Nuttige idioten: het (on)bedoeld maatschappelijk verval door sociaal activisme

Hoe kan men een staat intern ten val brengen? Dit was één van de taken waar de KGB, de belangrijkste geheime dienst van de Sovjet-Unie, zich mee bezighield. Bij de rol van de KGB in de tijd van de Koude Oorlog doet men al snel denken aan spionage. Hoewel er aan spionage werd gedaan, lag het zwaartepunt van de KGB hier niet. Geschat wordt dat slechts 15% van de KGB haar tijd, geld en mankracht besteedde aan spionage. De overige 85% werd besteed aan een langzaam proces dat ideologische ondermijning wordt genoemd.

Innovatie een optie?: de psychologie van bestuurskundigen die de gemakkelijke weg kiezen

Een van de grootste clichés in het openbaar bestuur is dat men voor daadkrachtig en innovatief beleid het beste kan zoeken in de private sector. Uit de bestuurskundige wetenschap blijkt dan ook dat innovatie in de publieke sector minder vaak voorkomt en grotere barrières ondervindt. Zo bestaan er bepaalde factoren die ervoor zorgen dat organisaties in de publieke sector vaak inderdaad blijven hangen in oude gewoonten. De stand van zaken wordt dus vaak gehandhaafd in overheidsorganisaties. Maar hoe gebeurt dit nou precies, en wat zijn deze hinderende factoren? Dit wordt beschouwd in het eerste deel van het artikel. Zijn er wellicht ook blinde vlekken? En hoe kan de bestuurskunde als wetenschap hiermee vooruit? Hier zal het tweede deel van het artikel op ingaan

Regional scale evaluation of nitrate fluctuations in groundwater using cluster analysis and standardised hydrometeorological indices

Temporal fluctuations in nitrate in groundwater can result in concentrations temporarily exceeding drinking water standards, resulting in costly water treatment or blending. The extent and potential controls on these fluctuations are poorly understood, particularly at regional to national scales. Applied to southeast England (UK), we develop the first application of cluster analysis and standardised hydrometeorological indices to evaluate nitrate fluctuations in groundwater. Cluster analysis of 96 groundwater nitrate time series showed that nitrate time series can be divided into 4 clusters: (1) long term increasing trends (n = 23, mean trend = 0.26 mg NO3/l/a), (2) long term decreasing trends (n = 19, mean trend = - 0.65 mg NO3/l/a), (3) long term increasing trends with seasonal fluctuations (n = 24, mean trend = 0.29 mg NO3/l/a) and (4) long term increasing trends superimposed on near-decadal scale fluctuations (n = 30, mean trend = 0.22 mg NO3/l/a). There is weak spatial coherence in the clustering, with clusters 3 and 4 present in the South and North Downs respectively. Cross-correlation analysis between groundwater nitrate time series with precipitation and groundwater level indices showed that rapid seasonal fluctuations in nitrate concentrations in cluster 3 in the South Downs are associated with rapidly responding groundwater level fluctuation. This is likely due to the highly fractured and faulted nature of the Chalk aquifer in this area. The strongest correlations between groundwater levels and nitrate concentrations in cluster 3 occurred when cross-correlating at a lag of zero months, which suggests that matrix diffusion is unlikely to be a significant control on seasonality. Seasonal fluctuations in nitrate concentrations are likely to be associated with piston displacement and changing groundwater flow paths. The methodology developed here is generic and can be applied wherever there is a large body of groundwater nitrate time series data

Regional scale evaluation of nitrate fluctuations in groundwater using cluster analysis and standardised hydrometeorological indices

Temporal fluctuations in nitrate in groundwater can result in concentrations temporarily exceeding drinking water standards. This can bring about the need for costly water treatment or blending. Despite this, the extent and potential controls on these fluctuations are poorly understood, particularly at regional to national scales. Applied to Southeast England (UK), here we develop the first application of cluster analysis and standardised hydrometeorological indices to evaluate nitrate fluctuations in groundwater at the regional scale. Hierarchical and K-means cluster analysis of 96 groundwater nitrate time series for the period 1995–2022 showed that nitrate time series can be divided into 4 clusters: (1) long term increasing trends (n = 23, mean trend = 0.26 mg NO3/l/a), (2) long term decreasing trends (n = 19, mean trend = − 0.65 mg NO3/l/a), (3) long term increasing trends with seasonal fluctuations (n = 24, mean trend = 0.29 mg NO3/l/a) and (4) long term increasing trends superimposed on near-decadal scale fluctuations (n = 30, mean trend = 0.22 mg NO3/l/a). Boreholes in cluster 1 appear to be deeper than boreholes in cluster 2. In comparison to shallower boreholes, deeper boreholes are likely to be intersecting longer groundwater flow systems where nitrate concentrations are affected by historic “legacy nitrate” leaching. There is weak spatial coherence in the clustering, with clusters 3 and 4 present in the South and North Downs respectively. Cross-correlation analysis between groundwater nitrate time series with precipitation and groundwater level indices showed that rapid seasonal fluctuations in nitrate concentrations in cluster 3 in the South Downs are associated with rapidly responding groundwater level fluctuation. This is likely due to the highly fractured and faulted nature of the Chalk aquifer in this area. This is in contrast with the slower near-decadal fluctuations in cluster 4 in the North Downs. The strongest correlations between groundwater levels and nitrate concentrations in cluster 3 occurred when cross-correlating at a lag of zero months, which would suggest that matrix diffusion is unlikely to be a significant control on nitrate seasonality. Seasonal fluctuations in nitrate concentrations are likely to be associated with a combination of piston displacement at the water table and changing groundwater flow paths to the borehole. Future climate change may change the magnitude and timing of seasonal fluctuations caused by these processes. The methodology developed here is generic and can be applied wherever there is a large body of groundwater nitrate time series data

The impact of climate change on groundwater recharge: National-scale assessment for the British mainland

Groundwater systems provide an important source of water supply as well as contributing baseflow to rivers, lakes and dependent ecosystems and so the impact of climate change on these systems needs to be understood. Calculating recharge to groundwater systems is, therefore, necessary to quantify what is typically one of the largest components of the groundwater balance. This study uses the national-scale recharge model developed for the British mainland and the 11 ensemble members from the Hadley Centre for rainfall and potential evaporation created by the Future Flows and Groundwater Levels (FFGWL) project to investigate the impact of future climate on groundwater resources. Changes to seasonal and monthly recharge for the 2050s and 2080s time slices have been produced for the whole modelled area and for river basin districts for England and Wales. Areal summaries and monthly time series of recharge values show a generally consistent trend of increased recharge in winter, decreased recharge in summer, and mixed pattern in autumn and spring. The work shows that increased winter rainfall is the main factor in increasing recharge. Water balance calculations reveal that over the 2050s and 2080s, the climate change “signal” predominates over the annual variability, which results in a clearer pattern of more recharge being concentrated in fewer months. This finding should prove useful for water resources planners to assess the resilience of groundwater resources to climate change. Further work is recommended to understand the sequencing of flooding and drought events and to the effects of soil health and land cover changes in the future analysis