistic is presented as an objective tool for comparing global vegetation maps. Such maps can result from either compilations of observed spatial patterns or from simulations from models that are global in scope. The method is illustrated by comparing global maps resulting from applying a modified Holdridge Life Zone Classification to current climate and several climate change scenarios (CO 2 doubling). These scenarios were based on the results of several different general circulation models (GCMs). The direction of change in simulated vegetation patterns between different GCMs was found to be quite similar for all future projections. Although there were differences in magnitude and extent, all simulations indicate potential for enormous ecological change. The Kappa statistic proved to be a useful and straightforward measure of agreement between the different global vegetation maps. Furthermore, Kappa statistics for individual vegetation zones clearly indicated differences and similarities between those maps. The Kappa statistic was found to be most useful for rank ordering of agreement, both across a series of maps and across the various vegetation zones within a map.

Leaf Turnover Rates and Natural History of the Central American Tree Fern Alsophila salvinii

There are few studies of growth rates of tropical trees. Moreover, the growth of tree ferns in their native habitats has seldom, if ever, been studied because of their slow growth and the need to make observations over a long period of time. As a Peace Corps volunteer in El Salvador I had the chance to study the growth of the cloud forest tree fern Alsophila salvinii Hooker (Cyatheaceae). Bosque Montecristo is a cloud forest that covers about 15 km2 and is located at the common borders of El Salvador, Guatemala, and Honduras. Approximately 60 percent of the forest is in El Salvador and has been set aside as a national park and wildlife preserve. The highest point in the forest, the summit of Cerro Montecristo, has an altitude of 2414 meters. Bosque Montecristo receives an average of 2250 mm of rain annually. Fog drip during the night deposits about the same amount of water on the forest (Reyna, 1979). March and April are the driest months. The rainy season begins in mid-May or early June and continues until December. Bosque Montecristo is a subtropical, lower montane, very humid forest according to the Holdridge life zone classification (Holdridge, 1975). The cloud forest proper begins at ca. 2100 m and extends to ca. 2350 m, where it is replaced by an ericaceous shrub association on the mountain summits. The ecotone between the cloud forest and the pine-cypress association below occurs between 1900 and 2100 meters. Secondary forest is found in the whole zone wherever there has been logging (Reyna, 1979). The majority of the trees in the cloud forest are evergreen. The emergent trees in the forest canopy are principally oaks, which are thickly covered with epiphytes (Reyna, 1979). Tree trunks near the forest floor support lush growths of mosses, filmy ferns, and many other ferns such as Asplenium, Grammitis, and Elaphoglossum. Reyna (1979) reports 175 species of trees in the Montecristo area and 71 species from the cloud forest proper. In the area where the present study was undertaken three tree ferns are common: Dicksonia gigantea Karst., Trichopteris schiedeana (Presl) Tryon, and Alsophila salvinii Hooker. Alsophila salvinii is a cloud forest tree fern known from southern Mexico, Guatemala, Honduras, and El Salvador (Stolze, 1976). It is one of the most conspicuous ferns in Bosque Montecristo and is the most common tree fern. In very wet parts of the forest, A. salvinii forms large, dense thickets, often in areas where a large tree or branch has fallen. The thicket shown in Fig. I is brightly lit during the morning from holes in the forest canopy. The thicket appears to be perpetuating itself, as there are hundreds of very young tree ferns present with trunks as yet undeveloped. Fronds of these are only about 30 cm long, whereas fronds of adults are about 2.5 m long. Alsophila salvinii is also found in relatively dry, open secondary forest at ca. 2050 meters in Bosque Montecristo. The ferns in the secondary forest don't form dense