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The settlements situated on broad flat floodplains of rivers are threatened by floods during increased water flows in the rivers. The floodplain of the Dyje river situated in the area between the Nové Mlýny water reservoir and Břeclav has been protected from former annual floods since the 70s of the last century due to the water-management measures. The realised measures including the construction of the new floodway protect the town of Břeclav as well. A long-term research into the soil water regime of the floodplain forest is underway in the region. The results obtained document its historical evolution and current status. Only in the early April of 2006 (i.e. after 34 years), an unexpected "flash flood" occurred again due to a specific climatic situation. The combination of the high snow cover in higher parts of the basin and a rapid warming up caused an intensive runoff. The so-called dry polder (floodplain forests, meadows and fields) above Břeclav protected the town and its infrastructure from potential catastrophic consequences.

Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation, resulting in severe deterioration of floodplain ecosystems. Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest's restoration or protection. To balance water use for economic purposes and floodplain forest protection, the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve. The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve, and is determined directly or analytically from the curve. For the analytical approach, the problem under consideration is described by a multi-objective optimization model, which can be solved by the ideal point method. Then, the flood flow at the minimum flood stage (minimum flood flow), which is useful for flow regulation, can be calculated from the stage-discharge curve. In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream, the proposed method was used to determine the minimum flood stage and flow for the forest. Field survey of hydrology, topography, and forest distribution was carried out at typical cross sections in the floodplain. Based on the survey results, minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s. Their maximum, 393 m3/s, was considered the minimum flood flow for the study river reach. This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.

At present, the coppice-with-standards system has become so rare in floodplain forests that it is considered a natural monument. In 1990, the coppice-with-standards system was not recorded in the territory of the Czech Republic. This state contradicts the increasing interest of nature protection organizations in the relict remainders of the coppice-with-standards system, which is to be considered the closest to naturally preserved lowland forest type, and is, therefore, recommended as the final state of the biocentres and biocorridors in today's floodplain forests. The aim of this paper is to present the results of the inventory dealing with the present occurrence of the coppice-with-standards system in the floodplain forest of the Litovelské Pomoraví Protected Landscape Area (PLA) in a historical context.

This paper presents the results of an analysis of the changes in the fragmentation and ecological stability of the floodplain forest geobiocoenoses in the Protected Landscape Area Litovelské Pomoraví, Czech Republic. Using GIS methods, it was determined that the fragmentation within the study area had increased slightly and the ecological stability of the landscape had decreased slightly between the years 1938 and 2006, although the latter remained on a fairly high level. The data reflect the anthropogenic conditionality of the floodplain forest ecosystem and show that an anthropogenically conditioned geobiocoenosis may attain a relatively high level of ecological stability, this being particularly characteristic of floodplain forest geobiocoenoses in Central Europe. The results of the study contribute to the documents that will be used in drawing up a management plan for the locality important at the European level which is a part of the Natura 2000 system.

The paper deals with historical development of floodplain forests in the area of Vrapač National Nature Reserve in the floodplain of the Morava River (Protected Landscape Area Litovelské Pomoraví, Czech Republic). The aim of this paper is to contribute to a better understanding of the anthropogenic influences that have over centuries led to the present state of floodplain forests in the study area. Thus, it will be possible to define more efficiently the management plan of this floodplain forest ecosystem.

Since the mid-1970's, the landscape around the confluence of the Morava and Dyje rivers has undergone substantial changes related to the drop of water table caused by water management measures undertaken on both ri-vers. Periodical spring floods are among the phenomena lost due to ameliorations. In this study, the reaction of forest ecosystems to the decrease in soil moisture is assessed on the basis of changes in species composition of the herb layer as well as of the known requirements of individual recorded taxa and the entire herb synusiae for the water content of soils. The results confirm that the species with the greatest demand for water disappear over time. The tendency of decreasing Ellenberg indicator values of the herb layers within the phytocoenological relevés is obvious also with the consideration of the influence of different numbers of species recorded on the same plots in different years of the survey. The changes are most visible in the dampest habitats, while elevated sites, so-called "hrudy", tend to be most stable. The intensity of vegetation changes increases in direct proportion to the altitude of the sites. The process of changes in some habitats caused by the alteration of the water regime has to be separated from the changes in the vegetation structure, which are easier to observe optically. The limiting factor of their development in the given conditions is the forest wildlife. After the elimination of wildlife's influence, the woody species synusia differentiates in height. A qualitative shift is represented by the recession of the formerly dominant Quercus robur on the main level, and its gradual replacement by other species. The impact of changes going on in the woody synusia on selected characteristics of the herb layer are included in the analyses.

Seasonally inundated native forest fragments ("ipucas") located in natural landform depression swales of the Araguaian Plain are currently under land use pressure. Their composition needs to be better understood to guarantee their protection. This comparative study of fragments under different land use conditions was carried out at Lago Verde Farm, Lagoa da Confusão,Tocantins, Brazil. The location coordinates are UTM 643586 and 644060 East and 8792795 and 8799167 North. This study aimed to first analyze and compare the floristic composition of two seasonally inundated forest fragments of approximately one hectare each. The first is located in an intact (without human intervention) Gramineous-Woody Savanna region and the second in a rice cultivation region. The floristic composition of both fragments was then compared to that of other wetland forests located in the Northern, Central Western and Southeastern regions of Brazil.All the floristic compositions are affected by seasonal flooding and soil water saturation. The floristic inventory used a census method that sampled all trees and shrubs with perimeter at 1.30 m from soil (PAP) = 15cm; 665 individuals, 33 families and 49 species were recorded for the intact region and 807 individuals, 35 families and 70 species for the altered region fragment. The values of H' = 0.806 (Shannon-Weaver) and J = 3.44 nats /individual (equability) for the fragment in the region affected by rice cultivation are considered high compared to the intact region fragment values (H' = 0.761 and J = 2.97). Families contributing to floristic richness in the altered region fragment were Fabaceae (9 species), Vochysiaceae (6) and Annonaceae (4). In the intact region fragment, Fabaceae also presented the largest number of species (8) followed by Arecaceae, Chrysobalanaceae and Vochysiaceae (3 each). When comparing the forests from various regions in Brazil, floristic similarity was found to be small. Greater similarity was found when indices for the two Lagoa da Confusão fragments were compared to riparian forests located in the Federal District of Brasilia.Os fragmentos naturais de florestas inundáveis conhecidos como Ipucas localizam-se na planície do Araguaia, sob a forma de depressões naturais, estando atualmente sob forte pressão antrópica. Este estudo foi desenvolvido na fazenda Lago Verde, Lagoa da Confusão em Tocantins, entre as coordenadas UTM 643586 e 644060 leste e 8792795 e 8799167 norte. Os objetivos deste trabalho foram analisar e comparar a composição florística de dois fragmentos de florestas inundáveis de aproximadamente 1 ha cada, sendo um inserido em área de Savana Gramíneo-Lenhosa sem intervenção antrópica e outro em área de orizicultura, com outras florestas também sob influência de inundações sazonais e, ou, saturação hídrica do solo das Regiões Norte, Centro-Oeste e Sudeste. O levantamento florístico foi realizado através do método de Censo, em que foram amostrados todos os indivíduos arbustivo-arbóreos com perímetro a 1,30 m do solo (PAP) = 15 cm. Como resultado, foram apresentados 807 indivíduos, 35 famílias e 70 espécies na área antropizada e 665 indivíduos, 33 famílias e 49 espécies na área preservada. Os valores de H´ (Shannon-Weaver) e J (equabilidade) da área que está sob influência da orizicultura, 3,44 nats/indivíduo e 0,806, respectivamente, podem ser considerados altos em relação ao outro fragmento, onde os valores foram de 2,97 nats/indivíduo e 0,761. As famílias que contribuíram para a riqueza florística na floresta inundável com intervenção antrópica foram Fabaceae (9), Vochysiaceae (6) e Annonaceae (4). Na floresta inundável em área preservada, Fabaceae também apresentou maior riqueza, com oito espécies, seguidas de Arecaceae, Chrysobalanaceae e Vochysiaceae (3) cada. A similaridade florística foi baixa entre todas as florestas comparadas, porém maior semelhança foi encontrada entre florestas ripárias do Distrito Federal e entre as duas florestas inundáveis deste estudo.

Este trabalho apresenta a flora de espécies arbóreas e palmeiras na floresta estacional semidecidual na planície aluvial do rio Doce, uma área de cerca de 20.000 ha, a partir de Linhares (ES) até próximo à foz no oceano atlântico. Foram determinadas 408 espécies (27 classificadas em gênero) e 59 famílias, entre arbóreas e palmeiras. Por meio da análise de agrupamento, foi evidenciado que a floresta do rio Doce é muito semelhante floristicamente à floresta estacional dos tabuleiros terciários, que estas se agrupam com as florestas estacionais do rio Doce em MG e que, por sua vez, todas estas se agrupam com as florestas ombrófilas do sul da Bahia, sendo o conjunto nitidamente separado das outras formações ombrófilas costeiras. Foram encontradas dezenas de espécies deocorrência restrita ou pouco frequentes em levantamentos na floresta atlântica, enfatizando a importância da área para conservação da biodiversidade. Pelo fato das matas de cacau na região abrangerem mais de 80% dessa área, sugere-se a delimitação de uma Área de Proteção Ambiental, que permita conciliar o cultivo do cacau com a proteção da biodiversidade.The tree and palm flora was studied in the Atlantic forest of the rio Doce alluvial floodplain, in a 20,000ha area, between Linhares (Espírito Santo State) and the Atlantic Ocean. The floristic survey recorded 408 species and 59 families. Floristic composition was compared to other forests of São Paulo, Minas Gerais, Bahia and Rio de Janeiro states using cluster analysis. The forest flora of the study area was most similar to that of forests in Espírito Santo, Minas Gerais, and Bahia. Dozens of species in the study area are restricted and rare in Atlantic forest; this area deserves special attention for biodiversity conservation. The Brazilian government should pay heed to the biological importance of this area and declare it an Environmental Protection Area, a type of conservation unit where sustained exploitation of resources is legal. We understand that, in practical terms, this sort of conservation unit is not very efficient in conserving natural resources, but it would be a start and might contribute to improved awareness, especially by local farmers and politicians.

Nature, ecosystems and biodiversity provide human society with many benefits known as ecosystem services. Functional diversity is an important aspect of biodiversity. In this paper, we applied inductive approach to the identification, mapping and evaluation of ecosystem services of the Aegopodio-Alnetum glutinosae community in Tribeč Mts. The results from 2015 show that the alder floodplain forest represents one of the most productive forest ecosystems with seasonal maximum production of 59.03 g m-2, species diversity of N0 = 40 and functional diversity of FD = 10. The forage potential of this community is medium, the melliferous potential is high and the therapeutic potential was estimated as extremely rich in medicinal plants. From the functional groups for providing ecosystem services, woody plants and hemicryptophytes play the most significant role. [ABSTRACT FROM AUTHOR]

Fire is an increasingly important agent of forest degradation in the Amazon, but little attention has been given to the susceptibility of seasonally flooded forests to fire. Satellite images suggest that forests flooded seasonally by nutrient-poor black waters are more susceptible to fire and may suffer greater fire damage than nearby upland forests. Reasons for this difference may include the presence of a root mat, more fine fuel as litter and a drier understory in the flooded forest. We investigated this difference in the field, hypothesizing that differences in the aboveground structure of the pre-burn forest can contribute to the difference in impacts of, and susceptibility to, fires. We employed a portable profiling LiDAR (PPL), first to compare damage between adjacent black water seasonally flooded and upland forests that were burned by the same fire event, and to then assess pre-fire canopy structure attributes known to affect fire susceptibility. For both assessments, we used PPL-derived metrics of leaf area and vertical and horizontal variation in the structure of vegetation in the canopy. Four years after the fire, the LiDAR metrics showed greater combined effects of high damage and slow recovery in the seasonally flooded forest; reduction of total Leaf Area Index (LAI) after burning was only 10% for upland forest but was 71% in the flood forest. Compared to unburned upland, the canopy of unburned flood forest had structural differences that increase susceptibility to fire, including drier microclimate. It had more gaps, a more open understory and a lower upper canopy. Small patches lacking canopy closure (LAI < 1.0) were far more abundant in the unburned flood forest. We conclude that black water seasonally flooded forest suffers greater fire damage than upland forest and canopy structure contributes to its greater susceptibility to the occurrence of fires. This must be considered in assessments of future Amazon fire risks and impacts, including flood forest acting as a potential conduit for spreading fire to upland forest. [ABSTRACT FROM AUTHOR]

The structure and diversity of the epilithic and epiphytic diatom community and their relationship with the physicochemical parameters of the Acarlar Floodplain Forest were studied. Also, diatom indices and their applicability as a tool for estimating the floodplain water quality were tested. Diatoms were sampled monthly from February 2011 to January 2012 at three sites. A total of 94 taxa were identified. Approximately 76% of the diatom taxa are cosmopolitan distribution for Turkey. The diatom ecological indicator values, Trophic Diatom Index (TDI), Saprobic Index (SI), Swiss Diatom Index (DI-CH), THE "Indice de polluo-sensibilité spécifique", also named IPS and Trophic Diatom Index for Lakes (TDIL) were evaluated. TDI, SI and TDIL showed good relationships with environmental variables. A principal component analysis (PCA) was performed on environmental data. The results of PCA separated the second station with high specific conductance, hardness and NO3-N concentrations. It also showed that physicochemical parameters were affected by temperature and water level. Canonical Correspondence Analysis (CCA) was carried to determine the relationship between the diatom distributions and environmental variables. The results of CCA bi plot showed that specific conductance, hardness, turbidity, pH, dissolved oxygen, oxygen saturation and nutrients were significantly correlated with species distribution. According to the CCA result, two diatom groups were separated. [ABSTRACT FROM AUTHOR]

Plants are connected to habitats by functional traits which are filtered by environmental gradients. Since tree species composition in the forest canopy can influence ecosystem processes by changing resource availability, litter accumulation, and soil nutrient content, we hypothesised that non-native invasive trees can establish new environmental filters on the understorey communities. In the hardwood floodplain forests in Northern Italy, the invasive trees Robinia pseudoacacia L. and Prunus serotina Ehrh. are the dominant canopy species. We used trait data assembled from databases and iterative RLQ analysis to identify a parsimonious set of functional traits responding to environmental variables (soil, light availability, disturbance, and stand structure) and the dominant native and invasive canopy species. Then, RLQ and fourth-corner analysis was conducted to investigate the joint structure between macro-environmental variables and species traits and functional groups were identified. The trait composition of the herb-layer was significantly related to the main environmental gradients and the presence of the invaders in the canopy showed significant relationships with several traits. In particular, the presence of P. serotina may mitigate or even erase the effect of disturbances, maintaining a stable forest microclimate and thus favouring 'true' forest species, while R. pseudoacacia may slow down forest succession and regeneration by establishing new stable associations with a graminoid-dominated understorey. The impact of the two invasive trees on herb layer composition appears to differ, indicating that different management and control strategies may be needed. [ABSTRACT FROM AUTHOR]

River regulation induces immediate and chronic changes to floodplain ecosystems. We analysed both short-term and prolonged effects of river regulation on the growth patterns of the keystone riparian tree species Fremont cottonwood ( Populus deltoides ssp. wislizenii) at three upper Colorado River Basin rivers having different magnitudes of flow regulation. We compared cottonwood basal area increment on (i) the regulated Upper Green River below Flaming Gorge Dam; (ii) the adjacent free-flowing Yampa River; and (iii) the partially regulated Lower Green River below their confluence. Our goal was to identify the hydrologic and climatic variables most influential to tree growth under different flow regimes. A dendrochronological analysis of 182 trees revealed a long-term (37 years) trend of declining growth during the post-dam period on the Upper Green, but trees on the partially regulated Lower Green maintained growth rates similar to those on the reference Yampa River. Mean annual, mean growing season, and peak annual discharges were the multicollinear flow variables most correlated to growth during both pre-dam and post-dam periods at all sites. Annual precipitation was also highly correlated with tree growth, but precipitation occurring during the growing season was poorly correlated with tree growth, even under full river regulation conditions. This indicates that cottonwoods rely primarily on groundwater recharged by river flows. Our results illustrate the complex and prolonged effects of flow regulation on floodplain forests, and suggest that flow regulation designed to simulate specific aspects of flow regimes, particularly peak flows, may promote the persistence of these ecosystems. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the phytosociological structure of floodplain forests in the Euxine region of Turkey was examined from a large-scale perspective. For this goal, all of the published relevés were analyzed using the numerical classification and ordination techniques, which are widely used in phytosociological studies all over the world. In summary, a syntaxonomical scheme for floodplain forests with 11 communities (five associations and one alliance were newly identified) was suggested as follows: Fraxino angustifoliae - Ulmetum laevis Slavić 1952 allerietosum petiolatae Kavgacı et al. subass. nov. hoc loco; Fraxino angustifoliae - Ulmetum laevis Slavić 1952 junglandetosum regiae Kavgacı et al. 2011; Leucojo aestivi - Fraxinetum angustifoliae Glavač 1959 alnetosum glutinosae Glavač 1959; Smilaco excelsae - Fraxinetum angustifoliae Pavlov et Dimitrov 2002 prunellotosum vulgaris Pavlov et Dimitrov 2002; Apocyno veneti - Fraxinetum angustifoliae (Özen 2010) Kavgacı et al. ass. nov. hoc loco; Euphorbio strictae - Fraxinetum angustifoliae (Aydogdu 1988) Kavgacı et al. ass. nov. hoc loco (Alno - Quercion, Populetalia alba, Salici purpureae - Populetea nigrae); Aro hygrophyli - Fraxinetum angustifoliae (Kutbay et al. 1998) Kavgacı et al. ass. nova hoc loco; Pterocaryo pterocarpae - Alnetum barbatae Quézel et al. 1992; Platanthero chloranthae - Fraxinetum oxycarpae Korkmaz et al. 2012; Sambuco ebuli - Alnetum barbatae (Korkmaz et al. 2012) Kavgacı et al. ass. nov. hoc loco (Periploco graecae - Fraxinion angustifoliae Kavgacı et al. all. nova hoc loco, Populetalia alba, Salici purpureae - Populetea nigrae); and Geranio robertiani - Carpinetum betuli Kavgacı et al. 2011 (Carpino betuli - Fagion orientalis, Rhododendro pontici - Fagetalia orientalis, Querco - Fagatea). [ABSTRACT FROM AUTHOR]

Floodplain forests and the woody debris they produce are major components of riverine ecosystems in many arid and semiarid regions (drylands). We monitored breakdown and nitrogen dynamics in wood and bark from a native riparian tree, Fremont cottonwood ( Populus deltoides subsp. wislizeni ), along four North American desert streams. We placed locally-obtained, fresh, coarse material [disks or cylinders (∼500–2000 cm 3 )] along two cold-desert and two warm-desert rivers in the Colorado River Basin. Material was placed in both floodplain and aquatic environments, and left in situ for up to 12 years. We tested the hypothesis that breakdown would be fastest in relatively warm and moist aerobic environments by comparing the time required for 50% loss of initial ash-free dry matter ( T 50 ) calculated using exponential decay models incorporating a lag term. In cold-desert sites (Green and Yampa rivers, Colorado), disks of wood with bark attached exposed for up to 12 years in locations rarely inundated lost mass at a slower rate ( T 50 = 34 yr) than in locations inundated during most spring floods ( T 50 = 12 yr). At the latter locations, bark alone loss mass at a rate initially similar to whole disks ( T 50 = 13 yr), but which subsequently slowed. In warm-desert sites monitored for 3 years, cylinders of wood with bark removed lost mass very slowly ( T 50 = 60 yr) at a location never inundated (Bill Williams River, Arizona), whereas decay rate varied among aquatic locations ( T 50 = 20 yr in Bill Williams River; T 50 = 3 yr in Las Vegas Wash, an effluent-dominated stream warmed by treated wastewater inflows). Invertebrates had a minor role in wood breakdown except at in-stream locations in Las Vegas Wash. The presence and form of change in nitrogen content during exposure varied among riverine environments. Our results suggest woody debris breakdown in desert riverine ecosystems is primarily a microbial process with rates determined by landscape position, local weather, and especially the regional climate through its effect on the flow regime. The increased warmth and aridity expected to accompany climate change in the North American southwest will likely retard the already slow wood decay process on naturally functioning desert river floodplains. Our results have implications for designing environmental flows to manage floodplain forest wood budgets, carbon storage, and nutrient cycling along regulated dryland rivers. [ABSTRACT FROM AUTHOR]

Copyright of Caldasia is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the years 1993–2001 the monitoring of the soil surface invertebrates was carried out in the flood- plain forest in the Ranšpurk National Nature Reserve (Southern Moravia). The dynamics of carabid beetles is described in detail in this paper. A total of 8 529 individuals belonging to 67 carabid species was collected. The most abundant species were Pterostichus niger (Schaller, 1783), Nebria brevicollis (Fabricius, 1792), Carabus ullrichi Germar, 1824, Carabus violaceus Linnaeus, 1758, Abax carinatus (Duftschmid, 1812), Patrobus atrorufus (Stroem, 1768), Pterostichus melanarius (Illiger, 1798), Carabus granulatus Linnaeus, 1758, Poecilus cupreus (Linnaeus, 1758), Bembidion mannerheimi C. R. Sahlberg, 1827 and Epaphius secalis (Paykull, 1790). During the years 1993–1996 the species composi- tion indicated especially the drainage of the locality. In July 1997, a disastrous flood affected all groups of invertebrates, including the carabids. The abundance of hygrophilous species increased extremely during the years after the flood. The summer flood showed that the submersion of the soil surface had higher impact on carabid taxocenoses than flooding by system of canals.

Despite a natural history interest in the early 1900s, relatively little ecological research has been carried out in the Rio Purús basin of central Amazonia, Brazil. Here we describe a new study area in the region of Lago Uauaçú with an emphasis on the climate, forest structure and composition, and soil characteristics between adjacent unflooded (terra firme) and seasonally inundated forests; situated within both the white-water (várzea) and black-water (igapó) drainage systems that dominate the landscape. The climate was found to be typical of that of the central Amazon. Várzea forest soils had high concentrations of nutrients, while terra firme and igapó soils were comparatively nutrient-poor. Terra firme forests were the most floristically diverse forest type, whereas várzea was intermediate, and igapó the most species-poor. The Lecythidaceae was the most important family in terra firme while the Euphorbiaceae was the most important in both várzea and igapó. There were significant differences between forest types in terms of number of saplings, canopy cover and understorey density. In contrasting our results with other published information, we conclude that the Lago Uauaçú region consists of a typical central Amazonian forest macro-mosaic, but is a unique area with high conservation value due to the intimate juxtaposition of terra firme, várzea and igapó forests.

The subject of our research was to verify effects of the mechanical preparation of soil in the natural regeneration of pedunculate oak in a floodplain forest. On the site of a hard-wooded floodplain forest at the confluence of the Morava and Dyje rivers (Czech Republic), several sample plots were established differing in the preparation of soil during regeneration, in weeding the plots and in the period of the implementation of soil surface scarification before and after the fall (or distribution) of acorns. On the basis of results obtained, mechanical preparation of soil on non-weed-infested plots in the heavy seed year is not necessary, however, it supports seedling emergence from acorns and eliminates weed tree emergence and weed. However, it is better to realize it only after the fall of acorns and to incorporate them into soil and thus their emergence will be increased. Soil scarification can be carried out also in the course of harvesting the parent stand through the extraction of wood and slash from the regenerating area. In weed-infested stands, however, the thorough preparation of soil before the fall of acorns appears to be a necessity.

During the years 1993–2001 the monitoring of the soil surface fauna was carried out in a floodplain fo- rest in the Ranšpurk National Nature Reserve (south Moravia). The harvestmen assemblages fluctuation is described in detail in this paper. The method of pitfall traps was used. A total of 3174 individuals of seven harvestmen species were collected. The species composition was very similar to other research results from the southern Moravian floodplain forest. Only the dominance values differ from the values in the other localities. All of the registered species prefer moisture and shadow places. The highest abundance was observed in Astrobunus laevipes (Canestrini, 1872), Nemastoma lugubre (Müller, 1776), Oligolophus tridens (C. L. Koch, 1936) and Rilaena triangularis (Herbst, 1799). The dynamics of harvestmen occurrence during the year had a different development than in other groups of invertebrates. Harvestmen mostly occurred in pitfall traps in autumn and winter months. The highest abundance of harvestmen in traps was observed in December and January. In July 1997, disastrous flood affected all groups of invertebrates. The flood had a minimal impact on the abundance of harvestmen in pitfall traps.

Floodplain forest response to changed soil moisture regime and nutrient availability due to river regulation was studied using remote sensing (ETM) data. Images of May and October 2001 were used to prepare NDVI, SAVI, 5/4-ratio images and ETM band 7. Comparisons of the LAI, NDVI, 5/4-ratios and ETM band 7 mean values were done to find out the differences between the flooded and non-flooded sites. Unsupervised clustering of images was done using single transformed channels, i.e. NDVI, SAVI, 5/4-ratio and ETM band 7 to find seasonal variations in the values of these indices. The results were found to be in agreement with ground research.