Couvreur S.1, Defois J.1, Petit T.1 and Ben Arfa N.2
1Unité de Recherche sur les Systèmes d’Elevage (URSE), 2Laboratoire de Recherche en Economie et Sciences Sociales (LARESS), Univ Bretagne Loire, Ecole Supérieure d’Agricultures (ESA), 55 rue Rabelais, BP 30748, 49007 Angers Cedex, France; s.couvreur@groupe-esa.com
Abstract
The area and proportion of grasslands in the French agricultural area are decreasing, mainly in regions where cattle farming is dominant. Our aim was to study if local dynamics of grassland maintenance exist in those regions. Data taken from the two last agricultural censuses 2000 and 2010 at the smallest French administrative scale (‘canton’) were used. 977 cantons were selected to represent those intensive cattle farming regions. A spatio-temporal statistical analysis allowed us to identify 4 profiles of grassland maintenance dynamics: (1) an increase in area and proportion of grassland in a cluster composed by at least 5 cantons; (2) an increase or maintenance of area and proportion of grassland in one canton while a decrease in its neighborhood; (3) a decrease of grassland area but an increase of its proportion in the agricultural area in one canton, and a decrease in its neighbourhood; (4) a decrease in area and proportion of grassland in one canton but lower than its neighbourhood. Depending on location, the local dynamics of grassland identified were linked to complex combinations of factors (pedoclimatic conditions, stakeholders, urban areas…) where public policy appeared as a common explanatory factor for grassland maintenance in numerous areas.
Keywords: grassland maintenance, spatio-temporal dynamics, cattle farming
Introduction
Despite a decrease in French grassland areas between 1960 and 2005, research programs have shown that grasslands (natural/permanent/temporary), associated or not to other forage crops, can offer multifunctional services improving (1) economic (Garambois and Devienne, 2012), (2) environmental (Hopkins and Holdz, 2006), and social farming system sustainability (Huyghe et al., 2014). Based on these results, public policies as well as technical tools and advices have been developed since the end of the 90’s to promote the development/ maintenance of grasslands in cattle farming systems. Nevertheless, grassland areas still decreased during the last 10 years (-2%), mainly in the western regions where cattle farming is intensive and dominant. This decrease is described in the literature at a large scale (regional).
As there is a high diversity of crop systems at a local scale, our hypothesis was that despite a general decrease in cattle areas, local spatio-temporal dynamics of increase/maintenance of grasslands exists.
The objective of our study was to analyse the local spatio-temporal dynamics of grassland areas, between 2000 and 2010, in regions where cattle production is dominant and grassland areas is low in comparison to the French average.
Materials and methods
We used the two last French agricultural censuses dataset (2000 and 2010) at the ‘canton’ scale which is a local administrative unit (which represent 3,664 cantons in the metropolitan France). We considered that a ‘canton’ was a part of a cattle area if: (1) the proportion of the utilised agricultural area (UAA) dedicated to cattle was higher than the national average of 42% or (2) the share of cattle farms was higher than the national average of 34% or (3) the number of cattle was higher than the national average of 5,231 heads.
Then, we calculated the productive grassland (PG) area which is the sum of the temporary grassland area and the productive permanent grassland. In the selected ‘cattle cantons’, we considered a ‘canton’ with
little grassland areas if it had a proportion of PG in the UAA lower than the average of 50.56%. This made it possible to eliminate mountain regions where permanent grasslands predominate and cattle farming system is mainly extensive. We selected 977 ‘cantons’. Several cantons were isolated and others constitute continued areas in the North-West (NW1 and NW2), North (N) and East parts of France.
We focused our work in the NW1, NW2 and N continued areas to detect the spatial structure and dynamics of grassland location. Proportion of PG and rates of evolution between 2000 and 2010 of PG area and proportion of PG were used as input data. In order to gain insight into how grassland proportion changes across region, the local spatial autocorrelation using local indicators of spatial association (LISA indicator, the local Moran’s statistics) was calculated (Anselin 1995). Those statistics provide a measure, for each spatial unit (canton) in the region, of the unit’s tendency to have a value (of grassland area or proportion) that is correlated with values in nearby areas (similar or dissimilar values) (Anselin 1995).
The objective was to determine some cantons where grassland is maintained or developed between 2000 and 2010 and where dynamics are either similar between neighbours (clusters) or different from the neighbourhood (outliers). The high-high (HH) and low-low (LL) locations were referred to as spatial clusters, while the high-low (HL) and low-high (LH) locations were termed spatial outliers.
Finally, to understand the global dynamic of a geographical area, we surveyed stakeholders (advisors, experts, facilitators) and farmers in 7 clusters characterized by a positive PG evolution. Interviews were conducted according to 5 factors supposed to influence PG evolution: pedo-climatical conditions, socio-professional context, environmental issues, local policies, and economical context. We aimed to classify the factors for each cluster to identify the one appearing the most important in spatio-temporal PG positive evolution.
Results and discussion
We observed HH, LL, LH and HL dynamics in the studied regions. LL clusters and LH outliers were more important and extended (Figure 1). This result showed that a lot of ‘cantons’ lost grassland area, confirming an erosion of grassland areas at a regional scale between 2000 and 2010. This decrease is related to specialization and intensification of milk production, due to increases in maize crop areas at the expense of PG (Peyraud et al., 2009). In England, grasslands has increased in cattle areas in relation to the development of beef cattle farming and/or optimal pedo-climatical conditions for grassland production (Fowell, 2010).
Local dynamics of grassland maintenance exist. Continuous HH clusters were found in the three studied regions. The HL outliers were mainly located in the NW1 and NW2 regions. Even if the method used does not give explaining factors for grassland evolution, it gives original results that show how it could be interesting to associate spatio-temporal statistical analysis at lower scales to go beyond results and interpretations from larger scales. We observed 4 profiles of grassland spatio-temporal dynamics (HH clusters and HL outliers): (1) an increase in PG area and proportion of PG in the ‘canton’ and its neighbourhood; (2) an increase or maintenance in PG area and proportion of PG in the ‘canton’ while a decrease for these two variables in its neighbourhood; (3) a decrease in the PG area but an increase in the proportion of PG in the ‘canton’, and a decrease for these two variables in its neighbourhood; (4) a decrease in PG and proportion of PG in the ‘canton’ but lower than its neighbourhood.
PG could be locally maintained in cattle breeding areas despite a general trend of specialization, intensification, and herd enlargement which mainly lead to an increase of maize as principal forage for cattle diet. Our surveys showed that grasslands are conserved due to a complex combination of factors (pedo-climatic conditions, stakeholders, urban areas…) even if the public policy appeared as a common reason for grassland maintenance in numerous areas. In wetlands, environmental policy tools take part in grassland maintenance by supporting land use and landscape preservation. Those measures illustrate
that society recognizes the role of wet grasslands in the preservation of biodiversity and landscapes, and therefore the multi-functionality of agriculture. In this case, public policies are the pillar of grassland maintenance which constitute a worrying situation in case of its suppression. In other areas, maintenance of grassland results from the complex combination of several dynamics (farmers looking for ways to reduce feeding costs, innovative management of grassland, alternative forms of advice, increasing interaction between farms and cities leading to new ways of production,…). The hypothesis is that grassland crystallizes several issues and stakeholder’s strategies for land use which finally contribute to its maintenance. Grassland maintenance results from the balance between actions of the different stakeholders of territories: farmers, policy makers, civil society (Gibon, 2005).
References
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Gibon A. (2005) Managing grassland for production, the environment and the landscape. Challenges at the farm and the landscape level. Livestock Production Science 96, 11-31.
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Figure 1. Spatio-temporal dynamics of the proportion of productive grassland areas, between 2000 and 2010, in regions where cattle production is dominant and grassland areas are low in comparison to the French average. (N: North region; NW1: NorthWest region in Brittany and north part of Pays de Loire Regions; NW2: South part of Pays de Loire, North of Poitou and West of Centre Regions; A, B, C, D ... Examples of cantons within a region with a positive spatial grassland dynamic).