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21.
Future agriculture with minimized phosphorus losses to waters: Research needs and direction 总被引:3,自引:0,他引:3
Andrew N. Sharpley Lars Bergström Helena Aronsson Marianne Bechmann Carl H. Bolster Katarina Börling Faruk Djodjic Helen P. Jarvie Oscar F. Schoumans Christian Stamm Karin S. Tonderski Barbro Ulén Risto Uusitalo Paul J. A. Withers 《Ambio》2015,44(2):163-179
The series of papers in this issue of AMBIO represent technical presentations made at the 7th International Phosphorus Workshop (IPW7), held in September, 2013 in Uppsala, Sweden. At that meeting, the 150 delegates were involved in round table discussions on major, predetermined themes facing the management of agricultural phosphorus (P) for optimum production goals with minimal water quality impairment. The six themes were (1) P management in a changing world; (2) transport pathways of P from soil to water; (3) monitoring, modeling, and communication; (4) importance of manure and agricultural production systems for P management; (5) identification of appropriate mitigation measures for reduction of P loss; and (6) implementation of mitigation strategies to reduce P loss. This paper details the major challenges and research needs that were identified for each theme and identifies a future roadmap for catchment management that cost-effectively minimizes P loss from agricultural activities. 相似文献
22.
Uusitalo R Turtola E Puustinen M Paasonen-Kivekäs M Uusi-Kämppä J 《Journal of environmental quality》2003,32(6):2007-2016
Runoff P associated with eroded soil is partly solubilized in receiving waters and contributes to eutrophication, but the significance of particulate phosphorus (PP) in the eutrophying P load is debatable. We assessed losses of bioavailable P fractions in field runoff from fine-textured soils (Cryaquepts). Surface runoff at four sites and drain-flow at two of them was sampled. In addition to dissolved molybdate-reactive phosphorus (DRP) losses, two estimates of bioavailable PP losses were made: (i) desorbable PP, assessed by anion exchange resin-extraction (AER-PP) and (ii) redox-sensitive PP, assessed by extraction with bicarbonate and dithionite (BD-PP). Annual losses of BD-PP and AER-PP were derived from the relationships (R2 = 0.77-0.96) between PP and these P forms. Losses of BD-PP in surface runoff (94-1340 g ha(-1)) were typically threefold to fivefold those of DRP (29-510 kg ha(-1)) or AER-PP (13-270 g ha(-1)). Where monitored, drainflow P losses were substantial, at one of the sites even far greater than those via the surface pathway. Typical runoff DRP concentration at the site with the highest Olsen-P status (69-82 mg kg(-1)) was about 10-fold that at the site with the lowest Olsen P (31-45 mg kg(-1)), whereas the difference in AER-PP per mass unit of sediment was only threefold, and that of BD-PP 2.5-fold. Bioavailable P losses were greatly influenced by PP runoff, especially so on soils with a moderate P status that produced runoff with a relatively low DRP concentration. 相似文献
23.
Raimo Virkkala Ari Rajasärkkä Risto A. Väisänen Markku Vickholm Erkki Virolainen 《Conservation biology》1994,8(2):532-544
Protected areas (nature reserves) cover 0.7% of the land area in southern Finland (162,000 km2 ), which belongs to the south- and mid-boreal coniferous forest zones. The value of these areas in preserving land birds was studied on the basis of quantitative censuses. The numbers of bird pairs were estimated in nature reserves and in the whole of southern Finland, and the significance of the reserves was evaluated based on how large a proportion of the total population in southern Finland was found in them. Forest habitat generalists and species of coniferous forests occurred in protected areas as expected by the proportion of these areas in southern Finland. Specimens of these species groups comprise two thirds of all the country's land birds. Species of old-growth forests and open peatlands clearly preferred protected areas, whereas species of bushes, and lush and deciduous forest were scarcer in protected areas than elsewhere in southern Finland. The latter fertile habitats are poorly represented in protected areas, even though due to their disappearance or alteration elsewhere several species confined to these habitats have declined and are even threatened. Drainage of open peatlands and clearcutting of old-growth forests has caused a decrease in the area of these habitats in southern Finland during the past decades. Therefore, protected areas have a high significance in preserving bird species preferring these habitats. Protected areas are particularly important for decreased species of old-growth forests, such as the Three-toed Woodpecker Picoides tridactylus and the Siberian Jay Perisoreus infaustus , as about 10% of their total population in southern Finland was estimated to breed in protected areas. The future protection of both old-growth and deciduous forests is important if we are to preserve bio-diversity of land birds in Finland. 相似文献
24.
Marcus Lindner Tommi Suominen Jordi Garcia-Gonzalo Peter Verweij Risto Päivinen 《Ecological modelling》2010,221(18):2197-2205
Within the forest sector, the sustainability concept has evolved from a narrow focus on sustainable wood production to a much broader evaluation of environmental, social, and economic sustainability for whole value chains. A new software tool - ToSIA - has been developed for assessing sustainability impacts of Forest-Wood-Chains (FWCs). In the approach, FWCs are defined as chains of production processes (e.g. harvesting-transport-industrial processing), which are linked with products (e.g. a timber frame house). Sustainability is determined by analysing environmental, economic, and social sustainability indicators for all the production processes along the FWC. The tool calculates sustainability values as products of the relative indicator values (i.e. indicator value expressed per unit of material flow) multiplied with the material flow entering the process. Calculated sustainability values are then aggregated for the segments of the FWC or for the complete chain. The sustainability impact assessment requires carefully specified system boundaries. ToSIA uses a data-oriented approach that is very flexible in the focus of the analysis and the selection of indicators of sustainability. An example of alternative Norway spruce management systems in Southern Germany and their effects on six sustainability indicators is presented. The less intensive management system with natural regeneration and motor-manual harvesting shows higher carbon storage and slightly less energy use. It creates more employment and higher labour costs, but the average rate of accidents is also higher. ToSIA offers a transparent and consistent methodological framework to assess sustainability impacts in the forest-based sector as affected, e.g. by changes in policies, market conditions, or technology. The paper discusses strengths and limitations of the approach and provides an outlook on further development perspectives of the methodology. 相似文献
25.
Prof.RistoSeppala 《世界环境》2001,(4):44-44,17
此为作者在2001年9月6日全国政协主办的“21世纪论坛——绿色与环保2001”上的发言节选。作者介绍并评价了目前世界上三种有关森林保护的做法。 相似文献
26.
Kimmo P. Suominen Timo Jaakkola Eila Elomaa Risto Hakulinen Mirja S. Salkinoja-Salonen 《Environmental science and pollution research international》1997,4(1):21-30
Sediment accumulation of organic halogen was studied in two forest lakes, one pristine and one which received 30 m3 of biologically purified bleaching wastewater from a kraft pulp mill in 1979 equivalent to ca. 2 kg of adsorbable organic halogen (AOX). Lake sediments were dated with210Pb,134Cs and137Cs and the annual deposition rates of organic halogens and organic matter were calculated. Organic bound halogen contents of the sediment aged 150 years was 180 μg Cl g?1 d.w. in both lakes. The concentration of organic bound halogen at the topmost 6 cm of the sediments (less than 20-years-old) ranged from 45 to 80 μg Cl g?1 d.w. This suggests that solvent extractable halogen had enriched in the older sediment layers. The deposition of extractable organic halogen (EOX) in the lakes in 1950’s was 4 to 5 mg Cl m?2 a?1. Since then, the depositon of EOX doubled in both lakes. The deposition of organic matter increased concomitantly from 50 g m?2 a?1 to 110 g m?2 a?1 in Lake Mustalampi and from 35 g m?2 a?1 to 62 g m?2 a?1 in Lake Pyylampi suggesting that the increase in the deposition of organic halogen followed the increase in the deposition of organic matter. Of the 2 kg of organic halogen discharged into the lake, 5% or less was detected in the sediment in tetrahydrofuran extractable form 15 years later. 相似文献
27.
From data on allozyme, nuclear DNA and mitochondrial DNA markers, we show that the originally North Pacific/Northwest Atlantic mussel Mytilus trossulus is widespread on North European coasts, earliM. trossuluser thought to be inhabited only by Mytilus edulis. Several local occurrences of , interspersed with a dominant M. edulis, were recorded on the North Sea, Norwegian Sea and Barents Sea coasts of Norway and the Barents and White Sea coasts of Kola Peninsula in Russia. The proportion of M. trossulus genetic background observed at any one site varied from 0 to 95%. These new occurrences are not related to the previously known, introgressed M. trossulus population that occupies the Baltic Sea. The new northern occurrences retain both the F and M M. trossulus mitochondria, which have been lost from the Baltic stock. While hybridization takes place wherever M. trossulus and M. edulis meet, the extent of hybrization varies between the different contact areas. Hybrids are rare, and the hybrid zones are bimodal in the northern areas; more interbreeding has taken place further south in Norway, but even there genotypic disequilibria are higher than those in the steep transition zone between the Baltic mussel and M. edulis: there is no evidence of a collapse toward a hybrid swarm unlike in the Baltic. The Barents and White Sea M. trossulus are genetically slightly closer to the NW Atlantic than NE Pacific populations, while the Baltic mussel has unique features distinguishing it from the others. We postulate that the presence of M. trossulus in Northern Europe is a result of repeated independent inter- or transoceanic cryptic invasions of various ages, up to recent times. 相似文献
28.
Juha Sipilä Pertti Auerkari Anna-Mari Heikkilä Risto Tuominen Iris Vela Jyrki Itkonen Mikael Rinne Kalevi Aaltonen 《Journal of Loss Prevention in the Process Industries》2012,25(3):617-622
While the self-heating and spontaneous combustion of coal is a known challenge at coal mines and storage sites, there are known methods for mitigating this challenge for typical open stockpile storage. However, closing the storage will reduce access for corrective action, and it is then important to manage the storage and its transport system with added attention without unduly adding cost or hindering availability. This paper aims to discuss the risk, prevention and extinguishing of fires in closed coal storage facilities, particularly in light of the experience with the Salmisaari underground rock storage facility in Finland. The observed autoignition events have indicated an array of contributing factors, some of which are unique to underground silo storage facilities. On the other hand, many features of the storage facilities can be compared with other extant closed storage systems. The factors affecting fire risk are described and the associated fault and event trees are outlined for autoignition at underground storage. Drawing upon the experiences with past events of self-heating and spontaneous combustion, recommendations are given on cost-effective preventive, corrective and other mitigating action for minimising fire risk and promoting storage availability. 相似文献
29.
Michael Köhl Berthold Traub Risto Päivinen 《Environmental monitoring and assessment》2000,63(2):361-380
Multi-national statistics are frequently based on data, whichoriginate from national surveys. The systems of nomenclatureapplied for key attributes often show national differences.Different error sources which are incorporated in multi-nationalstatistics are discussed. The paper presents approaches forharmonisation and standardisation of multi-nationalenvironmental statistics and gives examples from the forestrysector. The effect of differences of national forest areaestimates on multi-national figures is quantified. An examplefrom forest health surveys is presented that shows the impact ofdifferent interpretation and application of the attribute crown transparency that is already harmonised on theEuropean level. 相似文献
30.
Risto Uusitalo Aaro Närvänen Antti Kaseva Aino Launto-Tiuttu Janne Heikkinen Päivi Joki-Heiskala Kimmo Rasa Tapio Salo 《Ambio》2015,44(2):286-296
Conversion of dissolved P by ferric sulfate into a particulate form sparingly available to algae was studied in 15 ditches in Finland using stand-alone dispensers for ferric sulfate administration. Ferric sulfate typically converted 60–70 % of dissolved P into iron-associated form, a process which required 250–650 kg per kg dissolved P. Mean cost was 160 EUR per kg P converted (range 20–400 EUR kg?1). The costs were lowest at sites characterized by high dissolved P concentrations and small catchment area. At best, the treatment was efficient and cost-effective, but to limit the costs and the risks, ferric sulfate dispensers should only be installed in small critical source areas. 相似文献