题干

在江苏某地进行稻田养鱼的实验研究.6月5日在一定面积的实验小区插秧后放养300条小鲫鱼(杂食性),稻田水深8~10cm.对照小区不放鱼,其他条件相同.所有处理设置3次重复,实验持续2个月,期间检测浮游植物生物量(干重).请回答下列问题:

(1)每个处理设置3次重复,其主要目的是____ 

(2)实验的第一个月期间,检测发现实验组浮游植物生物量显著高于对照组,原因分析如下:放鱼对浮游植物的不利之处是鱼的取食作用;有利之处是鱼粪便为浮游植物提供营养物质,以及鱼会大量捕食____ 从而减弱其对浮游植物的捕食作用.在此期间,有利因素占据优势.

(3)实验的第二个月期间,所有小区的浮游植物生物量均显著下降,主要原因是此时生长旺盛的水稻与浮游植物之间具有____ 关系.

(4)放养鱼增加了该生态系统中____ 的复杂性,从而增加了该生态系统中____ 的速率.

(5)除了上述因素之外,对该实验研究影响最大的不定因素是____  (填序号).

①鸟       ②土壤质地   ③光照     ④水体肥力    ⑤稻田杂草.

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    Life can be so wonderful, full of adventure and joy. It can also be full of challenges, setbacks and heartbreaks. Whatever our circumstances, we generally still have dreams, hopes and desires—that little something more we want for ourselves and our loved ones. Yet knowing we can have more can also create a problem, because when we go to change the way we do things, up come the old patterns and pitfalls  that stopped us from seeking what we wanted in the first place.

    This tension between what we feel we can have and "what were seemingly able to have is the niggling  suffering, the anxiety we feel. This is where we usually think it's easier to just give up. But we're never meant to let go of the part of us that knows we can have more. The intelligence behind that knowing is us—the real us. It's the part that believes in life and its possibilities. If you drop that, you begin to feel a little "dead" inside because you're dropping "you".

    So, if we have this capability but somehow life seems to keep us stuck, how do we break these patterns?

    Decide on a new course and make one decision at a time. This is good advice for a new adventure or just getting through today's challenges.

While, deep down, we know we can do it, our mind—or the minds of those close to us—usually says we can't.

    That isn't a reason to stop, it's just the mind, that little man or woman on your shoulder, trying to talk you out of something again. It has done it many times before. It's all about starting simple and doing it now.

    Decide and act before overthinking. When you do this you may feel a little, or large, release from the jail of your mind and you'll be on your way.