Great read. Thanks.
Oh wow that's remarkable!
Have you "liked" a post today?
Woah! These are great
Just a thing on Tectonic Plates. In large Oceanic plates you can get these things called 'hot spots' which are beleived to be where the plate begins to weaken in the middle and causes magma to rise up and cool causing small island in the middle of the ocean. This may be a very good tool for some stories. Massive ocean seperating 2 continents seemingly untravelable due to distance, but a small island make it just about do able? An island in the middle of the sea with some powerful magician living in iscolation?
I'm new and have no experience with finishing a world but if you make a list of things you want to cover, I and others may be able to help?
Great posts, I agonize about the same things. I would like to add Trade, Transport and Sanitation. One of the most under appreciated aspects of the world is moving water. Water in, **** out. A river provides all of these things. Irrigates crops, provides fish, brings boats (an efficient form of transport in a pre-industrial world) and carries away waste. Cities grew up around markets... weekly, monthly, yearly. A good market and people stayed, as long as there was a market. 2 pence? Is that the same 2 cents worth?
Apologies, I missed several pages of posts before I opened my mouth. I see three great threads (courses) here: Planets, Geology and migration; Empires, Kingdoms, Politics and Collapse; Cities and Population Growth... I love all three, are there separate forums (classrooms)?
Thanks KartoKilt (and everybody else who has commented here). I really should make some more posts to this thread since it seems pretty popular. I'm planning a lengthy series on the form/history/growth of cities, but I don't see it happening in the next few months. Sorry to those people following this thread, and be aware, I haven't forgotten about it.
THW
Formerly TheHoarseWhisperer
If I may expand DEMurray's comment on trees a bit...
After reading a fair number of academic guesstimates, I've developed a short set of 'rules of thumb' for forests coverage.
Rule 1. If there were no people, forest coverage is immense. Trees tend to win over grass if the climate supports both.
Rule 2. For civilized but not industrial civilization there's a simple relationship between deforestation and population density, excluding the bottom 15% extremes. At 50 people per square km mi, forests are reduced by 50%. At around 85 pop/kmmi^2 forest coverage has been reduced to ~15%. At this point a severe change in slope happens, and the curve runs from here through ~12% coverage for 160 pop/kmmi^2 to the extreme point of ~7% for 200 pop/kmmi^2.
I want to accent that very last point. For pre-industrial age (ie before about 1800 in US and western Europe) it sort of looks like there's a cap on population density of 200 people per square kilometer mile. It's basically a Malthusian breakpoint. Even with that there's about 7% of forested land that's just too inaccessible for use, too marginal for farming, or whatever, and it remains untouched or replanted.
It looks like a depopulation event causes reforestation. From what we can tell, the depopulation of the world in the mid to late 14th century was accompanied by an increase in forest coverage. Sure it was "new growth" forest, but it was reforestation nonetheless.
The above is a general guidance. As an example that emphasizes DEMurray's point, Scotland pretty much deforested itself despite remaining under 60 pop/kmmi^2, and despite heavy use of peat for heat. My theory is that it was because so much of the land was marginal for farming; that it took more acreage to feed a population and so more land needed cleared, but I'm just guessing from available estimates.
Post-industrial, by the way, appears to maintain a pretty constant 6 to 9% forestation rate regardless of average density. Food production gets more efficient per acre, and population growth increases local densities instead of spreading.
edited to correct units of measure. deleted km and replaced with mi.
Last edited by kirkspencer; 03-13-2014 at 02:45 PM. Reason: mind catching up with fingers and making corrections.
HW,
I just registered the other day and am officially in love with these posts!
Thanks Dave.
Formerly TheHoarseWhisperer
@kirkspencer Using the data you so generously gathered, as well as some gratuitous rounding to make my math easier on me, I created an equation to find the (approximate) forest reduction as a percentage, given the population density and vice versa.So, if you have the population density (in people per square mile), to find the approximate forest reduction (as a percentage of original forest), multiply the PD by 0.45 and add 17. To go in reverse (FR to PD), subtract 17 and divide by 0.45. I'm not sure why you would have the FR and not the PD, but it might be useful somehow.y=0.45x+17
Method Comparison:
FR (%) over PD.png
The blue line is your data, and the red line is mine. The yellow line is something of a combination of the two where the slope is 0.535 and the y-intercept is 0, so that it meets both the first and last of your data points, but still remains linear, like mine. Obviously, mine is less accurate than yours, but it does allow for a (kind of) easy method to calculate forest reduction (or population density, if need be).