Growth response of broom (Cytisus scoparius) growing with and without radiata pine (Pinus radiata) seedlings to different P levels in soils

A study was carried out to test the effects of three rates of TSP （triple superphosphate） （0, 50, and 100 mg·kg^-1 P） on growth of broom with and without radiata pine seedlings and to determine the relationships between P concentrations in the broom shoot and dry matter yields with soil plant-available P （Bray-2 P）. A bulk sample of soil was collected from Kaweka forest at soil depth of 0-10 cm, in New Zealand on March 11, 2001. The forest area was not supplied with fertiliser at least 30 years. The results show that TSP application increased P avail- ability in the soil. The P availability concentration in soil of broom with radiata pine seedlings was higher than that in soil of broom alone. Bray-2 P concentrations had a significant logarithmic relationship with Pcon- centrations of broom shoot and an exponential relationship with dry matter weight of whole broom plant.

Scopariusols L–T, nine new ent-kaurane diterpenoids isolated from Isodon scoparius

Nine new ent-kaurane diterpenoids, named scopariusols L–T(1–9), were isolated from the aerial parts of Isodon scoparius. Their structures were characterized mainly by analyzing the NMR and HR-ESI-MS data, and the absolute configuration of 1 was determined by single-crystal X-ray diffraction. Compound 1 was active against five human tumor cell lines(HL-60, SMMC-7721, A-549, MCF-7, and SW-480), and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with an IC50 value of 0.6 μmol·L-1.

Phosphorus fractions of fertiliser-derived P in an allophanic soil under Pinus radiata seedlings grown with broom and ryegrass

Changes in phosphorus （P） fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom （Cytisus scoparius L.） and ryegrass （Lolium multiflorum） in pots were studied 14 months after the application of triple superphosphate at the rates of 0, 50, and 100 pg.g^-1, to determine the fate of fertiliser-derived P in the rhizosphere soils. Application of P fertiliser increased NaOH-Pi, NaOH-Po, and H2SO4-Pi concentrations in the soil, but decreased the residual-P concentration. The resin-Pi concentration, which is ex- tremely low in this soil （1 to μgg^-1 ）, remained the same. The majority of the added fertiliser P was however recovered in the NaOH-Pi fraction （40%-49%）. This is due to the high P fixation in this soil （92%）. The second highest P recovery was in NaOH-Po fraction （7%-19%）. Under P deficient condition or addition at the rate of 0 μg.g^-6, the NaOH-Pi concentration in the radiata rhizosphere soil was lower than that in the bulk soil and broom and grass rhizosphere soils. This may be due to higher oxalate production by the roots and mycorrhiza under P deficient conditions which released some ＆the P fixed to the soils in the rhizosphere, which needs to be tested in future studies.

伴生有金雀花、黑麦草的辐射松幼苗Allophanic土壤磷肥驱动的各磷形态变化

Changes in phosphorus (P) fractions in a P deficient allophanic soil under P. radiata seedlings grown with broom (Cytisus scoparius L.) and ryegrass (Lolium multiflorum) in pots were studied 14 months after the application of triple superphosphate at the rates of 0, 50, and 100 μg·g-1, to determine the fate of fertiliser-derived P in the rhizosphere soils. Application of P fertiliser increased NaOH-Pi, NaOH-Po, and H2SO4-Pi concentrations in the soil, but decreased the residual-P concentration. The resin-Pi concentration, which is extremely low in this soil (1 to 3 μg·g-1 ), remained the same. The majority of the added fertiliser P was however recovered in the NaOH-Pi fraction (40%?49%). This is due to the high P fixation in this soil (92%). The second highest P recovery was in NaOH-Po fraction (7%?19%). Under P deficient condition or addition at the rate of 0 μg·g-1, the NaOH-Pi concentration in the radiata rhizosphere soil was lower than that in the bulk soil and broom and grass rhizosphere soils. This may be due to higher oxalate production by the roots and mycorrhiza under P deficient conditions which released some of the P fixed to the soils in the rhizosphere, which needs to be tested in future studies.

Informing management of rare species with an approach combining scenario modeling and spatially explicit risk assessment

Wildlife managers are tasked with identifying and managing stressors that threaten persistence of populations.We demonstrate an approach to land-use planning that combines scenario modeling and ecological risk assessment to map and quantify risk to population persistence for three rare prairie species in Washington State,USA.Following corroboration of model output,we found that of the management scenarios considered,only a scenario with year-round restrictions on use of off-road vehicles,digging,and camping enforced in all potential habitat reduces risk to the species.Decreased risk is focused primarily in two patches of prairie habitat in our study area,indicating stringent restrictions need not be applied broadly.However,one area is not easily accessed by two of the three species considered,suggesting reintroductions to suitable but inaccessible habitat may play an important role in management of these species.Our analyses suggest changes in land use and management that might improve habitat for rare species,with options for minimizing monetary and social costs.Because the proposed approach relies on hypothetical management scenarios and uses a model flexible in data requirements to provide spatially explicit output,it can be used to inform adaptive management of rare species in diverse land-planning processes and will be especially useful when management decisions must be made under time or cost constraints.