首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
马世发  劳春华  江海燕 《生态学报》2021,41(9):3441-3448
国土空间生态修复分区有助于推动生态修复工作的整体性和系统性。利用国土空间生态安全格局理论进行生态修复分区是一种较为经典的模式,但现有分区技术方案对高强度人类活动导致的土地利用景观变化考虑不足,不能很好的适应城市群尺度国土空间生态安全格局的塑造需求。设计了一种基于情景模拟的国土空间生态修复分区方案,该框架首先通过耦合空间马尔科夫链与元胞自动机模型模拟城镇化发展末期的土地利用景观格局;然后利用"生态源地-生态廊道-生态网络"理论构建国土空间生态安全格局基本骨架;最后根据最小累积阻力模型划分出生态修复关键区、调节区和双修区等类型。粤港澳大湾区案例研究表明:(1)土地利用景观变化对生态修复分区方案影响较大,不同景观格局导致的分区规模差异可达国土空间的10%左右;(2)国土空间生态修复分区需要充分考虑高强度人类活动对景观格局变化的潜在影响,进而使得生态修复分区政策更有利于国土空间生态安全格局塑造目标的实现。研究构建的国土空间生态修复分区技术方案可进一步深化生态安全格局理论在国土空间规划应用上的认知。  相似文献   

2.
In situ phosphorus release rates in three contiguous shallow brackish lakes were calculated by considering the amount of water inflow, changes in salinity and phosphorus stock, and loading from phosphorus inflow based on monthly data. The annual amount of sedimental phosphorus relative to that of phosphorus inflow was different for each of the three water bodies: 16% for Lake Shinji, 3% for the Honjo area, and −8% for Lake Nakaumi, as estimated in a 10-year period from January 1993 to December 2002. During the warm season, the quantity of phosphorus released surpassed sedimentation in these three water bodies. The low annual sedimentation ratio in Lake Nakaumi is related to a large seawater backflow resulting in phosphorus removal, in addition to a stable stratified structure promoting phosphorus release from sediment due to oxygen depletion in the lower layer. In Lake Nakaumi, field data shows that if dissolved oxygen at the sediment surface falls below 2.54 mg L−1, phosphorus release from the sediment begins to be accelerated.  相似文献   

3.
土地利用变化是生物多样性与生态系统服务变化的主要原因之一。评估土地利用变化对生物多样与生态系统服务影响对于政府决策具有重要作用。钱江源国家公园体制试点区是钱塘江的源头, 也是国家的重点生态功能区。本研究以钱江源国家公园体制试点区为研究区, 首先设计自然发展情景、规划情景、生态保护情景和开发利用情景等4种2025年不同土地利用变化情景, 随后采用InVEST模型和CLUE-S模型分析不同情景下钱江源国家公园水资源供给、涵养水源、固碳释氧、土壤保持、环境净化和生境质量等生态系统服务及其价值变化。结果表明: (1)核心保护区和生态保育区的生态系统服务价值占钱江源国家公园总价值的88.30%。(2)生态保护情景下钱江源国家公园生态系统服务价值最高, 有129.17亿元; 规划情景下生态系统服务价值次之, 有126.92亿元。(3)规划情景下钱江源国家公园水资源供给服务优于生态保护情景, 其他生态系统服务则次于生态保护情景。考虑到钱江源国家公园为下游提供重要的水资源这一功能, 将规划情景作为试点区2025年最优的土地利用变化情景。  相似文献   

4.
生态弹性是森林生态系统在遭受外在扰动后恢复到稳定状态的能力,是森林资源可持续发展的重要目标之一,且森林生态弹性对诸如气候变化、林火和营林措施等外部因子的影响较为敏感.探究这些外部因子对森林生态弹性的影响在未来森林生态系统管理方面有重要意义.本研究首先从森林组成、结构和功能等方面选取指标因子并估算了森林生态弹性值,然后运用LANDIS PRO模型,模拟气候变化、林火干扰和营林措施等对寒温带典型森林生态弹性的影响,并探讨了当前抚育采伐方案在未来气候下的可持续性.结果表明: 模型初始化的2000年林分密度和胸高断面积与2000年真实景观较为吻合,模拟的2010年森林景观与野外调查数据无明显差异,基于当前林火干扰状况的模拟结果与火烧迹地调查数据基本匹配,说明林火模块能很好地模拟当前研究区林火发生状况.林火干扰增加30%将会使该区模拟期内景观水平上森林生态弹性提高15.7%~40.8%,而林火干扰增加200%则会降低该区4.4%~24.6%的森林生态弹性.短期和中期林火干扰增加对森林生态弹性的影响大于气候变化的影响.与当前预案相比,B1气候(林火增加30%预案)和A2气候(林火增加200%预案)对整个模拟阶段景观尺度森林生态弹性的影响分别处于-15.9%~38.9%和-60.4%~34.8%范围内.与无采伐预案相比,B1和A2气候下在整个模拟时期内若继续实施当前抚育采伐方案,将不利于景观水平森林生态弹性的提高.在B1气候(林火增加30%预案)下,在各模拟时期内无需实施任何营林措施;而在A2气候(林火增加200%预案)下,建议实施中、高强度种植的营林措施以提升景观水平森林生态弹性.  相似文献   

5.
厦门海湾型城市发展累积生态效应动态评价   总被引:4,自引:0,他引:4  
港湾地区的快速城市化使港湾湿地生态系统及其生产功能和服务功能发生急剧改变并在时间和空间上产生累积效应。以具有典型意义的厦门港湾湿地为研究对象,采用系统动力学方法,定性分析系统因子因果反馈关系,筛选港湾湿地水动力环境、水质环境、生物生态环境、地形地貌、景观环境作为厦门海湾型城市发展的累积生态效应指示因子。通过调整模型的相关政策变量及组合,仿真模拟了不同发展策略下厦门港湾湿地的累积生态效应,并结合灰色评估模型对累积生态效应进行量化,得出不同发展策略的累积生态效应指数,并对模型进行了模型验证与敏感性分析。设计三大未来发展情景,即基准情景(BS)、发展规划情景(S1)、生态城市发展情景(S2)。模型模拟结果表明:基准情景下2020年厦门城市发展对港湾湿地的累积生态效应指数为0.61;发展规划情景下对港湾湿地的累积生态效应指数为0.37;生态城市发展情景下对港湾湿地的累积生态效应指数为0.30,相对基准情景下可减少累积生态效应50%,建议厦门市按照海湾型生态城市模式进行发展。  相似文献   

6.
Local oxygen lack in arterial walls (hypoxia) plays a very important role in the initiation, progression and development of intimal hyperplasia (IH) and thrombosis. Aiming to find out whether a helical-type artery bypass graft (ABG) is hypoxia beneficial, a numerical study was carried out to compare oxygen transport between a helical-type ABG and a conventional-type ABG. The dimensionless mass transfer coefficient (Sherwood number) was introduced to evaluate the oxygen mass transfer distribution and detailed oxygen wall flux was computed. The results show that the intrinsic geometry of a helical-type ABG resulted in improved hypoxia and the oxygen-depleted fluid located proximally to the occluded section as compared with that of a conventional-type ABG. However, benefits aside, distinct double low regions (low wall shear stress (WSS) and hypoxia) which might be most prone to IH and more localised and thicker boundary layer of oxygen-depleted fluid were observed at the helical-type ABG. This may explain why the helical flow plays a detrimental role at some locations in the human body. In addition, it was observed that although low WSS region was always accompanied with low oxygen supply, the oxygen transport rate did not adjust simultaneously with flow. The change in oxygen distribution usually lagged behind the flow change. A physiological WSS region may be associated with hypoxia condition. This study captured the qualitative trend of oxygen distribution in ABGs and the effect of helical geometry on reducing hypoxia, which is useful in the structural design of swirling flow vascular devices.  相似文献   

7.
王盛  李亚文  李庆  胡世雄  王金凤  李文静 《生态学报》2022,42(13):5391-5403
张家口-承德地区是京津冀环境优化的战略要地,开展水源涵养和土壤保持服务的定量评估对维护生态系统的安全运行意义重大。综合运用InVEST模型、空间偏相关统计制图及情景模拟等手段,分析了张承地区近20年水源涵养和土壤保持服务的时空变化特征及其复杂空间关系,定量评估二者对气候和土地利用变化的响应。结果表明:2000-2019年张承地区水源涵养量、土壤保持强度分别以0.97mm/a的速率增加和-0.50t hm-2 a-1的速率减少,空间上二者均呈西低(坝上高原)东高(冀北及燕山山地)的分布格局。冀北及燕山山地落叶阔叶林生态区水源涵养和土壤保持能力强,二者空间关系以协同为主;坝上高原草原与农业生态区则权衡关系更占优势。水源涵养和土壤保持服务关系复杂,空间上与区域土地利用类型、植被覆盖度和坡度关系密切。情景模拟结果表明,降水(r=0.90,P<0.01)对水源涵养服务的影响远大于潜在蒸散(r=-0.37,P>0.1),且降水变幅越大对水源涵养量的作用越强;而降水变化与土壤保持服务呈线性正相关关系,降水每增加(减少)10%引起土壤保持强度增加(减少)74.7t/hm2。预计2030年张承地区水源涵养能力将明显提升,土壤保持能力变化不大,届时人为干扰(如生态保护、规划控制)将对提升水源涵养服务产生重要影响。为改善张承地区水源涵养和土壤保持服务,需同时考虑多种因素的综合影响,以制定更合理的政策措施。建议继续加大国家重点生态工程建设,尽可能限制建设用地扩张,提高植被覆盖度,尤其加强保护关键坡度带是今后生态管理工作应关注的重点。  相似文献   

8.
A response in movement of a two-layered water body in Lake Nakaumi to a strong wind, which suddenly rose and continued for 15 h with nearly constant speed and direction, was observed using the current and salinity meters situated at two points in the lake. At the initial stage of water movement, large fluctuations in current velocity in reverse directions were observed in the upper and lower layers, accompanied by mixing between the two layers. At the stationary stage following the initial stage, current velocities in the upper and lower layers were kept constant, as was salinity. It was considered that a slab-type flow, which enhanced mixing between the two layers, occurred at the initial stage in water movement, then changed into a steady circulation flow at the stationary stage with completion of the set up in the two-layered structure. Received: July 3, 2000 / Accepted: February 8, 2001  相似文献   

9.
A coupled three-dimensional physical-biological model was developed in order to simulate the ecological functioning and potential impacts of land-derived inputs in the southwest lagoon of New Caledonia. This model considered pelagic biogeochemical cycling of organic matter, taking into account advection and diffusion processes driven mainly by local wind fields and freshwater discharges. Modeled phytoplankton dynamics were strongly correlated with both freshwater nutrient inputs and wind-driven hydrodynamic processes, the latter resulting in a large input of oceanic water from the southeast part of the lagoon under trade wind conditions. In situ data obtained during the summer (January 1998) under trade wind conditions supported predicted concentration gradients along several coast to reef transects and provided a validation of the coupled physical-biogeochemical model. An additional sensitivity analysis showed that the alteration of the biogeochemical parameters did not strongly affect the results of the model. Freshwater inputs of nutrients were simulated using a realistic scenario corresponding to the summer rainy season of 1997–1998 in New Caledonia. Despite occasional flooding events from the main rivers considered in these simulations, no significant meso-scale phytoplankton bloom was identified. Hydrodynamically driven dispersion and rapid uptake of nutrients by phytoplankton were sufficient to spatially constrain the impact of river inputs and maintain oligotrophic conditions. The fine spatial grid of our three-dimensional model demonstrated that eutrophication in the southwest lagoon of New Caledonia is confined to the most restricted coastal embayments, while most of the lagoon experiences sustained oligotrophic conditions.  相似文献   

10.
赵素芹  孙翔  侯东林  朱燚 《生态学报》2020,40(10):3247-3257
生态补偿标准研究是国内外流域生态补偿领域研究的热点话题。以国家生态补偿试点区九洲江流域为例,围绕生猪养殖跨界污染问题,以COD、TP、TN为目标控制污染物,计算水环境容量约束下的污染物削减目标量。设置禁养区关闭拆迁养猪场、高架床养殖模式改造、养殖粪尿废水集中处理3种典型控制方式,以污染物削减目标量为约束条件,构建线性规划模型求算不同治理情景下用于水污染控制的投入成本,从而求算最小生态补偿量。在此基础上以取水量、供水量、GDP为主要约束条件,建立中央、广东、广西政府生态补偿投入资金分担比例模型,明确中央、广东及广西政府各自分摊的生态补偿金额。此外,考虑到模型参数不确定性对生态补偿量的影响,对模型参数进行了蒙特卡罗模拟和灵敏度检验,求算高架床养殖容积比(k1)、限养区污水入河系数(k2)、高架床养殖模式日排水量(k3)及传统养殖模式日排水量(k4)不确定条件下生态补偿量的所有可能值及模型参数方差贡献率。结果显示:(1)在90%保证率水质达标下,流域水环境COD、TP、TN污染物削减总量目标分别为378752.98 t、2161.60 t和13951.70 t;(2)基于成本核算法得到生态补...  相似文献   

11.
Primary production and decomposition of organic substances were investigated in a tropical lagoon during the rainy season. Production and mineralization were measured using the oxygen method. Total bacteria numbers and biomasses were estimated with epifluorescence microscopy, and the enzymatic degradation capacity of model substrates was determined photometrically. These parameters were measured in the water and sediment of the lagoon itself and also in its effluents and incoming waters. The aim of the study was to determine the sites of highest microbial activity in the lagoon and to compare its activity with other coastal water bodies. Since the shallow water lagoon contains a large amount of particulate matter, it was of special interest to study the degradation of this material and its influence on the microbial population. It was found that up to 14 % of the bacteria colonized the particles and that 62 % of the respiration originated in the particle fraction >8 μm. Highest exoenzymatic activities were measured in the sediment and water of the mangrove belt. It is concluded that decomposition and conditioning of particulate organic matter play dominant roles in the recycling of organic carbon in the lagoon.  相似文献   

12.
This paper investigated the spatio-temporal variability of water quality parameters (transparency, salinity, dissolved oxygen, nutrients viz. NH3-N, NO2-N, NO3-N, PO43-P, total nitrogen, total phosphorous and chlorophyll-a) in Chilika lagoon during 2001–2003 in order to better understand its ecological characteristics. Marked spatial and seasonal variations were detected with respect to almost all parameters studied. Northern sector of the lagoon is more affected by the anthropogenic stress from the catchments than the southern sector. Addition of nitrogen and phosphorous compounds to the lagoon mainly occurred through the drainage from agricultural lands and river run off during the early months of paddy cultivating seasons. Phytoplankton productivity of the lagoon was nitrogen limited, as suggested by nitrogen to phosphorous ratio. Processes affecting the water quality of the lagoon system included agricultural drainage, sewage intrusion, macrophyte litter fall and exchange of water between lagoon and the sea (Bay of Bengal). Further in depth study pertaining to quantification of exogenous material input and their disposal is recommended to ensure proper management of the lagoon and its resources.  相似文献   

13.
Anoxia constitutes an important environmental problem, affecting coastal systems around the world. The physicochemical alterations on the water column of anoxic basins, caused by morphological modifications, were studied.Deepening on the connecting sill between the permanent anoxic Aitoliko lagoon and Messolonghi lagoon was accomplished on May 2006. Seasonal variations of parameters like temperature, salinity and dissolved oxygen along the lagoon's water column were recorded and studied in a net of 14 stations, after sill's dredging. Wind speed and wind direction time series were used to estimate the wind's contribution to the hydrographical changes.The water fluxes between the two environments increased, due to the sill's cross section increase. Salty water inflow into Aitoliko lagoon was recorded during the sampling period and was correlated with monimolimnion oxygenation throughout winter months. The meteorological conditions that prevailed during the sampling period could not create strong water inflows into the Aitoliko lagoon, and consequently it was not the reason for the recorded alterations in the lagoon's water body anoxia.The limited deepening of the sill created a mild increase of water flow into the anoxic lagoon. This inflow of the saltier water resulted in a weak mixing of the water column, introducing oxygen into the bottom water for the first time in 55 years, without destroying the stratification.  相似文献   

14.
This work was carried out in a shallow eutrophic coastal lagoon (St. André lagoon, SW Portugal) which is artificially opened to the sea each year in early spring. Macrophytes, mainly Ruppia cirrhosa, are keystone species in this ecosystem covering up to 60% of its total area with peak biomasses over 500 g DW m–2. The main objectives were to study ecosystem metabolism, to evaluate the metabolic contribution to the community of the macrophyte stands and their influence in the development of thermal stratification and bottom oxygen depletion.The work combined an experimental and a modelling methodology. The experimental approach included open water, mesocosm and microcosm seasonal experiments. During these experiments several physical, chemical and biological parameters were monitored in the lagoon and in plastic enclosures (mesocosms) for periods of 24 hours. The microcosm experiments followed the light-dark bottle technique. The simultaneous use of these different methodologies allowed the analysis of the contribution of the planktonic and benthic compartments to the ecosystem's oxygen budget.The modelling work was based on the mathematical simulation of heat and gas exchanges in a vertically resolved water column, under different macrophyte densities. Several simulations were carried out, in order to investigate the importance of the macrophytes in the development of water column stratification and anoxia.The simulation results suggest that macrophytes may greatly influence thermocline and oxycline development. This influence is proportional to their biomass and canopy height. It is suggested that controlled macrophyte biomass removal of up to 25% of available biomass in summer, may be useful in preventing bottom anoxia without compromising benthic net primary production.  相似文献   

15.
刘洋  韩雯颖  孙志贤  桑国庆 《生态学报》2024,44(10):4129-4141
洪涝灾害情景模拟与损失预估对湖泊型流域防洪减灾和可持续发展具有重要意义。以我国典型的湖泊型流域南四湖流域为例,利用CA-Markov模型预测2030年三种用地情景,采用P-III型概率曲线构建10、20、50、100 a四个重现期强降雨情景,得到12种组合情景;通过InVEST模型和等体积淹没法量化不同情景的径流和淹没深度;在各产业GDP空间预测的基础上计算12种情景的洪涝直接经济损失。结果表明:(1) CA-Markov模型在南四湖流域的土地利用模拟精度较高,三种用地情景的各地类变化显著;(2)用地变化对流域洪涝灾害的影响显著,其中城镇发展情景下洪涝灾害风险最大,而生态保护情景风险最低;(3)暴雨强度会明显增加各用地情景的经济损失,但增幅在50 a重现期后有所减缓;生态保护情景的经济损失最少,介于97.39-128.81亿元之间,与其他情景相比,该情景可在一定程度上减少洪灾损失。为此,在气候变化背景下湖泊型流域可持续发展应充分考虑土地利用变化对洪涝灾害风险的影响,合理扩张城镇建设用地,优化布局生态用地,充分发挥国土空间规划在防洪减灾方面的作用。  相似文献   

16.
土地利用变化将改变区域生态系统服务的稳定供给能力,进而对区域生态稳定和可持续发展构成威胁。中国西部地区快速城镇化背景下,扩张的经济发展需求对土地利用变化产生了重大影响。以丝绸之路经济带规划的重要节点城市张掖市为例,基于土地利用变化均衡分析(CGELUC)模型及土地利用动态模拟(DLS)模型,模拟了多情景下张掖市2010-2030年的土地利用变化时空分异特征,并通过生态系统服务价值(ESV)估算、空间自相关分析等方法分析并预测了ESV及其时空演变特征,集中分析了多情景下2030年张掖市ESV各项服务间的权衡与协同关系。结果表明:(1)2010-2030年张掖市土地利用格局变化显著,建设开发情景下城镇建设用地扩张最为剧烈,建设用地增长7.41%,耕地面积减少11.05%;生态保护情景下城镇扩张最为和缓,同时未利用地减少明显,面积降低1088km2,主要向林地、草地、水域等生态用地发生转化。(2)2010-2030年张掖市ESV在基准情景和生态保护情景下分别增长6.43、13.16亿元,建设开发情景则整体仅增加1.53亿元。(3)供给、调节、支持与文化4种单项ESV,基准和生态保护情景下均呈现显著上升趋势;建设开发情景下有3项呈现缓慢的增长趋势,且该情景下供给服务则始终呈现下降趋势。(4)各单项生态系统服务协同关系明显,东南-西北轴线南北两侧区域表现为协同关系,仅有少数区域表现为权衡关系,且供给-文化服务的权衡关系较为明显。本研究可为西部城镇化快速发展地区统筹经济发展与生态保护提供科学方案。  相似文献   

17.
Water level fluctuations in lakes lead to shoreline displacement. The seasonality of flooding or beaching of the littoral area affects nutrient cycling, redox gradients in sediments, and life cycles of aquatic organisms. Despite the ecological importance of water level fluctuations, we still lack a method that assesses water levels in the context of hydropower operations. Water levels in reservoirs are influenced by the operator of a hydropower plant, who discharges water through the turbines or stores water in the reservoir, in a fashion that maximizes profit. This rationale governs the seasonal operation scheme and hence determines the water levels within the boundaries of the reservoir''s water balance. For progress towards a sustainable development of hydropower, the benefits of this form of electricity generation have to be weighed against the possible detrimental effects of the anthropogenic water level fluctuations. We developed a hydro-economic model that combines an economic optimization function with hydrological estimators of the water balance of a reservoir. Applying this model allowed us to accurately predict water level fluctuations in a reservoir. The hydro-economic model also allowed for scenario calculation of how water levels change with climate change scenarios and with a change in operating scheme of the reservoir (increase in turbine capacity). Further model development will enable the consideration of a variety of additional parameters, such as water withdrawal for irrigation, drinking water supply, or altered energy policies. This advances our ability to sustainably manage water resources that must meet both economic and environmental demands.  相似文献   

18.
P. H. Nienhuis 《Hydrobiologia》2006,565(1):261-275
Over the past 50 years ecology has developed into a mature branch of the natural sciences, comprising firm concepts (e.g. for rivers River Continuum Concept and Flood Pulse Concept) and extensive empirical surveys (sophisticated lab and field experiments, simulation models, GIS). Estuaries and rivers are continuously threatened ecosystems, considering the massive expansion of man’s economic activities. I focus on rivers and estuaries in the Netherlands (W. Europe), where recent public interest has mainly been determined by two flooding disasters (mega-disaster in 1953; near-disaster in 1995). The measures taken to enhance the safety of the human population were adequate: building of large closure dams, and storm surge barriers in the estuaries, and heightening of levees along the rivers. Eventually these measures were detrimental for what was left of the dynamic river ecosystems from the past. This paper focuses on two ecosystem studies. (1) An ecosystem study in Grevelingen lagoon, a large embanked estuary that changed into a brackish water lagoon. Predictive ecological models (e.g. for the wax and wane of Eelgrass, Zostera marina) were inadequate because of the exceptional characteristics of the lagoon: the ecosystem appeared to be instable, and not resilient. (2) An ecosystem study at Afferdensche and Deestsche Waarden, a floodplain area along the river Waal, strongly affected by toxicants deposited before 1980. We studied the functioning and eco-toxicology of floodplain food webs, deteriorated by pollutants. Fine-tuned spatial components were introduced in ecological risk assessment models of several trophic levels (e.g. a top predator, the Little Owl, Athena noctua). Safety for the human population, living below sea level, and below the level of the main rivers, must be improved, but overhasty technocratic measures deteriorating the remaining semi-natural, highly appreciated landscapes, should be avoided. Stakeholder interests must be adapted to sustainable ecological river management, and not the other way round, as has been done for the past ten centuries.  相似文献   

19.
生物多样性和生态系统服务情景模拟是指对未来生物多样性和生态系统服务变化轨迹的定量估计,二者相互关联并为长期、稳定的保护和恢复生态系统提供了重要科学依据。梳理生物多样性以及生态系统服务预测情景的核心观点,讨论基于生物多样性和生态系统服务情景模拟的保护决策支持途径,以期服务于我国生物多样性与生态系统服务预测研究的发展和深化。研究凝练结果如下:物种分布模型需要进行更规范的评价以明晰其对具体对象的适用性,生态系统预测模型亟待在关系结构的基础上嵌入更多的生态系统过程和社会经济过程,生态系统服务评估模型有必要强化对生物多样性、生态系统服务、人类福祉级联特征的刻画;全球气候变化驱动了未来区域生物多样性的大幅改变;土地利用则是陆地生态系统服务预测中的核心驱动变量。生态区划与区域尺度情景模拟、景观尺度下的生态安全格局构建、基于社会生态网络的社区适应三点重要展望方向将对基于情景模拟的我国生态系统保护决策提供重要的理论和实践支持。  相似文献   

20.
薛智超  甄霖  闫慧敏 《生态学报》2023,43(15):6081-6098
黄土高原丘陵沟壑区生态环境脆弱,近几十年生态保护工程的实施带来显著的生态恢复效果,也对农户的生计策略与区域粮食安全产生了影响。刻画生态脆弱区人-地系统复杂响应过程,可以为区域可持续的土地利用管理模式提供依据。研究从土地多功能出发,着眼于黄土丘陵沟壑区河谷川地、梁峁区域、黄土塬地、土石山地以及城郊区域等不同的典型地貌类型与代表区域,采用多层次利益相关者参与式的评估框架,以农户的耕地利用行为及生态工程影响与未来发展为切入点,设置惯性发展情景、发展优先兼顾生态情景、农业优先兼顾生态情景以及生态优先兼顾发展情景,构建多智能体模型对区域土地利用与土地多功能的时空变化开展模拟。主要结果表明:(1)生态优先兼顾发展情景综合影响最高且对各维度影响相对均衡,而农业优先兼顾生态情景对区域土地的经济维度的功能和社会维度具有更为明显的提升效应;(2)根据土地多功能空间变化模拟结果,区域土地利用破碎化明显且耕地的撂荒对全域土地多功能均表现出明显的限制作用,农业优先兼顾生态情景中土地功能发生下降的面积最少;(3)发生土地功能下降的区域主要分布在土地质量较差、坡度处于5—15°范围内、地形起伏度较大以及距离道路较远...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号