Before listing the main causes and consequences of this mounting threat, people should know that, according to the UN, desertification does not refer to the expansion of deserts, but rather the degradation of land in arid, semiarid and dry subhumid
areas, primarily as a result of human activities and climatic variations.
Its climate is temperate subhumid
, with an annual rainfall of 950 mm and temperatures between 6 and 25 C.
Burrows G E (2001) Comparative anatomy of the photosynthetic organs of 39 xeromorphic species from subhumid
New South Wales, Australia.
Sustainability of crop yields in dry subhumid
zones of marginal agricultural productivity requires integrated modelling approaches to provide the necessary feedback for adapting agrohydrological functions to changing seasonal soil moisture regimes .
For example, "savannah climate" under the Kooppen designation corresponds to what Garcia  terms as "warm, subhumid
climate with summer rains." However, in Mexico, the thermal and humidity conditions that are associated with this classification are characteristic of high or low seasonal rain forests rather than savannah.
The limit between the subhumid
and semiarid zones is represented by the 500 mm isohyet.
While formation of pedogenic carbonates is most common in arid to subhumid
environments (<750 mm [yr.sup.-1]; ), under strongly seasonal climatic regimes, pedogenic carbonate may form under much wetter conditions in a mean annual sense.
Impact of three and seven years of no-tillage on the soil water storage, in the plant root zone, under a dry subhumid
The altitude is 990 m asl, and the climate is warm subhumid
. Annual average temperature is 23.5 [degrees]C; annual rainfall is 840 mm, and the rainy season is from Jun to Oct (INEGI 2010).