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    题名 作者 年代 出处 被引量
1Engineering a New Chloroplastic Photorespiratory Bypass to In crease Photosynthetic Efficiency and Productivity in Rice显示文摘Over the past few years, three photorespiratory bypasses have been introduced into plants, two of which led to observable in creases in photos yn thesis and biomass yield. However, most of the experiments were carried out using Arabidopsis under controlled environmental conditions, and the increases were only observed under low-light and short-day conditions. In this study, we designed a new photorespiratory bypass (called GOC bypass), characterized by no reducing equivalents being produced during a complete oxidation of glycolate into CO2 catalyzed by three rice-self-originating enzymes, i.e., glycolate oxidase, oxalate oxidase, and catalase. We successfully established this bypass in rice chloroplasts using a multi-gene assembly and transformation system. Transgenic rice plants carrying GOC bypass (GOC plants) showed significant increases in photosynthesis efficiency, biomass yield, and nitrogen content, as well as several other CO2-enriched phe no types under both greenhouse and field conditions .Grain yield of GOC plants varied depending on seeding season and was increased significantly in the spring. We further demonstrated that GOC plants had significant advantages under high-light conditions and that the improvements in GOC plants resulted primarily from a photosynthetic CO2-concentrating effect rather than from improved energy balance. Taken together, our results reveal that engineering a newly designed chloroplastic photorespiratory bypass could increase photosynthetic efficiency and yield of rice plants grown in field conditions, particularly under high light.Bo-Ran Shen Li-Min Wang Xiu-Ling Lin Zhen Yao Hua-Wei Xu Cheng-Hua Zhu Hai-Yan Teng Li-Li Cui E.-E. Liu Jian-Jun Zhang Zheng-Hui He Xin-Xiang Peng 2019Molecular Plant2019,12,2:30
2The biomass and aboveground net primary productivity of Schima superba-Castanopsis carlesii forests in east China显示文摘The biomass and productivity of Schima superba-Castanopsis carlesii forests in Tiantong,Zhejiang Province,were determined using overlapping quadrants and stem analyses.The total community biomass was(225.3±30.1) t hm-2,of which the aboveground parts accounted for 72.0% and the underground parts accounted for 28.0%.About 87.2% of biomass existed in the tree layer.The resprouting biomass was small,of which over 95.0% occurred in the shrub layer.The productivity of the aboveground parts of the community was(386.8±98.9) g m-2a-1,in which more than 96.0% was present at the tree level.The trunk's contribution to productivity was the greatest,while that of leaves was the smallest.In China,the community biomass of subtropical evergreen broadleaved forests differs significantly with the age of the forest.The community biomass of the 52-year-old S.superba-C.carlesii forests in this study was lower than the average biomass of subtropical evergreen broadleaved forests in China,and was lower than the biomass of other subtropical evergreen broadleaved forests elsewhere in the world.Moreover,its productivity was lower than the model estimate,indicating that without disturbance,this community has great developmental potential in terms of community biomass and productivity.YANG TongHui1,2,SONG Kun1,DA LiangJun1*,LI XiuPeng3 & WU JianPing1 1School of Resources and Environment Science,East China Normal University,Shanghai 200062,China 2Ningbo Academy of Agricultural Science,Ningbo 315040,China 3Ningbo Technology Extension Center for Forestry and Specialty Forest Products,Ningbo 315012,China 2010Science China(Life Sciences)2010,53,7:23
3Study on vegetation ecological water requirement in Ejina Oasis显示文摘The Ecological Water Requirement (EWR) of desert oasis is the amount of water required to maintain a normal growth of vegetation in the special ecosystems. In this study EWR of the Ejina desert oasis is estimated through the relational equation between normalized difference vegetation index (NDVI), productivity and transpiration coefficient, which was established by a combination of the RS, GIS, GPS techniques with the field measurements of productivity. The results show that about 1.53×108 m3 water would be needed to maintain the present state of the Ejina Oasis, and the ecological water requirement would amount to 3.49×108 m3 if the existing vegetation was restored to the highest productivity level at present. Considering the domestic water requirement, river delivery loss, oasis vegetation water con-sumption, farmland water demand, precipitation recharge, etc., the draw-off discharge of the Heihe River (at Longxin Mount) should be 1.93×108―2.23 ×108 m3 to maintain the present state of the Ejina Oasis, and 4.28×108―5.17×108 m3 to make the existing vegetation be restored to the highest productiv-ity level at present.ZHAO WenZhi CHANG XueLi HE ZhiBin ZHANG ZhiHui 2007Science China Earth Sciences2007,50,1:20
4Productivity effect and overuse of pesticide in crop production in China显示文摘Chinese farmers are often accused of overusing pesticides that play a crucial role in enhancing crop yield by reducing losses to crop pests. Pesticide overuse has caused a series of negative health and environmental externalities. This paper quantifies the productivity effect and the optimal amount of pesticides in rice, cotton and maize production in China from the economic perspective. Using survey data collected in 2012 and 2013, both Cobb-Douglas and Weibull damage control specifications are used to estimate the production function. Results show that pesticides have statistically significant productivity effect on crop yield. On the condition of Weibull damage control specifications, the marginal products of 1 kg of the active ingredients of pesticides for rice, cotton and maize are 71.06, 22.73 and 98.45 kg, respectively. However, 57, 64 and 17% of the actual amount of pesticides are overused for rice, cotton and maize, respectively. Moreover, the productivity effect of pesticides would be overestimated using Cobb-Douglas specification without incorporating a damage control agent.ZHANG Chao Guanming Shi SHEN Jian HU Rui-fa 2015Journal of Integrative Agriculture2015,14,9:19
5The impacts of climate extremes on the terrestrial carbon cycle:A review显示文摘The increased frequency of climate extremes in recent years has profoundly affected terrestrial ecosystem functions and the welfare of human society. The carbon cycle is a key process of terrestrial ecosystem changes. Therefore, a better understanding and assessment of the impacts of climate extremes on the terrestrial carbon cycle could provide an important scientific basis to facilitate the mitigation and adaption of our society to climate change. In this paper, we systematically review the impacts of climate extremes(e.g. drought, extreme precipitation, extreme hot and extreme cold) on terrestrial ecosystems and their mechanisms. Existing studies have suggested that drought is one of the most important stressors on the terrestrial carbon sink, and that it can inhibit both ecosystem productivity and respiration. Because ecosystem productivity is usually more sensitive to drought than respiration, drought can significantly reduce the strength of terrestrial ecosystem carbon sinks and even turn them into carbon sources. Large inter-model variations have been found in the simulations of drought-induced changes in the carbon cycle, suggesting the existence of a large gap in current understanding of the mechanisms behind the responses of ecosystem carbon balance to drought, especially for tropical vegetation. The effects of extreme precipitation on the carbon cycle vary across different regions. In general, extreme precipitation enhances carbon accumulation in arid ecosystems, but restrains carbon sequestration in moist ecosystems. However, current knowledge on the indirect effects of extreme precipitation on the carbon cycle through regulating processes such as soil carbon lateral transportation and nutrient loss is still limited. This knowledge gap has caused large uncertainties in assessing the total carbon cycle impact of extreme precipitation. Extreme hot and extreme cold can affect the terrestrial carbon cycle through various ecosystem processes. Note that the severity of such climate extremes depends greatly on their timing, which needs to be investigated thoroughly in future studies. In light of current knowledge and gaps in the understanding of how extreme climates affect the terrestrial carbon cycle, we strongly recommend that future studies should place more attention on the long-term impacts and on the driving mechanisms at different time scales.Studies based on multi-source data, methods and across multiple spatial-temporal scales, are also necessary to better characterize the response of terrestrial ecosystems to climate extremes.Shilong PIAO Xinping ZHANG Anping CHEN Qiang LIU Xu LIAN Xuhui WANG Shushi PENG Xiuchen WU 2019Science China Earth Sciences2019,62,10:16
6中国小麦秸秆纤维潜力研究(英文)显示文摘Based on researches of the crop potential productivity,the potential productivity of light,temperature,water and land from wheat in China were calculated respectively,and converted into the potential productivity of wheat straw according to the coefficient of grain-straw ratio of wheat.Furthermore,based on the wheat planting area in 2006,the potential yield of wheat straw fiber in China was estimated.The results showed that the potential yield of wheat straw fiber in China could reach 94.91 million ton,which could provide evidence for the further potential analysis of bio-ethanol.张敏 杨曼曼 陈伟强 宋安东 2008Agricultural Science & Technology2008,9,5:15
7基于生态过程模型和森林清查数据的森林生长量估算对比研究显示文摘利用遥感驱动的生态过程模型-Boreal Ecosystem Productivity Simulator(BEPS)、2001-2006年国家森林资源连续清查数据(一类清查-样地尺度)和2003-2009年森林资源规划设计调查数据(二类调查-区域尺度),分别计算江西省吉安市的森林生态系统生长量,从不同空间尺度和森林类型对3种数据源估算的森林生长量进行了分析。结果表明,样点尺度上,BEPS模型模拟的森林生长量(4.18 Mg·hm-2·a-1)低于群落生长量(5.86 Mg·hm-2·a-1),与乔木层生长量(4.29 Mg·hm-2·a-1)基本一致,模型模拟结果与两者的拟合R2分别为0.48和0.43。区域尺度上,BEPS模型模拟、二类调查数据计算的群落及乔木层生长量分别为4.65、4.36和3.34 Mg·hm-2·a-1,BEPS模型估算的吉安市各县森林总生长量与二类调查数据计算的群落、乔木层生长总量拟合R2分别达0.84和0.83。一类清查数据计算结果高于二类清查数据计算结果,BEPS模型模拟森林生长量分别与基于一类清查数据计算的乔木层生长量及二类调查数据群落生长量较为一致。从研究区两种主要森林类型来看,常绿阔叶林年平均生长量高于常绿针叶林,常绿针叶林与模型估算结果差异小于常绿阔叶林。最后利用模型估算了研究区2001-2010年平均生长量,为认识研究区的森林生长空间分布差异及更新森林生物量提供支持。李登秋 居为民 郑光 柳艺博 昝梅 张春华 黄金龙 2013生态环境学报2013,22,10:15
8A Model for Estimating Net Primary Productivity of Natural Vegetation显示文摘The net primary productivity (NPP) of vegetation is the net augmentation of green plant material per unit time per unit area on land by photosynthesis (i. e. total production minus autotrophic respiration), which is the base to study the energetic and material transport in ecosystems. Great attention was paid to the research of NPP in recent years, lots of measures were made during the period of the International Biological Programme (IBP). Models based on actual NPP data and on environmental factors朱志辉 1993Chinese Science Bulletin1993,38,22:13
9Longwall automation:trends,challenges and opportunities显示文摘This paper explores the ongoing development and implementation of longwall automation technology to achieve greater levels of underground coal mining performance. The primary driver behind the research and development effort is to increase the safety, productivity and efficiency of longwall mining operations to enhance the underlying mining business. A brief review of major longwall automation challenges is given followed by a review of the insights and benefits associated with the LASC longwall shearer automation solution. Areas of technical challenge in sensing, decision support, autonomy and human interaction are then highlighted, with specific attention given to remote operating centres, proximity detection and systems-level architectures in order to motivate further automation system development.The vision for a fully integrated coal mining ecosystem is discussed with the goal of delivering a highperformance, zero-exposure and environmentally coherent mining operations.Jonathon C.Ralston Chad O.Hargrave Mark T.Dunn 2017International Journal of Mining Science and Technology2017,27,5:11
10Paleoproductivity records for the past 30 ka in the southern Nansha area, the South China Sea显示文摘This note presents productivity variations for the past 30 ka in the southern Nansha area, the South China Sea, from the gravity core 17962 (7°11 ′N, 112°5′E, core length: 8 m, water depth: 1 968 m). Estimated surface productivity demonstrates that at the last glacial maximum the productivity was about 1.6 times as much as that in the Holocene, and the change may be ascribed to an increase of terrestrial nutrients as sea level lowered in the glacial time.Dianyong Fang Zhimin Jian Pinxian Wang 2000Chinese Science Bulletin2000,45,13:10
11Monitoring the impact of climate change and human activities on grassland vegetation dynamics in the northeastern Qinghai-Tibet Plateau of China during 2000–2015显示文摘Climate change and human activities can influence vegetation net primary productivity(NPP), a key component of natural ecosystems. The Qinghai-Tibet Plateau of China, in spite of its significant natural and cultural values, is one of the most susceptible regions to climate change and human disturbances in the world. To assess the impact of climate change and human activities on vegetation dynamics in the grassland ecosystems of the northeastern Qinghai-Tibet Plateau, we applied a time-series trend analysis to normalized difference vegetation index(NDVI) datasets from 2000 to 2015 and compared these spatiotemporal variations with trends in climatic variables over the same time period. The constrained ordination approach(redundancy analysis) was used to determine which climatic variables or human-related factors mostly influenced the variation of NDVI. Furthermore, in order to determine whether current conservation measures and programs are effective in ecological protection and reconstruction, we divided the northeastern Qinghai-Tibet Plateau into two parts: the Three-River Headwater conservation area(TRH zone) in the south and the non-conservation area(NTRH zone) in the north. The results indicated an overall(73.32%) increasing trend of vegetation NPP in grasslands throughout the study area. During the period 2000–2015, NDVI in the TRH and NTRH zones increased at the rates of 0.0015/a and 0.0020/a, respectively. Specifically, precipitation accounted for 9.2% of the total variation in NDVI, while temperature accounted for 13.4%. In addition, variation in vegetation NPP of grasslands responded not only to long-and short-term changes in climate, as conceptualized in non-equilibrium theory, but also to the impact of human activities and their associated perturbations. The redundancy analysis successfully separated the relative contributions of climate change and human activities, of which village population and agricultural gross domestic product were the two most important contributors to the NDVI changes, explaining 17.8% and 17.1% of the total variation of NDVI(with the total contribution >30.0%), respectively. The total contribution percentages of climate change and human activities to the NDVI variation were 27.5% and 34.9%, respectively, in the northeastern Qinghai-Tibet Plateau. Finally, our study shows that the grassland restoration in the study area was enhanced by protection measures and programs in the TRH zone, which explained 7.6% of the total variation in NDVI.XIONG Qinli XIAO Yang Marwa Waseem A HALMY Mohammed A DAKHIL LIANG Pinghan LIU Chenggang ZHANG Lin Bikram PANDEY PAN Kaiwen Sameh B EL KAFRAWAY CHEN Jun 2019Journal of Arid Land2019,11,5:10
12Erosion effect on the productivity of black soil in Northeast China显示文摘Continuous soil erosion has caused serious land degradation in the black soil area of Northeast China. The primary objective of this study was to determine the effects of accelerated erosion on soil productivity, as measured by soybean (Glycine max L. Merr.) yields. Eight erosion levels, 0, 10, 20, 30, 40, 50, 60, and 70 cm, were simulated by imitating the integrated process of natural erosion and tillage activity. Each erosion level had two sub-treatments: conventional fertilization and no fertilization. Soil erosion was found to affect survival probability and to cause remarkable reductions in the Leaf Area Index (LAI), plant height, pod number, biomass, and yield. Soybean yield was exponentially decreased with the increase of soil erosion depth. Compared to erosion depth of 0 cm, erosion levels of 10, 20, 30, 40, 50, 60, and 70 cm experienced reductions in soybean yield by 28.8%, 37.8%, 43.5%, 52.6%, 53.1%, 52.9%, and 64.1% respectively when fertilized whereas the reductions at those levels were 32.6%, 42.2%, 53.0%, 54.0%, 65.8%, 69.7%, and 72.6%, respectively, when unfertilized. At the erosion depths of 10, 20, 30, 40, 50, 60, and 70 cm, the yield reductions per 10 cm of soil eroded when fertilized were 28.8%, 18.9%, 14.5%, 13.2%, 10.6%, 8.8%, and 9.2%, averaged 14.9%, but when unfertilized they were 32.6%, 21.1%, 17.7%, 13.5%, 13.2%, 11.6%, and 10.4%, averaged 17.1%. The results also showed that chemical fertili zers could enhance the yields of eroded soil, but could not recover the yields to the pre-erosion level. Additionally, the results indicated that the primary reason for the decrease in soybean yield with increasing erosion depth was the loss of soil organic matter, soil N and P. These results may aid in selecting effective soil erosion control strategy, forecasting land degradation, establishing soil erosion tolerance, and evaluating the economic cost of soil erosion in the black soil region in Northeast China.WANG ZhiQiang LIU BaoYuan WANG XuYan GAO XiaoFei LIU Gang 2009Science China Earth Sciences2009,52,7:9
13Quaternary biogenic opal records in the South China Sea: Linkages to East Asian monsoon, global ice volume and orbital forcing显示文摘Particulate fluxes investigated in the central South China Sea (SCS) during 1993―1996 indicate that opal flux can be used to show primary productivity change, which provides a foundation for tracing the evolutionary relationship between the surface productivity and East Asian monsoon in the SCS during the late Quaternary glacial and interglacial periods. Based on the studies of opal % and their mass accumulation rates (MAR) at the six sites recovered from the SCS during the “Resolution” ODP Leg 184 and “Sonne” 95 cruise of the Sino-Germany cooperation, opal % and their MARs increased evidently in the northern sites since 470―900 ka, and they enhanced and reduced, respectively, during the glacial and interglacial periods. Whereas they increased obviously in the southern sites since 420―450 ka, and they augmented and declined, respectively, during the interglacial and glacial periods. The vari- ability in opal % and their MARs in the late Quaternary glacial cyclicity indicate the “seesaw” pattern of surface productivity in the SCS. The winter monsoon intensified during the glacial periods, surface productivity increased and decreased, respectively, in the northern and southern SCS. The summer monsoon strengthened during the interglacial periods, surface productivity increased and decreased, respectively, in the southern and northern SCS. The cross spectral analyses between the opal % in the northern and southern SCS during the Quaternary and global ice volume (δ 18O) and orbital forcing (ETP) indicate that the East Asian winter and summer monsoons could be ascribed to the different drive mechanisms. On the orbital time scale, the global ice volume change could be a dominant factor for the winter monsoon intension and temporal variations. As compared with the winter monsoon, the correlative summer solar radiation with the obliquity and precession in the Northern Hemisphere could be a mostly controlling factor for the summer monsoon intension and temporal variations.WANG RuJian JIAN ZhiMin XIAO WenShen TIAN Jun LI JianRu CHEN RongHua ZHENG YuLong CHEN JianFang 2007Science China Earth Sciences2007,50,5:9
14Variations of opal accumulation rates and paleoproductivity over the past 12 Ma at ODP Site 1143, southern South China Sea显示文摘The biogenic silica analysis was performed on 463 samples from ODP 184 Site 1143, the southern South China Sea. The results show that the opal content and MAR evidently increased between 12.3 and 5.7 Ma, which was contemporary with the high carbonate and total MARs, reflecting the high biogenic productivity in the late Miocene. This demonstrates the occurrence of the late Miocene 'Biogenic Bloom Event' in the southern South China Sea, corresponding to the late Miocene-early Pliocene 'Biogenic Bloom Event' in the Indian-Pacific Ocean. The increases of opal content and MAR after the middle Pleistocene (about 0.7 Ma) is inferred to result from the enhanced upwelling and nutrient supply, which was induced by the intensified monsoon circulation after the 'Mid-Pleistocene Revolution'.Li Jianru Wang Rujian Li Baohua 2002Chinese Science Bulletin2002,47,7:8
15Spatio-temporal patterns of forest carbon dioxide exchange based on global eddy covariance measurements显示文摘Spatio-temporal patterns and driving mechanisms of forest carbon dioxide (CO2) exchange are the key issues on terrestrial ecosystem carbon cycles, which are the basis for developing and validating ecosystem carbon cycle models, assessing and predicting the role of forests in global carbon balance. Eddy covariance (EC) technique, an important method for measuring energy and material exchanges between terrestrial ecosystems and the atmosphere, has made a great contribution to understanding CO2 exchanges in the biosphere during the past decade. Here, we synthesized published EC flux measurements at various forest sites in the global network of eddy flux tower sites (FLUXNET) and regional flux networks. Our objective was to explore spatio-temporal patterns and driving factors on forest carbon fluxes, i.e. net ecosystem productivity (NEP), gross primary productivity (GPP) and total ecosystem respiration (TER). Globally, forest NEP exhibited a significant latitudinal pattern jointly controlled by GPP and TER. The NEP decreased in an order of warm temperate forest > cold temperate and tropical rain forests > boreal and subalpine forests. Mean annual temperature (MAT) made a greater contribution to forest carbon fluxes than sum of annual precipitation (SAP). As MAT increased, the GPP increased linearly, whereas the TER increased exponentially, resulting in the NEP decreasing beyond an MAT threshold of 20°C. The GPP, TER and NEP varied substantially when the SAP was less than 1500 mm, but tended to increase with increasing SAP. Temporal dynamics in forest carbon fluxes and determinants depended upon time scales. NEP showed a significant interannual variability mainly driven by climate fluctuations and different responses of the GPP and TER to environmental forcing. In a longer term, forest carbon fluxes had a significant age effect. The ecosystem was a net carbon source right after clearcutting, gradually switched to a net carbon sink when the relative stand age (i.e. ratio of actual stand age to the stand rotation age) approached 0.3, and maximized carbon sequestration capacity at premature or mature stand stages. This temporal pattern of NEP was correlated with stand leaf area index and associated GPP. This study highlights the significance of spatio-temporal dynamics in the CO2 exchange in forest carbon cycling studies. It is also suggested that in addition to forest biomes, interannual variations and stand age effects of forest carbon fluxes should be considered in the global carbon balance.XingChang Wang ChuanKuan Wang GuiRui Yu 2008Science China Earth Sciences2008,51,8:8
16Development of Chinese characterization factors for land use in life cycle impact assessment显示文摘A model with Chinese characterization factors for quantifying the damages to environment by land use in terms of the change in net primary productivity (NPP) of ecosystem was developed in the framework of life cycle assessment (LCA).In this method,the forms of land utilization were divided into two aspects involving long-term use of land (e.g.,for arable farming),namely 'land occupation',and the change of land properties (e.g.,from agricultural area to urban area),namely 'land transformation'.Furthermore,the land use elementary flows (occupation and transformation) and parameters were linked to the impact indicators,and the characterization formulas of the two forms of land utilization were derived respectively according to the ecological theory.Moreover,based on this method,the characterization factors of both land occupation and land transformation were calculated using Chinese empirical information on NPP,which can be incorporated into LCA framework and applied to Chinese LCA case study to fill up the important gap in life cycle impact assessment (LCIA) of land use.LIU Yu,NIE ZuoRen,SUN BoXue,WANG ZhiHong & GONG XianZheng School of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China 2010Science China(Technological Sciences)2010,53,6:8
17Maize response to elevated plant density combined with lowered N-fertilizer rate is genotype-dependent显示文摘Increasing plant density and improving N fertilizer rate along with the use of high density-tolerant genotypes would lead to maximizing maize(Zea mays L.) grain productivity per unit land area. The objective of this investigation was to match the functions of optimum plant density and adequate nitrogen fertilizer application to produce the highest possible yields per unit area with the greatest maize genotype efficiency. Six maize inbred lines differing in tolerance to low N and high density(D) [three tolerant(T); L-17, L-18, L-53,and three sensitive(S); L-29, L-54, L-55] were chosen for diallel crosses. Parents and crosses were evaluated in the 2012 and 2013 seasons under three plant densities: low(47,600),medium(71,400), and high(95,200) plants ha-1and three N fertilization rates: low(no N addition), medium(285 kg N ha-1) and high(570 kg N ha-1). The T × T crosses were superior to the S × S and T × S crosses under the low N–high D environment in most studied traits across seasons. The relationships between the nine environments and grain yield per hectare(GYPH) showed near-linear regression functions for inbreds L54, L29, and L55 and hybrids L18 × L53 and L18 × L55 with the highest GYPH at a density of47,600 plants ha-1and N rate of 570 kg N ha-1and a curvilinear relationship for inbreds L17, L18, and L53 and the rest of the hybrids with the highest GYPH at a density of95,200 plants ha-1combined with an N rate of 570 kg N ha-1. Cross L17 × L54 gave the highest grain yield in this study under both high N–high-D(19.9 t ha-1) and medium N–high-D environments(17.6 t ha-1).Ahmed Medhat M.Al-Naggar Reda A.Shabana Mohamed M.M.Atta Tarek H.Al-Khalil 2015The Crop Journal2015,3,2:7
18Radiolarian transfer function for paleo-primary productivity in the South China Sea显示文摘Basic data of radiolarian group and primary productivity were from 46 investigation stations of the South China Sea. The factor analysis of principal component and the least squares estimation in both linear regression and nonlinear estimation were applied to establishing the radiolarian transfer function for paleo-primary productivity in this sea area. The results show that the transfer function of nonlinear regression analysis for the radiolarian assemblage and primary productivity has much better parameters. Factors analysis has accumulating variance of 83.6% and communalities of more than 0.940347. Nonlinear regression analysis gives multiple correlation coefficient as 0.84888 and explained variance as 72.059%. The equation of transfer function is with an average estimated error of about 53.778 mg·C/m^2·d, which is 14.69% in average observed values. Calculation accuracy is 85.31% for the system of transfer function.Muhong Chen Liangmin Huang Xia Tu Fan Zheng 1999Chinese Science Bulletin1999,44,13:6
19Biomass, productivity and energy use efficiency of climax vegetation on Dinghu Mountains, Guangdong, China显示文摘The biomass, primary productivity and energy use efficiency of photosysthetically active radiation of climax vegetation on Dinghu Mountains, in low subtropical were studied with the tree-harvested, litter gather, CO, analysis methods, etc. The results show that the leaf area index of the community is 17; biomass, 363 t·(hm2) -1 · a-1, total productivity, 132 t· (hm2) -1 · a-1; primary productivity, 23.2 t · (hm2) -1· a-1; litter-fall, 9.2t ·(hm2)-1·a-1; death tree, 3.9 t·(hm2)-1· a-1, animal-eating, 0.6 t·(hm2) -1 · a-1; net productivity, 9.5 t·(hm2)-1· a-1.彭少麟 张祝平 1995Science China Chemistry1995,38,1:6
20Productivity and nutrient cycling in an agroforestry ecosystem for interplant of pineapple and coconut显示文摘in this paper, the biomass productivity and nutrient cycling in an agroforestry system of coconut (Cocus nucifera ) interplanted with pineapple bananas comosus) had been studied. The result showed that the biomass productivity of this ecosystem was 47 460 kg.hm-2.a-1, which was 4.3 times as much as that of pure coconutplantation. In the biological cycling of N. P, K elements, the total annual retention was 559.470 kg.hm-2, the annualreturn was 410.745 kg.hm-2, the annual uptake was 970.475 kg.hm-2, respectively. The average circulation rate inthree nutrient elementS (N, P, K) was 42.32%, which was 27.53% more than that in pure coconut stands. Coconutinterplanted with pineapple was proved to be one of optimum cultUral patterns, which had the higher biomass productivity, and better usage efficiency of environment resources in tropical areas.彭方仁 黄宝龙 1999Journal of Forestry Research1999,10,3:5
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