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At least 163 records · Page 9Linked to original sources
PubMed2000

The ecological risks and benefits of genetically engineered plants.

Discussions of the environmental risks and benefits of adopting genetically engineered organisms are highly polarized between pro- and anti-biotechnology groups, but the current state of our knowledge is frequently overlooked in this debate. A review of existing scientific literature reveals that key experiments on both the environmental risks and benefits are lacking. The complexity of ecological systems presents considerable challenges for experiments to assess the risks and benefits and inevitable uncertainties of genetically engineered plants. Collectively, existing studies emphasize that these can vary spatially, temporally, and according to the trait and cultivar modified.

Agriculture↗
PubMed2003

Environmental effect of vegetation restoration on degraded ecosystem in low subtropical China.

The environmental effect of degraded ecosystem's vegetation restoration in low subtropical China was studied. Results indicated that the vegetation recovery on degraded lands significantly ameliorates surrounding environment, increases species diversity, improves soil structure, raises soil fertility, enhances productivity, and promotes regional agricultural production and social economic development dramatically. Through the combining engineering and biological measures, the restoration of degraded ecosystem in low subtropical area is possible and economical. The restoration experience in Xiaoliang, Wuhua and other sites are valuable for other degraded subtropical area was introduced.

China↗
PubMed2004

Expanding exergy analysis to account for ecosystem products and services.

Exergy analysis is a thermodynamic approach used for analyzing and improving the efficiency of chemical and thermal processes. It has also been extended for life cycle assessment and sustainability evaluation of industrial products and processes. Although these extensions recognize the importance of capital and labor inputs and environmental impact, most of them ignore the crucial role that ecosystems play in sustaining all industrial activity. Decisions based on approaches that take nature for granted continue to cause significant deterioration in the ability of ecosystems to provide goods and services that are essential for every human activity. Accounting for nature's contribution is also important for determining the impact and sustainablility of industrial activity. In contrast, emergy analysis, a thermodynamic method from systems ecology, does account for ecosystems, but has encountered a lot of resistance and criticism, particularly from economists, physicists, and engineers. This paper expands the engineering concept of Cumulative Exergy Consumption (CEC) analysis to include the contribution of ecosystems, which leads to the concept of Ecological Cumulative Exergy Consumption (ECEC). Practical challenges in computing ECEC for industrial processes are identified and a formal algorithm based on network algebra is proposed. ECEC is shown to be closely related to emergy, and both concepts become equivalent if the analysis boundary, allocation method, and approach for combining global energy inputs are identical. This insight permits combination of the best features of emergy and exergy analysis, and shows that most of the controversial aspects of emergy analysis need not hinder its use for including the exergetic contribution of ecosystems. Examples illustrate the approach and highlight the potential benefits of accounting for nature's contribution to industrial activity.

Algorithms↗
PubMed2005

Novel quantification of coupled natural and cross-sectoral water and nutrient/pollutant flows for environmental management.

Human water use and anthropogenic water pollution and ecosystem deterioration have increased so much that it is now a strategic challenge to maximize benefits from various possible water uses, while ensuring that basic human needs are met and the environment is protected. We propose and develop a novel use of input-output flow analysis as a relatively simple, compact and powerful tool for quantification of coupled natural and cross-sectoral flows of water, nutrients, and pollutants in catchments. The tool quantifies implications of various environmental regulation and management scenarios for both natural water systems and engineered-economic systems and sectors that use and impact natural waters for meeting human needs. Specific case study application to water and nitrogen flows in the Swedish Norrström drainage basin indicates considerable nitrogen load contributions to surface and coastal waters from slow groundwater flow paths and legacies of accumulated nitrogen in subsurface and immobile water pools. This implies that effective nitrogen load abatement cannot focus only on active sources but must also include downstream measures, which can capture and abate nitrogen/pollutant loading from different types of known and yet unknown point and diffuse sources within associated catchments.

Ecosystem↗
PubMed2026

Environmental Release of Genetically Intervened Microorganisms: Towards a New Narrative.

The deliberate release of genetically engineered microorganisms for environmental applications has remained largely blocked since the early days of recombinant DNA technology, when limited ecological knowledge, lack of success stories and public apprehension shaped a culture of caution and restrictive regulation. Despite profound advances in microbial ecology, synthetic biology and genetic design, current frameworks still rely on outdated assumptions and legacy regulations that equate engineered microbes with inherent danger and demand unrealistic forms of absolute containment. This review examines how laboratory-trained microorganisms exist on a continuum with naturally evolved life, and that their risks are neither categorically different nor greater. Rather than pursuing unachievable containment, governance should shift towards traceability, stewardship and long-term monitoring through genomic barcodes, digital twins and transparent oversight. The vision moves from domination and control to care and partnership recognizing engineered microbes as live amendments capable of restoring degraded ecosystems. Achieving this transformation requires new terminology, phased field-trial frameworks, improved scaling methods, and the integration of epistemological perspectives that emphasize reciprocity and coexistence with nature. Reframing biotechnology in this way could finally unlock the capacity of engineered microorganisms to contribute responsibly and effectively to planetary repair in an era of escalating environmental crises.

Microorganisms, Genetically-Modified↗
PubMed2003

Dispelling the myths--biocatalysis in industrial synthesis.

Biocatalysis has emerged as an important tool in the industrial synthesis of bulk chemicals, pharmaceutical and agrochemical intermediates, active pharmaceuticals, and food ingredients. However, the number and diversity of the applications are modest, perhaps in part because of perceived or real limitations of biocatalysts, such as limited enzyme availability, substrate scope, and operational stability. Recent scientific breakthroughs in genomics, directed enzyme evolution, and the exploitation of biodiversity should help to overcome these limitations. As a result, we expect many new industrial applications of biocatalysis to be realized, from single-step enzymatic conversions to customized multistep microbial synthesis by means of metabolic pathway engineering.

Biotechnology↗
PubMed1992

Use of a novel plasmid to monitor the fate of a genetically engineered Pseudomonas putida strain.

Plasmid pSI30 was constructed to increase the sensitivity of detection of a genetically engineered micro-organism (GEM) and its recombinant DNA in environmental samples. This broad host-range, mobilizable plasmid contained chlorocatechol (clc) degradative genes, antibiotic resistance genes (ampicillin and kanamycin) and a fragment of eukaryotic DNA. The clc genes encode enzymes that convert 3-chlorocatechol to maleylacetic acid permitting the host, Pseudomonas putida RC-4, to grow on 3-chlorobenzoate. This catabolic phenotype was exploited using enrichment procedures to detect RC-4(pSI30) cells, free-living in the water column or when irreversibly bound to surfaces. The eukaryotic DNA sequence provided a unique target allowing positive identification by DNA:DNA hybridization. Using the eukaryotic DNA sequence as a probe, no transfer of the plasmid to indigenous bacteria was detected. Persistence of RC-4(pSI30) and its ability to multiply upon addition of 3-chlorobenzoate were demonstrated 78 days after its addition to natural freshwater. In flow-through microcosms RC-4(pSI30), undetectable as free-living cells, was found by enrichment as irreversibly bound sessile forms. These experiments revealed the stability of pSI30 and its utility in a 'combination' detection system for tracking the survival of a GEM and its DNA in environmental samples.

Biodegradation, Environmental↗
PubMed2002

[Complexity of land ecosystem].

In recent years, complexity studies has become a new research region and been widely applied in engineering, biology, economy, management, military, police and sociology. In this paper, from the view of complex science, the main complexity characteristics of land ecosystem were described, furthermore, the application of fractal, chaos, and artificial neural network on the complexity of land ecosystem were also discussed.

Conservation of Natural Resources↗
PubMed1992

Adaptation of model genetically engineered microorganisms to lake water: growth rate enhancements and plasmid loss.

When a genetically engineered microorganism (GEM) is released into a natural ecosystem, its survival, and hence its potential environmental impact, depends on its genetic stability and potential for growth under highly oligotrophic conditions. In this study, we compared plasmid stability and potential for growth on low concentrations of organic nutrients of strains of Pseudomonas putida serving as model GEMs. Plasmid-free and plasmid-bearing (NAH7) prototrophic isogenic strains and two amino-acid auxotrophs, all containing antibiotic resistance markers, were held physically separate from but in chemical contact with lake water containing the natural bacterium-sized microbial populations. Cells were reisolated at intervals over a 2-month period to determine the percent retaining the plasmid and the specific growth rate on various media. Plasmid stability in lake water was strongly strain specific; the NAH7 plasmid was stably maintained by the prototrophic strain for the duration of the test but was lost within 24 h by both of the auxotrophs. Specific growth rates of reisolates, compared with those of the corresponding non-lake water-exposed strains (i.e., parental strains), were not different when measured in rich medium (Luria-Bertani broth). However, specific growth rates were 42, 55, and 63% higher in reisolates of auxotrophs and the plasmid-free prototroph, respectively, when measured in 10-fold-diluted medium after exposure of 15 days or longer to lake water. Moreover, lake water-exposed strains grew actively when reintroduced into sterile lake water (28- to 33-fold increase in numbers over 7 days), while the corresponding unadapted parental strains exhibited no growth over the same period.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Biological↗
PubMed1999

Genetically modified organisms and monitoring.

The genetic modification of organisms for food use has raised serious concern about the potential for adverse effects on the environment, ecosystems and on the health of humans and animals. As a relatively new technology, its impacts remain uncertain but could range from disturbances to the genetic functioning of individual organisms to a reduction in the biodiversity of farmland. As a result, the question of how to monitor for potential impacts is beset with problems. The fact that genetic modification can be used on a range of organisms for a variety of purposes means that those developing monitoring systems will need to be as imaginative as those developing GMOs. In the case of genetically modified organisms (GMOs) for food use, concern has focussed on the transfer of genes to other organisms, the potential for effects on non-target organisms, or on the health of humans and animals, and the likelihood of adverse effects on wildlife due to changes in farming practice. As with other new and unfamiliar technologies, genetic modification is also plagued by the problem of uncertainty. Novel genes are inserted randomly into the genome of the host organisms, and this leads to the possibility of unexpected effects. Unanticipated environmental disasters, such as the concentration of persistent organic pollutants in ecosystems at high latitudes, have highlighted the need for monitoring despite the obvious difficulties inherent in monitoring for unexpected effects.

Agriculture↗