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Linking habitat suitability and seed dispersal models in order to analyse the effectiveness of hydrological fen restoration strategies 总被引：1，自引：0，他引：1
A.H. van Loon H. Soomers P.P. Schot M.F.P. Bierkens J. Griffioen M.J. Wassen 《Biological conservation》2011,(3):1025-1035
The effectiveness of measures targeted at the restoration of populations of endangered species in anthropogenically dominated regions is often limited by a combination of insufficient restoration of habitat quality and dispersal failure. Therefore, the joint prediction of suitable habitat and seed dispersal in dependency of management actions is required for effective nature management. Here we demonstrate an approach, which links a habitat suitability and a seed dispersal model. The linked model describes potential species distribution as a function of current species distribution, species-specific dispersal traits, the number of successful dispersal events, dispersal infrastructure and habitat configuration. The last two variables were related to water management actions. We demonstrate the applicability of the model in a strategy analysis of hydrological restoration measures for a large fen area in which still numerous endangered plant species grow.With the aid of the linked model, we were able to optimise the spatial planning of restoration measures, taking into account both the constraints of water management practices on abiotic restoration and the effects of habitat fragmentation on dispersal. Moreover, we could demonstrate that stand-alone habitat suitability models, which assume unlimited dispersal, may considerably overestimate restoration prospects. For these reasons, we conclude that linked habitat suitability and dispersal models can provide useful insights into spatially differentiated potentials and constraints of nature restoration measures targeted at the sustainable conservation of endangered plant populations whose habitats have been deteriorated due to undesirable effects of land and water management on abiotic conditions. These insights may contribute to the design of cost-effective nature restoration and conservation measures. 相似文献
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René R. Wijngaard Marcel van der Perk Bas van der Grift Ton C. M. de Nijs Marc F. P. Bierkens 《Water, air, and soil pollution》2017,228(3):107
This study investigates the impact of future climate change on heavy metal (i.e., Cd and Zn) transport from soils to surface waters in a contaminated lowland catchment. The WALRUS hydrological model is employed in a semi-distributed manner to simulate current and future hydrological fluxes in the Dommel catchment in the Netherlands. The model is forced with climate change projections and the simulated fluxes are used as input to a metal transport model that simulates heavy metal concentrations and loads in quickflow and baseflow pathways. Metal transport is simulated under baseline climate (“2000–2010”) and future climate (“2090–2099”) conditions including scenarios for no climate change and climate change. The outcomes show an increase in Cd and Zn loads and the mean flux-weighted Cd and Zn concentrations in the discharged runoff, which is attributed to breakthrough of heavy metals from the soil system. Due to climate change, runoff enhances and leaching is accelerated, resulting in enhanced Cd and Zn loads. Mean flux-weighted concentrations in the discharged runoff increase during early summer and decrease during late summer and early autumn under the most extreme scenario of climate change. The results of this study provide improved understanding on the processes responsible for future changes in heavy metal contamination in lowland catchments. 相似文献
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Christa Cornelis Johan Bierkens Ingeborg Joris Peter Nielsen Stany Pensaert 《Journal of Soils and Sediments》2006,6(3):156-162
Background, Aim and Scope
The use of organotin compounds as antifouling agents on ships is prohibited at EU level since 1 July 2003. Because of its
persistence, the presence of organotin compounds in harbour sediment will however remain a problem for years. Dumping of dredged
sediment in sea is subject to very strict quality criteria, stimulating the exploration of re-use alternatives, such as re-use
on land.
Within the TBT Clean project (EU LIFE Project 02/ENV/B/341) an assessment framework for re-use of organotin containing treated
sediment on land as secondary granular building material was developed. Three scenarios were considered: free re-use on land,
re-use above groundwater level with cover layer, and re-use under groundwater level (the latter two scenarios are referred
to as restricted re-use). Receptors considered were humans, ecosystem and groundwater. Generic upper concentration limits
and sediment leaching limits were calculated.
Materials and Methods:
Upper concentration limits were calculated with the Vlier-Humaan model. This model allows to calculate soil remediation values
according to the Flemish legal framework. The focus of the methodology is the protection of human health, although a check
for ecotoxicity was included in the project. The soil remediation value for residential land-use was selected within the scenario
for free re-use; for restricted re-use (no direct contact possible), the soil remediation value for industrial land-use was
selected. Leaching values were calculated with an analytical soil and groundwater transport model. The reference scenario
behind the leaching criteria of the European Landfill Directive was modified to fit the project objectives. Default values
for application height and length were used. The point-of-compliance was situated at 20 m distance in the groundwater. Physicochemical
properties were taken from literature; sorption characteristics were taken from literature and were measured on 6 treated
sediment samples during the project. Plant-uptake values were taken from the literature. Toxicological criteria were taken
from EFSA.
Results:
The assessment framework provided an upper limit (SedUL) and an leaching value (SedLV) for each scenario, expressed as mg/kg
dm in the sediment. Criteria were calculated for tributyltin (TBT) and dibutyltin (DBT); too few data were available for monobutyltin
(MBT). The SedUL equalled 0.51 mg TBT/kg dm and 0.07 mg DBT/kg dm for free re-use and 195 mg TBT/kg dm and 205 mg DBT/kg dm
for restricted re-use (two scenarios). For free re-use the SedLV was only limiting for TBT at Kd of < 2000 l/kg in the sediment.
Under re-use above groundwater level with coverage SedLV values ranged from 6.9 – 29 mg TBT/kg dm and from 12 – 33.3 mg DBT/kg
dm (Kd ranging from 100 – 10000 l/kg); under re-use below groundwater level SedLV values ranged from 0.007 – 0.77 mg TBT or
DBT/kg dm (Kd ranging from 100 – 10000 l/kg).
Discussion:
Results are subject to large uncertainties because of variation in input data; the model output is sensitive to variation
in plant uptake (SedUL for free re-use), Koc or Kd (SedUL for restricted re-use, SedLV for re-use with coverage), Henry's
law coefficient (SedUL for restricted re-use); all these parameters show orders of magnitude variation.
Conclusions:
A feasible and consistent framework for evaluation of the re-use of treated organotin containing sediment was developed. However,
the resulting quality criteria are still subject to large uncertainties, due to uncertainties in input data.
Recommendations and Perspectives:
High-quality data on plant uptake and soil sorption of organotin compounds, the influence of soil properties on these processes,
and long-term terrestrial toxicity data are needed to refine the calculations. The quality criteria should be reviewed when
these data become available. 相似文献
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