广东省石漠化现状与治理对策

摘要：采用遥感影像和GPS实地勾绘图斑、结合地面调查方法和GIS技术对广东省岩溶地区石漠化进行监测,描述了全省石漠化面积和程度分布,分析了石漠化的分布特性与动态变化,提出了石漠化防治相应对策,为全省石漠化防治提供可供参考的技术途径。     

云南省岩溶地区石漠化现状、成因及防治对策

云南省石漠化土地占全省岩溶面积的25.99%,占总土地面积的7.31%,文山州、曲靖市、昭通市为云南省石漠化最为严重地区。全省石漠化分布主要以中度石漠化为主,其次为轻度石漠化,中轻度石漠化所占比例为78.22%。文中针对云南省石漠化的现状、成因机理及危害特点,提出了石漠化防治对策和建议。     

石漠化现状与对策研究——以威宁县为例

分析了威宁县石漠化现状和分布特点，提出威宁县石漠化治理防治措施、治理对策和模式。     

云南石漠化的生态特征及其危机表现

云南是我国岩溶石漠化严重的省份之一，全省63个县分布有石漠化土地2．149万km^2。论述了石漠化的生态特点及其脆弱生态结构的表现。石漠化治理已迫在眉睫。     

我国石漠化现状与防治对策

论述了我国石漠化现状、分布特点及成因,提出了林业在石漠化防治中的对策,旨在为科学防治石漠化和制订相关政策提供参考。     

湖南将加快石漠化综合治理步伐

在湖南省石漠化综合治理现场会上，副省长强硕辅提出要求：加快石漠化综合治理步伐，到2015年，全省80个县（市区）的石漠化区域要恢复或重建生态系统。湖南省石漠化面积达15万平方公里，排全国第四位，主要分布在湘西、湘南岩溶地区。过去5年，全省仅对31个县（市区）802平方公里石漠化进行了治理，治理面积仅为S3％。张硕辅强调，开展石漠化综合治理，加强植被恢复是基本出发点，改善水保状况是重要手段，提高圈养能力是可靠保障。各级要增强责任感、使命感和紧迫感，把石漠化综合治理向纵深推进。石漠化地区的各县（市区）要加强资金整合使用，确保石漠化综合治理的资金投入。     

云南省岩溶地区典型石漠化治理模式及评价

云南省是全国岩溶分布最广、石漠化危害程度最深、治理难度最大的省区之一。自2008年以来,云南省在石漠化较为严重的区域陆续开展了石漠化防治工作,取得了一定的成效。文章通过收集、整理、分析各治理县多年来石漠化防治方面的资料,结合石漠化土地分区,从中提炼出一些行之有效的、成功的、具有区域代表性的典型石漠化治理模式,希望对今后的石漠化防治工作起到借鉴作用。     

我国岩溶地区石漠化土地现状及主要分布特征

为提升石漠化调查成果数据共享应用水平，通过深度挖掘第四次石漠化调查数据，分析了截至2021年底我国石漠化土地现状及分布特征，得出以下结论：(1)我国石漠化土地主要分布在南方热带亚热带、湿润半湿润岩溶地区，涉及10个省(市)的508个县(市、区),该区域是长江和珠江的重要水源涵养区、珠江发源地和我国南方重要的生态安全屏障；(2)石漠化程度以中度、轻度为主；(3)石漠化区林草植被中灌草覆盖占比高，林草植被质量不高，巩固治理成果压力大；(4)石漠化分布区的人地矛盾突出，巩固脱贫成果压力大；(5)潜在石漠化土地面积大，潜在风险高。以上分析结果可为石漠化防治政策制定与科学推进石漠化综合工程提供数据支撑。     

建始县岩溶地区石漠化现状与防治对策

笔者通过对建始县岩溶地区石漠化现状进行分析,针对本县石漠化土地的分布与特点,提出了具体的防治对策和建议。     

云南的石漠化土地及其治理策略

云南省有岩溶分布的县 115个 ,其中 6 3个县分布有石漠化土地 ,面积 2 14 9万km2 ,占全省国土面积的5 5 % ,石漠化地区生态环境恶化 ,自然灾害严重。近 5年来经多方治理取得了一定的成效 ,对今后石漠化土地的治理提出了若干建议。     

侧柏幼树覆盖试验

在太行山南部石灰岩中山区,以侧柏2年生幼树为研究对象,选择地膜、生态垫、秸秆、石块等材料进行覆盖保墒试验,用EM50自动测定土壤含水量,在生长期结束后对侧柏地径、苗高、生物量、成活率进行调查。试验结果表明:覆盖石块、渗水地膜能起到明显的保墒作用,茎、叶、总生物量、幼树高生长量明显高于其他处理,地径、主根、侧根的生长受影响不大。     

影响广东省石灰岩地区造林成活率的因素分析

石灰岩地区造林成活率低导致多年造林不见林 ,严重阻碍石灰岩地区绿化进程和经济发展。对石灰岩地区造林绿化现状调查 ,运用全面质量管理的理论和原理 ,采用PDCA循环工作法 ,分析导致石灰岩地区造林成活率低的各种因素 ,并提出对策措施。     

侧柏、油松幼苗水分胁迫试验

在太行山石灰岩中山区,以侧柏、油松2年生苗为研究对象,选择地膜、石块等材料覆盖,进行水分胁迫试验,每天3次用TDR测定土壤含水量,记录苗木严重萎蔫时的时间。结果表明:地膜覆盖盆植侧柏苗各层土壤温度均高于对照,而在生态垫覆盖下均低于对照;两种覆盖处理均能明显增加侧柏苗的土壤体积含水量,且延长侧柏苗存活天数10 d以上;覆盖处理盆植油松苗各层土壤温度与对照间均无显著差异;地膜和生态垫覆盖下油松苗的土壤体积含水量显著高于对照,石块覆盖下的土壤体积含水量与对照间无显著差异;地膜、生态垫、石块覆盖的油松幼树存活天数明显长于对照,以地膜覆盖延长的时间最多;侧柏苗和油松苗的致死土壤体积含水量分别为6.7%和7.8%。     

桂西南珍稀濒危植物区系的研究

桂西南属北热带气候区，面积4．8万km^2，约占全国土地面积的1／200，占广西土地面积的21％，区域内裸露岩溶面积约占50％，。自然分布的国家级珍稀危树种74种，占我国珍稀濒危树种的22．8％，占广西115个珍稀频危树种的64％。其中，龙州一个县分布的珍稀频危树种高达49种，约为全国珍稀频危树种的15％，为广西珍稀濒危树种的42．6％，是全国罕见的珍稀濒危树种荟萃之地。这一地区珍稀濒危树种的植物区系、有独特的地区性、区域内特有的树种明显；有滇、缅、泰地区成分，也有海南地区成分，成为两大地区植物区系交汇之地；更有泛地带性的多种植物，分布有南亚热带、中亚热带、北亚热带以至少数分布暖温带的珍稀濒危树种。研究这一地区珍稀濒危植物区系,大学术、科研以及对珍稀频危树种的保护、发展与利用等方面，均有重要价值。     

Resistance against oxidative stress in leaves of young beech trees grown in model ecosystems with different soil qualities, elevated CO2, and lachnid infestation

Summary The aim of the present study was to investigate whether the resistance of beech foliage(Fagus sylvatica) against oxidative stress was affected by soil quality, nitrogen or CO₂ fertilisation, or lachnid infestation(Phyllaphis fagi). For this purpose young beech trees were grown for four years in reconstructed calcareous or acidic forest soils in open top chambers under ambient or elevated CO₂ concentrations with two levels of nitrogen fertilisation. At harvest lachnid colonisation was observed, preferentially on leaves from trees in calcareous soil and on leaves from trees fertilised with the high nitrogen level. General leaf characteristics such as pigment concentrations, dry mass, and leaf mass ber area were not affected by the soil type, nitrogen fertilisation or CO₂ regime. Leaves colonised with lachnids displayed slightly increased leaf mass per area. When the stress resistance was challenged by exposure to paraquat — a herbicide inducing oxidative stress — leaves from trees grown on calcareous soil maintained significantly longer membrane integrity and, thus, were better protected against stress than leaves from trees on acidic soil. Other experimental variables had negligible or no effects on the resistance against oxidative stress.      

Development of Quercus ilex plantations is related to soil phosphorus availability on shallow calcareous soils

The objective of this study is to analyse the performance of Quercus ilex plantations established under semiarid conditions on different soils formed on calcareous and gypsiferous parent material. We studied eighteen 300?m² plots in which 1?year-old seedlings had been planted after subsoiling on the contour. Plots were stratified according to aspect (north and south) and previous land use/parent material: shrubland on limestone (LM-SH), shrubland on gypsum rock (GY-SH), and cropland on colluvium (CO-AG). Soils developed on limestone and colluvium had average rooting depths of 27 and 37?cm, respectively, and mean concentrations of active lime and phosphorus (P) of 130 and 190?mg?g^?1 and 10 and 19?mg?kg^?1, respectively. Soils developed on gypsum had a mean rooting depth of 26?cm, and a mean gypsum concentration of 73?%. Height and diameter of trees varied significantly according to parent material/previous land use but not to slope aspect. Mean height and diameter of trees were significantly higher in CO-AG plots than in LM-SH and GY-SH plots. Soil P and depth were the main variables explaining differences in dominant height across all 18 plots. In CO-AG plots mean height was negatively related to soil pH but positively related to soil P concentration. In LM-SH plots, mean diameter and height were negatively related to active lime concentration. This study suggests that soil P is a major determinant of holm oak performance in shallow calcareous soils and highlights the importance of conducting detailed soil studies in order to assess the viability of plantations with this species.     

Assessment of the impact of forest harvesting operations on the physical parameters and microbiological components on a Mediterranean sandy soil in an Italian stone pine stand

Forest harvesting operations may have a significant impact on soil physical properties by reducing its porosity and organic functions. Soil variations, in particular bulk density and total porosity, caused by external perturbations as soil becomes compacted due to machinery passes, can lead to changes in biogeochemical cycles that have consequences on soil ecosystems. This study investigated how the impact of forest operations and the elapsed time from harvest can influence: (1) the physical–chemical characteristics of soil and (2) the nitrogen-fixing and nitrifying microbial communities. The study area is located inside the Regional Park of Migliarino, San Rossore, Massaciuccoli (Pisa, Italy). In the study area, the soil has been classified as recent sands with sandy loam texture and slightly calcareous (USDA Soil Taxonomy classification). Soil samples were collected in patchy cut areas (strip cut) of Pinus pinea stand that was harvested in two steps: half area in 2006 and the rest in 2011. Soil samples were collected also in a control area (not harvested) with similar stand and soil characteristics. Statistical analysis was preceded by a test of normality (Kolmogorov–Smirnov test) and a variance homogeneity test (Levene’s test). Considering the dependence of the variables studied (physical and chemical soil characteristics), a MANOVA test and a post hoc Tukey HSD test were applied to determine statistical difference among the three treatments: harvested 2006, harvested 2011 and not harvested. The results did not indicate significant variations to the parameters of shear and penetration resistance, though soil bulk density and total porosity were significantly altered in the short period since forestry operations occurred. These physical changes induced qualitative (presence/absence and number of species) and quantitative (abundance and spatial evenness of the species) variations in the nitrogen-fixing and nitrifying microbial communities.     

不同土壤条件对槐树生长和生物量的影响

对4种不同土壤(水稻土、棕色石灰土、沙土、旱地土)中槐树幼苗的生长、生物量分配进行比较研究。结果表明:在槐树的生长量和生物量方面,棕色石灰土、水稻土与旱地土、沙土间均有显著差异,其大小顺序是:株高为棕色石灰土水稻土旱地土沙土;地径为水稻土棕色石灰土旱地土沙土;生物量为棕色石灰土水稻土旱地土沙土。表明棕色石灰土和水稻土比较适合槐树生长。     

徐州地区石质边坡生态植被恢复工程设计研究

随着我国城市化进程的日益加快,原有的荒山和采石场按现代城市发展的诉求,已纳入到城市新区、都市风景区、生态保护区的发展建设范围之中。那些历史上因破坏性开采形成的废弃采石宕口,惨然暴露在现代城市之中,成为一个个"伤疤",严重毁坏了城市的形象,影响了都市人居环境与自然的和谐发展。徐州石质边坡复绿工程的设计研究与成功经验,将为我国北方地区大型石质边坡复绿工程的实施提供参考。