Tuesday, 2 November 2010

Climate Change and Agro-Ecosystems

The potential impacts of the changing climate (and I am going with the broad consensus that the global climate is undergoing relatively rapid change) on agro-ecosystems are diverse and includes a possible asynchrony between organisms that have, for example, evolved either mutually beneficial relationships (e.g. bees and flowering plants) or predator-prey relationships.

In general, spring is advancing [remember: climate not weather, trends not point data] leading to earlier flowering and emergence of insects (among other things).

Theoretically, this could cause significant problems if (for example):

  1. Early flowering crops (e.g. apple) flower significantly in advance of their pollinators (honey bees) emergence and population build up. Alternatively if the pollinators emerge before there are any flowers they may starve and die. Both could lead to poor pollination and low yield.
  2. Pest and predator emergence is too far apart leading to increased pest populations and a requirement for increase pesticide treatments.
Interest in phenology has been increasing in the UK following the enormous success of the Springwatch project (and Autumn Watch etc) which grew from the efforts of Dr Tim Sparks (at the time a researcher at the Centre for Ecology and Hydrology in Cambridge) to recreate a Phenology Network in the UK. Tim is still closely involved in the Phenology Network and continues to research in this area.

It was a recent paper (Sparks et al, 2010) from Tim and his Polish colleagues that triggered this first post (others are likely to be similarly stumbled upon). They reported a trend over 25 years  (1985 - 2009) where the first cleansing flight of the Honey Bee (Apis mellifera) become earlier by 1 month and concluded that this was due to the increasing temperature during spring at the study sites in Poland. Some early flowering plant species nearby had also developed earlier by around 20 days over a 30 year period.

The authors suggest that "This earlier activity gives hope that the reported earlier flowering of many native and cultivated species will not cause a pollination synchrony crisis" but, quite correctly, stress the need for further research in this area.

Frankly, if some of the energy spent arguing about who is responsible for the current changing climate were redirected to increasing the research on what the longer term effects will be and how we should prepare for the challenges they will bring, I would be much happier!

Sparks, TH; Langowska, A; Glazaczow, A; Wilkaniec, Z; Bienkowska, M; Tryjanowski, P. 2010. Advances in the timing of spring cleaning by the honeybee Apis mellifera in Poland. Ecological Entomology, DOI: 10.1111/j.1365-2311.2010.01226.x