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Comparison of foliar nutrient concentrations between natural and artificial forests of Pinus sylvestris var. mongolica on sandy land, China 被引量:7
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作者 ZHU Jiao-jun TAN Hui +1 位作者 KANG Hong-zhang XU Mei-ling 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期177-184,共8页
In order to examine the causes of degradation of Pinus sylvestris var. mongolica plantations on sandy land, the foliar concentrations of N, P, K and C were analyzed and compared between the field grown P. sylvestris v... In order to examine the causes of degradation of Pinus sylvestris var. mongolica plantations on sandy land, the foliar concentrations of N, P, K and C were analyzed and compared between the field grown P. sylvestris var. mongolica trees from two provenances (natural forests and plantations). The results indicated that natural tree needles had lower N, P and C concentrations, and higher K concentrations than those of plantation tree needles. For plantation tree needles, ratios of N: P, P. K and N: K increased with tree age before 45 years old; but they were not clear for the natural tree needles. Compared with the conclusions reported on Pinus spp., we found that the foliar N and P concentrations were in the optimal range for both natural and plantation tree needles. This result suggested that N or P might not be the absolute limit factors in plant nutrient for P sylvestris var. mongolica on sandy land. However, foliar K concentrations in both natural and plantation tree needles were much lower than those reported on Pinus spp. (〉4.80 g kg-1).The N: P ratio of natural needles was in the adequate ranges, but N: P ratio of plantation needles was out of the adequate ranges. These results indicated that there was a better balanced nutrition status in the natural forest than in the plantations. If only considering the foliar nutrient concentrations of P sylvestris var. mongolica from different provenances, it might be concluded that the degradation phenomenon of P. sylvestris var. mongolica plantations was not induced by nutrition deficiency of absolute nutrients of N and P, but might be induced by other mineral nutrients or by the effectiveness of N and P nutrients. The unbalanced nutrition status and relatively quick decomposition of needles in the plantations might also contribute to the degradation. 展开更多
关键词 Degradation phenomenon Forest ecosystem on sandy land N: P ratio natural Mongolian pine Pinus sylvestris var. mongolica Plantation Mongolian pine
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Testing of Decision Making Tools for Village Land Use Planning and Natural Resources Management in Kilimanjaro Region 被引量:1
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作者 Anthony Z. Sangeda Frederick C. Kahimba +3 位作者 Reuben A. L. Kashaga Ernest Semu Christopher P. Mahonge Francis X. Mkanda 《Open Journal of Soil Science》 2014年第13期446-458,共13页
This paper focuses on participatory testing of decision making tools (DMTs) at village level to assist in development of land use plans (LUPs) for sustainable land management (SLM) in Kilimanjaro Region, Tanzania. Dat... This paper focuses on participatory testing of decision making tools (DMTs) at village level to assist in development of land use plans (LUPs) for sustainable land management (SLM) in Kilimanjaro Region, Tanzania. Data were collected using conditional surveys through key informant interviews with the project’s district stakeholders in each district, focused group discussions with selected villagers and participatory mapping of natural resources. Soil health, land degradation, carbon stock, and hydrological conditions were assessed in the seven pilot villages in all seven districts using DMTs as part of testing and validation. Results indicated soils of poor to medium health, and land degradation as portrayed by gullies and wind erosion in lowlands and better in uplands. Carbon and forest disturbance status could not be assessed using one-year data but hydrological analysis revealed that water resources were relatively good in uplands and poor in the lowlands. Challenges with regard to land use include increased gully erosion, decreased stream flow, reduced vegetation cover due to shifting from coffee with tree sheds to annual crops farming, cultivation near water sources, and overgrazing. Empowering the community with decision making tools at village level is essential to ensure that village land uses are planned in a participatory manner for sustainable land and natural resources management in Kilimanjaro and other regions in Tanzania. 展开更多
关键词 DECISION Making Tool land Use Planning Sustainable land MANAGEMENT natural RESOURCES MANAGEMENT KILIMANJARO
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Soil water movement and deep drainage through thick vadose zones on the northern slope of the Tianshan Mountain: Croplands vs.natural lands 被引量:3
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作者 Fang-qiang Sun Li-he Yin +6 位作者 Wu-hui Jia Jun Zhang Xiao-yong Wang Li-feng Zhu Xin-xin Zhang Xiao-ping Tang Jia-qiu Dong 《China Geology》 2020年第1期113-123,共11页
Regional aridity is increasing under global climate change,and therefore the sustainable use of water resources has drawn attention from scientists and the public.Land-use changes can have a significant impact on grou... Regional aridity is increasing under global climate change,and therefore the sustainable use of water resources has drawn attention from scientists and the public.Land-use changes can have a significant impact on groundwater recharge in arid regions,and quantitative assessment of the impact is key to sustainable groundwater resources management.In this study,the changes of groundwater recharge after the conversion of natural lands to croplands were investigated and compared in inland and arid region,i.e.,the northern slope of the Tianshan Mountain.Stable isotopes suggest that soil water in topsoil(<2 m)has experienced stronger evaporation under natural lands than croplands,and then moves downward as a piston flow.Recharge was estimated by the tracer-based mass balance method,i.e.,chloride and sulfate.Recharge rates under natural conditions estimated by the chloride mass balance(CMB)method were estimated to be 0.07 mm/a in deserts and 0.4 mm/a in oases.In contrast,the estimated groundwater recharge ranged from 61.2 mm/a to 44.8 mm/a in croplands,indicating that groundwater recharge would increase significantly after land changes from natural lands to irrigated croplands in arid regions.Recharge estimated by the sulfate mass balance method is consistent with that from the CMB method,indicating that sulfate is also a good tracer capable of estimating groundwater recharge. 展开更多
关键词 land-use Soil water Groundwater recharge Deep drainage Unsaturated zone Arid regions CROPland natural land Groundwater survey engineering Tianshan Mountain China
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Natural regeneration characteristics of Pinus sylvestris var. mongolica forests on sandy land in Honghuaerji, China 被引量:20
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作者 ZHU Jiao-jun KANG Hong-zhang +2 位作者 TAN Hui XU Mei-ling WANG Jun 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期253-259,共7页
在蒙古的松的自然新生, Pinus sylvestris var。蒙古人集成通信适配器,在中国的 Honghuaerji 的森林(自然的蒙古的松的原版,砂土上的森林) 在 2004 被学习。新生索引的全部的平均值在成熟看台是更高的(超过 80% 单个茎比 50 年旧) ... 在蒙古的松的自然新生, Pinus sylvestris var。蒙古人集成通信适配器,在中国的 Honghuaerji 的森林(自然的蒙古的松的原版,砂土上的森林) 在 2004 被学习。新生索引的全部的平均值在成熟看台是更高的(超过 80% 单个茎比 50 年旧) ,新生索引 reached29 幼苗· m~ 的最大值(有在更年轻的看台的最低价值的 -2), ,例如,在里面 32 年旧并且 43-yearold 看台。看台年龄是决定自然新生的一个重要因素,它是在在这调查的更旧的看台的最好(例如关于 80 年旧) 。新生索引似乎不是仔细在与华盖坦诚的关系尽管蒙古的松是 photophilictree 种。在差距的每种类型,自然新生很好。新生索引在圆差距在南方和东方边是令人满意的;并且在东方, thenarrow 平方的边豁开。结果显示了那蒙古消瘦,幼苗能忍受 shadingunderstory,但是它不进入没有差距或大骚乱的华盖层,例如,火,弯屈 / 下雪损坏或清楚的切等等。这些结果可以潜在地提供参考书给蒙古的松的管理和造林,砂土在上的种植园干旱并且 semi-aridareas。象新生,结构和生态的条件上的全面比较那样的研究以后应该等等在自然的蒙古的松,森林和种植园之间被进行。 展开更多
关键词 森林资源 天然更新 林窗 森林系统 林分郁闭度
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Urban Expansion and Its Influencing Factors in Natural Wetland Distribution Area in Fuzhou City,China 被引量:8
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作者 CAI Yuanbin ZHANG Hao +2 位作者 PAN Wenbin CHEN Yanhong WANG Xiangrong 《Chinese Geographical Science》 SCIE CSCD 2012年第5期568-577,共10页
This paper principally focuses on land use dynamics,urban expansion and underlying driving forces in the Natural Wetland Distribution Area(NWDA)of Fuzhou City in the southeastern China.Based on time series Landsat TM/... This paper principally focuses on land use dynamics,urban expansion and underlying driving forces in the Natural Wetland Distribution Area(NWDA)of Fuzhou City in the southeastern China.Based on time series Landsat TM/ETM+imageries and historical data,relationships between urban land expansion and its influencing factors from 1989 to 2009 were analyzed by using an integrated approach of remote sensing(RS)and geographic information system(GIS)techniques.The results showed that built-up land increased from 151.16 km2in 1989 to 383.76 km 2in 2009. Approximately 64.25%of the newly emerging built-up land was converted from cropland(29.47%),forest and shrub (25.78%),water(3.73%),wetland(4.61%),and bare land(0.66%)during 1989 and 2009.With a remarkable decrease in cropland,the proportion of non-agricultural population increased by 23.6%.Moreover,rapid development of infrastructures,facilities,industrial parks,and urban and rural settlements along the Minjiang River resulted in the eastward and southward expansion of built-up land.Additionally,the growth pattern of built-up land in the NWDA is highly correlated with socio-economic factors,including the gross domestic product(GDP),GDP per capita,and structure of industry.As a result,the observed environmental degradation such as loss of cropland and wetland due to heavy pressure of rapid urbanization have greatly impaired the carrying capacity of city.Thus,in addition to scientific and rational policies towards minimizing the adverse effects of urbanization,coordination between the administrative agencies should be urgently strengthened to balance the conflicts between urban development and ecological conservation to make sure the sustainable land use. 展开更多
关键词 中国东南部 天然湿地 城市扩展 影响因素 分布区 福州市 人均国内生产总值 landSAT
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Analysis of Land Use and Land Cover Changes and Evaluation of Natural Generation and Potential Restoration Areas in the Mexican Huasteca Region 被引量:1
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作者 Carmelo Peralta-Rivero Carlos Contreras-Servín +2 位作者 María G.Galindo-Mendoza Jean-Francois Mas Caussel Marcos Algara-Siller 《Open Journal of Forestry》 2014年第2期124-135,共12页
This study aims to analyze temporal changes in land use and land cover change (LUCC) as well as identify areas for natural regeneration and potential areas for forest restoration in the Huasteca region for the period ... This study aims to analyze temporal changes in land use and land cover change (LUCC) as well as identify areas for natural regeneration and potential areas for forest restoration in the Huasteca region for the period from 1976 to 2007. Changes were quantified in numbers and, additionally, cartography was used to identify and map the main affected areas. Different models based on Geographic Information Systems (GIS) demonstrated that LUCC have occurred on an area of 11718.82 km2, representing 17.84% of the region’s surface. Agriculture and the growth of pasture could be identified as the main human-induced activities that have led to landscape modification. In addition, forest cover is affected by a deforestation rate which is higher than the national average. Further important changes include a change from natural land cover to non-original land cover, affecting an area of 4911.88 km2 in the period from 1976-1993, and an area of 1892.5 km2 in the period from 1993-2002. Smaller changes could be observed for the period from 1993-2002 with an affected area of 1029.78 km2. At the same time, a natural regeneration from nonoriginal to original land cover took place from 1976-1993 on an area of 1318.68 km2, and also on an area of 974.18 km2 between 1993 an 2002. The surface that underwent a natural regeneration of forest cover made up 1932.07 km2. At the same time, an area of 5739.29 km2 for potential forest restoration was identified. Drawing on GIS methods and techniques, the development of thematic maps for land use, land use and land cover changes for the years of analysis (1976-1993-2002-2007) proved to be very adequate for the evaluation and analysis of the land cover and land use change, in particular with regard to the decrease of natural vegetation cover. 展开更多
关键词 land User land Cover natural Regeneration Forest Restoration LUCC GIS Temporal Analysis Huasteca
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The background features of natural environment and the harnessing pattern for the spread of saline land in the Songnen Plain
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作者 ZHANG BaiChangchun Institute of Geography, CAS, Changchun 130021 CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第2期92-96,共5页
The Songnen Plain lying in the central part of the Northeast China Plain covers an area of about 170 000 km2. There are vast patches of saline land, which are still in the process of enlargement. The spread of saline ... The Songnen Plain lying in the central part of the Northeast China Plain covers an area of about 170 000 km2. There are vast patches of saline land, which are still in the process of enlargement. The spread of saline land has already caused the worsening of ecoenvironment and hindered agricultural development in the region. The paper analyses background factors of natural environment that caused the spread of saline land according to the information of Landsat TM images. The result shows that among the three kinds of lakes the fault lake is the background factor of natural environment that causes the spread of saline land under arid conditions. Its lakebeach meadows could not recover from the excessive utilization in farming and stockraising. The proposed countermeasures to prevent and control the spread of saline land serve as biological steps or water conservancy facilities to protect the lakebeach meadows of the fault lakes from being artificial excessively utilized. 展开更多
关键词 spread of saline land background factors natural environment fault lake lakebeach meadow.
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Evaluation of natural forest regeneration as a part of land restoration in the Khentii massif,Mongolia
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作者 David Juricka Antonın Kusbach +6 位作者 Jana Parılkova Jakub Houska Pavlına Ambrozova Vaclav Pecina Zdena Rosicka Martin Brtnicky Jindrich Kynicky 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1773-1786,共14页
Forest stands in the semi-arid environment of northern Mongolia have an essential role in controlling ongoing desertification in the surrounding landscape.Over the last decade,the total forest area has decreased drama... Forest stands in the semi-arid environment of northern Mongolia have an essential role in controlling ongoing desertification in the surrounding landscape.Over the last decade,the total forest area has decreased dramatically.The aim of this study was to evaluate the potential of natural regeneration as an essential element for ensuring sustainability of these forests.Based on field measurements from 120 plots in six sites,our assessment tool revealed five qualitative categories of forest regeneration,allowing us to assess impacts of both grazing and environmental conditions on the regeneration process.Grazing is a crucial factor and adversely affects regeneration.For sites with relatively low grazing intensity,low soil moisture levels represent the main reason for reduced regeneration.The approach to classification proposed in this study allows for the identification and interpretation of stand conditions where natural regeneration has failed.This study provides an important foundation to inform decisionmaking related to land protection and restoration actions.Our findings could be used in comparative studies and,importantly,may aid further mapping of Mongolian forests. 展开更多
关键词 Mongolia natural forest regeneration SEEDLINGS Larix sibirica land restoration DESERTIFICATION
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Assessing the Effect of Natural Controls and Land Use Change on Sediment Yield in a Major Andean River:The Magdalena Drainage Basin,Colombia 被引量:4
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作者 Juan Dario +5 位作者 Restrepo James P. M. Syvitski 方海燕(译) 《AMBIO-人类环境杂志》 2006年第2期65-74,4,共10页
马格达莱纳河是哥伦比亚安第斯山区的一个世界级的河流网络,该河流年产沙量约为150Mt,是全世界10大主要产沙河流之一。在本研究中,我们探讨主要自然因子和人类活动对马格达莱纳河流域产沙模式的影响,重建该区森林砍伐和农业活动时... 马格达莱纳河是哥伦比亚安第斯山区的一个世界级的河流网络,该河流年产沙量约为150Mt,是全世界10大主要产沙河流之一。在本研究中,我们探讨主要自然因子和人类活动对马格达莱纳河流域产沙模式的影响,重建该区森林砍伐和农业活动时空模式,探讨土地利用变化与产沙趋势的关系。我们的研究结果表明,整个马格达莱纳河流域的产沙量可以用自然变量(包括径流量和最大河水流量)来解释。这两个因子解释了产沙量58%的变化。含沙率和土地利用的时间分析表明,在过去10~20年里流域侵蚀呈现增加的趋势。许多人类活动的影响,包括森林覆被在20年里减小了近40%.农业和牧场增加了65%、土壤保持差、开矿活动,以及城市化的加速,都促进了该地区域尺度上产沙量的增加。 展开更多
关键词 Assessing the Effect of natural Controls and land Use Change on Sediment Yield in a Major Andean River
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Comparing the climate change mitigation potentials of alternative land uses:Crops for biofuels or biochar vs.natural regrowth
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作者 Anne Cecilie Løvenskiold Xiangping Hu +1 位作者 Wenwu Zhao Francesco Cherubini 《Geography and Sustainability》 2022年第4期347-357,共11页
Using biomass from dedicated crops for energy production and natural vegetation regrowth are key elements in future climate change mitigation scenarios.However,there are still uncertainties about the mitigation potent... Using biomass from dedicated crops for energy production and natural vegetation regrowth are key elements in future climate change mitigation scenarios.However,there are still uncertainties about the mitigation potentials that can be achieved by the different land-based systems and how they perform relative to each other.In this study,we use harmonized future land use datasets to identify global land areas dedicated to second generation bioenergy crop production in 2050 under different climate scenarios.We then assess the global climate change mitigation potentials of using biomass for producing bioethanol with(BECCS)or without carbon capture and storage,biochar,or a synthetic fuel(e-methanol).For the latter,the electricity required to produce hydrogen for e-methanol synthesis is sourced from either wind power or the projected average electricity mix in 2050.Mitigation potential from natural regrowth on the identified land is also quantified.For all the cases,we modelled emissions of greenhouse gases from the life-cycle stages and use parameterized models to estimate local biomass growth rates.The identified land areas range from 1.95 to 13.8 million hectares and can provide from 30 to 178 mega ton(Mt)dry biomass annually from dedicated crops.Climate change mitigation potentials range from 11 to 257 MtCO_(2)-eq.yr^(−1),depending on technological option and land availability.The largest mitigation is delivered by BECCS,but e-methanol can achieve similar findings when hydrogen is sourced from wind power.If hydrogen is produced from grid electricity,e-methanol can result in net positive emissions.E-methanol can also deliver more final energy than bioethanol(4.04 vs.1.27 EJ yr^(−1)).Natural vegetation regrowth can generally achieve higher mitigation than bioethanol,but less than biochar.An optimal combination of BECCS and natural vegetation regrowth can achieve a larger mitigation,up to 281 MtCO_(2)-eq.yr^(−1),indicating that integrated solutions can help to achieve successful land management strategies for climate change mitigation. 展开更多
关键词 Negative emission technologies natural regrowth land management Bioenergy systems Carbon neutrality
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Reporting on Land as Natural Capital by Gold Mining Houses in South Africa
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作者 Anet Smit TK Bungane 《Management Studies》 2019年第4期300-314,共15页
Motivated by the increasing popularity and advocating for integrated reporting by companies on their operations,the aim of this paper is to determine the disclosure levels on land by mining houses in South Africa in t... Motivated by the increasing popularity and advocating for integrated reporting by companies on their operations,the aim of this paper is to determine the disclosure levels on land by mining houses in South Africa in their integrated reports.Developing countries,such as South Africa should ensure sustainability of their natural resources in their endeavour of growing their economies.The mining sector in South Africa is a huge contributor to the economy,but also has a significant impact on land conservation.The complexity of mining activities and impacts thereof make it challenging for organisations to disclose information on land.This paper is descriptive by design;it contains a literature review,followed by a content analysis of the mining houses integrated reports by using a checklist.The checklist was based on recommendations by the Global Reporting Initiative(GRI)guidelines as to what the content of the integrated report on land should be.Fourteen mining houses operating in South Africa and registered on the Johannesburg Stock Exchange(JSE)were identified and analysed for this study.The findings of the paper display low levels of overall disclosure on land by the South African mining companies.However,there were high levels of disclosure for EN11,EN12,and MM1 sector-specific supplement in the integrated reports.Low levels of disclosure by the mining companies were evident in MM2 the sector-specific recommendations as well as the physical and monetary information related to MM2. 展开更多
关键词 natural CAPITAL environmental impact land MINING Global REPORTING INITIATIVE 4 integrated REPORTING
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Land Use/Cover and Naturalness Changes for Watershed Environmental Management(Southeastern Brazil)
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作者 Romulo Theodoro Costa Camila Francisco Goncalves +1 位作者 Angela Terumi Fushita José Eduardo dos Santos 《Journal of Geoscience and Environment Protection》 2017年第11期1-14,共14页
Driving forces on the landscape require regional management and/or local actions, together with other external factors. To operationalize this approach, this paper carried out a comparative analysis of the naturalness... Driving forces on the landscape require regional management and/or local actions, together with other external factors. To operationalize this approach, this paper carried out a comparative analysis of the naturalness dynamics of the Jacaré-Gua&#231u and Jacaré-Pepira watershed, based on land use/cover changes and a structural indicator of the landscape, over the 10-year (2004-2014), as support opportunities for improving its environmental planning and management. Land use/cover dynamics were obtained based on screen digitizing of LandSat imagery, using polygon manual digitalization. Naturalness scenarios of the watersheds, over the 10-year (2004-2014), were obtained based on Urbanity Indicator, which evaluates how much the natural landscapes are dominated by altered systems. The total area of watersheds showed a predominantly scenario, induced by anthropogenic agricultural and non-agricultural expansion areas, mainly by conversion of other land use/cover types in sugarcane cultivation. Despite the increase in natural vegetation areas, over the 10-year (2004-2014), Jacaré-Gua&#231u and Jacaré-Pepira watersheds are far from a sustainable condition. However Jacaré-Gua&#231u watershed presents a scenario of more committed naturalness due to the increase in Urbanity Index values ≥ 0.7. The historical process of land use occupation for agricultural production remains the main driving force of naturalness changes, occupying more than 70% of the total area of watersheds. These results have significant implications for fast urbanizing municipalities in providing key information about long term land use impact on the watershed structure and function, making it possible for policy makers, scientists and stakeholders to identify land uses which are hindered or enhanced under various scenarios of land use change over the time, and making it possible to explore the trade-offs between them to improve watershed management. 展开更多
关键词 land Use Changes Urbanity Index Loss natural Capital Watershed Sustainable Management
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Impact Factors on Distribution and Characteristics of Natural Plant Community in Reclamation Zones of Changjiang River Estuary 被引量:2
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作者 SUN Yongguang LI Xiuzhen +4 位作者 HE Yanlong JIA Yue MA Zhigang GUO Wenyong XIN Zaijun 《Chinese Geographical Science》 SCIE CSCD 2012年第2期154-166,共13页
To identify impact factors on the distribution and characters of natural plants community in reclamation area, with survey data from 67 plant quadrats in July 2009, soil properties data from 216 sampling points in Apr... To identify impact factors on the distribution and characters of natural plants community in reclamation area, with survey data from 67 plant quadrats in July 2009, soil properties data from 216 sampling points in April 2009, and TM (30 m) data in 2006, the composition and characteristics of natural plants community in different time of the Fengxian area in the Changjiang (Yangtze) River estuary were analyzed with two-way indicator species analysis (TWINSPAN), multivariate analysis of variance (MANOVA), detrended canonical correspondence analysis (DCCA) and canonical correspondence analysis (CCA). The results show that: 1) The plant communities in the reclaimed area are mainly mesophytes and helophytic-mesophytic transitional communities, showing a gradient distribution trend with the change in reclamation years. Species richness (MA), species diversity (H) and above-ground biomass also increase with the increase of reclamation years. Nevertheless, they appear to decline slightly in the middle and late reclamation period (> 30 years). 2) With the rise in land use levels, the changes in species richness and species diversity tend to increase at first and then decrease; species dominance (D), however, tends to decline; and above-ground biomass increases slightly. 3) The distribution of the plant community is mainly influenced by the following factors: land use levels (R = 0.55, p < 0.05), soil moisture (R = 0.53, p < 0.05), soil salinity (R = 0.43, p < 0.05) and reclamation time (R = 0.40, p < 0.05). 展开更多
关键词 植物群落特征 影响因素 填海区 长江口 除趋势典范对应分析 TWINSPAN分类 天然植物成分 DCCA排序
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Landscape influences and management countermeasures of ginseng planting near Changbai mountain nature reserve
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作者 Mingfang Tang Sha Qiu +3 位作者 Lijie Liu Tao Li Shanlin Li Tianshu Yu 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第6期1939-1948,共10页
Ginseng planting in Northeast China brings economic benefits but affects forest landscape integrity and native ecological processes.In order to quantify the impacts of ginseng planting on the forest landscape,Fusong C... Ginseng planting in Northeast China brings economic benefits but affects forest landscape integrity and native ecological processes.In order to quantify the impacts of ginseng planting on the forest landscape,Fusong County in Jilin Province was selected as a study area.The number and distribution of ginseng fields over different time was quantified based on remote sensing and ground surveys.Grid analysis and multiple regression analysis were used to study the impacts of ginseng planting on the landscape.The results showed that altitudes and slopes of ginseng fields increased and became increasingly scattered and smaller closer to the Changbai Mountain Nature Reserve.Ginseng fields and abandoned fields increased total patches and total area of the local forested landscape,and shared edge lengths between ginseng fields and forests,resulting in continuous fragmentation of the landscape.Although the total area of existing and abandoned ginseng fields accounts for a small fraction of the total landscape,their negative impacts on ecosystem conservation is significant.The local government needs to rationally plan ginseng planting,scientifically implement the restoration of abandoned ginseng lands,and enhance awareness of ginseng farmers to environmental stewardship.Our study has important significance for maintaining the healthy and stable development of the local ginseng industry and for improving the quality of regional ecological environment. 展开更多
关键词 Ginseng planting Agroforestry system land use landscape fragmentation Forest degradation Changbai Mountain nature Reserve
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Humus horizon development during natural forest succession process in the Polish Carpathians
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作者 Justyna SOKOŁOWSKA Agnieszka JÓZEFOWSKA Tomasz ZALESKI 《Journal of Mountain Science》 SCIE CSCD 2022年第3期647-661,共15页
As a result of socio-economic changes and land abandonment,the main ecological driver of the Carpathian landscape is the progression of the natural forest succession process.Thus,aspects of this process have become wo... As a result of socio-economic changes and land abandonment,the main ecological driver of the Carpathian landscape is the progression of the natural forest succession process.Thus,aspects of this process have become worthy of attention,especially in the context of carbon sequestration and the management of protected areas.Soil processes,especially within the topsoil,are some of the most susceptible to change,due to the accumulation of organic matter during such land-use transformations.The purposes of this study were to investigate the differences in topsoil development using the A Horizon Development Index(ADI)and to study the composition of humic substances and advanced organic matter humification in different land-use areas in selected Carpathian national parks,i.e.Bieszczady,Magura and Pieniny National Parks in southern Poland.Additionally,a goal of this study was to compare the ADI and the spectroscopic coefficients of humic substances as indicators of the degree of humus horizon shaping as well as advanced organic matter humification.In total,ten transects were selected,each consisting of three different land-use areas:semi-natural meadow,successional forest and old-growth forest.Soil colour was determined in fresh and air-dried samples using the Munsell colour chart.In air-dried soil samples p H,soil texture,total organic carbon and total nitrogen were measured.Humic substances were extracted and further characterized by UV-VIS spectroscopy.The ADI confirmed the influence of natural forest succession on soil colour darkening and the development of the uppermost soil layer.Spectroscopic analyses of humic substances showed two different patterns depending on soil depth.In the 0–10 cm layer,natural forest succession reduced the rate of the humification process and decreased the degree of maturity of fulvic acids;in the 10–20 cm layer,it led to an increase in the rate of the humification process and a decrease in the content of humic and fulvic acids at the beginning of the transformation.The comparison of two different indicators of soil development–the ADI and the spectroscopic coefficients of humic substances(Q_(4/6),Q_(2/4),Q_(2/3),Δlog K)–indicated that these indexes are based on different features of soil and cannot be used interchangeably. 展开更多
关键词 land use changes natural forest succession Polish Carpathians landscape transformation Protected areas management Humic substances
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Application of the Distance to Natural (D2N) Index and Statistical Analysis of Different Anthropic Uses of the Río Grande De Comitán Watershed, Chiapas, México
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作者 Flor Magali Aguilar López Dayana Almeida +6 位作者 Yuri Tavares Rocha Eliziane Carla Scariot Waldir José Gaspar Roberto Bonifaz Alfonzo Elisabete Maria Zanin Alberto Carvalho Peret José Eduardo Dos Santos 《Journal of Geoscience and Environment Protection》 2022年第11期225-235,共11页
The intensification of anthropic uses (i.e., increase of the hemerobic condition) threatens the remnants of native vegetation due to the reduction of its self-regulation capacity. In this research, the Distance to Nat... The intensification of anthropic uses (i.e., increase of the hemerobic condition) threatens the remnants of native vegetation due to the reduction of its self-regulation capacity. In this research, the Distance to Nature (D2N) index for land use and land cover was applied in the Río Grande de Comitán watershed (Southern Mexico) to answer the following questions: 1) What were the land use dynamics observed in the Rio Grande de Comitán watershed in the trajectory through 1999, 2009 and 2019? 2) Does the subcategorization of the D2N allow one to identify which anthropic uses influence more the territorial expression of the watershed? To answer these questions, we performed a supervised classification of land use and land cover was performed in this watershed, and for the D2N index, the classification was simplified to three-category scale for the subcategorization of the anthropic component. Through Principal Component Analysis (PCA), we identified that agricultural anthropogenic use had the greatest influence on territorial expression. The reported scenario indicates a trend of gradual and continuous reduction of naturalness over the last 20 years. Additionally, the D2N index proved to be a useful tool to demonstrate both the anthropic impact, with the simplified scale, and the component that most influences the territory, by subcategorizing the anthropic scale. 展开更多
关键词 Anthropic land-Use Pressures SPATIO-TEMPORAL Principal Component Analysis (PCA) Environmental Planning nature Conservation
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Urban Planning Based on Nature—A Nature-Based Solution
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作者 Tomislav Đorđević 《Journal of Building Construction and Planning Research》 2023年第1期1-25,共25页
After an international contest announced by the City of Abu Dhabi “Cool Abu Dhabi Challenge”<sup>1</sup> and the article published as a digest of a paper titled A Nature-based Solution [1], the decision ... After an international contest announced by the City of Abu Dhabi “Cool Abu Dhabi Challenge”<sup>1</sup> and the article published as a digest of a paper titled A Nature-based Solution [1], the decision has been made to take part in improving thermal comfort in public spaces by mitigating the impact of the effect of Urban Heat Islands (UHI)<sup>2</sup> in the city of the Belgrade. The basic research aims at achieving the balance between the conflicting impacts when the buildings with their infrastructure and water-green surrounding area are in such correlation that it fulfils acceptable living and heating standards and reduces the use of fossil fuels for cooling the urban areas (buildings). By implementing the remote detection it is possible to analyze and quantify the impact of over-building on the temperature rise in urban areas as well as the disturbance of the heating comfort and the increased demand for additional cooling. Now it is possible to create virtual models that will incorporate this newly-added urban vegetation into urban plans, depending on the evaporation potential that will affect the microclimate of the urban area. Such natural cooling can be measured and adapted and hence aimed at a potential decrease in areas with UHI emissions [2]. Suitable greenery in the summer season can be a useful improvement which concurrently enables and complements several cooling mechanisms—evaporative cooling and evapotranspiration, i.e. natural cooling systems. The remote detection shall establish and map the “healthy” and “unhealthy” greenery zones—that is the vegetation zones with the highest evaporative potential with the “cooling by evaporation” effect and also, by implementing the urban prediction model, it shall propose green infrastructure corridors aimed at a potential decrease in the Urban Heat Island Emission. 展开更多
关键词 nature-Base Solution (NBS) Urban Heat Islands (UHI) land Surface Temperature (LST) land Use and land Cover (LULC) Normalized Difference Vegetation Index (NDVI)
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苍山洱海国家级自然保护区土地利用格局
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作者 胡昌平 姜健发 +2 位作者 王有兵 李亚楠 王生 《大理大学学报》 2024年第6期24-30,共7页
目的:了解云南苍山洱海国家级自然保护区(以下简称“保护区”)土地利用结构及特征,掌握土地利用的景观格局,为保护区整合优化及后期管理提供指导。方法:以相关调查数据为基础,基于GIS技术,对保护区土地利用现状、景观格局及矛盾冲突进... 目的:了解云南苍山洱海国家级自然保护区(以下简称“保护区”)土地利用结构及特征,掌握土地利用的景观格局,为保护区整合优化及后期管理提供指导。方法:以相关调查数据为基础,基于GIS技术,对保护区土地利用现状、景观格局及矛盾冲突进行分析。结果:苍山片区以林地和草地为主(面积占比96.43%),洱海片区以水体为主(面积占比98.02%);研究区域林地、水域和草地景观形状较为规整,景观破碎度较低,受人为干扰较少;保护区的景观多样性较丰富,但分布不均;保护区各类矛盾冲突图斑面积占保护区总面积的2.44%,矛盾冲突地块主要分布于缓冲区和实验区,以耕地和集体人工商品林为主,采矿用地、城镇建成区和村庄对保护区的影响程度最大。结论:保护区土地结构较为合理,苍山片区管理上要以森林防火、生物多样性保护、地质遗迹保护为主;洱海片区要以湿地保护,特别是水体质量维护和提升,以及水生动植物保护为主。 展开更多
关键词 土地利用 景观格局 矛盾冲突 苍山洱海国家级自然保护区
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国土“三调”赋能下的耕地恢复潜力调查研究
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作者 詹金瑞 邹玉学 《地理空间信息》 2024年第4期96-98,共3页
恢复类地块是耕地资源的重要储备,充分认清恢复类地块资源的数量及恢复耕地潜力,对保障国家粮食安全具有重要意义。本文全面介绍了耕地恢复潜力调查工作,并与耕地后备资源潜力调查模式进行了横向对比分析。基于“三调”基础数据,以广州... 恢复类地块是耕地资源的重要储备,充分认清恢复类地块资源的数量及恢复耕地潜力,对保障国家粮食安全具有重要意义。本文全面介绍了耕地恢复潜力调查工作,并与耕地后备资源潜力调查模式进行了横向对比分析。基于“三调”基础数据,以广州市从化区耕地恢复潜力调查为研究对象,采用“3+2”的分段调查模式。第一阶段以图斑为单元,依现状核实“农作物种植/水产养殖类别”、“耕作便利度”和“水源保障”三类属性信息;第二阶段以村社为单元,核实记录“恢复成本”和“群众意愿”两类属性信息;最后,从地块恢复成本、水源供给和耕地质量等条件,进一步对恢复类耕地开发利用的工作方向提出建议。 展开更多
关键词 自然资源 耕地恢复潜力 调查评价
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基于自然资源综合调查的城市环境品质分析
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作者 丁晶 吴辉 张婷 《工程勘察》 2024年第2期54-58,共5页
随着自然资源调查监测体系建设不断的推进,土地、森林、草原、湿地、海域海岛等调查数据逐步衔接融合,自然资源“一套底数”呼之欲出。如何利用数据开展综合应用分析,充分发挥调查监测数据的优势和价值,为自然资源管理工作提供科学依据... 随着自然资源调查监测体系建设不断的推进,土地、森林、草原、湿地、海域海岛等调查数据逐步衔接融合,自然资源“一套底数”呼之欲出。如何利用数据开展综合应用分析,充分发挥调查监测数据的优势和价值,为自然资源管理工作提供科学依据,已成为目前亟待解决的问题。本文基于研究区域调查数据成果,利用统计分析、空间分析等方法进行数据分类、分项统计,从国土空间规划和监督实施的角度,进行街道活力综合分析、社区生活圈可步性测度分析、社区生活圈分析和碳汇能力分析,为国土空间功能优化和品质提升提供有效的数据支撑。 展开更多
关键词 自然资源调查监测 街道活力 碳汇能力 国土空间功能优化
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