游客需求的城市森林公园游憩空间选择

城市森林公园游憩空间需要合理规划设计,在保护生态环境的同时,满足广大居民的休憩游览等要求。通过问卷调查,研究游客对于城市森林公园游憩空间选择需求情况,以及影响游客对于城市森林公园游憩空间选择的影响因素;通过对于数据的分析,提出城市森林公园游憩空间有关问题和解决建议:加强游憩空间对于游人的吸引力度;游憩空间环境对于游人的影响;游憩空间设施对于游人的影响。     

古田县园地土壤氮磷钾与有机质相关性研究

福建古田县既是国家商品粮基地县,又是水果大县.水果为本县经济支柱产业.园地土壤是果树生长的基础,作物生长所需的营养70％来源于土壤,研究了解园地作物土壤养分状况是保证农业可持续发展的根本.因此,掌握古田县园地土壤养分状况与土壤养分空间分异规律,对本地区园地作物的配方施肥,提高作物产量与品质,增加果农收入及改善土壤环境等具有重要的现实意义.     

阿拉善荒漠区蒙古扁桃的种群龄级结构与空间分布格局

根据样地调查数据,编制了阿拉善荒漠区敖隆敖包及乌兰腺吉蒙古扁桃种群静态生命表,并由此求得蒙古扁桃种群大小级结构图、存活曲线及死亡率曲线,从而对两地蒙古扁桃种群空间分布格局进行了比较研究。结果表明,两地蒙古扁桃种群幼龄和老龄级个体较少,中龄级个体较多。总体上,敖隆敖包蒙古扁桃种群年龄结构呈稳定型,而乌兰腺吉种群趋向衰退型。两地存活曲线处于DeeveyⅡ和DeeveyⅡ2。两地种群空间分布格局均呈聚集型分布。分析表明,草畜平衡在蒙古扁桃种群稳定型中发挥着重要作用。     

基于绿色健身新模式的城市体育公园空间景观营造研究——以晋中体育公园空间景观设计为例

绿色健身空间将人们的健身活动融入了自然环境的美妙景观中,能够达到绿色生态健身的效果。笔者以晋中体育公园的空间景观营造为例,在分析了体育公园空间景观营造原则和设计目标的基础上,重点针对体育公园的体育文化内涵营造进行探讨,提出了城市体育公园空间景观营造的方法。     

A preliminary evaluation of throughfall sampling techniques in a mature coniferous forest

Rainfall, throughfall and stemflow were measured and canopy interception loss was derived for 14 rainfall events from June 22 to August 30, 2008 within a mature declining hybrid white spruce(Picea glauca(Moench) Voss × P. engelmannii Parry ex Engelm.)- subalpine fir(Abies lasiocarpa(Hook.) Nutt.)- lodgepole pine(Pinus contorta var.latifolia Dougl. ex Loud.) stand in south-central British Columbia, Canada. Stemflow was negligible during the study period, while, respectively throughfall and canopy interception loss accounted for approximately59.4% and 40.6% of the 50.1 mm of cumulative rainfall. Throughfall variability was assessed with three approaches involving roving and stationary wedge-type gauges, and stationary trough gauges. Throughfall exhibited large spatial variability with the coefficient of variability of study period throughfall sampled using 16 stationary trough gauges being30.3%, while it was 38.0% and 28.7% for 32 stationary and 32 roving wedge gauges, respectively. Our analysis suggests that a roving gauge method is better than a stationary approach since the errors associated with event mean throughfalls are summed quadratically and a greater portion of the canopy area is sampled. Trough gauges were more efficient than wedge gauges; however, this efficiency was less than expected given their much larger sampling areas, suggesting that spatial autocor-relation lengths of throughfall may be longer than the trough systems. The spatial distribution of throughfall showed a high degree of temporal persistence throughout the study suggesting the existence of stable "wet" and "dry" inputs to the floors of these coniferous forests.     

Spatial heterogeneity of factors influencing forest fires size in northern Mexico

In Mexico, forest fires are strongly influenced by environmental, topographic, and anthropogenic factors. A government-based database covering the period 2000-2011 was used to analyze the spatial heterogeneity of the factors influencing forest fire size in the state of Durango, Mexico. Ordinary least squares and geographically weighted regression models were fit to identify the main factors as well as their spatial influence on fire size. Results indicate that fire size is greatly affected by distance to roads, distance to towns, precipitation, temperature, and a population gravity index. The geographically weighted model was better than the ordinary least squares model. The improvement of the former is due to the influence of factors that were found to be non-stationary. These results suggest that geographic location determines the influence of a factor on fire size. While the models can be greatly improved with additional information, the study suggests the need to adopt fire management policies to more efficiently reduce the effect of anthropogenic factors. These policies may include more training for landowners who use fire for clearing, closure of roads, application of thinning, prescribed burning, and fire breaks in perimeters adjacent to roads.     

Developing a dynamic growth model for teak plantations in India

Background： Tectono grandis （teak） is one of the most important tropical timber species occurring naturally in India. Appropriate growth models, based on advanced modeling techniques, are not available but are necessary for the successful management of teak stands in the country. Long-term forest planning requires mathematical models and the principles of Dynamical System Theory provide a solid foundation for these.
Methods： The state-space approach makes it possible to accommodate disturbances and avarying environment. In this paper, an attempt has been made to develop a dynamic growth model based on the limited data, consisting of three annual measurements, collected from 22 teak sample plots in Karnataka, Southern India.
Results： A biologically consistent whole-stand growth model has been presented which uses the state-space approach for modelling rates of change of three state-variables viz., dominant height, stems per hectare and stand basal area. Moreover, the model includes a stand volume equation as an output function to estimate this variable at any point in time. Transition functions were fitted separately and simultaneously. Moreover, a continuous autoregressive error structure is also included in the modelling process. For fitting volume equation, generalized method of moments was used to get efficient parameter estimates under heteroscedastic conditions.
Conclusions： A simple model containing few free parameters performed well and is particularly well suited to situations where available data is scarce.     

基于省域的中国甜瓜生产比较优势空间特征分析

[目的]分析中国甜瓜生产比较优势区域的空间特征,为中国甜瓜产业战略决策提供参考.[方法]以基于省域的中国甜瓜播种面积、总产量和单位面积产量为研究单元,系统分析中国甜瓜产量、效率、规模、集中度、综合比较优势、单位面积产量比、播种面积比及其空间分布特征.利用中国的农业统计资料,以产量比较优势指数、效率比较优势指数、规模比较优势指数、集中度比较优势指数、综合比较优势指数、单位面积产量比指数及播种面积比指数分析中国甜瓜生产比较优势状况,并通过“地图汇”软件在地图上进行空间表达.[结果]中国甜瓜生产优势区域依次为新疆、黑龙江、吉林、山东、河南、内蒙古、辽宁、江苏、湖北、湖南和上海等11个省（市、区）.东北和华中地区为中国甜瓜生产的综合比较优势区,华东、华北、西北和华南地区可作为后备发展区域,西南地区近年来在瓜类生产中优先发展甜瓜产业,其优势不断增强.[结论]中国各地区甜瓜生产仍需加强发挥规模效应和集聚效应,同时要进一步优化中国甜瓜产业的区域优势布局,充分协调甜瓜生产,使其达到区域间和季节性平衡,提高甜瓜专业化生产水平,推动区域间有序健康竞争.     

绿色农药市场发展空间广阔

受益于国内外刚性需求增长、产业结构调整、环保政策趋严、库存消化完全等利好因素,2013年农药行业效益实现较大提升,形势好于历史最好年份2008年。业内人士普遍认为,农药市场高景气度有望持续,在发展生态农业、环保门槛提升的大背景下,绿色农药契合国家政策需要及产业发展,发展良机凸显,市场空间广阔。     

唐宁军：在城市旧梦里构筑人生梦想空间

唐宁军,70后,人称“老唐”,兼具儒雅、有学识、文艺范儿和梦想主义等特质。他在南京城南老区间可利用资源极其有限的情况下,收集6万多斤老木料和1万多块老墙砖,历时五个多月的时间,将一家800多平方米的旧旅馆,加以精心装修和创意设计,改造成了一处被他取名为“青果”的地方。