Causal effects of shelter forests and water factors on desertification control during 2000–2010 at the Horqin Sandy Land region,China

The Horqin Sandy Land(HSL), the largest sandy land in the semi-arid agro-pastoral ecotone of Northeast China, has been subject to desertification during the past century. In response, and to control the desertification,government implemented the Three-North Shelter/Protective Forest Program, world’s largest ecological reforestation/afforestation restoration program. The program began in1978 and will continue for 75 years until 2050. Understanding the dynamics of desertification and its driving forces is a precondition for controlling desertification.However, there is little evidence to directly link causal effects with desertification process(i.e., on the changing area of sandy land) because desertification is a complex process,that can be affected by vegetation(including vegetation cover and extent of shelter forests) and water factors such as precipitation, surface soil moisture, and evapotranspiration.The objectives of this study were to identify how influencing factors, especially shelter forests, affected desertification in HSL over a recent decade. We used Landsat TM imagery analysis and path analysis to identify the effects of spatiotemporal changes in water and vegetation parameters during2000–2010. Desertification was controlled during the study period, as indicated by a decrease in desert area at a rate of163.3 km2year-1and an increase in the area with reduced intensity or extent of desertification. Total vegetation cover in HSL increased by 10.6 % during the study period and this factor exerted the greatest direct and indirect effects on slowing desertification. The contribution of total vegetation cover to controlling desertification increased with the intensity of desertification. On slightly and extremely severe desertified areas, vegetation cover contributed 5 and 42 % of the desertification reduction, respectively. There were significant correlations between total vegetation cover and water conditions(i.e., evapotranspiration and precipitation)and the area of shelter forests(P \ 0.0001), in which water conditions and the existence of shelter forests contributed49.7 and 12.8 % to total vegetation cover, respectively. The area of shelter forests increased sharply due to program efforts, but only shrub forests had significant direct effects on reducing the area of desertification categorized as slightly desertified. The reason for the lack of direct effect of increased arbor forests(accounting for 95.3 % of the total increase in shelter forests) on reducing desertification might be that the selected arbor species were not suited to water conditions(low precipitation, high evapotranspiration) prevailing at HSL. The establishment of shelter forests aided control of desertification in the HSL region, but the effect was less than expected. Effective control of desertification in the HSL region or other similar sandy areas will require greater improvements in vegetation cover. In particular,shrub species should be selected for plantation with reference to their potential to survive and reproduce in the harsh climatic and weather conditions typical of desertified areas.     

Composition and partition of biomass in a smith fir (<Emphasis Type="Italic">Abies georgei</Emphasis> var. <Emphasis Type="Italic">smithii</Emphasis>) timberline forest on the Sergyemla Mountain,southeastern Tibetan Plateau

The southeastern Tibetan Plateau has the highest timberlines in the world and climate change affects this area to a considerable extent.Quantification of vegetation biomass in the forests at the timberline is essential for understanding carbon balance,forest structure and functional changes in the forests at timberlines.We describe biomass and its constituent components of a smith fir timberline forest occurring at an elevation of 4320 m on the Sergyemla Mountain in the southeastern Tibetan Plateau.The results show that,in the tree layer,the average diameter at breast height(DBH) was 35.6 cm,the density 251 trees per hectare with a total biomass of 309.9 t.ha-1.Of the total biomass,the trunks accounted for 70.49%,branches for 9.09%,leaves for 5.57% and roots for 14.85%.The total biomass in the shrub layer was 77.9 t.ha-1 of which the biomass of trunks,branches,leaves and roots accounted for 42.8,14.9,4.6 and 15.6 t.ha-1,respectively.The total biomass in the herb layer was 3.0 t.ha-1.The total vegetation biomass in the smith fir timberline forest was 390.9 t.ha-1,to which the tree layer contributed the most(79.3%),followed by shrubs(19.9%) and herbs(0.8%).We estimate that the smith fir forest stand at the timberline had a higher total biomass than other fir or spruce forest stands in the surrounding area.     

Using multi-source remote sensing data to classify larch plantations in Northeast China and support the development of multi-purpose silviculture

Due to increasing timber demands, large areas of secondary forests have been converted to larch plantations(LPs) in Northeast China because the secondary forests could not produce timber as much as LPs.However, there are a series of ecological problems such as lower soil fertility, reduced water-holding capacity and acidification of surface runoff water occurring in LPs because of the single-species composition of LPs.Therefore, a guidance on how to transform LPs into larch-broadleaf mixed forests(LBMFs) at a large spatial scale is needed for local foresters.First, Landsat time series data set and SPOT-5 images were combined to map the spatial–temporal distribution of LPs in Northeast China.Then, the topographical characteristics of LPs in 2010 s were determined.Furthermore, three sub-regions of LPs were divided closely linking to their ecosystem services and forest management aims.Finally, detailed information on how to transform the LPs into LBMFs was given according to the three subregions.The results showed that the area of LPs increased during 1980 s and 2010 s, and reached 2.61 million ha in2010 s.Of which, 0.72 million ha(27.6%) and 1.89 million ha(72.4%) LPs distributed in slopes less than 5° and greater than 5°, respectively.Of the LPs(72.4%) in slopes greater than 5°, 48.7 and 23.7% located in downslope(LPs locating at the down slope of adjacent secondary forests in the same aspect) and upslope(LPs locating at the up slope of adjacent secondary forests in the same aspect), respectively; 0.10 million ha(3.8%) located in slopes greater than 25°.The LPs were divided into Sub-Regions-Ⅰ, Ⅱ, Ⅲ according to slopes.For Sub-region-I(top role is to produce timber), self-fertilizing shrub species can be introduced after clean cutting for young-aged LPs, and release thinning can be applied for middle-aged LPs, fast growth thinning for near-matured LPs, and clear cutting for matured LPs.For Sub-Region-Ⅱ(the priority is to provide water conservation combined with timber production), the LPs should be induced into LBMFs.The LPs located the downslope positions in Sub-Region-Ⅱ can be transformed to LBMFs by natural regeneration of broadleaved tree species after thinning because of enough seed sources of broadleaved tree species from the secondary forests locating the upslope positions.The LPs located the upslope positions or the region where seed sources of broadleaved tree species are unavailable in Sub-Region-Ⅱ must be induced to LBMFs by artificial regeneration.For Sub-Region-Ⅲ(the preference is only for water conservation because the slope is greater than 25°), the LPs should be particularly protected from intensive disturbances, and induced into LBMFs by natural regeneration.     

Active organic carbon pool of coniferous and broad-leaved forest soils in the mountainous areas of Beijing

In order to explore the effects of different forest types on active soil carbon pool, the amounts and density of soil organic carbon (SOC) were studied at different soil horizons under typical coniferous and broad-leaved forests in the mountainous area of Beijing. The results showed that the amount of total SOC, readily oxidizable carbon and particulate organic carbon decreased with increasing depths of soil horizons and the amounts at depths of 0–10 cm and 10–20 cm in broad-leaved forest was clearly higher than that in coniferous forests. The trend of a decrease in SOC density with increasing depth of the soil horizon was similar to that of the amount of SOC. However, no regular trend was found for SOC density at different depths between coniferous forest and broad-leaved forests. The ratio of readily oxidizable carbon to total amount of SOC ranged from 0.36–0.45 and the ratio of particulate organic carbon to total amount of SOC from 0.28–0.73; the ratios decreased with increasing depths of soil horizons. Active SOC was significantly correlated with total SOC; the relationship between readily oxidizable carbon and particulate organic carbon was significant. A broad-leaved forest may produce more SOC than a coniferous forest.     

Spatial Para Allocation of a Small Watershed Protection Forest System

With the interpreted IKONOS4 satellite images collected in 2005,a 1:10 000 forest map,the data collected in ClassⅡforest survey in 2007,and surface runoff data obtained in the permanent runoff monitoring station,six site factors of slope gradient, slope position,soil thickness,soil thickness of A layer,soil type and soil water content were selected to establish a matter element model suitable to 297 forest sub-compartments.Further,the AHP was applied to modify the spatial structure and form the spatial para allocation of the protection forest system. The results showed that:1) the area allocation of different vegetation types was irrational,the area of a mixed coniferous and broad-leafed forest was 124.39 ha,accounting for 14.97%of the forested land,the mixed forest was consisted of two coniferous species accounted for 27.37%of the total forest land,and the pure forest was consisted of one coniferous species accounted for 42.48%.2) After optimization,the area allocation of different vegetation types in the protection forest system ranked as:the mixed coniferous and broad-leafed forest(31.12%)>shrub land(15.5%)>the economic tree crops(12.28%)>the mixed forest consisting of two coniferous species(11.46%)>the pure broad-leafed forest(11.41%)>the pure coniferous forest(9.51%)>grass land(8.70%). Besides,the annual surface runoff could reduce 43 171 mm or 62.15%,annual soil erosion could decrease 465.97 t or 79.66%.3) The following suggestions for spatial para allocation of the small watershed protection forest system were proposed: (1) Reducing pure cypress or pine forest,and increasing alder-cypress,oak-cypress or pine-cypress mixed forest.As for the current cypress and pine pure forests,alder or oak could be introduced to develop a mixed forest.(2) The canopy closure of pure cypress forest and alder-cypress forests should be maintained within 0.60-0.75,and the canopy closure of oak-cypress,pine-cypress or oak-pine forests should be controlled within 0.60-0.80. (3) For improvement of current pure     

Forest cover change and its driving forces in Fagita Lekoma District,Ethiopia

This study investigated forest cover change and the driving forces behind it in Fagita Lekoma District of Ethiopia that resulted in increased forest cover, which might be uncommon outside this case study area. The LULC change analysis was made from 2003 to 2017 based on Landsat images. Socioeconomic analysis was carried out to identify the major driving forces that resulted in LULC change. A questionnaire survey, focused group discussion, key informant interviews and field observation were employed to analyze the link between LULC change and the driving forces. The 15-year period(2003–2017)image analysis revealed that the coverage of forest lands,built-up areas and grassland has increased by 256%, 100% and 96%, respectively, at the expense of cultivated lands and wetlands. The increased forest cover is due to the woodlots expansion of Acacia decurrens Willd, which are designed for sustainable livelihoods and a land revitalization strategy in the study area. Rapid population growth, an increasing demand for charcoal and subsequent market opportunities, preferred qualities of A. decurrens or black wattle to halt land degradation as well as to improve land productivity, have been identified as the major driving forces of forest cover change. Chi squared analysis revealed that: a comparative cash income from the sale of A. decurrens; a dependency on natural forests; the distance from the district administrative center; the size of the active labor force, and the area of land owned have significantly affected the cover change. The major forest cover change is due to the expansion of A. decurrens plantations that have socioeconomic and environmental implications to improve rural livelihoods and revitalize the land. Thus, the positive experiences identified in this study should be scaled-up and applied in other similar settings.     

Impact of mangrove vegetation on seasonal carbon burial and other sediment characteristics in the Vellar-Coleroon estuary,India

This work quantified the total carbon and 12 other sediment characteristics at 10 soil depths, in planted and or natural mangrove forests in comparison with non-vegetated soil for four seasons of the year 2009-2010 in the Vellar-Coleroon estuarine complex, India. The sedi- ment characteristics varied significantly between mangrove-vegetated and non-vegetated habitats or seasons of analysis, but not between soil depths. The mangrove sediments were rich in total carbon and total or- ganic carbon as compared to non-mangrove sediments （p 〈0.01）. Total carbon was 98.2% higher in mature mangroves and 41.8% in planted mangroves than that in non-mangrove soil. Total organic carbon was as much as 2.5 times greater in mature mangroves and 2 times greater in planted mangroves than that in unvegetated soil. Carbon contents also varied many fold by season. Total carbon content was 8.6 times greater during pre-monsoon, 4.1 times greater during post-monsoon and 2.5 times greater during monsoon than during summer （P〈0.01 in all cases）. Similarly, total organic carbon was 5.9 times greater during pre-monsoon, 3.1 times greater during post-monsoon and 69% greater during monsoon than during summer. In general, higher levels of sediment carbon were recorded during pre and post-monsoon seasons than during other seasons. Total carbon concentration was correlated negatively to temperature, sand and phosphorus （P 〈0.01）; positively correlated with redox potential, silt, clay, C/N ratio, potassium （P 〈0.01） and nitrogen （P〈0.05）; but not correlated with soil depth, pH or salinity. This work revealed that the carbon burial was rapid at the annual rate of 2.8% for total carbon, and 6.7% for total organic carbon in mangrove-planted sediment. Cleating of mangroves can result in significantly and rapidly reduced carbon stores.Our study highlights the importance of natural and plantation mangrove stands for conserving sediment carbon in the tropical coastal domain.     

Carbon stock measurements of a degraded tropical logged-over secondary forest in Manokwari Regency, West Papua, Indonesia

Several studies have been conducted in the past on carbon stock measurements in the tropical forests of Indonesia.This study is the first related research conducted in the New Guinea Island.In a degraded logged-over secondary forest in Manokwari Regency (West Papua,Indonesia),carbon stocks were measured for seven parts,i.e.,above-ground biomass (AGB),below-ground biomass (BGB),under-storey biomass (B u),necromass of dead leaves (N l),necromass of dead trees (N t),litter (L) and soil (S) using appropriate equations and laboratory analysis.Total carbon stocks were measured at 642.8 tC·ha-1 in the low disturbance area,536.9 tC·ha-1 in the moderate disturbance area and 490.4 tC·ha-1 in the high disturbance area.B u,N l and N t were not significant in the carbon stock and were collectively categorized as a total biomass complex.The carbon stock of litter was nearly equal to that of the total biomass complex,while the total carbon stock in the soil was eight times larger than the total biomass complex or the carbon stock of the litter.We confirmed that the average ratio of AGB and BGB to the total biomass (TB) was about 84.7% and 15.3%,respectively.Improvements were made to the equations in the low disturbance logged-over secondary forest area,applying corrections to the amounts of biomass of sample trees,based on representative commercial trees of category one.TB stocks before and after correction were estimated to be 84.4 and 106.7 tC·ha-1,indicating that these corrections added significant amounts of tree biomass (26.4%) during the sampling procedure.In conclusion,the equations for tree biomass developed in this study,will be useful for evaluating total carbon stocks,especially TB stocks in logged-over secondary forests throughout the Papua region.     

Structure and regeneration status of mangrove patches along the estuarine and coastal stretches of Kerala,India

This study presents the structural characteristics and regeneration potential of mangrove patches in the estuarine and coastal areas of Kerala, a tropical maritime state in India. Field surveys were carried out at 46 selected sites during August 2015 to May 2016. In each site, the vegetative structure and regeneration status were assessed using the quadrat method. Altogether 219 quadrates were laid out and a total of 13 true mangrove species, belonging to 5 families and 8 genera, were recorded. The total tree density and stand basal area of the study region was1678.08/ha and 20.33 m^2/ha respectively. The low basal areas indicate the reduced structural development in mangroves. Of the 13 tree species, Avicennia constitutes 56%of the total Important Value Index(IVI) and Avicennia officinalis represents 41% of the IVI in Kerala, followed by Avicennia marina(15%), Rhizophora mucronata(15%),Sonneratia alba(8%) Rhizophora apiculata(7%) and Excoecaria agallocha(7%). The diameter at breast height(DBH) in the study area revealed that 47% of the tree species came under the 1–10 cm DBH class. Total sapling and seedling density in Kerala was 2238.35 and 3232.42 individuals/ha respectively. Density of young plants(seedlings ? saplings) was only 31% greater of tree density and varied from 3–63%, which indicates poor regeneration potential. The Maturity index value(MIV) and complexity index(Ic) value of mangroves were 18.30 and 109.81 respectively. However, the low Ic value(\ 10) observed in seven out of ten coastal districts indicated poor structural development of mangroves in Kerala. Therefore, locationspecific conservation and management measures, guided by the knowledge on spatial distribution and habitat requirements of mangrove varieties should be taken to preserve the mangrove diversity of Kerala.     

Status of urban vegetation in Guangzhou City

According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species diversity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densities of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Comparing with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vecletation in order to improve urban eco-environment.     

广东沿海红树林的保护与发展

文章阐述了广东省沿海城市红树林资源的重要性、保护和管理历程及发展现状,提出红树林保护和可持续发展的建议。       

基于LUCC和景观格局变化的海南东寨港红树林湿地动态研究

目的 探究海南东寨港红树林湿地的动态变化,为推进红树林湿地保护、海岸带修复、退塘还湿等重大生态措施的开展提供理论参考。 方法 本研究从景观格局和土地利用两个层面描述东寨港地区红树林湿地的动态变化特征,通过结合土地利用/覆被变化（LUCC）和景观生态指数2种方法,探究红树林湿地动态变化。 结果 （1）从土地利用的角度看,1988—2016年间,研究区域养殖水面和建筑面积大比例增长,分别从占总面积的1.6%和1.86%,上升到11.89%和9.39%;林地和耕地面积相对减少,占比分别从17.61%和38.89%,下降到11.83%和27.06%;（2）从景观角度看,斑块密度和数量的上升、平均斑块面积的下降、面积加权平均形状破碎化指数的高位稳定等景观指标状态都显示东寨港地区在研究区间内景观破碎化程度正在逐渐加大;（3）景观破碎化指数与各景观类型面积变化的相关性分析结果表明,耕地面积的减少加上建筑用地和养殖水面面积的增加促使景观破碎化的加重;（4）红树林在整个研究区间内总面积未出现明显波动,与其它地类间的互动主要表现在耕地、养殖水面和水域之间的转换。 结论 东寨港红树林湿地在近30年间,发生了养殖水面和建筑面积的增长以及林地和耕地面积的减少等土地利用变化,而耕地面积的减少,建筑用地和养殖水面面积的增加促使景观破碎化加重。     

中国热带次生林分布、类型与面积研究

热带林的保护问题已受到世界各国的高度重视,由于占世界热带林面积约三分之一的热带次生林,其经济和生态效益通常较差,处于相对被忽视的状态,因此也往往被进一步破坏。将次生林经营纳入可持续经营的轨道,是实现热带林可持续经营目标的重要战略。通过对中国热带森林研究、经营和统计资料的分析,结合本项目实施过程的实地调研取得的结果,文章对中国热带地区次生林分布、面积和类型作了阐述。热带森林主要分布在海南、广东、广西、云南、台湾,以及福建和西藏的部分地区,包括124个县市的全部和50个县市的部分地区。据可认可的资料统计,中国热带林地面积（不含台湾省）约1125．66万hm^2。其中有林地面积1074．49万hm^2,次生林面积544万hm^2。次生林占热带地区林地面积的48．33％,占有林地总面积的50．63％。中国热带林地和次生林的实际数字估计要比这一数值大6％以上,因为中国这几年高度重视林业建设,森林植被特别是热带森林植被恢复得很快,林地和次生林一直在不断增加。热带森林类型主要有：热带雨林（包括湿润雨林、山地雨林）;热带季雨林（包括半常绿季雨林、落叶季雨林、石灰岩季雨林）;南海珊瑚岛植被;海岸红树林等。从森林经理的角度,中国热带次生林的类型可分为：（1）次生阔叶林,包括次生常绿阔叶雨林、次生季雨林和次生季风常绿阔叶林;（2）次生灌木林;（3）次生针叶林;（4）次生红树林及次生珊瑚岛林等四大类型。     

Conversion and recovery of Puerto Rican mangroves: 200 years of change

Human activities have dramatically reduced the world’s area of mangroves just as the ecological services they provide are becoming widely recognized. Improving the conservation tools available to restore lost mangroves would benefit from a better understanding of how human activities influence the conservation of these ecosystems. We took advantage of historical information and long-term landscape analyses to relate land use change with the area of mangroves in Puerto Rico. We found that mangroves experienced dramatic changes over the last 200 years, and four distinct eras of change were visible. During the agricultural era (1800–1940) the area of mangroves declined 45%. As the economy changed to industrial in the late 1940s the area of mangrove increase due to reduced land use pressure on the wetlands. Nevertheless, urban expansion between 1960s and 1970s produced another decline. Public concern for mangrove conservation resulted in the legal protection of all the mangroves in 1972, and since then their area has expanded. We found that past human activity altered the original proportion of mangrove species. The number and size of mangrove-forest fragments was impacted by land use, and urban areas had fewer and smaller fragments than vegetated areas. Uncontrolled expansion of urban areas emerged as a major threat to mangrove conservation. Mangroves are resilient and recover quickly when given an opportunity if the geomorphological and hydrological features of the habitat are not changed by their use. The key to conservation appears to be a combination of the type of human activity in mangrove watersheds combined with strong legal protection. The following steps are recommended: (1) identify the areas that satisfy the ecological requirements of mangrove development; (2) incorporate better zoning regulations to maintain these areas natural and to protect the fluxes of water, nutrients, and organisms in and out of the system; and (3) monitor results.     

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 hm2,其中,红树林有林地有400.15 hm2,红树林未成林造林地有42.27 hm2,红树林宜林地有919.41 hm2;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....     

广东省红树林生态系研究展望

广东省是我国红树林分布面积最大和台风多的省区,也是国际候鸟迁徙路线上停歇和越冬的主要站点,在减灾防灾、生物多样性和污染物生态修复等方面有极其重要的研究意义。因此,广东省红树林生态系研究要着重解决广东省现有红树林的生物多样性调查、生态功能评估、生态系统经营、大量红树果实加工利用、沿海困难滩涂与堤岸红树林营造等技术问题,为其红树林生态系恢复与管理及其红树林生态系资源的可持续利用提供技术支撑。     

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.     

论中国林木引种驯化策略

林木引种驯化已经成为现代林业的重要组成部分。从现代林木引种驯化概念出发，对林木引种驯化策略进行了探讨分析，对于中国林业的持续发展，在理论和实践上都是十分必要的。     

广东省森林资源及碳储量分布

利用2009年广东省森林资源监测数据,研究广东省森林资源和碳储量分布。结果表明,2009年广东省森林资源中2／3是商品林,并以一般用材林为主,速生林（含短轮伐期）的比例不到1／5,生态公益林的面积占林业用地面积1／3;各区域的森林资源中均以商品林为主,占64.7％～73.7％。商品林中除其他区域外均以一般用材林为主,占商品林面积的59.8％～81.3％,而其他区域以速生林为主。广东省的森林碳密度为32.2t／hm^2,其大小呈现粤北〉其他〉粤西〉珠三角〉粤东,森林碳储量为302.3TgC。     

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。