At an altitude of 5.5 Kms above sea level the air pressure, and the amount of oxygen in every lungful of air you take in, is a little less than half of what you have at sea level. The amount of water available also decreases as you go up. The thin air and lack of water make for high deserts. Until you get to the edge of the snow line. Here, where melt water is abundant in summer, life thrives. As we approached the high pass of Khardung La in Ladakh we entered such an altitudinal oasis.
Vegetation was sparse right at the top. But just a little way down was the village of Khardung, sitting on a stream that flowed from the meltwater around the pass. But even before we reached the village, we could see meadows where cattle were at a leisurely breakfast. I looked carefully at the black shapes: all were cows or dzos, crosses between cows and yak. But not a single one had the muscular shoulders of the yak.
Sitting quite apart from the cattle were a few donkeys. This was the first pack animal I’d seen in Ladakh. In many parts of the Himalayas and trans-Himalayas, motorized vehicles have replaced the mules and donkeys which were common a lifetime ago. But perhaps in these remote villages, where life can be snowbound for half the year, donkeys are still useful.
Right at the top of the pass I’d seen flocks of yellow-billed chough (Pyrrhocorax graculus, also called Alpine chough) do the aerial acrobatics they are so fond of. The air was full of their deep musical tones. I looked carefully but saw none of their red-billed cousins. Both are creatures of heights; you won’t see them in Leh. On the chorten where the chough sits (in the featured photo) I could see sprigs of juniper. There were no trees that I could see. Do people bring juniper branches with them when they cross? Lower down, just above the 4.8 Kms mark, we stopped for a chai. Flocks of pigeons wheeled in the air. Most were common pigeons (Columba livia), but I saw a few Hill pigeons (Columba rupestris). The one in the photo above was a lifer; the white band on the tail, and the white under the wing are characteristic of this species. Later I saw many more in Leh.
While we had chai there was time to look at the vegetation in this altitudinal oasis. There were stunted bushes of something that could be a tulsi or mint. The nearest bushes lay up-slope, and I wasn’t up to a climb to examine them closely. So I had to pass up the chance at a better identification and satisfied myself with the possibility that this belonged to family Lamiaceae. Of course, this is a large family, with over seven thousand species, but there cannot be many that grow so high up.
I’d been seeing bright orange patches on stone as we came down from the pass. They were to bright to be the mineral colours that we’d seen in rocks in this low-oxygen environment. Now that I could take a closer look, I found that it was the common orange lichen (Xanthoria parietina). This is a leafy lichen, a hybrid of fungi and algae. I find the symbiosis of different organisms making up lichens to be very interesting. For the first time on this trip I missed by dedicated camera for macros.
I’d put down the green cover for grass, but just before getting back into the car, I took a photo of some of the spreading cover nearby. I was not correct. There was grass, of course, but quite a bit of the green was due to a spreading succulent. I should have thought of it, deserts are usually full of succulents. It’s one way plants have of conserving water in a dry environment. Now that I know there’s such a variety of life at this altitude, I’ll have to stop and look carefully in future: perhaps I’ll even get to see the insects and small mammals which live up here.