What went right in I. Mongolia and what went wrong in Tibet

A news focus article "Getting at the Roots of Killer Dust Storms" on this week's [*Science*](http://www.sciencemag.org/cgi/content/full/317/5836/314?etoc) reported the recent progress in combating desertification by grazing management and ecological restoration in Bayinhushu, Inner Mongolia.

Apparently by reducing the number of livestocks and grazing intensity, as well as natural restoration, after five years the vegetation in this villiage is recovering towards the level 50 years ago. The production of pastoralism products are not hindered as the output per livestock doubled due to improved nutrient from corn planted by villagers instead of natural grown grass.

Other measures employed before, such as forestation and settlement development, proved not feasible while counterproductive in the semi-arid areas. Trees either die or suck too much groundwater, thus make draught worse. Settled communities brings higher pressure to the land and create denuded rings around their villages.

The success in Inner Mongolia is due to its consideration over economic and social as well as ecological effects. Such approach suits better to the local situation. However, the successful method cannot simply be copied to other semi-arid areas in China, such as Tibet Autonomous Region (TAR). Inner Mongolia has better water and nutrient conditions than TAR. If it is to be imitated, at least local environmental conditions should be considered first.

In some areas in Tibet, where moving sand dunes make the hand-off approach not feasible, human intervention may be needed to stablise sand dunes first, then surface vegetation can be reestablished. The fragile economy and poor soil in Tibet may prove difficulties to local people who are asked to control the grazing. But the experience from Inner Mongolia does provide a more desirable to restore grassland in Tibet than the current settle-down policy.

ifmslide -- 一个似乎没什么人用的 LaTeX 演示宏包

今天在无聊的时候随便用 locate 命令看了一下自己的硬盘，发现 TeXlive 2005 里还有一个用于制作 slide 的宏包，叫做 ifmslide。这个东东似乎利用了 texpower、seminar 等多个宏包的功能，有一些它自己的特点，包括：

- 可以方便地定义背景图像；
- 可以自定义导航按钮的形状和位置；
- 可以方便地开关导航栏和定义导航栏位置；
- 用 pdf 格式时生成幻灯片，用 dvi 格式可以生成 handout ，基本不需要改动代码。

不过还不清楚对中文支持如何，也不清楚是否像 Beamer 那样支持 pgf 提供的绘图命令。另外一个缺点就是没有提供设计好的模板，不清楚做出来的幻灯片美观程度如何。