海南省沿海防护林防护效能综合评价研究

建立了海南省海防林防护效能的评价指标体系和评价标准,通过案例分析对熵权法、主成分分析和层次分析赋权方法进行了选优,确定层次分析法(AHP)更适合海防林防护效能的综合评价,同时通过聚类分析进一步验证了评价标准和评价权重分配的有效性。用层次分析法对文昌、万宁和昌江3个县市的海防林进行了6因素25个评价指标和沿海12个市县海防林5因素17个评价指标的综合评价,结果显示:在海防林的防护效能方面文昌海防林达到了良好水平,万宁为中等水平,昌江为不合格;沿海12个市县中,有6个市县的评价分值未达到合格标准,占评价单位的50%,2个评价单位达到了良好标准,占17%,2005年海南省海防林整体防护效能不高。     

沿海防护林防护效能的综合评价

建立海南省海防林防护效能的评价指标体系,对主客观综合评价方法和赋权方法进行分析,并应用层次分析法(AHP)对文昌、万宁和昌江的沿海防护林进行综合评价.评价结果显示:在海防林的防护效能方面万宁好于文昌,文昌好于昌江;万宁海防林长势良好,林带结构相对完整,但林分结构不够理想;文昌海防林龄级结构分布合理,群落层次结构复杂,林种配置合理,但林分长势较差;昌江海防林林分结构相对最好,但林带完整度不高,树种单一,群落层次简单.     

海南省制订措施推进沿海基干林带建设

长期以来,海南省一些地区对沿海基干林的作用认识不足,沿海基干林屡遭破坏,导致248公里基干林带断裂,加上多年来的台风袭击造成了550公里林带断梢枯死、林相残缺不全,海南沿海基干林带防护效能日渐衰退。针对这一严峻问题,我省制订了强有力的应对措施,决定用3年时间把毁坏的海防林恢复和建设起来。一是明确任务,落实责任。2007~2009年全省将新造、改造海防林20.9万亩,海南省政府将把海防林建设列入与市县政府签订的《发展森林资源目标管理责任状》内容,并进行年终考核。各市县政府要成立海防林建设工程领导小组,建立沿海防护林建设目标管理…     

海南省文昌与万宁沿海防护林质量调查与对比分析

为了解海南省海防林现状，对文昌和万宁两地海防林进行了大范围的踏查和典型抽样调查，共计调查了37个临时样地。调查分析结果显示：（1）文昌与万宁海防林在龄级结构、群落层次结构，生长状况，林分密度，海防林模式等方面存在一定的差异；（2）文昌海防林龄级结构合理，群落层次较复杂，海防林模式多样化，但枯梢、枯死现象严重；（3）万宁幼龄林比例高，群落层次相对简单，滥伐现象较普遍，但林分长势良好；（4）文昌与万宁具有防护性能的海防林密度低，林分稀疏，具有良好防护性能的海防林不足25％。     

省林业局加快步伐,海防林建设又有新部署

海南省林业局提出,省委、省政府决定用3~5年时间恢复海防林的重大部署,是我省历史上规模最大、影响最深的全省性统一行动.领导重视,百姓关心,社会关注,是生态立省的一件大事。海防林建设不只是补补缺口的问题,还要改善林相、优化结构、提高质量,把海防林建设成为一道亮丽的风景线。省林业局对当前海防林建设工作进行了新的部署:一、立即组织海防林工作组赴市县。从省局机关、省森林资源监测中心和省林科所组织干部和专业人员,成立工作组分赴12个沿海市县开展工作。要求工作组一定要纪律严明,高度负责,认真督导,切实按照省领导的部署,逐个市…     

构筑绿色长城，我省全面拉开建设海防林序幕

在2007年6月1日召开的全省海防林建设动员大会上，省委、省政府向全社会发出了“筑我绿色长城，护我宝岛家园”的号召。会上，省长罗保铭、副省长陈成与海口、三亚、临高等12个沿海市县的市县长签订了《海南省沿海基干林林带建设目标管理责任状》，根据海防林建设规划的面积，限定了具体任务和时间，明确了责任追究制度，海南省千里海防林建设就此拉开序幕。     

沙岸黑松海防林防护成熟期及更新年龄的研究

在对山东省黑松海防林进行全面踏查的基础上，应用典型调查和定位观测相结合的方法，开展了沙体岸黑松海防林的调查研究。采用数量化理论Ⅰ的方法，对黑松海防林立地质量进行了数量化评价，划分出11种立地类型；并采用系统聚类法，将研究区的黑松海防林划分为3种林分生长类型；其中生长类型Ⅰ的林分生长表现最好，生长类型Ⅱ的次之，生长类型Ⅲ的最差。在综合分析黑松海防林防护成熟和数量成熟的基础上，提出黑松海防林的防护成熟期；生长类型Ⅰ为33-57a，生长类型Ⅱ为14-32a，生长类型Ⅲ为13-28a；确定黑松海防林的更新期；生长类型I为33-57a，生长类型Ⅱ为23-32a，生长类型Ⅲ为21-28a；确定黑松海防林的合理更新年龄；生长类型Ⅱ为32a，生长类型Ⅲ为28a。     

保定市生态景观林评价指标体系研究

通过借鉴国内外有关生态景观林评价体系的研究成果与实践,在综合河北省现有生态景观林类型与构成的基础上,从生态景观林的防护功能、景观生态功能、景观美学功能、文化功能、社会经济功能5个方面出发,构建了一套生态景观林评价体系。本研究采用专家评分法和层次分析法(AHP)结合保定市的生态景观林的实际应用,对评价指标赋予权重值,并对保定市的生态景观林进行评价,从而为生态景观林的建设提供了一定的参考依据。     

海南省海防林研究

海南四面环海,海防林体系在防风和抵御海啸等方面作用巨大,加强海防林建设,构筑良好的生态屏障,是海南生态环境建设的重要内容,同时,海防林体系建设还能给海南提供巨大经济和社会效益,保护和建设海防林对海南省经济社会建设具重大意义。近年来,由于人们过于片面追求经济利益,海南省海防林屡遭破坏,保护和建设海防林已成为海南省当前的首要任务。     

中国东南沿海混交海防林建设研究进展

综述了我国东南沿海混交海防林的现状,目前混交林型海防林主要是木麻黄与湿地松、相思类树种与桉属等树种混交形成的混交林。通过分析比较不同混交林型的生长效果、防护效能和改土效果,提出合理的混交类型。此外还提出采用乡土树种与木麻黄混交,为建设混交林型的海防林体系提供更多的混交树种选择,为我国沿海防护林的管理、低效林的改造以及提高海防林的生态功能提供参考。     

Protection efficiency assessment and quality of coastal shelterbelt for Dongshan Island at the coastal section scale

The coastal shelter forest in China is under threat of destruction and degradation because of the impact of human activities. Protection efficiency assessment of the coastal shelterbelt is an important component of shelter-forest remediation planning and sustainable management. In this study, a protection efficiency index (PEI) model was established using the projection pursuit method to assess the protective quality of the coastal shelter forest at the coastal section scale of Dongshan Island, China. Three criteria were used, including forest stand structure, forest belt structure, and windbreak effect; each criterion further comprised multiple factors. Based on survey data of 31 plots in the coastal shelter forest of Dongshan Island, we calculated PEI values using a projection of a pursuit model. The result showed 64.5 % of the PEIs fell at or below the middle level, which can indicate the status of the coastal shelterbelt is unsatisfactory. To further explore whether the different bays and land use types create significant differences in PEIs and evaluation indices, we used an ANOVA to test the influence of various bays and forms of land use on coastal shelterbelts. The results showed that PEI and most of the indices differed significantly by bay; mean tree height, mean DBH, mean crown width, stand density, vegetation coverage, and wind velocity reduction differed significantly by land use. Therefore, relevant measures for different locations, bays and surrounding land use can be proposed to improve the existing conditions of the coastal shelterbelt. The results of this study provide a theoretical and technical framework for future changes and sustainable management of coastal shelterbelt on Dongshan Island.     

农业科技110绩效评价分析——以海南省为例

指出了农业科技110是海南省农业科技推广的主要模式,对于其绩效评价的分析有助于更好地发展海南特殊的热带高效农业资源。对海南省18个市县36个乡镇的农业科技110服务站工作具体开展情况做了调研,利用国内目前比较前沿的绩效评价分析方法DEA方法实证分析评价了海南省农业科技110的绩效情况,对海南省农业科技110的发展提出了政策建议。     

Effects of species and shelterbelt structure on wind speed reduction in shelter

Live shelterbelts are common elements in coastal land areas and play an important role in reducing wind speed and sand drift. A simple measured index, that well represents relationship between shelterbelt structure and wind speed reduction, is required by landowners to enable them in establishing more effective shelterbelts. A three-dimensional crown (3D) density is proposed, which can be easily identified through shelterbelt parameters including maximum height, shelterbelt width, vertical crown/stem area ratio, and horizontal crown/stem area ratio. The utility of the index was tested in 10-year-old Casuarina equisetifolia and in 7-year-old Acacia auriculiformis shelterbelts in north central Coast of Vietnam. There was a significant negative linear relationship (R ² = 0.64, p < 0.001) between 3D density and wind speed reduction efficiency, while there was no relationship between a two-dimensional crown density and wind speed reduction efficiency. Reduction efficiency was found to increase at higher wind speeds in shelterbelts of A. auriculiformis, but not C. equisetifolia. The A. auriculiformis shelterbelt was more efficient in reducing wind speed compared to C. equisetifolia shelterbelt. The former recovered 70 % wind speed at 130 m (16.5H) leeward, while it recovered 70 % at 85 m (8H) leeward in C. equisetifolia shelterbelt.     

东北平原农田防护林规格的研究

东北平原农田防护林已经形成了比较完整的林网体系。本研究分析了农田防护林网全方位的防风作用、防霜作用以及林网内的综合气候效益场。在林网内,全方位防风效能大于10%的区域为防护效益区。作物产量和质量分析表明,林网的防护范围为25倍树高。根据高生长分析确定了构成农田防护林主要杨树品种的成林高度。根据综合分析确定适宜农田防护林网的规格为400m×400m。图7表3参11。     

Remote estimation of shelterbelt width from SPOT5 imagery

Width is one of the key parameters of a shelterbelt. Traditional methods to acquire this width are mainly based on field measurement, which is impractical for monitoring shelterbelts at regional scale. There are many studies analyzing linear objects, but they are not directly applicable to width detection of such objects. In this paper, we analyzed relationships among vegetation fractions retrieved from SPOT5 remote sensing imagery with 10 m × 10 m spatial resolution, shelterbelt area, and shelterbelt width in one pixel. Based on this analysis, we developed a method for recognizing shelterbelt width from a remote sensing image of central western Jilin Province, China. The result was validated by field measurement data and measurement from an aerial image of 0.5 m × 0.5 m spatial resolution. Mean absolute error was 2.40 and 2.73 m respectively, suggesting that the proposed method is feasible and its accuracy is acceptable. The study provides a valuable method for monitoring shelterbelt width across large spatial scales and an accurate input parameter for the recognition of shelterbelt porosity from remote sensing data in future research.     

A retrieval and validation method for shelterbelt vegetation fraction

Shelterbelts are important in defending against natural disaster and maintaining ecological balances in farmland. Understanding of the shelterbelt vegetation fraction is fundamental to regional research of shelterbelts using remote sensing. We used SPOT5 imagery with 10×10m spatial resolution in combination with knowledge of the characteristics of shelterbelts to develop a method for retrieval of the vegetation fraction of shelterbelts by the pixel un-mixing model. We then used the method to retrieve values for shelterbelts in study area. By combining the parameters of photographic images with characteristics of shelterbelts, we developed a method for measuring the vegetation fraction of shelterbelts based on an advanced photographic method. We then measured the actual values to validate the retrieval result. The multiple correlation coefficients between the retrieved and measured values were 0.715. Our retrieval and measuring methods presented in this paper accurately reflect field conditions. We suggest that this method is useful to describe shelterbelt structure using remote sensing.     

福建沿海地区木麻黄迹地更新问题研究

针对福建沿海地区木麻黄迹地更新难的问题,在平潭县芦洋农场进行了农地与迹地营造木麻黄防护林带更新试验,根据两带木麻黄生长情况,从土壤机械组成、化学基本组成以及土壤微量营养元素与木麻黄小枝微量营养元素铜、锌、硼、钼的含量进行分析比较,结果表明:长期种植木麻黄迹地的酸性沙质土,土壤中有效钼长期消耗,造成土壤有效钼的缺乏,是迹地木麻黄生长不良的重要因素。     

山西北部农田防护林的防风功能及结构研究

山西北部地区处于毛乌素沙漠前沿,是暖温带落叶阔叶林向温带干旱草原的过渡带。20世纪50-60年代当地营造了大面积的小叶杨(Populus simonii)人工林,形成了以林网为主体的农田防护林体系,对防治农田土壤风蚀起到了重要的作用。近年来,在旧林带更新改造中,对林带结构、树种配置缺乏技术,表现出在营造林带中有较大盲目性。为了对防护林今后的发展提供科学依据和方法,1996-2001年作者在山西北部的朔州、大同等地设置了定位调查观测点,使用轻便式风速风向仪、通风干湿球温度计、地温计、玻璃皿对小叶杨不同结构林带的防风功能进行了调查研究。提出了农田防护林的设计应以树木展叶期的防风能力为指标,以疏透结构为最佳配置,初植株行距为2 m3 m,4-6行配置,5年后可形成疏透结构林带。表4参13。