Effect of strip thinning on rainfall interception in a Japanese cypress plantation

Interception is an important hydrological process relating to canopy gas exchange and takes a significant part from precipitation. The real interception process by the needle leaves is worth discussing because their shape may allow interception by both surfaces and thus affects photosynthesis by blocking stomata. Therefore, the aim of this study is to figure out the distribution of interception at needle leaf and its relation with the gas exchange of wet canopy.We measured ecosystem flux and wetness from a Japanese cypress forest by the advanced water-proof enclosed gas analyzer (LI7200, LI-COR, the USA) and handmade wetness sensors. A SVAT (soil-vegetation-atmosphere transfer) multilayer model with two rainfall interception solutions (free gas exchange with interception only by the adaxial surface and no gas exchange with interception by both surfaces) has been used to figure out the distribution of rainfall interception, snow melting water distribution and photosynthesis process of wet canopy.The results include precipitation events from 4 years, showing that interception can happen not only on the adaxial surface but also on both surfaces. Meanwhile, when the intensity of rainfall events enhanced, the possibility of interception on both surfaces increased. Hence, such kind of needle leaf can process photosynthesis during the rainfall. Future studies should concentrate on improving the model for snow process and soil respiration. More comparison with other types of forests may also provide worthy results for learning how plants adjust photosynthesis to adapt the climate change.

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Loading rates of nutrients discharging from a golf course and a neighboring forested basin

Water Science & Technology ◽

10.2166/wst.1999.0535 ◽

1999 ◽

Vol 39 (12) ◽

pp. 99-107 ◽

Cited By ~ 10

Author(s):

Takao Kunimatsu ◽

Miki Sudo ◽

Takeshi Kawachi

Keyword(s):

Nutrient Loading ◽

Chamaecyparis Obtusa ◽

Phosphorus Loading ◽

Golf Course ◽

Nutrient Concentrations ◽

Golf Courses ◽

Japanese Cypress ◽

Arithmetic Average ◽

Loading Rates ◽

Runoff Rate

In the last ten years, the number of golf courses has been increasing in some countries as the game gains popularity. This indicates, a need to estimate the nutrient loading from golf courses in order to prevent the eutrophication of water bodies. Nutrient concentrations and flow rates of a brook were measured once a week from 1989 to 1990 at two sites: Site A of a brook flowing out from D-golf course (53 ha) and Site B of the same brook discharging into the golf course from an upper forested basin (23 ha) covered mainly with planted Japanese cypress (Chamaecyparis obtusa SIEB. et ZUCC). The bedrock of the area was granite. The annual values of precipitation and mean temperature were 1947 mm and 13.5°C in 1989, respectively. The arithmetic average values of discharge from the forested basin and the golf course were 0.392 and 1.26 mg/l total nitrogen (TN), 0.0072 and 0.145 mg/l total phosphorus (TP), 0.82 and 3.53 mg/l potassium ion (K+, 5.92 and 8.24 mg/l sodium ion (Na+), 2.1 and 9.9 mg/l suspending solid (0.001–2.0 mm, SS), 0.087 and 0.147 mS/cm electric conductivity (EC), and 0.031 and 0.037 m3/km2•s specific discharge, respectively. The loading rates of the forested basin and the golf course were 5.42 and 13.5 TN, 0.133 and 3.04 TP, 8.84 and 33.9 K+, 55.0 and 73.0 Na+, and 54.3 and 118 SS in kg/ha•y. The leaching and runoff rate of nitrogen in the chemical fertilizers applied on the golf course was calculated as 32%. These results indicated the importance of controlling the phosphorus loading for the management of golf courses.

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A comparison of the baseflow recession constant (K) between a Japanese cypress and mixed-broadleaf forest via six estimation methods

Sustainable Water Resources Management ◽

10.1007/s40899-020-00481-w ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Anand Nainar ◽

Nobuaki Tanaka ◽

Takanori Sato ◽

Koju Kishimoto ◽

Koichiro Kuraji

Keyword(s):

Estimation Methods ◽

Japanese Cypress ◽

Broadleaf Forest ◽

Recession Constant

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Heat transfer, physiological responses, and subjective perceptions during short contact time with wood or other materials

Journal of Wood Science ◽

10.1186/s10086-021-01960-0 ◽

2021 ◽

Vol 67 (1) ◽

Author(s):

Yuko Tsunetsugu ◽

Masaki Sugiyama

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Blood Pressure ◽

Physiological Stress ◽

Physiological Responses ◽

Chamaecyparis Obtusa ◽

Material Interface ◽

Japanese Cypress ◽

Subjective Perceptions ◽

Short Contact Time

AbstractThis study investigates the physiological responses and subjective perceptions of touching wood. In particular, it focuses on their respective relationships with the amount of heat transfer across the hand–material interface during contact. The study participants included 55 university students (20 females and 35 males) who gave written informed consent. The participants’ blood pressure, pulse rate, and cerebral blood hemoglobin concentrations were measured continuously for 90 s while they gently held vertical bar-shaped specimens of Japanese cypress (Chamaecyparis obtusa), Japanese oak (Quercus crispula), polyethylene, and aluminum. The specimens also included wood with a surface coating. We measured subjective warmth and comfort as well as the heat flux between the palm and the surface of the material. The wooden materials were rated as significantly warmer compared to aluminum and polyethylene, regardless of the wood species (cypress or oak) or its coating; this result corresponds with smaller heat transfers in the wooden materials. Additionally, the wooden materials were more comfortable to hold as compared to the aluminum bar. Based on the changes in blood pressure, touching Japanese cypress and uncoated Japanese oak were interpreted to induce less physiological stress. Therefore, we can conclude that wood, with lower thermal conductivity, feels warm, and it causes relatively smaller physiological changes compared to other materials with higher thermal conductivity. Thus, they may present less physiological burdens when touched.

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