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71.
E. Smith R. Gordon C. Bourque A. Campbell S. Génermont P. Rochette M. Mkhabela 《Journal of environmental management》2009
A need exists to improve the utilization of manure nutrients by minimizing NH3 emissions from land application of manure. Management strategies to reduce NH3 emissions are available; however, few have been validated under Canadian conditions. A well tested and accurate simulation model, however, can help overcome this challenge by determining appropriate management strategies for a given set of field conditions. 相似文献
72.
Silvina Vargas Gil Analia Becker Claudio Oddino Mónica Zuza Adriana Marinelli Guillermo March 《Environmental management》2009,44(2):378-386
Soil microbial populations can fluctuate in response to environmental changes and, therefore, are often used as biological
indicators of soil quality. Soil chemical and physical parameters can also be used as indicators because they can vary in
response to different management strategies. A long-term field trial was conducted to study the effects of different tillage
systems (NT: no tillage, DH: disc harrow, and MP: moldboard plough), P fertilization (diammonium phosphate), and cattle grazing
(in terms of crop residue consumption) in maize (Zea mays L.), sunflower (Heliantus annuus L.), and soybean (Glycine max L.) on soil biological, chemical, and physical parameters. The field trial was conducted for four crop years (2000/2001,
2001/2002, 2002/2003, and 2003/2004). Soil populations of Actinomycetes, Trichoderma spp., and Gliocladium spp. were 49% higher under conservation tillage systems, in soil amended with diammonium phosphate (DAP) and not previously
grazed. Management practices also influenced soil chemical parameters, especially organic matter content and total N, which
were 10% and 55% higher under NT than under MP. Aggregate stability was 61% higher in NT than in MP, 15% higher in P-fertilized
soil, and also 9% higher in not grazed strips, bulk density being 12% lower in NT systems compared with MP. DAP application
and the absence of grazing also reduced bulk density (3%). Using conservation tillage systems, fertilizing crops with DAP,
and avoiding grazing contribute to soil health preservation and enhanced crop production. 相似文献
73.
Both the Aalborg Commitments and the guidance on integrated urban environmental management and sustainable urban transport
plans proposed by the EU Thematic Strategy on the Urban Environment foresee a baseline review as the first step in developing
integrated urban management plans and systems. A baseline review of urban sustainability undertaken in Riga reveals significant
discrepencies between the sustainability criteria of the Aalborg Commitments and the: responsibilities and competencies of
the municipal government and administration as defined by statutes; policy goals and measures defined in municipal planning
documents; policy goals and measures defined in the Riga Development Plan. To better orient the mandate of the municipality
towards sustainable development, municipal statutes should be supplemented to more fully reflect the issues defined by the
Aalborg Commitments and should include sustainability as a goal. In order to strengthen the implementation of sustainable
development specific policy goals, measures and targets should be formulated for all the Aalborg Commitments issues when revising
existing municipal planning documents or developing a municipal sustainable development management plan. An analysis of the
European Common Indicators and the State of the Environment in Riga 2001 indicators indicates that they can only partially
fulfill a monitoring function for the implementation of the Aalborg Commitments. This highlights a need to better coordinate
sustainable development initiatives at the European level. The methodology used for the baseline review in Riga is useful
for assessing the status of urban sustainability when preparing integrated urban management plans or systems, but requires
testing elsewhere.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
74.
Convergence of Culture, Ecology, and Ethics: Management of Feral Swamp Buffalo in Northern Australia
Glenn Albrecht Clive R. McMahon David M. J. S. Bowman Corey J. A. Bradshaw 《Journal of Agricultural and Environmental Ethics》2009,22(4):361-378
This paper examines the identity of Asian swamp buffalo (Bubalus bubalis) from different value orientations. Buffalo were introduced into Northern (Top End) Australia in the early nineteenth century.
A team of transdisciplinary researchers, including an ethicist, has been engaged in field research on feral buffalo in Arnhem
Land over the past three years. Using historical documents, literature review, field observations, interviews with key informants,
and interaction with the Indigenous land owners, an understanding of the diverse views on the scientific, cultural, and economic
significance of buffalo was obtained. While the diverse stakeholders in buffalo exploitation and management have historically
delivered divergent value orientations on the nature of the human–buffalo relationship, we argue that over time there is the
possibility of values and ethical convergence. Such convergence is possible via transdisciplinary and transcultural agreement
on the value stances that constitute the construction of the being or identity of buffalo in the face of the overwhelming
need to manage population density and gross numbers. 相似文献
75.
76.
The objective of our study was to identify how actors from the main socio-economic sectors perceive their interactions and impacts on a sensitive wetland in an arid climate, specifically the salt pans of Chott Merouane in Algeria. The results revealed that there are three main economic stakes including agriculture, livestock production and salt mining, each activity providing a great benefit for local and national populations. The local population perceived that the current activities are conducted in such a way that they created conflict between socio-economic sectors and caused a threat for long term sustainability of the wetlands. The results highlighted the need to initiate an integrated management approach between the different sectors and to develop a shared vision for the territory. 相似文献
77.
We report observations of disappearance of Erica tetralix in wet heathland, which is unlikely to be caused by competition, as E. tetralix is dying before its place is taken up by other species. To investigate the causes, we used both old and new data. Results showed that presence of Molinia caerulea and Calluna vulgaris were substantial in the former E. tetralix dominated areas. Measurements of the C/N ratio in the morlayer were between 21 and 26 under the E. tetralix stands. As the expected C/N ratio in a healthy nutrient poor ecosystem like the E. tetralix wet heathland is around 30, this indicates that the ratio is probably decreasing and, correspondingly, the probability of nitrogen leaching from the ecosystem is increasing. The morlayer pH was extremely low—between 3.03 and 3.78. This represents a pH decline since the 1960s, where pH values generally were above 4. This supports the hypothesis that the decrease in morlayer pH is the major factor explaining the disappearance of E. tetralix and that measures to increase pH should be considered as part of the recommendations for relevant future management.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-012-0251-z) contains supplementary material, which is available to authorized users. 相似文献78.
Jennifer A. Berger Ritchie Shawn L. Gerstenberger 《Journal of environmental science and health. Part. B》2013,48(7):530-538
In the last decade, the U.S. Food and Drug Administration (FDA) has issued several warnings and recalls for food products that exceed FDA standards for lead. Products containing chili peppers and salt were often suspected as sources of lead contamination, and included items such as candy that are routinely investigated. However, products such as hot sauces that contain similar ingredients have not been the focus of evaluations. This study quantified lead concentrations in imported hot sauces, evaluated product compliance to existing United States standards, and calculated potential dietary lead exposure for children using the Integrated Exposure Uptake Biokinetic Model. Finally, recommendations for reducing the risk of lead exposure from hot sauces are provided. Twenty-five (25) bottles of imported hot sauces manufactured in Mexico and South America were purchased in Clark County, Nevada. All hot sauces were analyzed for lead concentrations, pH, and leaded packaging. Hot sauces were analyzed by inductively coupled plasma mass spectrometry and packaging was analyzed using x-ray fluorescence technology. Four brands of hot sauces (16%) exceeded 0.1 ppm lead, the current FDA action level for lead in candy. Hot sauces with lead concentrations >0.1 ppm lead contained salt and were manufactured in Mexico. Subsequent analysis of additional lots of hot sauces exceeding 0.1 ppm lead revealed inconsistent lead concentrations between and within manufacturer lots. The lead concentrations of the plastic hot sauce lids ranged from below the limit of detection to 2,028 ppm lead. There was no association between lead concentrations in hot sauces and pepper type. These results indicate the need for more rigorous screening protocols for products imported from Mexico, the establishment of an applicable standard for hot sauce, and resources to allow for the enforcement of existing food safety policies. The data reported herein represent the first known investigation of lead concentrations in hot sauces. 相似文献
79.
André Bélanger Charles Vincent Domingos de Oliveira 《Journal of environmental science and health. Part. B》2013,48(5):615-625
Abstract In 1986 strawberry plots were treated with dimethoate, malathion, permethrin and cypermethrin at 80% bloom of primary flowers. In 1987 the plots were sprayed with dimethoate, malathion and permethrin at 30% bloom. Residue analysis of these insecticides on the flowers were analyzed using solvent extraction and gas liquid chromatography. Residue analysis at 0 to 18 days on flowers and fruit showed an exponential decrease. Organophosphates tended to degrade more quickly than synthetic pyrethroids. The results are discussed in the context of an integrated pest management program. 相似文献
80.
Secondary pest outbreak is a counterintuitive ecological backlash of pesticide use in agriculture that takes place with the increase in abundance of a non-targeted pest species after pesticide application against a targeted pest species. Although the phenomenon was well recognized, its alternative causes are seldom considered. Outbreaks of the southern red mite Oligonychus ilicis are frequently reported in Brazilian coffee farms after the application of pyrethroid insecticides against the coffee leaf miner Leucoptera coffeella. Selectivity favoring the red mite against its main predatory mites is generally assumed as the outbreak cause, but this theory has never been tested. Here, we assessed the toxicity (and thus the selectivity) of deltamethrin against both mite species: the southern red mite and its phytoseid predator Amblyseius herbicolus. Additionally, behavioral avoidance and deltamethrin-induced hormesis were also tested as potential causes of red mite outbreak using free-choice behavioral walking bioassays with the predatory mite and life-table experiments with both mite species, respectively. Lethal toxicity bioassays indicated that the predatory mite was slightly more susceptible than its prey (1.5×), but in more robust demographic bioassays, the predator was three times more tolerant to deltamethrin than its prey, indicating that predator susceptibility to deltamethrin is not a cause of the reported outbreaks. The predator did not exhibit behavioral avoidance to deltamethrin; however insecticide-induced hormesis in the red mite led to its high population increase under low doses, which was not observed for the predatory mite. Therefore, deltamethrin-induced hormesis is a likely cause of the reported red mite outbreaks. 相似文献