PEATLAND CONVERSION AND DEGRADATION PROCESSES IN INSULAR SOUTHEAST ASIA: A CASE STUDY IN JAMBI,INDONESIA

The ongoing conversion and degradation of insular Southeast Asian peat swamp forests causes globally important carbon emissions and leads to loss of unique biodiversity. Little quantitative information is available on the dynamics of peat swamp forest conversion. In this case study, we present a time‐series of peatland conversion and degradation in the Air Hitam Laut peatlands in Jambi Province (Sumatra, Indonesia), which included the Berbak National Park. High‐resolution (10–60 m) satellite imagery was used to map land cover and degradation status for nine time slices between the 1970s and 2009. Nearly‐pristine forest cover was shown to have declined in the study area from 90 to 43 per cent, inside the Berbak National Park from 95 to 73 per cent and outside the National Park from 86 to 25 per cent. Outside the protected area, 66 per cent of former nearly‐pristine forests turned into degraded forests or unmanaged deforested areas. Large‐scale oil palm plantations accounted for 21 per cent of the formerly nearly‐pristine areas and small‐holder agriculture for 8 per cent. The conversion to plantation has fast accelerated since 2002. Conversion from nearly‐pristine forest to plantation typically took around 6 years, at times up to 10 years. Better understanding of conversion and degradation dynamics will allow for improved estimates of the implications of management planning decisions taken in peatland areas. Copyright © 2011 John Wiley & Sons, Ltd.     

Beyond the forest edge: Ecology, diversity and conservation of the grassy biomes

Forests and grassy vegetation (savannas and grasslands) are alternative ecosystem states in many tropical landscapes. Relative to forests the grassy ecosystems are poorly known and poorly conserved, partly because they were thought to be products of forest clearance. However many grasslands have proved to be ancient. Commensurate with their antiquity, grassy biomes have distinct suites of plant and animal species that contribute a large fraction of the diversity of forest-grassland mosaics. Grasslands differ strikingly from forests in their ecology and in the nature of threats to their future. Here we highlight the high biodiversity value of grassy biomes and, in contrast to tropical forests, we illustrate the importance of fire in maintaining these systems. We discuss the major threats to, and consequences for, biodiversity in these regions including land clearance and elevated CO₂-driven forest expansion. Finally we focus on the difficulties of grassland restoration. A new approach to understanding and conserving grassy ecosystems, free from cultural prejudices of the past, is long overdue.     

Transition from Forest‐based to Cereal‐based Agricultural Systems: A Review of the Drivers of Land use Change and Degradation in Southwest Ethiopia

The southwestern Ethiopian montane forests are one of the most species‐rich ecosystems and are recognised globally as a priority area for the conservation of biodiversity. Particularly, in contrast to the drier central and northern Ethiopian highlands, they have received little attention by researchers. Here, we review changes to agricultural systems in and around these forests that are known as the genetic home of coffee (Coffea arabica L.) and that are important to the livelihoods of many rural people who have developed traditional management practices based on agro‐ecological knowledge, religious taboos and customary tenure rights. We explored the impacts of conversions to agroforestry and cereal‐based cropping systems on biodiversity, soil fertility, soil loss and the socio‐economic conditions and culture. The increasing trend of cereal cropping, resettlement and commercial agriculture causes the deterioration of natural forest cover in the region and threatens biodiversity, land quality, sustainable, traditional farming practices and the livelihood of the local community. Large‐scale plantations of tea, coffee, soapberry locally known as endod (Phytolacca dodecandra L'Hér.) and cereals have resulted in biodiversity loss. Following the conversion of forests, cultivated fields exhibit a significant decline in soil fertility and an increase in soil loss as compared with the traditional agroforestry system. The establishment of a sustainable agricultural system will require a change in paradigm, whereby the intrinsic values of the traditional forest‐based agricultural system are recognised, rather than the ongoing mimicking of agricultural policies that were developed for the open fields of central Ethiopia. Copyright © 2016 John Wiley & Sons, Ltd.     

自然解决方案背景下的辽宁省森林生态系统服务主导功能评估

[目的] 对辽宁省森林生态系统的主导服务功能进行评估，并分析其作为基于自然的解决方案的意义和可行性，为探索符合中国国情的基于自然的解决方案（NbS）提供理论依据。[方法] 基于辽宁省2017年森林资源2类调查数据，根据中华人民共和国国家标准《森林生态系统服务功能评估规范》（GB/T38582-2020），应用分布式测算方法，对辽宁省森林生态系统绿色水库、绿色碳库、净化环境氧吧库和生物多样性基因库4项主导服务功能进行评估，并探讨其对于解决社会挑战的贡献。[结果] 全省4大主导功能价值量分别为：1.71×10¹¹，8.24×10¹⁰，3.40×10¹⁰，9.69×10¹⁰元/a。森林生态系统服务功能整体上呈现：辽东山区>辽西北地区>辽中南平原沿海地区的分布格局，丹东市、抚顺市和本溪市各项服务功能较高，沈阳市、锦州市和盘锦市各项服务功能较低。[结论] 在全球变化和实现可持续发展目标时间越来越紧迫的背景下，基于自然的解决方案的内涵与生态系统服务对人类福祉的贡献不谋而合。森林生态系统各项服务功能的充分发挥有助于解决气候变化、生物多样性丧失、环境退化等问题。     

北方土石山区生态修复与水源涵养研究进展与展望

生态文明建设与生态环境保护是人与自然和谐相处与和谐共生的必然要求,是实现经济社会可持续发展和人民群众对美好生态环境的现实需要、建设美丽中国的实际需要。针对太行山区生态系统严重退化、环境容量与承载力低下、基础设施薄弱、自然条件与资源禀赋较差、贫困程度较深等问题,中国科学院遗传与发育生物学研究所农业资源研究中心从20世纪80年代开始在太行山中段东坡的低山丘陵区进行生态修复与可持续发展的研究,通过30年的研究实践,提出并建立了较为完整的北方土石山区生态修复治理体系,为山区生态文明建设和生态环境保护,以及扶贫攻坚和社会经济可持续发展提供了经验与示范。本文通过30年研究历程回顾、研究与展望,总结了土石山区生态修复与水源涵养的进展与展望。太行山林业生态工程建设主要经历了3个阶段:一是研究初始阶段(1986—1996年),确定了退化山地生态系统恢复的途径与技术理论,建立了以水土富集为中心的林业生态工程。二是提升发展阶段(1997—2007年),这一阶段主要是研究了影响退化山地生态系统恢复与重建的关键因子与影响机制,并提出了有效的技术措施与解决方案。具体说来,在径流林业研究方面,研制出了太行山水土富集工程带间距计算公式;在降水资源转化与水分运移规律研究方面,明晰了岩土二元结构体的降水-土壤水-裂隙水的基本补给路径,揭示了岩土界面"优先流"与裂隙网络"优先流"的运行转化规律,阐明了浅层风化裂隙岩体渗流的动态变化特征及对植被耗水过程的响应关系;在降水资源调控利用研究方面,研制出了生物集雨新材料、营养调理剂和生物集雨面建造施工工艺。三是全面创新阶段(2008年—),重点探讨了山区生态产业开发与区域可持续发展问题,研发了经济林土壤扩蓄增容技术、石质山地困难立地造林技术、经济林生态隔离带调控技术、京津风沙源治理工程区沙产业开发技术,以及林下经济、循环经济、生态旅游等生态产业化技术体系。下一步将在目前研究的基础上,向人口密度较大、人类活动频繁的雄安新区上游山区扩展,重点开展以国土绿化、景观建设、水源涵养、水土流失治理、污染防治为主要内容的山水林田湖草一体化生态环境与气候变化监测,研究现代干扰条件下山地灌丛生态系统向森林生态系统的演替过程及主要驱动因素,山地水旱灾害形成机制、降水资源调控与水源涵养,以及以产业生态化和生态产业化为主体的山地生态经济体系,为构建结构稳定、功能完善的京津冀生态环境支撑体系与水源涵养功能体系提供科学依据和技术支撑,为山地生态系统经营管理,实现其生产、生态功能和系统稳定性提供科学参考。     

Biodiversity conservation in human-modified landscapes of Mesoamerica: Past, present and future

Mesoamerica provides a unique context for biodiversity conservation in managed landscapes because of its geography, history of human intervention, and present conservation and development initiatives. The long and narrow form of the Mesoamerican landmass, and its division by a central mountain range, has served as both a bridge and a barrier. Conservation efforts in Mesoamerica are unique for the emphasis they place on regional connectivity through the Mesoamerican Biological Corridor and on biodiversity conservation in managed landscapes. The emphasis on conservation in agricultural systems has fostered innovations in payment for ecosystem services, and provides novel insights on the functional role that biodiversity plays in the provisioning of ecosystem services. The increasing rate of economic development in the region and the advent of new payment for ecosystem service schemes have provided new opportunities for forest regeneration and restoration. However, the small scale of private landholdings and the diversity of land uses featured in the region, while contributing to biodiversity conservation due to their structural and floristic complexity, present challenges for biodiversity monitoring and management.     

丛枝菌根生理生态功能及其在生态恢复中的作用

近年来生态系统退化、环境污染等问题日趋严峻,生态恢复成为国内外关注的热点之一。丛枝菌根是陆地生态系统中分布最广泛、最重要的互惠共生体之一,对提高植物抗逆性、植被恢复、保持生态系统稳定与可持续生产力的作用显著。本文重点综述丛枝菌根的生理生态功能,及其在矿区土壤、旱区和盐碱土壤、退化草原等生态重建中的应用潜力,并对未来研究方向进行了探讨,旨在为生态恢复提供一条新途径。     

Conserving forest biodiversity across multiple land ownerships: Lessons from the Northwest Forest Plan and the Southeast Queensland regional forests agreement (Australia)

As the area of the world’s forests shrinks, the management of production forests is becoming increasingly paramount for biodiversity conservation. In the United States and Australia, public debate and controversy about the management of production forests during the later decades of the 20th century resulted in governments adopting sweeping top-down changes to forest policy, with regional forest plans a cornerstone of this process. This paper reviews the biodiversity conservation outcomes of two such processes, the Southeast Queensland Forests Agreement (Australia) and the Northwest Forest Plan (United States). Several key lessons are identified. First, these plans are significant steps forward in the struggle to conserve forest biodiversity while providing for production of timber. Second, expanding the conservation reserve system by itself does not necessarily ensure biodiversity conservation, especially if reserves are traded off for increased timber harvesting in forests outside of reserves or if certain important elements of biodiversity are not accounted for either by conservation forests or production forests. Third, reserves often need active management to restore diversity in previously-logged forests and reduce fuels that have accumulated as a result of fire exclusion. Fourth, the current plans fall short of the comprehensive whole-of-landscape, multiple-ownership approach needed to support long-term sustainable forestry and biodiversity conservation. Fifth, adaptive management was not adequately institutionalized and sometimes misapplied, although, in the case of the Pacific Northwest, a major regional monitoring strategy was developed and partially implemented. Finally, ecological science suffered in the collision with the socio-political decision-making process due to the limited scope that was left for testing and evaluating the new approaches to forest management. We conclude, based on the evaluation of the two regional plans, that regional biodiversity conservation goals may be better achieved by implementing sustainable forest management practices across all ownerships and involving all stakeholders and the broader community.     

Regrowth forests on abandoned agricultural land: A review of their habitat values for recovering forest fauna

Human land use has modified the structure and function of terrestrial landscapes throughout much of the world, with cropping and livestock grazing the major drivers of landscape change. In many tropical, sub-tropical, temperate and Mediterranean regions, regrowth forests regenerate naturally on abandoned agricultural land if human disturbance declines. With the exception of some tropical forest literature, the broader ecological and conservation literature has largely ignored the potential of regrowth forests to facilitate passive landscape restoration and the recovery of fauna communities in fragmented agricultural landscapes. This paper addresses this deficiency by reviewing the available global evidence of fauna recovery in regrowth forest from 68 papers, identifying the main gaps in current knowledge, and providing directions for further research. The majority of reviewed studies focus on regrowth in tropical regions, which often contain large areas of mature forest. Species’ utilisation of regrowth forest is highly variable and is particularly influenced by land-use history, an important determinant of the structural and compositional characteristics of regrowth forests. While site-scale (<1 ha) forest structure and floristic diversity were frequently studied, only 11 studies considered the spatial configuration and context of habitat patches and just two studies explicitly considered landscape structure. Based on this review, six key research questions are posed to direct future research on this important issue. We conclude that a broader perspective of the role of regrowth forest in the landscape is required if we are to realise the potential benefits of regrowth forest for passive landscape restoration and fauna conservation and recovery.     

Mapping Changes in Land Cover Composition and Pattern for Comparing Mediterranean Rangeland Restoration Alternatives

The limited amount of studies addressing the long‐term effectiveness of restoration actions to combat land degradation is a constraint for current landscape restoration planning and implementation. Remote sensing data provide a unique opportunity for gathering information on the spatial and temporal variability of restoration processes and may contribute to fill this knowledge gap. The aim of this study is to compare different management actions undertaken in Mediterranean degraded rangelands (i.e. dense pine plantations, thinned pine plantations, protection and passive management) by analysing landscape composition and pattern change assessed from object‐based classification of aerial photograph of 1954, 1977 and 2006. Results show a clear link between landscape composition and structure and the different restoration actions, allowing comparison between their spatial and temporal dynamics. All restoration actions promoted an increase in woody vegetation cover compared with non‐restored areas. However, only protection and passive management favoured the restoration of dense, complex and well‐connected patches of native Mediterranean maquis. The proposed methodology is discussed with respect to its applicability for future Mediterranean landscape restoration planning in a wider geographic and ecological perspective. Copyright © 2015 John Wiley & Sons, Ltd.     

Learning from Non‐Linear Ecosystem Dynamics Is Vital for Achieving Land Degradation Neutrality

Land Degradation Neutrality is one of the Sustainable Development Goal targets, requiring on‐going degradation to be balanced by restoration and sustainable land management. However, restoration and efforts to prevent degradation have often failed to deliver expected benefits, despite enormous investments. Better acknowledging the close relationships between climate, land management and non‐linear ecosystem dynamics can help restoration activities to meet their intended goals, while supporting climate change adaptation and mitigation. This paper is the first to link ecological theory of non‐linear ecosystem dynamics to Land Degradation Neutrality offering essential insights into appropriate timings, climate‐induced windows of opportunities and risks and the financial viability of investments. These novel insights are pre‐requisites for meaningful operationalisation and monitoring of progress towards Land Degradation Neutrality. © 2017 The Authors. Journal of Land Degradation & Development published by John Wiley & Sons Ltd.     

Land Use and Cover Dynamics Since 1964 in the Afro‐Alpine Vegetation Belt: Lib Amba Mountain in North Ethiopia

Human‐induced land use and land cover (LUC) changes threaten the ecosystem services of the vulnerable tropical afro‐alpine vegetation. Several LUC change studies are available for the Ethiopian highlands, but relatively little is known about LUC change in the afro‐alpine zones. In this study, LUC changes between 1964 and 2012 were mapped for the afro‐alpine zone of Lib Amba Mountain, part of the Abune Yosef Mountains in North Ethiopia. Historical LUC was derived from georeferenced aerial photographs of 1964 and 1982, and the present LUC (2012) from Bing Map satellite imagery. Based on these successive LUC maps a time‐depth map, LUC proportions, LUC transition matrices and LUC change trajectories were calculated. Two main phases of LUC change could be distinguished linked to the neo‐Boserupian perspective. (i) Between 1964 and 1982, there were large‐scale deforestation and general degradation of the vegetation above 3500 m, in a period of low population pressure; (ii) Between 1982 and 2012, an intensification of land use prevailed accompanied with a slight regeneration of the vegetation and the Erica arborea L. forest, under increased population pressure. Depth interviews indicated that local and governmental land management measures are very important for the protection against vegetation depletion and soil degradation. Quick recovery of the forest on Lib Amba provides confidence that degraded afro‐alpine areas would benefit in a short time from complete protection, given the vicinity of remaining patches of afro‐alpine vegetation. Management interventions are thus vital to restore the important ecosystem services of the afro‐alpine vegetation belt. Copyright © 2015 John Wiley & Sons, Ltd.     

多情景退耕还林对林地生物多样性保护价值的潜在影响

退耕还林对生物多样性保护具有显著的正向影响,评估其生物多样性保护生态服务价值意义重大。现有研究多采用当量法计算生物多样性保护的生态服务价值,但该方法未考虑不同林地类型的差异化生物多样性价值,因而难以实现空间精细化评估。该研究从生态连通视角切入,以云南省保山市施甸县为例,根据坡度和相关政策设定1种现状情景（情景I）与3种退耕情景（情景II、情景III与情景IV）,采用形态空间模式识别生态源地、指数法分析生态连通性和斑块重要性,进而计算各情景下的生物多样性保护的生态服务价值。在此框架中,该研究通过空间精细化手段修正各类林地的当量因子系数。结果表明：随着物种扩散距离的增加,生态连通性增加,情景II、III和IV的森林的生物多样性保护的生态服务价值均呈现增加趋势,依次增加了3.02×107、4.7×106和1.57×107元,更有助于增加生物多样性保护生态服务价值的退耕方式是情景II;从修正当量角度看,情景II、III和IV的修正当量系数分别为1.51、1.46和1.47,最有利的退耕情景为退耕程度最小的情景II,而退耕程度最大的情景III却没有取得相应的成效。研究表明,除退耕程度外,栖息地空间结构和分布也是影响生物多样性保护价值的因素,三者共同构成确定退耕还林形式和建立生态补偿机制的关键依据。同时,该研究通过实地调研和回归模型验证了结果的准确性,为探究其他区域提供理论依据。     

HERBIVORE‐DRIVEN LAND DEGRADATION: CONSEQUENCES FOR PLANT DIVERSITY AND SOIL IN ARID SUBTROPICAL THICKET IN SOUTH‐EASTERN AFRICA

Investigations were made of plant and soil responses to severe degradation through heavy grazing and browsing in arid, succulent, subtropical thicket. Severe degradation of thicket is of major concern in terms of threatened biodiversity, unsustainable utilization and collapse of other ecosystem services. We used a natural, field contrast, case‐study approach, sampling within plots under lightly and heavily stocked conditions. Mean plant species diversity and richness did not change significantly at sample plot level although there was a 27 per cent decline in richness with degradation at the scale of the study site. On degraded plots, there was a high species turnover and high beta diversity, which created a replacement zone rather than an impoverished zone. Replacement species were confirmed as mainly, but not exclusively, weedy annual grasses and alien forbs. The few persisting perennials were small trees that survived above the browse line, and hardy shrub species. Perennial persisting and replacement species below the browse line may suggest potential candidates for restoration. Nitrogen was the only measured nutrient that showed a significant decrease with degradation. Phosphorous, potassium and magnesium increased significantly, with the first two mentioned reaching potentially excessive levels. Soil salinization occurred with an order of magnitude increase in sodium. Thus, the increased cation exchange capacity occurred together with development of a nutrient imbalance. The elevation in some nutrients and soluble salts is ascribed to wind‐determined directional grazing that concentrate livestock in the degraded area. The implications of the above altered soil conditions for thicket restoration need to be further explored. Copyright © 2012 John Wiley & Sons, Ltd.     

Rethinking the ‘back to wilderness’ concept for Sundaland’s forests

Traditional biodiversity conservation approaches emphasize the protection of pristine forests. However, it has become increasingly difficult to secure large tracts of undisturbed forests, particularly in the developing tropics. This has led some conservation scientists and organizations to explore the conservation potential of human-modified habitats, such as selectively logged forests. On the other hand, other scientists have highlighted the perils of overselling the conservation value of degraded habitats and advocate for re-focusing of efforts and resources on protecting primary forests. While there are merits to both contentions, we argue that the “back to wilderness” paradigm has limited relevance in the Sundaland region. This is because: (1) primary forest only makes up a small minority of the remaining forest in the region and most of it is already protected by law; (2) vast areas of selectively logged forest are still susceptible to plantation conversion; and (3) selectively logged forest are important habitats for some of the world’s most endangered species. To meet both conservation and development goals, we suggest that tracts of selectively logged forest be assessed for their ecological value and forests of high conservation value be prioritized for better protection through their inclusion into existing protected area networks and/or improved sustainable forestry management.     

Conserving Southeast Asian forest biodiversity in human-modified landscapes

Southeast Asia experiences one of the highest rates of deforestation in the tropics due to agricultural expansion, logging, habitat fragmentation and urbanization, which are expected to result in species declines and extinctions. In particular, growing global demands for food, biofuel and other commodities are driving the rapid expansion of oil palm and paper-and-pulp industries at the expense of lowland dipterocarp forests, further jeopardizing Southeast Asian forest biotas. We synthesize recent findings on the effects of land-use changes on plants, invertebrates, vertebrates and ecosystem functioning/services in Southeast Asia. We find that species richness and abundance/density of forest-dependent taxa generally declined in disturbed compared to mature forests. Species with restricted ranges and those with habitat and foraging specialization were particularly vulnerable. Forest loss also disrupted vital ecosystem services (e.g. crop pollination). Long-term studies are needed to understand biotic sustainability in regenerating and degraded forests, particularly in the context of the synergistic or additive effects of multiple agents of biodiversity loss (e.g. invasive species and climate change). The preservation of large tracts of mature forests should remain the principal conservation strategy in the tropics. In addition, reforestation and reintroductions of native species, as well as improved connectivity among forest patches could enhance the conservation value of forest remnants in human-dominated landscapes.     

Biodiversity and ecosystem function of tropical forest dung beetles under contrasting logging regimes

A key challenge for tropical conservation biologists is to assess how forest management practices affect biodiversity and associated ecosystem functions. Dung beetles (Scarabaeidae: Scarabaeinae) provide an ideal focal guild for such studies. We compared dung beetle assemblages and experimentally assessed rates of dung removal and seed burial in undisturbed forest, low-intensity selectively logged forest under sustainable forest management, and high-intensity logged forest, not under sustainable management in Malaysian Borneo. In total, 7923 individuals from 39 species of dung beetle were collected. There were no significant differences in abundance, biomass or diversity across sites. Species richness was significantly lower in the high-intensity logged sites. Beta diversity was low: of 35 species recorded in undisturbed forest sites, 32 were also captured in low-intensity sites and 29 in high-intensity sites. The environmental and vegetation variables measured had little influence on species composition. An average of 63–99% of dung was removed over 24 h. Mean dung and seed removal were significantly lower in the high-intensity logged sites. Dung removal rates were significantly and positively correlated with dung beetle species richness, but not with dung beetle biomass or abundance. However, the biomass of large-bodied, nocturnal dung beetles was positively correlated with dung removal. In contrast to previous studies, dung beetle biomass and abundance were not correlated with species richness, indicative of density compensation. Overall, dung beetle communities and associated ecosystem functions were robust to low-intensity but not high-intensity selective logging. These differences may be related to changes in the abundance and biomass of particular dung beetle species or guilds rather than community-wide measures of abundance and biomass, highlighting the need to move beyond simplistic biodiversity-ecosystem functioning correlations to understand the functional consequences of habitat modification in high-diversity ecosystems.     

不同人工恢复林对退化红壤团聚体组成及其有机碳的影响

研究土壤团聚体的组成及其有机碳的分布,有助于从微观角度理解土壤结构与功能的相互作用.采用于筛法和湿筛法,研究南方红壤退化地实施人工恢复30年后,马尾松与阔叶复层林(PB)、木荷+马尾松混交林(SP)和阔叶林(BF)3种典型林分在0～60 cm土层的团聚体组成及其有机碳分布特征,分析土壤团聚体有机碳与总有机碳相关关系.结果表明:各恢复林分土壤机械稳定性团聚体质量分数,以＞2 mm粒径所占比例最大(均在60％以上),而在水稳性团聚体中,以＜0.05 mm粒径占优势.不同林分土壤团聚体结构破坏率顺序依次为BF(53.38％～84.27％) ＞SP(52.22％ ～70.86％) ＞PB(22.70％ ～47.83％).机械稳定性和水稳性团聚体有机碳质量分数均以PB最高,随着土层深度的增加,各林分土壤团聚体有机碳质量分数呈下降趋势.水稳性大团聚体(＞0.25 mm粒径)有机碳质量分数总体高于相应土层的总有机碳质量分数,而微团聚体的(＜0.25 mm粒径)则低于后者,说明有机碳对于大团聚体的形成和水稳性具有积极作用.土壤团聚体有机碳与总有机碳的相关关系分析表明,土壤团聚体有机碳的增加,对总有机碳的积累具有正面影响.保留密度大、灌木(草)层盖度高的马尾松与阔叶复层林土壤团聚体的数量和质量更高;因此,在红壤侵蚀退化地森林恢复初期,可通过适当密植、增加林下灌草覆盖等措施,增加有机碳的输入,促进团聚体的形成和稳定,从而加速了退化土地的土壤结构改善和功能恢复.该研究可为南方严重红壤退化地生态恢复中的林分类型选择和优化配置提供科学依据.     

Assessing the extent and causes of forest degradation in India: Where do we stand?

In India, conservation of biodiversity goes hand in hand with human welfare, as millions of people live adjacent or within protected areas and depend upon forests products. The high density and biomass requirements of these households could result in the degradation of forests and loss of biodiversity. We assessed the collection of forest products among households in five sites in the Western and Eastern Ghats of peninsular India: the Kogar region of the Central Western Ghats, the Bandipur and Sigur regions of the Nilgiri Biosphere Reserve, the Kalakad-Mundanthurai Tiger Reserve of the southern Western Ghats and Similipal Tiger Reserve of the northern Eastern Ghats, and tested whether extraction pressure on forests was associated with the proportion of agricultural households, wage labour and population density. We also examined whether data on loss of cover as stated by the State of the Forest Reports was supported by field data. The regions differed in land use: Kogar, KMTR and Similipal were primarily agricultural regions, whereas households engaged in wage labour or in running small businesses were predominant in Sigur and Bandipur. Fuel-wood was collected ubiquitously for household use in all sites, used mainly for domestic requirements and secondarily for generating income. Green leaves for making fertilizer and fodder were collected for household use and did not enter the market. Cattle manure for the global organic coffee industry was a major forest product in Bandipur and Sigur. Extraction pressure on forests was positively associated with the availability of wage labour and was negatively with the proportion of agricultural households. Data from official sources seem inadequate to measure forest degradation in protected forests. Accurate estimation of forest condition through field assessments and remote sensing, and understanding the socio-economic variables associated with forest loss and degradation are needed for the sustainable management of Indian protected areas.