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This category has the following 16 subcategories, out of 16 total.
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499:
Renewable resource companies established in the 1920s
482:
Renewable resource companies established in the 1910s
15:
83:
535:
458:Protected areas established in the 1920s
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549:20th century in the environment
63:human impact on the environment
1:
46:These articles relate to the
519:1920s individual tree deaths
7:
10:
570:
434:1920s natural disasters
386:1929 in the environment
369:1928 in the environment
352:1927 in the environment
335:1926 in the environment
318:1925 in the environment
301:1924 in the environment
284:1923 in the environment
267:1922 in the environment
250:1921 in the environment
233:1920 in the environment
544:Environment by decade
79:environmental issues
49:natural environment
26:Environment portal
410:1920s meteorology
67:environmental law
61:They include the
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75:environmentalism
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71:conservation
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40:1920s portal
462:(11 C, 1 P)
438:(18 C, 1 P)
54:the decade
538:Categories
390:(7 C, 2 P)
373:(6 C, 3 P)
356:(7 C, 4 P)
339:(5 C, 3 P)
322:(5 C, 1 P)
305:(5 C, 3 P)
288:(6 C, 3 P)
271:(5 C, 2 P)
237:(8 C, 2 P)
414:(13 C)
554:1920s
523:(2 P)
503:(5 C)
486:(4 C)
254:(5 C)
139:1970s
134:1960s
129:1950s
124:1940s
119:1930s
114:1920s
109:1910s
104:1900s
99:1890s
94:1880s
89:1870s
56:1920s
202:25th
197:24th
192:23rd
187:22nd
182:21st
176:20th
170:19th
165:18th
160:17th
155:16th
150:15th
77:and
222:0–9
52:in
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81:.
73:,
69:,
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512:T
471:R
447:P
423:N
399:M
59:.
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