Fate of glyphosate in soil and the possibility of leaching to ground and surface waters: a review   总被引：3，自引：0，他引：3  

Borggaard OK  Gimsing AL 《Pest management science》2008,64(4):441-456

The very wide use of glyphosate to control weeds in agricultural, silvicultural and urban areas throughout the world requires that special attention be paid to its possible transport from terrestrial to aquatic environments. The aim of this review is to present and discuss the state of knowledge on sorption, degradation and leachability of glyphosate in soils. Difficulties of drawing clear and unambiguous conclusions because of strong soil dependency and limited conclusive investigations are pointed out. Nevertheless, the risk of ground and surface water pollution by glyphosate seems limited because of sorption onto variable-charge soil minerals, e.g. aluminium and iron oxides, and because of microbial degradation. Although sorption and degradation are affected by many factors that might be expected to affect glyphosate mobility in soils, glyphosate leaching seems mainly determined by soil structure and rainfall. Limited leaching has been observed in non-structured sandy soils, while subsurface leaching to drainage systems was observed in a structured soil with preferential flow in macropores, but only when high rainfall followed glyphosate application. Glyphosate in drainage water runs into surface waters but not necessarily to groundwater because it may be sorbed and degraded in deeper soil layers before reaching the groundwater. Although the transport of glyphosate from land to water environments seems very limited, knowledge about subsurface leaching and surface runoff of glyphosate as well as the importance of this transport as related to ground and surface water quality is scarce.  相似文献   

Anaesthesia of farmed fish: implications for welfare   总被引：1，自引：0，他引：1  

Zahl IH  Samuelsen O  Kiessling A 《Fish physiology and biochemistry》2012,38(1):201-218

During their life cycle as farmed animals, there are several situations in which fish are subjected to handling and confinement. Netting, weighing, sorting, vaccination, transport and, at the end, slaughter are frequent events under farming conditions. As research subjects, fish may also undergo surgical procedures that range from tagging, sampling and small incisions to invasive procedures. In these situations, treatment with anaesthetic agents may be necessary in order to ensure the welfare of the fish. The main objective of this paper is to review our knowledge of the effects of anaesthetic agents in farmed fish and their possible implications for welfare. As wide variations in response to anaesthesia have been observed both between and within species, special attention has been paid to the importance of secondary factors such as body weight, water temperature and acute stress. In this review, we have limited ourselves to the anaesthetic agents such as benzocaine, metacaine (MS-222), metomidate hydrochloride, isoeugenol, 2-phenoxyethanol and quinaldine. Anaesthetic protocols of fish usually refer to one single agent, whereas protocols of human and veterinary medicine cover combinations of several drugs, each contributing to the effects needed in the anaesthesia. As stress prior to anaesthesia may result in abnormal reactions, pre-anaesthetic sedation is regularly used in order to reduce or avoid stress and is an integral part of the veterinary protocols of higher vertebrates. Furthermore, the anaesthetic agents that are used in order to obtain general anaesthesia are combined with analgesic agents that target nociception. The increased use of such combinations in fish is therefore included as a special section. Anaesthetic agents are widely used to avoid stress during various farming procedures. While several studies report that anaesthetics are effective in reducing the stress associated with confinement and handling, there are indications that anaesthesia may in itself induce a stress response, measured by elevated levels of cortisol. MS-222 has been reported to elicit high cortisol release rates immediately following exposure, while benzocaine causes a bimodal response. Metomidate has an inhibitory effect on cortisol in fish and seems to induce the lowest release of cortisol of the agents reported in the literature. Compared to what is observed following severe stressors such as handling and confinement, the amount of cortisol released in response to anaesthesia appears to be low but may represent an extra load under otherwise stressful circumstances. Furthermore, anaesthetics may cause secondary adverse reactions such as acidosis and osmotic stress due to respiratory arrest and insufficient exchange of gas and ions between the blood and the water. All in all, anaesthetics may reduce stress and thereby improve welfare but can also have unwanted side effects that reduce the welfare of the fish and should therefore always be used with caution. Finally, on the basis of the data reported in the literature and our own experience, we recommend that anaesthetic protocols should always be tested on a few fish under prevailing conditions in order to ensure an adequate depth of anaesthesia. This recommendation applies whether a single agent or a combination of agents is used, although it appears that protocols comprising combinations of agents provide wider safety margins. The analgesic effects of currently used agents, in spite of their proven local effects, are currently being debated as the agents are administrated to fish via inhalation rather than locally at the target site. We therefore recommend that all protocols of procedures requiring general anaesthesia should be complemented by administration of agents with analgesic effect at the site of tissue trauma.  相似文献   

Estimation of biomass change in montane forests in Norway along a 1200 km latitudinal gradient using airborne laser scanning: a comparison of direct and indirect prediction of change under a model-based inferential approach     

Ole Martin Bollandsås  Liviu Theodor Ene  Terje Gobakken  Erik Næsset 《Scandinavian Journal of Forest Research》2018,33(2):155-165

The current study compared two approaches for estimating change of aboveground biomass (AGB) in montane forests in Norway using field- and remotely sensed data from airborne laser scanning (ALS) from two points in time (four-year interval). The first was an indirect method that involved modeling and prediction of AGB at two points in time using ALS metrics as predictors, estimating the change from differences between AGB predictions. The second was a direct method, where change was modeled and predicted directly using differences between corresponding ALS metrics derived at the two measurement occasions as predictors, and the estimate was based on the predicted differences. Both methods were applied over a 1500?km long and 250?m wide transect from south to north in Norway comprising 250?m² grid cells. The results showed that the indirect method was more precise than the direct method. The indirect method estimated 0.65?Mg?ha^?1 change in AGB over the observation period, with a corresponding 95% confidence interval of ±0.27?Mg?ha^?1. The corresponding figures for the direct method was 0.54 and ±0.51?Mg?ha^?1. The direct method has been recommended previously. We conclude that the indirect method is both more precise and versatile.  相似文献   

Provenance variation in Christmas tree characteristics in subalpine fir (Abies lasiocarpa) planted in Denmark and Iceland     

Brynjar Skulason  Ole Kim Hansen  Ulrik Braüner Nielsen 《Scandinavian Journal of Forest Research》2018,33(3):222-232

A field test with 26 provenances of subalpine fir and corkbark fir was established at three sites in Denmark and one site in Iceland in 1999. Survival, growth and Christmas tree quality were assessed after 10 growing seasons in Denmark and 12 in Iceland. Provenances showed significant differences for all measured traits. The western-most subalpine fir provenances from Washington state and British Columbia showed the overall best results in Denmark with the highest survival (after 15 years), fastest growth in height and highest Christmas tree quality and profitability as well as both good postharvest needle retention and high resistance to pests. The corkbark fir provenances also showed high Christmas tree quality and the lowest frequency of fork formation, but corkbark fir provenances also exhibited the poorest postharvest needle retention. In Iceland, the corkbark fir provenances generally showed the highest survival rate and Christmas tree quality. The White River provenance from British Columbia is recommended for use in Denmark. The Mount Taylor provenance from the Cibola National Forest in New Mexico is recommended for use in Iceland.  相似文献   

Consequences of an Improved Road Network in Rural Iran: Does it Lead to Better Livelihoods and Forest Protection?     

Arezoo Soltani  Prem L. Sankhayan  Ole Hofstad  Farshid Eshraghi  Abbas Arabmazar 《Small-Scale Forestry》2017,16(3):347-365

Construction of new roads in rural areas is closely linked to market accessibility and economic growth. It also leads to exploitation of natural resources that may accelerate deforestation. These conflicting effects of an improved road network on rural development and depletion of forest resources present a serious challenge to policy makers interested in sustainable development. This paper investigates the effects of road networks on biological and socio-economic behaviour. The analysis was conducted by using a non-linear bio-economic model for a community in southern Zagros, Iran where they manage the adjoining forest according to traditional rules. Data for the model were obtained through village surveys and published resources. The model followed a holistic approach by incorporating a number of livelihood activities, such as, crop cultivation, goat husbandry, charcoal production and hiring out of community labour, along with several logical resource constraints. It was run over a period of 45 years. The results showed that new roads can either fuel forest degradation or contribute to forest protection depending on the choice of policy options. The study concludes that construction of new roads should be accompanied by policies aimed at higher state controls over newly accessible forest areas through regulatory measures, creation of new non-farm employment opportunities and strengthening of traditional institutions through providing extension services for local communities and facilitating NGO involvement so as to minimize the adverse effects on forest resources.  相似文献   

The effects of isoflurane minimum alveolar concentration on withdrawal reflex activity evoked by repeated transcutaneous electrical stimulation in ponies     

Claudia Spadavecchia  Olivier Levionnois  Peter Kronen  Ole K. Andersen 《Veterinary journal (London, England : 1997)》2010,183(3):337-344

The aim of this study was to quantify the effects of isoflurane at approximately the minimum alveolar concentration (peri-MAC) on the temporal summation (TS) of reflex activity in ponies. TS was evoked by repeated electrical stimulations applied at 5 Hz for 2 s on the digital nerve of the left forelimb of seven ponies. Surface electromyographic activity was recorded from the deltoid and common digital extensor muscles. TS thresholds and amplitude of response to stimulations of increasing intensities were assessed during anaesthesia at 0.85, 0.95 and 1.05 times the individual MAC, and after anaesthesia in standing animals. Under isoflurane anaesthesia, TS thresholds increased significantly in a concentration-dependent fashion and at each isoflurane MAC, the responses increased significantly for increasing stimulation intensities. A concentration-dependent depression of evoked reflexes with a reduction in the slopes of the stimulus–response function was observed for both muscles. The results demonstrated that with this model it is possible to describe and quantify the effects of anaesthetics on spinal sensory-motor processing in ponies.  相似文献   

ISAFRUIT:The total chain approach     

Dr. Ole Callesen 《The Journal of Horticultural Science and Biotechnology》2013,88(6)

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Composition of characteristic soils on the raised atoll Bellona,Solomon Islands     

Ole K. Borggaard  Christian Bender Koch  Bo Elberling  Henrik Breuning-Madsen  Lars Stemmerik 《Geoderma》2012

Knowledge is scarce about the composition of soils on Bellona and other Pacific atolls. Such knowledge is important as it is closely related to sustainable land use of these special soils formed on carbonatic/phosphatic materials. Therefore, the micromorphological, chemical and mineralogical composition of samples from genetic horizons in three dominant Bellonese soils (Malanga, Kenge Ungi and Kenge Toaha) and underlying rock (Tanahu) were investigated. Tanahu mainly consists of dolomite, but this mineral is absent in the three soils, which are dominated by phosphate-containing minerals. The Malanga soil is strongly dominated by Ca and P with minor amounts of Al, F and Fe present in fluorapatite, hydroxyapatite and crandallite. In contrast, Al, Fe and P dominate in the Kenge Ungi and Kenge Toaha soils in accordance with a mineralogy consisting of crandallite together with aluminum oxides (gibbsite/boehmite) and iron oxides, mainly goethite with minor contents of hematite. The observed carbonate for phosphate substitution in the apatites and crandallite is important as it indicates an increased phosphate availability in the soils. All three soil samples contain ≤ 1% Si and very little K and Mg. Total contents of essential microelements are considered adequate, but the rather high contents of Sr and U, especially in the Kenge Ungi soil may be problematic. Although the composition of the soils suggests substantial fertility and resilience, the lack of K-containing weatherable minerals (silicate minerals) is in line with a very low K (and low Mg) content and explains why fertilization may be needed to sustain future cultivation of these special soils. Due to a possible low bioavailability of Fe, Mn and maybe other micronutrients at the circumneutral pH of these carbonatic/phosphatic soils as well as the rather high contents of Sr and U, it may be recommended to test element availability using appropriate chemical soil tests supplemented by plant experiments to ensure safe and sustainable (optimal) soil use. However, according to the local farmers, the Malanga, Kenge Toaha and Kenge Ungi soils are considered well suited for production of the preferred crops.  相似文献   

Clinical utility,dose determination,and safety of ocular contrast‐enhanced ultrasonography in horses: A pilot study     

Klaas‐Ole Blohm  Alexander Tichy  Barbara Nell 《Veterinary ophthalmology》2020,23(2):331-340

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Determination of Total Ammonium Nitrogen in Pig and Cattle Slurry: Sample Preparation and Analysis     

Sven G. Sommer  Viggo Kjellerup  Ole Kristjansen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):146-151

Abstract

In order to supply the correct amount of ammonium to the crop when slurry is spread on the field, it is necessary to know the ammonium concentration. Slurry is a heterogeneous substance and there is a risk that organic N-compounds and the ionic strength will interfere with the determination of ammonium. The usability of five different methods for the determination of ammonium in solution has been tested on 18 different cattle and pig slurries and compared to a manual distillation titration technique. Colorimetric determination using an autoanalyzer and an automatic titration distillation device using MgO were highly accurate, and the precision was close to 1%. Distillation with NaOH caused interference from hydrolysable organic compounds. An ammonium electrode could be used, but the accuracy was not good. When using the automatic titration distillation device, samples should immediately be transferred to Kjeldahl flasks with water or acidified to prevent loss of volatile ammonia, unless they are to be distilled within 30 min.  相似文献