  We show that the Longest Common Prefix Array of a text collection of total
size n on alphabet [1, {\sigma}] can be computed from the Burrows-Wheeler
transformed collection in O(n log {\sigma}) time using o(n log {\sigma}) bits
of working space on top of the input and output. Our result improves (on small
alphabets) and generalizes (to string collections) the previous solution from
Beller et al., which required O(n) bits of extra working space. We also show
how to merge the BWTs of two collections of total size n within the same time
and space bounds. The procedure at the core of our algorithms can be used to
enumerate suffix tree intervals in succinct space from the BWT, which is of
independent interest. An engineered implementation of our first algorithm on
DNA alphabet induces the LCP of a large (16 GiB) collection of short (100
bases) reads at a rate of 2.92 megabases per second using in total 1.5 Bytes
per base in RAM. Our second algorithm merges the BWTs of two short-reads
collections of 8 GiB each at a rate of 1.7 megabases per second and uses 0.625
Bytes per base in RAM. An extension of this algorithm that computes also the
LCP array of the merged collection processes the data at a rate of 1.48
megabases per second and uses 1.625 Bytes per base in RAM.
