Accelerated dryland expansion regulates future variability in dryland gross primary production

Primary Succession on a Hawaiian Dryland Chronosequence

We used measurements from airborne imaging spectroscopy and LiDAR to quantify the biophysical structure and composition of vegetation on a dryland substrate age gradient in Hawaii. Both vertical stature and species composition changed during primary succession, and reveal a progressive increase in vertical stature on younger substrates followed by a collapse on Pleistocene-aged flows. Tall-stat...

The potential role of sheep in dryland grain production systems

In dryland farming areas of Montana, annual precipitation is not sufficient for annual planting of cereal grains. Instead, a crop-summer fallow farming system is used to conserve soil moisture and increase available nitrogen for subsequent crop growth. Managing this summer fallow, either by mechanical means or with herbicides, is the highest variable cost associated with dryland grain productio...

Dryland Agriculture: Sociology

Carbon sequestration in dryland ecosystems.

Drylands occupy 6.15 billion hectares (Bha) or 47.2% of the world's land area. Of this, 3.5 to 4.0 Bha (57%-65%) are either desertified or prone to desertification. Despite the low soil organic carbon (SOC) concentration, total SOC pool of soils of the drylands is 241 Pg (1 Pg = petagram = 10(15)g = 1 billion metric ton) or 15.5% of the world's total of 1550 Pg to 1-meter depth. Desertification...

Dryland Rivers: Processes and Forms

Dryland alluvial rivers vary considerably in character. In terms of processes, high energy, sediment-laden flash floods in upland rivers contrast dramatically with the low sediment loads and languid flows of their lowland counterparts while from a form perspective, the unstable wide, shallow and sandy braid plains of piedmont rivers are quite different from the relatively stable, narrow, deep a...