For one thing, aeroponics uses specific equipment that has a high start up cost.

首先，无土栽培需要使用价格昂贵的特殊设备。

Aeroponic systems may require artificial light so energy costs can be higher and the system is pretty sensitive.

无土栽培系统需要人造光，因此能源成本高，且这种系统很敏感。

And we also have some backup farming with aeroponics and hydroponics.

我们还有一些气培法和水培法的备用农业。

So this is an aeroponic garden, so you can see some baby bok choy, you can see some like butter greens.

这是一个空气栽培花园，你可以看到一些小白菜，黄油绿叶菜。

Aeroponic farming, he says, is 'virtuous'.

他说，气培农业是“良性的”。

Aeroponic farms use a tiny fraction of the water that is used in in-ground farms. And they can grow food much faster, about 40 percent faster.

气培农场使用的水只是地下农场用水的一小部分。他们可以更快地种植食物，大约快 40%。

So imagine almost like a vertical section through this landscape that goes from the air above, where we have vertical farms;below, we have the aeroponics and the aquaponics.

因此，想象一下从上方的空气中穿过这片景观的垂直剖面，我们在那里有垂直农场；在下方，我们有气培法和鱼菜共生法。

Pascal Hardy, an engineer and sustainable development consultant, began experimenting with vertical farming and aeroponic growing towers – as the soil-free plastic tubes are known – on his Paris apartment block roof five years ago.

工程师兼可持续发展顾问帕斯卡·哈迪（Pascal Hardy）五年前开始在他的巴黎公寓楼屋顶上试验垂直农业和气培种植塔（即无土塑料管）。

Now most of these farms are hydroponic or aeroponic systems, which means that instead of using soil, they use a substitute material like polyurethane sponges, biodegradable peat moss and even use inorganic materials like perlite and clay pellets.

现在这些农场大多是水培或气培系统，这意味着他们不使用土壤，而是使用聚氨酯海绵、可生物降解的泥炭藓等替代材料，甚至使用珍珠岩和粘土颗粒等无机材料。