[求助] HELP ME!!! 救救我的凤梨！！！

聪聪

[em44]

不知怎么了，家里的那颗凤梨叶子顶端开始变黄，发脆，大约有一个礼拜了。
这是什么原因造成的？我该怎么办呢？大家帮帮我呀！多谢了！
<img src="attachments/dvbbs/20042261056683871.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/20042261056683871.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />

聪聪

有一片叶子中间部分也发黄了
<img src="attachments/dvbbs/20042261141933348.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/20042261141933348.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />

聪聪

我看书上说，适合凤梨的土壤ph值在4-5，怎么那么酸的土壤啊？

平时这颗凤梨是放在屋里的，今天拍照才拿到阳台上的