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1.
森林资源规划的目的是设计在一段时间内和在一定空间中的积极干预,通过权衡具有不同社会功能的森林价值,使得在某一特定区域的特定功能价值最大化。文中在查阅国内外森林资源规划研究的基础上,系统分析了国内外森林资源规划系统及模拟核心内容。森林资源规划系统越来越受到国内外专业森林经营管理机构的青睐,专业化森林规划软件在推动森林生态服务价值模型建立、林分空间优化、复杂约束条件和目标分析中起到了积极的作用。在全球气候变化大背景下,未来农田与森林将被作为一个有机整体,开发多尺度、多数据复合的森林规划平台。  相似文献   
2.
浙江省耕地多功能价值时空变化与权衡-协同关系   总被引:19,自引:14,他引:5  
耕地多功能价值的时空演变与权衡-协同关系测度对于深化耕地可持续利用和管理具有重要意义。该研究以经济快速发展地区浙江省为例,采用价值量化方法对2000、2010和2015年浙江省耕地多功能进行价值评估并分析其时空变化特征。运用Spearman秩相关系数法、双变量空间自相关模型以及可拓展随机性环境影响评估(StochasticImpactsby Regression on Population,Affluence and Technology,STIRPAT)模型探究耕地多功能之间的权衡-协同关系及影响因素。结果表明:1)2000—2015年浙江省耕地多功能总价值下降,地均耕地多功能价值呈现先下降后上升的趋势。其中气体调节、水源涵养和社会保障功能价值下降明显,食物生产和美学景观功能价值增加;耕地多功能总价值在空间上呈现北高南低的分布格局,2000—2015年大部分县市耕地多功能总价值均有不同程度的下降,西南山地丘陵区耕地多功能总价值有所提升。2)浙江省耕地多功能之间主要表现为协同关系,各项功能之间的协同-权衡关系存在空间异质性;2000—2015年,浙江省耕地多功能协同关系总体减弱,在空间上主要表现为高值协同区减少。3)城镇居民可支配收入和地均农业机械总动力对耕地多功能总价值有负面影响,农村居民可支配收入增加有助于耕地多功能总价值的提升。该研究成果可为科学划定耕地利用与保护区,促进耕地多功能的协同利用和提升耕地资源价值提供科学依据。  相似文献   
3.
东北黑土区是我国重要的生态功能区,也是主要的粮食产区,持续多年的开垦利用,加剧了该地区生态环境的恶化,因此探究黑土区生态系统服务的时空分异特征及协同权衡关系对该区域社会经济生态协调发展有重大意义。以宾县为研究区,综合利用InVEST模型、RUSLE模型、CASA模型、R语言和GeoDA软件,定量测度该县2000—2020年产水量、土壤保持和碳固定3种生态系统服务的时空格局及权衡与协同关系。结果表明:(1)从时间变化看,产水量呈上升趋势,碳固定和土壤保持呈先降低后上升的波动变化趋势;(2)从空间分布看,产水服务高值区表现为由中部向四周递减的趋势,碳固定和土壤保持服务总体呈现为南高、东低的空间分布格局。(3)权衡协同关系表明,2000—2020年,协同关系是宾县生态系统服务间的主导关系; 数值上,3种生态系统服务的协同关系持续增强,具体表现在相关系数和Moran's I指数的增加; 空间上,正、负相关集聚性明显,权衡协同关系分布空间分异性显著。综上,宾县生态系统服务变化呈上升趋势,南部区域生态系统服务较强,未来应在空间上促进生态系统服务协同发展。  相似文献   
4.
Stand-level tree diameter growth patterns were explored for evergreen moist forests in the southern Cape, South Africa. Results of standard multiple regression analyses, involving 934 permanent sample plots with data spanning a 10-year interval, revealed that stand-level increment of canopy species in the canopy layer (>30 cm dbh) was significantly determined by inherent species-specific growth capacities (species composition of the stand), water availability, forest matrix crowding and tree condition impairment (age-related manifestations of reduced vitality indicated by signs of crown die-back, damage and stem rot). In contrast, stand-level increment of trees of canopy species in the subcanopy layer (10-20 cm dbh) was prominently shaped by light availability, as mainly determined by the degree of canopy-level disturbance (mortality rate of trees >30 cm dbh), crowding (canopy-level overhead and forest matrix crowding) and proximity to conspecific adults (within 6-8 m). In addition to species-inherent and resource factors, considerable variation in stand-level growth resulted from site-climate interactions. For 507 of the permanent sample plots, increment data was available for two consecutive 10-year intervals; permitting the analysis of spatiotemporal interactions of growth patterns (repeated measures ANOVA). In the Knysna forests higher canopy-level increment rates were associated with the moister southerly facing slope sites in comparison with the drier northerly facing and ridge sites during the first increment period. During the second increment period, increment rates on the drier, but better illuminated sites had increased disproportionately. In contrast, in the Tsitsikamma forests, higher increment rates during the second increment period were encountered on moister flat bottomland sites (with extended periods of subsoil wetness) than on the comparatively drier southerly facing slope sites (increment period × site-based water availability × forests interaction). In both forests relatively higher growth performance of subcanopy-level trees during the second increment period was associated with stands experiencing conditions of enhanced light availability. Atmospheric temperatures were higher during the second increment period (mean periodic Tmax: + 0.64 °C). The detected spatiotemporal interactions were interpreted as site × climate interactions where site-related conditions of favourable light or water availability resulted in enhanced temperature-linked growth responses during the second increment period. A metabolic performance trade-off model provided a framework for the interpretation of these complex site-climate interactions by placing the patterns of forest growth into an ecophysiological explanatory context.  相似文献   
5.
探析生态系统服务的变化特征及其权衡与协同关系,为制定生态环境保护政策和区域发展规划提供决策参考。利用1990—2018年4期土地利用数据,运用当量因子法、GIS空间分析与地理探测器模型,基于格网尺度刻画安徽省生态系统服务价值(Ecosystem Service Values, ESV)时空演变特征和权衡/协同关系,探讨了影响ESV空间分异的主要因素及其交互作用。结果表明:(1)在1990—2018年期间安徽省ESV呈不断减少趋势,从研究初期的3 647.37亿元(1990年)减少至3 567.78亿元(2018年),下降了79.59亿元。(2)空间尺度上,ESV空间分布格局变化较小,空间异质性明显,呈现明显的南高北低的空间分异特征。(3)数值关系上,4种典型生态系统服务之间呈现不同强度的协同关系。空间分布上,生态系统服务的空间权衡/协同表现出显著的分异特征,一对生态系统服务的权衡与协同关系因空间尺度不同而存在一定差异。(4)县域尺度ESV空间分异格局是多种因素综合作用的结果,其中人口密度和人为影响综合指数对区域ESV空间差异的决定力显著强于其他因素。两两驱动因子交互作用对ESV的影响力...  相似文献   
6.
朱俊俊    高周冰    王君櫹    廖凯华  吕立刚   《水土保持研究》2023,30(3):383-394
[目的]全面理解生态系统服务的时空格局特征及其相互关系,可以丰富生态系统服务及可持续发展等相关理论,并对区域生态环境管理政策的制定具有重要指导意义。[方法]以南京都市圈为研究区,在评估2000—2020年的产水、粮食供给、土壤保持和碳固持等4种生态系统服务的基础上,分析各类型生态系统服务能力在地类和区域上的差异;通过识别生态系统服务热点区及其热点服务类型,评估不同区域服务供给能力;进而采用相关系数和差异比较等方法探究南京都市圈生态系统服务静态与动态的权衡/协同关系。[结果]2000年、2010年、2020年,南京都市圈的产水量、粮食产量、土壤保持量及碳固持量的三年平均值分别为522.12 mm, 4.20 t/hm2,42.61 t/hm2,44.57 t/hm2,除碳固持服务逐年下降,其他服务均呈逐年递增趋势。受土地利用类型和区域自然环境的作用,产水、土壤保持和碳固持服务呈南高北低的空间分布,粮食供给服务则呈南低北高的空间格局。由北向南依次形成了以粮食供给服务为主的1重服务热点区、以产水和粮食供给服务为主的2重服务热点...  相似文献   
7.
Knowledge of herbivory tolerance of dominant plant species and their responses to varying grazing intensity is required for sustainable grazing management in semiarid rangeland ecosystems. In a field experiment, we studied the effects of simulated grazing 0%, 30%, 50%, and 80% leaf removal (control, partial, intermediate, and heavy leaf removal) of three dominant perennial legumes: Astragalus cyclophyllon, Astragalus effuses, and Hedysarum criniferum in semiarid rangelands of southwestern Iran for 2 yr and tested 1) differential herbivory tolerance in terms of regrowth ability of belowground and aboveground biomass (AGB), fecundity, and nonstructural carbohydrate reserves; and 2) trade-off between forage quantity and quality—less defoliated plants produce larger amount of biomass with less forage quality and vice versa. The results showed a reduction in AGB and reproduction in each of the three plants. However, three forbs exhibited some sort of variations in shoot and root growth, reproduction and forage quality under intermediate and heavy leaf removal. Leaf removal in individuals of A. effusus and H. criniferum are more likely to compensate for tissue loss by allocating the available resources to the expansion of root biomass, at the cost of AGB and reproductive effort. Leaf removal also led to an increase in forage quality in each of the three forb species, depending on the level of height removal. The control plant had a higher amount of biomass production and lower amount of crude protein compared with heavy leaf removal treatments (i.e., 80%), by contrasting responses of acid detergent fiber and neutral detergent fiber, indicating a trade-off between forage quality and forage quantity. The results indicate that there is a balance among forage quantity, quality, and regrowth ability of belowground and aboveground tissues in intermediate leaf removal treatments of these forb species. This balance is used to develop principles for grazing management of steppe rangelands because such a regime meets different criteria including forage quantity, quality, and nonstructural carbohydrate reserves.  相似文献   
8.
This paper provides an example of the practical application of multi-attribute trade-off analysis (MATA) to wildfire management. The MATA approach supports more informed decision-making because it exposes important trade-offs among competing management objectives (requiring value-based choices), helps guide and structure necessary technical judgements, explicitly represents uncertainty (i.e., not just expected outcomes but risk profiles around outcomes) and addresses temporal trade-offs. MATA promotes critical thinking about what analysis is required for decision-making. A MATA approach can be applied for all types of forest and fire management decisions. In this paper, we provide a sample application of MATA to an evaluation of landscape-level fuel treatments for managing wildfire risk. The study area is located in southeastern British Columbia, Canada where historical fire suppression policies and expanding development in wildland urban interface areas have resulted in an increase in both the probability and the consequences of stand replacement fires. We specify management objectives and develop measurable attributes for fire management costs, timber supply, property damage, landscape-level biodiversity, local air quality and climate change. We then simulate the effects on these attributes of four alternative fuel management strategies that include combinations of mechanical treatments and prescribed burning over a 100-year period. The evaluation illustrates the key features of MATA while highlighting the benefits and challenges of implementing the approach.  相似文献   
9.
安庆都市圈生态系统服务权衡与协同   总被引:1,自引:0,他引:1  
为厘清区域发展特征、优化区域布局、实现生态转型和绿色可持续发展,研究生态系统服务之间的权衡和协同关系是发展的基础.本研究以安庆都市圈为研究对象,运用空间计量法估算安庆都市圈的水源涵养、土壤保持、NPP服务和食物供给等4种生态系统服务,分析不同生态系统服务之间的权衡与协同关系,并运用CA-Markov模型预测203 0年...  相似文献   
10.
谢晓欣  吴宇哲 《安徽农业科学》2011,39(36):22658-22660
以浙江省缙云县为研究案例,以农居点整理为切入点,从潜力、经济、生态3个方面系统分析了城乡建设用地总规模控制实行的可能性。研究表明,缙云县存在农村居民点整理潜力不足、整理资金约束大、农村居民点整理对生态环境潜在的负面影响较大等问题,增加了城乡建设用地总规模控制目标实现的难度。在此基础上,提出了控制城乡建设用地总规模的政策建议,即应从转变政府规划理念、合理建设工业园区、完善土地征收制度、合理选择整理模式、保障农民切身权益等5个方面配合农村居民点整理综合实施。  相似文献   
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