All Stories

  1. Structural and functional characteristics of buffer strip vegetation in an agricultural landscape – high potential for nutrient removal but low potential for plant biodiversity

    Article • The Science of The Total Environment, July 2018, Elsevier

    Professor Brian Kronvang

  2. Going with the flow: Planktonic processing of dissolved organic carbon in streams

    Article • The Science of The Total Environment, June 2018, Elsevier

    Professor Brian Kronvang

  3. Pursuing collective impact: A novel indicator-based approach to assessment of shared measurements when planning for multifunctional land consolidation

    Article • Land Use Policy, April 2018, Elsevier

    Professor Brian Kronvang

  4. A Simplified Nitrogen Assessment in Tagus River Basin: A Management Focused Review

    Article • Water, March 2018, MDPI AG

    Professor Brian Kronvang

  5. Evaluating effects of weed cutting on water level and ecological status in Danish lowland streams

    Article • Freshwater Biology, March 2018, Wiley

    Professor Brian Kronvang

  6. Assessing net-uptake of nitrate and natural dissolved organic matter fractions in a revitalized lowland stream reach

    Article • Limnologica, January 2018, Elsevier

    Professor Brian Kronvang

  7. High-resolution monitoring of nutrients in groundwater and surface waters: process understanding, quantification of loads and concentrations, and management applications

    Article • Hydrology and Earth System Sciences, September 2016, Copernicus GmbH

    Professor Brian Kronvang

  8. The multifunctional roles of vegetated strips around and within agricultural fields. A systematic map protocol

    Article • Environmental Evidence, August 2016, Springer Science + Business Media

    Professor Brian Kronvang

  9. Documenting success stories of management of phosphorus emissions at catchment scale: an example from the pilot river Odense, Denmark

    Article • Water Science & Technology, August 2016, IWA Publishing

    Professor Brian Kronvang

  10. Can controlled drainage control agricultural nutrient emissions? Evidence from a BACI experiment combined with a dual isotope approach

    Article • Hydrology and Earth System Sciences Discussions, July 2016, Copernicus GmbH

    Professor Brian Kronvang

  11. Suspended particles only marginally reduce pyrethroid toxicity to the freshwater invertebrate Gammarus pulex (L.) during pulse exposure

    Article • Ecotoxicology, January 2016, Springer Science + Business Media

    Professor Brian Kronvang

  12. Global effects of agriculture on fluvial dissolved organic matter

    Article • Scientific Reports, November 2015, Nature

    Professor Brian Kronvang

  13. Environmental controls of plant species richness in riparian wetlands: Implications for restoration

    Article • Basic and Applied Ecology, September 2015, Elsevier

    Dr Annette Baattrup-Pedersen, Professor Brian Kronvang

  14. Sources, occurrence and predicted aquatic impact of legacy and contemporary pesticides in streams

    Article • Environmental Pollution, May 2015, Elsevier

    Professor Brian Kronvang

  15. Agriculture and stream water quality – future challenges for monitoring

    Article • Acta Agriculturae Scandinavica Section B - Soil & Plant Science, April 2015, Taylor & Francis

    Professor Brian Kronvang

  16. Policies for agricultural nitrogen management—trends, challenges and prospects for improved efficiency in Denmark

    Article • Environmental Research Letters, November 2014, Institute of Physics Publishing

    Professor Brian Kronvang

  17. Comparison of sampling methodologies for nutrient monitoring in streams: uncertainties, costs and implications for mitigation

    Article • Hydrology and Earth System Sciences Discussions, July 2014, Copernicus GmbH

    Professor Brian Kronvang

  18. Does filter type and pore size influence spectroscopic analysis of freshwater chromophoric DOM composition?

    Article • Limnologica, July 2014, Elsevier

    Professor Brian Kronvang

  19. Linking floodplain hydraulics and sedimentation patterns along a restored river channel: River Odense, Denmark

    Article • Ecological Engineering, May 2014, Elsevier

    Professor Brian Kronvang

  20. Seed germination from deposited sediments during high winter flow in riparian areas

    Article • Ecological Engineering, May 2014, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  21. SWS European Chapter Meeting on wetland restoration—Challenges and opportunities

    Article • Ecological Engineering, May 2014, Elsevier

    Professor Brian Kronvang

  22. Groundwater nitrogen and the distribution of groundwater-dependent vegetation in riparian areas in agricultural catchments

    Article • Ecological Engineering, May 2014, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  23. The River Gelså restoration revisited: Habitat specific assemblages and persistence of the macroinvertebrate community over an 11-year period

    Article • Ecological Engineering, May 2014, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  24. 10 years after the largest river restoration project in Northern Europe: Hydromorphological changes on multiple scales in River Skjern

    Article • Ecological Engineering, May 2014, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  25. Modelling sediment and total phosphorus export from a lowland catchment: comparing sediment routing methods

    Article • Hydrological Processes, February 2014, Wiley

    Professor Brian Kronvang

  26. Mitigation options to reduce phosphorus losses from the agricultural sector and improve surface water quality: A review

    Article • The Science of The Total Environment, January 2014, Elsevier

    Professor Brian Kronvang

  27. Mitigating diffuse pollution from agriculture: International approaches and experience

    Article • The Science of The Total Environment, January 2014, Elsevier

    Professor Brian Kronvang

  28. Comparison of active and passive stream restoration: effects on the physical habitats

    Article • Geografisk Tidsskrift-Danish Journal of Geography, November 2013, Taylor & Francis

    Professor Brian Kronvang

  29. Effects of stream flooding on the distribution and diversity of groundwater‐dependent vegetation in riparian areas

    Article • Freshwater Biology, January 2013, Wiley

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  30. A catchment scale evaluation of multiple stressor effects in headwater streams

    Article • The Science of The Total Environment, January 2013, Elsevier

    Professor Brian Kronvang

  31. Changes in nitrogen loads to estuaries following implementation of governmental action plans in Denmark: A paired catchment and estuary approach for analysing regional responses

    Article • Environmental Science & Policy, December 2012, Elsevier

    Professor Brian Kronvang

  32. Technical Note: Comparison between a direct and the standard, indirect method for dissolved organic nitrogen determination in freshwater environments with high dissolved inorganic nitrogen concentrations

    Article • Biogeosciences, November 2012, Copernicus GmbH

    Professor Brian Kronvang

  33. Recent Climate‐Induced Changes in Freshwaters in Denmark

    Article • November 2012, Wiley

    Professor Brian Kronvang

  34. Interactions between sediments and water: perspectives on the 12th International Association for Sediment Water Science Symposium

    Article • Journal of Soils and Sediments, September 2012, Springer Science + Business Media

    Professor Brian Kronvang

  35. Importance of bank erosion for sediment input, storage and export at the catchment scale

    Article • Journal of Soils and Sediments, September 2012, Springer Science + Business Media

    Professor Brian Kronvang

  36. Low phosphorus release but high nitrogen removal in two restored riparian wetlands inundated with agricultural drainage water

    Article • Ecological Engineering, September 2012, Elsevier

    Professor Brian Kronvang

  37. Threshold values and management options for nutrients in a catchment of a temperate estuary with poor ecological status

    Article • Hydrology and Earth System Sciences, August 2012, Copernicus GmbH

    Professor Brian Kronvang

  38. Effects of a triazole fungicide and a pyrethroid insecticide on the decomposition of leaves in the presence or absence of macroinvertebrate shredders

    Article • Aquatic Toxicology, August 2012, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  39. Species Recruitment following Flooding, Sediment Deposition and Seed Addition in Restored Riparian Areas

    Article • Restoration Ecology, July 2012, Wiley

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  40. Technical Note: Comparison between a direct and the standard, indirect method for dissolved organic nitrogen determination in freshwater environments with high dissolved inorganic nitrogen concentrations

    Article • Biogeosciences Discussions, June 2012, Copernicus GmbH

    Professor Brian Kronvang

  41. Integrated assessment of the impact of chemical stressors on surface water ecosystems

    Article • The Science of The Total Environment, June 2012, Elsevier

    Professor Brian Kronvang

  42. Stream habitat structure influences macroinvertebrate response to pesticides

    Article • Environmental Pollution, May 2012, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  43. Threshold values and management options for nutrients in a catchment of a temperate estuary with poor ecological status

    Article • Hydrology and Earth System Sciences Discussions, February 2012, Copernicus GmbH

    Professor Brian Kronvang

  44. Impacts of pesticides and natural stressors on leaf litter decomposition in agricultural streams

    Article • The Science of The Total Environment, February 2012, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  45. Phosphorus Load to Surface Water from Bank Erosion in a Danish Lowland River Basin

    Article • Journal of Environmental Quality, January 2012, American Society of Agronomy

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  46. Diversity and Distribution of Riparian Plant Communities in Relation to Stream Size and Eutrophication

    Article • Journal of Environmental Quality, January 2012, American Society of Agronomy

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  47. Riparian Buffer Strips as a Multifunctional Management Tool in Agricultural Landscapes: Introduction

    Article • Journal of Environmental Quality, January 2012, American Society of Agronomy

    Professor Brian Kronvang

  48. Dialysis is superior to anion exchange for removal of dissolved inorganic nitrogen from freshwater samples prior to dissolved organic nitrogen determination

    Article • Environmental Chemistry, January 2012, CSIRO Publishing

    Professor Brian Kronvang

  49. Buffer strip width and agricultural pesticide contamination in Danish lowland streams: Implications for stream and riparian management

    Article • Ecological Engineering, December 2011, Elsevier

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  50. Evaluation of nutrient retention in four restored Danish riparian wetlands

    Article • Hydrobiologia, May 2011, Springer Science + Business Media

    Professor Brian Kronvang

  51. Stream characteristics and their implications for the protection of riparian fens and meadows

    Article • Freshwater Biology, April 2011, Wiley

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  52. Local physical habitat quality cloud the effect of predicted pesticide runoff from agricultural land in Danish streams

    Article • Journal of Environmental Monitoring, January 2011, Royal Society of Chemistry

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  53. A distributed modelling system for simulation of monthly runoff and nitrogen sources, loads and sinks for ungauged catchments in Denmark

    Article • Journal of Environmental Monitoring, January 2011, Royal Society of Chemistry

    Professor Brian Kronvang

  54. Climate change effects on nitrogen loading from cultivated catchments in Europe: implications for nitrogen retention, ecological state of lakes and adaptation

    Article • Hydrobiologia, December 2010, Springer Science + Business Media

    Professor Brian Kronvang

  55. Linking monitoring and modelling for river basin management: Danish experience with combating nutrient loadings to the aquatic environment from point and non-point sources

    Article • November 2009, Springer Science + Business Media

    Professor Brian Kronvang

  56. Modelling diffuse nitrogen loadings of ungauged and unmonitored lakes in Denmark: Application of an integrated modelling framework

    Article • International Journal of River Basin Management, September 2009, Taylor & Francis

    Professor Brian Kronvang

  57. Ecological effects of re‐introduction of salmonid spawning gravel in lowland Danish streams

    Article • River Research and Applications, February 2009, Wiley

    Professor Brian Kronvang

  58. Basin characteristics and nutrient losses: the EUROHARP catchment network perspective

    Article • Journal of Environmental Monitoring, January 2009, Royal Society of Chemistry

    Mr Christian Siderius, Dr Panos Panagos, Professor Brian Kronvang

  59. Sediment deposition and net phosphorus retention in a hydraulically restored lowland river floodplain in Denmark: combining field and laboratory experiments

    Article • Marine and Freshwater Research, January 2009, CSIRO Publishing

    Professor Brian Kronvang

  60. International Phosphorus Workshop: Diffuse Phosphorus Loss to Surface Water Bodies—Risk Assessment, Mitigation Options, and Ecological Effects in River Basins

    Article • Journal of Environmental Quality, January 2009, American Society of Agronomy

    Professor Brian Kronvang

  61. Phosphorus Retention in Riparian Buffers: Review of Their Efficiency

    Article • Journal of Environmental Quality, January 2009, American Society of Agronomy

    Professor Brian Kronvang

  62. Climate Change Effects on Runoff, Catchment Phosphorus Loading and Lake Ecological State, and Potential Adaptations

    Article • Journal of Environmental Quality, January 2009, American Society of Agronomy

    Professor Brian Kronvang

  63. Can a priori defined reference criteria be used to select reference sites in Danish streams? Implications for implementing the Water Framework Directive

    Article • Journal of Environmental Monitoring, January 2009, Royal Society of Chemistry

    Professor Brian Kronvang, Dr Annette Baattrup-Pedersen

  64. Rivers of the Central European Highlands and Plains

    Article • January 2009, Elsevier

    Professor Brian Kronvang

  65. Towards European harmonised procedures for quantification of nutrient losses from diffuse sources—the EUROHARP project

    Article • Journal of Environmental Monitoring, January 2009, Royal Society of Chemistry

    Professor Brian Kronvang

  66. Description of nine nutrient loss models: capabilities and suitability based on their characteristics

    Article • Journal of Environmental Monitoring, January 2009, Royal Society of Chemistry

    Professor Brian Kronvang

  67. Ensemble modelling of nutrient loads and nutrient load partitioning in 17 European catchments

    Article • Journal of Environmental Monitoring, January 2009, Royal Society of Chemistry

    Professor Brian Kronvang

  68. Nitrogen and phosphorus retention in surface waters: an inter-comparison of predictions by catchment models of different complexity

    Article • Journal of Environmental Monitoring, January 2009, Royal Society of Chemistry

    Professor Brian Kronvang

  69. Effects of policy measures implemented in Denmark on nitrogen pollution of the aquatic environment

    Article • Environmental Science & Policy, April 2008, Elsevier

    Professor Brian Kronvang

  70. Nitrogen Transport and Fate in European Streams, Rivers, Lakes, and Wetlands

    Article • January 2008, Elsevier

    Professor Brian Kronvang

  71. Danish and other European experiences in managing shallow lakes

    Article • Lake and Reservoir Management, December 2007, Taylor & Francis

    Professor Brian Kronvang

  72. Modelling Phosphorus Retention in Lakes and Reservoirs

    Article • Water Air and Soil Pollution Focus, December 2006, Springer Science + Business Media

    Professor Brian Kronvang

  73. Water Exchange and Deposition of Sediment and Phosphorus during Inundation of Natural and Restored Lowland Floodplains

    Article • Water Air & Soil Pollution, November 2006, Springer Science + Business Media

    Professor Brian Kronvang

  74. Occurrence of Sediment-Bound Pyrethroids in Danish Streams and their Impact on Ecosystem Function

    Article • Water Air and Soil Pollution Focus, November 2006, Springer Science + Business Media

    Professor Brian Kronvang

  75. Interactions between Sediment and Water: Perspectives on the 10th International Association for Sediment Water Science Symposium

    Article • Water Air and Soil Pollution Focus, November 2006, Springer Science + Business Media

    Professor Brian Kronvang

  76. Modifying And Evaluating a P Index For Denmark

    Article • Water Air & Soil Pollution, July 2006, Springer Science + Business Media

    Professor Brian Kronvang

  77. Climate-change impacts on hydrology and nutrients in a Danish lowland river basin

    Article • The Science of The Total Environment, July 2006, Elsevier

    Professor Brian Kronvang

  78. Interactions Between Sediment and Water: Perspectives on the 10th International Association for Sediment Water Science Symposium

    Article • January 2006, Springer Science + Business Media

    Professor Brian Kronvang

  79. Occurrence of Sediment-Bound Pyrethroids in Danish Streams and Their Impact on Ecosystem Function

    Article • January 2006, Springer Science + Business Media

    Professor Brian Kronvang

  80. The Interactions Between Sediments and Water

    Article • January 2006, Springer Science + Business Media

    Professor Brian Kronvang

  81. Nutrient pressures and ecological responses to nutrient loading reductions in Danish streams, lakes and coastal waters

    Article • Journal of Hydrology, March 2005, Elsevier

    Professor Brian Kronvang

  82. Development, validation and application of Danish empirical phosphorus models

    Article • Journal of Hydrology, March 2005, Elsevier

    Professor Brian Kronvang

  83. Phosphorus Mobility in the Landscape

    Article • January 2005, American Society of Agronomy

    Professor Brian Kronvang

  84. Phosphorus Losses from Agricultural Areas in River Basins

    Article • Journal of Environmental Quality, January 2005, American Society of Agronomy

    Professor Brian Kronvang

  85. Hydromorphological and biological factors influencing sediment and phosphorus loss via bank erosion in small lowland rural streams in Denmark

    Article • Hydrological Processes, August 2003, Wiley

    Professor Brian Kronvang

  86. Phosphorus dynamics and export in streams draining micro‐catchments: Development of empirical models

    Article • Journal of Plant Nutrition and Soil Science, August 2003, Wiley

    Professor Brian Kronvang

  87. Estimating Annual River Discharge And Nitrogen Loadings To Danish Coastal Waters

    Article • International Journal of Environmental Studies, April 2003, Taylor & Francis

    Professor Brian Kronvang

  88. Interactions between sediments and water

    Article • Hydrobiologia, March 2003, Springer Science + Business Media

    Professor Brian Kronvang

  89. Macroinvertebrate/sediment relationships along a pesticide gradient in Danish streams

    Article • Hydrobiologia, March 2003, Springer Science + Business Media

    Professor Brian Kronvang

  90. Pesticides and heavy metals in Danish streambed sediment

    Article • Hydrobiologia, March 2003, Springer Science + Business Media

    Professor Brian Kronvang

  91. The Interactions between Sediments and Water

    Article • January 2003, Springer Science + Business Media

    Professor Brian Kronvang

  92. Macroinvertebrate/sediment relationships along a pesticide gradient in Danish streams

    Article • January 2003, Springer Science + Business Media

    Professor Brian Kronvang

  93. Interactions between sediments and water

    Article • January 2003, Springer Science + Business Media

    Professor Brian Kronvang

  94. Pesticides and heavy metals in Danish streambed sediment

    Article • January 2003, Springer Science + Business Media

    Professor Brian Kronvang

  95. Linked catchment and scenario analysis of nitrogen leaching and loading: a case-study from a Danish catchment-fjord system, Mariager Fjord

    Article • Physics and Chemistry of the Earth Parts A/B/C, January 2002, Elsevier

    Professor Brian Kronvang

  96. Nitrogen transport and fate in European streams, rivers, lakes and wetlands

    Article • January 2001, Elsevier

    Professor Brian Kronvang

  97. Establishment of a harmonized tool for calculating river discharge and nitrogen loads from unmonitored areas in Denmark

    Article • Physics and Chemistry of the Earth Part B Hydrology Oceans and Atmosphere, January 2001, Elsevier

    Professor Brian Kronvang

  98. Habitat surveys as a tool to assess the benefits of stream rehabilitation II: macroinvertebrate communities

    Article • SIL Proceedings 1922-2010, November 2000, Taylor & Francis

    Professor Brian Kronvang

  99. Lake and catchment management in Denmark

    Article • January 1999, Springer Science + Business Media

    Professor Brian Kronvang

  100. Subsurface Drainage Loss of Particles and Phosphorus from Field Plot Experiments and a Tile-Drained Catchment

    Article • Journal of Environmental Quality, January 1999, American Society of Agronomy

    Professor Brian Kronvang

  101. Scenario analysis of nutrient management at the river basin scale

    Article • January 1999, Springer Science + Business Media

    Professor Brian Kronvang

  102. Bank erosion in a Danish lowland stream system

    Article • January 1999, Springer Science + Business Media

    Professor Brian Kronvang

  103. Agricultural practices and diffuse nitrogen pollution in Denmark: Empirical leaching and catchment models

    Article • Water Science & Technology, January 1999, IWA Publishing

    Professor Brian Kronvang

  104. Trends in diffuse nutrient concentrations and loading in Denmark: Statistical trend analysis of stream monitoring data

    Article • Water Science & Technology, January 1999, IWA Publishing

    Professor Brian Kronvang

  105. Long-term, habitat-specific response of a macroinvertebrate community to river restoration

    Article • Aquatic Conservation Marine and Freshwater Ecosystems, January 1998, Wiley

    Professor Brian Kronvang

  106. Long‐term, habitat‐specific response of a macroinvertebrate community to river restoration

    Article • Aquatic Conservation Marine and Freshwater Ecosystems, January 1998, Wiley

    Professor Brian Kronvang

  107. Restoration of the Rivers Brede, Cole and Skerne: a joint Danish and British EU-LIFE demonstration project, IV—implications for nitrate and iron transformation

    Article • Aquatic Conservation Marine and Freshwater Ecosystems, January 1998, Wiley

    Professor Brian Kronvang

  108. Restoration of the Rivers Brede, Cole and Skerne: a joint Danish and British EU-LIFE demonstration project, IV—implications for nitrate and iron transformation

    Article • Aquatic Conservation Marine and Freshwater Ecosystems, January 1998, Wiley

    Professor Brian Kronvang

  109. Restoration of the rivers Brede, Cole and Skerne: a joint Danish and British EU-LIFE demonstration project, III—channel morphology, hydrodynamics and transport of sediment and nutrients

    Article • Aquatic Conservation Marine and Freshwater Ecosystems, January 1998, Wiley

    Professor Brian Kronvang

  110. Sediment and phosphorus export from a lowland catchment: Quantification of sources

    Article • Water Air & Soil Pollution, October 1997, Springer Science + Business Media

    Professor Brian Kronvang

  111. SUSPENDED SEDIMENT AND PARTICULATE PHOSPHORUS TRANSPORT AND DELIVERY PATHWAYS IN AN ARABLE CATCHMENT, GELBÆK STREAM, DENMARK

    Article • Hydrological Processes, May 1997, Wiley

    Professor Brian Kronvang

  112. Sediment and Phosphorus Export from a Lowland Catchment: Quantification of Sources

    Article • January 1997, Springer Science + Business Media

    Professor Brian Kronvang

  113. CHOICE OF SAMPLING STRATEGY AND ESTIMATION METHOD FOR CALCULATING NITROGEN AND PHOSPHORUS TRANSPORT IN SMALL LOWLAND STREAMS

    Article • Hydrological Processes, November 1996, Wiley

    Professor Brian Kronvang

  114. Loss of dissolved and particulate phosphorus from arable catchments by subsurface drainage

    Article • Water Research, November 1996, Elsevier

    Professor Brian Kronvang

  115. Diffuse nutrient losses in denmark

    Article • Water Science & Technology, January 1996, IWA Publishing

    Professor Brian Kronvang

  116. Dynamics of phosphorus compounds in a lowland river system: Importance of retention and non‐point sources

    Article • Hydrological Processes, February 1995, Wiley

    Professor Brian Kronvang

  117. Restoration of a channelized reach of the River Gelså, Denmark: Effects on the macroinvertebrate community

    Article • Aquatic Conservation Marine and Freshwater Ecosystems, December 1994, Wiley

    Professor Brian Kronvang

  118. Re‐establishment of Danish streams: Restoration and maintenance measures

    Article • Aquatic Conservation Marine and Freshwater Ecosystems, June 1993, Wiley

    Professor Brian Kronvang

  119. Retention of nitrogen and phosphorus in a Danish lowland river system: implications for the export from the watershed

    Article • Hydrobiologia, February 1993, Springer Science + Business Media

    Professor Brian Kronvang

  120. Retention of nitrogen and phosphorus in a Danish lowland river system: implications for the export from the watershed

    Article • January 1993, Springer Science + Business Media

    Professor Brian Kronvang

  121. The export of particulate matter, particulate phosphorus and dissolved phosphorus from two agricultural river basins: Implications on estimating the non-point phosphorus load

    Article • Water Research, October 1992, Elsevier

    Professor Brian Kronvang

  122. Modelling Phosphorus Retention in Lakes and Reservoirs

    Article • Springer Science + Business Media

    Professor Brian Kronvang

  123. Quantifying sediment and nutrient pathways within Danish agricultural catchments.

    Article • CABI Publishing

    Professor Brian Kronvang