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901.
This study compares diversity and abundance of birds plus abundance of butterflies, bumblebees and herbaceous plants between six small farms (<52 ha arable land) and six large farms (>135 ha arable land) in Roslagen in southeastern Sweden. Two of the large and four of the small farms were organic. Large-scale landscape mosaic and underlying bedrock were similar for all farms. Statistical analysis was performed using box-plots on medians and analysis of variance on mean values. More than twice as many bird species and territories, butterflies, and herbaceous plant species, and five times more bumblebees were found on the small compared to the large farms. The largest differences were found between small organic and large conventional farms. Differences were also noted between small and large organic farms: 56% more bird species were found on small organic than on large organic farms, although none of the farms used any pesticides. We therefore argue that the consideration of organic agriculture's effect on biodiversity should include factors affected by farm size. 相似文献
902.
Sandström P Pahlén TG Edenius L Tømmervik H Hagner O Hemberg L Olsson H Baer K Stenlund T Brandt LG Egberth M 《Ambio》2003,32(8):557-567
When seeking to resolve complex land-management issues, geographical assessment of resources that are in short supply or in dispute can aid the communication of knowledge and the understanding among and between different stakeholders. In this paper, we illustrate how remote sensing and GIS can be used to gather and compile information regarding land-use activities and patterns among reindeer herders and other land users (forestry, mining, tourism, etc) in northern Sweden. The project represents a novel user-oriented effort largely based on the work carried out by the principal end user, i.e. the reindeer herders themselves. The basis for development of land-use plans for reindeer husbandry, was the following: to collect and digitally systemize traditional ecological and landscape knowledge of reindeer habitat use; to integrate this information with results from field inventories and satellite-based vegetation classifications; to map activities of other land users. The resulting land-use plans provide information that can facilitate consultation between the reindeer herders and other stakeholders and can facilitate operational work in reindeer management. This project can serve as a model for participatory involvement and planning, bringing indigenous knowledge and advanced remote-sensing techniques together in an interactive process. 相似文献
903.
Laudon H Poléo AB Vøllestad LA Bishop K 《Environmental pollution (Barking, Essex : 1987)》2005,135(1):121-130
Mortality and physiological responses in brown trout (Salmo trutta) were studied during spring snow melt in six streams in northern Sweden that differed in concentrations of dissolved organic carbon (DOC) and pH declines. Data from these streams were used to create an empirical model for predicting fish responses (mortality and physiological disturbances) in DOC-rich streams using readily accessible water chemistry parameters. The results suggest that fish in these systems can tolerate higher acidity and inorganic aluminium levels than fish in low DOC streams. But even with the relatively low contemporary deposition load, anthropogenic deposition can cause fish mortality in the most acid-sensitive surface waters in northern Sweden during spring flood. However, the results suggests that it is only in streams with high levels of organically complexed aluminium in combination with a natural pH decline to below 5.0 during the spring where current sulphur deposition can cause irreversible damage to brown trout in the region. This study support earlier studies suggesting that DOC has an ameliorating effect on physiological disturbances in humic waters but the study also shows that surviving fish recover physiologically when the water quality returns to less toxic conditions following a toxic high flow period. The physiological response under natural, pre-industrial conditions was also estimated. 相似文献
904.
The concentrations of selected pesticides, of some of their degradation products and nitrophenols in rain were measured at two stations in Denmark in the period January 2000-July 2001. Forty compounds were quantified at least at one station during at least one sampling period. Additionally 17 compounds could be detected but not quantified, and 22 compounds could not be detected at all. The highest depositions of pesticides were observed for pendimethalin and desethylterbuthylazine, which is a degradation product of terbuthylazine. The deposition of the nitrophenols 2,4-dinitrophenol, DNOC, 3-methyl-4-nitrophenol was much higher than that of pesticides. The deposition of 2,4-dinitrophenol was e.g. up to a factor of 40 higher than that of pendimethalin. Atrazine, chloridazon, 2,4-D, dieldrin, disulfoton, fenitrothion, isoproturon, lenacil, metazachlor and propachlor were found in precipitation, although these pesticides are not allowed in Denmark. It can therefore be concluded that they came from abroad and have been transported over at least 60-80 km. For some of these compounds the transport distance is much longer. 相似文献
905.
Wilkins K Bøwadt S Larsen K Sporring S 《Environmental science and pollution research international》2002,9(3):166-168
Although PCB in caulking materials has been forbidden for many years in most of Europe, including Denmark, there has been continued interest to measure PCB levels in the air of contaminated buildings and blood of the occupants (Mengon and Schlatter 1993, Fromme et al. 1996, Ewers et al. 1998, Currado and Harrad 1998, Gabrio et al. 2000). The relatively low priority for investigations of this contamination is probably due to the small quantities inhaled compared to exposure via food, and the rapid metabolism of the most volatile congeners demonstrated by low concentrations of all congeners in the blood of exposed persons (Ewers et al. 1998, Gabrio et al. 2000). There is, however, evidence that PCB containing caulking materials have been used even during the '90s (Fromme et al. 1996). In Denmark, it is estimated that 75 t PCB is still in buildings (Organization of Sealant Branch's Manufacturers and Distributors 2000). During an investigation of dust from buildings with excessive microbial growth (including 35 rooms from 9 buildings), the analysis of semivolatile compounds by thermal desorption-GC/MS of samples from a single building surprisingly revealed large amounts of PCBs containing 3, 4 and 5 chlorine atoms, 10-20 times the amounts found in samples from other buildings. Extraction of the dust by SFE followed by GC/ECD analysis for 12 PCB congeners showed that there was approximately 20 times the total PCB concentrations in dust from the polluted building compared to the levels in the other buildings. Subsequent headspace analysis of caulking material from the polluted building revealed this to be the source. Shelf dust functions as a passive sampling medium and, thus, can be used as a screening method to detect PCB and other semivolatile pollution indoors. 相似文献
906.
907.
Karin Sundberg MD Steen Smidt-Jensen Claes Lundsteen Kirsten Agerbæk John Philip 《黑龙江环境通报》1993,13(12):1101-1110
Due to the low cell concentration, cultures from early amniotic fluid specimens usually require 2–3 weeks in culture prior to karyotyping. The purpose of this study was to evaluate the culture quality of amniotic fluid cells from early pregnancy, obtained by a new filter technique. The hypothetical advantage of the technique was that the increased cell yield might reduce the culture time before karyotyping. Culture quality was assessed by the number of colonies, the percentage of colonies containing mitoses in filter and control cultures, and the culture time. The setting was a consecutive clinical trial. One hundred samples were obtained from ongoing pregnancies at 11–14 weeks of gestation (mean 12·8 weeks). By circulating a mean of 26 ml of amniotic fluid through a cell filter system leading the cell-free fluid back to the amniotic cavity, the cell yield was increased in the sample of 7 ml corresponding to the dead space of the filter system. The culture results were compared with control cultures from 5 ml samples drawn from the same pregnancies prior to recirculation. The cultures from the first flushing of the filter system yielded 2·6 times more colonies and in total 4·2 times more colonies were found in the three cultures grown from each filter sample when compared with the control cultures. Moreover, the filter cultures showed significantly more colonies with mitoses. The mean culture time was 8·0 days for the filter cultures, from which the karyotypes were analysed. The controls would have needed more time in culture to fulfil the diagnostic criteria for karyotyping. One case of 47,XY, + 21 was found; the rest had normal karyotypes. We conclude that the filter technique improves the culture quality of early amniotic fluid samples and allows early arrest of the cultures. 相似文献
908.
909.
Karl-Gerhardt Børlum 《黑龙江环境通报》1984,4(4):311-314
The Possibility of severe fetal malformations, including neural tube defects, secondary to early amniotic rupture followed by formation of fibrous bands (amniotic band syndrome) is a well-known entitity. The fact that these pregnancies are usually uneventful makes prenatal diagnosis difficult, but routine determination of serum alphafetoprotein, followed by ultrasound scanning, may detect some of the malformations. We present a case, where detection of a neural tube defect led to induced second trimester abortion of a fetus severely affected by this syndrome. There appeared to be a causal relationship between maternal trauma and the amniotic rupture. 相似文献
910.
Dr C. K. Høgdall E. V. S. Høgdall J. Arends B. Nørgaard-Pedersen S. Smidt-Jensen S. O. Larsen 《黑龙江环境通报》1992,12(3):223-227
CA-125, alpha-fetoprotein (AFP), and human chorionic gonadotropin (HCG) were determined in maternal serum in the first trimester from 14 women with a Down's syndrome fetus and 61 women with a healthy fetus. In the second trimester, 15 and 60 serum samples were determined from women with a Down's syndrome and a healthy fetus respectively. In both trimesters, maternal serum CA-125 was found to be elevated in Down's syndrome pregnancies compared with controls. Using discrimination functions, our preliminary results indicate that CA-125 is a better marker than AFP and HCG respectively for a Down's syndrome fetus in the first trimester and improves the detection rate in the second trimester. 相似文献