Environmental variations and ontogeny may affect plant morphological traits and biomass allocation patterns that are related to the adjustments of plant ecological strategies. We selected 2-, 3-and 4-year-old Fritilla...Environmental variations and ontogeny may affect plant morphological traits and biomass allocation patterns that are related to the adjustments of plant ecological strategies. We selected 2-, 3-and 4-year-old Fritillaria unibracteata plants to explore the ontogenetic and altitudinal changes that impact their morphological traits(i.e., plant height, single leaf area,and specific leaf area) and biomass allocations [i.e.,biomass allocations of roots, bulbs, leaves, stems, and flowers] at relatively low altitudinal ranges(3400 m to 3600 m asl) and high altitudinal ranges(3600 m to4000 m asl). Our results indicated that plant height,root biomass allocation, and stem biomass allocation significantly increased during the process of individual growth and development, but single leaf area, specific leaf area, bulb biomass allocation, and leaf biomass allocation showed opposite trends.Furthermore, the impacts of altitudinal changes on morphological traits and biomass allocations had no significant differences at low altitude, except for single leaf area of 2-year-old plants. At high altitude,significantly reduced plant height, single leaf area and leaf biomass allocation for the 2-year-old plants,specific leaf area for the 2-and 4-year-old plants, and stem biomass allocation were found along altitudinal gradients. Significantly increased sexual reproductive allocation and relatively stable single leaf area and leaf biomass allocation were also observed for the 3-and 4-year-old plants. In addition, stable specific leaf area for the 3-year-old plants and root biomass allocation were recorded. These results suggested that the adaptive adjustments of alpine plants, in particular F. unibracteata were simultaneously influenced by altitudinal gradients and ontogeny.展开更多
Fragmentation and loss of habitats due to natural disasters, like earthquakes and earthquaketriggered debris flows are existing threats to the long- term survival of the giant panda （Ailuropoda melanoleuca）. To bett...Fragmentation and loss of habitats due to natural disasters, like earthquakes and earthquaketriggered debris flows are existing threats to the long- term survival of the giant panda （Ailuropoda melanoleuca）. To better understand natural recovery processes of the damaged habitat, field investigation and laboratory analysis were used to analyze relationships between plant colonization and soil characteristics in an over 3o-year natural recovery of a damaged giant panda habitat in a debris flow gully after the 1976 Songpan-Pingwu earthquake in Sichuan Province, China. Four different damaged sites were selected that located at the center of the gully （center）, on a flat alluvial fan （fan）, in a side slope of the gully （slope）, and at the ecotone between the gully and native forest （ecotone）. Vegetation characteristics, soil physicochemical properties, and microbial biomass in the different sites and soil depths were measured. After the natural recovery, the soil fertility, water retention, and microbial biomass were highest at ecotone, followed by fan, slope, and center. Only a few perennial herbs colonized at center; shrubs started to invade at fan and slope, and the native trees dominated the community of ecotone. Furthermore, Fargesia spathacea （food for the giant panda） started to be re-established at ecotone, and the community characteristic of ecotone recovered similarly to the native habitat. These results suggested that improving the soil fertility, water retaining capacity and microbial biomass is fundamental to the plant colonization, particular for F. spathacea＇s re- establishment in a damaged giant panda habitat.展开更多
The tiller emergence in seedling nursery beds and field, and panicle formation in the field were investigated under scattered-planting with seedling dry-raised on plastic trays in double-season rice. A significant dif...The tiller emergence in seedling nursery beds and field, and panicle formation in the field were investigated under scattered-planting with seedling dry-raised on plastic trays in double-season rice. A significant difference was noted in the non-synchronously-emerged tillers （the tillers that formed from latent buds and did not emerge following the normal tillering law on seedling nursery beds and recovered to grow after scattered-planting or transplanting） as well as the percentage of the available synchronously-emerged tillers between seedlings raised on plastic trays under dry-land conditions （DPT） and seedlings raised on nursery beds under wetland conditions （WB）. The seedlings under DPT had some non-synchronously-emerged tillers, but those under WB had not. Therefore, the traditional formula for determining the number of rice seedlings was improved, and the formula for determining the number of basic seedlings under scattered planting with DPT in double-season rice was introduced. For early rice, it was X=Y/{（I＋t1r1）[1＋（N-n-SN）Rr2]＋（SN-3-t1）R2r5}, and for late rice, it was X=Y/{（1＋t1r1）[1＋（N-n-SN）Rr2]＋（N-n-SN-3）Rr2R1r3＋（SN-3-t1）R2r5}. Where, X represents reasonable number of basic seedlings per unit area at scattered-planting; Y, number of fitting panicles per unit area; t1, total number of tillers per plant; r1, percentage of the total available tillers; N, total number of leaves of the main culm; n, total number of elongated internodes in the main culm; SN, seedling leaf ages at scattered-planting; R, percentage of the primary tillers emerged in available node-position; r2, percentage of the available primary tillers; R1, percentage of the secondary tillers in the field （except the secondary tillers of the seedlings）; r3, percentage of the available secondary tillers; R2, percentage of the asynchronously-emerged tillers after scattered-planting; r5, percentage of the available non-synchronously-emerged tillers after scattered-planting.展开更多
基金supported by the Key-Area Research and Development Program of Guangdong Province(2020B090919005)the National Natural Science Foundation of China(21975274 and 52101276)+4 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA22010600)Shandong Provincial Natural Science Foundation(ZR2020KE032 and ZR2022QB160)the Youth Innovation Promotion Association of CAS(2021210)the Shandong Energy Institute(SEI)(SEI I202117)Parts of the work were also supported by the BMWi/BMWK project HiBrain(03ET039G)。
基金funded by the Natural Science Foundation Project of Sichuan Science and Technology Department (2018JY0305)Key Projects of the Natural Science Foundation of Sichuan Education Department (18ZA0002)
文摘Environmental variations and ontogeny may affect plant morphological traits and biomass allocation patterns that are related to the adjustments of plant ecological strategies. We selected 2-, 3-and 4-year-old Fritillaria unibracteata plants to explore the ontogenetic and altitudinal changes that impact their morphological traits(i.e., plant height, single leaf area,and specific leaf area) and biomass allocations [i.e.,biomass allocations of roots, bulbs, leaves, stems, and flowers] at relatively low altitudinal ranges(3400 m to 3600 m asl) and high altitudinal ranges(3600 m to4000 m asl). Our results indicated that plant height,root biomass allocation, and stem biomass allocation significantly increased during the process of individual growth and development, but single leaf area, specific leaf area, bulb biomass allocation, and leaf biomass allocation showed opposite trends.Furthermore, the impacts of altitudinal changes on morphological traits and biomass allocations had no significant differences at low altitude, except for single leaf area of 2-year-old plants. At high altitude,significantly reduced plant height, single leaf area and leaf biomass allocation for the 2-year-old plants,specific leaf area for the 2-and 4-year-old plants, and stem biomass allocation were found along altitudinal gradients. Significantly increased sexual reproductive allocation and relatively stable single leaf area and leaf biomass allocation were also observed for the 3-and 4-year-old plants. In addition, stable specific leaf area for the 3-year-old plants and root biomass allocation were recorded. These results suggested that the adaptive adjustments of alpine plants, in particular F. unibracteata were simultaneously influenced by altitudinal gradients and ontogeny.
基金funded by the National Natural Science Foundation Project of China(Grant No.31100358)the Ministry of Science and Technology of China(Grant No.2011BAC09B0404)
文摘Fragmentation and loss of habitats due to natural disasters, like earthquakes and earthquaketriggered debris flows are existing threats to the long- term survival of the giant panda （Ailuropoda melanoleuca）. To better understand natural recovery processes of the damaged habitat, field investigation and laboratory analysis were used to analyze relationships between plant colonization and soil characteristics in an over 3o-year natural recovery of a damaged giant panda habitat in a debris flow gully after the 1976 Songpan-Pingwu earthquake in Sichuan Province, China. Four different damaged sites were selected that located at the center of the gully （center）, on a flat alluvial fan （fan）, in a side slope of the gully （slope）, and at the ecotone between the gully and native forest （ecotone）. Vegetation characteristics, soil physicochemical properties, and microbial biomass in the different sites and soil depths were measured. After the natural recovery, the soil fertility, water retention, and microbial biomass were highest at ecotone, followed by fan, slope, and center. Only a few perennial herbs colonized at center; shrubs started to invade at fan and slope, and the native trees dominated the community of ecotone. Furthermore, Fargesia spathacea （food for the giant panda） started to be re-established at ecotone, and the community characteristic of ecotone recovered similarly to the native habitat. These results suggested that improving the soil fertility, water retaining capacity and microbial biomass is fundamental to the plant colonization, particular for F. spathacea＇s re- establishment in a damaged giant panda habitat.
文摘The tiller emergence in seedling nursery beds and field, and panicle formation in the field were investigated under scattered-planting with seedling dry-raised on plastic trays in double-season rice. A significant difference was noted in the non-synchronously-emerged tillers （the tillers that formed from latent buds and did not emerge following the normal tillering law on seedling nursery beds and recovered to grow after scattered-planting or transplanting） as well as the percentage of the available synchronously-emerged tillers between seedlings raised on plastic trays under dry-land conditions （DPT） and seedlings raised on nursery beds under wetland conditions （WB）. The seedlings under DPT had some non-synchronously-emerged tillers, but those under WB had not. Therefore, the traditional formula for determining the number of rice seedlings was improved, and the formula for determining the number of basic seedlings under scattered planting with DPT in double-season rice was introduced. For early rice, it was X=Y/{（I＋t1r1）[1＋（N-n-SN）Rr2]＋（SN-3-t1）R2r5}, and for late rice, it was X=Y/{（1＋t1r1）[1＋（N-n-SN）Rr2]＋（N-n-SN-3）Rr2R1r3＋（SN-3-t1）R2r5}. Where, X represents reasonable number of basic seedlings per unit area at scattered-planting; Y, number of fitting panicles per unit area; t1, total number of tillers per plant; r1, percentage of the total available tillers; N, total number of leaves of the main culm; n, total number of elongated internodes in the main culm; SN, seedling leaf ages at scattered-planting; R, percentage of the primary tillers emerged in available node-position; r2, percentage of the available primary tillers; R1, percentage of the secondary tillers in the field （except the secondary tillers of the seedlings）; r3, percentage of the available secondary tillers; R2, percentage of the asynchronously-emerged tillers after scattered-planting; r5, percentage of the available non-synchronously-emerged tillers after scattered-planting.
