高木森关于中国绘画思想史中的分期问题研究

高木森是海外研究中国绘画思想史方面卓有成效的学者,本文通过对其系列学术思想与著作进行研读,对在中西文化思想激烈碰撞与绘画史观转型历史语境中的分期问题进行研究,探讨其对中国绘画思想史分期的内容、理论依据与学术贡献。

Integrated Analysis of the Trees and Associated UnderCanopy Species in a Subalpine Forest of Western Himalaya,Uttarakhand, India

Subalpine forests are known as outstanding habitats due to co-existence of both temperate and alpine vegetation and are classic example of ecotonal zones. Limited but diverse physiognomy of trees inhabiting in subalpine forest results in variability within under-canopy habitat conditions. Studies were undertaken to assess population status, habitat preference and interferences to the trees and associated under-canopy herbs in a subalpine forest of western Himalaya. A total of lo woody and 23 under-canopy herbs were recorded in the selected subalpine forest area. At each stand, the number of tree species and under-canopy herbs ranged from 2 to 4 and 8 to lo respectively. Abies spectabilis, Acer caesium, Quercus floribunda, Q. semecarpifolia and Rhododendron arboreum were key tree species in this area. The density of main woody species was 280 to 119o individuals ha-1 at different stands. Herbaceous plants with rosette and clump growth habits were observed to have higher values for total basal cover and importance value index. Presence of some under- canopy herbs like; Dactylorhiza hatagirea, Malaxis muscifera, Picrorhiza kurrooa, Polygonatum cirrhifolium habitats also and Skimmia laureola showed that they are in the habitat specific specific. However, the presence of Frageria nubicola and Viola sp. was common in the selected stands. Felling of trees for timber, construction of temporary huts, fuel wood and lopping for fodder were main interferences for trees. On the other hand, trampling driven damage due to grazing, habitats degradation and overexploitation were observed key threats for under-canopy herbs. Integrated analysis including population studies, habitats preference and interferences to the trees and under-canopy herbs in this sensitive and important ecosystem will be useful for determining the conservation plans and ecosystem management.

Spatial patterns and storage composition of woody debris in a natural secondary forest dominated by Pinus tabulaeformis on Loess Plateau, China

Woody debris(WD) is an important par of natural Pinus tabulaeformis mixed stands, and i affects the forest ecosystem stability and developmen The WD spatial patterns are especially importan structural characteristics that can provide insights into forest dynamics. In this paper, the WD storage WD spatial patterns and WD associations among the main species were examined in the natural secondary forest on Loess Plateau in northwest China. Data were collected in a 1 ha(100 m × 100 m) permanent plot and all the trees with a diameter at breast height o more than 3 cm were measured and stem-mapped Ripley's K functions from the spatial-point-pattern analysis method were used to analyze the spatia distribution and associations. The results showed tha(1) The total storage of WD was 10.73 t/ha, fallen wood was the main source of WD, and the majority diameters were greater than 20 cm, and in intermediate levels of decay;(2) The overall spatia pattern was closely related to the spatial scale, which exhibited an aggregated pattern on a small scale, and a random pattern on a large scale. The spatia patterns of coarse woody debris also gradually transitioned from an aggregated pattern in fine scales to a random pattern in broader spatial scales, which matched the overall spatial pattern. The spatial intensity was gradually decreased with the increasing diameters, and increased with the decomposition classes;(3) The WD of Pinus tabulaeformis species was negatively associated with Betula platyphylla and Populus davidiana on a small scale but positively associated with these species on a large scale. The spatial pattern and interspecies relations were the results of long-term interactions between the natural secondary forest community and the surrounding natural environment. These findings would provide a scientific basis for the sustainable management and protection of natural secondary forest ecosystems on Loess Plateau.

Changes in carbon,nitrogen and phosphorus stoichiometry in decaying logs with gap positions in a subalpine forest

Aims The redistribution of forest gaps based on solar radiation and precipitation(mainly rainfall and snowfall)can create heterogenous microenvironments inside and outside the gaps.Here,we investigated the effects of forest gaps on carbon(C),nitrogen(N)and phosphorus(P)stoichiometry in decaying logs by altering the microenvironments.Methods Minjiang fir(Abies faxoniana)logs of decay classes I–V were incubated in situ on the floor under the gap center(GC),gap edge(GE)and closed canopy(CC)in a subalpine forest in the eastern Qinghai-Tibet Plateau.The C,N and P concentrations in decaying bark,sapwood and heartwood were measured in August from 2013 to 2016.Important Findings Our results showed that the N concentration in bark decreased from the CC to the GC,while the opposite trend was found in sapwood and heartwood.Additionally,the C/N ratio in sapwood and heartwood of decay classes IV and V decreased from the CC to the GC,and the N/P ratio in heartwood of decay class V increased from the CC to the GC,implying that forest gaps have strong effects on C/N/P stoichiometry in highly decayed logs.Briefly,highly decayed logs are more susceptible to the microenvironment,and the proportion of highly decayed logs under the CC or the GC should be appropriately adjusted if necessary.

Pure and mixed plantations of Persian walnut (Juglans regia L.) for high quality timber production in Chile, South America

Aims Persian walnut(Juglans regia L.),an interesting forest species for the veneering industry,requires adequate management to produce valuable high-quality logs.Since species associations and management level can improve stand productivity,the novelty of this work was to assess Persian walnut performance in different planting mixtures and in pure plantations conditioned to management intensity.Methods Growth,straightness and survival measurements were taken annually for 7 years after planting pure and mixed plantations under two contrasting management scenarios.Diseases were recorded at Age 7 in all plantations.Under each management intensity,besides the monoculture,three mixtures were tested:a mixture of only main forest species,main forest species plus one arboreal companion species,Black alder(Alnus glutinosa L.)and main species plus the shrub Russian olive(Elaeagnus angustifolia L.)as nurse species.A test of interaction between plantation type and management scenario was conducted using repeated growth data.Important Findings The interaction was significant,indicating the presence of different mechanisms underlying plantation effects under high and low management level.Compared with pure plantations,Persian walnut associated with the nurse shrub exhibited 78%higher height and 53%higher diameter growth in plantations under low management.Health benefits(lower presence of walnut blight than in the monoculture)and better straightness were also found in the association including the shrub when the management intensity was not high.These beneficial effects in the presence of Russian olive were not present under high management intensity(irrigation,fertilization,tutoring and frequent pruning).Site-specific designs for Persian walnut plantations would depend on the foreseen management intensity.