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The partitioning patterns of nutrients between pods and seeds of Zanthoxylum fruits impacted by environmental factors

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Acta Geochimica 2018年第5期37卷 676-683页

作者： Hechun Piao Siliang Li Zhifeng Yan State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Institute of Surface-Earth System Science Tianjin University

The nutritive quality in plant organs is related to the different partitioning patterns of nutrient resources among the organs under various environmental *** study examined the relationship between the nutritive quality of pods and seeds in Zanthoxylum and environmental factors, such as temperature and preciptation by using numerous samples collected from Southwest China to the East China of Shandong peninsula. The increasing accumulations of N, P and C in seeds implied that the nutritive quality in seeds was higher at the regions with relative higher mean annual temperature(MAT) and mean annual precipitation(MAP), while that in pods was on the contrary. By contrast, pod nutritive content was relatively high, but seed nutritive content was relatively low at the regions with relative high MAT and MAP. In addition, C:N ratio in pods was significantly and negatively correlated with MAT and MAP, while that in seed was significantly and positively correlated with MAT and MAP. The partitioning patterns of N-compounds between pods and seeds reflected different nitrogen translocations in the plant organs under various climate condition. The N:P ratios were negatively correlated with MAP, implying a higher proportional allocation of P to seeds than that of N in the areas with a relative high MAP. Therefore, the strategies to assess pod nutritional quality should be taken into accountfor nutritive translocation under various environmental conditions.

关键词： Partitioning pattern Nutritional quality C:Nratio Zanthoxylum fruits mean annual temperature mean annual precipitation

Late Pleistocene spore-pollen record and climatic change at the Chongphadae Cave Site,Democratic People's Republic of Korea

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Journal of Palaeogeography 2023年第4期12卷 624-636页

作者： Se Chan Kim Rye Sun Choe Il Nam Kim Chol U Ryong Il Kang Institute of Human Evolution and Development History Faculty of HistoryKim Il Sung UniversityTaesong DistrictPyongyangDemocratic People's Republic of Korea

We present a detailed pollen record and interpretations of late Pleistocene climatic change at the Chongphadae Cave Site, Democratic People's Republic of Korea. The mean annual paleotemperature and mean annual paleoprecipitation of the site were calculated using the temperature index and precipitation index based on ecological features and geographical distribution of each taxon. temperature index and precipitation index range from 8.8℃ to 10.4℃ and from 805.0 mm to 963.1 mm, respectively. Four dates(radiocarbon, uranium series, fission track, and paleomagnetic excursion dating) of the deposit profile investigated yield a range of ~21.3 ka BP to ~117 ka BP, geochronologically corresponding to the late Pleistocene, and extend from the last interglacial highstand through the Last Glacial Maximum. Our results are thus consistent with the climatic shift from interglacial to glacial conditions, provide evidence that the environments of the region, which was reconstructed from the paleoclimatic index, changed from a mild and humid to a cool and dry climate during the late Pleistocene, and suggest trends similar to those of several parts of the Northern Hemisphere which lie in the same latitudinal zone as our study area.

关键词： Chongphadae cave Pollen Climatic change Late Pleistocene mean annual temperature mean annual precipitation

Evaluating the grassland net primary productivity of southern China from 2000 to 2011 using a new climate productivity model

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Journal of Integrative Agriculture 2016年第7期15卷 1638-1644页

作者： SUN Cheng-ming ZHONG Xiao-chun CHEN Chen GU Ting CHEN Wen Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops Yangzhou University Institute of Agriculture Information Chinese Academy of Agricultural Sciences

Grassland is the important component of the terrestrial ecosystems. Estimating net primary productivity （NPP） of grassland ecosystem has been a central focus in global climate change researches. To simulate the grassland NPP in southern China, we built a new climate productivity model, and validated the model with the measured data from different years in the past. The results showed that there was a logarithmic correlation between the grassland NPP and the mean annual temperature, and there was a linear positive correlation between the grassland NPP and the annual precipitation in southern China. Al these results reached a very signiifcant level （P〈0.01）. There was a good correlation between the simulated and the measured NPP, withR2 of 0.8027, reaching the very signiifcant level. meanwhile, both root mean square errors （RMSE） and relative root-mean-square errors （RRMSE） stayed at a relatively low level, showing that the simulation results of the model were reliable. The NPP values in the study area had a decreasing trend from east to west and from south to north, and the mean NPP was 471.62 g C m？2 from 2000 to 2011. Additionaly, there was a rising trend year by year for the mean annual NPP of southern grassland and the tilt rate of the mean annual NPP was 3.49 g C m？2 yr？1 in recent 12 years. The above results provided a new method for grassland NPP estimation in southern China.

关键词： grassland NPP estimation model annual precipitation mean annual temperature southern China

Carbon and Nitrogen Storage in Inner Mongolian Grasslands: Relationships with Climate and Soil Texture

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Pedosphere 2014年第3期24卷 391-398页

作者： HE Nian-Peng WANG Ruo-Meng ZHANG Yun-Hai CHEN Quan-Sheng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences

Understanding the spatial variability of soil carbon （C） storage and its relationship with climate and soil texture is critical for developing regional C models and for predicting the potential impact of climate change on soil C storage. On the basis of soil data from a transect across the Inner Mongolian grasslands, we determined the quantitative relationships of C and nitrogen （N） in bulk soil and particle-size fractions （sand, silt, and clay） with climate and soil texture to evaluate the major factors controlling soil C and N storage and to predict the effect of climate changes on soil C and N storage. The contents of C and N in the bulk soil and the different fractions in the 0 20 and 20 40 cm soil layers were positively correlated with the mean annum precipitation （MAP） and negatively correlated with the mean annual temperature （MAT）. The responses of C storage in the soil and particle-size fractions to MAP and MAT were more sensitive in the 0-20 cm than in the 2（~40 cm soil layer. Although MAP and MAT were both important factors influencing soil C storage, the models that include only MAP could well explain the variation in soil C storage in the Inner Mongolian grasslands. Because of the high correlation between MAP and MAT in the region, the models including MAT did not significantly enhance the model precision. Moreover, the contribution of the fine fraction （silt and clay） to the variation in soil C storage was rather small because of the very low fine fraction content in the Inner Mongolian grasslands.

关键词： mean annual precipitation mean annual temperature native grassland particle-size fraction soil organic matter

Mismatch between species distribution and climatic niche optima in relation to functional traits

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Forest Ecosystems 2022年第6期9卷 813-822页

作者： Zhenghua Lian Juan Wang Chunyu Zhang Xiuhai Zhao Klaus von Gadow Research Center of Forest Management Engineering of State Forestry and Grassland Administration Beijing Forestry UniversityBeijing100083China Department of Forest Ecology School of Ecology and Nature ConservationBeijing Forestry UniversityBeijing100083China Faculty of Forestry and Forest Ecology Georg-August-University GottingenBüsgenweg 5D-37077GottingenGermany Department of Forest and Wood Science University of StellenboschStellenbosch7600South Africa

Background:Forecasts of climate change impacts on biodiversity often assume that the current geographical distributions of species match their niche ***,empirical evidence has challenged this assumption,suggesting a *** examine whether the mismatch is related to functional traits along temperature or precipitation ***:The observed distributions of 32 tree species in northeast China were evaluated to test this *** models were used to estimate the climatic niche optima,*** habitats where the highest species growth and density can be *** mismatch is defined as the difference between the actual species occurrence in an assumed niche optimum and the habitat with the highest probability of species ***’functional traits were used to explore the mechanisms that may have caused the ***:Contrasting these climatic niche optima with the observed species distributions,we found that the distribution-niche optima mismatch had high variability among species based on temperature and precipitation ***,these mismatches depended on functional traits associated with competition and migration lags only in temperature ***:We conclude that more relevant research is needed in the future to quantify the mismatch between species distribution and climatic niche optima,which may be crucial for future designs of forested landscapes,species conservation and dynamic forecasting of biodiversity under expected climate change.

关键词： Demography Functional traits mean annual temperature mean annual precipitation Niche theory Species distribution

Variations of root and heterotrophic respiration along environmental gradients in China’s forests

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Journal of Plant Ecology 2013年第5期6卷 358-367页

作者： Pin Li Yuanhe Yang Jingyun Fang Department of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Aims Root and heterotrophic respiration may respond differently to environmental variability,but little evidence is available from largescale *** we aimed to examine variations of root and heterotrophic respiration across broad geographic,climatic,soil and biotic *** We conducted a synthesis of 59 field measurements on root and heterotrophic respiration across China’s *** Findings Root and heterotrophic respiration varied differently with forest types,of which evergreen broadleaf forest was significantly different from those in other forest types on heterotrophic respiration but without statistically significant differences on root *** results also indicated that root and heterotrophic respiration exhibited similar trends along gradients of precipitation,soil organic carbon and satellite-indicated vegetation ***,they exhibited different relationships with temperature:root respiration exhibited bimodal patterns along the temperature gradient,while heterotrophic respiration increased monotonically with ***,they showed different relationships with MOD17 GPP,with increasing trend observed for root respiration whereas insignificant change for heterotrophic *** addition,root and heterotrophic respiration exhibited different changes along the age sequence,with insignificant change for root respiration and decreasing trend for heterotrophic ***,these results suggest that root and heterotrophic respiration may respond differently to environmental *** findings could advance our understanding on the different environmental controls of root and heterotrophic respiration and also improve our ability to predict soil CO_(2) flux under a changing environment.

关键词： enhanced vegetation index forest age heterotrophic respiration latitude mean annual temperature mean annual precipitation root respiration GPP