Rising human population density, combined perhaps with a cooling, drying climate, left the Natufian hunter-gatherers of the region short of acorns, gazelles and wild grass seeds.

人口密度的上升，结合其他如气候变冷变旱的因素，使采猎为生的纳图夫人(Natufian—约公元前1万年的史前人)短缺橡果、羚羊和野草种。

youdao

Walnut tree is bigger, the planting density is low, such as alfalfa, ryegrass, dwarf crops, grass to care, to promote the production of fertilizer.

核桃树体较大，定植密度较低，如紫花苜蓿、黑麦草、矮秆农作物等，以草养地，以肥促产。

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Also timing dung, and another clear mat grass, reduce the breeding density appropriately.

还要定时清粪，另换垫草，适当减小饲养密度。

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Niman's cattle graze on high grass for at least 14 months and then spend 5 months at low-density (83 cattle per acre) feedlots.

FORBES: One Man's Meat