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101.
The Arctic is undergoing biological and environmental changes, and a coordinated effort to monitor is critical to detect these changes. The Circumpolar Biodiversity Monitoring Programme (CBMP) of the Arctic Council biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF), has developed pan-Arctic biodiversity monitoring plans that aims to improve the ability to detect and report on long-term changes. Whilst introducing this special issue, this paper also presents the making of the terrestrial monitoring plan and discusses how the plan follows the steps required for an adaptive and ecosystem-based monitoring programme. In this article, we discuss how data on key findings can be used to inform circumpolar and global assessments, including the State of the Arctic Terrestrial Biodiversity Report, which will be the first terrestrial assessment made by the CBMP. Key findings, advice for future monitoring and lessons learned will be used in planning next steps of pan-Arctic coordinated monitoring.  相似文献   
102.
Climate-induced changes in vegetation phenology at northern latitudes are still poorly understood. Continued monitoring and research are therefore needed to improve the understanding of abiotic drivers. Here we used 14 years of time lapse imagery and climate data from high-Arctic Northeast Greenland to assess the seasonal response of a dwarf shrub heath, grassland, and fen, to inter-annual variation in snow-cover, soil moisture, and air and soil temperatures. A late snow melt and start of growing season is counterbalanced by a fast greenup and a tendency to higher peak greenness values. Snow water equivalents and soil moisture explained up to 77 % of growing season duration and senescence phase, highlighting that water availability is a prominent driver in the heath site, rather than temperatures. We found a significant advance in the start of spring by 10 days and in the end of fall by 11 days, resulting in an unchanged growing season length. Vegetation greenness, derived from the imagery, was correlated to primary productivity, showing that the imagery holds valuable information on vegetation productivity.  相似文献   
103.
104.
Five sorption materials were studied with a focus on polishing pretreated stormwater: crushed limestone, shell-sand, zeolite, and two granulates of olivine. These materials are commercially available at comparatively low cost and have been subjected to a minimum of modification from their natural states. The sorbents were tested for phosphorus, arsenic, cadmium, chromium, copper, nickel, lead, and zinc at concentration and conditions relevant for typical stormwater. The materials were tested for sorption capacity and kinetics. Desorption was tested under neutral and alkaline conditions and in the presence of chloride. For most sorbent/sorbate combinations, significant sorption occurred within the first minutes of contact between sorbent and sorbate. Treatment to the low microgram per liter range could be achieved by contact times of less than 1 hour. The study indicated that sorption filters can be designed for long life expectancy at comparatively low cost by applying the materials tested.  相似文献   
105.
Stocking Atlantic salmon Salmo salar L. in the Meuse river system is unsuccessful, since hardly any adults return upstream. To investigate problems during seaward migration, individual salmon smolts were tracked in the Dutch part of the river Meuse, using the Nedap Trail® system. The study included a comparison for two seasons, one with high (2010) and one with low (2011) discharge conditions. Cultivated smolts (Loire-Allier strain, n = 100 per year) were implanted with telemetry tags and released in the tributary Roer in March, at the beginning of the natural smolt run. The study area was split into four river sections each characterized by different conditions: tributary Roer, main river Meuse extensively dammed, main river Meuse free flowing and the estuary. Mortalities differed considerably between sections. In the free flowing river Meuse the mortalities were relatively low (10 and 25 %). Mortalities were high in the tributary (44 and 45 %), the dammed river (46 and 49 %) and in the estuary (89 and 90 %). Only 2 and 3 % of the smolts escaped into the North Sea. Results are discussed in relation to environmental factors light and discharge and the presence of man-made obstacles: weirs, hydropower plants and a sea lock. A lack of current and delays at man-made obstacles result in disorientation of fish, a higher risk of predation and disturbance of the smolt run timing. Mortality causes must decrease for sustaining a salmon population in the Meuse.  相似文献   
106.
Effects of mussel dredging on sediment metabolism (oxygen uptake and sulfate reduction rates) and phosphorus dynamics (flux across sediment-water interface and sequential extraction) were examined in Limfjorden (Denmark) during spring (May) and summer (August). Sediment samples were taken during mussel dredging and in addition an experimental simulation of the dredging was performed to investigate short-term changes in phosphorus (P) dynamics. Iron-bound P was reduced by up to 2/3 in the surface layer in the dredging track (from 31 to 8?mmol?P?m?2), whereas the dissolved P-pools and less reactive particulate pools were not affected by dredging. Sediment oxygen consumption was enhanced immediately after dredging, but returned to the initial level after 4 days (20–40?mmol?m?2?d?1). The enhanced consumption was attributed to reoxidation of reduced compounds released during dredging. Sulfate reduction rates were high in the area (13–15?mmol?m?2?d?1) and sulfides competed with P for oxidized iron resulting in low iron-bound pools in the area (<4% of total P pools). Sulfate reduction rates were stimulated by the resuspension of sediments, especially in August, where a subsurface maximum was found, possibly due to a mixing of labile organic matter into these layers. In contrast sulfate reduction rates were reduced in the dredging track due to removal of labile organic matter from the surface layers. The loss of P during dredging was to some extent counteracted by regeneration of iron-bound P pools in the surface layers. The release of P due to mussel dredging was estimated to be in the same order of magnitude as the annual loading from the catchments and point sources to Limfjorden.  相似文献   
107.
Summary. Insects feeding on Cruciferae recognize their host plants at least partially by means of specific responses to glucosinolates. However, the effects of variations in glucosinolate levels on the acceptability of plants for specialized insects are not well understood. A survey of the literature demonstrated positive, no, as well as negative correlations between plant acceptability and glucosinolate levels. The present study took advantage of the presence of transgenic Arabidopsis thaliana plants with increased glucosinolate levels. Transgenic A. thaliana contain the CYP79A1 gene from Sorghum bicolor. This gene encodes an enzyme which converts L-tyrosine into p-hydroxyphenylacetaldoxime in the biosynthesis of cyanogenic glycosides in S. bicolor. In transgenic A. thaliana plants, endogenous enzymes convert p-hydroxyphenylacetaldoxime into p-hydroxybenzylglucosinolate (sinalbin), which is not found naturally in this plant. The introduction of CYP79A1 resulted in a four-fold increase in total glucosinolate levels in transgenic A. thaliana plants. Although these changes in glucosinolate levels were rather dramatic, they did not have any effects on the acceptability of A. thaliana for the two flea beetle species, Phyllotreta nemorum and P. cruciferae. The flea beetles did not discriminate between transgenic and wildtype plants. Furthermore, they did not discriminate between leaf discs of wildtype plants where different concentrations of p-hydroxybenzylglucosinolate had been applied topically on the leaf surface. Feeding in P. nemorum was stimulated by extremely high levels of allylglucosinolate while this compound had no effect on P. cruciferae. It is concluded that the effect of glucosinolates on adapted insects depends on the chemical or physical environment in which the glucosinolates are found.  相似文献   
108.
Ehrich  Dorothée  Schmidt  Niels M.  Gauthier  Gilles  Alisauskas  Ray  Angerbjörn  Anders  Clark  Karin  Ecke  Frauke  Eide  Nina E.  Framstad  Erik  Frandsen  Jay  Franke  Alastair  Gilg  Olivier  Giroux  Marie-Andrée  Henttonen  Heikki  Hörnfeldt  Birger  Ims  Rolf A.  Kataev  Gennadiy D.  Kharitonov  Sergey P.  Killengreen  Siw T.  Krebs  Charles J.  Lanctot  Richard B.  Lecomte  Nicolas  Menyushina  Irina E.  Morris  Douglas W.  Morrisson  Guy  Oksanen  Lauri  Oksanen  Tarja  Olofsson  Johan  Pokrovsky  Ivan G.  Popov  Igor Yu.  Reid  Donald  Roth  James D.  Saalfeld  Sarah T.  Samelius  Gustaf  Sittler  Benoit  Sleptsov  Sergey M.  Smith  Paul A.  Sokolov  Aleksandr A.  Sokolova  Natalya A.  Soloviev  Mikhail Y.  Solovyeva  Diana V. 《Ambio》2020,49(3):801-804
Ambio - In the original published article, some of the symbols in figure 1A were modified incorrectly during the typesetting and publication process. The correct version of the figure is provided...  相似文献   
109.
Ambio - This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to...  相似文献   
110.
Denmark has committed itself to the European 2010 target to halt the loss of biodiversity. Currently, Denmark is in the process of designating larger areas as national parks, and 7 areas (of a possible 32 larger nature areas) have been selected for pilot projects to test the feasibility of establishing national parks. In this article, we first evaluate the effectiveness of the a priori network of national parks proposed through expert and political consensus versus a network chosen specifically for biodiversity through quantitative analysis. Second, we analyze the potential synergy between preserving biodiversity in terms of species representation and recreational values in selecting a network of national parks. We use the actual distribution of 973 species within these 32 areas and 4 quantitative measures of recreational value. Our results show that the 7 pilot project areas are not significantly more effective in representing species than expected by chance and that considerably more efficient networks can be selected. Moreover, it is possible to select more-effective networks of areas that combine high representation of species with high ranking in terms of recreational values. Therefore, our findings suggest possible synergies between outdoor recreation and biodiversity conservation when selecting networks of national parks. Overall, this Danish case illustrates that data-driven analysis can not only provide valuable information to guide the decision-making process of designating national parks, but it can also be a means to identify solutions that simultaneously fulfill several goals (biodiversity preservation and recreational values).  相似文献   
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