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871.
Richard Grossman 《Environment, Development and Sustainability》2012,14(6):973-977
Human population growth challenges efforts toward sustainability. People who are concerned about the environment, development, and sustainability are in a position to stress the importance of human population and to encourage people to choose small family size (Grossman, in Conserv Biol, 24(6), pp 1435–1436, 2010). Nevertheless, this vital subject has been treated infrequently in this journal. Of more than 500 articles published since its inception, only 15 have touched on human population, few have had population as a primary subject and only three have suggested that readers of this journal can and should have influence over population growth. This article concludes by suggesting ways that we who are concerned about sustainability should promote education about family planning and the advantages of small family size. 相似文献
872.
To restore food security to a traditional African cropping system following a sudden loss of seed, genetic diversity must be re-established. This study examines the extent to which Cowpea diversity was reinstated two years after a flood disaster in Gaza Province, Mozambique. The contribution that seed from various sources made to the recovery was assessed using semi-structured interviews and morphological and molecular data. Data suggest that diversity had recovered to some extent yet there was evidence of a narrowing of the genetic base, with fewer rare alleles and differences in the distribution of allele frequencies. Although the main channels for accessing seed after the flood were seed relief and markets, these sources contributed to minimal and different diversity. It appears that diversity was regained primarily through social networking in the form of loans or gifts of seed from friends and relatives. The results of the study are discussed in relation to seed relief approaches. 相似文献
873.
E. Yu. Zakharova 《Russian Journal of Ecology》2012,43(2):162-168
Phenotypic variation in the widespread Siberian and Mongolian butterfly species Coenonympha amaryllis (Stoll, 1782), an indicator of undisturbed steppe communities, is analyzed. It is shown that its size variation is influenced
by a complex of climatic factors, the most important of them being the average starting date of the frost-free period and
average annual temperature in the region. Longitude-dependent variation in size is described by a “sawtooth curve” characteristic
of species with changing voltinism. 相似文献
874.
The current state of the ecology of the impact regions is outlined. It is argued that the complex of ecosystems situated around
a point polluter (an impact region) is an appropriate model for solving several fundamental and applied ecological problems
related to the exploration of strong external impacts on biota. Typical methodological errors resulting from insufficient
attention to specific features of passive experiments are analysed, and ways to avoid them are proposed. The principles of
spatial arrangements of study sites within the impact region and of the selection of experimental and evaluation units are
discussed. 相似文献
875.
G. N. Tikhonova I. A. Tikhonov E. V. Kotenkova A. I. Munteanu I. G. Uspenskaya Yu. N. Konovalov V. I. Burlaku V. F. Kiku S. D. Georgitsa N. K. Karaman V. B. Nistreanu A. N. Mal’tsev 《Russian Journal of Ecology》2012,43(3):236-242
Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses. 相似文献
876.
Integrated studies on the temperature regime in a limestone outcrop area have been performed, including analysis of the latitudinal trends and dynamics of direct solar radiation input onto slopes of different exposures and the redistribution of temperatures depending on mesotopographic features of the slopes. Assessment of the diversity of ecological conditions in this model landscape has shown that about 3.3% of its area is potentially suitable for the formation of a relict lithophytic floristic assemblage. 相似文献
877.
D. C. Mccune Leonard H. Weinstein Jay S. Jacobson A. E. Hitchcock 《Journal of the Air & Waste Management Association (1995)》2013,63(11):465-468
Leaves of Tendergreen bean plants exposed to atmospheric fluoride concentrations in the range 1.7 to 7.6 μg/m3 showed increased levels of enolase and catalase activity and decreased levels of pyruvate and α-ketoglutarate. Phosphoenolpyruvate carboxylase activity and oxalacetate were not affected. The leaves of Milo maize plants exposed to 5.0 μg F/m3 showed increased levels of enolase and pyruvate kinase activity and a decreased level of pyruvate. Oxalacetate and α-ketoglutarate levels were not affected. Catalase activity was increased, then decreased by IIF fumigation. The changes induced by HF were greatest six to 10 days after the start of fumigation and disappeared or decreased in magnitude during the post-fumigation period. 相似文献
878.
C. E. Barthel JR. 《Journal of the Air & Waste Management Association (1995)》2013,63(11):475-478
This is a report on Meetings of Representatives of National Air Pollution Preventions Associations to Consider the Establishment of an International Union, held in Washington, D. C, June 18–19, 1964 and Houston, Texas, June 21–22, 1964. 相似文献
879.
880.
An addition of additives to fuel oils prior to combustion is one way of reducing combustible contaminant emissions to the outer air. Reported test results show that some additives improve, moderately, the combustive properties of fuel oils. Combustion is also improved but to a lesser degree, in boiler systems that are deficient in operation and design. Being combustible, polynuclear hydrocarbons emissions would be reduced by use of additives. Other types of additives to reduce slagging and inhibit corrosion from combustion of fuel oils are also available. The cost of using additives is low. Improved additives are required, especially ones to better combustion in the deficient boiler systems. These can be found by research and literature surveys. Their effectiveness and nontoxicity would be confirmed by laboratory and field testing. 相似文献