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氮素是植物生长发育所需的大量元素之一,水稻是我国的主要粮食作物,水稻生产对氮的需求仅次于水,是构成水稻生长成本的主要部分。目前,水稻氮肥表观利用率只有39%,即施氮肥量的50%以上残留在环境中。因此,在保证产量不减的基础上如何提高氮肥的利用效率,减少氮肥的使用量是我国农业可持续发展亟待解决的重要问题。
In order to monitor the change of regional ecological environment quality, this paper use MODIS and DMSP / OLS remote sensing data, from the production capacity, external disturbance changes and human...
The area of forest destruction as well as the annual growth loss due to road construction before constructing a road was predicted. To do this, road cross sections of 88 points along the 10 km propose...
From an economic point of view a well-designed road path with the minimum construction cost is an optimal path that can be found using Dijkstra’s algorithm. In this study Dijkstra’s algorithm that con...
The construction of the Římov Reservoir on the Malše River in 1978 significantly influenced the fish assemblage within the river, above the reservoir. Fish species that had successfully colo...
This research deals with productivity and cost of rock disintegration and side casting of materials with the use of a hydraulic hammer mounted on a PC 220 Komatsu crawler excavator, which is used on r...
The paper summarizes results of an institutional research aimed at assessing the bending strength and modulus of elasticity in bending of exterior foiled combined and all-beech plywoods in relation to...
Many studies on methane (CH4) and nitrous oxide (N2O) emissions from livestock industries have revealed that livestock production directly contributes to greenhouse gas (GHG) emissions through enteric...
Bamboo is widely recognized as one of the most important non-timber forest resources because of the high socio-economic benefits from bamboo based products. It is estimated that there are over 1200 sp...
We examined the relationship between dwarf-bamboo growth and small rodents on Mt. Ohdaigahara where the population density of sika deer (Cervus nippon) has been increasing and trunk debarking by the d...
In this paper we constructed a volume table for broad-leaved trees including a stem and branches using a relative stem curve, provided that the trees are subject to the pipe model theory. First we mea...
The Forestry Department of the Ise Shrine is planning to produce timbers in the Ise Shrine Forest to rebuild the temples for the Shikinen Sengu Ceremony held every 20 years. Thus, this study proposes ...
A control diagram of crown and stem form was attempted to construct based on the analysis of relationships among several stand characteristics. The data was collected from 32 young even-aged stands of...
Construction of tea production system in conformity with the standardization of nitrate nitrogen concentration in the environment.
An online web service system for a pedigree analysis was constructed. In this service, coefficients of parentage, inbreeding coefficients, numbers of ancestors in the pedigree, etc., are calculated ...

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