Regarding impacts on SJV, HSR would benefit and promote population, not agriculture. As a matter of public policy, why on earth would we want to promote population growth in the SJV? It's a terrible place to live, the only advantage (assuming you don't need to be there for other reasons) is cheaper land. But the costs in healthcare due to air pollution and in energy consumption due to high demand for residential air conditioning would be considerable. And the energy savings in replacing air travel with rail would be offset by the creation of new travel demand between the SJV and SF/LA. It's all for the developers, I suspect.