scholarly journals Criterion for the Need to Weed on Sugi (Cryptomeria japonica) Plantations Varies according to Competing Vegetation Types

2020 ◽  
Vol 102 (4) ◽  
pp. 225-231
Author(s):  
Yuki Tsurusaki ◽  
Hiromi Yamagawa ◽  
Satoshi Ito ◽  
Hidetoshi Shigenaga ◽  
Shigeyuki Sasaki
2020 ◽  
Vol 45 (3) ◽  
pp. 537-543
Author(s):  
Karinne Sampaio Valdemarin ◽  
Jair Eustáquio Quintino Faria ◽  
Fiorella Fernanda Mazine ◽  
Vinicius Castro Souza

Abstract—A new species of Eugenia from the Atlantic forest of Brazil is described and illustrated. Eugenia flavicarpa is restricted to the Floresta de Tabuleiro (lowland forests) of Espírito Santo state and is nested in Eugenia subg. Pseudeugenia. Considering all other species of the subgenus that occur in forest vegetation types of the Atlantic forest phytogeographic domain, Eugenia flavicarpa can be distinguished mainly by the combination of smooth leaves with indumentum on both surfaces, with two marginal veins, usually ramiflorous inflorescences, pedicels 4.5‐9.7 mm long, flower buds 3.5‐4 mm in diameter, and by the calyx lobes that are 2‐3 mm long with rounded to obtuse apices. Morphological analyses were performed to explore the significance of quantitative diagnostic features between the new species and the closely related species, Eugenia farneyi. Notes on the habitat, distribution, phenology, and conservation status of Eugenia flavicarpa are provided, as well as a key for all species of Eugenia subg. Pseudeugenia from forest vegetation of the Atlantic forest phytogeographic domain.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jie Chen ◽  
Xue-wen Lei ◽  
Han-lin Zhang ◽  
Zhi Lin ◽  
Hui Wang ◽  
...  

AbstractThe problems caused by the interaction between slopes and hydrologic environment in traffic civil engineering are very serious in the granite residual soil area of China, especially in Guangdong Province. Against the background of two heavy rainfall events occurring during a short period due to a typhoon making landfall twice or even two typhoons consecutively making landfall, laboratory model tests were carried out on the hydrological effects of the granite residual soil slope considering three vegetation types under artificial rainfall. The variation in slope surface runoff, soil moisture content and rain seepage over time was recorded during the tests. The results indicate that surface vegetation first effectively reduces the splash erosion impact of rainwater on slopes and then influences the slope hydrological effect through rainwater forms adjustment. (1) The exposed slope has weak resistance to two consecutive heavy rains, the degree of slope scouring and soil erosion damage will increase greatly during the second rainfall. (2) The multiple hindrances of the stem leaf of Zoysia japonica plays a leading role in regulating the hydrological effect of slope, the root system has little effect on the permeability and water storage capacity of slope soil, but improves the erosion resistance of it. (3) Both the stem leaf and root system of Nephrolepis cordifolia have important roles on the hydrological effect. The stem leaf can stabilize the infiltration of rainwater, and successfully inhibit the surface runoff under continuous secondary heavy rainfall. The root system significantly enhances the water storage capacity of the slope, and greatly increases the permeability of the slope soil in the second rainfall, which is totally different from that of the exposed and Zoysia japonica slopes. (4) Zoysia is a suitable vegetation species in terms of slope protection because of its comprehensive slope protection effect. Nephrolepis cordifolia should be cautiously planted as slope protection vegetation. Only on slopes with no stability issues should Nephrolepis cordifolia be considered to preserve soil and water.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 352
Author(s):  
Joshua L. Sloan ◽  
Francis K. Salifu ◽  
Douglass F. Jacobs

Intensively managed forest plantations often require fertilization to maintain site fertility and to improve growth and yield over successive rotations. We applied urea-based “enhanced-efficiency fertilizers” (EEF) containing 0.5 atom% 15N at a rate of 224 kg N ha−1 to soils under mid-rotation black walnut (Juglans nigra L.) plantations to track the fate of applied 15N within aboveground ecosystem components during the 12-month period after application. Treatments included Agrotain Ultra (urea coated with a urease inhibitor), Arborite EC (urea coated with water-soluble boron and phosphate), Agrium ESN (polymer-coated urea), uncoated urea, and an unfertilized control. Agrotain Ultra and Arborite EC increased N concentrations of competing vegetation within one month after fertilization, while neither Agrium ESN nor uncoated urea had any effect on competing vegetation N concentrations during the experiment. Agrotain Ultra and Arborite EC increased δ15N values in leaves of crop trees above those of controls at one and two months after fertilization, respectively. By contrast, Agrium ESN and uncoated urea had no effect on δ15N values in leaves of crop trees until three months after fertilization. Fertilizer N recovery (FNR) varied among ecosystem components, with competing vegetation acting as a sink for applied nutrients. There were no significant differences in FNR for all the urea-based EEF products compared to uncoated urea. Agrium ESN was the only EEF that exhibited controlled-release activity in this study, with other fertilizers behaving similarly to uncoated urea.


2020 ◽  
Vol 13 (1) ◽  
pp. 41
Author(s):  
Iván Barbero-Bermejo ◽  
Gabriela Crespo-Luengo ◽  
Ricardo Enrique Hernández-Lambraño ◽  
David Rodríguez de la Cruz ◽  
José Ángel Sánchez-Agudo

The design of conservation plans for the improvement of habitats of threatened species constitutes one of the most plausible possibilities of intervention in the structure and composition of the landscape of a large territory. In this work we focus on the Iberian lynx in order to establish potential ecological corridors using ecoinformatic tools from the GIS environment to improve connectivity between the existing natural spaces within the scope of its historical distribution. We processed 669 records of the presence of the lynx and six predictor variables linked to the habitat of the species. With this, corridors have been generated between natural areas. The determination of possible bottlenecks or dangerous areas (e.g., hitches on highways) allows for focusing efforts on their conservation. This type of approach seeks to improve efficiency in the design of measures aimed at expanding the territory’s capacity to host its populations, improving both its viability and that of all the other species that are linked to it. The proposals for action on the specific areas defined by the models elaborated in this work would imply interventions on the land uses and existing vegetation types in order to improve connectivity throughout the territory and increase the resilience of its ecosystems.


Sign in / Sign up

Export Citation Format

Share Document