Ecological systems theory, also called development in context or human ecology theory, identifies five environmental systems with which an individual interacts. This theory provides the framework from which community psychologists study the relationships with individuals' contexts within communities and the wider society. Ecological systems theory was developed by Urie Bronfenbrenner. Wikipedia.


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Hellweg S.,Ecological Systems | Canals L.M.I.,Sustainable Consumption and Production
Science | Year: 2014

In the modern economy, international value chains - production, use, and disposal of goods - have global environmental impacts. Life Cycle Assessment (LCA) aims to track these impacts and assess them from a systems perspective, identifying strategies for improvement without burden shifting. We review recent developments in LCA, including existing and emerging applications aimed at supporting environmentally informed decisions in policy-making, product development and procurement, and consumer choices. LCA constitutes a viable screening tool that can pinpoint environmental hotspots in complex value chains, but we also caution that completeness in scope comes at the price of simplifications and uncertainties. Future advances of LCA in enhancing regional detail and accuracy as well as broadening the assessment to economic and social aspects will make it more relevant for producers and consumers alike.


Wagg C.,Ecological Systems | Wagg C.,University of Zürich | Jansa J.,ETH Zurich | Stadler M.,Ecological Systems | And 2 more authors.
Ecology | Year: 2011

There is a great interest in ecology in understanding the role of soil microbial diversity for plant productivity and coexistence. Recent research has shown increases in species richness of mutualistic soil fungi, the arbuscular mycorrhizal fungi (AMF), to be related to increases in aboveground productivity of plant communities. However, the impact of AMF richness on plant-plant interactions has not been determined. Moreover, it is unknown whether species-rich AMF communities can act as insurance to maintain productivity in a fluctuating environment (e.g., upon changing soil conditions). We tested the impact of four different AMF taxa and of AMF diversity (no AMF, single AMF taxa, and all four together) on competitive interactions between the legume Trifolium pratense and the grass Lolium multiflorum grown under two different soil conditions of low and high sand content. We hypothesized that more diverse mutualistic interactions (e.g., when four AMF taxa are present) can ease competitive effects between plants, increase plant growth, and maintain plant productivity across different soil environments. We used quantitative PCR to verify that AMF taxa inoculated at the beginning of the experiment were still present at the end. The presence of AMF reduced the competitive inequality between the two plant species by reducing the growth suppression of the legume by the grass. High AMF richness enhanced the combined biomass production of the two plant species and the yield of the legume, particularly in the more productive soil with low sand content. In the less productive (high sand content) soil, the single most effective AMF had an equally beneficial effect on plant productivity as the mixture of four AMF. Since contributions of single AMF to plant productivity varied between both soils, higher AMF richness would be required to maintain plant productivity in heterogeneous environments. Overall this work shows that AMF diversity promotes plant productivity and that AMF diversity can act as insurance to sustain plant productivity under changing environmental conditions. © 2011 by the Ecological Society of America.


Wagg C.,Ecological Systems | Wagg C.,University of Zürich | Jansa J.,ETH Zurich | Schmid B.,University of Zürich | And 2 more authors.
Ecology Letters | Year: 2011

Soil microbes play key roles in ecosystems, yet the impact of their diversity on plant communities is still poorly understood. Here we demonstrate that the diversity of belowground plant-associated soil fungi promotes plant productivity and plant coexistence. Using additive partitioning of biodiversity effects developed in plant biodiversity studies, we demonstrate that this positive relationship can be driven by complementarity effects among soil fungi in one soil type and by a selection effect resulting from the fungal species that stimulated plant productivity the most in another soil type. Selection and complementarity effects among fungal species contributed to improving plant productivity up to 82% and 85%, respectively, above the average of the respective fungal species monocultures depending on the soil in which they were grown. These results also indicate that belowground diversity may act as insurance for maintaining plant productivity under differing environmental conditions. © 2011 Blackwell Publishing Ltd/CNRS.


Okunev A.O.,Novgorod State University | Verozubova G.A.,Ecological Systems
Journal of Applied Crystallography | Year: 2015

X-ray topography images in the form of contrast rosettes from edge dislocations of the slip system in ZnGeP2 single crystals, obtained under different diffraction conditions, are identified and interpreted. To analyze and model the dislocation images, a semi-phenomenological theory of contrast is applied. The simulation of images of edge dislocations under Borrmann effect conditions was carried out in cases when the diffraction vector was parallel or perpendicular to the slip plane of the dislocation. In both cases, the main part of the experimental image is formed because of waveguiding of Bloch waves in the regions of tension and compression of the lattice on either side of the slip plane. Additional image details arise through relaxation of stresses at the exit surface. Since the color of all lobes of the contrast rosette is related to the sign of the deformation, the location of the dislocation half-plane is unambiguously determined. Thus, from the form of the rosette image, it is possible to obtain the slip plane, the magnitude and sign of the Burger's vector, and the direction of the dislocation line. © International Union of Crystallography 2015.


Kazinski P.O.,Tomsk State University | Shipulya M.A.,Ecological Systems
Annals of Physics | Year: 2011

Rapidly convergent expansions of a one-loop contribution to the partition function of quantum fields with ellipsoid constant-energy surface dispersion law are derived. The omega-potential is naturally decomposed into three parts: the quasiclassical contribution, the contribution from the branch cut of the dispersion law, and the oscillating part. The low- and high-temperature expansions of the quasiclassical part are obtained. An explicit expression and a relation of the contribution from the cut with the Casimir term and vacuum energy are established. The oscillating part is represented in the form of the Chowla-Selberg expansion of the Epstein zeta function. Various resummations of this expansion are considered. The general procedure developed is then applied to two models: massless particles in a box both at zero and nonzero chemical potential, and electrons in a thin metal film. Rapidly convergent expansions of the partition function and average particle number are obtained for these models. In particular, the oscillations of the chemical potential of conduction electrons in graphene and a thin metal film due to a variation of size of the crystal are described. © 2011 Elsevier Inc.


Kharyutkina E.V.,Ecological Systems | Ippolitov I.I.,Ecological Systems | Loginov S.V.,Ecological Systems
Biogeosciences | Year: 2012

The variability of spatial-temporal distribution of temperature and heat balance elements is investigated for the Asian territory of Russia (45-80°N, 60-180°E) using JRA-25, NCEP/DOE AMIP-II reanalysis data and observational data for the period of global warming 1979-2008. It is shown that temperature trend over the territory is 1.4 °C for the period under study according to reanalysis data. Since the beginning of 90s of 20th century the increase of back earth-atmosphere shortwave radiation is observed. Such tendency is in conformity with the cloud cover distribution and downward shortwave radiation at the surface. Regression model describing temperature variability with variability of heat balance elements was presented. We conclude that possible applications for the model include the convenient estimate of temperature variability according to reanalysis data. © Author(s) 2012.


Nevidimova O.,Ecological Systems
11th International Multidisciplinary Scientific Geoconference and EXPO - Modern Management of Mine Producing, Geology and Environmental Protection, SGEM 2011 | Year: 2011

In the article is shown the approach to a research on hydropower resources in Western Siberia. The hydropower potential estimates are based on the following factors: water content of rivers, river slopes and flow velocities. Identified are the portions of rivers with largest energy capacity and the possibility to use hydro potential. A measure of hydrological tension was calculated, which takes into account the quantitative characteristics of following factors: low water, ice effects, high water, sediments runoff (amount of transported sediment), snowmelt runoff intensity. Based on these calculations, the territory was ranked by the degree of hydrological hazards. © SGEM2011 All Rights Reserved by the International Multidisciplinary Scientific GeoConference SGEM.


Nevidimova O.,Ecological Systems
International Multidisciplinary Scientific GeoConference Surveying Geology and Mining Ecology Management, SGEM | Year: 2014

Numerous salt lakes in the forest-steppe zone of Western Siberia can boast with unrivaled biological productivity. They possess a great economical and ecological value, being used for centuries as important sources of water. At the same time, excessive anthropogenic pressure, accompanied by intensive land reclamation works, led to massive destruction of these natural systems. Also, the lakes suffer from natural cause of degradation, due to the change of the territory humidity degree and drainage of wetlands. This change occurred when the moisture reserve, previously allowing all wetland systems to endure dramatic changes in climatic conditions, became extinguished. The paper examines the impact of climate change on the condition of salt lakes, located in the south of Western Siberia, and on their individual components, both in inter-century and intra-century perspectives. The study was based on the analysis of cartographic sources, archived material, statistical analysis of long-term meteorological observations. Individual components, determining the water regimes of lakes, were characterized. The water balance of lakes, the territory humidity dynamics, fluctuations of the lake levels during the past 100 years were considered in detail. Synchrony of climatic periods and hydrological regimes of the lakes were described; the determining influence of atmospheric cyclonic circulation on the periodic variations of lake levels was confirmed. Despite the cyclic nature of lake regimes in the south of Western Siberia, the main trend in their current development is a gradual reduction of the aquatic area and its partition into smaller ponds. © SGEM2014..


Patent
Ecological Systems | Date: 2013-10-25

The present invention relates to an aquaponics system and method. There is provided an aquaponics system including a tank (10) for housing at least one aquatic animal species; a plant growing apparatus (18) for housing one or more plant species growing in an aqueous environment; and a biofilter module including a solids removal means (12) and a biological waste digestion unit (14) including a biological species for digesting solids to produce plant nutrients. Plant nutrients are transferred to the plant growing apparatus (18) and at least a portion of the water is returned to the tank (10).


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