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ENERGY DISTRIBUTION AND BIOLOGICAL productivity IN KOREAN PINE PLANTATION

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Journal of Northeast Forestry University 1994年第2期5卷 46-53页

作者：张彦东 Northeast Forestry University China

This investigation was carried out with the 28-year-old korean Pine plantation in Maoershan Area of Heilonaiiang Province. The paper revealed the character of energy distribution in korean Pine plantation. The total solar radiations reaching the canopy were discussed respectively and the change pattern of radiation in the forest were analyzed in detail. The solar radiation received by canopy counts up to 2580. 64 MJ/m2in growth season, of which. direct solar radiation is 1508. 52 MJ/m2 and scattered radiation 1072. 12 MJ/m’. The radiation energy reaching the forest land surface thronghthe canoPy is 277. 25MJ/m2, with a transmissivity of about 10. 74%- The net production formed by photosynthesis of forest is 16. 89 MJ/m2 and the net radiation reception by the ecosystem comes to 1091. 88 MJ/m2 during growth seasons, therefore the utilisation effciency of solar radiation energy derived ffom the net radiation taken as basis is 1. 55% in the korean pine plantation.

关键词： Korean pine Plantation Energy transfer Biological productivity

THE PRIMITIVE STUDY ON THE RELATIONSHIP BETWEEN ARTIFICIAL SCOTCH PINE productivity AND ITS DENSITY IN WESTERN PART OF HEILONGJIANG

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Journal of Northeast Forestry University 1994年第4期5卷 6-12页

作者：苑增武李桂生宋国育 Forest Protection Institute of Heilongjiang Province China Northeast Forestry University China

According to the data of wood analysis and biomass invcstigation, wc analyse the relationship among scotch pine stock, the growth of volume and its density, thc relationship between bio-productivity and its density as well as the law of the distribution of biomass of various organs of the scotch pine. The conclusions showcd that the stock, volume, growth, bio produetivity and its density were interrclated closely. The appropriate density was 620--820 individuls / hm2 of mid-aged trees. The distributions of biomass on various organs werc different at different age stage. This paper gave the evidence to value artificial scotch pine, its structures and functions.

关键词： Scotch pine productivity Density

Dynamic evaluation of land productivity in China

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Chinese Journal of Population,Resources and Environment 2013年第3期11卷 253-260页

作者： Rui Yu Xiangzheng Deng Zhe Yan Chenchen Shi Faculty of Resources and Environmental Science Hubei University Center for Chinese Agricultural Policy Chinese Academy of Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University

For making rational and scientific land-use planning,an inventory indicator of land productivity subject to biophysical limitations and human disturbance is required.This study introduces agricultural land productivity(ALP)as the dynamic indicator to measure land productivity,involving factors that affect agricultural production,such as characteristics of climate,soil,and terrain.As a case study of this dynamic indicator,ALP was estimated at county level and aggregated into provincial level in the whole of China.The result shows that ALP increased during 2000-2010 in China,and the ratios of ALP to the actual grain yield were 65.40%and 66.38%in the years 2000 and 2005,respectively.The ALP is an effective dynamic indicator to estimate the land productivity and to represent the basic conditions about the supply of water,energy,nutrients,and the physical basis for plant growth,as well as the local input.ALP estimation could provide supporting information for policy-making about land production planning and land-use management.

关键词： land productivity ALP grain yield crop production land resources

A Model for Estimating Net Primary productivity of Natural Vegetation

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Chinese Science Bulletin 1993年第22期38卷 1913-1917页

作者：朱志辉 Institute of Geography Academia Sinica Beijing 100101 PRC

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

关键词： natural vegetation primary productivity model

A NEW METHOD FOR INCREASING THE productivity OF LARCH PLANTATION

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Journal of Northeast Forestry University 1994年第2期5卷 9-12页

作者：陈祥伟丁宝永赵春梅 Northeast Forestry University China

A new method for increasing the productivity of larch plantation was pointed out by applying the edge effect in production in this paper. For the radiation of sunlight is identical in the same unit area of the same latitude, we could not increase the productivity by changing the total radiation, but we can change the property of the floor by setting up effect be1ts and develop the structure of community and the photosynthetic system. In the end, significant benefits on productivity and biological, ecological effects were showed by 30 years experiments.

关键词： Edge effect Community structure Property of the floor productivity

THE FACTORS AFFECTING THE productivity OF HORIZONTAL WELLS

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石油勘探与开发 1994年第5期 105-115页

作者： Hu Dong-hui Yan Jie-nian(Petroleum University,Donying 257062, P.R. China)(Checked by Qin Tong-luo)

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关键词： Horizontal well Production index productivity Formation damage

The Concept of Agricultural productivity on Ecosystem Scale and Its Measurement

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Agricultural Sciences in China 2006年第9期5卷 707-712页

作者： ZHU Wan-bin QIU Hua-jiao CHANG Xin CHENG Xu College of Resources and Environment China Agricultural University Beijing 100094 P.R.China College of Agronomy and Biotechnology China Agricultural University Beijing 100094 P.R.China

What is the connotation and the extension of the productivity concept and how to calculate it are the core problems in evaluating an agricultural-production process. The attributes of agricultural production processes have changed greatly in the last 100 years, and the methods to describe and measure the productivity failed to keep in pace with the production processes, resulting in a totally vague, incomplete evaluation of the production processes. Sometimes the serious problem of pollution is ignored in the race to shortdated money making, thus leading to a blooming and flooding pollution; sometimes the great ecological benefits are ignored and the corresponding production processes suffer drastically from “economic deficit”. With the old agricultural productivity indices, no prediction can be made of the ultimate effects of agroecosytem on mankind-pollution or welfare. A new concept, agricultural productivity on ecosystem scale （APES） and the related indices are defined here to solve these problems. Emergy and exergy are introduced to help the measurement of the indices. Emergy is the memory of energy, which can be used to measure the total cost, including natural capital and social capital. APES of the agroecosystem is the aggregated contributions of all components to mankind and its habitat in uniformed dimensions, it may be expressed in material, energy, information, organization, pollution and damage, etc., positive or negative, and are calculated based on exergy methods. And a related index agroecological coupling degree （ACD） shows sustainability.

关键词： agroecosystem productivity emergy exergy

Biodiversity, productivity, and temporal stability in a natural grassland ecosystem of China

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Research in Cold and Arid Regions 2018年第4期10卷 293-304页

作者： Bing Liu WenZhi Zhao YangYang Meng Chan Liu Linze Inland River Basin Research Station Key Laboratory of Ecohydrology of Inland River Basin Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences

Understanding the effect of biodiversity on ecosystem function is critical to promoting the sustainability of ecosystems and species conservation in natural ecosystems. We observed species composition, species richness and aboveground biomass,and simulated the competitive assemblages in a natural grassland ecosystem of China, aiming to test some assumptions and predictions about biodiversity–stability relationships. Our results show that aboveground productivity and temporal stability increased significantly with increasing species richness, and via a combination of overyielding, species asynchrony, and portfolio effects. Species interactions resulted in overyielding caused by trait-independent complementarity, and were not offset by a negative dominance effect and trait-dependent complementarity effect. Therefore, the mechanisms underlying the biodiversity effect shifted from the selection effect to the complementarity effect as diversity increased, and both effects were coexisted but the complementarity effect represent a mechanism that facilitates long term species coexistence in a natural grassland ecosystem of China.

关键词： biodiversity productivity temporal stability overyielding effect species interactions complementarity effect selection effect

Measuring Quality of Economic Growth Incorporating Environment and Social Welfare:a Total productivity Approach with an Application on China

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Journal of Donghua University(English Edition) 2018年第5期35卷 411-417页

作者：孙燕燕 RAHMAN Sanzidur DAI Changjun Shanghai Institute of Tourism Shanghai Normal University School of Geography Earth and Environmental SciencesUniversity of Plymouth Glorious Sun School of Business &Management Donghua University

By extending the traditional productivity theory,a new concept total productivity( TP) is introduced. Using a directional distance function approach,the concept is applied to measuring economic growth of 8 economic regions of China covering an 18 years period( 1997—2014) and test its convergence. Results showed that TP grew at an average rate of 6. 6% per year led mainly by technical change( 6. 5%). When environmental undesirable outputs are included,the Middle Yellow River,Northwest and Southwest regions of China witnessed higher productivity changes. Results of the convergence analysis revealed that China had made progress in reducing regional imbalance in growth. Inclusion of undesirable output showed that the energy-saving emission reduction policies had speed up the convergence rate of TP and environment oriented productivity. However,China's welfare oriented productivity is still very low.

关键词： undesirable output directional distance function total productivity(TP) Malmquist-Luenberger productivity index quality of economic growth