huge file in pg_xlog and base

Hi,
I have 6 little dbs, but I see that my base directory needs 213MB and
log are 114MB.
Here my folder structure and size:

3571 ./base/1
3487 ./base/10792
4691 ./base/10793
3707 ./base/16384
16618 ./base/16386
0 ./base/64673/pgsql_tmp
143697 ./base/64673
0 ./base/86171/pgsql_tmp
6133 ./base/86171
5790 ./base/89667
6401 ./base/106022
7926 ./base/106521
11597 ./base/120343
213615 ./base
160 ./pg_subtrans
0 ./pg_twophase
8 ./pg_multixact/members
8 ./pg_multixact/offsets
16 ./pg_multixact
865 ./global
16 ./pg_clog
0 ./pg_xlog/archive_status
114800 ./pg_xlog
0 ./pg_tblspc
329484 .

Could you please suggest me how to reduce that space (if possible)?

Thank you,
Nico