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Book reviews     

Climate change in contrasting river basins: adaptation strategies for water, food and environment. Edited by J Aerts and P Droogers. Published in 2004 by CABI Publishing, 288 p., hardcover. ISBN: 0–85199–835–6. Price: US$100 (orders: services@dadirect.com.au).

Australian water bugs. Their biology and identification (Hemiptera‐Heteroptera, Gerromorpha &; Nepomorpha). By Nils M Andersen? and Tom A Weir. Published in 2004 by CSIRO Publishing/Apollo Books, P.O. Box 1139, Collingwood, VIC 3066, Australia. 344 p., hardcover. ISBN: 0–643–090517. Price: AU$135.00 (orders: publishing.sales@csiro.au).

The Lakes Handbook. Volume I: Limnology and Limnetic Ecology. Volume II: Lake restoration and rehabilitation. Edited by Patrick O'Sullivan and Colin Reynolds. Published by Blackwell Publishing Ltd., 109 Cowley Road, Oxford OX4 1JF, United Kingdom (http//www.blackwellpublishing.com). Volume I (published in 2003) 712 p., hardcover. ISBN: 0632047976. Price: £125. Volume II (published in 2004) 568 p., hardcover. ISBN: 063204795X. Price: £125.  相似文献   
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The T/P altimeter data 1993 – 1997 (cycles 11 – 194) has been analyzed with emphases on seasonal variations in sea surface topography (SST). The amplitude of the annual variations amounted to (5.9±0.3) mm when inverted barometer (IB) corrections were applied and (2.0±0.4) mm without any IB corrections. The amplitude of the semi-annual variations in SST was small with IB corrections applied: (0.6±0.3) mm. However, when no IB corrections were applied, it was (1.8±0.4) mm, i.e. the semiannual variations are at the same level as the annual variations with no IB corrections. The phase angle offset of the annual term has shifted by about 180° when IB correction was applied. The dynamics of the ocean-atmosphere system is discussed and it is concluded that it could, at least partly, be responsible for the above observed effects.  相似文献   
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Legal factors play an underrated but significant role as constraints on conservation management. In this paper, based on observations in both Northern Ireland and the Republic of Ireland, mode of land tenure is assessed to determine its influence on the conservation management of coastal dunes. The tenure types considered are: private ownership, corporate private ownership, tenancy, secured tenancy, leasing, common (joint) ownership, uncertain ownership, public ownership and its subset military ownership. It is suggested that multiple private ownership is least likely to favour effective conservation management. Public ownership by a statutory conservation authority and corporate private ownership by a conservation-orientated NGO are regarded as the optimum tenure types for conservation management of coastal dunes.  相似文献   
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CO2 emissions to the atmosphere were studied in a fertilized sandy agricultural soil with and without a catch crop sown into the main crop. The catch crop was grown primarily with the purpose to decrease N-leaching but this study also wanted to find out if the catch crop could have an effect in a climate change perspective. Plots with catch crop showed decreased CO2 emissions from the soil. Since previous results have shown that catch crops effectively decrease N-leaching we recommend growing catch crops as an effective measure for helping both the climate and the eutrophication issue. Seasonal variations in CO2 emissions were pronounced with maximum emissions from the fertilized agricultural soil in June and from an adjacent unmanaged grassland in August. From the plot with catch crop emissions decreased in July and August but somewhat increased later in the autumn. Fertilized agricultural soil showed a within-soil CO2 sink after harvest, i.e. within-soil CO2 uptake. Availability of NH4+ or NO3- in the soil seems to influence the within-soil CO2 sink, with NH4+ enforcing the sink while the same amount of NO3- instead increased CO2 emissions.  相似文献   
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Agricultural activity is estimated to be responsible for only 6% (8 km) of the total length (135 km) of seriously polluted river channel, but for over 30% (294 km) of the slightly or moderately polluted length (963 km) of channel recorded to date in the state. This article examines the present sources and causes of pollution from agricultural wastes, and speculates on the likely direction of future trends. The most common sources of surface water pollution are animal manures, silage effluent, runoff from land following spreading, and fertilizers.  相似文献   
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