4 nature shots from a newbie... C+C please

[Fotografer]

1)<img src="http://farm3.static.flickr.com/2451/3771068738_7946b1c2e4_o.jpg" border="0" alt="" /></p>
<p>aperture:f/5</p>
<p>shutter speed:1/640</p>
<p>iso100</p>
<p>&nbsp;</p>
<p>2)<img src="http://farm4.static.flickr.com/3516/3771068672_bbc3e6cf40_o.jpg" border="0" alt="" /></p>
<p>aperture:f/3.5</p>
<p>shutter speed:1/1000</p>
<p>iso100</p>
<p>&nbsp;</p>
<p>3)<img src="http://farm3.static.flickr.com/2508/3771068530_df6b29afaf_o.jpg" border="0" alt="" /></p>
<p>aperture:f/5.6</p>
<p>shutter speed:1/60</p>
<p>iso160</p>
<p>&nbsp;</p>
<p>4)<img src="http://farm4.static.flickr.com/3600/3770269023_ed66d888d9_o.jpg" border="0" alt="" /></p>
<p>aperture:f/8</p>
<p>shutter speed:1/125</p>
<p>iso100</p>
<p>&nbsp;</p>
<p>all of these pictures were taken on a canon T1i with the 18-55mm kit lens. all of these were shot in the auto mode specifically on landscape or close-up mode, i cant remember. anyways let me know how i could have shot these better</p>
<p>&n