采用LFA(Landscape Function Analysis)方法,通过调查7种地类35组样本,评价植被类型、人类活动对林地景观功能和土壤性能的影响,并验证LFA方法在黄土区的适用性。结果表明:不同植被类型对林地土壤结构稳定性、渗透性能、养分循环性能的...采用LFA(Landscape Function Analysis)方法,通过调查7种地类35组样本,评价植被类型、人类活动对林地景观功能和土壤性能的影响,并验证LFA方法在黄土区的适用性。结果表明:不同植被类型对林地土壤结构稳定性、渗透性能、养分循环性能的影响显著,其中,天然次生林改良土壤结构稳定性、渗透性和养分循环性能的作用最好,其次是刺槐人工林、油松人工林,荒草坡最差;人类活动对人工林地景观功能和林地土壤结构稳定性有显著影响;LFA方法能够较好地评价植被类型对林地土壤性能的影响,以及人类活动对人工林地景观功能和林地土壤结构稳定性的影响,在黄土残塬沟壑区有较好的适用性。展开更多
Landscape pathology is a research approach that can provide validation of the effectiveness of regional controls of forest disease at a landscape scale. In this paper, we analyzed the effects of stand features, manage...Landscape pathology is a research approach that can provide validation of the effectiveness of regional controls of forest disease at a landscape scale. In this paper, we analyzed the effects of stand features, management approaches, and geographical locations on poplar canker disease incidence （DI） and disease severity index （DSI） of individual trees at a 10 km x 10 km mesoscale landscape in Qingfeng County, China. DI varied significantly with stand age, tree densities, and the degree of canopy closure. DI in stands younger than 4 years old was significantly lower than that in the stands over 6 years old and reached the highest value at a stand age of 8-10 years. Overall, DI was positively correlated with stand age, stand density, andthe degree of canopy closure. DI was significantly lower in agro-forest stand patches than in other three patch types, i.e. isolated patch, pure stand patch, and mixed stand patch. Poplar plantations distributed around and near to villages exhibited significantly higher DI mainly due to human activities and herbivores. Fragmentation or connectivity in this mesoscale landscape seemed not impact disease occurrence. DSI was not significantly correlated with stand density, but varied significantly with tree varieties and trees ages. DSI was highest in stands of 10-12 year trees for all poplar varieties we studied here. Plantation density and plantation age were thus critical factors in determining DI and DSI. A logistic predictive model of disease occurrence was developed for the study area, considering varieties, age, height, density, canopy cover, stand types, patch types, management status, and stand geographical locations. Our study here shows that adjustment of stand density by thinning at different plantation ages is an effective approach controlling the occurrence canker disease in short-rotation poplar plantations at the landscape scale.展开更多
Peatland in Southeast Asia has an important function in the provision of ecosystem services such as carbon sink, climate regulation, water supply, biodiversity, and others. Recurrent fires in the peatland, especially ...Peatland in Southeast Asia has an important function in the provision of ecosystem services such as carbon sink, climate regulation, water supply, biodiversity, and others. Recurrent fires in the peatland, especially in Indonesia, have changed peatland functions from carbon sequestration to carbon emission, causing severe environmental and economic problems. Fire prevention requires an understanding of the factors affecting fire in peatland. We compared fire occurrences in 2014 between different land cover types, land management systems, landholders, and proximity to roads and canals in Riau Province, Indonesia. Remote sensing and field data were collected and analyzed. Shrubland was the most fire-prone land cover, while plantations and mangrove forests were the least. Shrubland has high fire occurrence regardless of land management and landholder type. Peat swamp forests that are allowed to be utilized were more fire-prone than conserved peat swamp forests. Oil palms from unregistered companies had more fires than those from registered companies and smallholders. Coconut and sago plantations from companies had more fires than smallholder cultivation. Proximity to roads and canals affects the occurrence of fires in peat swamp forests;however, proximity had less of an effect on fire occurrence in shrubland. The high percentage of burned areas in shrubland showed that land cover was a major factor that affects fire in peatland, followed by land management, landholders, and proximity to roads and canals. These findings indicate the importance of law enforcement and land management systems, management schemes by different landholders, and the spatial arrangement of land cover, roads, and canals for integrated peatland management and restoration of shrubland into peat swamp forest and other fire-resistant land cover types with sustainable production.展开更多
By analyzing the present situation and advantages of tea plantations in Helong Township,Ya'an City,the construction modes of rural landscape and ecological tea plantation were studied from the perspective of lands...By analyzing the present situation and advantages of tea plantations in Helong Township,Ya'an City,the construction modes of rural landscape and ecological tea plantation were studied from the perspective of landscape ecology.展开更多
文摘采用LFA(Landscape Function Analysis)方法,通过调查7种地类35组样本,评价植被类型、人类活动对林地景观功能和土壤性能的影响,并验证LFA方法在黄土区的适用性。结果表明:不同植被类型对林地土壤结构稳定性、渗透性能、养分循环性能的影响显著,其中,天然次生林改良土壤结构稳定性、渗透性和养分循环性能的作用最好,其次是刺槐人工林、油松人工林,荒草坡最差;人类活动对人工林地景观功能和林地土壤结构稳定性有显著影响;LFA方法能够较好地评价植被类型对林地土壤性能的影响,以及人类活动对人工林地景观功能和林地土壤结构稳定性的影响,在黄土残塬沟壑区有较好的适用性。
基金supported by the twelfth five-year science and technology support program of China(2012BAD19B0801)
文摘Landscape pathology is a research approach that can provide validation of the effectiveness of regional controls of forest disease at a landscape scale. In this paper, we analyzed the effects of stand features, management approaches, and geographical locations on poplar canker disease incidence （DI） and disease severity index （DSI） of individual trees at a 10 km x 10 km mesoscale landscape in Qingfeng County, China. DI varied significantly with stand age, tree densities, and the degree of canopy closure. DI in stands younger than 4 years old was significantly lower than that in the stands over 6 years old and reached the highest value at a stand age of 8-10 years. Overall, DI was positively correlated with stand age, stand density, andthe degree of canopy closure. DI was significantly lower in agro-forest stand patches than in other three patch types, i.e. isolated patch, pure stand patch, and mixed stand patch. Poplar plantations distributed around and near to villages exhibited significantly higher DI mainly due to human activities and herbivores. Fragmentation or connectivity in this mesoscale landscape seemed not impact disease occurrence. DSI was not significantly correlated with stand density, but varied significantly with tree varieties and trees ages. DSI was highest in stands of 10-12 year trees for all poplar varieties we studied here. Plantation density and plantation age were thus critical factors in determining DI and DSI. A logistic predictive model of disease occurrence was developed for the study area, considering varieties, age, height, density, canopy cover, stand types, patch types, management status, and stand geographical locations. Our study here shows that adjustment of stand density by thinning at different plantation ages is an effective approach controlling the occurrence canker disease in short-rotation poplar plantations at the landscape scale.
文摘Peatland in Southeast Asia has an important function in the provision of ecosystem services such as carbon sink, climate regulation, water supply, biodiversity, and others. Recurrent fires in the peatland, especially in Indonesia, have changed peatland functions from carbon sequestration to carbon emission, causing severe environmental and economic problems. Fire prevention requires an understanding of the factors affecting fire in peatland. We compared fire occurrences in 2014 between different land cover types, land management systems, landholders, and proximity to roads and canals in Riau Province, Indonesia. Remote sensing and field data were collected and analyzed. Shrubland was the most fire-prone land cover, while plantations and mangrove forests were the least. Shrubland has high fire occurrence regardless of land management and landholder type. Peat swamp forests that are allowed to be utilized were more fire-prone than conserved peat swamp forests. Oil palms from unregistered companies had more fires than those from registered companies and smallholders. Coconut and sago plantations from companies had more fires than smallholder cultivation. Proximity to roads and canals affects the occurrence of fires in peat swamp forests;however, proximity had less of an effect on fire occurrence in shrubland. The high percentage of burned areas in shrubland showed that land cover was a major factor that affects fire in peatland, followed by land management, landholders, and proximity to roads and canals. These findings indicate the importance of law enforcement and land management systems, management schemes by different landholders, and the spatial arrangement of land cover, roads, and canals for integrated peatland management and restoration of shrubland into peat swamp forest and other fire-resistant land cover types with sustainable production.
文摘By analyzing the present situation and advantages of tea plantations in Helong Township,Ya'an City,the construction modes of rural landscape and ecological tea plantation were studied from the perspective of landscape ecology.
