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This paper presents an alternative approach for high spatial resolution vegetation productivity mapping at a regional scale, using a combination of Normalised Difference Vegetation Index (NDVI) imagery and widely distributed ground-based Above-ground Net Primary Production (ANPP) estimates. Our method searches through all available single-date NDVI imagery to identify the images which give the best NDVI–ANPP relationship. The derived relationships are then used to predict ANPP values outside of field survey plots. This approach enables the use of the high spatial resolution (30 m) Landsat 8 sensor, despite its low revisit frequency that is further reduced by cloud cover. This is one of few studies to investigate the NDVI–ANPP relationship across a wide range of temperate habitats and strong relationships were observed (R2 = 0.706), which increased when only grasslands were considered (R2 = 0.833). The strongest NDVI–ANPP relationships occurred during the spring “green-up” period. A reserved subset of 20% of ground-based ANPP estimates was used for validation and results showed that our method was able to estimate ANPP with a RMSE of 15–21%. This work is important because we demonstrate a general methodological framework for mapping of ANPP from local to regional scales, with the potential to be applied to any temperate ecosystems with a pronounced green up period. Our approach allows spatial extrapolation outside of field survey plots to produce a continuous surface product, useful for capturing spatial patterns and representing small-scale heterogeneity, and well-suited for modelling applications. The data requirements for implementing this approach are also discussed.

This report was presented at the UK Organic Research 2002 Conference. This paper describes the approaches and preliminary results of a study that is designed to provide a large amount of data at a range of scales in order to investigate the potential factors influencing biodiversity on arable farmland on comparable organic and conventional farms. In particular, the study examines the role of non-crop habitats within the different farming systems and how the extent and management of non-crop habitats differs between them. A detailed description of the methodologies being employed to establish differences in non-crop habitat, plant, invertebrate and bird diversity is given. The study remains in its early stages as a result of the impact of Foot and Mouth disease on the fieldwork schedule during 2001. The process of setting up the study revealed that the numbers of farmers growing cereals organically are low as a proportion of the organic sector as a whole, despite recent large increases in numbers of farmers converting to organic production. Preliminary results from the first year of fieldwork on plants reveal significant differences between organic and conventional farms in terms of the numbers of weed species on fields and non-significant differences in numbers of species found on non-crop habitats.