我国森林蔬菜的开发利用现状与前景

对我国森林蔬菜开发利用的意义、现状和存在的问题进行了综述,并结合存在的问题提出了具有可行性的建议和对策,以期为森林蔬菜开发利用研究提供一些理论性的依据,使我国森林蔬菜产业早日走上规模化、国际化道路.     

Differential responses of Bolivian timber species to prescribed fire and other gap treatments

We followed the establishment and growth response of 13 commercial tree species to canopy opening, above-ground biomass removal, and experimental burns of low and high intensities in a lowland dry forest in Bolivia. Three patterns of response to treatments were observed among the most abundant commercial tree species. (1) Shade-intolerant species regenerated mostly from seed and had the highest survival and growth rates following high-intensity burns. (2) Shade-tolerant species were abundant in gap control and plant removal treatments. Treatments had little effect on the height growth of these species. (3) Individuals of root sprouting species were most abundant following plant removal and low-intensity burn treatments. Treatments had little effect on the height growth of these species. The wide variation in species responses to gap treatments found in this study not only reinforces the concept that species are distributed along a continuum of shade-tolerance levels, but that other aspects of species biology, such as seed dispersal type or sprouting behavior, further differentiate regeneration strategies. The variety of regeneration strategies found among the species at this forest site will require a flexible management scheme that mixes more intensive silvicultural treatments such as prescribed burning with less intensive treatments.     

河北省林木种苗发展现状、趋势与管理对策

总结了河北省林木种苗建设取得的成绩及存在的问题，根据林业和生态建设的新形势及河北省种苗发展现状，分析了林木种苗发展的趋势，提出了河北省林木种苗管理的总体思路和“坚持一个中心，抓好两件大事，建设三大体系，抓好四项工作”的管理对策。     

彩叶植物的观赏价值及应用前景探讨

文章在阐述彩叶植物具有极高观赏价值的基础上，概括了彩叶植物在园林中的应用形式，并指出彩叶植物具有广阔的市场发展前景。     

浅谈非公有制林业的发展障碍与对策

阐述了非公有制林业的内涵和外延，以及法律地位。通过对四川省非公有制林业发展现状、发展障碍的分析，提出加快发展非公有制林业的建议与对策。     

我国人造板工业发展趋势预测与原料创新研究

围绕我国木材资源短缺和人造板工业高速发展的现状，阐述我国人造板原材料演变的历程。农作物秸秆作为绿色原料，在河南、山东、江苏、黑龙江等省份储量丰富。本文从工艺、成本、环保等角度，分析其作为人造板原料所具有的优势，并讨论了21世纪中国秸秆人造板工业的发展前景。     

Tree-ring: a suitable implement for spatial and temporal fire distribution analysis in savanna woodland and dry forest

Based on 120 stem discs collected during3 months of fieldwork along a 12 km route,the history of fires in the Wari Maro Forest(09 1000 N–02 1000E) over the past century in savanna woodland and dry forest was reconstituted.Three major ecological areas are characterized:one highly burnt zone located between two relative less burnt areas.By analyzing tree rings,246 fire scars were identified.The scars were caused by 51 fire years,occurring at a mean interval of 2.23 years.From 1890 to1965,only 6 years with fires were recorded from sampled trees.Since 1966,no year has passed without fire.The fire frequency point scale reached 14 years.This was the case of Burkea africana,which has been identified as a species tolerant to fire and could be planted to create a natural firewall.In contrast,Anogeissus leiocarpa is highly sensitive to fire,and in a dry forest ecosystem that burns seasonally,it requires a special conservation plan.Two new concepts are described:the rebarking of trees after fire and Mean Kilometer Fire Interval.The first concept was tested with Daniellia oliveri(Rolfe) Hutch & Dalz trees,and the second concept was used to evaluate spatial fire distribution.We demonstrate that savanna woodland and dry forest were subject to a degradation process caused by destructive fires related to vegetation cover clearance and illegal logging.     

The face of conservation responding to a dynamically changing world

In its 40‐year history, the science of conservation has faced unprecedented challenges in terms of environmental damage and rapid global change, and environmental problems are only increasing as greater demands are placed on limited natural resources. Conservation science has been adapting to keep pace with these changes. Here, we highlight contemporary and emerging trends and innovations in conservation science that we believe represent the most effective responses to biodiversity threats. We focus on specific areas where conservation science has had to adjust its approach to address emerging threats to biodiversity, including habitat destruction and degradation, climate change, declining populations and invasive species. We also document changes in attitudes, norms and practices among conservation scientists. A key component to success is engaging and maintaining public support for conservation, which can be facilitated through the use of technology. These recent trends in conservation and management are innovative and will assist in optimizing conservation strategies, increasing our leverage with the general public and tackling our current environmental challenges.     

发育大豆子叶细胞中酸性磷酸酶的亚细胞学定位

本实验采用电镜细胞化学技术，观察了酸性磷酸酶在发育中大豆子叶细胞内的亚细胞学分布。酸性磷酸酶除分布在细胞核内的部分染色质上，内质网膜上，质体胞质小泡和胞质中，主要积累于蛋白体内。     

TOWARD SUSTAINABLE MAIZE PRODUCTION FOR SMALLHOLDERS THROUGH OPTIMIZED STRATEGIES IN NORTH CHINA

● County-level sustainability assessment of maize production is presented. ● County-level improvement potential exhibits a large spatial heterogeneity. ● Promoting technical innovations can facilitate China’s agricultural transition. Agricultural production by smallholders is crucial for ensuring food provision in China. However, smallholders face a series of challenges on their farms including high-to-excess resource inputs, low use efficiency, as well as negative environmental impacts, which may be unfavorable for sustainable agriculture production. This study developed a county-level sustainability assessment of maize production in Hebei, China, by applying multiple data sources in combination with emergy, carbon footprint, nitrogen footprint and cost-benefit analyses. Scenario analysis was applied to explore the localized implementation strategies to achieve the sustainable farming system. The results show that the average emergy sustainability index (ESI) of maize at 2.31 is relatively low. The average greenhouse gas (GHG) emissions and reactive nitrogen (Nr) losses are 0.15 g·kcal⁻¹ CO₂-eq and 3.75 mg·kcal⁻¹ N, respectively. The average cost and net income are 12,700 and 4340 CNY·ha⁻¹, respectively. These results indicate a great potential to improve the environmental-economic sustainability of the maize production system of smallholders. In addition, the environmental and economic indicators calculated from the maize production show a substantial spatial heterogeneity among counties, indicating a requirement for different optimization strategies to improve the environment-economy sustainability at a finer scale. Based on the multiple scenario analysis, optimal strategies targeting each county are proposed. By adopting the optimal strategies, the average ESI and net income could increase by 32% and 83%, respectively, and the average GHG emissions and Nr losses reduce by 33% and 35%, respectively. These findings provide an important reference for adopting different strategies to achieve environment-economy sustainability for smallholders production systems with diverse landscapes in North China and propose a transition pathway toward achieving agriculture sustainability for smallholders worldwide.