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1.
We used the PnET-II model of forest carbon and water balances to estimate regional forest productivity and runoff for the northeastern United States. The model was run at 30 arc sec resolution (approximately 1 km) in conjunction with a Geographic Information System that contained monthly climate data and a satellite-derived land cover map. Predicted net primary production (NPP) ranged from 700 to 1450 g m2 yr1 with a regional mean of 1084 g m2 yr1. Validation at a number of locations within the region showed close agreement between predicted and observed values. Disagreement at two sites was proportional to differences between measured foliar N concentrations and values used in the model. Predicted runoff ranged from 24 to 150 cm yr1with a regional mean of 63 cm yr1. Predictions agreed well with observed values from U.S. Geologic Survey watersheds across the region although there was a slight bias towards overprediction at high elevations and underprediction at lower elevations.Spatial patterns in NPP followed patterns of precipitation and growing degree days, depending on the degree of predicted water versus energy limitation within each forest type. Randomized sensitivity analyses indicated that NPP within hardwood and pine forests was limited by variables controlling water availability (precipitation and soil water holding capacity) to a greater extent than foliar nitrogen, suggesting greater limitations by water than nitrogen for these forest types. In contrast, spruce-fir NPP was not sensitive to water availability and was highly sensitivity to foliar N, indicating greater limitation by available nitrogen. Although more work is needed to fully understand the relative importance of water versus nitrogen limitation in northeastern forests, these results suggests that spatial patterns of NPP for hardwoods and pines can be largely captured using currently available data sets, while substantial uncertainties exist for spruce-fir.  相似文献   

2.
The Illinois Geographic Information System was used to compare the soil and landscape attributes of the State with its historic vegetation, current land use, and patterns of land-use change over the past 160 years. Patch structural characteristics among land types in four geographic zones were also compared. The assessment of patch characteristics revealed a highly modified State with most land patches controlled by human influences and relatively few by topographic and hydrologic features. Correlation and regression analyses determined the relationships of land type and abundance within each of 50 general soil associations to properties of the soil associations - typically slope, texture, organic matter, productivity index, and available waterholding capacity. The distribution of the historic vegetation of the State and its current deciduous forests and nonforested wetlands related moderately (r2 0.44) to various landscape attributes. Urban and other highly modified land types were less closely related.  相似文献   

3.
A general framework of ecosystem hotspots suggests variation in soil metabolic activity can be understood through the relative distribution and intensity of patches of disproportionately high ecosystem process rates. To better understand the causes of soil metabolic spatial variability and the variation in ecosystem hotspots we quantified soil respiration (R) spatial heterogeneity across a network of seven sites spanning a 2,489 m elevation gradient in the Santa Rosa Mountains of Southern California. At each site, soil samples were collected from 0–5 and 5–15 cm soil depths at 2 m intervals along three 100 m transects. Each soil sample was analyzed for organic matter content (SOM) and was incubated at 40% water holding capacity for 20 days. R was measured at days 5 and 20. Strong contrasts were observed between the relationships of soil physical variables and R at scales of individual landscapes and the whole region. Notably, the relationship between SOM and R was positive within individual landscapes and negative across the entire region. Plant canopy microenvironments were associated with elevated SOM and R relative to the interspaces. This microenvironment effect on R was reduced by elevation, incubation interval, and soil depth. Geostatistical analyses conducted individually for each site identified an increasing range of autocorrelation from 2 to 10 m and a decreasing proportion of variation that was included in this range with elevation. These results suggest hotspots increase in size but decrease in intensity with elevation thereby creating a maximum hotspot effect at middle elevations.  相似文献   

4.
A Geographic Information System (GIS) was used to analyze how beaver (Castor canadensis) have altered the hydrology and vegetation of Voyageurs National Park, Minnesota over a 46-year period. Maps of beaver ponds prepared from 1940, 1948, 1961, 1972, 1981, and 1986 aerial photographs were analyzed with a rasterbased based GIS to determine impoundment hydrology and vegetation distributions for each map date. Overlay and classification techniques were used to quantify hydrologic and vegetation changes between map dates. The GIS was superior to manual methods for some analyses (e.g., area measurement), and indispensible for others (e.g., transition analysis). Total area impounded increased from 1% to 13% of the landscape between 1940 and 1986, as the beaver population increased from near extirpation to a density of 1 colony/km2. Most of the impoundment area increase occurred during the first two decades, when 77% of cumulative impoundment area was flooded. Once impounded ≥60% of the area maintained the same water depth or vegetation during any decade. GIS procedures were combined with field data to show that available nitrogen stocks nearly tripled between 1940 and 1986 as a result of beaver impoundment.  相似文献   

5.
Zhang  Minghua  Geng  Shu  Ustin  Susan L. 《Landscape Ecology》1998,13(1):37-54
Quantitative agricultural landscape indices are useful to describe functional relationships among climatic conditions, groundwater dynamics, soil properties and agricultural land use for mathematical models. We applied methods of regression statistics, variance component estimation and a Geographical Information System (GIS) to construct indices describing crops and soils and to establish functional relationships among these variables. This paper describes the development of indices and the partitioning of the spatial and temporal variation in groundwater models using the data from Tulare County, California, which was selected as the study area. Indices of ground surface elevation, total crop water demand, soil water infiltration rate, and soil production index explain 91% of the variation in average spring groundwater level. After relating spatial patterns of groundwater use to indices of crop and soil properties, we found that mean groundwater use is positively related to total crop water demand and soil water infiltration rate while the variation in groundwater use was negatively correlated with the crop water demand and soil water infiltration rate and positively related to soil water holding capacity. The spatial variation in groundwater use was largely influenced by crops and soil types while the temporal variation was not. We also found that groundwater use increased exponentially with decreasing annual precipitation for most townships. Based on these associations, groundwater use in each township can be forecast from relative precipitation under current methods of agricultural production. Although groundwater table depth is strongly affected by topography, the statistically significant indices observed in the model clearly show that agricultural land use influences groundwater table depth. These simple relationships can be used by agronomists to make water management decisions and to design alternative cropping systems to sustain agricultural production during periods of surface water shortages.  相似文献   

6.
A multi-scale spatial ecological model of a wet sclerophyllous forest subject to recurrent fires is presented. The model is specified in a Discrete Event Systems framework (DEVS) (Zeigler, 1990) interfaced with a Geographic Information System (GIS), and includes the ability to simulate landscape dynamics at several levels of resolution simultaneously. This is achieved by encoding a modular hierarchical representation of the forest landscape components into a set of nested, interconnected, and spatially referenced dynamic models. The results of the landscape dynamics simulations are displayed as sequences of maps through time, illustrating the potential of this modeling methodology for dealing with complex hierarchical structures that operate at several spatial and temporal resolutions.Research work supported by Junta Nacional de Investigaçäo Científica e Tecnológica, Portugal, and the Advanced Resource Technology Program, University of Arizona, USA.  相似文献   

7.
To determine the dynamics of the spatial extent of gallery forest on Konza Prairie Research Natural Area (KPRNA), aerial photographs taken over a 46 year time frame were digitized into an ARC-INFO Geographic Information System (GIS). A Global Positioning System (GPS) was used to collect ground control points to co-register the photographs for each year. Gallery forest areas for the three major drainage boundaries (Kings Creek, Shane Creek, and White Pasture) were analyzed to assess the uniformity of change in the landscape system. Results indicated that the total gallery forest area on KPRNA has increased in area from 157 ha in 1939 to over 241 ha in 1985. During this time, there was an increase in the total number of patches and a decrease in the mean size of forest patches. However, the rate of increase was not consistent over this time period, nor was it uniform from one drainage basin or stream order to another. Detailed spatial analysis of the forested area with a geomorphology and digital elevation model of Konza Prairie showed that in 1985, 58% of the forest was on alluvial/colluvial soil, yet only 15% of that soil type was forested. In addition, over 70% of the forest was on the 0–15% slope interval, but only 15–20% of that slope interval was forested. These results may be attributed to a variety of factors such as changing management practices (i.e., frequency of fires and herbicide spraying) and the temporal constraints on extent to which the gallery forest can expand across the landscape.  相似文献   

8.
Accurate information on existing residential landscapes is essential for framing ordinances and monitoring residential water use in the Urban Greenspace Ecosystem. We classified residential landscapes of New Mexico's largest city, Albuquerque, to explore the spatial distribution of residential greenspace and its composition among zip codes and median incomes. Geographic Information System (GIS) vector files including parcels, city limits, zip codes and land-use maps, were integrated with ownership information. The database was stratified by Albuquerque's 16 zip codes. Four hundred eighty residential landscapes were selected randomly for study. Very high spatial resolution (0.15 m) 2008 true color aerial photographs and the object-oriented supervised classification module in ENVI EX were used to identify residential features. Spatial and textural variables, created by image segmentation, were classified using the K-Nearest Neighbor (K-NN) algorithm embedded in ENVI EX. Classification accuracy was 89%. Larger greenspace, tree, shrub, and grass areas were in larger parcels. Landscapes in lower income groups and older zip codes include larger greenspace and tree cover because of mature tree sizes, while grass dominated landscapes of higher income groups and newer zip codes. This knowledge of residential vegetation distribution could serve as a basis for policy makers, planners, and water conservation officers wishing to enact ordinances and regulations that govern the urban residential landscape.  相似文献   

9.
Several factors affecting stocks of soil organic-C have been identified, including climate, soil texture, and drainage, but how these factors and their influence vary spatially is not well documented. The State Soil Geographic Data Base (STATSGO) was used to estimate soil organic-C stocks of Montana and Kansas and to map spatial variation of soil properties. Regressions across map units of area-weighted estimates of soil organic-C, clay content, and drainage class show that clay content is positively correlated with organic-C in Kansas, but that drainage class is a better indicator of soil with high and low organic-C stocks in Montana. About 85% of Kansas is covered by Mollisols. These grasslands of the North American Great Plains are where the paradigm relating clay content to stabilization of soil organic-C was developed. In contrast, clay content does not covary with soil organic-C across Montana. Only 30% of Montana is covered by Mollisols; the remainder includes rangeland, covered primarily by Aridisols and Entisols, and forests, covered by Inceptisols, Spodosols, and Histosols. Although other unidentified factors contribute to spatial variation in soil organic-C stocks in Montana, drainage class distinguishes the C-rich and the C-poor soils. When taken with similar results correlating soil C stocks with drainage class in a separate study of Maine, soil wetness emerges as an important controller of soil organic-C in northern states of the USA. Another objective was to compare STATSGO estimates (1:250,000 scale) of area covered by soil orders with estimates from the FAO/UNESCO Soils Map of the World (1:5,000,000). Agreement was excellent in Kansas and reasonably good in Montana. When used with regionally specific estimates for soil-C, the FAO map holds promise for regional and global extrapolation of soil C stocks.  相似文献   

10.
Mapping and analyzing landscape patterns   总被引：5，自引：0，他引：5  
Landscapes were mapped as clusters of 2 or 3 land cover** types, based on their pattern within the clusters and tendency for a single type to dominate. These landscapes, called Landscape Pattern Types (LPTs), were combined with other earth surface feature data in a Geographic Information System (GIS) to test their utility as analysis units. Road segment density increased significantly as residential and urbanized land cover components increased from absent, to present as patch, to present as matrix (i.e., the dominant land cover type). Stream segment density was significantly lower in LPTs with an urbanized or residential matrix than in LPTs with either a forest or agriculture matrix, suggesting an inverse relationship between stream network density and the prevalence of human development other than agriculture in the landscape. The ratio of average forest patch size to total forest in the LPT unit decreased as agriculture replaced forest, then increased as residential and urban components dominated. Wetland fractal dimension increased as agriculture and residential land cover components of LPTs increased. Comparison of LPT and LUDA land cover area statistics in ecoregions suggested that land cover data alone does not provide information as to its spatial arrangement.  相似文献   

11.
Geographic Information Systems (GIS) and web-based GIS platforms are typically used by large organizations and government agencies for the purpose of data storage, query, analysis, and spatial data mapping. Google Fusion Tables, however, provides cloud-based computing services for data management and easy user collaboration through the Google Maps interface. Fusion Tables are oriented towards smaller organizations that previously were unable to publish data online due to limitations of database knowledge, high cost of start-up, and restrictions on implementation. In this research project, we assess the functionality and limitations of Fusion Tables and associated API as a spatial data management system by programming an interactive web-based mapping platform, the CityTrees.ca Project, designed to showcase the benefits of trees growing on the campus of Ryerson University, Toronto. Specifically, Fusion Tables functionality, such as data storage and manipulation, is used to build a query interface (both attribute and spatial) that permits users of CityTrees.ca to search for and map trees by species, diameter, height, and location. We found that Fusion Tables performed well as a storage medium for our campus tree data, which could easily be explored through our creation of a JavaScript-enabled query tool. Our project provides a unique roadmap for small to medium-sized urban forestry organizations and environmental non-profits seeking to create interactive mapping applications where data privacy and advanced spatial analysis are not fundamental.  相似文献   

12.
Spatially-distributed estimates of biologically-driven CO2 flux are of interest in relation to understanding the global carbon cycle. Global coverage by satellite sensors offers an opportunity to assess terrestrial carbon (C) flux using a variety of approaches and corresponding spatial resolutions. An important consideration in evaluating the approaches concerns the scale of the spatial heterogeneity in land cover over the domain being studied. In the Pacific Northwest region of the United States, forests are highly fragmented with respect to stand age class and hence C flux. In this study, the effects of spatial resolution on estimates of total annual net primary production (NPP) and net ecosystem production (NEP) for a 96 km2 area in the central Cascades Mountains of western Oregon were examined. The scaling approach was a simple `measure and multiply' algorithm. At the highest spatial resolution (25 m), a stand age map derived from Landsat Thematic Mapper imagery provided the area for each of six forest age classes. The products of area for each age class and its respective NPP or NEP were summed for the area wide estimates. In order to evaluate potential errors at coarser resolutions, the stand age map was resampled to grain sizes of 100, 250, 500 and 1000 m using a majority filter reclassification. Local variance in near-infrared (NIR) band digital number at successively coarser grain sizes was also examined to characterize the scale of the heterogeneity in the scene. For this managed forest landscape, proportional estimation error in land cover classification at the coarsest resolution varied from –1.0 to +0.6 depending on the initial representation and the spatial distribution of the age class. The overall accuracy of the 1000 m resolution map was 42% with respect to the 25 m map. Analysis of local variance in NIR digital number suggested a patch size on the order of 100–500 m on a side. Total estimated NPP was 12% lower and total estimated NEP was 4% lower at 1000 m compared to 25 m. Carbon flux estimates based on quantifying differences in total biomass stored on the landscape at two points in time might be affected more strongly by a coarse resolution analysis because the differences among classes in biomass are more extreme than the differences in C flux and because the additional steps in the flux algorithm would contribute to error propagation. Scaling exercises involving reclassification of fine scale imagery over a range of grain sizes may be a useful screening tool for stratifying regions of the terrestrial surface relative to optimizing the spatial resolution for C flux estimation purposes.  相似文献   

13.
Scaling up ecosystem processes from plots to landscapes is essential for understanding landscape structure and functioning as well as for assessing ecological impacts of land use and climate change. This study illustrates an upscaling approach to studying the spatiotemporal pattern of ecosystem processes in the Changbai Mountain Nature Reserve in northeastern China by integrating simulation modeling, GIS, remote sensing data, and field-based observations. The ecosystem model incorporated processes of energy transfer, plant physiology, carbon dynamics, and water cycling. Using a direct extrapolation scheme, the patch-level ecosystem model was scaled up to quantify the landscape-level pattern of primary productivity and the carbon source-sink relationship. The simulated net primary productivity (NPP) for the entire landscape, consisting of several ecosystem types, was 0.680 kg C m−2 yr−1. The most widely distributed ecosystem type in this region was the mixed broad-leaved and Korean pine (Pinus koraiensis) forest, which had the highest NPP (1.084 kg C m−2 yr−1). The total annual NPP for all ecosystem types combined was estimated to be 1.332 Mt C yr−1. These results suggest that the Changbai Mountain landscape as a whole was a carbon sink, with a net carbon sequestration rate of about 0.884 Mt C yr−1 for the study period. The simulated NPP agreed reasonably well with available field measurements at a number of locations within the study landscape. Our study provides new insight into the relationship between landscape pattern and ecosystem processes, and useful information for improving management practices in the Changbai Mountain Nature Reserve, which is one of the most important forested landscapes in China. Several research needs are discussed to further refine the modeling approach and reduce prediction uncertainties.  相似文献   

14.
In this article we demonstrate how to integrate the ecosystem services concept into regional planning using the example of a case study in Saxony, Germany. We analysed how the reduction of water erosion as a regulating service impacts six other ecosystem services. Ecological integrity, provisioning services (provision of food and fibre, provision of biomass), regulating services (soil erosion protection, drought-risk regulation, flood regulation), and the cultural service landscape aesthetics are taken into account. Using a decision support software, we found that the greening of preferential discharge paths can reduce water erosion by 2–7 %. The introduction of hedgerows and the change in the soil management system from tillage to no-till practices revealed a reduction in the total soil loss by 33 and 89 %, respectively. A combination of the three erosion control measures—greening, hedgerows, and no-till management—reduced the soil loss most efficiently by 92 %. We found synergies between the measures for reducing erosion and the provision of ecological integrity, of regulating and cultural ecosystem services. In contrast, the impact on provisioning services was slightly negative. For the land use planning in the case study region we recommend therefore a combination of greening, hedges, and management change. We found that the applied integrated ecosystem services assessment approach, in combination with stakeholder involvement in the scenario development, helped communicating cross-sectoral effects of different management strategies in a comprehensive way and therefore supports regional planning.  相似文献   

15.
Of particular importance in shaping species assemblages is the spatial heterogeneity of the environment. The aim of our study was to investigate the influence of spatial heterogeneity and environmental complexity on the distribution of ant functional groups and species diversity along altitudinal gradients in a temperate ecosystem (Pyrenees Mountains). During three summers, we sampled 20 sites distributed across two Pyrenean valleys ranging in altitude from 1,009 to 2,339 m by using pitfall traps and hand collection. The environment around each sampling points was characterized by using both physical and land-cover variables. We then used a self-organizing map algorithm (SOM, neural network) to detect and characterize the relationship between the spatial distribution of ant functional groups, species diversity, and the variables measured. The use of SOM allowed us to reduce the apparent complexity of the environment to five clusters that highlighted two main gradients: an altitudinal gradient and a gradient of environmental closure. The composition of ant functional groups and species diversity changed along both of these gradients and was differently affected by environmental variables. The SOM also allowed us to validate the contours of most ant functional groups by highlighting the response of these groups to the environmental and land-cover variables.  相似文献   

16.
A proximity-based approach to assessing habitat   总被引：2，自引：0，他引：2  
Planning for either a single species, multiple species, or ecosystems is greatly dependent on spatial interactions in the landscape. Problems exist for evaluating wildlife habitat changes over large ranges of space and time. This paper illustrates the use of Geographic Information Systems (GIS) to evaluate habitat for a single species, ruffed grouse (Bonasa umbellus), following a time series of forest harvests. A habitat suitability model for ruffed grouse is utilized on a two-township study area in north-central Minnesota to assess the habitat suitability changes over time using an even-aged area-control harvesting plan. The results are presented as a habitat quality change map and a contingency table, representing the movement of habitat class areas between time periods resulting from the proposed harvesting. We developed a neighborhood definition to allow for spatially varying habitat values. This work illustrates the ability to look ahead and around in estimating the impact on wildlife habitat resulting from alternative future management activities.Now with the U.S. Forest Service, Sitka, AK 99835.  相似文献   

17.
In 2015, 17 Sustainable Development Goals were outlined within the 2030 Agenda by the United Nations. Objective 11.7 aims to provide universal access to safe, inclusive, and accessible green and public spaces, highlighting the strategic role of these areas in cities. In the international literature, the theory of Ecosystem Services (ESs) has been developed to raise public awareness of the need to preserve biodiversity, enhance community cohesion, civic identity, and quality of life. In this study, we explored the economic value of Singapore's Urban Green Infrastructures (UGI) by investigating the private condominium and apartment unit market through the Hedonic Pricing Method (HPM). The HPM was integrated with Geographic Information System (GIS) to spatialize housing units, measure the distance of different green spaces, and consider the dependence effects among housing unit transactions. The results highlighted a positive effect on values of the proximity to the natural green areas, as well as to the regional, city parks, and small nature areas. The annual benefits of UGIs on households within 800 m range from 10,305,275 USD for nature areas to 59,723,703 USD for the city parks and 74,011,689 USD for the regional parks. Estimates showed the small contribution of park connectors (PCN) and neighborhood parks. The HPM results are a useful aid to understanding the amenity value of UGIs. The modeling outcomes could be used to inform policymakers and municipal green managers about UGIs preservation and new allocation starting from households’ preferences.  相似文献   

18.
There are only a few studies of land cover-land use changes which provide an integrated assessment of the biophysical and societal causes and consequences of environmental degradation in Ethiopia. Our objectives were to determine the status of the environmental degradation, analyse and evaluate the relationships among vegetation, geomorphological and socio-economic factors contributing to environmental degradation, and propose opportunities for rehabilitation of these natural resources. Field and other environmental data in northern Ethiopia and those acquired by remote sensing techniques were used to accomplish these objectives. These were integrated with socio-economic data obtained from official sources using a Geographic Information System (GIS).Spatial information such as the percent of land cover-land use types and geomorphological categories, and the percent of each land cover-land use type in the geomorphological categories were calculated using Geographic Information System (GIS). The three most dominant features of the geomorphological categories (93.0%) are scarps and denuded rock slopes, erosion surfaces and badlands, while the three most dominant features in the land cover-land use types (71.3%) are croplands, open woodlands and bushlands. Badlands account for 38.7% of the geomorphological units and 41.8% of the croplands currently occur on badlands. Simple and partial correlation analyses were applied to explore the extent of the interaction between the anthropogenic and the natural system. The anthropogenic system is influenced by elevation, which is positively correlated with human population and livestock densities and area of croplands. The natural system finds its place only on steep slopes as shown by the positive correlation between woodland,slope, high potential erosion, scarps and denudational rock slopes. The study indicates that agriculture in the study area is in a critical environmental situation. A change of paradigm in land-use and development is needed to encourage participation of the landowners and users in the efforts to conserve the vegetation and the soil. This study provides sound options that could be used to rehabilitate the vegetation directly and to alleviate the current pressure on the land and improve human welfare indirectly. Matching the human and livestock densities with the carrying capacity of the land through recruitment of the surplus labour force for a modern economy, resettlement,off-farm employment and intensification of agriculture are t he long and short-term actions that may contribute to the rehabilitation of the degraded areas. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.

Context

Data for biophysically modeled and Public Participatory GIS (PPGIS)-derived cultural ecosystem services have potential to identify natural resource management synergies and conflicts, but have rarely been combined. Ecosystem service hot/coldspots generated using different methods vary in their spatial extent and connectivity, with important implications.

Objectives

We map biophysically modeled and PPGIS-derived cultural services for six U.S. national forests using six hot/coldspot delineation methods. We evaluate the implications of hotspot methods for management within and outside of designated wilderness areas.

Methods

We used the ARIES and SolVES modeling tools to quantify four biophysically modeled and 11 largely cultural ecosystem services for six national forests in Colorado and Wyoming, USA. We mapped hot/coldspots using two quantile methods (top and bottom 10 and 33 % of values), two area-based methods (top and bottom 10 and 33 % of area), and two statistical methods (Getis-Ord Gi* at α = 0.05 and 0.10 significance level) and compare results within and outside wilderness areas.

Results

Delineation methods vary in their degree of conservatism for hot/coldspot extents and spatial clustering. Hotspots were more common in wilderness areas in national forests near the more densely populated Colorado Front Range, while coldspots were more common in wilderness areas in more urban-distant forests in northwest Wyoming.

Conclusions

Statistical hotspot methods of intermediate conservatism (i.e., Getis-Ord Gi*, α = 0.10 significance) may be most useful for ecosystem service hot/coldspot mapping to inform landscape scale planning. We also found spatially explicit evidence in support of past findings about public attitudes toward wilderness areas.
  相似文献   

20.

Context

In the Rio Grande Plains of southern Texas, subtropical savanna vegetation is characterized by a two-phase pattern consisting of discrete woody patches embedded within a C4 grassland matrix. Prior trench transect studies have suggested that, on upland portions of the landscape, large woody patches (groves) occur on non-argillic inclusions, while small woody patches (clusters) are dispersed among herbaceous vegetation where the argillic horizon is present.

Objective

To test whether spatial heterogeneity of subsurface soil texture drives the landscape-scale pattern of woody patches in this subtropical savanna.

Methods

Landscape-scale spatial patterns of soil texture were quantified by taking spatially-specific soil samples to a depth of 1.2 m in a 160 m × 100 m plot. Kriged maps of soil texture were developed, and the locations of non-argillic inclusions were mapped.

Results

Visual comparison of kriged maps of soil texture to a high resolution aerial photograph of the study area revealed that groves were present exclusively where the non-argillic inclusions were present. This clear visual relationship was further supported by positive correlations between soil sand concentration in the lower soil layers and total fine root biomass which mapped the locations of groves.

Conclusions

Subsurface non-argillic inclusions may favor the establishment and persistence of groves by enabling root penetration deeper into the profile, providing greater access to water and nutrients that are less accessible on those portions of the landscape where the argillic horizon is present, thereby regulating the distribution of grove vegetation and structuring the evolution of this landscape.
  相似文献   

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