Vở Bài Tập Sinh Học Lớp 9 (Tập 2) EPub tải xuống miễn phí

Biro Timea _imita — Astronauts go to Mars and discover a crashed spaceship. They find interesting things there. I didn't really like the book as it introduced a very interesting idea, but then didn't explore it very well. Cool idea but underexpoited.

Ollie Brant obrant805051b — very well written. It's such a nice book and I loved the way author explained her whole life and just everything about the main character's memories were very happy. However, the character is in a coma and her brother and her parents died, making this book not from being overly happy and boring but helps make it suspenseful especially when you wait to see if she's going to wake up from the coma. I swear, near the end I was going to cry. not really but still

Helena Cordeiro mhsc — If I had to put it into one sentence I would have say that: deforestation is the #1 cause of collapse and should be avoided like the plague. Diamond proposes 5 main factors for collapse of a given human culture (not gradual decline but abrupt events) Factors appear in no particular order. 1) level of inherent environmental fragility (as opposed to environmental resilience) 2) friendly trade partners 3) hostile relationships with neighboring civilizations 4) climate changes (Diamond does not address cause except for 1)anthropogenic and local) (3 others: natural and global, natural and local or Anthropogenic and global) 5) cultural inflexibility with regard to predispositions that affect survivability The book chooses as illustrations of the 5 factors at work both ancient and recent cultures as well as current non-collapsed cultures. The message is one of hope and information/education that we might avert tragedy and make better choices for the future for ourselves. As the book progresses from ancient to current Diamond lists some 12-13 environmental problems in a succint and informative manner...stuff like: disasters of rampantly dominating "introduced exoctic" plants and animals, salinization of soils, loss of topsoil through wind or water effects, erosion causing eutrophication of lakes and rivers, loss of plant and animal diversity, deforestation, toxic waste from mining or industrial activity, loss of estuarine habitat from water diversion, loss of wetlands from human road and building, etc As an example of #1 above using loss of topsoil - the first Viking colonists in Iceland had no idea that the soils of Iceland were brought by the wind and could be taken away again by the wind. They were used to the heavy soils of Norway and Ireland. Wind erosion of soil was only understood after significant land areas were devoid of soils and became useless barren wastelands. Lucky for the Icelanders it was percieved and their behavior was modified to prevent wind erosion such that some forms of agriculture can exist profitably today on those lands which were not farmed in ancient times. Diamond is very compassionate and does not postulate that people were stupid or willfully wasteful, rather the opposite is true, he points out that people were acting as best they could under the circumstances and simply did not have the tools or knowledge to do otherwise in most cases. Modern case studies include interviews with people who lived through some relatively less complete collapses. Diamond also cautions us about the hows and ways of inaction in the face of peril that we are now seeing in our current situation worldwide and in the not so distant past. The most bizarre case of #5 was the Norse colony on Greenland from circa 984 to 1425 in which they all starved to death, some 5000 inhabitants completely gone. From the archaelogical record which is clear from other sites that the Inuit ate fish yet the Greenlanders did not eat the abundant fish which were present in the streams and the ocean nor did they learn from the Inuit or befriend them to achieve mutual benefit. They did eat the seals but only the ones they could club on the shore. This is particularly strange as the colonists were originally from Norway and those middens from the medieval time period show ~50% of diet of Norwegians to be fish. Climate change does enter into the equation because it was the colder conditions which pushed the Greenlanders over the edge as much as anything else. They might have lasted a little more than 400 years and had better lives if they had eaten fish but the "Little Ice Age" of Europe which began in the early 1400s was pretty much going to get them sooner or later, as it did to the Inuit who lasted 700 years in Greenland.

Mennatallah Elwan _ika — This is a very important book to read and understand if you are in a domain that needs to forecast.

Ms Jahb jonesmess — Much harder to read the true story...