Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The CharXive Challenge. Regulation of global carbon cycles by vegetation
  fires   It is an open, but not unanswerable, question as to how much atmospheric CO2
is sequestered globally by vegetation fires. In this work I conceptualise the
question in terms of the general CharXive Challenge, discuss a mechanism by
which thermoconversion of biomass may regulate the global distribution of
carbon between reservoirs, show how suppression of vegetation fires by human
activities may increase the fraction of carbon in the atmospheric pool, and
pose three specific CharXive Challenges of crucial strategic significance to
our management of global carbon cycles.

22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom