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61.
Damon M. Hall Andrea Feldpausch-Parker Tarla Rai Peterson Jennie C. Stephens Elizabeth J. Wilson 《Sustainability Science》2017,12(3):381-392
Sustainability science is a solution-oriented discipline. Yet, there are few theory-rich discussions about how this orientation structures the efforts of sustainability science. We argue that Niklas Luhmann’s social system theory, which explains how societies communicate problems, conceptualize solutions, and identify pathways towards implementation of solutions, is valuable in explaining the general structure of sustainability science. From Luhmann, we focus on two key concepts. First, his notion of resonance offers us a way to account for how sustainability science has attended and responded to environmental risks. As a product of resonance, we reveal solution-oriented research as the strategic coordination of capacities, resources, and information. Second, Luhmann’s interests in self-organizing processes explain how sustainability science can simultaneously advance multiple innovations. The value logic that supports this multiplicity of self-organizing activities as a recognition that human and natural systems are complex coupled and mutually influencing. To give form to this theoretical framework, we offer case evidence of renewable energy policy formation in Texas. Although the state’s wealth is rooted in a fossil-fuel heritage, Texas generates more electricity from wind than any US state. It is politically antagonistic towards climate-change policy, yet the state’s reception of wind energy technology illustrates how social and environmental systems can be strategically aligned to generate solutions that address diverse needs simultaneously. This case demonstrates that isolating climate change—as politicians do as a separate and discrete problem—is incapable of achieving sustainable solutions, and resonance offers researchers a framework for conceptualizing, designing, and communicating meaningfully integrated actions. 相似文献
62.
63.
The interactions of zebra mussels, invertebrates, fish, and microorganisms were studied experimentally. Trends in the distribution
of total bacterial biomass, the abundance of heterotrophic organisms, and their functional activities in water and grounds
were analyzed. The most favorable conditions for development of bacteria developed in June, in the presence of fish and without
zebra mussels. In experimental ecosystems with zebra mussels, a decrease in the abundance and activity of microorganisms and
a change of dominant yeast forms were observed. 相似文献
64.
The use of quantitative data for constructing prognostic maps of the dynamics of ecosystem degradation and restoration by
nonlinear simulation methods is a topical field of landscape ecology. This method of dynamic cartography is based on fiberwise
comparison of data on the state of Chernye Zemli (the Kalmyk Republic, Russia) in different years and the detailed analysis
of the period on which the prognosis was based. For this purpose, materials of repeated aerial and satellite photography obtained
during a long period (1954–1993) were used. Comparison of maps characterizing the dynamics of Chernye Zemli between 1958 and
1993 allows prognostic electronic maps for the next 10–15 years (with a five-year interval) to be drawn and land prognosis
for the next 20–30 years (1998–2023) to be obtained.
Deceased 相似文献
65.
N. F. Chernousova 《Russian Journal of Ecology》2001,32(2):122-125
The long-term population dynamics of rodent communities in park forests of Yekaterinburg was studied. The results showed that deep population depressions occurring in natural communities are not characteristic of the urban communities. In the urban environment, the density of rodents is always maintained at a relatively high level due to the appearance of species that are atypical for the natural communities. This fact deserves attention in view of the increasing risk of tick-borne encephalitis (TBE) in the region, as a high rodent abundance may provide for the maintenance of a stable TBE focus in the city. 相似文献
66.
Distributions of heavy metals in the surface sediments of the Gulf of Saros, NE Aegean Sea 总被引:1,自引:0,他引:1
The Gulf of Saros in the northeastern Aegean Sea (Turkey) is a relatively unpolluted marine environment. There is almost no industry and only small settlements in the surrounding region. The main sources of fresh water and sediment to the Gulf are the Meric River in the northwest and the Kavak Creek in the east. It has an asymmetric bathymetry with a 10-km-wide shelf to the north and up to 15-km-wide, 700-m-deep trough in the south. Water circulation in the Gulf is characterized by longshore currents and anticyclonic eddies. The Black Sea waters, leaving the Sea of Marmara through the Canakkale Strait, are known to enter the southern Gulf during the summer. The surface sediments on the northern shelf consist mainly of sand, whereas those on the slope and the deep trough are mainly silt and clay. The ranges of Fe, Mn, Cu, Zn, Pb, Ni, and Hg contents of the surface sediments from the Gulf of Saros are 0.25 4.60%, 114 1740 ppm, 6-44 ppm, 23-154 ppm, 2-80 ppm, 14-145 ppm, and 10-130 ppb, respectively. These values are low compared to those from the other neighboring marine environments, indicating the pristine nature of the Gulf in terms of metal pollution. However, most metal and organic carbon (Corg) distributions in the Gulf sediments show the effect of anthropogenic and natural inputs to the northwestern and eastern shelf areas from the Meric River and the Kavak Creek and to the deep trough from the Black Sea waters. 相似文献
67.
Emerald, north-east Queensland, is at the northern margin of the wheat cropping region of Australia. The Emerald region was previously used predominantly for grazing beef cattle; however, cropping has developed in importance over the past 30 years. We use historical climate records (1890-1998) to simulate and compare wheat yields, grass production and live-weight gain (LWG) over time. The cropping expansion from the 1970s to the early 1990s has occurred in a unique period in the 108-year record with the highest average wheat yields, lowest wheat yield variability and the greatest relative productivity of wheat production against grass production. If this window of opportunity is a result of long-term climate variability, then cropping is likely to decline in the region as conditions return to those experienced earlier in the record. If this increase is related to climate change, then cropping is likely to persist in the region with productivity maintained at current levels particularly through the yield-enhancing effects of increased atmospheric CO2 concentrations. However, this persistence will be influenced by the frequencies of El Ni?o conditions that may increase with global warming. The high relative productivities experienced over the past few decades have probably biased producers' expectations, and applications for drought support need to take into account the longer-term perspective provided by this analysis. Nevertheless, the last 6 years have the lowest simulated mean LWG production on the record. The identification of poor production periods depended on the production element being addressed and the timescale involved. 相似文献
68.
69.
Assessment of environmental changes in the Orinoco River delta 总被引:1,自引:0,他引:1
H. Echezuría J. Córdova M. González V. González J. Méndez C. Yanes 《Regional Environmental Change》2002,3(1-3):20-35
Major anthropogenic driven changes in the hydrologic and sedimentation patterns of the Orinoco River have had an impact on
environmental conditions in the delta. The abrupt water flow reduction from 3,600 to 200 m3 s–1 in one of its major distributaries resulting from dam construction forced its transformation from a fresh-water body into
a tidal channel with an increase in salinity level (as far as 100 km upstream) and with well-mixed water at the mouth and
estuarine connection to the Paria Gulf. Three different sectors along this distributary can be identified (indicated by the
Na/Cl ratio in the water). As a result, noticeable changes have occurred in the mangrove community which moved about 60 km
further upstream. The changes have also promoted the formation of new islands of sediment progradation at the mouth of this
distributary, where successional colonization and species replacement by different species of grasses and mangroves take place.
Electronic Publication 相似文献
70.
Baranchikov Yu. N. Perevoznikova V. D. Vishnyakova Z. V. 《Russian Journal of Ecology》2002,33(6):398-401
In the southern-taiga low grass–green moss fir forest completely defoliated by the Siberian moth, the rate of soil respiration in the third year after the pest population outbreak was 1.5 times higher than in an undisturbed tree stand. This was explained by a significant increase in the abundance and activity of soil microorganisms in the pest-defoliated forest, which occurred due to the qualitative changes in the litter composition and the increased temperature and moisture in the upper soil layers. The rate of carbon emission from the soil in the defoliated forest was 41.7 kg/ha per day, compared to 28.3 kg/ha per day in the undisturbed fir forest. 相似文献