红树林保护的意义和建议

红树林是热带和亚热带海岸带上特有的森林群落,在净化海水、抵挡风浪、保护海岸、改善生态状况、维护生物多样性和沿海地区生态安全等方面发挥着重要作用。然而,由于围海造田、围垦养殖以及城镇发展等原因,我国红树林面积正在日益减少,红树林湿地保护问题已成为世界关注的热点问题之一。笔者结合工作体会,简述保护红树林的意义及对如何保护好现存的红树林提出建议。     

广东沿海红树林生态修复模式研究

通过深入调查研究广东沿海红树林生态系统资源及保护现状，针对近年因围垦养殖、城市建 设发展用地、城市生活污水和工业污水大量排放等，导致一些红树林及其生态环境遭到破坏，面积大幅减 少；现有红树林群落植物种类偏少、结构简单、遗传多样性水平较低；互花米草等外来有害生物入侵严 重，林分质量下降、系统功能退化；加上沿海红树林恢复属困难立地造林，技术措施及建设成本要求高等 实际情况，结合广东沿海滩涂立地条件及红树林经营管护特点等，提出了相应的红树林生态保护修复模式 及特殊立地修复营建关键技术等，为沿海红树林生态系统保护、修复、营建等提供理论依据和技术指导。     

Mangroves of China: a brief review

The distribution, ecology, conservation and management of Chinese mangroves are reviewed. Mangroves naturally occur along the southeast Chinese coast and traverse the provinces of Hainan, Guangdong, Guangxi, Fujian and Taiwan, intermittently extending from 18°N. Thirty-seven mangrove tree species, representing 20 families and 25 genera, have been documented, with thermophilic eurytopic species being the dominant components. A remarkable decrease of species richness is evident from Hainan (18–20°N) to Fujian (23.5–27°N) (35 vs. 9 species). The existing mangrove area is ≈ 17 800 ha, accounting for slightly more than 0.1% of the world's total. Nearly two-thirds of China's mangroves have been lost during the past 40 years, largely due to conversion for rice-farming, embankment for aquaculture ponds and, recently, rapid urban development. A total of 201 papers on Chinese mangroves was published between 1950 and 1995, 178 of which are in Chinese; thus, they are not easily accessible to the international scientific community. Most of the work was conducted after 1985 (91% of the papers published) and research emphasized floristics with little attention to managementrelated issues. The net primary production of the Chinese mangroves shows a latitudinal trend, also significant deviations from predictions on models generated using non-Chinese data. Although 28 Chinese institutions have dealt with mangrove research, only five maintain long-term projects. The bulk of research has been carried out in six mangrove reserves: Qinglan, Dongzhai (Hainan), Mai Po (Hong Kong), Futian (Guangdong), Shankou (Guangxi) and Jiulongjiang (Fujian). Twelve mangrove reserves have been established so far in mainland China, one in Hong Kong (Mai Po) and one in Taiwan (Tanshui). These reserves cover an area of over 19000 ha, of which 8445 ha are mangroves (47% of existing mangrove area). Six measures that can facilitate mangrove conservation and management are recommended: (a) declare more mangrove areas as nature reserves; (b) set up a national mangrove committee and mangrove research centre to foster research and management; (c) develop concrete management guidelines; (d) enact protective legislation and ensure its strict enforcement; (e) launch education programmes in the major mangrove reserves; and (f) stop further nonsustainable exploitation of mangroves and their habitats.     

中国广东红树林资源现状与保护对策

According to the survey of Guangdong mangrove resource in 2001 and author‘s field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim,aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.     

广东省红树林分布现状与动态变化研究

广东省是全国红树林分布面积最大的省份。开展红树林分布与动态变化研究,有利于促进红树林的保护、恢复和合理利用。采用遥感区划与现地调查相结合的研究方法,对广东省红树林现状分布进行了调查。研究结果表明,广东省现有红树林面积为12 039.80 hm2,主要集中分布在雷州半岛、粤西区域和珠江口区域;斑块比较破碎;红树林起源以天然林为主,但人工林的面积比例逐年增加;红树林保护情况较好,85.5% 的红树林纳入了各级保护区。与2001 年相比,广东红树林面积有所增加,但天然林面积有所减少,树种、起源结构也发生了相应的变化。对红树林的保护和培育方向提出了建议。     

红树植物亲缘地理学研究进展

红树植物生长在热带、亚热带海岸滩涂上。健全的红树植物生态系统是人类持续利用红树林的必要条件。如何保护、维持红树林的生态系统及其遗传健全性已成为红树林生态学家最关心的问题。红树植物当前的地理分布格局及形成原因是生态学家和保护生态学家的研究重点。文中介绍了近些年来红树植物亲缘地理学研究概况,包括地理隔离对红树植物分布格局的影响、基因交流受阻隔以及引起红树群体遗传结构变化的原因等内容;阐述了地质历史引起地形地貌变化、地理隔离、繁殖体扩散及生境环境等因子影响红树群体遗传演化的机制;探讨了红树植物亲缘地理学未来研究的重点,以期为红树植物保护和相关研究提供参考。     

红树林对潮汐浸淹适应性研究进展

海平面上升引起潮汐水位降低和淹水时间增加,探明红树林对潮汐淹浸适应的生理生态特性有助于科学保护和修复红树林,而且科学选取红树林营林宜林地也需要了解红树林与潮汐浸淹之间的相互关联。文中从红树林潮汐浸淹的研究方法出发,重点论述水淹胁迫对红树植物形态表征、光合作用、呼吸作用、抗氧化系统、渗透调节物质和化学计量特征的影响,以及潮汐浸淹下红树植物分子生物学机制,以期为揭示红树植物对潮汐浸淹的适应机制以及全球气候变化背景下我国红树林造林实践和宜林地选择提供参考。     

吕梁市域生物多样性保护的生态安全格局

城市生物多样性保护是食物生产、人类健康和城市安全的必要保障,生态安全格局的构建能够维护自然生态平衡、保持生境稳定性和提高景观连通度,是生物多样性保护的重要空间途径。以吕梁市为例,采用形态学空间格局分析法和景观连通性指数法定量评估生态斑块重要性,辨别生态源地,利用最小累积阻力模型提取生态廊道和战略点,构建市域生物多样性保护的生态安全格局。结果表明:景观格局中核心区、桥接区、孤岛为林地和水域要素主要构成;沿吕梁山脉带状分布的生态源地景观连通性较大,西部生态源地面积较小且斑块重要性相对较低;"两纵,多横"的生态廊道布局和战略点布设,有效提高了市域生态结构的完整性。研究结果可以为市域尺度生物多样性保护规划提供思路和方法。     

基于最小累计阻力模型的卢氏县土地生态适宜性评价

按用途可将城市土地景观划分为生态用地和建设用地两部分,这两部分用地扩张可以看作是此消彼长的动态过程。采用ArcGIS软件模拟土地扩张运动,构建以两个过程最小累计阻力差值模型为基础的城市土地适宜性评价机制。以河南省三门峡市卢氏县为例,选取建设用地和生态用地作为土地扩张源,分别从土地固有生态属性因子、外延生态属性因子两个因子,8个方面建立阻力评价体系。评价结果表明,适宜生态保护用地扩张面积为932.14 km²,占县域面积的23.28%;适宜建设用地扩张面积为3 071.87 km²,占县域面积的76.72%。运用最小累计阻力差值模型将卢氏县划分为生态开发不困难、一般困难、较困难、困难4个区域,各区域面积分别为176.18、755.96、811.61、2 260.26 km²,分别占县域面积的4.40%、18.88%、20.27%、56.45%。适于建设用地开发的难易程度分区与适宜生态保护用地相反。     

Autologistic regression and multicriteria evaluation models for the prediction of forest expansion

Land use changes are complex ecological processes driven by the interaction of biophysical and human related factors. The prediction of forest land use changes is important for sustainable forest management and biodiversity conservation. This study investigates the modelling process of the spatial dynamics of a forest ecosystem in north eastern Greece. For the prediction of forest expansion, based on land use data of the study area, a deterministic approach using logistic regression and heuristic methods of multi-criteria evaluation is adopted. The set of factors driving forest expansion are: the slope, the distance to roads, the distance to urban areas, the distance to forest, the soil depth, the soil erosion and the influence from the land uses of the neighbourhood. The spatial autocorrelation of driving factors is addressed using an autologistic regression model. The multicriteria evaluation approach is developed using weighted linear combination (WLC) and ordered weighted averaging (OWA) methods. In WLC method the relative importance of each factor was estimated using the analytical hierarchy process. In the OWA method, decision strategies are generated using a selection of relative linguistic quantifiers, which allow different Risk in decisions. The accuracy of the models produced was tested with real data for the year 2001 using the ROC validation method. All the methods produced satisfactory results. Autologistic regression showed slightly better performance than multicriteria evaluation methods due to higher degree of objectivity in defining the importance of driving factors for forest expansion.     

基于1990-2020年综合土地利用动态变化的巩义市城市边缘区空间研究

以郑州市下辖且接壤的巩义市为研究对象,以1990年和2020年两期TM/OLI影像和统计年鉴数据为依据,使用1 km×1 km网格划分样区并提取各样区的综合土地利用动态度数值,借助数学模型分析确定城市边缘区范围,分析巩义市近30年来城市边缘区用地变化特征及扩展机制。结果表明,自然条件是用地扩张的基础因素,政策与经济是边缘区外扩的核心驱动力,交通对扩张具有指向性作用;边缘区内的土地变化主要表现为建设用地急剧增加、农业用地锐减,同时受距离和开发时序影响,用地类型交错复杂,破碎化特征明显。     

Protection vs. commercial management: Spatial and temporal analysis of land cover changes in the tropical forests of Central India

Tropical forests worldwide are undergoing rapid changes due to increasing human populations and varied land use practices. In an effort to protect these forests and their species, the number of protected areas has increased exponentially in recent decades. Clearly protected areas play a crucial role in conservation efforts and this strategy has been found to be successful in several studies. However, protected areas are often embedded within a matrix of other land cover types, including non-protected forests, agricultural fields, or urban areas. It is therefore critical for park management to think beyond the borders of their protected areas and work to maintain ecological integrity of the surrounding matrix and the connectivity between protected areas. This study integrates remote sensing, GIS and field observations to examine the effects of different management strategies on land cover changes. As a case study we examine a tiger reserve in Central India which is surrounded by commercially managed forests, representative of many protected areas throughout India. Findings of this study show that while protected areas play an important role in conservation, alternative approaches including favorable management policies could also be effective to extend conservation over larger areas.     

珠江口红树林湿地保护与修复的基本思路

珠江口是珠江出海口流经区域的简称,包括香港、澳门特别行政区和广州市、深圳市、珠海市、东莞市、中山市等。历史上该地区曾分布着大片的天然红树林,但是由于社会经济的快速发展,红树林资源遭到不同程度的破坏。文章将珠江口沿岸红树林湿地作为一个整体区域进行考虑,提出实施保护工程的基本思路,通过红树林保护工程、红树林恢复工程等措施,全面恢复湿地功能,改善区域河口生态环境,保护生物多样性,增强红树林防御台风、海啸、赤潮等自然灾害的能力。     

Mangrove expansion and population structure at a planted site,East London,South Africa

Avicennia marina (Forrsk.) Vierh. was planted in 1969 at Nahoon Estuary, East London, followed a few years later by the planting of Bruguiera gymnorrhiza (L.) Lam. and Rhizophora mucronata (L.) among the larger A. marina trees. This study tested the hypothesis that mangroves have expanded and replaced salt marsh over a 33-year period (1978–2011). It provides important information on mangroves growing at higher latitudes, where they were thought to not occur naturally due to lower annual average temperatures. It further provides insights on future scenarios of possible shifts in vegetation types due to climate change at one of the most southerly distribution sites worldwide. The expansion of mangroves was measured using past aerial photographs and Esri ArcGIS Desktop 10 software. In addition, field surveys were completed in 2011 to determine the population structure of the present mangrove forest and relate this to environmental conditions. The study showed that mangrove area cover increased linearly at a rate of 0.06 ha y^?1, while the salt marsh area cover also increased (0.09 ha y^?1) but was found to be variable over time. The mangrove area is still relatively small (<2 ha) and expanded mostly over a bare sandflat area. Avicennia marina was the dominant species and had high recruitment (seedling density was 33 822 ± 16 364 ha^?1). Only a few Bruguiera gymnorrhiza and Rhizophora mucronata individuals were found (<10 adult trees), although observations indicate that some young plants are becoming established away from the parent plants. The site provides opportunities for studies on mangrove/salt marsh interactions in response to a changing climate. Mangroves should not be planted in non-native areas as they may become invasive outside their natural range. However, future increases in temperature will certainly lead to a southerly expansion of mangoves in South African estuaries.     

惠东县红树林资源现状及保护对策

通过卫星遥感和设置样地对广东省惠东县的红树林资源进行调查。结果表明:惠东县红树林面积共有1361.83 hm^2,其中,红树林有林地有400.15 hm^2,红树林未成林造林地有42.27 hm^2,红树林宜林地有919.41 hm^2;共分布15种红树植物,其中真红树植物有9种,半红树植物有6种,另外红树林伴生植物有29种。对惠东县红树林基本结构情况和多样性、原生性、濒危性资源特点进行了分析,指出红树林正受到人工围垦养殖、旅游开发建设、外来生物入侵、污水直排和生活垃圾污染水体、外来无瓣海桑Sonneratia apetala红树林物种影响等威胁因素,提出了出台相关保护政策、严格执法、营造多树种混交红树林群落、对近海滩涂养殖进行规范、规模控制、对滨海乡镇实施垃圾清理工程和污水集中处理设施建设、合理划定保护区范围及功能区等保护和发展对策,为红树林的生态保护与恢复以及海岸修复提供参考。     

深圳福田红树林资源保护与生态旅游开发

福田红树林自然保护区是深圳市得天独厚的一块生态资源宝地。为了维护红树林湿地的生态平衡,保护宝贵的生态资源,本文从多个方面提出了进行生态恢复的措施,并进一步提出发展生态旅游业是实现红树林资源保护和利用相协调的最佳途径。     

滇中地区生态环境脆弱性对景观动态变化的响应 ——以云南清华洞国家森林公园为例

基于GIS技术,对云南清华洞国家森林公园2010—2019年的土地利用进行分类和统计,选取分维数、景观形状指数、香农多样性指数、香农均匀度指数、破碎度、分离度、脆弱度指数、生态环境脆弱度等8个景观评价指标,探讨在景观格局变化背景下生态环境脆弱性的变化特征。结果表明:森林公园的景观格局以林地为基底,建设用地、农地、水域零星分布;景观格局指数的变化驱动力主要为人类活动;森林公园的景观类型整体多样性水平较低,总体上有随时间变化而均匀化增大的趋势;各景观类型中,建设用地、裸地、农地的生态环境脆弱性较高,天然乔木的生态环境脆弱性最低;生态环境脆弱性变化趋势与资源的保护力度呈负相关关系,水目山片区的生态环境脆弱性虽然高于清水河片区,但随时间的变化脆弱性有逐渐降低的趋势。从整体上看,高级区主要分布于人类活动频繁区域。     

中国红树林资源与保护

系统回顾了中国红树林40a来主要研究成果，分析了我国红树林树种、资源分布；各省（区）红树林资源概况；全国红树林资源保护现状及存在的问题；提出了保护与利用红树林资源的若干建议。     

珠江口红树林湿地保护规划的基本思路

珠江口是珠江出海口流经区域的简称,包括香港、澳门特别行政区和广州市、深圳市、珠海市、东莞市、中山市等。历史上该地区曾分布着大片的天然红树林,但是由于社会经济的快速发展,红树林资源遭到不同程度的破坏。文章将珠江口沿岸红树林湿地作为一个整体区域进行考虑,提出实施保护工程的基本思路,通过红树林保护工程、红树林恢复工程等措施,全面恢复湿地功能,改善区域河口生态环境,保护生物多样性,增强红树林防御台风、海啸、赤潮等自然灾害的能力。     

Mangrove management for climate change adaptation and sustainable development in coastal zones

Due to their prevalence in developing countries and the range of ecosystem services they provide, projects aimed at promoting mangroves align with several of the UN Sustainable Development Goals—specifically Goals 13, 14, and 15—which concern adaptation to climate change and the sustainable management of forest and coastal resources. Although mangroves themselves are sensitive to climate change, they also provide services that would help reduce damages, by sequestering carbon, enhancing coastline stability, and protecting coastal settlements from tropical storm surges. In particular, mangroves can rapidly colonize and stabilize intertidal sediments, promoting coastal accretion to reduce the impact of sea level rise. The Government of Bangladesh has established mangrove plantations with the intent to accelerate accretion and stabilize 120,000ha of coastland. As a case study, this paper uses GIS data on coastal dynamics and land cover to evaluate the effectiveness of mangrove plantations for facilitating accretion and preventing erosion in Bangladesh. The results indicate that plantation areas experience greater rates of accretion relative to erosion than non-plantation areas, confirming that mangroves have an important role to play in the sustainable development of coastal regions.