Review of the effects of non-point nutrient loading on coastal ecosystems

1993 ◽  
Vol 44 (2) ◽  
pp. 261 ◽  
Author(s):  
AJ Gabric ◽  
PRF Bell
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Coastal Zone ◽  
Land Use Planning ◽  
Large Scale ◽  
Nutrient Loading ◽  
Algal Growth ◽  
Effective Control ◽  
Nutrient Load ◽  
Northern Adriatic

In many coastal regions (e.g. parts of the North Sea, northern Adriatic Sea, Baltic Sea, Great Barrier Reef lagoon, wider Caribbean, coastal areas of the USA) there is large-scale, and in some cases chronic, eutrophication. In some regions, the link between eutrophication and the destruction of an ecosystem is obvious, with excessive algal growth and water-column anoxia. In other cases, particularly in more fragile ecosystems such as coral-reef and seagrass areas, the links are not so obvious, yet the impacts of eutrophication in such regions can be devastating. Eutrophication can have more insidious effects such as contributing directly to the mortality of fish, marine mammals and sea birds and indirectly to disease or death in humans owing to the accumulation of biotoxins in seafoods. Increased development and changes in land-use patterns in the coastal zone have increased the loading of diffuse or non-point nutrients. In areas subject to runoff and soil erosion, most of the nutrient load is transported in particulate form. In such cases, the loads of nutrients discharged from cropping lands are typically an order of magnitude greater than those discharged from pristine forested areas. Nutrient export from pasture lands, whether these are fertilized or not, is also significantly greater than that from pristine areas, and in many cases the total loads from such areas are far higher than those from intensively farmed areas. A reduction in nutrient discharges to coastal waters will require careful land-use planning. The importance of the particulate fraction in the nutrient load necessitates effective control of soil erosion. The hydrological and nutrient linkage between terrestrial and marine ecosystems must be emphasized. Collective management of hinterland and coastal-zone resources could initiate remediation of a serious and growing problem.

scholarly journals Effects of Vegetation Restoration on Soil Erosion on the Loess Plateau: A Case Study in the Ansai Watershed

2021 ◽  
Vol 18 (12) ◽  
pp. 6266
Author(s):  
Hui Wei ◽  
Wenwu Zhao ◽  
Han Wang
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Loess Plateau ◽  
Water Conservation ◽  
Large Scale ◽  
Land Use Changes ◽  
Vegetation Restoration ◽  
The Loess Plateau ◽  
Local Soil ◽  
Erosion Environment

Large-scale vegetation restoration greatly changed the soil erosion environment in the Loess Plateau since the implementation of the “Grain for Green Project” (GGP) in 1999. Evaluating the effects of vegetation restoration on soil erosion is significant to local soil and water conservation and vegetation construction. Taking the Ansai Watershed as the case area, this study calculated the soil erosion modulus from 2000 to 2015 under the initial and current scenarios of vegetation restoration, using the Chinese Soil Loess Equation (CSLE), based on rainfall and soil data, remote sensing images and socio-economic data. The effect of vegetation restoration on soil erosion was evaluated by comparing the average annual soil erosion modulus under two scenarios among 16 years. The results showed: (1) vegetation restoration significantly changed the local land use, characterized by the conversion of farmland to grassland, arboreal land, and shrub land. From 2000 to 2015, the area of arboreal land, shrub land, and grassland increased from 19.46 km2, 19.43 km2, and 719.49 km2 to 99.26 km2, 75.97 km2, and 1084.24 km2; while the farmland area decreased from 547.90 km2 to 34.35 km2; (2) the average annual soil erosion modulus from 2000 to 2015 under the initial and current scenarios of vegetation restoration was 114.44 t/(hm²·a) and 78.42 t/(hm²·a), respectively, with an average annual reduction of 4.81 × 106 t of soil erosion amount thanks to the vegetation restoration; (3) the dominant soil erosion intensity changed from “severe and light erosion” to “moderate and light erosion”, vegetation restoration greatly improved the soil erosion environment in the study area; (4) areas with increased erosion and decreased erosion were alternately distributed, accounting for 48% and 52% of the total land area, and mainly distributed in the northwest and southeast of the watershed, respectively. Irrational land use changes in local areas (such as the conversion of farmland and grassland into construction land, etc.) and the ineffective implementation of vegetation restoration are the main reasons leading to the existence of areas with increased erosion.

scholarly journals Assessment of the risk of soil erosion using RUSLE method and SWAT model at the M’dez Watershed, Middle Atlas, Morocco

2020 ◽  
Vol 150 ◽  
pp. 03014 ◽  
Author(s):  
M’hamed Boufala ◽  
Abdellah El Hmaidf ◽  
Khalid Chadli ◽  
Ali Essahlaoui ◽  
Abdelhadi El Ouali ◽  
...  
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Land Use Planning ◽  
Swat Model ◽  
Sustainable Land Use ◽  
Rusle Model ◽  
Mediterranean Countries ◽  
Dam Reservoirs ◽  
Middle Atlas ◽  
Soil Losses

The preservation of soil resources is a primary global concern and a permanent challenge for all Mediterranean countries. In Morocco, the capacity of dam reservoirs continues to decline from one year to the next due to the rate of siltation, mainly due to the phenomenon of water erosion. Indeed, the origins of this erosion are generally related to land use planning, deforestation, agricultural practices and low vegetation cover. However, it is imperative to quantify soil erosion and its spatial distribution to achieve sustainable land use and governance of this resource. The SWAT hydro-agricultural model and the integrated RUSLE model were used to assess soil losses and characterize the degraded areas of the M’dez watershed, located in the upper Sebou, north of the Middle Atlas, and extend on an area of 3350 km2. The results obtained during this work show that the average soil losses estimated by the two models are consistent. For the SWAT model, the specific degradation of the watershed is estimated at 3.95 t/ha/year, whereas for the RUSLE model, the average loss of the basin is estimated at 2.94 t/ha/year). However, the use of these two models (SWAT and RUSLE), for the assessment and characterization of degraded areas at the level of Moroccan watersheds, has become a much sought-after approach for good soil conservation management.

Nutrient load simulations at Lake Puruvesi, Finland: extreme case event in 2012

2020 ◽  
Author(s):  
Natalia Korhonen ◽  
Sirkka Tattari ◽  
Antti Leinonen ◽  
Markus Huttunen ◽  
Leena Finér ◽  
...  
Keyword(s):  
Land Use ◽  
Nutrient Loading ◽  
Snow Water Equivalent ◽  
Urban Land Use ◽  
Nutrient Load ◽  
Total Precipitation ◽  
Snow Melt ◽  
Weather Station ◽  
Model Simulations ◽  
Snow Water

<p>In the Open-Air Laboratory (OAL)-Finland, Lake Puruvesi, the main land-use is forested areas, with minor areas in agriculture, and urban land-use. Activities related to these land-uses together with infrequently occurring high runoff peaks due to heavy rain events or rapid snowmelt cause nutrient (phosphorus, nitrogen) and sediment load risks and thus threaten recreation, fishing (professional and recreational) and biodiversity of the area. Various Nature- Based Solutions (NBS) are planned to reduce nutrient loading for the Puruvesi area. Modelling will be used to estimate the impact of NBSs on nutrient loading. It is important to increase understanding of the impacts of the extreme weather events on the amount of nutrient concentration in the water.</p><p>According to model simulations the nutrient load increases during the years with high precipitation. However, the total annual precipitation alone explain only partly the variations in the nutrient loads. The nutrient load depends also on the timing of the precipitation and the moisture condition and nutrient content of soil before the precipitation or snow melting event. Typically in Finland, the high nutrient load peaks take place during spring snow melt or after the autumn precipitation. Heavy precipitation during summer may as well induce a peak in nutrient concentrations.</p><p>Here we focus on the impacts of an extreme spring snow melt event in year 2012. In the Puruvesi region the winter 2012 was wetter than average with snow depths reaching more than 50 cm in March and lasting until mid-April. During the permanent snow cover period (31.12.2011-23.4.2012) the total precipitation was 150 mm at the weather station in the Lake Puruvesi catchment area. The snow water equivalent, i.e., the amount of water contained within the snow, is not measured in Lake Puruvesi. However, the Finnish Environment Institute produces estimates of snow water equivalents over Finland with the Watershed simulation and forecasting system (VEMALA). According to modelling the snow water equivalent was about 120 mm in mid-April in Savonlinna located about 10 km west from the Punkaharju weather station. The whole snow pack melted during 13 days (11.4.2012-23.4.2012) from 50 cm to 0 cm as the daily mean temperatures rose permanently above 0 °C. During the snow melt period the total precipitation was about 30 mm. The VEMALA model simulations show a peak of 90 µg/l in phosphorus concentrations during the snow melt in the end of April 2012. As a comparison, the drier than average year, 1993, with less snow (max depth 30 cm and slower melting) lead to a lower phosphorus concentration peak of 60 µg/l. Furthermore, the total phosphorus load in 2012 was 2.5 times higher than the load in 1993. This review demonstrates that, in extreme years, the number or effectiveness of NBS measures must be significantly increased to achieve the required reduction in nutrient leaching compared to normal or drier years.</p><p>The work is carried out as co-operation between OPERANDUM EU and Freshabit Life IP -projects.</p>

scholarly journals Modeling long-term, large-scale sediment storage using a simple sediment budget approach

2016 ◽  
Vol 4 (2) ◽  
pp. 407-423 ◽  
Author(s):  
Victoria Naipal ◽  
Christian Reick ◽  
Kristof Van Oost ◽  
Thomas Hoffmann ◽  
Julia Pongratz
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Land Use Change ◽  
Large Scale ◽  
Last Millennium ◽  
Earth System ◽  
Sediment Storage ◽  
Global Soil ◽  
Rhine Catchment

Abstract. Currently, the anthropogenic perturbation of the biogeochemical cycles remains unquantified due to the poor representation of lateral fluxes of carbon and nutrients in Earth system models (ESMs). This lateral transport of carbon and nutrients between terrestrial ecosystems is strongly affected by accelerated soil erosion rates. However, the quantification of global soil erosion by rainfall and runoff, and the resulting redistribution is missing. This study aims at developing new tools and methods to estimate global soil erosion and redistribution by presenting and evaluating a new large-scale coarse-resolution sediment budget model that is compatible with ESMs. This model can simulate spatial patterns and long-term trends of soil redistribution in floodplains and on hillslopes, resulting from external forces such as climate and land use change. We applied the model to the Rhine catchment using climate and land cover data from the Max Planck Institute Earth System Model (MPI-ESM) for the last millennium (here AD 850–2005). Validation is done using observed Holocene sediment storage data and observed scaling between sediment storage and catchment area. We find that the model reproduces the spatial distribution of floodplain sediment storage and the scaling behavior for floodplains and hillslopes as found in observations. After analyzing the dependence of the scaling behavior on the main parameters of the model, we argue that the scaling is an emergent feature of the model and mainly dependent on the underlying topography. Furthermore, we find that land use change is the main contributor to the change in sediment storage in the Rhine catchment during the last millennium. Land use change also explains most of the temporal variability in sediment storage in floodplains and on hillslopes.

scholarly journals Data integration and participatory process in developing integrated coastal zone management (ICZM) in the northern Baltic Sea

2021 ◽  
Vol 25 (5) ◽  
Author(s):  
Reija Hietala ◽  
Asko Ijäs ◽  
Tarmo Pikner ◽  
Anne Kull ◽  
Anu Printsmann ◽  
...  
Keyword(s):  
Land Use ◽  
Coastal Zone ◽  
Land Use Planning ◽  
Spatial Data ◽  
Coastal Zone Management ◽  
Assessment Tools ◽  
Integrated Coastal Zone Management ◽  
The European Union ◽  
Participatory Gis ◽  
Zone Management

AbstractThe Maritime Spatial Planning (MSP) Directive was ratified (2014/89/EU) along the Strategy of the European Union (EU) on the Blue Economy to contribute to the effective management of maritime activities and resources and incorporate the principal elements of Integrated Coastal Zone Management (ICZM) (2002/413/EC) into planning at the land-sea interface. There is a need to develop the ICZM approach throughout Europe to realise the potential for both socio-economic and environmental targets set by the EU and national legislations. In this study, we co-developed different approaches for land-sea interactions in four case areas in Estonia and Finland based on the defined characteristics and key interests derived from local or regional challenges by integrating spatial data on human activities and ecology. Furthermore, four ICZM drafts were co-evaluated by stakeholders and the public using online map-based assessment tools (public participatory GIS). The ICZM approaches of the Estonian cases ranged from the diversification of land use to the enhancement of community-based entrepreneurship. The Finnish cases aimed to define the trends for sustainable marine and coastal tourism and introduce the ecosystem service concept in land use planning. During the project activities, we found that increased communication and exchange of local and regional views and values on the prevailing land-sea interactions were important for the entire process. Thereafter, the ICZM plans were applied to the MSP processes nationally, and they support the sustainable development of coastal areas in Estonia and Finland.

scholarly journals IDENTIFICATION AND MAPPING OF HOT SPOT AREAS SUSCEPTIBLE TO SOIL EROSION IN ERAK AL KARAK AREA USING GEOINFORMATICS

2018 ◽  
Vol 6 (6) ◽  
pp. 246-259
Author(s):  
Safa Mazahreh ◽  
Mohammad Alkharabsheh ◽  
Majed Bsoul ◽  
Doaa Abu Hammor ◽  
Lubna Al Mahasneh
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Land Degradation ◽  
Land Use Planning ◽  
Soil Loss ◽  
Hot Spot ◽  
Gis Tools ◽  
Areas Of Interest ◽  
Agricultural Areas ◽  
The Impact

Jordan is a country dominated by arid climate and fragile ecological system, where 91% is classified as arid land with annual average rainfall rarely exceeds 200 mm/y. Therefore, land degradation, soil erosion and desertification are important areas of interest, where soil erosion is considered one of the major causes for land degradation in Jordan. The main objective of this study is to create an erosion hazard map and identify the areas susceptible to soil erosion in Erak Al karak watershed in southern part of Jordan. Soil erosion model RUSLE with the integration of GIS tools has been developed to estimate the annual soil loss. The estimated mean annual soil loss is (38.7 ton/ ha/year). The erosion map produced highlighted the hot spot areas susceptible to soil erosion. A relationship was obvious between terraces land use and soil loss, where 22% of the soil loss was reduced by applying soil conservation technique (terraces). According to this model, most of the hot spot areas are located in the rangeland 63% while the agricultural areas are responsible for 14% of the hot spot areas. The results emphasis the importance of urgent land use planning and conservation practices to reduce the impact of soil erosion.

Sign in / Sign up

Export Citation Format

Share Document