Saline Agriculture as a Solution Lessons from the socio-agricultural system of Goeree-Overflakkee

Saline Agriculture as a Solution

Lessons from the socio-agricultural

system of Goeree-Overflakkee

Lieke Moonen 10449264

Lien Moonen 10459111

Noah Pierau 10349804

Expert: dr. K.F. (Kenneth) Rijsdijk

Tutor: dr. M.F. (Maartje) Hamers

Word count: 8871

The expected increase of primary salinisation might threaten agricultural production if not acted upon, causing social disturbances. This report investigates saline agriculture as a possible solution to make

socio-agricultural systems more resilient to the effects of primary salinisation. Insights from the disciplines of Earth Science, Anthropology and Political Science are integrated to address the interdisciplinary research question and the sub-objectives. First of all, the effects of salinisation have been explicated. By means of a literature study and empirical research in the chosen case-study of Goeree-Overflakkee, the feasibility and implementation have been researched. Saline agriculture has proven to be feasible in the case-study area under certain conditions. Implementation was found to be successful if a stage-targeted and participatory approach is employed. Institutions can facilitate the transition to saline agriculture by applying strategic niche management. Based on these results, it can be concluded that saline agriculture may indeed be a possible and needed solution to make socio-agricultural systems in the Netherlands resilient to the effects of primary salinisation.

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ONTENT

The effects of primary soil salinisation... 10

Introduction... 10

Methodology... 10

Salinisation... 10

Sub-conclusions... 13

The case-study area... 14

Introduction... 14

Methodology... 14

Sub-conclusion... 18

The Feasibility of Saline Agriculture... 19

Introduction... 19

Methodology... 19

What about the Farm?... 20

What about the Farmers?... 25

Sub-conclusion... 28

The Implementation of Saline Agriculture...29

Introduction... 29

Methodology... 29

Five stages of implementation... 29

Non Stage Specific Results... 31

Sub-conclusion... 32

Conclusion... 33

Discussion... 34

References... 35

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NTRODUCTION

The forecasted sea level rise due to climate change (Solomon et al., 2007) of the coming decades will cause an alteration of the hydrology of many countries such as an increasing number of flooding events (Nicholls et al., 1999). In addition, it will lead to an alteration of the soils of the affected countries (Day & Templet, 1989). Salt water will infiltrate the soils both by flooding and by seepage in non-flooding areas. This so called ‘primary salinisation’ has severe effects on agriculture, for regular crops do not ideally grow on saline soils.

Primary salinisation increasingly receives attention in the Netherlands, especially because of potential consequences for agriculture (De Boer & Radersma, 2011). Agriculture stands at the base of human food supply, which causes it to be indispensable and of great societal relevance. Recent solutions have mainly focussed on preventing salinisation, in the Netherlands primarily by flushing the soil with fresh water retained from the surroundings (Rijksoverheid, 2014). However, since future fresh water shortages are expected, these solutions are not sustainable. It is therefore essential to make the agricultural sector Netherlands resilient to salinisation.

‘Saline agriculture’ (SA) might prove as a solution (Breckle, 2009). Here, saline agriculture will be defined as a cultivation method which cultivates salt tolerant (halophytic) crops on saline soils, using saline irrigation water. Recent research has addressed saline agriculture from an Earth and Soil Sciences point of view. However, other disciplines add important insights. Anthropological research is needed to gain insight in the willingness of farmers in (future) saline areas to change their professional methods. Furthermore, Political Science is needed in order to investigate how the implementation process can be facilitated. The concept ‘socio-agricultural system’ (SAS) will be introduced to combine the insights of Earth and Soil Science, Anthropology and Political Science.

Arising from this, the main research question of this report can be formulated as: How can the implementation of saline agriculture make socio-agricultural systems in the Netherlands resilient to the effects of primary salinisation?

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Following from the above mentioned, this report requires an interdisciplinary approach because it complies with Repko’s four criteria: 1) The problem or question is complex. 2) Different disciplines offer important insights into the problem. 3) The question or problem has not been addressed extensively by more than one discipline. 4) The problem is of societal relevance (Repko, 2012, p.84)

The research question is complex because answering the multiple sub-objectives requires the knowledge of different disciplines. SA might prove to be technically possible in theory. Yet, it can only serve as a solution if farmers accept it as a solution. This might be facilitated by institutions. Therefore, SA needs to be researched from different perspectives. Finally SA can play an important role in maintaining the important ecosystem service of agriculture on saline-prone areas, and is therefore relevant for society.

Figure 1 visualises the main research structure. Firstly, the effects of salinisation in the Netherlands will be analysed in a literature study. Secondly, a case-study area will be selected as the fundament for the sequel of the research. Then, we will zoom in on the feasibility of SA, which will be investigated by performing empirical and literature research. Thirdly, the implementation the (possibly feasible) SA will be studied. Finally, we will zoom out again in order to draw conclusions and extrapolate the results from the case study area to gain more general knowledge on saline agriculture in the Netherlands.

Each of the sections described in figure 1 will define its own methodology, since different techniques will be employed for different objectives. In order to adequately address the main research question, the main concepts will be defined in the theoretical framework..

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The common theme running throughout this research, is Resilience Thinking - a concept introduced by Holling in 1973 within the ecological discipline. Resilience describes the ability of an ecosystem to cope with external disturbances. For this research, the fundamentals of the theory have been used and extended (Repko, 2012, p. 340) to an interdisciplinary theory, creating common ground between the different disciplines of earth sciences, political sciences and anthropology.

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Figure 2 visualises how SA could act as a solution to the negative effects of salinisation on agriculture. The entire slide represents the landscape where processes occur. The ball represents the current state of the system. This current state may shift to another state by external disturbances (the dotted line), in this case salinisation. If salinisation is pressuring the current state severely, it can cross the systems tipping point and shift to the second state.

For the purpose of describing the two different systems (the two valleys), we created the concept Socio-Agricultural System (SAS; figure 3). This refers to the entire system surrounding agricultural food production and is composed of three elements. Firstly, the Farm and its biochemical properties, mainly soil and crop properties (Earth Sciences). Secondly, the Farmer -the main actor, which represents the human side of agricultural production (Anthropology). And thirdly, the Institutions - the major players that determine the social and political conditions around agriculture (Political Sciences). Evidently, these elements are dynamically interrelated

for their conditions depend on each other's conditions. The entire system has an ecosystem service: agricultural food production.

Reverting to the Resilience Thinking, in figure 4 the current state is situated in a ‘healthy’ SAS. This entails that the systems ecosystem service of agricultural food production can be performed. However, salinisation might push the current state into the second state, a ‘collapsed’ SAS, in which agriculture is not possible anymore.

The vision of this research is that the system’s tipping point should be elevated in order to increase the resilience of the system’s SAS. Saline agriculture can use the changing saline conditions ,instead of combating them. In this way, the current state could stay within a healthy SAS, and agricultural production would be safeguarded.

In order to research if SA could actually induce this effect, all three elements of the SAS should be studied.

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The Farm is not an actor in the SAS, but is being influenced by the Farmer and the Institutions. Changes from salinisation as well as from SA become visible on here. The Farm sets the conditions that determine whether these changes are both possible and needed.

In this research, the soils are approached according to the Soil Quality Concept (Karlen et al., 1997): as an interdisciplinary discipline in itself, for its properties depend on chemical, physical, biological, hydrological and anthropogenic influences. Therefore, the theories used in this section have a rather interdisciplinary character.

The benefits people obtain from ecosystems are Ecosystem Services (Daily et al., 1997) - of which ‘agricultural food production’ is one (Burghardt, 2006). Ecosystem services are both a fundament for scientific research and for policy making (Hill et al., 2013). Therefore, the gained knowledge on ecosystem services does not stay in the scientific domain, but is directly used by politics to make policies that influence the society.

By looking at salinised fresh-water based agricultural sites as areas with ecosystem services, it is possible to regard the areas as systems with a certain Resilience (Holling, 1973). A socio-ecological system has different components with their own system resilience (Lal and Steward, 2013). By acknowledging their relation, understanding between disciplines can be created. Short-term anthropogenic influences may have a shock-effect on soils which cannot be stabilized. Creating mutual comprehension clears the way for potential common solutions for resilience-related issues.

THE FARMER

The Farmer is an important actor in the process of elevating the tipping point and determining whether the SAS is healthy or not. Within the SAS, the farmer can both influence the farm, and be influenced by institutions.

Farmers have common patterns of behaviour, for example in sharing a primary motivation of ‘good farm management’ (Vanclay et al., 1998). Since culture is defined as “the learned and shared knowledge that people use to generate behaviour and interpret experience” (Spradley & Mcurdey, 2012, p. 2), we can refer to the farmers shared patterns of behaviour as the farmers’ culture. This farmers’ culture is crucial when researching the farmers’ attitude towards SA.

Additionally, their behaviour can be investigated by means of the Transtheoretical Model of Behavioural Change (TTM). This method was originally developed to assist individuals in changing behaviour health patterns towards new healthier behaviour (Proschaska et al., 2008). However, the theory has extensively been extended (Repko, 2012, P.340) by researchers to provide insights in other disciplines, such as in stimulating sustainable patterns of food consumption (Tobler et al., 2011). In this

research the model will serve as a framework in researching how the implementation of SA can be facilitated, both from the perspective of the Farmer as the Institutions. The TTM assumes that people move through five stages: the precontemplation stage, the contemplation stage, the preparation stage, and finally action and implementation. It assumes that, in order to effectively stimulate change, stage-targeted interventions are required (Prochaska et al., 2008).

THE INSTITUTIONS

Institutions are the other actor in elevating the tipping point, they can facilitate the implementation of a transition to SA. The role of institutions within the SAS are made explicit using three concepts: Policy Communities, Transition Theory and Public Management.

Because of conflicting interests, societies have become increasingly complex and ambiguous(Noordegraaf, 2008). This makes it hard to understand how decisions in a certain policy area are made. However, there is some organisational structure, policy communities. These are composed of the subset of actors who are concerned with the same policy area. Some actors may be specialists or politicians, others are academics, consultants or analysts for interest groups. A policy community may be concentrated or fragmented, may share a common vocabulary, and can change over time (Kingdon, 2002). The policy community influences the decision making process.

The second concept is Transition Theory, as developed by Rotmans, Loorbach, and Geels among others. This field of science studies long term structural change from a systemic point of view (Rotmans and Loorbach, 2010). A useful insight of transition theory is the multi-level perspective. Research has shown that there are three separate levels in society: landscape, regimes and niches (Geels, 2002; figure 5). The landscape refers to the overall setting in which the transition takes place. The regime refers to the level of dominant actors, the institutions, rules and technologies that prevail within a system. The niches provide space for experimentation and innovation on a small-scale level, which can facilitate the interactions between actors that stimulate innovation (Geels, 2002). The multi-level perspective thus adds insights to the dynamic interaction within the SAS.

The final concept is Public Management. A complex and ambiguous societal landscape makes public management a necessity (Noordegraaf, 2008, p.26). Public management will be defined as ‘the ability of public institutions to influence joint efforts’. According to Noordegraaf (2008) institutions can select the most effective public management approach based on the landscape of the policy area.

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EFFECTS

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SOIL

SALINISATION

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Salinisation will impact socio-agricultural systems (SASs) around the globe. SASs in The Netherlands will be confronted with saline water and saline soils severely due to its location neighbouring the North Sea. In this section, the effects and impact of salinisation in The Netherlands is discussed.

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Two related questions will be approached as a literature research from the different disciplines’ perspectives. Firstly, what are the effects of primary soil salinisation on soils and agriculture? Secondly, what are its (indirect) effects on Dutch society? Together, they form a picture of the impact of primary soil salinisation on socio-agricultural systems.

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Soil salinisation is the process that involves the increase of dissolved ionic compound (salts) in the soil root-zone, via intruding saline water or evapotranspiration of groundwater and accumulation (caused by lacking water infiltration) of remaining salts from the water. Thereby, the soil salt

concentrations increase which leads to an alteration of soil(biota) characteristics (Hanson et al., 1999). The salts can be composed of the following cations: sodium, calcium and magnesium and the following anions: chloride, carbonate and sulphate (Rozema, 1996).

Two types of salinisation can be distinguished: primary and secondary (Breckle, 2009). Primary salinisation is caused by natural conditions and processes. According to Ondrasek et al. (2011), it can be caused by dissolved soil parent materials with high salt concentration; saline water entering terrestrial coastal (seepage or flooding) or inland (fossil salt aquifers) areas; aeolian seafoam with a high salinity blown landwards (figure 6 and 7). The forecasted rising of the sea level due to climate change will probably lead to a global increase of primary salinisation (Solomon et al., 2007). Secondary salinisation, in contrast, is anthropogenic. For it generally occurs in (semi-)arid climates (Breckle, 1989, referred to in Breckle, 2009, p.187), this research is focussed on primary salinisation.

EFFECTSON SOILSAND PLANTS

Salinisation can alter default soil properties. Salt-cations tend to replace the cations in clay mineral-complexes and enter the secondary clay minerals where they detach the clay lamellae sheets (Ondrasek et al., 2011). The clay minerals are being ‘disconnected’, inducing clay dispersion. Rainwater causes the clay to leech and illuvate in a deeper soil layer. Becoming impermeable (Burrow et al., 2002). The dispersed clay can also form a surface crust, inducing higher surface water runoff and thus soil erosion (Ondrasek et al., 2011). In addition, the desorption of clay minerals may lead to the mobilisation of toxic cations (metals).

Resulting from these chemical soil-alteration, biological properties can change as well. Soil biological processes decrease with salinisation, for soil microorganisms are sensitive for salinity (Ondrasek et al., 2011). This induces a decreasing organic matter decomposition and less nutrient-transformation. For example, it may decrease nitrogen fixation due to a decline of rhizobia leading to nitrogen deficiencies (Bhardwaj, 1975). Furthermore, salinity reduces the water uptake by plants roots, causing water deficiencies in plants (Brouwer et al., 1985).

Therefore, these effects of salinisation decrease a soil’s suitability for agriculture. Salinity is proved to cause a decrease in agricultural yield of 10% with a salt concentration increase of 1 dS/m (Scardaci et al., 1996).

Globally, approximately 4 million square kilometer of the land is prone to salinisation (both primary and secondary) worldwide (FAO, 2005, referred to in Rozema & Flowers, 2008). Since 70 percent of the land surface of The Netherlands is agricultural ground, salinisation is expected to impact the Netherlands strongly.

EFFECTSON FARMERS AND INSTITUTIONS

Evidently, primary salinisation will affect human society in the long run. Although less predictable than the effects on soils, plants and agriculture, some hypotheses can be made. If not acted upon, salinisation will decrease the output of farms, which will reduce the income of farmers. In turn, this could lead to a decrease in the amount of farms, which may lead to a declining population of the local rural community. On a more personal level, families affected by this change are vulnerable to higher levels of stress and possible health problems (Pannell, 2001).

Furthermore, declining farm outputs will increase the price of food. History has shown that higher food prices may lead to demonstrations and uprisings (Stone 2012).Salinisation will thus have an impact on the functioning of institutions. According to Stone (2012)political institutions are only legitimate if they act in accordance with the needs of the population they aim to represent. The possible instabilities in local rural communities are a substantial reason for institutions to act.

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Primary soil salinisation does affect both physical soil properties and soil microbial life. Soils become less fit for agriculture as it is currently practiced. The declining production resulting from this also affects the rural community in terms of population, economics and health. According to De Boer and Radersma (2011), one of the possible ways of coping with soil salinisation, is making a transition from ‘conventional’ towards saline agriculture. The sequel of this research will study the possibilities of the implementation of this cultivation method.

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The research will focus on a specific area in The Netherlands, from which the feasibility of saline agriculture and its implementation will be studied. The results from this case-study can, in their turn, contribute to more general knowledge about salinity and saline agriculture in the entire Netherlands.

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This specific area has to comply with certain criteria. Firstly, it should be prone to primary soil salinisation presently and in the future. Secondly, ‘regular’ agriculture in the area should be negatively affected by this salinisation. Based on these criteria, the case-study area will be chosen by a literature study of scientific data, maps and forecasts.

CRITERION 1: A SALINISATION-AFFECTEDAREA

Oude Essink and Van Baaren (2009) have mapped the present salinity of the Dutch subsoil, using

soil chloride concentration as measurement. Figure 8a displays the current (2000) chloride concentrations in the groundwater of The Netherlands, whereas figure 8b displays the expected concentration in 100 years. Some sites will experience a significant increase of groundwater salinity and will thus in the future be at risk of severe salinisation. Therefore, an already salinised area with a

future higher salinisation risk (red in figure 9), will be used as case-study area.

CRITERION 2: NEGATIVE IMPACT ONAGRICULTURE

According to De Boer and Radersma (2011), some agricultural areas of The Netherlands will be affected more than others. For example, North-Holland will indeed become highly salinised, but its agriculture will not be hit severely. This is caused by the fact that water-soil salinity and freshwater supply do not fluctuate much here, and the common crops in the area are relatively salt tolerant.

However, South-Holland’s agriculture is said to be put at risk by salinisation (De Boer and Radersma, 2011). The province will experience highly fluctuating salt-concentrations. Summer peaks of salinity will become common, if summer river discharges decrease by climate change. Furthermore, originally cultivated crops are salt-sensitive. Agricultural will already be negatively affected here by small salinity-increases.

THE CASE-STUDY AREA

Therefore, this research will focus on a case-study in South-Holland. Figure 9 shows that a zone in the western part of the southern island of South-Holland (Goeree-Overflakkee) will have a high salinisation increase. This area is therefore selected as case-study location.

SALINISATION ON GOEREE-OVERFLAKKEE

Goeree-Overflakkee is surrounded by (sea)water and therefore expected to be prone to primary salinisation. Historically, two main causes of salinisation can be distinguished in The Netherlands (Ter Voorde & Veldstra, 2009). Firstly, direct seawater flushing and seepage. Secondly, land reclamation and the subsequent ground subsidence allowed Holocene salt groundwater to move up to the surface soil.

Today and in the future, Dutch salinisation will mainly be caused by the rising sea level leading to both internal and external salinisation. Internal salinisation is characterised by seepage intruding the surface soil through the ground. External salinisation is caused by rivers with a lowering discharge (because of a warming climate) that get salinised by entering seawater, and in their turn salinise the soil. Currently, the main salinisation-type on Goeree-Overflakkee is internal (seepage, figure 11). In the future, a rising sea level might make the surrounding fresh waters Haringvliet and Volkerak-Zoommeer brackish or salt, resulting in additional external salinisation (De Vries et al., 2011).

One method to describe salinisation on Goeree-Overflakkee is the ‘salt-load’ (seepage flux * chloride concentration). The island’s salt load is relatively high because of the high seepage chloride concentration - at the case-study location, seepage salt concentrations exceed 10.000 mg Cl-_{/L (De}

kg/km2/year. Under a >2° Celsius temperature rise this will increase with a maximum of 61% in 2050, thereby causing Goeree-Overflakkee to salinise (Oude Essink et al., 2008).

Figure 12 reveals that the case-study zone consists of clay-soils whereas its surroundings are sandy-soils (Alterra, 2005). This is related to the fact that this zone is expected to be prone to higher salinisation-levels than its surroundings. Clay-soils generally have a higher saturated soil salinity than sandy soils (Lü et al., 2012). This is possibly caused by their lower infiltration rate (in sandy-soils salts are being flushed by fresh water) and their higher cation exchange capacity (salt ions are retained by clay-minerals).

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As case-study area, a specific zone in the western part of the island Goeree-Overflakkee is chosen. The case-study area will be used for literature and empirical research from the Farm and Farmer perspective in the sequel of the research in order to investigate the possibilities of saline agriculture. The case-study will be used as an example for the bigger scale, with the awareness that it will not represent the entire Netherlands.

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In the case-study area

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Van der Greft-van Rossum et al. (2012) have studied the proximity of an ecological tipping point on

Goeree-Overflakkee. It is revealed that the case-study zone is currently and under every future climate scenario ‘very near’ to a tipping point for

‘agricultural nature’. Therefore, changing towards SA might entail the needed system transition that uses the saline conditions and gives the system a ‘new’ resilience. In this section, the feasibility of SA in the case-study area will be researched.

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In order to reveal the possibilities of SA in the area the possibility of an agricultural transition within the different components of the socio-agricultural system should be taken under the loop. Considering the Farm-aspect, Literature research is done to reveal what biochemical properties are needed for SA and what crops can best be cultivated regarding SA. Fieldwork is performed in order to analyse the soil chemical properties of a field located in the case-study area.

Secondly, the “farmers’ culture” and their willingness and ability to perform a transition towards SA will be studied via literature research and fieldwork: conversations with the farmers themselves. Together, this will

attempt to answer the question whether SA is feasible in the case-study area.

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SOILPROPERTIES FOR SALINE AGRICULTURE

Saline agriculture is basically the cultivation of crops on saline soils or with saline irrigation water. It can be performed 1) if soils have a certain salinity and 2) by cultivating salt-tolerant crops. In principle, a soil is considered as ‘saline’ when its EC is >2dS/m.(Abrol et al., 1988). However, plant growth is generally already affected from 1,4 dS/m (Blaylock, 1994). Therefore, SA might be feasible from this salinity on. In addition to the saline requirement, a soil should meet the regular fertility-requirements.

CROPSFOR SALINE AGRICULTURE

The evolution of Earth’s plant species started in saline ocean water. Therefore, the majority of current plant species began its evolution as halophyte plants- that need or tolerate a certain salinity in the soil. However, most plant species lost their saline adaption when evolution continued in freshwater terrestrial systems, resulting in a current amount of halophyte plants species of only 1% (Rozema & Flowers, 2008).

A distinction can be made in salt-tolerance of plants: glycophytes (‘sweet-loving’), intolerant halophytes, facultative halophytes and obligate halophytes (‘salt-loving’) (Barbour, 1970). The latter experiences an optimal growth rate in saline conditions. Varying cation-anion compositions influence plants growth rates, but preferences for the composition differ per plant.

The physiological difference between glycophytes and halophytes regards the way they handle salt ions. Glycophytes tend to exclude salts from their leaves and transport them to the root-system. If this process fails, salts are accumulating in the shoot-system and growth is reduced. Halophytes, on the other hand, use the accumulation of salt in their leaves and are able to retain a high cell-water content despite of the low external water potential in saline surroundings. This enables them to cope with high salt concentrations without wildering from osmosis outwards the plant (Flowers et al., 1977; Flowers & Colmer, 2008).

The difference between facultative (FH) and obligate halophytes (OH) is essential with regards to saline agriculture. OH’s need saline conditions for an optimal growth, while FH’s are tolerant to salinity but do not require it physiologically (Barbour, 1970). FH crops grow well in fresh water agriculture but can tolerate moderate salinity (Grontmij, 2010). Saline agriculture can be suitable for both OH and FH crops. Typical (low-yield) OH’s are samphire and seaweed. Typical FH’s are sea kale, barley and beetroot (Grontmij, 2010). The general salt-tolerance classes of crops (where OH’s and FH’s find themselves in the ‘Moderately

tolerant’-‘Tolerant’ class) is:

In the case-study zone, flower bulb-, fruit tree-cultivation and horticulture will be disturbed by salinisation most (Provinciale Staten van Zuid-Holland, 2009). More specifically, potatoes, onions, carrots and decorative pumpkins are cultivated here. In order to reveal the possibility of saline agriculture in the case-study area, fieldwork and soil analysis were performed with the leading questions: will SA be necessary in the case-study area (salinity wise) and are the current soil properties feasible for SA? FIELDWORK: METHODOLOGY

The sampling field was a fallow field with green manure. Unlike its surrounding it was not recently ploughed, making it more suitable for sampling.

A brief methodology is given below.

FIELDWORK: RESULTS AND INTERPRETATIONS (APPENDIX 5)

Agricultural side-conditions: Loss on ignition and pH

The loss on ignition-test revealed that the average loss on ignition (and thus the approximate organic matter content) of the field is: 1,42 %. The average of the A-zone (15-25 cm depth) is slightly higher than that of the B-zone

(40-50 cm depth): respectively 1,67 and 1,16 %. This is considered as a relatively low organic matter content and thus probably a relatively low field fertility.

In addition, the average field pH is relatively high: 8,00. It is therefore slightly basic. This might be caused by the field’s nearness to the coast and the subsequent CaCO3 supply (Ca2+_{-concentration, Appendix 5) or by the}

basic properties of seawater (Hall-Spencer et al., 2008). Electronic Conductivity

The average EC of the field is 0,098 dS/m. The average EC of the A-zone is 0,097 dS/m, whereas that of the B-zone is slightly higher: 0,099 dS/m. This reveals that the salinity probably indeed is internal and thus caused by seepage coming from deeper ground layers. In general, the EC is relatively low. Salinisation is currently not occurring - it is typed ‘salinisation’ from 2dS/m (Abrol et al., 1988). Therefore, SA is not needed here at present.

When looking at the currently cultivated crops in the case-study zone, it is noticeable that they are sensitive for saline conditions. Pumpkin and potato is classified as ‘moderately sensitive’, and onion and carrot as ‘sensitive’ (Blaylock, 1994). Therefore, from a soil-EC of 2,7 respectively 1,4 dS/m, the crop-yield will be negatively affected (table x). The current soil-EC is lower than this. However, Oude Essink and Van Baaren (2010) expect the salinity in this zone to be increased with 2000-5000 mg Cl-_{/L in 2050.}

Converted, the approximate EC is expected to be 7,9 dS/m in 2050. The calculation is simplified by assuming that the Total Dissolved Salts is only composed of the measured ions (causing the EC to be overestimated):

At this salinity-level, the default crops will not be able to grow in the zone anymore. A transition towards saline agriculture may be needed to keep agriculture running. The expected soil-EC would be best suitable for salt (moderately-) tolerant crops (Blaylock, 1994).

Ion composition

Different conclusions can be drawn from the ion-composition analysis. Firstly, both the Na+ _{and Cl}-_{concentration are remarkably lower in the}

layer than in the A-layer (both approximately halved), whereas the other ions’ concentration is approximately equal in both layers (graph 1). This is contradictory with the expected higher B-layer concentration caused by seepage. There are different explanations. For the macro-nutrients nitrate, nitrite and phosphate show a similar trend (graph 2), it might be caused by artificial fertiliser (containing NaCl like kali-salt or fertilising-salt) that did not infiltrate the B-layer. However, further research is needed to reveal the exact cause.

The soil ion-composition will influence the crop choice. In the scope of this research, crop salt-tolerance is given priority. In that manner, possible FH’s -with a higher yield than OH’s- are: rye (EC-threshold 11,4 dS/m),

rapeseed (EC-threshold 11 dS/m), barley (EC-threshold 8,0 dS/m), and sugar beet (EC-threshold of 7,0 dS/m) (Bower et al., 1954; Francois et al., 1989; Francois, 1994; Hassan et al., 1970). However, future crops should not only be (moderately) salt-tolerant, but also be able to cope with a high pH, a high Ca2+_{- and Cl}- _{and clay-content, a low organic matter content and}

a temperate climate. If these crops also comply with these requirements, they all would be suitable here. Further research should reveal this. More specifically, it is known that especially barley (Hordeum vulgare L.) thrives in Ca2+_{-rich soils (Grontmij, 2010). This might be a reason to decide on}

cultivating barley as a crop for a saline future on Goeree-Overflakkee.

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In this section the farmers’ culture will be investigated from a theoretical and empirical point of view. We will elaborate on the factors that influence the decision making process of farmers when confronted with the option and/or necessity to change, and apply this to SA.

METHODOLOGY

Since adaptation is based on subjective perceptions rather than an objective truth (Pannell et al., 2011) it is vastly important to acquire information through both a literature study as conversations with the farmers themselves. The limited time span allowed to approach 15 farmers, of which we managed to talk to five. The questions asked can be divided in two subcategories: 1) questions directed at the farmers behaviour and perspective on change towards new practices in general 2) questions concerning SA specifically.

It must be stressed that these conversations and the obtained insights should not be seen as a representative sample for the farmers on Goeree-Overflakkee nor in the Netherlands. Rather the aim is to both get a general feel of the behaviour and attitudes farmers share and their awareness and worries around salinisation and SA. For an elaborated script of the conversations and research questions see Appendix 1 and 2.

RESULTS

Goals

According to Pannell et al. (2011) several decades of research have made clear that landholder acceptation of a new practice mainly depends on the expectation whether it will allow them to better achieve their goals(Pannell et al., p 1408). The goals that the farmers brought up were: to be able to make a living of the farm, to overcome challenges, to extend, and to be able to continue the existence of the farm. Money was not seen as a goal on itself, but as a necessity to live. In general, farmers farm simply because they love the lifestyle. Since it regularly occurs that a farm has been in the hands of a family for many generations, it is no surprise, that overall, the main goal was to be able to carry on with the farm (Appendix 2). Obviously, 28

this attitude results in a greater openness to practices which allow farmers to continue despite the changing circumstances, such as SA.

Furthermore, adaption is based on three issues, being the learning process, the characteristics of the specific farmer within his own social environment, and the characteristics of the practice itself (Pannell et al., p. 1408).

The process of learning and experience

Literature stated that farmers take educated thought-through decisions, based on the collection and evaluation of information from scientific, personal experiences and cultural influences. In the conversations it became clear that farmers are mostly experience-based. Farmers stated that in changing practices, they would ask other farmers and further trial out themselves. This is important to mention, since it implies that practices for which an experience-based approach is suitable, will be more feasible. It will become clear that this is the case for saline agriculture in more detail in the section ‘characteristics of the practice’.

Characteristics of the Farmer

When considering new practices, the farmer often operates as a part of larger team. Especially in the case of risky decisions with important consequences, farmers turn to community and/or family support in the process of decision making (Pannell et al., p. 1410), making the attitude of the larger community an important factor in the feasibility of saline agriculture. The conversations affirmed that farmers attach great value to what other farmers think and do. Of course, a share of the farmers will always be on the look-out to distinguish themselves from other farmers and bring something new to the market. As one of the interviewees stated: “it has often occurred that we started something which no one else was doing yet” But in those cases, it doesn't take long before the rest follows: “The other farmers see this novelty work, and after 4,5 years, there’s nothing new about it anymore”. The conversations made clear that as soon as one farmer in the community switches to saline agriculture, the others will follow fairly quickly if they see it working.

Characteristics of the Practice

When investigating the attributes of the practices which affect the adoption of innovations, three main categories can be distinguished: The relative advantage and the trialability of the innovation and finances (Pannell et al., p.1414)

With triability we refer to both the ease of physically establishing a trial and the ability to learn from a trial. Triability has been appointed to enhances adoption (Ohlmer et al., 1998), as it reduces uncertainty. A high triability encompasses several factors. First of all, a degree of divisibility is crucial. in other words, it needs to be adaptable on a small scale (Leathers & Smale, 1992) or needs to be able to be implemented stepwise (Wilkinson, 1989). In the case of SA, farmers can start with a small plot and slowly transit to saline crops. It became clear that farmers already have a tendency to do small-scale experiments with new breeds, starting on a small plot and expending the next year if proved effective. Since SA is mostly a matter of trying out a new breed too, and can be easily implemented gradually, we can assume the threshold for farmers to try out salt resistant crops won’t be high. Furthermore, triability increases with the observability of 30

results(Pannell, 2001). If rapidly and easily observable, it is easier to learn from other farmers (Geroski, 2000), which is important since we have seen that farmers are mainly experience-based. In general, Production-orientated practices such as SA, are easily observability (Pannell et al., p. 1417). It may be clear that, compared to groundwater management, SA has a much shorter lag between implementation and results, and is thus also relatively rapidly observable. However, we want to argue that saline agriculture is also objectively seen, rapidly observable. This becomes clear in the farmers’ perception of time. The farmers defined their work in terms of farming cycles: from preparing the soil to selling, repeating the same cycle the next year. The farmers’ unit of work is thus one year, and they tend to both think and make plans in terms of this unit. Secondly, 4 out of 5 farmers we talked to saw the farm as a project of a lifetime, or even transcending generations. In this light, one cycle is seen as relatively short. In this light, farmers added that one bad year is still manageable, as they are constantly prepared for this anyway.

The role of costs of a certain practice in decision making processes is highly debated. Mostly, money it is seen as an important aid to achieve ones goals(Pannell et al., 1411). We remarked some worries centred around the theme of economic feasibility of SA. One farmer expressed worries about the type of crops: “I grow 80 hectares of sugar beets, on an area that large, those samphire type crops cannot really compensate for the sugar beets”. Another farmer was worried about a saturated market. “If everyone on Goeree-Overflakkee starts to grow samphire, how will this affect market prices?” These concerns decrease SA’s feasibility. However, one farmer pointed out that an added value could make the crops profitable. Spelt and barley for example, are becoming more and more popular as a healthy alternative to wheat, which might increase their market value. Furthermore, a greater variety of high yielding saline crops might also diminish these worries. In this way, farmers can choose for the crops that best suit their needs, and there would less competition.

With relative advantage we referred to the degree to which an innovation is perceived as being better than the idea it supersedes (Rogers 2003, p.229), based on economic, social and environmental profits in the medium-to-long term (Pannell et al, p.1414). Since none of the farmers encountered problems with salinisation yet, it is hard to get their perception of the relative advantage SA might bring. We can however, say something about whether SA is perceived as being a better idea than trying to combat salinisation by means of conservation practices. Here we found an interesting paradox. Goeree-Overflakkee has been taking preventive measurements for a long time, and has consequentially developed a combined identity of being technically highly developed, and able to combat salinisation and retain the great soil, as a result of this. Farmers on Goeree-Overflakkee are proud of their soil, and want to keep it. This would imply

that they would turn to conservation methods more easily than to adaptation practices such as SA. However, we also noticed that , farmers are rather pragmatic, acting upon problems when they actually become a problem. Even though they all stated that hopefully salinisation will never be an issue, the whole subject seemed to be too ‘invisible’ , ‘far away’ and ‘complex’ for them to even think about taking preventive measures. Conservation seemed to be only an option if the government took initiative.

S

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It can be stated that the results from the empirical research from the farm and the farmers are interrelated. This becomes clear in table 1.

From the perspective of the farm, SA in the case-study area is found to be both possible and needed. The agricultural side-conditions (pH and OM) are not ideal yet workable. Therefore, if salinity-levels increase to a level where saline crops can be cultivated, SA will be feasible. However, soil analysis revealed that the case-study area is not saline at present. Likewise, farmers stated that they did not notice any negative effects yet, which is the main reason most farmers did not even think about saline agriculture yet. Yet, when adding the expected salt-increase (Oude Essink and Van Baaren, 2009), the soil-EC exceeds the salt-tolerance of the default cultivated crops, making SA needed in the future. From the perspective of the farmers in the case-study area, SA has a high feasibility. It is highly observable and divisible, and therefore has a high triability, which makes it an attractive option.

Furthermore, even though the farmers would prefer to prevent salinisation rather than turn to adaptation practices, they paradoxically enough do not undertake preventive measurements themselves. If governments fail to do so, SA is a more likely option than prevention. The yield of the crops was determined as a main concern of farmers. Therefore, there should be a focus on a variety of high yielding facultative crops. With regards to the ion-composition, agricultural side conditions, and profitability barley might be the best suitable crops to cultivate in the case-study zone. These are valid results for the chosen SAS. However, it must be noted that the properties of the case-study area will differ from other SASs. Therefore, the feasibility of SA should always be researched by means of a SAS-specific approach.

T

HE

I

MPLEMENTATION

OF

S

ALINE

A

GRICULTURE

With a focus on the case-study area

I

As revealed by the previous research sections there is a strong indication that Goeree-Overflakkee will be highly salinisation-prone in 2050. Furthermore, it was revealed that the soil characteristics are most probably favourable for saline agriculture, and farmers indicated that they are willing to change if necessary. A transition to saline agriculture is thus possible, although implementation should be taken into consideration. The term implementation is defined in this report as the whole process that ranges from creating awareness for a possible solution to a certain problem to the practical establishment of the solution, resulting in the continuous functioning of a new system.

To address the process of implementation, we propose to use the Transtheoretical Model of Behavioural Change (TTM) as a framework. The different stages of the TTM accurately capture the process from creating awareness to the continuous functioning of a new system. Evidently, we focus on how saline agriculture can be implemented to benefit the socio-agricultural system (SAS), taking the situation of Goeree-Overflakkee as example. This section will focus on Farmers and Institutions, as these actors of the SAS are concerned with the process of implementation. It is argued that stage-targeted facilitation is essential.

M

Insights from Political Science and Anthropology will be used to address factors of importance in the process of implementation. To investigate the implementation process of saline agriculture from the perspective of farmers, we conducted a literature study and had conversations with 5 farmers. These conversations were aimed at gaining insight in which stages of the TTM the farmers are in. From the institutional perspective a literature study has been conducted to investigate how the process of implementation can be facilitated by institutions. Because the scope of this report is limited, case specific recommendations will not be made explicit.

F

Regarding the implementation it is crucial to turn to the farmers, since they are the main actors in the SAS. As explicated in the theoretical framework, the first priority is to allocate the farmers to a certain stage of development within the TTM. The TTM assumes that people move through five stages during a transition (Prochaska & Velicer, 1997; Prochaska et al., 2008). 34

When the stages of farmers are identified, the process of implementation can be facilitated by institutions.

Precontemplation Stage

The first stage is the precontemplation stage. In this stage a lack of information about salinisation leads to no intention of taking action to change farming practices in the near future.

In case of the SAS on Goeree-Overflakkee,three of the five farmers we talked to were in this stage. When asked upon, these farmers affirmed they had heard about salinisation, but stated not to think about it so much, nor would they have conversations with other farmers about it. Probably, these farmers have not heard about salinisation so much yet, which might lead to an underestimation of the severity.

Institutions can facilitate the precontemplation stage with information management, among others defined by Noordegraaf (2008). This management approach includes informing the actors about the risks of a certain problem. Setting up knowledge networks and conducting research are alternative strategies. In the case of salinisation on Goeree-Overflakkee, institutions should definitely focus on information management since three of the five interviewed farmers are in this stage.

Contemplation Stage

In this stage, there is an intention to respond to the salinising environment. Farmers will now consider the costs and benefits of different solutions. These different solutions, such as saline agriculture, or solutions directed at soil and water management, are compared.

Two of the five farmers did not have an immediate intention to change, but took the possibility of salinisation seriously and were already contemplating possible solutions.

The contemplation stage is very similar to the process of agenda setting. Some solutions never make it to the policy agenda, which indicates that this process is also about the comparison of ideas. Agenda setting is important because public institutions only support policies that are on the policy agenda. In the case-study saline agriculture is still competing with other solutions, recent policy proposals to address salinisation on Goeree-Overflakkee are mainly focusing on prevention of saline water intrusion (Wateragenda Zuid-Holland, 2012).

For the facilitation of the contemplation stage it is thus needed to analyse the process of agenda setting. In this report the Stream model of Kingdon (1984) will be used because it accurately captures the complexity of the agenda setting process. This model is prefered over other, more rational models because in practice policy making is far from rational (Stone, 2012, p.250). According to Kingdon (2002) there are three independent processes (streams) that are important for agenda setting: problem recognition, policy proposals and political events.

To understand why some solutions are preferred over others it is needed to analyse the policy stream. Using the concept of policy communities (as defined in the theoretical framework) it is possible to analyse the policy stream, where solutions for problems are debated. Once the policy community agrees that one solution should be favoured (often influenced by practitioners in the field) the solution will appear on the policy agenda.

In the case of Goeree-Overflakkee, institutions can facilitate this stage in two steps. First of all, it is needed monitor the actors within the agricultural policy community. Secondly, it is needed to convince the majority of the actors that saline agriculture is the best possible solution. This will increase the chance of agenda setting. It should be clear that the facilitation of this stage is very case specific and that different strategies could be employed.

Preparation Stage

Here, farmers intend to take action in the near future, and they even have a concrete plan at hand of how to deal with the problem of salinisation.

We did not encounter any farmers who were in the preparation stage or further stages, and none of the other farmers they spoke about seemed to fit in these stages either.

In the preparation stage, the role of institutions should be aimed at providing subsidies and funds to stimulate the transition to SA. In doing so, institutions are automatically facilitating the subsequent stages. From the conversations on Goeree-Overflakkee it became clear that farmers are mainly concerned about the profitability of their yield if they change to SA. Providing subsidies and funds could give farmers the incentive to start making concrete plans.

Action and Modification and Implementation Stage

In the fourth and the fifth stage the farmers actually change their previous practices and the practical implementation occurs. The new practices is adjusted until finally it is fully integrated and working in the farmer’s business.

The final stages are all about putting SA into practice. The practical implementation is carried out by farmers, therefore these stages do not require any institutional facilitation.

N

S

S

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There are other important factors which are not stage-specific. First of all, it is important to encourage a participatory process (Marsh 1998) between the researchers and the farmers. Interaction increases the farmers’ knowledge of the practice, and with this also his or her sense of ownership and faith (Pannell et al.,2011). Also, beneficial practices which are already being done, such as community discussions, should be encouraged (Marsh, 1998). In such a way participation helps to develop better programs and recommendations, by making use of local knowledge (Marsh, 1998).

A suitable public management approach that follows from transition theory. This approach is called strategic niche management. This approach argues that new technologies and innovations are at first relatively crude and inefficient because they are badly adapted to their ultimate uses and their environment (Schot and Geels 2010). Because of this, innovation should be stimulated by actively creating niches in which experimentation with technology, user practices and regulatory structures is possible. According to Schot and Geels (2010) this cannot be accomplished top-down, but must be done by steering from within the niches and engaging a broad range of actors. The niches ideally consist of farmers who are in the final stages of the TTM. Successful experiments could be scaled up to benefit the rest of the SAS.

S

-

It can be concluded that during the process of implementation, facilitation should respond to what stage in the TTM the farmers are in. The public management approach should respond to the needs of the local people. In the case of Goeree-Overflakkee three farmers were in the precontemplation stage, and two farmers in the contemplation stage. It can thus be stated that the farmers are still in early stages of change. It should be noted that each SAS in the Netherlands is unique, farmers might be in different stages, facilitation should therefore respond to the landscape of each SAS. The stage specific results are summarised in table 2. Non stage specific results point out that a participatory implementation process is needed. A public management approach that recognises this need is strategic niche management.

C

ONCLUSION

This research has investigated how the implementation of saline agriculture can contribute to resilient socio-agricultural systems in the Netherlands. To be able to continue its ecosystem service of agricultural production despite of the external salinisation-disturbance, the tipping point of the landscape should be elevated. In order to investigate whether saline agriculture can raise this tipping point, the research has focused on the case-study of Goeree-Overflakkee from the Farm, Farmer and Institutional perspective, which together form the socio-agricultural system (SAS).

From the Farm-perspective, empirical and literature research revealed that -even though the soil is not salinised yet- the currently cultivated crops in the case-study area will not be able to grow there under the expected future salinity increase of approximately 7,9 dS/m. Considering the overall soil-state, saline agriculture will be possible in the future. Suitable salt-tolerant crops might be rapeseed, rye, barley and sugar beet. However, the crops should also be able to grow under other soil-specific condition. Taken this in consideration, barley is recommended as future crop.

From the Farmer-perspective it became clear that salinisation is not yet a worry, since negative effects are not visible. However, if salinisation occurs, most farmers would be open to apply SA since it has a high triability. One precondition is economically feasibility. Crops with an added market value, such as barley, will be favourable.

From the Institutional-perspective, the transition to saline agriculture can be facilitated in various ways. Since the farmers are the focal point in the transition, strategic niche management turned out to be the most suitable management approach.

Taking the results from the case-study as a starting point, different conclusions can be drawn concerning saline agriculture (SA) in the entire Netherlands. Firstly, one could state that the Netherlands is a composition of various SASs with their own particularities and similarities. This makes that basic principles can be applied to all SASs. Paradoxically, the overarching similarity between the different SASs is their need for a focus on locality. Since each SAS has different properties, a SAS-specific approach is required. Secondly, a large crop-diversity is needed to comply with the Farm- and Farmer-properties. Different soils and goals of farmers, require a large choice of possible saline crops. Facultative halophytes are preferable because of their high yields.

In the case-study area, farmers were still in the precontemplation and contemplation stage of the TTM. However, in the entire Netherlands,

farmers will be scattered over all five stages. A stage-targeted approach will be need in order to facilitate the implementation of SA in the Netherlands. Furthermore, by means of strategic niche management early-staged SASs can learn from later-staged SASs. In this way, a network between the separate SASs that undertake the transition to SA is created. This might stimulate the creation of awareness amongst early-staged SASs.

It also turned out that farmers tend to only act when problems become visible. Since many soils are not yet salinised, but expected to be in the future, this might be a crucial reason to stimulate SA, elevate the tipping point and increase the SASs’ resilience to primary salinisation. Arising out of this, a SAS will benefit from being aware of its three components. If the components are conscious of being in a constant dynamic relation, the SAS as a whole will be better armed against external disturbances, such as salinisation. This might increase its ability to make the right choices that enable the SAS to maintain a healthy, sustainable state.

D

ISCUSSION

Evidently, the report has limitations. First of all, in researching the feasibility of saline agriculture, the economic feasibility is also vastly important (both macro and micro-economics). This aspect of the feasibility is beyond the scope of this research, but is recommended for follow-up study. Secondly, it is needed to investigate other cases in the Netherlands. The case of Goeree-Overflakkee has been analysed, yet this case-study is not a representative for the rest of The Netherlands. It has served as an example to analyse general lessons which can be applied on other cases, but more case-specific research on the feasibility and implementation of saline agriculture is needed too.

With regards to the empirical soil analysis, different important soil properties have been left out of the research for time-efficiency reasons. In further investigation, these soil characteristics (among others a total texture determination) should be performed. Also, a differentiation between the salt-tolerance of different plant growing stages could be made in order to make a more specific crop-recommendation. Furthermore, to get a more accurate idea of the local Farmer-circumstances, the conversations with the farmers should be elaborated. In order to ease the transition to saline agriculture, it is recommended to expand research into new facultative halophytes. In addition, since profitability is an important factor in the feasibility of saline agriculture, already existing research on the upscaling of saline agriculture(for instance on Texel) should be further developed.

An interesting idea for further investigation, is that saline agriculture creates the possibility for a more balanced relation between agriculture and nature. The salt conditions are beneficial for nature development. An 40

integration of saline agriculture and brackish nature might be a possibility for a saline future.

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