4.3 Land use conversion characteristics and wild tending areas
planning in the climate-stable areas of T. chinense
Human activities are a major factor leading to global change, which
overwhelm the natural changes brought about by climate change in the
past few thousand years (Houghton et al., 1990). Human activities such
as agriculture, forestry, and other land management have changed the
entire landscape, thus affecting the flora and fauna communities of many
ecosystems worldwide (Ojima et al., 1994). In China, the climate-stable
areas of T. chinense are mainly distributed in humid and
semi-humid areas, and the major changes of land use types in this area
in the future are mainly construction land and grassland. It is
predicted that the construction land in the region will expand rapidly
in the next hundred years, an increase of about 46.94% compared with
2015. The distribution of construction land is mainly related to
population density. Future population projections indicate that although
the proportion of the population in the southeast of China will decrease
over the next 20 years, the change will only be between 0.1% and 0.3%
(L. Wang et al., 2014). Although the overall pattern of spatial
population distribution in China will not change fundamentally, with the
southeast being densely populated and the northwest being sparsely
populated, the scale and degree of population agglomeration in urban
agglomerations are gradually increasing, and the trend of population
agglomeration is more obvious (L. Wang et al., 2014) Therefore, this
study predicted that the rapid growth of the construction land ofT. chinense in the future climate-stable areas in China is in
line with the actual situation.
In addition to the rapidly expanding construction land, the grassland
areas in the climate-stable areas have also changed significantly, and
their areas have decreased by 15.18% compared with 2015. Grassland
ecosystem is the largest ecosystem in land surface types and occupies an
extremely important role in the terrestrial ecosystem. The impact of
human activities on the grassland ecological system in recent years
growing (X. Zhang et al., 2022). Since the 21st century, the Chinese
government has invested vigorously in ecological restoration projects
and carried out ecological restoration work, such as returning farmland
to grassland, which significantly affects the restoration of grassland
soil nutrients (carbon) (C. Chen et al., 2019). In the climate-stable
areas of T. chinense in the next hundred years, there will be no
such transfer from 2050 to 2090, except that a small amount of
cultivated land will be transferred to grassland from 2015 to 2050.
Therefore, the soil nutrients restored by returning cultivated land to
grassland in the next hundred years will be very low. In the future, the
areas of construction land transferred to grassland in the region will
increase yearly. It is estimated that by 2090, the areas of construction
land transferred from 2070 will account for about 1.22% of the
grassland areas in 2090. Large scale construction projects have not only
seriously damaged grassland vegetation and topsoil, resulting in a sharp
decline in grassland carbon storage, which will take many years to
recover, but also exacerbated climate change and indirectly affected
grassland ecosystem, causing a certain impact (X. Chen & Shang, 2011).
Therefore, in the context of future climate change and land use change,
the natural habitat suitable for the growth of T. chinense will
face a huge threat.
Under land use and climate change, although climate change increases the
total suitable areas of T. chinense , it will seriously threaten
the high suitable areas. In the climate-stable area of T.
chinense under different climate scenarios, the habitat areas suitable
for the growth of T. chinense will gradually reduce due to the
change in land use. These future changes may limit the expansion of wild
populations. Furthermore, combined with excessive harvesting, wild
resources are increasingly depleted, making it difficult for the species
to continue. At present, wild resources can not meet the needs of
medicine, but its artificial breeding technology is not mature. And
according to the Non-grain Production policy in China, cultivated land
is forbidden to grow economic crops. Therefore, it is necessary to carry
out wild tending of T. chinense , which can promote the recovery
and sustainable utilization of T. chinense population. Wild
tending is an available approach to solve the contradiction between the
shortage of wild resources of medicinal plants and the large market
demand. It is a production mode of artificially or naturally increasing
the population of target medicinal materials, which can not only greatly
increase the available resources, but also maintain the community
balance after over-collecting, and continuously supply genuine-quality
medicinal materials (S. Chen et al., 2004). The wild tending area has
the characteristics of primitive environment, less human intervention
and far away from pollution sources. It is very important to predict the
change range of the suitable habitat of T. chinense for
formulating agricultural policies and planting planning (Shen et al.,
2021). Based on the current high suitable areas of T. chinense in
China, combined with the future climate and land use change, this study
planned the wild tending areas of T. chinense for hundred years.
This can effectively avoid the huge economic losses caused by blind
planting. According to the results of the wild tending area, we made the
following recommendations: (1) The wild tending areas of T.
chinense in China are mainly distributed in the north, northeast, and
southwest of China. In the future, most of the areas will be high
suitable area, and only a few areas will be transformed into medium or
low suitable areas. It is suggested that germplasm collection and
diversity evaluation of wild plants should be carried out in the climate
transformation areas, which is conducive to the conservation and
domestication of the core germplasm of T. chinense . (2) The local
government should take more actions to protect the natural ecology,
enhance the awareness of the protection and restoration of local natural
land types, and avoid irreversible damage to them. (3) The planned wild
tending area of T. chinense should be combined with local
policies, integrate ecological, economic, and social benefits, and
strengthen the establishment of wild tending medicinal material bases.
This will effectively solve the contradiction between T. chinenseecological protection and biodiversity, resources and supply demand. (4)
The precondition of artificial breeding and wild tending is to master
the basic characteristics of growth and development of TCM. Therefore,
we should strengthen the research on population ecology and
developmental biology, especially on the influence of different hosts on
the composition and the mixed cultivation mode with other crops. This
can not only maintain the stability of T. chinense population,
but also improve the quality and yield of T. chinense . At the
same time, the mixed cultivation mode can effectively make full use of
land resources and make up for the shortage of grassland resources in
some areas due to the dense population.