Syntaxonmical revision of azonal forest vegetation with dominance of Alnus glutinosa and A. incana was done along a latitudinal transect of Slovakia. A data matrix consisting of 240 phytosociological ...relevés was obtained in accordance with the standard Zürich-Montpellier approach. Detrended correspondence analysis was used to clarify the relationships between the vegetation composition and environmental variables, whereas one-way ANOVA was applied to quantify the differences in site requirements of particular vegetation types. The unsupervised numerical classification resulted in identification of five clusters corresponding to the traditionally described and ecologically interpretable associations within the Euro-Siberian alder carr forests of Alnion glutinosae and the European broad-leaved floodplain forests of Alnion incanae: Carici elongatae-Alnetum glutinosae Schwickerath 1933 (alder carr forests on permanently waterlogged soils), Stellario-Alnetum glutinosae Lohmeyer 1957 (riparian alder vegetation on mesic to humid sites along small brooks), Piceo-Alnetum Mráz 1959 (submontane and montane oligotrophic spruce-alder forests on waterlogged habitats), Cardamino amarae-Alnetum incanae Šomšák 1961 (grey alder vegetation in spring fed areas) and Alnetum incanae Lüdi 1921 (submontane and montane streamside grey alder forests on mesic sites). They significantly (P < 0.05) differed in the Ellenberg's indicator values for nutrients, moisture, temperature and altitude. These environmental variables were also established by DCA analysis as underlying sources of variation in alder-dominated forest composition. Special attention was given to discussion of their syntaxonomy, nomenclature, floristic structure, ecological features and distribution.
Context
Expansion of urban settlements has caused observed declines in ecosystem services (ES) globally, further stressing the need for informed urban development and policies. Incorporating ES ...concepts into the decision making process has been shown to support resilient and functional ecosystems. Coupling land change and ES models allows for insights into the impacts and anticipated trade-offs of specific policy decisions. The spatial configuration of urbanization likely influences the delivery and production of ES.
Objective
When considering multiple ES simultaneously, improving the production of one ecosystem service often results in the decrease in the provision of other ES, giving rise to trade-offs. We examine the impact of three urban growth scenarios on several ES to determine the degree to which spatial configuration of urbanization and the development of natural land cover impacts these services over 25 years.
Methods
We couple land change and ES models to examine impacts to carbon sequestration, surface water-run off, nitrogen and phosphorus export, organic farming and camping site suitability, to determine trade-offs among the six ES associated with each spatial configuration for western North Carolina.
Results
Consequences of urban configurations are dramatic, with degraded ES across all scenarios and substantial variation depending on urban pattern, revealing trade-offs. Counter-intuitive trade-offs between carbon sequestration and lands available for organic farming and camping were observed, suggesting that no configurations result in mutual benefits for all ES.
Conclusions
By understanding trade-offs associated with urban configurations, decision makers can identify ES critical to an area and promote configurations that enhance those.
In spite of increasing point density and accuracy, airborne lidar point clouds often exhibit point density variations. Some of these density variations indicate issues with point clouds, potentially ...leading to errors in derived products. To highlight these issues, we provide an overview of point density variations and show examples in six airborne lidar point cloud datasets that we used in our topographic and geospatial modeling research. Using the published literature, we identified sources of point density variations and issues indicated or caused by these variations. Lastly, we discuss the reduction in point density variations using decimations, homogenizations, and their applicability.
The phytosociological research of the oak forest vegetation was carried out in the northern part of the Štiavnické vrchy Mts (Central Slovakia) using the standard Zürich-Montpellier approach. The ...data set consisting of 41 phytosociological relevés was obtained by the authors in two vegetation seasons in 2008 and 2009. The numerical classification and the ordination methods were applied to determine the main vegetation types and to explain the structure of the vegetation-environmental data matrix, respectively. Four associations within two classes were distinguished: Luzulo albidae-Quercetum petraeae Hilitzer 1932, typical for shallow, mineral-poor and acidic soils, Melico uniflorae-Quercetum petraeae Gergely 1962 occuring on mesic stands with skeletal and deeper soils, Poo nemoralis-Quercetum dalechampii Šomšák et Háberová 1979 developing on moderately canopyopened stands in the submontane belt, Sorbo torminalis-Quercetum Svoboda ex Blažková 1962 growing on moderately acidic substrates in drier regions. The major environmental gradients responsible for variation in forest species composition was associated with soil nutrient and soil reaction following the Ellenberg indicator values as well as the measured environmental variables (C/N-ratio and soil acidity). Special attention was given to the discussion on species composition and site ecology.
Fitocenološke raziskave hrastovih gozdov v severnem delu gorovja Štiavnické vrchy (srednja Slovaška) smo naredili po Zürichško-Montpellierski metodi. Enainštirideset vegetacijskih popisov smo naredili v dveh vegetacijskih sezonah v letih 2008 in 2009. Za določitev glavnih vegetacijskih tipov in za obrazložitev strukture podatkovne matrike vegetacijskih popisov in ekoloških spremenljivk smo uporabili numerično klasifikacijo in ordinacijo. Znotraj dveh razredov smo ločili štiri asociacije: Luzulo albidae-Quercetum petraeae Hilitzer 1932, značilna za plitva, z minerali revna, kisla tla, Melico uniflorae-Quercetum petraeae Gergely 1962, ki se pojavlja na mezičnih rastiščih s skeletnimi, globljimi tlemi, Poo nemoralis-Quercetum dalechampii Šomšák et Háberová 1979, ki se razvije v zmerno odprtih sestojih v submontanskem pasu, Sorbo torminalis-Quercetum Svoboda ex Blažková 1962 pa uspeva na zmerno kislih tleh v sušnejših predelih. Glavna okoljska gradienta, ki vplivata na floristično sestavo, sta hranila v tleh in reakcija tal. Odražata se tako v Ellenbergovih indikatorskih vrednostih kot v merjenih okoljskih spremenljivkah (C/N razmerje in kislost tal). Poseben poudarek smo namenili diskusiji o vrstni sestavi in ekologiji rastišč.
In some regions of Slovakia, black alder forest vegetation has not been documented appropriately yet. This paper is the first vegetation study presenting the phytosociological data and measured ...environmental parameters from the western part of central Slovakia. The data set was classified by using a modified TWINSPAN algorithm, which allowed us to discern floristically and ecologically distinctive plant communities. They correspond to the associations Stellario nemorum-Alnetum glutinosae Lohmeyer 1957 (riparian alder vegetation on mesic to humid sites along small brooks) and Carici acutiformis-Alnetum glutinosae Scamoni 1935 (eutrophic black alder carr forests in the colline zone) with the variants of Ligustrum vulgare and Galium palustre. The community Carici elongatae-Alnetum glutinosae Schwickerath 1933 (mesotrophic to eutrophic alder carr vegetation growing on permanently waterlogged soils), documented only with two phytosociological relevés, was distinguished following expert knowledge. A floristic and ecological pattern of these associations is presented.
The major compositional gradients were interpreted based on Ellenberg’s indicator values and the values of environmental variables recorded during the field sampling in the growing season 2011. The principal component analysis revealed the importance of soil moisture, light availability, portion of open water and soil surface for species composition variability at the association level, whereas the variants of Carici acutiformis-Alnetum glutinosae were sorted along the acidity gradient.
Gozdna vegetacija črne jelše dosedaj v nekaterih predelih Slovaške še ni bila dovolj raziskana. Članek predstavlja prvo vegetacijsko raziskavo fitocenoloških popisov in merjenih rastiščnih dejavnikov iz zahodnega dela osrednje Slovaške. Podatkovni niz smo klasificirali z modificiranim TWINSPAN algoritmom, s čemer smo lahko floristično in ekološko ločili značilne rastlinske združbe. Ugotovili smo asociaciji: Stellario nemorum- -Alnetum glutinosae Lohmeyer 1957 (obvodna črnojelševja na srednje do vlažnih rastiščih ob manjših potokih) in Carici acutiformis-Alnetum glutinosae Scamoni 1935 (evtrofna črnojelševja v kolinskem pasu) z dvema variantama Ligustrum vulgare in Galium palustre. Asociacijo Carici elongatae-Alnetum glutinosae Schwickerath 1933 (mezotrofni do eutrofni črnojelševi grezi, ki uspevajo na tleh stalno prepojenih z vodo), ki je dokumentirana samo z dvema popisoma smo določili na podlagi strokovnega poznavanja.
Prikazali smo floristični in ekološki vzorec pojavljanja teh asociacij. Glavni gradienti so pojasnjeni na podlagi Ellenbergovih indikatorskih vrednosti, ekološki dejavniki pa so bili merjeni med terenskim vzorčenjem v vegetacijski sezoni 2011. Analiza glavnih komponent je razkrila pomen vlažnosti tal, svetlobe, deleža odprtih vodnih in talnih površin za variabilnost vrstne sestave na nivoju asociacij, medtem ko se varianti asociacije Carici acutiformis-Alnetum glutinosae ločita na gradientu kislosti.
The study presents phytosociological and ecological data from azonal black alder forest sites in the southern part of central Slovakia. A data set of 29 relevés was collected by authors in vegetation ...season 2010 following the standard Braun-Blanquet approach. Numerical classification was performed to delimit the main vegetation types, while statistical analyses were applied to explain the vegetation-environmental relationships. Three associations within two classes were distinguished using a TWINSPAN algorithm. Carici elongatae-Alnetum glutinosae Schwickerath 1933 is an alder carr forest occurring on waterlogged soils in spring fed areas and alluvial zones along rivers. Carici acutiformis-Alnetum glutinosae Scamoni 1933 represents an alder carr forest on habitats with stagnant or slowly flowing water along water courses and artificial water reservoirs. Mesic to humid stands along small brooks are typical for the riparian alder vegetation of Stellario-Alnetum glutinosae Lohmeyer 1957. A detailed description of the floristic and ecological features of these associations is presented. The major environmental gradients affecting variation in species composition of these communities were interpreted as a response of vegetation to soil moisture and nutrient availability regarding the Ellenberg indicator values (moisture and nutrients) and measured variables (total N and C).
V članku so predstavljeni fitosociološki in ekološki podatki iz azonalnih gozdov črne jelše v južnem delu osrednje Slovaške. V vegetacijskem obdobju leta 2010 smo naredili 29 popisov po standardni Braun-Blanquetovi metodi. Z numerično klasifikacijo smo opredelili glavne vegetacijske tipe, s statističnimi metodami pa pojasnili povezavo med vegetacijo in okoljskimi dejavniki. Z algoritmom TWINSPAN smo ločili tri asociacije znotraj dveh razredov. V asociacijo Carici elongatae-Alnetum glutinosae Schwickerath 1933 uvrščamo jelševe greze na rastiščih z visoko talno vodo ob potokih in na aluvialnih ravninah ob rekah. Asociacija Carici acutiformis-Alnetum glutinosae Scamoni 1933 predstavlja jelševe gozdove na rastiščih z zastajajočo ali počasi tekočo vodo ob vodotokih in umetnih vodnih telesih. Mezofilni do vlažni sestoji ob majhnih potokih so značilni za asociacijo Stellario-Alnetum glutinosae Lohmeyer 1957. V članku so podrobno opisane floristična sestava in rastiščne značilnosti teh asociacij. Glavni ekološki gradienti, ki se kažejo v vrstni sestavi, so talna vlaga in hranila. Med Ellenbergovimi indikatorskimi vrednostmi sta to vlažnost in hranila, med merjenimi spremenljivkami pa skupni N in C.
Learning to use geographic information system (GIS) software effectively may be intimidating due to the extensive range of features it offers. The GRASS GIS software, in particular, presents ...additional challenges for first-time users in terms of its complex startup procedure and unique terminology associated with its data structure. On the other hand, a substantial part of the GRASS user community including us as developers recognized and embraced the advantages of the current approach. Given the controversial nature of the whole issue, we decided to actively involve regular users by conducting several formal surveys and by performing usability testing. Throughout this process, we discovered that resolving specific software issues through pure user-centered design is not always feasible, particularly in the context of open-source scientific software where the boundary between users and developers is very fuzzy. To address this challenge, we adopted the user-centered methodology tailored to the requirements of open-source scientific software development, which we refer to as community-driven design. This paper describes the community-driven redesigning process on the GRASS GIS case study and sets a foundation for applying community-driven design in other open-source scientific projects by providing insights into effective software development practices driven by the needs and input of the project’s community.
Abstract
Impacts of sea level rise will last for centuries; therefore, flood risk modeling must transition from identifying risky locations to assessing how populations can best cope. We present the ...first spatially interactive (i.e., what happens at one location affects another) land change model (FUTURES 3.0) that can probabilistically predict urban growth while simulating human migration and other responses to flooding, essentially depicting the geography of impact and response. Accounting for human migration reduced total amounts of projected developed land exposed to flooding by 2050 by 5%–24%, depending on flood hazard zone (50%–0.2% annual probability). We simulated various “what-if” scenarios and found managed retreat to be the only intervention with predicted exposure below baseline conditions. In the business-as-usual scenario, existing and future development must be either protected or abandoned to cope with future flooding. Our open framework can be applied to different regions and advances local to regional-scale efforts to evaluate potential risks and tradeoffs.
As rapid urbanization occurs in cities worldwide, the importance of maintaining updated digital elevation models (DEM) will continue to increase. However, due to the cost of generating ...high-resolution DEM over large spatial extents, the temporal resolution of DEMs is coarse in many regions. Low-cost unmanned aerial vehicles (UAS) and DEM data fusion provide a partial solution to improving the temporal resolution of DEM but do not identify which areas of a DEM require updates. We present Rapid-DEM, a framework that identifies and prioritizes locations with a high likelihood of an urban topographic change to target UAS data acquisition and fusion to provide up-to-date DEM. The framework uses PlanetScope 3 m satellite imagery, Google Earth Engine, and OpenStreetMap for land cover classification. GRASS GIS generates a contextualized priority queue from the land cover data and outputs polygons for UAS flight planning. Low-cost UAS fly the identified areas, and WebODM generates a DEM from the UAS survey data. The UAS data is fused with an existing DEM and uploaded to a public data repository. To demonstrate Rapid-DEM a case study in the Walnut Creek Watershed in Wake County, North Carolina is presented. Two land cover classification models were generated using random forests with an overall accuracy of 89% (kappa 0.86) and 91% (kappa 0.88). The priority queue identified 109 priority locations representing 1.5% area of the watershed. Large forest clearings were the highest priority locations, followed by newly constructed buildings. The highest priority site was a 0.5 km2 forest clearing that was mapped with UAS, generating a 15 cm DEM. The UAS DEM was resampled to 3 m resolution and fused with USGS NED 1/9 arc-second DEM data. Surface water flow was simulated over the original and updated DEM to illustrate the impact of the topographic change on flow patterns and highlight the importance of timely DEM updates.
Models that are both spatially and temporally dynamic are needed to forecast where and when non-native pests and pathogens are likely to spread, to provide advance information for natural resource ...managers. The potential US range of the invasive spotted lanternfly (SLF, Lycorma delicatula) has been modeled, but until now, when it could reach the West Coast's multi-billion-dollar fruit industry has been unknown. We used process-based modeling to forecast the spread of SLF assuming no treatments to control populations occur. We found that SLF has a low probability of first reaching the grape-producing counties of California by 2027 and a high probability by 2033. Our study demonstrates the importance of spatio-temporal modeling for predicting the spread of invasive species to serve as an early alert for growers and other decision makers to prepare for impending risks of SLF invasion. It also provides a baseline for comparing future control options.
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