Urochondra setulosa （Trin.） C.E. Hubbard is a coastal halophytic grass thriving on the coastal dunes along the Pakistani seashore. This grass could be useful in coastal sand dune stabilization using seawater irrigat...Urochondra setulosa （Trin.） C.E. Hubbard is a coastal halophytic grass thriving on the coastal dunes along the Pakistani seashore. This grass could be useful in coastal sand dune stabilization using seawater irrigation. The purpose of this investigation was to test the hypothesis that Ca^2＋ （0.0, 2.5, 5.0, 10.0 and 50.0 mmol/L） alleviates the adverse effects of KC1, MgSO4, NaC1 and Na2SO4 at 0, 200, 400, 600, 800 and 1000 mmol/L on the germination of Urochondra setulosa. Seed germination was inhibited with increase in salt concentration with few seeds germinated at and above 400 mmol/L concentration. No seed germinated in any of the KC1 treatments. Inclusion of CaC12 substantially alleviated the inhibitory effects of all salts. Germination was higher under photoperiod in comparison to those seeds germinated under complete darkness. Among the CaC12 concentrations used, 10 mmol/L was most effective in alleviating salinity effects and allowing few seeds to germinate at 1000 mmol/L KC1, MgSO4, NaC1 and Na2SO4 solution.展开更多
Our objectives are to examine the effects of hummock-depression spatial heterogeneity on plant communities and soil properties,and to understand the process of maintaining and adjusting microtopography-mediated hydrol...Our objectives are to examine the effects of hummock-depression spatial heterogeneity on plant communities and soil properties,and to understand the process of maintaining and adjusting microtopography-mediated hydrological inputs and their spatial fluctuations that produce obvious microhabitats.We set up 36 plots(1 m×1 m)and sampled 45 plant and 225 soil samples in flooded(FH)and non-flooded hummocks(NFH)and depressions of the marshy,and the surrounding non-wetland meadows as well as in the Yellow River Source Zone,west China.We evaluated whether the alpine marshy wetland has a fertile island effect by the comparison method.Our results show that hummock presence can increase the spatial heterogeneity of the microhabitat and promote the plant diversity and soil fertility of the Kobresia tibetica community.Plant height,coverage,above-ground biomass,species richness and diversity were significantly higher in the FH and NFH microhabitat than in the areas between hummocks and surrounding non-wetland meadows.Compared with broad alpine meadows,the hummock-depression complex provided a microhabitat favorable to the growth of Cyperaceae.In the 0-50 cm soil layer,the closer the soil layer was to the ground surface,the higher its soil organic carbon and total nitrogen contents.Thus,in deeper layers,the gap between soil nutrients in wetland hummock-depression microhabitat and in the surrounding alpine meadows becomes smaller.Hence,the wetland hummock-depression microhabitat formed a fertile island pattern.Therefore,these results contribute toward improving our understanding of ecosystem restoration in alpine marshy meadows.展开更多
基金Project supported by the 16th Pakistan-China Cooperation Project(Study on Sustainable Halophytes Utilization, No. 16-413)
文摘Urochondra setulosa （Trin.） C.E. Hubbard is a coastal halophytic grass thriving on the coastal dunes along the Pakistani seashore. This grass could be useful in coastal sand dune stabilization using seawater irrigation. The purpose of this investigation was to test the hypothesis that Ca^2＋ （0.0, 2.5, 5.0, 10.0 and 50.0 mmol/L） alleviates the adverse effects of KC1, MgSO4, NaC1 and Na2SO4 at 0, 200, 400, 600, 800 and 1000 mmol/L on the germination of Urochondra setulosa. Seed germination was inhibited with increase in salt concentration with few seeds germinated at and above 400 mmol/L concentration. No seed germinated in any of the KC1 treatments. Inclusion of CaC12 substantially alleviated the inhibitory effects of all salts. Germination was higher under photoperiod in comparison to those seeds germinated under complete darkness. Among the CaC12 concentrations used, 10 mmol/L was most effective in alleviating salinity effects and allowing few seeds to germinate at 1000 mmol/L KC1, MgSO4, NaC1 and Na2SO4 solution.
基金Thank the members of the research team for their kind support in the experiment,and thank the Science and Technology Department of Qinghai Provincial for the funding of the application basic project(2019-ZJ-7035)Discipline Innovation and Introducing Talents Program of Higher Education Institutions(the 111 Project,D18013)Changjiang Scholars and Innovation Team Development plan(IRT_17R62).
文摘Our objectives are to examine the effects of hummock-depression spatial heterogeneity on plant communities and soil properties,and to understand the process of maintaining and adjusting microtopography-mediated hydrological inputs and their spatial fluctuations that produce obvious microhabitats.We set up 36 plots(1 m×1 m)and sampled 45 plant and 225 soil samples in flooded(FH)and non-flooded hummocks(NFH)and depressions of the marshy,and the surrounding non-wetland meadows as well as in the Yellow River Source Zone,west China.We evaluated whether the alpine marshy wetland has a fertile island effect by the comparison method.Our results show that hummock presence can increase the spatial heterogeneity of the microhabitat and promote the plant diversity and soil fertility of the Kobresia tibetica community.Plant height,coverage,above-ground biomass,species richness and diversity were significantly higher in the FH and NFH microhabitat than in the areas between hummocks and surrounding non-wetland meadows.Compared with broad alpine meadows,the hummock-depression complex provided a microhabitat favorable to the growth of Cyperaceae.In the 0-50 cm soil layer,the closer the soil layer was to the ground surface,the higher its soil organic carbon and total nitrogen contents.Thus,in deeper layers,the gap between soil nutrients in wetland hummock-depression microhabitat and in the surrounding alpine meadows becomes smaller.Hence,the wetland hummock-depression microhabitat formed a fertile island pattern.Therefore,these results contribute toward improving our understanding of ecosystem restoration in alpine marshy meadows.
