On the one hand, are crop communities that, notwithstanding the use of mixtures, alley cropping and other mixed approaches in horticulture, are essentially high density – low diversity and genetically controlled by man's direct intervention.
In this publication, we presented a model of CAS that we found efficient, which we are promoting for other crop communities as a generic model applicable to other plant genomes.
Later, Donald took the idea of group versus individual performance farther and referred to 'communal plants': 'A "communal plant" has features in accord with the success of the crop community rather than the plant itself' (Donald 1981).
The best-known tradeoff between individual-plant competitiveness and crop-community performance is that linked to stem height.
Natural selection will usually favor competitiveness in such cases, but plant breeders can reverse the effects of past natural selection and select for better crop-community performance.
Given the dominance of short-range dispersal in earthworms, the rapid change in earthworm densities following conversion, suggests that population increases are driven primarily by the recruitment of new progeny from the standing arable crop community.
Stomatal opening is not the only basis for such tradeoffs; natural selection can lead to wasteful over-investment in roots in dry environments, with each plant essentially stealing soil water from beneath its neighbors, with no overall benefit to the crop community (Zhang et al. 1999).
For a warning we can look to the devastation brought by the same herbicide tolerant crops on communities in the US and Argentina.
It's vital that the people we live among are getting clean water, that farmers are able to grow their crops, that communities aren't buried under trash.
Because agriculture relies on the mass cultivation of a handful of starchy crops, a community's whole livelihood can be wiped out overnight by bad weather or pests.
Here we describe the dynamics of non-crop plant communities over an annual cycle in a semiarid Mediterranean agro-ecosystem, and discuss the potential linkages and implications for rabbit damage management.
