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mostly suffered from strong disturbance including constant reclamation, repeated
abandon, and subsequent fallow-rotation practice. Furthermore, this zone is also
confronted with high soil erosion risk. Critically, farmers need to produce sufficient
food and clothing, and meanwhile get stable economic income resource from first
and second zones. In this case, farmers are required to first give up inefficient farm-
ing practice at the lands of the third zone, and correspondingly convert the lands to
artificial grassland for supplementary forage to develop barn-feeding livestock hus-
bandry. This provides a great space and potential for the innovation of dryland crop-
ping system, and its combination with animal husbandry in dryland area.
The fourth zone belongs to the most fragile ecological system. It is usually
located at the hilltop area, where rainwater is frequently lost. Other characteristics
of this zone include lacking runoff availability from another area, strong wind, low
air temperatures, relative low soil temperature, low fertility and water retention abil-
ity. This zone is not possible to sustain higher crop productivity and is unsuitable for
agricultural use. To achieve high vegetation coverage and control soil erosion, fenc-
ing can be done to restore natural vegetation and increase vegetation coverage (Sun
et al. 2015 ).
In this complex landscape ecosystem, as a whole, the first, second and third
zones are in an elastic system, which can be closely linked with each other via rota-
tion system. The proportions of cash crop, grain crop, grassland/pasture for live-
stock husbandry will be adjusted according to market quotations. Importantly, this
strategy can help maintain soil fertility equilibrium, and thereby control soil ero-
sion, and ultimately achieve the more balanced development between vegetation
restoration, soil quality improvement and economic boost.
Predictably, in the program of this agroecosystem model, the efficient rainwater
use based intensive dryland agriculture productivity will be achieved within the first
and second zones. Under such a base, the economic benefits will also be signifi-
cantly improved. In the third and fourth zones, the grasslands with the aim to
develop animal husbandry is considered as the main vegetation cover landscape and
land use pattern. This design was made in accordance with the principles of ecologi-
cal zone distribution of natural vegetation and agricultural system. In this integrated
landscape model, the diversity of ecosystems and the development of agricultural
industry were maintained simultaneously. In the meantime, biodiversity and indus-
trial diversity were increased synchronously. As a whole, the ecosystem can be kept
at a stable state, in which agricultural system, livestock husbandry system and eco-
nomic system would obtain stronger flexibility. Therefore, this model diagram of
dryland agro-ecosystem as an innovative theoretical framework for regional devel-
opment acts as a general methodology to guide restore the degraded dryland ecosys-
tem (Sun et al. 2015 ), and coordinate the development of economic, social and
ecological systems in dryland agricultural area.
F.-M. Li et al.