Landscape heterogeneity

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Landscape heterogeneity drives contrasting concentration–discharge relationships in shale headwater catchments

Landscape heterogeneity drives contrasting concentration–discharge relationships in shale headwater catchments

When the discharge of a stream (Q) increases, concen- trations of solutes (C) can either increase (enrichment be- havior), decrease (dilution behavior), or, perhaps most para- doxically, change very little (chemostasis) (Kirchner, 2003; Godsey et al., 2009; Clow and Mast, 2010). Dilution can result during rainfall events as water stored in a catchment is diluted by less concentrated meteoric water. Enrichment can result if a more concentrated source (e.g., groundwater) mixes with stream water during large rainfall events (Johnson et al., 1969). In contrast, chemostasis cannot be explained by the simple mixing of multiple sources and therefore has been attributed to processes such as chemical reactions with the solid phase along the pathway of water flow (Godsey et al., 2009). Although changing flow paths through soil hori- zons may explain differences in solute response to discharge along hillslope transects (e.g., Bishop et al., 2004), solutes often show different types of behavior in different streams due to landscape heterogeneity, and a unifying explanation for C–Q behavior has remained elusive.

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Frontiers in using LiDAR to Analyze Urban Landscape Heterogeneity.

Frontiers in using LiDAR to Analyze Urban Landscape Heterogeneity.

LiDAR remote sensing is a promising source of structural data with great potential to map, measure, and model the spatial heterogeneity of urban landscapes at both fine and regional scales. LiDAR applications are generally limited to small area due to prohibitive cost and the computational difficulties posed by large data volumes. In this collection of work, I investigated the use of LiDAR data for mapping, measuring, and modeling spatial heterogeneity of urban landscapes at regional scales. In the first study, the fusion of LiDAR digital surface models with Landsat TM imagery was performed to improve accuracy of mapping urban landscape heterogeneity over large regional extents. The second study addressed the use of LiDAR for detecting and mapping the spatial distribution of understory invasive plants in urbanizing forest landscapes. In the final study, I evaluated the effects of LiDAR point density and landscape context on the estimation of aboveground biomass of remnant forests in urbanizing landscapes. The results suggest that leveraging high resolution LiDAR data ‘alone’ and through ‘fusion’ with spectral remote sensing improves assessments of emerging complexities – heterogeneity along urban-rural gradients, understory invasion, and forest biomass – in urban landscapes over large regions.

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Landscape Heterogeneity and Complexity: Implications for Terrestrial Carbon and Water Cycles.

Landscape Heterogeneity and Complexity: Implications for Terrestrial Carbon and Water Cycles.

Landscape heterogeneity and complexity influence multiple aboveground and belowground factors and processes that determine the storage, distribution, and exchange of carbon and water with the atmosphere. Carbon and water dynamics and related processes may vary significantly across the landscape as a function of heterogeneity and complexity, potentially leading to unexpected, emergent ecological behavior. Failure to adequately account for these effects can influence the accuracy of carbon and water cycle models at spatial scales of landscapes and larger. Recent studies highlight risks associated with predicting regional water and carbon fluxes using lumped composite or mosaic approaches, and they provide robust evidence showing that incorporation of local-scale heterogeneities can significantly improve model results. This review highlighted several general ways in which heterogeneity and complexity could be incorporated into models, yet important questions remain: What type of heterogeneity and complexity are more relevant for the carbon and water cycles? At which scale? and how to link the impact of heterogeneity and complexity across spatial and temporal scales? These questions remain to be answered to move the topic forward.

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Neohelice granulata burrow fidelity behaviour related to landscape heterogeneity

Neohelice granulata burrow fidelity behaviour related to landscape heterogeneity

Neohelice granulata provides an interesting animal model for studying behavioural process because it is widely distrib- uted, ensuring variability related to different environmental conditions. The aim of this study was to analyse variation in site fidelity with relation to landscape heterogeneity. Field observations were carried out in three geographically distant marshes in Argentina (Mar Chiquita, San Antonio Oeste, and Riacho San José), which differ in their environ- mental characteristics and where crabs display different reproductive strategies. We analysed potential variation in burrow fidelity with relation to body size, sex and presence of vegetation (mudflat and saltmarsh) at all study sites. In addition, we analysed the influence of tidal flooding on fidelity in the Mar Chiquita saltmarsh. To achieve these goals, we used a mark–recapture method in which we tagged approximately 100 crabs during mid-summer for each zone at each site (a total of 668 crabs) for geographical comparison and approximately 370 crabs to evaluate the influence of tidal flooding. We found more faithful individuals in Mar Chiquita than in San Antonio Oeste and Riacho San José. For the San Antonio Oeste and Riacho San José populations and for Mar Chiquita previous to flooding samples we also found differences in site fidelity related to crab body size. At San Antonio Oeste and Riacho San José the relation- ship between size and proportion of faithful crabs was negative (smaller crabs were more faithful than larger crabs). In Mar Chiquita, a higher proportion of fidelity previous to flooding and a size-dependent response to flooding were detected, suggesting that fidelity may be modulated by tides having different effects on crabs with different body sizes. Equal proportions of males and females displaying site fidelity were observed at all study zones and sites. Our study suggests that N. granulata burrow fidelity behaviour changes with latitude and landscape (mudflat or salt- marsh) and can be sensitive to variables such as body size and frequency of flooding.

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Raccoon Use of Den Trees and Plant Associations in Western Mesophytic Forests: Tree Attributes and Availability or Landscape Heterogeneity?

Raccoon Use of Den Trees and Plant Associations in Western Mesophytic Forests: Tree Attributes and Availability or Landscape Heterogeneity?

Some of the significant variation in this study cannot readily be explained as it does not seem consistent with our understanding of raccoon behavior. Oak/Hickory occurred over nearly 30% of the island, yet received less than 16% use overall. This may in part be due to its availability in the home ranges of individuals that se- lected other portions of the landscape. Regardless, rac- coons were avoiding either Oak/Hickory or the eastern and southern edge of the island. Some raccoons (e.g., adult males) preferred Oak/Hickory during some seasons; others (e.g., juvenile females) were never recorded in Oak/Hickory. We expected more general use of this habitat type, especially during autumn when fruits and nuts typically are an abundant food resource. Mean den- sity of hard and soft fruit-bearing trees >32 cm dbh was 32 stems/ha. Hickories and oaks comprised 76% (24 stems/ha) of the mast-producing trees with red oak (Quercus rubra), white oak (Q. alba) and shagbark hick- ory (Carya ovata) averaging 4.9, 2.3 and 3.4 stems/ha, respectively.

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The Role and Heterogeneity of Visual Pollution on the Quality of Urban Landscape Using GIS; Case Study: Historical Garden in City of Maraqeh

The Role and Heterogeneity of Visual Pollution on the Quality of Urban Landscape Using GIS; Case Study: Historical Garden in City of Maraqeh

The urban landscape heterogeneity has been influenced by the visual, unpleasant and unaccepta- ble face of which there is no charm in it. The present study is formed according to visual pollution and its impact on the appearance and vitality of a city. Preliminary studies and theoretical studies led to the hypothesis with the following themes: 1) There is relationship between the pollution, heterogeneity and visual disturbances urban landscape and urban vitality; 2) Improving the qual- ity, aesthetics and identity of public spaces will increase urban vitality. Therefore, the design process within the theoretical principles, concepts, television and urban landscape, urban art, visual pollution aspects (color, light, and visual symbol) and the quality of urban vitality and ex- plain causal relationships, analytical framework developed and more samples case (garden his- toric town of Maraqeh 1 ) and the area under study were selected using GIS. After designing the

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Characterizing permafrost active layer dynamics and sensitivity to landscape spatial heterogeneity in Alaska

Characterizing permafrost active layer dynamics and sensitivity to landscape spatial heterogeneity in Alaska

estimates of permafrost active layer conditions have relied on detailed ground surveys and measurements from sparse mon- itoring sites (Romanovsky et al., 2010; Osterkamp, 2007). More recent attempts have also incorporated ground-based remote sensing, such as ground-penetrating radar (GPR) and electrical resistivity measurements, but only over limited local extents (Sjöberg et al., 2015; Jorgenson and Grosse, 2016). Several studies have used empirical models driven by in situ ground observations and other geospatial datasets to provide fine-scale (< 100 m resolution) estimates of ac- tive layer and near-surface permafrost conditions (Mishra and Riley, 2014; Pastick et al., 2015). However, the accuracy of these methods is limited by the ability of sparse ground measurements representing landscape heterogeneity, and the resulting empirical models provide only limited insight and mechanistic understanding of underlying processes affecting active layer conditions. Detailed process models have been developed to address the above limitations, while the model accuracy is constrained by a lack of information for effec- tive model parameterization, limited process understanding, and coarse spatial scales of regional drivers (Yi et al., 2015; Jafarov and Schaefer, 2016). Particularly, large uncertainties remain in characterizing regional variability of subsurface soil organic carbon (SOC) content due to limited ground ob- servations of this parameter in the Arctic region (Ping et al., 2008; Burnham and Sletten, 2010) and its effect on ground temperature evolution.

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Disentangling how landscape spatial and temporal heterogeneity affects savanna birds

Disentangling how landscape spatial and temporal heterogeneity affects savanna birds

There is a relatively good understanding of local-scale (1–10 ha) relationships between savanna bird abundance and diversity, and habitat structure, composition and disturbance regimes [22]. However, the interactive effects of spatial and temporal landscape heterogeneity on fauna are often poorly understood (sensu [7]). In the tropical savannas of northeast Australia, Ward and Kutt [11] demonstrated that a precipitation deficit index and remotely- sensed ground cover measured at the site-scale (4 ha) were significant predictors of woodland bird diversity. However, their study did not account for spatial or temporal heterogeneity at the landscape-scale, where anthropogenic disturbances (e.g., clearing, grazing), on top of climatic factors, may have an important influence on vegetation cover and dynamics. There are several unresolved questions regarding how the diversity, distribution and abundance of savanna birds are influenced by broad-scale climatically driven temporal heterogeneity in vegetation cover, and the relative importance of temporal and spatial heterogeneity at the landscape scale driven by management practice.

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Differential responses of cryptic bat species to the urban landscape

Differential responses of cryptic bat species to the urban landscape

We plotted transects using ArcGIS 10 (ESRI Inc 2013) to determine the center point of the 12-point counts within each site. Buffers of 1, 2, and 3 km were created around the central point reflecting the upper limit of home range size for P. pygmaeus and P. pipistrellus (Nicholls and Racey 2006b). We used data from the OS MasterMap Topography Layer (EDINA Digimap Ordnance Survey Service 2013) to reclassify the landscape within each buf- fer into a set of discrete biotope types. These were (1) gray space (buildings, structures, roads, and paths); (2) green space (gardens, parkland, managed grassland, rough grassland, and farmland); (3) inland fresh water; and (4) woodland (coniferous, deciduous, and mixed woodland). A measure of connectivity within the urban landscape, the woodland Euclidean nearest neighbor distance (ENN, the mean value of ENN distances amongst all woodland patches within the landscape) and the Shannon diversity index (SHDI, a measure of landscape heterogeneity) was calculated as previous studies have found these variables to influence bat foraging activity (e.g., Lintott et al. 2014). We calculated the proportion of land covered by each biotope, woodland ENN, and SHDI for each buffer scale using Fragstats v4.0 (McGarigal et al. 2002).

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Transit time heterogeneity in canine small intestine: significance for oxygen transport

Transit time heterogeneity in canine small intestine: significance for oxygen transport

Analysis of blood flow, blood volume, and capillary transit time heterogeneity. Heterogeneity of blood flow among tissue pieces was analyzed separately in mucosa and muscularis/submucosa sections. To permit comparisons among experiments with differing per gram blood flows and tissue weights, the blood flow data were normalized in the following manner: First, fractional tissue weight was calculated for each piece by dividing its weight by the total gut segment weight. Next, the average blood flow over all tissue pieces was computed (ml/ min/kg), and the relative blood flow for each piece determined as the ratio of its flow (ml/min/kg) divided by the average flow. This yielded a dimensionless measure of blood flow in each piece, expressed rela- tive to an average flow of unity. Finally, a graphical frequency distri- bution was constructed for each gut region by summing the fractional weights of tissue pieces in bins according to their relative blood flows. Bin sizes were taken in intervals of 0.2, and a total of z 5,900 tissue pieces were analyzed. This frequency distribution had a mean value of 1.0 and its dispersion indicated how different the blood flows were among tissue pieces, relative to the mean flow for that layer of the gut. Because the computed variables were dimensionless, multiple experiments could be combined to yield a description of the average response.

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A New Landscape Classification Approach for Quantifying Spatial Pattern of Bac Kan Province, Vietnam

A New Landscape Classification Approach for Quantifying Spatial Pattern of Bac Kan Province, Vietnam

Abstract. Landscape theory and its application have played an important role in natural resource exploitation and environmental protection. Various classification approaches had been employed worldwide in landscape ecology studies. This paper had developed a new hierarchical landscape classification framework for quantifying spatial pattern of Bac Kan province. A landscape formation equation was applied with three natural factors (geology, topography, and soil) and cultural factor (land use). A multi-level segmentation technique with multiresolution segmentation algorithm was chosen to segment landscape units (patches) and to categorize landscape types at different levels. The results revealed that the landscape classification of Bac Kan province has 4 hierarchical levels. Level 4, which provided full details of spatial pattern based on geologic period, elevation, soil depth, and land use, had 315 landscape types. At this level, there are 8,427 landscape units mapped with a minimum and maximum areas of 0.02 km 2 and 116.63 km 2 , respectively. A new Bac Kan

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Monitoring of Landscape Transformations within Landscape Parks in Poland in the 21st century

Monitoring of Landscape Transformations within Landscape Parks in Poland in the 21st century

3) Verification of changes in the landscape on the basis of methods used in social sciences. This article proposed to fill a gap in the landscape change research regarding the lack of indicators enabling the easy monitoring of the intensity of landscape transformations. The possibility of using the LCI in reference to the example of landscape parks in the Lower Silesia region in Poland have been verified. Three main methodological challenges have been addressed: 1) the indicator must be simple enough to enable the quick determination of the level of landscape changes during the analyzed period; 2) the indicator must be based on generally available and cyclically published data; and 3) the indicator must be universal enough to be used for different types of areas. The developed landscape change index is based on the assumption that both the loss and increase in the area of each element of land cover causes a change in the landscape. Since the analyses were based mainly on data on land cover, which do not indicate whether changes in landscape affected the way of perceiving it, they were supplemented by individual oral interviews with a group of experts—field workers directly managing and implementing protection tasks in the area of particular landscape parks. In order to fully understand the scope of landscape transformations, the proposed approach combines techniques used in land use change research and social sciences [45]. This is in line with current trends in scientific research in the field of landscape changes [46-48]. Searching for an indicator that will make it possible to evaluate the dynamics of landscape transformations in a simple and quick way is part of the discussion on the methodology of landscape audit [49,50], which is a new landscape management tool in Poland under which all landscape units in the country will be identified and characterized, and one of the characteristics is the dynamics of landscape changes.

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The Trade-Induced Effects of the Services Directive and the Country-of-Origin Principle. CEPS ENEPRI Working Papers No. 44, 24 April 2006

The Trade-Induced Effects of the Services Directive and the Country-of-Origin Principle. CEPS ENEPRI Working Papers No. 44, 24 April 2006

Governments have two basic mechanisms for reducing the costs of regulation heterogeneity for internationally operating firms, namely by regulation harmonisation, or by allowing foreign firms to operate under regulatory standards of their home country (mutual recognition). Harmonisation of regulation is a very long process, and it may not be efficient because countries may have different market preconditions or different regulatory preferences. This means that a wider application of the mutual-recognition principle may be the most auspicious track. Reducing regulation heterogeneity could be done by applying more mutual recognition with regard to qualification standards for service providers. This indeed is the approach that has been chosen by the European Commission in its 'country of origin' principle. It allows for more mutual recognition of regulatory regimes in the European service markets. A service provider that meets the regulatory standards in the member state of origin should no longer be confronted by other or additional regulatory requirements in the EU country where the service is delivered. The country of origin principle (CoOP) applies only in the case of cross-border provision of services without establishment. If a service provider has an establishment, he is entirely subject to the law of that country. A service provider who wants to deliver his services in other Member States without a permanent presence there, has to comply only with the administrative and legal requirements of his country of establishment. Since the CoOP is combined with a number of explicit derogations 13 the individual service provider will have the certainty that outside the derogations he has to comply only with his own law.

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Assesment of urban green space based on landscape ecological principles

Assesment of urban green space based on landscape ecological principles

An ecosystem is the overall interaction between biotic and abiotic factors in a habitat. Biotic factor is the living organisms such as humans, wildlife, plants and microorganisms that live in a habitat and abiotic factor refers to the non-living things such as the soil, water, air or the environment in which they live. Habitat can be defined as a place where organisms live and get all their needs to live. Therefore, urban area is eligible to be considered as an ecosystem too. The study about ecosystem has always been more focused towards natural ecosystem only. The studies on urban ecosystem becoming more frequent in recent years parallel with sustainable development movement. Urban ecological study is very important where interactions between biotic and abiotic factors can be observed and managed according to landscape ecological principles. Although sustainable development encompasses three main components- environment, social and economy can be considered as the components of our ecosystem, the environment component can be considered as the most prominent as its quality affects greatly on the other two components.

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On crossing fitness valleys with the Baldwin Effect

On crossing fitness valleys with the Baldwin Effect

We investigate two variants of how the set of phenotypes produced in an individual’s lifetime are mapped to its fitness: one where individuals have a simple form of phenotypic plasticity (without learning) (CP), and a second where individuals have a learning ability (CP-L). In the CP model, an individual’s fitness is simply the mean of the fitnesses of all of its phenotypes. In the CP-L model, the fitness of an individual is based on that used by Hinton and Nowlan but extended to suit a multiple-peaked landscape. At each lifetime time-step, we allow individuals to exhibit the most fit phenotype found in all time-steps thus far, then take an average of the exhibited phenotypes. As in Hinton and Nowlan’s model, this model of learning represents the ability of an individual to recognise and exploit successful phenotypes when they are discovered. However, ours does not assume that an individual knows it has found the global optimum; thus exploration continues throughout its lifetime.

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Landscape Agroecology: managing interactions between agriculture, nature and socio economy

Landscape Agroecology: managing interactions between agriculture, nature and socio economy

Denmark has been in the forefront in the collection of digital farm data in national databases and in the development of methods to combine these data with other data types (Dalgaard et al. 2002b). In these years, similar data are becoming available in most EU countries e.g. from national censuses, the EUROSTAT Farm Accountancy Data Network (FADN), landscape study site inventory campaigns like the ones initiated in the NitroEurope and the MEA-scope EU research projects, or in less details data available from national area support scheme databases (Petit et al. 2008). Therefore it is interesting to explore the opportunities to develop methods to combine these data, in scenarios for landscape development in the different regions of Europe.

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The Pseudomonas aeruginosa Transcriptional Landscape Is Shaped by Environmental Heterogeneity and Genetic Variation

The Pseudomonas aeruginosa Transcriptional Landscape Is Shaped by Environmental Heterogeneity and Genetic Variation

ABSTRACT Phenotypic variability among bacteria depends on gene expression in response to different environments, and it also reflects differences in genomic structure. In this study, we analyzed transcriptome sequencing (RNA-seq) profiles of 151 Pseu- domonas aeruginosa clinical isolates under standard laboratory conditions and of one P. aeruginosa type strain under 14 differ- ent environmental conditions. Our approach allowed dissection of the impact of the genetic background versus environmental cues on P. aeruginosa gene expression profiles and revealed that phenotypic variation was larger in response to changing envi- ronments than between genomically different isolates. We demonstrate that mutations within the global regulator LasR affect more than one trait (pleiotropy) and that the interaction between mutations (epistasis) shapes the P. aeruginosa phenotypic plasticity landscape. Because of pleiotropic and epistatic effects, average genotype and phenotype measures appeared to be un- correlated in P. aeruginosa.

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xCell: digitally portraying the tissue cellular heterogeneity landscape

xCell: digitally portraying the tissue cellular heterogeneity landscape

At least seven major issues raise concerns that the in silico methods could be prone to errors and cannot reliably portray the cellular heterogeneity of the tumor microenvironment. First, current techniques depend on the expression profiles of purified cell types to identify reference genes and therefore rely heavily on the data source from which the references are inferred and could this be inclined to overfit these data. Second, current methods focus on only a very narrow range of the tumor microenvironment, usually a subset of immune cell types, and thus do not account for the further richness of cell types in the microenvironment, including blood vessels and other different forms of cell subsets [14, 15]. A third problem is the ability of cancer cells to “ imitate ” other cell types by expressing immune-specific genes, such as a macrophage-like expression pattern in tumors with parainflammation [16]; only a few of the methods take this into account. Fourth, the ability of existing methods to estimate cell abundance has not yet been comprehensively validated in mixed samples. Cytometry is a common method for counting cell types in a mixture and, when performed in combination with gene expression profiling, can allow validation of the estima- tions. However, in most studies that included cytometry validation, these analyses were performed on only a very

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Shifting Mosaics in Semi-Steppe Rangelands Driven by Interactive Effect of Human Made Disturbances

Shifting Mosaics in Semi-Steppe Rangelands Driven by Interactive Effect of Human Made Disturbances

Semi-steppe rangelands are a complex, highly dynamic and often multi-layered mosaic of grassland, shrubland, and intermediate communities. A few recent studies have explicitly or implicitly developed synthetic hypotheses about how interactive effects of human made disturbances initiate dynamic changes in plant community composition to cause a shifting mosaic of vegetation pattern across the landscape in rangeland ecosystems, yet to be tested in semi-steppe rangelands. The main goal of this study was to examine a conceptual model of plant community dynamic driven by the interactive effect of grazing and fire in semi-steppe rangelands in West-Iran. The study area includes shrubland, grassland and intermediate plant communities. Several patches within the study area were accidentally burned in 2006, 2008 and 2009. Burned patches were located along a gradient of animal grazing (from light to heavy grazing). We compared plant community composition and animal selections on burned and unburned patches (control) of each plant community. The results showed that if grazing intensity was low, a shift from shrublands to grasslands would be the observed pattern of community dynamics; otherwise with higher level of grazing intensity, change in vegetation structure caused by fire in shrublands was rather transient and this plant community returned to the former state of vegetation four years after the fire. We also observed a higher animal selection on recently burned areas compared to previously burned patches, a pattern that was the resulted of a series of positive and negative feedbacks in forage quality created by selective animal foraging behaviour. The results indicate that the effect of fire on plant community dynamics in semi-steppe rangeland is controlled by grazing intensity and the local changes in plant composition within each community. Both determinants cause a cyclical process of vegetation succession. Vegetation patterns represent the various states of recovery in vegetation and introduces a specific landscape composition in which each scrubland, grassland and intermediate vegetation patch can be described as part of a shifting mosaic process at landscape scale.

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The metabolic signature of small headwater streams:
Natural variability and the response to forestry

The metabolic signature of small headwater streams: Natural variability and the response to forestry

Firstly, in-stream metabolic patch dynamics was examined throughout a calendar year. Small headwater streams displayed very low metabolic rates dominated by heterotrophic processes. Predictable spatial and temporal patterns in population-level, community-level, and whole system-level metabolisms were observed, shaped by temperature, hydrology, and the physical and chemical properties of patches. Secondly, an inundation experiment was conducted to examine metabolic patch dynamics in a small headwater landscape. Inundation resulted in increased metabolic response and a change in the metabolic community profile of the terrestrial patch. It is suggested that regular, above-bank flows are likely to transfer the complexities of in- stream patch dynamics into the terrestrial environment, exemplifying the strong connection between headwater streams and the surrounding landscape.

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