Zooplankton generation following inundation of floodplain soils: effects of vegetation type and riverine connectivity

2017 ◽  
Vol 68 (1) ◽  
pp. 76 ◽  
Author(s):  
Alicia K. Catlin ◽  
Kevin J. Collier ◽  
Ian C. Duggan
Keyword(s):  
Community Composition ◽  
Vegetation Type ◽  
Juvenile Fish ◽  
Zooplankton Community ◽  
Soil Conditions ◽  
Native Forest ◽  
Soil Cores ◽  
Forest Remnants ◽  
Soil Temperatures ◽  
Zooplankton Production

We investigated the potential for zooplankton to emerge following inundation of dry soils on the lower Waikato River floodplain, North Island, New Zealand. Soil cores were collected from native forest remnants, scrub (predominantly Salix spp.) and pasture, and from sites inside or outside of stopbanks, to examine the effects of vegetation type and hydrological disconnection. We hypothesised that more larger-bodied zooplankton would emerge from forested floodplain areas, and that areas with high connectivity with the river would produce more zooplankton. Zooplankton appeared from soil cores within 3 days of wetting and no new taxa arose after 12 days. Community composition differed between vegetation types, with larger bodied cladocerans and copepods dominating forested and scrub sites, and rotifers dominating pastoral sites. Connectivity did not play a statistically significant role in determining community composition. Soil conditions were implicated as important in affecting emergent zooplankton community composition, with copepods and cladocerans characteristic of sites with wetter soils and bdelloid rotifers abundant in open sites with higher soil temperatures. Our findings indicate scrub and forested floodplains can be important areas for large-bodied zooplankton production, and that maintaining vegetative heterogeneity on floodplains may promote trophic subsidies for migrating juvenile fish as floodwaters subside.

scholarly journals Simulation of Daily Mean Soil Temperatures for Agricultural Land Use Considering Limited Input Data

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 441
Author(s):  
Philipp Grabenweger ◽  
Branislava Lalic ◽  
Miroslav Trnka ◽  
Jan Balek ◽  
Erwin Murer ◽  
...  
Keyword(s):  
Soil Temperature ◽  
Input Data ◽  
Agricultural Land ◽  
Soil Column ◽  
Soil Conditions ◽  
Snow Layer ◽  
Time Step ◽  
Soil Temperatures ◽  
Dimensional Simulation ◽  
Limited Input Data

A one-dimensional simulation model that simulates daily mean soil temperature on a daily time-step basis, named AGRISOTES (AGRIcultural SOil TEmperature Simulation), is described. It considers ground coverage by biomass or a snow layer and accounts for the freeze/thaw effect of soil water. The model is designed for use on agricultural land with limited (and mostly easily available) input data, for estimating soil temperature spatial patterns, for single sites (as a stand-alone version), or in context with agrometeorological and agronomic models. The calibration and validation of the model are carried out on measured soil temperatures in experimental fields and other measurement sites with various climates, agricultural land uses and soil conditions in Europe. The model validation shows good results, but they are determined strongly by the quality and representativeness of the measured or estimated input parameters to which the model is most sensitive, particularly soil cover dynamics (biomass and snow cover), soil pore volume, soil texture and water content over the soil column.

scholarly journals Complementary Use of Magnetometric Measurements for Geochemical Investigation of Light REE Concentration in Anthropogenically Polluted Soils

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 457
Author(s):  
Piotr Fabijańczyk ◽  
Jarosław Zawadzki
Keyword(s):  
Soil Samples ◽  
Soil Conditions ◽  
Soil Cores ◽  
Light Rare Earth ◽  
Polluted Soils ◽  
Chemical Measurements ◽  
Geochemical Investigation ◽  
Light Rare Earth Elements ◽  
Soil Magnetic Susceptibility ◽  
Geophysical Measurements

The purpose of this study was to use fast geophysical measurements of soil magnetic susceptibility (κ) as supplementary data for chemical measurements of selected light rare earth elements (REEs) in soil. In order to ensure diversity in soil conditions, anthropogenic conditions and types of land use, seven areas were selected, all located in regions subjected to past or present industrial pollution. Magnetometric parameters were measured using a selected magnetic sensor that was specially designed for measurements of soil cores and were used to classify collected soil cores into six distinctive types. The analysis of REEs concentrations in soil was carried out taking into account the grouping of collected soil samples based on the type of study area (open, forested and mountain), and additionally on the measured magnetometric parameters of collected soil cores. A use of magnetometric measurements provided different, but complementary to chemical measurements information, which allowed to obtain deeper insight on REEs concentrations in soils in studied areas.

scholarly journals White Root Rot of Raspberries

1951 ◽  
Vol 4 (3) ◽  
pp. 211
Author(s):  
GC Wade
Keyword(s):  
Soil Moisture ◽  
Root Rot ◽  
Soil Moisture Content ◽  
Soil Conditions ◽  
Causal Organism ◽  
White Root Rot ◽  
High Soil Moisture ◽  
High Soil ◽  
Soil Temperatures ◽  
Dry Soil

The disease known as white root rot affects raspberries, and to a less extent loganberries, in Victoria. The causal organism is a white, sterile fungus that has not been identified. The disease is favoured by dry soil conditions and high soil temperatures. It spreads externally to the host by means of undifferentiated rhizomorphs; and requires a food base for the establishment of infection. The spread of rhizomorphs through the soil is hindered by high soil moisture content and consequent poor aeration of the soil.

scholarly journals PERFIL DOS INCÊNDIOS FLORESTAIS NO BRASIL DE 1994 A 1997

FLORESTA ◽  
2002 ◽  
Vol 32 (2) ◽  
Author(s):  
Ronaldo Viana Soares ◽  
Juliana Ferreira Santos
Keyword(s):  
Forest Fire ◽  
Vegetation Type ◽  
Secondary Growth ◽  
Minas Gerais ◽  
Size Class ◽  
Fire Season ◽  
Burned Area ◽  
Native Forest ◽  
Fire Statistics ◽  
Fire Control

O conhecimento do perfil dos incêndios florestais é muito importante para o planejamento do controle dos mesmos. O objetivo deste trabalho foi estabelecer o perfil dos incêndios florestais no país através de dados coletados, em áreas protegidas, no período de 1994 a 1997, através de formulários preenchidos por empresas e instituições florestais. Foram registrados e informados 1.957 incêndios e apesar deste número não representar a totalidade dos incêndios ocorridos no período estudado, constituiu-se numa base confiável para se conhecer as principais características dos incêndios. Os resultados mostraram que a área média atingida por incêndio no período analisado foi de aproximadamente 135 ha, sendo Minas Gerais o estado líder, tanto em número de incêndios informados (62,7% do total) como em área queimada (25,2%). O grupo Incendiários foi a principal causa dos incêndios, com 56,6% das ocorrências, vindo a seguir as Queimas para limpeza com 22,1%. Com relação à área queimada o grupo Queimas para limpeza , com 74,1% da superfície atingida, foi a principal causa, ficando o grupo Incendiários em segundo lugar com 19,8%. A principal estação de incêndios no país se estende de julho a novembro, quando ocorreram 79,2% dos incêndios, correspondendo a 98,6% da área atingida. O maior número de incêndios (39,7% das ocorrências) foi registrado em Outro tipo de vegetação, que inclui cerrado, capoeira e campo. Com relação à área atingida, entretanto, 92,5% foi registrada em Florestas Nativas. Quanto à distribuição dos incêndios através das classes de tamanho, 23,9% foi enquadrado na classe I ( 0,1 ha). É importante ressaltar que quanto maior a eficiência no combate aos incêndios, maior é a concentração dos mesmos na classe I. Apesar de corresponder a apenas 2,4% das ocorrências, os incêndios da classe V ( 200,0 ha) foram responsáveis por 94,5% da área queimada. FOREST FIRE STATISTICS IN BRAZIL FROM 1994 TO 1997 Abstract Forest fire statistics knowledge is an important tool for fire control planning. The objective of this research was to collect information on forest fire occurrence in Brazilian protected areas in the period of 1994 to 1997. The analyzed variables were the number of fires and burned areas per state of the federation, monthly distribution, probable causes, affected vegetation, size class distribution, and average burned area per fire. Results showed that the average burned area per fire was approximately 135 ha and Minas Gerais ranked first, both in number of registered fires (62.7%) and burned surface (25.2%). Incendiary, with 56.6% of the occurrences was the leading cause, followed by debris burning with 22.1%. However, as for the affected area, Debris burning was the leading cause (74.1%), followed by Incendiary (19.8%). The fire season extends from July to November, when 79.2% of the fires occurred, corresponding to 98.6% of the burned surface. Miscellaneous, that includes savanna, secondary growth forest, and grassland were the most affected vegetation type (39.7% of the occurrences). In relation to the burned surface, Native Forest (92.5%) ranked first. The distribution of the registered fires through the size classes presented 23.9% of the occurrences in Class I ( 0.1 ha), whereas 94.5% of the burned area were result of Class V ( 200 ha) fires. Size Class II (0.1 to 4.0 ha), with 49.1% of the occurrences, ranked first in number of registered fires during the analyzed period.

scholarly journals Experimental evidence that parasites drive eco-evolutionary feedbacks

2017 ◽  
Vol 114 (14) ◽  
pp. 3678-3683 ◽  
Author(s):  
Franziska S. Brunner ◽  
Jaime M. Anaya-Rojas ◽  
Blake Matthews ◽  
Christophe Eizaguirre
Keyword(s):  
Gene Expression ◽  
Experimental Evidence ◽  
Body Condition ◽  
Host Resistance ◽  
Expression Profiles ◽  
Juvenile Fish ◽  
Gene Expression Profiles ◽  
Zooplankton Community ◽  
Stream Fish ◽  
Zooplankton Community Structure

Host resistance to parasites is a rapidly evolving trait that can influence how hosts modify ecosystems. Eco-evolutionary feedbacks may develop if the ecosystem effects of host resistance influence selection on subsequent host generations. In a mesocosm experiment, using a recently diverged (<100 generations) pair of lake and stream three-spined sticklebacks, we tested how experimental exposure to a common fish parasite (Gyrodactylus spp.) affects interactions between hosts and their ecosystems in two environmental conditions (low and high nutrients). In both environments, we found that stream sticklebacks were more resistant to Gyrodactylus and had different gene expression profiles than lake sticklebacks. This differential infection led to contrasting effects of sticklebacks on a broad range of ecosystem properties, including zooplankton community structure and nutrient cycling. These ecosystem modifications affected the survival, body condition, and gene expression profiles of a subsequent fish generation. In particular, lake juvenile fish suffered increased mortality in ecosystems previously modified by lake adults, whereas stream fish showed decreased body condition in stream fish-modified ecosystems. Parasites reinforced selection against lake juveniles in lake fish-modified ecosystems, but only under oligotrophic conditions. Overall, our results highlight the overlapping timescales and the interplay of host–parasite and host–ecosystem interactions. We provide experimental evidence that parasites influence host-mediated effects on ecosystems and, thereby, change the likelihood and strength of eco-evolutionary feedbacks.

scholarly journals Soil Microbial Biomass and Community Composition Relates to Poplar Genotypes and Environmental Conditions

Forests ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 262 ◽  
Author(s):  
Leszek Karliński ◽  
Sabine Ravnskov ◽  
Maria Rudawska
Keyword(s):  
Microbial Biomass ◽  
Microbial Communities ◽  
Community Composition ◽  
Soil Depth ◽  
Abiotic Factors ◽  
Soil Conditions ◽  
Main Role ◽  
Site Factors ◽  
Host Genotype ◽  
The Impact

Poplars, known for their diversity, are trees that can develop symbiotic relationships with several groups of microorganisms. The genetic diversity of poplars and different abiotic factors influence the properties of the soil and may shape microbial communities. Our study aimed to analyse the impact of poplar genotype on the biomass and community composition of the microbiome of four poplar genotypes grown under different soil conditions and soil depths. Of the three study sites, established in the mid-1990s, one was near a copper smelter, whereas the two others were situated in unpolluted regions, but were differentiated according to the physicochemical traits of the soil. The whole-cell fatty acid analysis was used to determine the biomass and proportions of gram-positive, gram-negative and actinobacteria, arbuscular fungi (AMF), other soil fungi, and protozoa in the whole microbial community in the soil. The results showed that the biomass of microorganisms and their contributions to the community of organisms in the soil close to poplar roots were determined by both factors: the tree-host genotype and the soil environment. However, each group of microorganisms was influenced by these factors to a different degree. In general, the site effect played the main role in shaping the microbial biomass (excluding actinobacteria), whereas tree genotype determined the proportions of the fungal and bacterial groups in the microbial communities and the proportion of AMF in the fungal community. Bacterial biomass was influenced more by site factors, whereas fungal biomass more by tree genotype. With increasing soil depth, a decrease in the biomass of all microorganisms was observed; however, the proportions of the different microorganisms within the soil profile were the result of interactions between the host genotype and soil conditions. Despite the predominant impact of soil conditions, our results showed the important role of poplar genotype in shaping microorganism communities in the soil.

Zooplankton community composition in Richter Lake, Wisconsin

1984 ◽  
Vol 22 (1) ◽  
pp. 525-532
Author(s):  
John E. Gannon ◽  
Roberta K. Cap ◽  
Kenton M. Stewart ◽  
Wilbur A. Stewart
Keyword(s):  
Community Composition ◽  
Zooplankton Community

scholarly journals Community Composition and Functioning of Denitrifying Bacteria from Adjacent Meadow and Forest Soils

2003 ◽  
Vol 69 (10) ◽  
pp. 5974-5982 ◽  
Author(s):  
J. J. Rich ◽  
R. S. Heichen ◽  
P. J. Bottomley ◽  
K. Cromack ◽  
D. D. Myrold
Keyword(s):  
Community Composition ◽  
Forest Soils ◽  
Vegetation Type ◽  
Denitrifying Bacteria ◽  
Nitrous Oxide Reductase ◽  
Soil C ◽  
Spatial Gradients ◽  
Order Of Magnitude ◽  
Denitrifier Communities ◽  
Dominant Genotype

ABSTRACT We investigated communities of denitrifying bacteria from adjacent meadow and forest soils. Our objectives were to explore spatial gradients in denitrifier communities from meadow to forest, examine whether community composition was related to ecological properties (such as vegetation type and process rates), and determine phylogenetic relationships among denitrifiers. nosZ, a key gene in the denitrification pathway for nitrous oxide reductase, served as a marker for denitrifying bacteria. Denitrifying enzyme activity (DEA) was measured as a proxy for function. Other variables, such as nitrification potential and soil C/N ratio, were also measured. Soil samples were taken along transects that spanned meadow-forest boundaries at two sites in the H. J. Andrews Experimental Forest in the Western Cascade Mountains of Oregon. Results indicated strong functional and structural community differences between the meadow and forest soils. Levels of DEA were an order of magnitude higher in the meadow soils. Denitrifying community composition was related to process rates and vegetation type as determined on the basis of multivariate analyses of nosZ terminal restriction fragment length polymorphism profiles. Denitrifier communities formed distinct groups according to vegetation type and site. Screening 225 nosZ clones yielded 47 unique denitrifying genotypes; the most dominant genotype occurred 31 times, and half the genotypes occurred once. Several dominant and less-dominant denitrifying genotypes were more characteristic of either meadow or forest soils. The majority of nosZ fragments sequenced from meadow or forest soils were most similar to nosZ from the Rhizobiaceae group in α-Proteobacteria species. Denitrifying community composition, as well as environmental factors, may contribute to the variability of denitrification rates in these systems.

scholarly journals The current state of CO2 flux chamber studies in the Arctic tundra

2017 ◽  
Vol 42 (2) ◽  
pp. 162-184 ◽  
Author(s):  
Anna-Maria Virkkala ◽  
Tarmo Virtanen ◽  
Aleksi Lehtonen ◽  
Janne Rinne ◽  
Miska Luoto
Keyword(s):  
Carbon Balance ◽  
Ecosystem Respiration ◽  
Vegetation Type ◽  
Gross Primary Production ◽  
Co2 Flux ◽  
Arctic Tundra ◽  
The Arctic ◽  
Environmental Drivers ◽  
Soil Conditions ◽  
Flux Chamber

The Arctic tundra plays an important role in the carbon cycle as it stores 50% of global soil organic carbon reservoirs. The processes (fluxes) regulating these stocks are predicted to change due to direct and indirect effects of climate change. Understanding the current and future carbon balance calls for a summary of the level of knowledge regarding chamber-derived carbon dioxide (CO2) flux studies. Here, we describe progress from recently (2000–2016) published studies of growing-season CO2 flux chamber measurements, namely GPP (gross primary production), ER (ecosystem respiration), and NEE (net ecosystem exchange), in the tundra region. We review the study areas and designs along with the explanatory environmental drivers used. Most of the studies were conducted in Alaska and Fennoscandia, and we stress the need for measuring fluxes in other tundra regions, particularly in more extreme climatic, productivity, and soil conditions. Soil respiration and other greenhouse gas measurements were seldom included in the studies. Although most of the environmental drivers of CO2 fluxes have been relatively well investigated (such as the effect of vegetation type and soil microclimate on fluxes), soil nutrients, other greenhouse gases and disturbance regimes require more research as they might define the future carbon balance. Particular attention should be paid to the effects of shrubification, geomorphology, and other disturbance effects such as fire events, and disease and herbivore outbreaks. An improved conceptual framework and understanding of underlying processes of biosphere–atmosphere CO2 exchange will provide more information on carbon cycling in the tundra.

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