985 resultados para Landscape planning


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Bottlenose dolphins (Tursiops truncatus) inhabit estuarine waters near Charleston, South Carolina (SC) feeding, nursing and socializing. While in these waters, dolphins are exposed to multiple direct and indirect threats such as anthropogenic impacts (egs. harassment with boat traffic and entanglements in fishing gear) and environmental degradation. Bottlenose dolphins are protected under the Marine Mammal Protection Act of 1972. Over the years, the percentage of strandings in the estuaries has increased in South Carolina and, specifically, recent stranding data shows an increase in strandings occurring in Charleston, SC near areas of residential development. During the same timeframe, Charleston experienced a shift in human population towards the coastline. These two trends, rise in estuarine dolphin strandings and shift in human population, have raised questions on whether the increase in strandings is a result of more detectable strandings being reported, or a true increase in stranding events. Using GIS, the trends in strandings were compared to residential growth, boat permits, fishing permits, and dock permits in Charleston County from 1994-2009. A simple linear regression analysis was performed to determine if there were any significant relationships between strandings, boat permits, commercial fishing permits, and crabpot permits. The results of this analysis show the stranding trend moves toward Charleston Harbor and adjacent rivers over time which suggests the increase in strandings is related to the strandings becoming more detectable. The statistical analysis shows that the factors that cause human interaction strandings such as boats, commercial fishing, and crabpot line entanglements are not significantly related to strandings further supporting the hypothesis that the increase in strandings are due to increased observations on the water as human coastal population increases and are not a natural phenomenon. This study has local and potentially regional marine spatial planning implications to protect coastal natural resources, such as the bottlenose dolphin, while balancing coastal development.

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Land-based pollution is commonly identified as a major contributor to the observed deterioration of shallow-water coral reef ecosystem health. Human activity on the coastal landscape often induces nutrient enrichment, hypoxia, harmful algal blooms, toxic contamination and other stressors that have degraded the quality of coastal waters. Coral reef ecosystems throughout Puerto Rico, including Jobos Bay, are under threat from coastal land uses such as urban development, industry and agriculture. The objectives of this report were two-fold: 1. To identify potentially harmful land use activities to the benthic habitats of Jobos Bay, and 2. To describe a monitoring plan for Jobos Bay designed to assess the impacts of conservation practices implemented on the watershed. This characterization is a component of the partnership between the U.S. Department of Agriculture (USDA) and the National Oceanic and Atmospheric Administration (NOAA) established by the Conservation Effects Assessment Project (CEAP) in Jobos Bay. CEAP is a multi-agency effort to quantify the environmental benefits of conservation practices used by private landowners participating in USDA programs. The Jobos Bay watershed, located in southeastern Puerto Rico, was selected as the first tropical CEAP Special Emphasis Watershed (SEW). Both USDA and NOAA use their respective expertise in terrestrial and marine environments to model and monitor Jobos Bay resources. This report documents NOAA activities conducted in the first year of the three-year CEAP effort in Jobos Bay. Chapter 1 provides a brief overview of the project and background information on Jobos Bay and its watershed. Chapter 2 implements NOAA’s Summit to Sea approach to summarize the existing resource conditions on the watershed and in the estuary. Summit to Sea uses a GIS-based procedure that links patterns of land use in coastal watersheds to sediment and pollutant loading predictions at the interface between terrestrial and marine environments. The outcome of Summit to Sea analysis is an inventory of coastal land use and predicted pollution threats, consisting of spatial data and descriptive statistics, which allows for better management of coral reef ecosystems. Chapters 3 and 4 describe the monitoring plan to assess the ecological response to conservation practices established by USDA on the watershed. Jobos Bay is the second largest estuary in Puerto Rico, but has more than three times the shoreline of any other estuarine area on the island. It is a natural harbor protected from offshore wind and waves by a series of mangrove islands and the Punta Pozuelo peninsula. The Jobos Bay marine ecosystem includes 48 km² of mangrove, seagrass, coral reef and other habitat types that span both intertidal and subtidal areas. Mapping of Jobos Bay revealed 10 different benthic habitats of varying prevalence, and a large area of unknown bottom type covering 38% of the entire bay. Of the known benthic habitats, submerged aquatic vegetation, primarily seagrass, is the most common bottom type, covering slightly less than 30% of the bay. Mangroves are the dominant shoreline feature, while coral reefs comprise only 4% of the total benthic habitat. However, coral reefs are some of the most productive habitats found in Jobos Bay, and provide important habitat and nursery grounds for fish and invertebrates of commercial and recreational value.

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北京市郊区可持续景观生态规划及优化生态生产范式研究是指要遵循区域自然地理要素的分异规律,以土地利用现状格局为基础,以景观生态学原理和可持续发展准则为理论指导,以景观空间分析为具体研究内容来揭示区域土地利用类型结构、功能的异质性和有序性,以期提出优化的土地利用格局。本论文主要通过大量数据、图件的收集、野外考察与调查,文献查阅与数据处理、分析,得出以下主要结论: 一、理论方面 基于景观生态学理论——景观要素,空间结构与生态学过程,景观动态,异质性,等级结构,连接度以及景观的时空性等,以北京地区为例阐述了景观生态学理论如何合理地整合于生态建设与保育之中,并重点阐释了北京生态建设与保育“小三圈”格局的结构与功能,该系统包括山区外圈层、郊区平原中圈层和城区内圈层,其目标要实现:(1)山区发挥以水源涵养、水土保持防护为主的生态功能;(2)郊区创建农田、林地、草地异质性的人工稀树草原景观,形成带、网、片、点相结合的绿网系统;(3)城区以自身绿化和美化为主。同时,本研究针对我国的区域可持续发展进一步提出更加有效的建设性意见:(1)开展区域生态适宜性评价;(2)区域水平的土地利用格局、动态以及预测性研究;(3)进行区域可持续景观生态规划,建立区域优化生态生产范式,最终实现可持续发展目标。 二、研究方法方面 利用空间自相关指数,并结合“城-郊-乡”梯度分析法研究景观格局对尺度(包括粒度、幅度、方向)变化的响应。得出以下主要结论: 1、景观格局对于尺度变化有着不同的响应,随着空间粒度的增加,空间自相关均呈下降趋势;随着幅度的增加,空间自相关基本不变;人类干扰较多的景观几乎不受“划区效应”的影响;不同的数据类型,同一数据类型的不同景观对于尺度的变化均有着不同的响应。 2、沿“城-郊-乡”样带,空间自相关呈阶梯状增加趋势。景观空间自相关大小顺序:林牧景观>林果景观>农田景观>都市景观>都市化景观,人为干扰较多的景观具有较低的空间自相关,但对尺度的变化表现出较强的敏感性。 三、实例研究 北京市郊区可持续景观生态规划及优化生态生产范式研究是以昌平区为例,从昌平区经济与产业结构现状分析出发、以昌平区土壤理化性状分析为背景,以景观格局现状、动态,以及土地利用内部转移格局与过程、驱动因素分析为主要内容,并且重点探讨了昌平区城镇化的过程特征及空间特征,得出以下主要结论: 1、昌平区GDP配比方式,以及昌平区农村GDP结构模式均为“三二一”。昌平区在北京市农业中的地位,以及农业在昌平区GDP中所处地位均弱化。截止2001年,昌平区农业产值中,牧业>种植业>渔业>林业,牧业居于首位,占到46.70%,而传统种植业也正以小汤山为龙头向现代化、高科技、高效化的“六种农业”转化。总体讲,农业的粮食生产功能在昌平区已不再是一个重要功能,传统种植业正逐步地让位于畜牧业(人工牧草)、林业(疏林、苗圃),突出体现了具有良好生态学效益的牧草、林果在未来大农业发展中的战略地位。 2、昌平土壤肥力状况良好,景观分区与土壤理化性质是吻合的。基于土壤理化基质,昌平区应形成林、灌、草为主的山区景观,园林式城镇、林、果、灌相结合的山前倾斜平原景观,以及农、林、草配置的生态农业景观和花卉、种苗、绿化带相辉映的绿色生态住宅景观。 3、从1989~2001年期间,研究区内土地利用景观经历了很大的变化。土地利用景观的量变主要体现在城镇用地的迅速扩张和耕地的锐减,而土地利用类型的变化则体现在水田、传统菜地的逐渐消失,以及2001年后人工牧草的大面积推广种植。景观格局在不同景观分区的差异也得以论证,中北部山麓平原卫星城镇、旅游林果区(III)具有最高的多样性和最低的优势度、聚集度,中南部平原高科技、都市生态农业区(II)的多样性最低,而优势度、聚集度最高,对于南部平原都市边缘、城镇住宅区(I)各指标则介于III和II区之间。 4、从1989~2001年期间,土地利用的内部转移主要体现在耕地向城镇用地的大面积转移,其次,传统菜地转向城镇用地和其他种植耕地,而人工牧草是由部分耕地转移而来的。城镇化、水资源短缺和农业政策是主要驱动因素。土地利用的内部转移具有明显的区域差异,中北部山麓平原卫星城、旅游林果区体现出卫星城镇的发展,南部平原都市边缘住宅区则反映出北京都市边缘的向外扩张,而中南部平原高科技都市农业区则正向现代化的、高科技都市农业示范区发展。 5、昌平区三种主要的城镇化模式,即都市边缘带状城镇扩展模式、交通主轴线状城镇扩展模式和卫星城面状城镇扩展模式。研究表明,昌平区的城镇化主要集中在1989~1996年期间。 基于昌平区的产业与经济结构现状,土壤养分状况,景观结构现状、动态,土地利用转移方向,并且结合昌平区自然地理分异规律,社会经济因素对昌平区进行了可持续景观规划,昌平区应遵循的四个景观分区为:北部中低山生态保护、生态旅游区;中北部山麓平原卫星城镇、旅游林果区;中南部平原高科技、都市生态农业区;南部平原都市边缘、城镇住宅区。 最后作为总结、归纳,我们提出昌平区优化生态生产范式,昌平区的发展应定位于(1)生态环境保护与水源涵养的生态功能;(2)教育、示范、创新功能;(3)生活功能,并且遵循自然地域分异规律原则、因地制宜原则、生态主导性原则、统筹兼顾原则,大力发展昌平区经济的优势产业,即畜牧业、林果业和旅游业,突出肉羊、苹果、牧草和林木种苗等四个具有昌平特色的主导产业。 景观生态学;景观空间格局;可持续景观生态规划;土地利用变化;优化生态生产范式;北京昌平区