In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenan...In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenance of biodiversity in Meizhou by the methods of market price,shadow prices approach and opportunity cost,and the problems of the value assessment at home and abroad in urban forest ecosystem services function were simply discussed.展开更多
Fire is an important ecological factor and what constitutes appropriate fire management is much debated in the US and elsewhere. The role of fire as a source of greenhouse gases has been intensively investigated, but ...Fire is an important ecological factor and what constitutes appropriate fire management is much debated in the US and elsewhere. The role of fire as a source of greenhouse gases has been intensively investigated, but less is known about the production rate of the solid black carbon residue from fires. Black carbon accumulates in soil as it has longer turnover times than plant residues. To understand the significance of black carbon production during wildfire, we quantified black carbon using hydropyrolysis in O and A horizons before and after a prescribed bum at four sites in the New Jersey Pine Barrens forest in the North-Eastern US. Black carbon was found in both O- and A-horizons at all investigated sites, stocks in the range of 61.31-168.15 g m^-2 in the O-horizon and 169.59-425.25 g m^-2 in the A-horizon. Total black carbon stocks did not increase following the fire suggesting that either black carbon production in fires may be small compared to the variability, or that equivalent amounts of black carbon formed in previous fires may have been consumed in the fire. The study raises questions about how black carbon production and consumption in ftres can be quantified separately.展开更多
This paper reveals the variations of S concentration among the leaf surface and other organs of variousplant species, and presents the distribution natures of S storage in the evergreen broad-leaved forest vege-tation...This paper reveals the variations of S concentration among the leaf surface and other organs of variousplant species, and presents the distribution natures of S storage in the evergreen broad-leaved forest vege-tation in Hangzhou on the basis of the tested data concerning plant S contents. The result was that theS concentrations on the tree leaf surfaces varied with the testing time and plant species. The range of Scontents in various organs of a plant was 2.086- 4.245 S g kg￣(-1), varying with plant species in this forest.The S content in the leaves was the highest, followed by that in the branches, trunks and roots, which showedthat there was an apical dominance of S distribution. The total amount of S storage in the vegetation wasas large as 349.97 S kg ha￣(-1). The S distribution in this vegetation had two characteristics as follows: 1)for the vegetation layers, arbor layer > renewal layer > herb layer > shrub layer; and 2) for the verticaldistribution per unit height (m), root stratum (0 - 0.20 m of soil depth)> stratum nearby the ground surface(0 - 0.5m) > canopy (4.0- 9.5m) > trunk stratum (2.0- 4.0m).展开更多
The work was carried out to study the uptake, storage and return of S in the evergreen broad-leaved forestecosystem of Hangzhou in Zhejiang Province, China, based on the annual increments of plants and S contentsper u...The work was carried out to study the uptake, storage and return of S in the evergreen broad-leaved forestecosystem of Hangzhou in Zhejiang Province, China, based on the annual increments of plants and S contentsper unit weight plant organs as well as the measured data about the biological return and decomposition.Results showed that the vegetation layer had an annual S uptake of 55.02kg ha￣(-1) , which accounted for 15.8% of the total S storage in the vegetation layer. The S uptake was the highest in the arbor layer but thelowest in the shrub layer. The biological return of S was 50% higher than the biological uptake, indicatingthe relatively high cycling efficiency of S. Nevertheless, S had a relatively low rate of biological release, so thatS trended to accumulate in the litter layer. S taken up by plants each year came mostly from precipitationand the reserve of soil.展开更多
基金Supported by Special Funds for Central Financial to Support the Local Colleges and Universities([2013]389)~~
文摘In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenance of biodiversity in Meizhou by the methods of market price,shadow prices approach and opportunity cost,and the problems of the value assessment at home and abroad in urban forest ecosystem services function were simply discussed.
文摘Fire is an important ecological factor and what constitutes appropriate fire management is much debated in the US and elsewhere. The role of fire as a source of greenhouse gases has been intensively investigated, but less is known about the production rate of the solid black carbon residue from fires. Black carbon accumulates in soil as it has longer turnover times than plant residues. To understand the significance of black carbon production during wildfire, we quantified black carbon using hydropyrolysis in O and A horizons before and after a prescribed bum at four sites in the New Jersey Pine Barrens forest in the North-Eastern US. Black carbon was found in both O- and A-horizons at all investigated sites, stocks in the range of 61.31-168.15 g m^-2 in the O-horizon and 169.59-425.25 g m^-2 in the A-horizon. Total black carbon stocks did not increase following the fire suggesting that either black carbon production in fires may be small compared to the variability, or that equivalent amounts of black carbon formed in previous fires may have been consumed in the fire. The study raises questions about how black carbon production and consumption in ftres can be quantified separately.
文摘This paper reveals the variations of S concentration among the leaf surface and other organs of variousplant species, and presents the distribution natures of S storage in the evergreen broad-leaved forest vege-tation in Hangzhou on the basis of the tested data concerning plant S contents. The result was that theS concentrations on the tree leaf surfaces varied with the testing time and plant species. The range of Scontents in various organs of a plant was 2.086- 4.245 S g kg￣(-1), varying with plant species in this forest.The S content in the leaves was the highest, followed by that in the branches, trunks and roots, which showedthat there was an apical dominance of S distribution. The total amount of S storage in the vegetation wasas large as 349.97 S kg ha￣(-1). The S distribution in this vegetation had two characteristics as follows: 1)for the vegetation layers, arbor layer > renewal layer > herb layer > shrub layer; and 2) for the verticaldistribution per unit height (m), root stratum (0 - 0.20 m of soil depth)> stratum nearby the ground surface(0 - 0.5m) > canopy (4.0- 9.5m) > trunk stratum (2.0- 4.0m).
文摘The work was carried out to study the uptake, storage and return of S in the evergreen broad-leaved forestecosystem of Hangzhou in Zhejiang Province, China, based on the annual increments of plants and S contentsper unit weight plant organs as well as the measured data about the biological return and decomposition.Results showed that the vegetation layer had an annual S uptake of 55.02kg ha￣(-1) , which accounted for 15.8% of the total S storage in the vegetation layer. The S uptake was the highest in the arbor layer but thelowest in the shrub layer. The biological return of S was 50% higher than the biological uptake, indicatingthe relatively high cycling efficiency of S. Nevertheless, S had a relatively low rate of biological release, so thatS trended to accumulate in the litter layer. S taken up by plants each year came mostly from precipitationand the reserve of soil.
