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51.
52.
Water-level change is integral to the structure and function of Great Lakes coastal wetlands, and many studies document predictable relationships between vegetation and water level. However, anthropogenic stressors, such as invasive species, land-use change, and water-level stabilization, interact to shift the historical cycle (of native vegetation migration up- and down-slope) toward dominance by invasive Typha species. Knowing from earlier studies that water-level stabilization alters the historical vegetation cycle, we asked if similar shifts can occur where water levels are not stabilized. Using historical aerial photographs of three coastal wetlands (in Lake Michigan's Green Bay, Wisconsin), we determined that habitat dominated by Typha species has expanded to eliminate wet meadow habitat. Between 1974 and 1992, linear regressions showed strong, significant relationships of both meadow area (R2 ≥ 0.894; p < 0.02) and marsh area (R2 ≥ 0.784; p < 0.05) to water level in all three wetlands. In 2000, meadow area was below that predicted by the historical pattern due to the landward advance of marsh habitat during a year of decreasing water levels. In the same period, land use in the wetland watersheds converted from agriculture to urban. Urbanization and the replacement of native Typha latifolia by the invasive hybrid Typha xglauca may have overwhelmed the beneficial impact of water-level fluctuation. The documentation of vegetation shifts, as herein, is an essential step in the process of preserving and restoring ecological integrity.  相似文献   
53.
Because of undesirable side effects of chemical methods pulsed underwater corona discharges are emerging as a potential future advanced oxidation process (AOP) for water disinfection. In pulsed corona discharges a discharge channel is created, which contains a non-thermal plasma with a low degree of ionisation and low electron densities, but with electron energies of up to 10 eV. It has been demonstrated that electrons with this energy can dissociate water and oxygen molecules and produce various reactive radicals (*OH, H*, O*, HO2*), molecular species (H2O2, H2, O2), ultraviolet radiation and shock waves. It is supposed that the combination of all effects leads to a very efficient killing of microorganisms. To understand this in detail and to improve the efficiency of the overall system there is the need to develop suitable diagnostic methods for the quantitative determination of the various oxidants produced during the discharge. In this paper we present preliminary experimental results obtained with different chemical probes for *OH radicals, and H2O2 produced by pulsed corona discharges.  相似文献   
54.
Power Technology and Engineering - Advanced methods for determining the hydrological and geomorphological characteristics of torrential pools, which are important for the design of reliable and...  相似文献   
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56.
Banks were substantially deregulated during the 1980s. This altered the cost-minimizing mix between deposit interest payments and operating expenses (capital and labor for branch convenience and free deposit services). Measured bank output was relatively unaffected by these changes. The proportion of deposits receiving higher interest rates increased more rapidly than factor quantities were reduced, so unit deposit costs rose. Consumers benefited, but the measured net effects for banks were negative, averaging –0.8% to –1.4% a year in net technical change from 1977 to 1988. These influences were measured three different ways and for both equilibrium and disequilibrium factor input specifications. All three approaches—a standard time trend, a time-specific index, and shifts in cross-sectional cost functions—gave consistent results. The results were robust whether measured at the banking firm or branch office level or on the cost frontier.  相似文献   
57.
Book Reviews     
Richard Robison, Indonesia: The Rise of Capital, Allen and Unwin, Sydney, 1986 pp. xxv + 425. Indexed. $19.95.

W.L. Korthals Altes, Changing Economy in Indonesia: Volume 7: Balance of Payments, 1822–1939, Amsterdam: The Royal Tropical Institute. pp. 167.

Trade Statistics, Java, 1823–73: Trade Statistics, Indonesia 1874–1937. Mededeelingen van het Centraal Kantoor voor de Statistiek nos 160 and 161

Om Prakash, The Dutch East India Company and the Economy of Bengal, 1630–1720, Princeton: Princeton University Press, 1985 pp. xii + 291, map, tables. graphs, glossary, index. Cloth $38.50.

Sediono M.P. Tjondronegoro, Social Organization and Planned Development in Rural Java, Singapore, Oxford University Press for the Institute of Southeast Asian Studies, 1984, pp. xv + 326.

A. Fujimoto and F. Matsuda (eds), An Economic Study of Rice Farming in West Java, Tokyo: NODAI Research Institute, Tokyo, University of Agriculture, 1986.

A. Fujimoto and T. Matsuda (eds), A Comparative Study of the Structure of Rice Productivity and Rural Society in Southeast Asta Two Village Studies in Indonesta and Thailand, Tokyo: University of Agriculture, 1985. Reviewed by C.L J. van der Meer (1986) Bulletin of Indanesian Economic Studies, 22(2) pp. 124–27

David Jenkins, Suharto and His Generals: Indonesian Military Politics, 1975–1983, Ithaca: Cornell Modern Indonesia Project, Monograph Series No. 64, 1984, pp. xiii + 280. US$12.50. David Bourchier, Dynamics of Dissent in Indonesia Sawito and the Phantom Coup, Ithaca: Cornell Modern Indonesia Project, Interim Reports Series, 1984, pp. 128. US$9.00.

Linda G. Martin (ed), The ASEAN Success Story: Social, Economic, and Political Dimensions, East-West Center, distributed by the University of Hawaii Press, Honolulu, 1987, pp. xviii + 253. $15.00.

Mubyarto and Edy Suandy Hamid (eds), Kredit Pedesaan di Indonesia, Badan Penerbit Fakultas Ekonomi, U.G.M., 1986 pp, 160.

Ron Hatley, et al., Other Javas Away from the Kraton, Melbourne: Monash University, 1984, pp. 60.

K.S. Nathan and M. Pathmanathan (eds), Trilateralism in Asia: Problems and Prospects in US-Japan-ASEAN Relations, Antara Book Company, Kuala Lumpur, 1986, pp. xviii + 205. $18.00 (cloth): $12.00 (paper).  相似文献   

58.
This paper discusses the impact of a redistribution of current income from the White to the Black population on the distribution of sectoral output, and total employment by means of a semi‐closed input‐output model.

The results show that a redistribution of current income towards Black households — which no doubt will have positive social and political repercussions — has a non‐negative effect on GDP and a definite positive effect on the performance of sectors with a high private consumption expenditure component, as well as on total employment.  相似文献   

59.
Summary The object of this article is the relation between economic science and the idea of progress in western civilization. That relation can clearly be observed in classical economic theory (influenced by the Enlightment) and the modern theory of growth (Golden Age Economics). The author rejects any identification of economic progress with an unlimited increase of GNP. He proposes a link between the idea of economic progress and the divine mandate of stewardship, which implies that the inter-subjective scarcity of non-renewable resources and environmental factors should constantly be taken into account. He concludes with some remarks about economic growth as a goal of economic policy.

Rede uitgesproken bij de aanvaarding van het ambt van gewoon hoogleraar aan de Vrije Universiteit op 10 maart 1972.  相似文献   
60.
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