ecosystem functions

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Avian ecosystem functions are influenced by small mammal ecosystem engineering

Avian ecosystem functions are influenced by small mammal ecosystem engineering

Invertebrate taxon richness was strongly correlated with total invertebrate abundances across plots. We found that avian granivorous foraging effort, measured either as days to find the food dish, or amount of oats eaten, was not related to the invertebrate prey taxon richness. As expected however, plots that were visited sooner by birds during granivory trials showed signifi- cantly lower invertebrate prey abundances. Consistent with research on omnivorous foraging, we interpret this pattern as resulting from omnivorous birds foraging opportunistically for both grains and invertebrates in the same habitat patches, which in turn depress invertebrate abundance at the most frequently visited foraging sites [30,41]. However, the observed depression in inverte- brate abundances must be due to non-avian as well as avian insectivory. This suggests either that birds are the main insectivores in this community, or that other insec- tivores have similar foraging site preferences. Among strictly insectivorous species, Sturnella loyca tend to for- age off degu colonies in grassland habitats, while Lep- tasthanura aegithaloides, Mimus tenca and Troglodytes musculus forage in trees, which was a significant factor for granivorous foraging as well. Vanellus chilensis are often observed on degu lawns, and Pteroptochos megapodium and Scelorchilus albicolus may nest in degu burrows, all of which are then likely to forage on degu colonies. Although we could not obtain direct evidence of where avian insect- ivorous foraging effort is focused, our data indirectly sug- gest that degus influence insectivorous foraging as well as granivorous foraging, through non-trophic ecosystem en- gineering effects on the plant community [28] and conse- quent provision of favorable invertebrate habitat.
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12 Lee mas

Continental mapping of forest ecosystem functions reveals widespread synergies

Continental mapping of forest ecosystem functions reveals widespread synergies

Van der Plas, F., et al. 2018, "Continental mapping of forest ecosystem functions reveals a high but unrealised potential for forest muntifunctionality", Ecology Letters, vol. 21, no. 1, pp. 31-42, which has been published in final form at https://doi.org/10.1111/ele.12868

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Jack of all trades effects drive biodiversity ecosystem multifunctionality relationships in European forests

Jack of all trades effects drive biodiversity ecosystem multifunctionality relationships in European forests

countries (Spain, Italy, Romania, Poland, Germany and Finland), representing all major European forest types 26 . These contained 15 regionally dominant tree species. As the study aimed to quantify biodiversity effects on ecosystem functioning, plots were selected to differ as much as possible in tree diversity, while minimizing any (co-)variation in other drivers of ecosystem function, including altitude, soil texture, soil pH and species composition and evenness 26 . Hence, although observational, our study aimed to mimic the design of biodiversity experiments by selecting monocultures of all species present in mixed cultures and by having a balanced number of compositions at each level of species richness. However, in contrast to many synthetic community assemblages in experiments, the age structure of the communities is not uniform and the assembly history is unknown. In each plot, tree species richness and 16 ecosystem functions or properties (‘functions’ hereafter), including timber production, decomposition rates, drought and pest resistance and bird diversity, were measured. We quantified multifunctionality as the number of ecosystem functions in a plot with levels exceeding a certain threshold 7 , expressed as a percentage of observed maximum functioning across all plots from the same country. Because the relationship between biodiversity and multifunctionality can depend on the level of functioning required 12,15 , we calculated 99 multifunctionality variables, covering threshold values ranging from 1 to 99% (ref. 12) and using a novel partitioning approach, we quantified the contribu- tions of different mechanisms to biodiversity–multifunctionality relationships. Our results showed that jack-of-all-trades effects cause positive relationships between tree diversity and multifunctionalty when low levels of functioning are required, but negative relationships when very high levels of functioning are desired. Simulation analyses show that in the absence of
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11 Lee mas

The principles of diversity and geographical proximity in an industrial ecosystem: social network analysis in
the Toluca  Lerma region (Principios de diversidad y proximidad geográfica en un ecosistema industrial: Análisis de redes sociales en la región

The principles of diversity and geographical proximity in an industrial ecosystem: social network analysis in the Toluca Lerma region (Principios de diversidad y proximidad geográfica en un ecosistema industrial: Análisis de redes sociales en la región Toluca Lerma

Abstract. Industrial ecology allows the traditional model of industrial activity, where individual manufacturing process that takes raw materials in order to generate products, to be transformed into a more comprehensive model of a regional economy named industrial ecosystem. This ecosystem functions through industrial symbiosis alliances formed by firms that cooperate through the exchange of residues in order to use them as inputs to transform them into valuable products. Moreover, the principles of geographical proximity and diversity of the firms have been found in successful ecosystems in developed countries. This study contributes empirically by using social network analysis (SNA) methods to explore, the presence of these two principles in an industrial ecosystem in the Toluca-Lerma region in Mexico, consisting of 30 firms that have industrial symbiosis alliances. We conclude that in the context of developing countries, the symbiotic exchanges may not be fully explained with the principles of geographical proximity and diversity.
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23 Lee mas

Ecosystem process interactions between central Chilean habitats

Ecosystem process interactions between central Chilean habitats

One possible explanation for these contrasting outcomes is that successionally linked mosaic patches may increase overall functioning within the landscape, while mosaics not linked by a successional pathway may more frequently show decreased functioning as a result of fragmentation (Odum, 1969). By successional, we refer broadly to all endogenous habitat changes, including shifting mosaics, while by non-successional we mean land cover change created and maintained through high levels of disturbance and human niche construction, such as cropland or urban areas. Successional pathways between habitat types imply spatiotemporal dispersal of nutrients, propagules, and/or ecosystem functions at a landscape scale. Thus, when habitat types are linked via successional processes, the functional ‘‘insurance’’ effect of diverse taxon dispersal across landscapes (Loreau et al., 2003) may be facilitated, compared to habitat types not linked by succession. This is because cropland, for example, acts as a successional sink. Ecosystem processes leading to succession, e.g. seed dispersal, may enter cropland but the cropland is either physically inhospitable or maintained through anthropogenic disturbance in a state far from natural succession, until abandonment. While the flux of ecosystem functions across anthropogenically maintained mosaics with cropland, plantations, cities, etc. is of particular interest to conservationists taking an ecosystem services perspective, many semi-natural production systems, such as rangelands, silvopastoralism and agroforestry, can be managed for natural successional mosaics (Fischer et al., 2006).
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13 Lee mas

Integrating the provision of ecosystem services and trawl fisheries for the management of the marine environment

Integrating the provision of ecosystem services and trawl fisheries for the management of the marine environment

In order to adopt an integrated management approach, it is neces- sary to understand community dynamics under stress. To this aim, a functional approach based on Biological Trait Analysis (BTA) has proved useful (Bremner, 2008). Variation in functional components due to stress is linked to changes in BT, which are in turn linked to changes in the species composition (Bremner, 2008). The BTA has also been pro- posed as a useful framework to assess the provision of ecosystem ser- vices by biological communities (Bolam and Eggleton, 2014; Bremner et al., 2006a; Frid, 2011). Ecosystem services depend on functions per- formed by benthic communities (e.g. deep burrowing fauna increase the oxygen fl ow into the sediment, extending the total denitri fi cation zone and stimulating nutrient cycling that is involved in the ecosystem regulating service (Lohrer et al., 2004; Beaumont et al., 2007)). But the estimation of the provision of ecosystem services normally addresses economic or social values (Beaumont et al., 2007; Boyd and Banzhaf, 2007) and rarely focuses on ecological measures (Kremen and Ostfeld, 2005, but see Townsend et al., 2011; Snelgrove et al., 2014). In this con- text, the concept of Ecosystem Service Providers (ESP) was proposed (Kremen and Ostfeld, 2005; Cognetti and Maltagliati, 2010) aiming to encompass a group of organisms sharing particular biological traits (BT) that were related with certain ecosystem functions and, ultimately, with the provision of services. Altogether, these links would determine the dynamics of the ESP; therefore, understanding these links would in- crease our knowledge on the relationships between ecosystem dynam- ics and service delivery.
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Assessing the ability of novel ecosystems to support animal wildlife through analysis of diurnal raptor territoriality

Assessing the ability of novel ecosystems to support animal wildlife through analysis of diurnal raptor territoriality

study area. This contrasts with the fact that plantations usually contain less abundant and diverse potential prey species than native forests [10], as reported for eucalyptus plantations in another region of northern Spain [65]. In the present study, forest areas lie close to agricultural areas (forests and young tree formations cover 50.9% and agricultural areas cover 35.5%), forming a farmland-forest mosaic where hunting options are likely higher than they would be if only forest prey were available. Indeed, Buzzards often hunt in open areas, so forest prey is less important in their diet [47]. At least half the diet of the Goshawks in the study area com- prises prey from non-forest areas, such as the Domestic Pigeon (Columba livia var domestica), Eurasian Collared Dove (Streptopelia decaocto) and the Yellow-legged Gull (Larus michahellis) [46]. In this way, the present novel ecosystem fulfils a structural function, providing suitable habitat to locate the nest and protect offspring within an agricultural matrix that complements the prey range from the forest. These results highlight the importance of landscape-level het- erogeneity for some novel ecosystems [8,66]. Novel ecosystems that increase heterogeneity and complement the functions provided by surrounding areas are more likely to support dense populations of top predators.
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17 Lee mas

Applications of rigged Hilbert spaces in quantum mechanics and signal processing

Applications of rigged Hilbert spaces in quantum mechanics and signal processing

In Subsection II E, we have studied the fractional Fourier transform associated to the Hermite functions. The basic idea of the construction there was that the Hermite functions are eigenfunctions of the ordinary Fourier transform. We would have liked to extend that formalism to the generalized Laguerre functions. This is not possible as M n α ( y ) are not eigenfunctions of the Fourier transform. Nevertheless, we may try to deal with this problem replacing the Fourier transform by some related integral transform. In fact, there exist at least two of these type of transforms for which a decom- position in the spirit of Subsection II E can be done for two exceptional cases corresponding to the values α = ±1/2. Taking into account the relations between Hermite and Laguerre polynomials,
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21 Lee mas

Software Applications Ecosystem for Authority Control

Software Applications Ecosystem for Authority Control

The Semantic Web is not a separate Web but an extension of the current one, in which information is given well-defined meaning, better enabling com- puters and people to work in cooperation [2]. The current work aims to create an applications ecosystem enabling authority control capacities for external appli- cations, by reusing semantically structured data shared by different institutions. This work is structured as follows: a section exposing related work where author- ity control state of the art and specifically AUTHORIS, semantic web, linked open data, Openlink Virtuoso and VIVO are addressed. After that the appli- cations ecosystem is explained in detail, evaluated and we conclude with future steps to follow in order to improve our proposal.
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11 Lee mas

Characterizing quasi metric aggregation functions

Characterizing quasi metric aggregation functions

Taking into account the exposed facts, in this paper we try to take a further step towards the quasi-metric aggregation study. Hence we consider a refinement of the problem studied in Mayor and Valero (2010), and we extend the characterization of metric aggregation functions given by Theorem 1.3 to the framework of quasi-metric spaces. To this end we introduce the notion of quasi-metric aggregation function and we characterize them in terms of triplets. We illustrate, by means of examples, dif- ferences between quasi-metric aggregation functions and the classical ones. Moreover, a complete description of the quasi-metric aggregation functions that preserve quasi- metrics is also given. Furthermore, based on Mayor and Valero (2018), we analyze some properties fulfilled by the functions in matter that will be crucial to discard those functions that cannot be used as quasi-metric aggregation functions. Finally, two possible fields where the developed theory can be useful are exposed.
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20 Lee mas

Mathematical methods in atomic physics = Métodos matemáticos en física atómica

Mathematical methods in atomic physics = Métodos matemáticos en física atómica

Two remarkable features of these functions are their asymptotic behavior, which is proportional to the expected behavior of the scattered wave, and the fact that they can be expressed in closed form. Furthermore, their link with Laguerre-type functions (through the differential equation they satisfy) allowed us to establish very interesting relations and properties; in some cases, when the deduction of a formula was not quite rigorous, the obtained mathematical expressions were numerically validated. Moreover, since Laguerre-type functions can be used to expand any general function, a scattering solution may be approximated by a combination of the proposed Quasi-Sturmian functions. The analyticity of these functions and their properties resulted very helpful to perform analytically different integrals (matrix elements) appearing in scattering problems.
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178 Lee mas

Fatty acids in an estuarine mangrove ecosystem

Fatty acids in an estuarine mangrove ecosystem

Abstract: Fatty acids have been successfully used to trace the transfer of organic matter in coastal and estua- rine food webs. To delineate these web connections, fatty acid profiles were analyzed in species of microbes (Azotobacter vinelandii, and Lactobacillus xylosus), prawns (Metapenaeus monoceros and Macrobrachium rosenbergii) and finfish (Mugil cephalus), that are associated with decomposing leaves of two mangrove species, Rhizophora apiculata and Avicennia marina. The fatty acids, except long chain fatty acids, exhibit changes during decomposition of mangrove leaves with a reduction of saturated fatty acids and an increase of monounsaturated fatty acids. The branched fatty acids are absent in undecomposed mangrove leaves, but present significantly in the decomposed leaves and in prawns and finfish, representing an important source for them. This revealed that the microbes are dominant producers that contribute significantly to the fishes and prawns in the mangrove ecosystem. This work has proved the fatty acid biomarkers as an effective tool for identifying the trophic interactions among dominant producers and consumers in this mangrove. Rev. Biol. Trop. 58 (2): 577-587. Epub 2010 June 02.
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12 Lee mas

Biodiversity and ecosystem processes in tropical ecosystems

Biodiversity and ecosystem processes in tropical ecosystems

estimates of leaf fall, can be used to determine the degree to which plant specíes respond dif­ ferently to climatic variabílity (Worbes and Junk 1989). If they do, the stability of overall ecosystem productivity should be positively correlated with plant species richness, at least at low to moderate species richness. Measure­ ments of rates of increase in stem circumferen­ ces of trees are being used instead of growth rings to estimate ages of trees and rates of wood production (Terborgh et al. 1997c, Lie­ berrnan et al. 1995), but such data can be used to compare growth rates of individual species in relation to variable weather conditions only if individual trees are measured annually or at least every few years. Because gathering those data is technically easy and not particularly ti­ me intensive, such measurements should be pursued vigorously in tropical forests.
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7 Lee mas

Digitally continuous multivalued functions

Digitally continuous multivalued functions

Remark 5. It is easy to see that for N (p) ∩ X as in Remark 4, although p is 4-simple and 8-simple, any single-valued function f : X −→ X \ { p } , such that f (x) = x if x = p, can not be 4-continuous neither 8-continuous, hence Theorema 2 does not hold for Rosenfeld’s digitally continuous functions. Remark 6. There exist in the literature results characterizing simple points in terms of properties of certain inclusion maps, in the spirit of our theorem. For example, in [12] (see [5,6] for further and more recent results) simple surfels (the equivalent for a digital surface X of simple points in the digital plane) are characterized as points x such that the morphism i ∗ : Π 1 n (X \ x) −→ Π 1 n (X ) is
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12 Lee mas

Business mobility: A changing ecosystem

Business mobility: A changing ecosystem

Over the last several years, the pace of mobile innovation has objectively increased, but remarkably little of it actually reaches the broader U.S. mobile user market in a meaningful way [6]. The mobile ecosystem as it currently exists is simply too much of a barrier. Many organizations are currently addressing mobility opportunistically rather than strategically or holistically. Moving to a holistic approach will require members of the business mobility ecosystem to show the IT managers and the business leaders measurable ROI or demonstrate real business value. Without an ROI, IT may not buy in; consequently, without new ways of thinking about revenue splits, there could remain an economic barrier to entry, network coverage may not improve significantly, and usage will likely never move much beyond opportunistic.
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14 Lee mas

On the logic of theory change: incision functions from selection functions

On the logic of theory change: incision functions from selection functions

All these operators have a particular property: every partial meet operator is a kernel operator. Since every partial meet operator is defined in terms of a selection function and every kernel operator is defines in terms of an incision function we study the relation of these functions, giving a a way to define incision functions from selection functions. Moreover, we present some properties for both kinds of functions and their relations.

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Rewilding complex ecosystems

Rewilding complex ecosystems

provides one of the possible pathways towards the vision where “By 2050 biodiversity is valued, conserved, restored and wisely used, maintaining ecosystem services, sustaining a healthy planet and delivering benefits essential for all people" (133). Perhaps innovative policy changes favoring rewilding can add to the current momentum for novel approaches to restoration (19, 134). For instance, Aichi Target 15, which aimed at restoring 15% of degraded ecosystems by 2020, could 5

39 Lee mas

Tourism Revolution Ecosystem

Tourism Revolution Ecosystem

Ya se ha explicado cómo la arquitectura de “ecosistema” es la que define el proyecto TRE. Los diferentes nodos interactúan entre sí y conforman una globalidad donde son varios los ejes en torno a los que se desarrolla el modelo, según se comentó en el capítulo inicial al presentar la gama de servicios que TRE ofrece. La organización se apoya en una serie de sociedades que se agrupan bajo la cabecera de Tourism Revolution Ecosystem S.L. Cada una de ellas se define como un nodo con un sentido propio de acuerdo con los objetivos globales de transformación por acción en el sector del turismo.
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Ramsar COP10 DR 17 Draft Resolution X.17 Environmental Impact Assessment and Strategic Environmental Assessment: updated scientific and technical guidance

Ramsar COP10 DR 17 Draft Resolution X.17 Environmental Impact Assessment and Strategic Environmental Assessment: updated scientific and technical guidance

3. CBD Decision VI/7-A also requested the CBD Executive Secretary to prepare proposals for further development and refinement of the guidelines, in collaboration with relevant organizations, incorporating all stages of environmental impact assessment and strategic environmental assessment processes taking into account the ecosystem approach. In 2004, the CBD Secretariat invited the Netherlands Commission for Environmental Assessment to take the lead in producing revised guidelines on biodiversity-inclusive environmental impact assessment and strategic environmental assessment. The production of the new guidelines involved significant consultation and drew on case study material obtained through the network of the International Association for Impact Assessment. During the production process, the decision was taken to produce separate documents on EIA and SEA. The EIA document contains a refinement of the earlier guidelines and does not substantially deviate from the earlier COP Decision VI/7-A. The SEA guidelines, however, were conceived as a separate new guidance document recognizing the differences in
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47 Lee mas

Hypergeometric functions and binomials

Hypergeometric functions and binomials

There have been two main directions in the study of classical hypergeometric functions. The first of these is to study the properties of a particular series, going back to Euler [Eu1748] and Gauss [Gau1812]. The second one is to find a differential equation satisfied by the hypergeometric function, and to study all the solutions of that equation, going back to Kummer [Kum1836] and Riemann [Rie1857].

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