The bio-ecololgical characters of Achnatherum splendens (Trin) and its cultivation techniques
by Cheng Jimin and Du Feng
(Institute of soil and water conservation , Chinese Academy of Sciences and Ministry of Water Resources, 26 Xinong Road YangLing , Shaanxi, China 712100)
1. Bio-ecological characters
chnatherum splendens (Trin) is a perennial that grows into a thickl and compact clump with a 0.3-1.0m diameter, it has tough and erect stem, 0.5-2.0m high and a persistent base. The yellowish brown leaf sheath is 0.2-0.3m above the ground, the tough and curled leaf blade is 0.4-0.7m long. The pyramid-like panicle is large and is about 0.4-0.65m long, the greyish green or with some purple spikelet is 4.0-6.0 mm long. It blossoms in June or July, and is ripe in August or September. The arista stretch out between the tooth of outside glume, do not twist, but easily fall. The tough and thick root is 0.2-0.3cm in diameter on the average and covered with sand sheath and white hair mycorrhiza. Its root system is large and has a length of 1.6-2.0m. On sandy brown soil, the nodal position of tiller often changes distinctly. In the overgrazing section, the soil is so hard that salt is accumulated on the top and soil drought is accelerated through capilliary action; so much of dead root remains on the profile, live root mass on the top of the profile, subsequent decrease of root mass causes the decrease of the number of tiller, so the clump is broken and its yield decrease accordingly. Splendens is halophytic xeric-mesic grass, usually relative species of halophytic meadow. In the area of typical steppe-desert steppe and desert, we can see that steppe halophytic meadow, desert halophytic meadow and typical meadow halophytic communities inlay it. These communities usually exists slightly halophytic lowland and shallow ditches, sometimes extend to the slightly low topography, halophytic basin and lake fringe. Splendens has strong adaptability and resistance to drought and cold so that it can grow thickly even on barren hills,“steep cliff” saline-alkali lowlands and cobble beach. Under the circumstance of soil with enough water and little air, it can tiller on the ground and grow annually to a big clump. When soil is dry and very halophytic, the clump become less taller and thicker, so its width and density have a large range. Other plants that grow together with Splendens are salt-enduring species, such as Aneurolepidum cladystachys; Suaceda sp.; Clinelymus dahuricus; Plantago asiatica; Chenopodium glaucum and Salsola collina etc. Splendens meadow steppe distribute wildly in Inner Mongolia, Shaanxi, Ningxia, Qinhai, Ganshu and Xingjiang ect. . In Inner Mongolia , it is distributed mainly in the Wulanhuduke no-graze area and river beach and alluvial plain; in Shaanxi, mainly in semi-desert land, valley of Yellow River; in Ningxia region, mainly in the lowland of diluvial plain at eastern foot of Helan Mountain and alluvial plain of Yellow River, mostly in Yingchuan and its north, thickly grow in Pinjibao, Kingshan and advancing farm, distribute mainly in Tongxin, Haiyuan and Xiji county in the south of Ningxia, sparsely in Guyuan county. Its distribution area is roughly plain and 1.5m-depth of ground water, there white salt crystals and agglornerate are always on the surface of most meadow salt soil or salt meadow soil. In Qinghai province, there are about 1,730,000 hm2, 5.3 percent of usable rangeland, mostly in a narrow belt of lowland between Nanshan and Wami mountain, the southeastern part of the Qaidam Basin. It is distribute everywhere in Xingjing region.
2. Biomass and nutrition composition
Its biomass is greatly influenced by the condition of site, usage intensity and closed time From table 1., it can be concluded that soil salt has a great influence to the biomass, which is high in salt-alkali land, low in sandy land. In addition, yield of Splendens (Trin) grassland depend upon the density, that is to say, yields is proportional to the distance between clump. When the distance is 1.2-2.0m, the fresh matter yield can be 6,000 kg per ha highly, some changes may be possible for the influence of soil and condition of site .
Table 1. Changes of splendens (Trin ) biomass under different condition of sites
Site Types Height Diameter Distance between FM
(m) of clump (m) clump (m) (kg/hm2 )
Inner mongolia saline-alkali land in Etuoke county 1.0 0.8 x 0.8 1.0~2.0 6000
Shaanxi saline-alkali sandy land 1.2 0.8 x 0.8 1.2~2.3 5700
Ningxia diluvial fan of Helan mountain 1.5 0.7 x 0.7 1.5~2.5 5100
Ganshu sandy land in Minqin county 0.6 0.5 x 0.5 1.6~2.6 4200
Qinghai Qaidam Basin 0.8 0.5x 0.5 1.5~2.5 4180
Xingjing valley 0.9 0.7 x 0.7 1.0~2.0 5400
In the closed area of Wulate-back county in Inner Mongolia, tillering is restrained by the dry branch and reserved litter for long no use, yield of DM is 1050g per clump, is twice that of FM. This shows that tiller ability is inhibited under the condition of unreasonable usage. On the winter and spring grassland of Inner Mongolia that is grazed intensively, the height of nutritive branch is only 20cm, reproductive branch 35 cm, width of the clump is 50 cm in diameter, only 15 tillers on each clump on the average. On the diluviated fan fringe belt of Helan mountain in Ninxia, what with long-term graze and excavation used for fuel and broom, again with drought climate, low salt content in soil and most of the site is sand and gravel land, communities degenerate seriously and distribute sparsely, 8-10% species per m2, and its coverage is only 15-20% , FM weights 750.0kg/hm2 .
In one word, over use and no use, both cause the clump degenerate, mainly for branching tiller generation and root growth being restrained. When used appropriately, the above ground part grow and reproduce fully, new fibrous root can be observed on the profile of soil, even on the old roots, slim white root hair and ashen yellow lateral root grow out again . Its nutritive value is high, it is analyzed that during tillering, the content of water is 62g/kg, crude protein (CP) 252g/kg, ether extract (EE) 30.1g /kg, crude fibrous (CF) 208g/kg, introgen free extract (IFE) 315g/kg ,crude ash 56.2g/kg, P 3.2g/kg ,Ca 2.2g/kg, carotene 90.25mg/kg; during jointing ,CP decline to 114.2g/kg, EE and CF increase to 40.5g/kg and 408.2g/kg respectively; during fruiting, CP and EE decline to 97.0g/kg and 23.3k/kg respectively, CF increase to 382.4g/kg; when the branch get dry entirely, CP only 42.5g/kg, EE 23.1g/kg, CF 453.2g/kg. Nutritive value reach its climax in jointing stage, at this time it is suitable for use, afterwards it decline for the stem and leaf become old and rough .
3. Usage and economic value
3.1 Conservation of water and soil
Splendens (Trin) has strong adaptability and wide distribution, the exburant root and branch make it possible to fix soil and restrain runoff , so it is suitable for conservation of water and soil. It often grows on the sides of banks and ridges and has strong resistance to trampling (grazing), pest and disease. On the landside and sloping land of pathside, it often grow into grass mound , its regrowth vigor is so strong that its flourishing root and clump can restrain other grass from invading , so its appearance of community is single and stable. At the front, bottom and bank of erosion ditch , it can retain soil and keep the water the soil plaster , restrain the down-erosion of ditch bottom, advancing of ditch front and collapse of ditch bank. It is often used to make the barren hill and slope green and protect road , dam and canal from being scoured .
Splendens (Trin) also has high nutritive value. Big livestocks are fond of eating it before heading. In earlier spring , sheep like to eat, afterwards ox and camel like, after heading, big livestocks are fond of eating its spike. When other grasses get withered, livestocks eat its leaf. It is suitable to use in jointing stage, as its nutritive value reach its climax , branch and leaf is more tender and suitable for livestocks to eat .
3.3 Other usage
It can be used to make high-quality paper paste and artificial silk, to weave basket, cage, curtain, broom, etc., further more, rope made of it is strong and can be used for long time.
4 Cultivation techniques
Splendens(Trin) reproduce asexually in most cases by tillering , sexually less. Planting of it can be either in spring or in autumn. When planted in spring, it is more suitable in earlier time from soil thawing to early May. In autumn, sowing while harvesting seeds is suitable from late September till soil is frozen, sowing depth is 1.5-3.0cm after several harrows. Before or after raining , it is appropriate for root planting in early spring or late autumn. In order to decrease evaporation and nutrition consume to improve the planting seedling growth and its survival rate, cut away stem and leaf is necessary before planting
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