Changes in hillslope hydrology in a perched,shallow soil system due to clearcutting and residual biomass removal     

Colin P. R. McCarter  Stephen D. Sebestyen  Susan L. Eggert  Randall K. Kolka  Carl P. J. Mitchell 《水文研究》2020,34(26):5354-5369

Sustainable fuels legislation and volatility in energy prices have put additional pressures on the forestry sector to intensify the harvesting of biomass for “advanced biofuel” production. To better understand how residual biomass removal after harvest affects forest hydrology in relatively low slope terrain, a Before-After-Control-Impact (BACI) study was conducted in the USDA Forest Service's Marcell Experimental Forest, Minnesota, USA. Hydrological measurements were made from 2010–2013 on a forested hillslope that was divided into three treatment blocks, where one block was harvested and residual biomass removed (Biomass Removed), the second was harvested and residual biomass left (Biomass Left), and the last block was left as an Unharvested Control. The pre-harvest period (2 years) was 2010–11 and post-harvest (2 years) was 2012–13. Water table elevation at the upslope and downslope position, subsurface runoff, and soil moisture were measured between May–November. Mixed effect statistical models were used to compare both the before-after and “control” treatment ratios (ratios between harvested hillslopes and the Unharvested Control hillslope). Subsurface runoff significantly increased (p < .05) at both harvested hillslopes but to a greater degree on the Biomass Left hillslope. Greater subsurface runoff volumes at both harvested hillslopes were driven by substantial increases during fall, with additional significant increases during summer on the Biomass Left hillslope. The hydrological connectivity, inferred from event runoff ratios, increased due to harvesting at both hillslopes but only significantly on the Biomass Left hillslope. The winter harvest minimized soil disturbance, resulting in no change to the effective hydraulic conductivity distribution with depth. Thus, the observed hydrological changes were driven by increased effective precipitation and decreased evapotranspiration, increasing the duration that both harvested hillslopes were hydrologically active. The harvesting of residual biomass appears to lessen hydrological connectivity relative to leaving residual biomass on the hillslope, potentially decreasing downstream hydrological impacts of similar forestry operations.  相似文献   

楼观台森林公园深层生态旅游开发的模式探讨   总被引：4，自引：1，他引：4  

于立新  孙根年 《山地学报》2006,24(6):727-733

提出了深层生态旅游开发的概念,构建了一个“两翼对接”模式。在广泛野外调查的基础上,依据上述理念和开发模型,针对楼观台国家森林公园的景观资源特征,对其深层生态旅游开发进行了系统设计。具体而言,重点突出了自然山水、生物景观和道教文化三方面设计,揭示了三大类60个景物的生态文化主题,设计了相应的开发展示模式和游客生态体验方式。其目的在于,提高森林公园生态文化的展示水平和加深旅游者的生态体验。  相似文献   

基于芬兰经验的我国森林资源型城市的发展研究--以伊春市为例     

姜琳琳  张宁  臧淑英 《世界地理研究》2006,15(2):48-53,65

资源型城市的可持续发展问题一直是学术界的研究热点,但对于森林资源型城市的研究却不多见。本文概括介绍了芬兰的资源和经济发展情况,系统分析了芬兰这样一个以森林起家的经济发达国家的成功经验;并以伊春为例提出了森林资源型城市经济转型和可持续发展可资借鉴的对策和建议。  相似文献   

Promoting social justice and conserving montane forest environments: a case study of Nepal's community forestry programme   总被引：1，自引：0，他引：1  

Netra Prasad Timsina 《The Geographical journal》2003,169(3):236-242

This paper analyses participatory forest policy and the ways it has influenced the relationships between people as it relates to the forest resource management. This case study was conducted in the middle hills of Nepal, and information was collected through direct observation, individual interviews, group discussion and secondary information analysis. It substantiates a few examples of how the community forestry programme can be used as a means to promote the participation of the women, the poor and dalit (untouchables) in forest resource management, as well as enhancing social justice and improving the forest resources in their locality. However, it also demonstrates that though the community forestry programme has a positive impact, it faces several constraints and challenges. The local Forest User Group is controlled by a few élites making the poor and disadvantaged vulnerable to further marginalization. The results of the case study strongly indicate that community forestry processes must address the political, economic and social needs of the forest users, and also provide a neutral platform on which the poor can present their cases.  相似文献   

State forestry and spatial scale in the development discourses of post-colonial Tanzania: 1961–1971     

Andrew Hurst 《The Geographical journal》2003,169(4):358-369

At independence, Tanzanian foresters believed that state-led forestry could provide a lasting contribution to the development aspirations of the newly independent country. Yet they were gradually marginalized within Julius Nyerere's project of socio-economic transformation. By exploring the spatial dimensions of competing land use discourses of the time, I hope to offer an interpretation as to how and why forestry's marginalization happened. I argue that at least some of this marginalization was the result of differences inherent in the scale of focus between forestry and the larger, contemporaneous socio-economic and political discourses dominant in the period. At independence, Nyerere positioned development efforts more squarely within the national political institutions of the state and for the nation, writ whole. With its professional and discursive ties to an international forestry order and its spatial biases, Tanzanian foresters were poorly placed to respond or adapt to changes in the political discourse and in the economic conditions of resource extraction. In short, they were unable to adjust to changes in the scale of development praxis in Tanzania. I conclude by suggesting two points. First, that the history of land use and natural resource management choices in post-colonial Tanzania can be better understood through a historical-geographical, or spatialized, theoretical framework. Second, that current historical-geographical theory could be fine tuned through reflection on its utility in describing and explaining land use politics in post-colonial developing contexts.  相似文献   

'Trees, forests and communities': some historiographical approaches to environmental history on Africa     

Karen Brown 《Area》2003,35(4):343-356

Focusing on the contested issue of trees and forests, this paper looks at various ways in which historians have explored environmental change and human agency in Africa. It looks in particular at the colonial period and positions the case of the Cape Colony (South Africa) in a broader historiographical context. Colonial silviculture involved both the appropriation of the natural forests and the creation of exotic plantations. These policies generated a mixture of reactions from African communities and had varying effects on the environment. Colonial science and the projects it gave rise to have since been critiqued, contributing to the promotion of community-based forestry schemes that try to incorporate indigenous knowledge and ideas about land use.  相似文献   

Natural recovery from accelerated forest ditch and stream bank erosion five years after harvesting of plantation forest on Plynlimon,mid‐Wales     

Tim Stott 《地球表面变化过程与地形》2005,30(3):349-357

Erosion rates surveyed using 230 erosion pins on 24 occasions over eight years (1994–2001) on forested stream banks, tributaries and forest ditches in the 0·89 km² Nant Tanllwyth catchment, part of the Hafren Forest on Plynlimon, mid‐Wales, showed statistically significant increases of up to 40 mm a^?1 in mean erosion rates during the two‐year period in which environmentally sensitive plot‐scale timber harvesting operations took place (1996–97). In the four years following timber harvesting mean erosion rates at all sites recovered to levels that were lower than before the harvesting operations began. This is attributed to increased light levels, following canopy removal, allowing vegetation to colonize exposed banks. There was a statistically significant relationship (p < 0·05) between mean erosion rate in 2000–01 (four years after harvesting) and percentage vegetation cover at erosion monitoring sites in the clearfelled (south tributaries) area though the same relationship did not hold for sites on the mainstream banks or for sites on the north (mature forest) ditch sites. The implications of natural vegetation colonization for management of such streams are discussed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

福建开展森林人家休闲健康游的探讨     

林彬  林贵民  陈静  周敏 《福建地理》2007,(3)

通过对国内开展乡村旅游现状的调研,分析了目前福建开展乡村旅游存在的问题,借鉴川、渝、浙等地乡村旅游"农家乐"的成功经验,结合福建依托森林资源特色开展森林人家的主要措施,对如何进一步提升森林人家品牌进行了探讨.  相似文献   

Exile and exclusion: The legacy of soviet forestry for villages in the north of Perm oblast     

Dominique Moran 《GeoJournal》2001,55(2-4):541-547

This paper explores the relationship between the forestry enterprises (leskhozi) and the inhabitants of forestry villages in the northern rayony of Perm oblast, Russian Federation in the context of the `new regional geography'. These relationships are compared with those identified between peasant farmers and collective and state farms post-1991, and a theory of the cultivation of these relationships as a coping mechanism for both households and enterprises facing difficult economic circumstances is advanced. The situation in the northern rayony is contextualised through discussion of the settlement and development history of the region, which was a recipient of forced and voluntary labour migration during the Soviet period. The paper concludes that in accordance with recent theories of post-communist regional development, the experience of transition in the northern rayony of Perm oblast is determined at least in part by its social and economic context. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Impacts of afforestation on groundwater resources and quality   总被引：4，自引：0，他引：4  

Alistair Allen  Deborah Chapman 《Hydrogeology Journal》2001,9(4):390-400

Plans to double the proportion of land under forest cover in Ireland by the year 2035 have been initiated. The plan, primarily financially driven, ignores potential environmental impacts of forestry, particularly impacts on groundwater resources and quality. Since groundwater supplies almost 25% of Ireland's total potable water, these impacts are important. Field investigations indicate that afforestation leads to a reduction in runoff by as much as 20%, mainly due to interception of rainfall by forest canopies. Clearfelling has the opposite impact. Implications are that uncoordinated forestry practices can potentially exacerbate flooding. Groundwater recharge is affected by forestry, largely due to greater uptake of soil water by trees and to increased water-holding capacity of forest soils, arising from higher organic contents. Recharge rates under forests can be reduced to one tenth that under grass or heathland. Groundwater quality may be affected by enhanced acidification and nitrification under forests, due partly to scavenging of atmospheric pollutants by forest canopies, and partly to greater deposition of highly acid leaf litter. The slower recharge rates of groundwater under forests lead to significant delays in manifestation of deterioration in groundwater quality. Electronic Publication  相似文献