Evaluation of strip intercropping concept with grass-clover and maize strips to produce biomass for bioenergy

Summary

To enhance integrity of organic farming it is important not only to deliver high quality food products to a growing market but also to include strategies to reduce the reliance on fossil fuels and decrease total greenhouse gas emissions. In this context, the increased use of perennials within traditionally more annual-based rotations may gain significant importance. The objective of this study was to determine the effect of a strip cropping strategy combining intercropping of a grass-clover based perennial forage crop mixture (soil fertility building (SFB) crop) and maize in strips on the biomass productivity per land area and to determine interactions between strip border rows and associated mechanisms responsible for a potentially improved resource use compared to traditional sole cropping. Strip intercropping is defined as the production of two or more crops within the same field in strips wide enough that each can be managed independently by existing machinery; yet narrow enough that the strip components can interact. The combination of the already established grass-clover pasture and the maize sown medio May where the growth rates in grass-clover is relatively high in a strip cropping system is challenging primarily because the interspecific competitive ability of the perennials towards the annuals seems to be too dominating. Such early competitive advantages obviously lead to greater initial size and since growth tends to be self compounding as a result of size asymmetric competition resulting in less annual strip productivity throughout the cropping season. The present strip cropping system does not possess the right level of co-existence and complementarity qualities in order to strike the right balance in the complex agro-ecosystem to obtain maximum overall benefits. Maize is clearly a high yielding crop but also a crop requiring considerable N application rates before this can be obtained. When taking into account that N is frequently considered to be one of the key limiting factors responsible for the limited productivity of organic systems it might be questioned whether additional use of N to maize is a sustainable strategy for producing biomass to bioenergy in a future with potential limitations on import of conventional manure to organic cropping systems. On the other hand increasing amounts of N rich digestates might be available at maize have an efficient soil mineral N uptake throughout the whole growing season terminated mid October in the present study.

Available Versions of this Item

• Evaluation of strip intercropping concept with grass-clover and maize strips to produce biomass for bioenergy. (deposited 27 Jun 2011 15:04) [Currently Displayed]
  • Annual maize and perennial grass-clover strip cropping to produce biomass for bioenergy – within an organic farming approach. (deposited 13 Jun 2012 06:48)