  In this Letter we study the connection between the large-scale dynamics of
the turbulence cascade and particle heating on kinetic scales. We find that the
inertial range turbulence amplitude ($\delta B_i$; measured in the range of
0.01-0.1 Hz) is a simple and effective proxy to identify the onset of
significant ion heating and when it is combined with $\beta_{||p}$, it
characterizes the energy partitioning between protons and electrons
($T_p/T_e$), proton temperature anisotropy ($T_{\perp}/T_{||}$) and scalar
proton temperature ($T_p$) in a way that is consistent with previous
predictions. For a fixed $\delta B_i$, the ratio of linear to nonlinear
timescales is strongly correlated with the scalar proton temperature in
agreement with Matthaeus et al., though for solar wind intervals with
$\beta_{||p}>1$ some discrepancies are found. For a fixed $\beta_{||p}$, an
increase of the turbulence amplitude leads to higher $T_p/T_e$ ratios, which is
consistent with the models of Chandran et al. and Wu et al. We discuss the
implications of these findings for our understanding of plasma turbulence.
