||»Agricultural University Athens (AUA)|
|Authors:||Constantinos Kosmas, Orestis Kairis, Chrysa Aratzioglou
|iSQAPERiS editor:||Jane Brandt|
|1. Videos and infographic|
|2. Study site description|
|3. Participation of stakeholders in the iSQAPER research programme|
|4. Research tasks|
|5. Long-term impact of iSQAPER's research programme in the study site|
Μια σειρά από σύντομα βίντεο και ένα γράφημα δημιουργήθηκε από την ομάδα της πιλοτικής περιοχής μελέτης της Κρήτης για να περιγράψει τα ζητήματα που σχετίζονται με την ποιότητα του εδάφους στην Κρήτη και τον τρόπο με τον οποίο μια σειρά από τοπικά χρησιμοποιούμενες πρακτικές διαχείρισης ωφελούν την ποιότητα του εδάφους.
A series of short videos and an infographic were made by the Crete study site team to describe the issues associated with soil quality on Crete and the way in which a number of locally used management practices benefit soil quality.
»Φυσικά χαρακτηριστικά της πιλοτικής περιοχής μελέτης iSQAPER στην Κρήτη, GR
»Physical characteristics of iSQAPER study site on Crete, GR
|»Παράγοντες που επηρεάζουν την ποιότητα του εδάφους
Η ποιότητα του εδάφους καθορίζεται από έναν αριθμό εγγενών ιδιοτήτων καθώς και από πρακτικές διαχείρισης που προκύπτουν από την ανθρώπινη παρέμβαση.
(στα ελληνικά με αγγλικούς υπότιτλους)
»Factors affecting soil quality
|»Πρακτικές διαχείρισης γης που προστατεύουν την Κρήτη από την υποβάθμιση, GR
Η ακαλλιέργεια ή η ελαχιστοποίηση του οργώματος μειώνουν την επιφανειακή απορροή του νερού και την απώλεια του εδάφους, αυξάνουν την αποθήκευση νερού στο έδαφος, αυξάνουν την περιεκτικότητα σε οργανική ύλη καταλήγοντας σε μεγαλύτερη βιοποικιλότητα και χαμηλότερο κόστος παραγωγής ελαιολάδου.
(στα ελληνικά με αγγλικούς υπότιτλους)
»Land management practices that protect Crete from degradation, GR
|»Πέτρες και χαλίκια (αδρομερή υλικά) και διατήρηση του εδάφους στην Κρήτη
Η παρουσία αδρομερών υλικών στην επιφάνεια του εδάφους έχει σημαντική επίδραση στη μείωση της διάβρωσης, με αποτέλεσμα την προστασία των εδαφών από την υποβάθμιση και την διατήρηση του εδαφικού νερού. Αυτό μπορεί να οδηγήσει σε αύξηση της παραγωγής των καλλιεργειών σε μεσογειακές κλιματικές συνθήκες.
(στα ελληνικά με αγγλικούς υπότιτλους)
»Rock fragments and soil conservation Crete, GR
»Πρακτικές διαχείρισης γης και απειλές εδάφους στο νησί της Κρήτης
»Land management practices and soil threats in the island of Crete
The study site of Crete is bordered to the north by the Sea of Crete and to the south by the Libyan Sea and covers an area of 8336 km2. The climate of Crete is generally described as mild Mediterranean with the annual rainfall ranging from 262 to 978 mm in the low areas, while in mountainous areas from 551 to 1836 mm with a potential evapotranspiration ranging from 948 mm to 1640 mm yr-1. Crete lies between the isotherms 18.5 °C to 19 °C with an annual amplitude of 14 °C to 15 °C. The island is characterized by sloping land with slopes >12% in 79.5% of the area, while only 6.9% is comprised of lowlands with slope <6%. Among the most important land degradation problems of Crete are soil erosion in the sloping land, chemical deterioration of ground water, and land desertification. The coordinates of the study site (coordination system: UTM-WGS – Zone 33 North) are: left: 452134.31250, right: 713874.3750, top: 3949935.0000, and bottom: 3864285.0000.
Main farming systems and typical agricultural management activities in the study area
Cultivated land covers 42.0% of the island, while dry land is used mainly as pasture as the next most important land use covering 39.3% of the island. Climatic and soil characteristics accompanied by EU policies on subsidizing crops in the last two decades, have greatly favoured the extensive expansion of olive and vine plantations in the area which provides farmers with higher incomes. Olive groves in Crete occupy an area of about 193,813 ha covering almost 23.3% of the island. The olive oil production in Crete is up to 150.000 tons per year. Orange plantations and vegetables grown in greenhouses have been mainly expanded in the lowland areas of the island. High amounts of fertilizers have been applied up until the last decade. However, farmers have realized the negative impacts on the environment and the increasing cost of crop production and thus the amount of applied fertilizers have steadily decreased. Drip irrigation has been expanded in the cropland areas to ensure increasing crop production. However, the over-exploitation of the aquifers has resulted in deterioration of water quality (high soluble salt content), thereby affecting soil salinization. The lack of good quality water has stimulated the construction of small reservoirs for increasing water availability for irrigation.
The intensification of agriculture resulted in accelerated rates of soil erosion in the hilly areas of the island. Furthermore, water pollution of the aquifers has become an important issue due to over-fertilization of the land and overuse of plant protection chemical products. Land desertification due to salinization in the lowlands and due to soil erosion in the sloping areas has become an important issue. Organic farming and integrated land management practices have been established in some areas for the protection of soil quality and ecosystem functions.
Characteristic soils and soil quality monitoring practice
The soils of Crete reveal various stages of soil development. Cambisols are widely present on the island covering 43% of the total area. Leptosols are located mainly in mountainous areas covering 50.9%. Fluvisols and Luvisols are mainly located in the river floodplain areas and cover a small percentage. Soils have been formed in a variety of parent materials such as limestone, shale, marl, conglomerates, flysch, and alluvial deposits. The dominant parent material is limestone covering 48.0% of the total area, followed by marl at 19.1%. Soil texture is mainly characterized as moderately fine, and evident in 78.0% of the total area. The next important class is medium covering 13.6% of the area. Fine textured soils cover only 6.9% of the area. As the Figure below shows, very shallow (depth 0-15 cm) and shallow soils (15-30 cm) are widely distributed throughout the island of Crete, covering 16.4% and 34.6% of the total area, respectively. Moderately shallow (30-60 cm) and moderately deep (60-100 cm) soils cover 14.1% of the area at 25.8% and 18.1%, respectively. Deep and very deep soils covers 8.4% of the island, and are characterized as the most productive soils. The high amount of rock fragment (RF) in the soils is an indicator of high degradation of the soils in the past. Soils with 40-60% RF in the soil surface covers 49% of the total area. The next important class of RF is 15-40% covering 29.3% of the total area. Concerning drainage, soils are characterized as very well or well drained (98%).
The existing practices can be characterized as positive or negative in terms of soil quality monitoring. The following practices are mainly evident in Crete: (a) intensive cultivation of land accompanied by disk harrowing and application of fertilizers and pesticides (negative), (b) integrated land management in olive groves by applying measures for environmental protection (positive), (c) drilling wells and expansion of irrigation in olive groves and vineyards (positive/negative), and (d) overgrazing in pasture land (negative). Intensive cultivation which is widely evident in the area has mainly negative impacts causing problems of soil erosion, ground water pollution, and deterioration of soil physical and chemical properties (decrease in soil organic matter content, soil aggregate stability deterioration).
Previous research and innovation actions on soil improvement and monitoring
The following research or actions on soil improvement and monitoring are or were going on in the island of Crete:
- Research on assessment of land management practices on soil erosion and land desertification (Agricultural University of Athens).
- Integrated land management practice in olive groves by allocating extra subsidies.
- Project on development of agricultural soil database and assessment of land suitability for crop production and vulnerability to land degradation (Greek Ministry of Rural Development and Food).
- Research on Desertification Mitigation and Remediation of Land: a global approach for local solutions – DESIRE (www.desire-project.eu).
- Research on Land Ecosystem Degradation and Desertification: assessing the fit of responses- LEDDRA EU project (http://leddra.aegean.gr/).
From the above studies and the studies carried out during the execution of iSQAPER project the following conclusions can be drawn affecting soil quality:
- The main soil treats on soil quality are soil erosion including water and tillage erosion, loss in organic matter content due to intensive cultivation or overgrazing the land, salinization of the low land due to over-exploitation of the water recourses, and land desertification under high degree of land degradation.
- Minimum tillage or no tillage in the olive groves and vineyards decrease soil disturbance, increase soil water conservation, improve soil aggregate stability, improve water infiltration into the soil, reduce water runoff and soil loss and decrease soil loss due to tillage erosion.
- Extensive sustainable grazing represents a management practice to protect grazing land from soil erosion by maintaining a moderate annual vegetation cover useful to reduce rain water runoff, and soil erosion. A vegetation cover of 40-50% constitutes a crucial value below it accelerated soil erosion occurs. In addition, soil compaction resulting from animal trampling has a secondary negative impact by degrading soil structure, reducing infiltration rate, and accelerating soil erosion.
- Olive plantations are the land use highly protecting the land from soil erosion and desertification. Olive trees can survive under adverse climatic conditions, protecting the soil from raindrop impact and soil erosion due to the presence of leaves during the whole year, increasing soil organic matter content and biodiversity under minimum or no tillage land management practice, and protecting the land from desertification.
The local stakeholders listed in Table 1 were involved throughout the duration of iSQAPER in a number of research tasks including: providing experimental sites for the soil quality assessment and agricultural management practice evaluation; testing and evaluating SQAPP; attending demonstration workshops; and providing venues for and hosting the field visits for an iSQAPER plenary meeting.
Table 1: Local stakeholders involved in the iSQAPER research programme
|Stakeholder type||Locations||Institution||Number and gender M/F||Role|
|Farmers, land managers||Chania, Crete||farm||1M||Land owner and land manager|
|Advisors||Chania, Crete||Agricultural extension service, private company||2M, 1F||Advisors to land managers/farmers, providing opportunities for agricultural products marketing, product certification, protection of environment|
|Policy-makers||Separate session on Program for Agricultural Development in Greece in which more than 50 people related to policy participated|
|Researchers||Chania, Crete||ELGO-DIMITRA Organization, Institute of Olive Groves, sub-Tropical Plants and Vines, Agricultural University of Athens||9M, 6F||Research, practical education for getting experience in the field of agriculture|
Soil quality assessment and agricultural management practice evaluation
Based on WOCAT database (www.wocat.net), iSQAPER selected 18 promising agricultural management practices (AMPs) with potential to improve soil quality (»Agricultural management practices in the iSQAPER study sites). Twelve examples of a number of these AMPs were identified in the Crete study site that conformed to the following criteria:
- the promising management practice has been implemented for at least 3 years;
- at least 2 different soil types are represented; and
- at least in 2 different first level Farming Systems (arable, permanent, grazing) are represented.
For each AMP plot, nearby control plots were also identified where the practice has not changed.
Table 2: AMPs identified in the Crete study site. Climatic region: Mediterranean temperate
|Plot number||Farming system||Farming system detail||Soil type||AMP general description||AMP number*|
|5.1||Permanent||Fruit trees and berry plantation||Calcisols||No-till||1|
|5.3||Pasture||Intensive||Cambisols||Change of land use practices / intensity level||18|
|5.4||Permanent||Fruit trees and berry plantation||Calcisols||Cross-slope measure||10|
|5.5||Arable||Permanently irrigated land - Flower, fruits and vegetables||Calcisols||Change of land use practices / intensity level||18|
|5.6||Arable||Permanently irrigated land - Flower, fruits and vegetables||Cambisols||Change of land use practices / intensity level||18|
|5.7||Pasture||Extensive||Regosols||Change of land use practices / intensity level||18|
|5.8||Permanent||Fruit trees and berry plantation||Leptosols||No-till||1|
|5.9||Permanent||Fruit trees and berry plantation||Regosols||No-till||1|
|5.10||Permanent||Fruit trees and berry plantation||Calcisols||No-till||1|
|5.11||Pasture||Intensive||Leptosols||Change of land use practices / intensity level||18|
|5.12||Pasture||Intensive||Cambisols||Change of land use practices / intensity level||18|
*Note: see »Assessing effect of management practices on soil quality - experimental framework for the full list and descriptions of the 18 promising agricultural management practices.
A first field campaign was conducted in 2016 to evaluate the soil quality in each of the paired AMP-control plots, using visual soil assessment methods (»Visual soil and plant quality assesment). The results from this and all the other study sites were combined to determine which AMPs can be shown to have a proven positive effect on soil quality, see »Assessing effect of management practices on soil quality - experimental results.
Those practices that are innovative for Greece were also described and added to the WOCAT database
- »Water and soil conservation by using rock fragments [Greece]
- »Soil erosion control by ridges [Greece]
- »Establishment of intensive grazing areas on low productive slopes [Greece]
The soil assessment campaign was repeated in 2018 on the two paired plots highlighted in green in Table 2 (5.9: No-till and 5.12: Change of grazing intensity level) with laboratory-based measurements added to the visual soil assessments. The aim was to investigate
- how measurements of soil quality parameters obtained from the visual assessments compared to those obtained from laboratory measurements;
- if different AMPs affected different soil quality parameters in different ways;
- and what impact the AMPs had on the principal soil threats.
For details of the assessment analysis methods and the results from this and all study sites see »Impact of promising agricultural management practices.
As a result of this extended analysis, the both AMPs exemplifying minimum and no tillage and change of grazing intensity level to a sustainable level were selected to demonstrate the positive impact management practice can have on soil quality (see »Demonstrations of recommended agricultural management practices in the study sites).
The AMP minimum and no tillage was implemented in olive orchards with the aim of reducing erosion and increasing organic matter content. Visual soil assessment shows that AMP has a profound effect on all soil structure indicators compared to the control, with the exception of topsoil compaction (where the results were equal). Measured soil properties show that soil organic carbon content under no-till was double that on the control plot. Modelling using PESERA suggests that no-till may reduce erosion to 54% of the amount in tilled plots.
The AMP extensive sustainable grazing also has the aim of reducing erosion and increasing organic matter content. Visual soil assessment shows a better structure, porosity, stability and degree of clod development for soils under the AMP and equal scores for the remaining indicators. Measured soi properties show an increase in soil organic carbon content and a reduction of erosion (modelled) to 36% of the level in intensively grazed plots.
SQAPP development, testing and evaluation
Of the 90 stakeholders who took part in the evaluation of the beta version of SQAPP, 12 were from the Crete study site. Participants were asked a series of questions relating to their expectations of SQAPP and the relevance of the soil parameters included in SQAPP, the assessment of soil threats and the suitability of the app's recommendations to their local context. The feedback and comments were combined with those from the other study sites and used in the further development of SQAPP. For details of the responses from all study sites see »Stakeholder feedback and SQAPP development.
On 4th July 2019 a demonstration event was organised in the ELGO-DIMITRA Organisation in Chania Crete to present the major findings of iSQAPER to stakeholders and to demonstrate minimum and non-tillage and extensive sustainable grazing as management practices of proven benefit to soil quality. The event was attended by around 18 participants. Members of the Crete study site team also attended a meeting of the Greek Ministry of Agricultural Development and Foods, Programme of Agricultural Development in Chania on 25 June 2019 again to present the research results about the AMPs. This event was attended by more than 50 people.
The results from this demonstration event and those held in the other study sites are summarised in »Demonstrations of recommended agricultural management practices in the study sites.
Leaflet describing the AMPs controlled grazing and no-till were prepared to accompany the demonstrations.
Taking account discussions with the stakeholders and feedback from the various research tasks and events in which they took part, it is anticipated that the iSQAPER research programme could have a lasting legacy in the Crete study site as indicated in Table 3.
Table 3: Activities in which iSQAPER's research programme could potentially have a lasting impact in the Crete study site
|Activity||Impact level: 0 - no impact, 1 - barely noticeable to 5 - important visible impact|
|Research results influencing farming practice||x|
|Uptake of recommended AMPs||x|
|Regular use of SQAPP||x|
|Development of new or enhancement of existing stakeholder networks||x|
|The involvement of new stakeholder types in existing networks||x|