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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.10.011 Byline: Hikaru Komatsu (a), Tomonori Kume (b), Kyoichi Otsuki (a) Abstract: Researchers and journalists in Japan recently proposed forest management as an alternative to dam reservoir development for water resource management. To examine the validity of the proposal, we compared the potential low-flow increase due to forest clearcutting with the increase due to dam reservoir development. Here, we focused on forest clearcutting as an end member among various types of forest management. We first analyzed runoff data for five catchments and found a positive correlation between annual precipitation and the low-flow increase due to deforestation. We then examined the increase in low-flow rates due to dam reservoir development (dQ.sub.d) using inflow and outflow data for 45 dam reservoirs across Japan. Using the relationship between annual precipitation and the low-flow increase due to deforestation, we estimated the potential increase in the low-flow rate for each dam reservoir watershed if forests in the watershed were clearcut (dQ.sub.f). Only 6 of the 45 samples satisfied dQ.sub.f dQ.sub.d , indicating that the potential increase in the low-flow rate due to forest clearcutting was less than the increase due to dam reservoir development in most cases. Twenty-five of the 45 samples satisfied dQ.sub.f Author Affiliation: (a) Kasuya Research Forest, Kyushu University, 394 Tsubakuro, Sasaguri, Kasuya, Fukuoka 811-2415, Japan (b) School of Forestry and Resource Conservation, National Taiwan University, 1 , Roosevelt Road, Taipei 106, Taiwan Article History: Received 1 April 2009; Revised 8 October 2009; Accepted 23 October 2009

Degrowth, i.e., a planned reduction in environmental impacts and economic scale, is increasingly discussed as a viable option for achieving sustainability. Yet, opponents counter that degrowth entails declines in economic standards, which will, in turn, reduce individual happiness and collective wellbeing. Our study explores the existing theoretical debate empirically, examining the case of Japan. There long-term decline in economic standards has not led to long-term decline in subjective wellbeing, thus bolstering the case for degrowth. • Degrowth is an effective option for achieving sustainability. • Opponents counter that degrowth will reduce collective wellbeing. • Our study explores this existing debate empirically, examining the case of Japan. • Decline in economic standards did not lead to decline in subjective wellbeing. • Political and popular feasibility of degrowth might be higher than expected. [ABSTRACT FROM AUTHOR]

Previous studies have revealed that changes in forest structure due to management (e.g., thinning, aging, and clearcutting) could affect the forest water balance. However, there are unexplained variability in changes in the annual water balance with changing structure among different sites. This is the case even when analyzing data for specific species/regions. For a more advanced and process-based understanding of changes in the water balance with changing forest structure, we examined transpiration ( E ) observed using the sap-flux method for 14 Japanese cedar and cypress plantations with various structure (e.g., stem density and diameter) in Japan and surrounding areas and developed a model relating E with structural parameters. We expressed E using the simplified Penman–Monteith equation and modeled canopy conductance ( G c ) as a product of reference G c ( G cref ) when vapor pressure deficit is 1.0 kPa and functions expressing the responses of G c to meteorological factors. We determined G cref and parameters of the functions for the sites separately. E observed for the 14 sites was not reproduced well by the model when using mean values of G cref and the parameters among the sites. However, E observed for the sites was reproduced well when using G cref determined for each site and mean values of the parameters of the functions among the sites, similar to the case when using G cref and the parameters of the functions determined for each site. These results suggest that considering variations in G cref among the sites was important to reproduce variations in E , but considering variations in the parameters of the functions was not. Our analysis revealed that G cref linearly related with the sapwood area on a stand scale ( A ) and that A linearly related with stem density ( N ) and powers of the mean stem diameter ( d m ). Thus, we proposed a model relating E with A (or N and d m ), where G cref was calculated from A (or N and d m ) and the parameters of the functions were assumed to be the mean values among the sites. This model estimates changes in E with changing structure from commonly available data ( N and d m ), and therefore helps improve our understanding of the underlying processes of the changes in the water balance for Japanese cedar and cypress plantations. [ABSTRACT FROM AUTHOR]

Abstract: In western Japan, Moso bamboo (Phyllostachys pubescens) forests have been expanding by replacing surrounding vegetation such as coniferous plantation forests and natural broadleaved forests. It has been speculated that the replacement of surrounding vegetation by bamboo forests could alter the vegetation water cycle and available water resources. We quantified stand-scale transpiration (E) in a bamboo forest on the basis of sap-flux measurements and compared the E value with values for coniferous forests. The annual E was estimated to be 567mm. Seasonal trends in E primarily corresponded to seasonal trends in the vapor pressure deficit. Annual E for the bamboo forest was higher than that for the coniferous forests by 12% of annual precipitation (P). This difference in annual E is comparable with the difference in annual interception evaporation (I) relative to P between bamboo and coniferous forests; previous studies reported lower I for bamboo forests by ∼10% of P. Thus, the sum of E and I was comparable for bamboo and coniferous forests. As this study is the first measuring E of bamboo forests, further studies are required to examine the generality of our results. [Copyright &y& Elsevier]

Abstract: The applicability of sap flux (F d ) measurements to bamboo forests has not been studied. This study was undertaken to establish an optimal and effective design for stand-scale transpiration (E) estimates in a Moso bamboo forest. To this aim, we validated F d measurements in Moso bamboos in a cut bamboo experiment. In addition, we analyzed how sample sizes affect the reliability of E estimates calculated from F d and conducting culm area (A S_b ). In the cut bamboo experiments, we found that F d measurement using a 10mm probe was a valid means of determining the water-use behavior of a Moso bamboo, although a specific correction was needed. Furthermore, we calculated E from stand A S_b (A S_stand) and mean stand F d (J S ). Employing Monte Carlo analysis, we examined potential errors associated with sample size in E, A S_stand, and J S using an original dataset with A S_b and F d measured for 40 and 16 individuals, respectively. Consequently, we determined the optimal sample size for both A S_stand and J S estimates as 11. The optimal sample sizes for J S were almost the same under different vapor pressure deficit and soil moisture conditions. The optimal sample size for J S at the study site was less than that of a coniferous plantation in the same region probably owing to small individual-to-individual variations in sap flux in the Moso bamboo forest. Our study concludes that sap flux measurements are an applicable technique for assessing water use in Moso bamboo forests. [ABSTRACT FROM AUTHOR]

Abstract: Several previous studies in Japan have examined differences in rainfall interception amounts induced by differences in forest properties by comparing the annual rainfall interception ratios (annual rainfall interception divided by annual rainfall) from various sites without considering variations in meteorological conditions between sites. Rainfall interception actually depends on meteorological conditions as well as forest properties. This study examined variations in the annual interception ratio relating to the variation in annual rainfall, which would be the primary factor relating to the interception ratio, across Japan with the use of a rainfall interception model assuming the same forest properties (i.e., the canopy storage capacity, canopy closure, leaf area index (LAI), and the bulk coefficient for sensible heat transfer). The ratio ranged between 0.12 and 0.24 across Japan and was highly correlated to annual rainfall. This indicates that considering the variation in annual rainfall is critical for assessing the difference in rainfall interception amounts induced by forest properties. We reconsidered the results of previous studies in Japan that compared annual interception ratios between sites with different forest properties: (i) there is no clear difference in interception amounts between broadleaf and coniferous forests and (ii) there is a positive correlation in stem density and interception amounts for coniferous forests. These results still held when considering differences in annual rainfall between sites. [Copyright &y& Elsevier]

Abstract: This study examined the change of water yield when a broad-leaved forest is converted to a coniferous plantation forest after clear-cutting in northern Japan where monthly precipitation is evenly distributed. Annual water yield after clear-cut was greater than observed in a broad-leaved forest and then decreased with the growth of a coniferous plantation forest. This reduction ceased after 30 years from the planting of coniferous seedlings. Water yield of a coniferous forest at this stage was smaller than observed in a broad-leaved forest. Results from monthly water yield examinations suggested that the difference in annual water yield was primarily caused by the difference in winter interception loss between broad-leaved deciduous and coniferous evergreen forests. The above results suggest that converting coniferous forests into broad-leaved forests can be used to increase water yield in these regions. [Copyright &y& Elsevier]

Abstract: Tropical seasonal forests play an important role in global cycling of carbon, water and energy in terms of inter-annual variation in the growing season. We investigated year-to-year variations in the canopy duration and transpiration period as measures of growing season length using time series data of radiative transmittance and sap flux in a teak plantation in Thailand over a 3-year period. In 2001, leaf-out and tree transpiration commenced earlier than in 2002 and 2003 following exceptionally heavy rainfall in the late dry season, strongly suggesting that enhanced soil moisture advanced the timing of leaf unfolding and commencement of tree transpiration. The commencement of leaf-fall and decline in tree transpiration at the beginning of 2003 were late in coming in correlation with a prolonged rainy season. Declines in tree transpiration were directly controlled by soil moisture conditions at the beginning of the dry season, with time lags between the timing of leaf-fall and decline in tree transpiration. These results revealed that soil moisture conditions are a major determinant of large inter-annual variation in the growing season at this site. The variation in canopy duration and transpiration period in this study, from 2001 to 2004, spanned about 40 and 60 days, respectively. This was much larger than the inter-annual variations previously reported in temperate deciduous forests, implying a profound potential impact on surface energy balance and canopy-atmosphere water and carbon exchange on an annual time scale. [Copyright &y& Elsevier]

• We developed a model tool to assist forest and water-resource policymaking. • The model focuses on two major plantation species in Japan. • The model can compare available water resources for different management scenarios. • The model can assess effectiveness of existing policy recommendations. • The study inspires development of similar models for other species/regions. Examining changes in evapotranspiration with forest management is one starting point for comprehensively understanding the impacts of forest management on water resources and forest resilience. This study builds on our previous work and develops a practical model that predicts changes in evapotranspiration with the management of Japanese cedar and cypress plantations. The model has distinct features that it requires only stem density, mean diameter at breast height, and basic meteorological data as inputs. This study first confirms that the model predicts annual evapotranspiration for cedar and cypress with relatively small errors (approximately 60 mm at the maximum). Next, this study shows that the model predicts changes in annual evapotranspiration with thinning and clearcutting of cedar and cypress with small errors (the mean absolute error of 86 mm). This study then demonstrates that coupling the model and yield tables enables prediction of annual evapotranspiration for different management scenarios and then the assessment of policy recommendations. Indeed, our model prediction suggests that the decrease in annual evapotranspiration with cedar and cypress aging is seemingly much smaller than that assumed in existing policy recommendations. Our model also suggests that the decrease in annual evapotranspiration with aging can more than triple by thinning at a rate of 50%, although this suggestion should be tested by future observation studies. The model is applicable only to Japanese cedar and cypress plantations under Japan's meteorological conditions, but similar models for other mono-specific plantations can be developed. This study will thus inspire forest scientists to develop models that assist policymaking for other species in other areas. [ABSTRACT FROM AUTHOR]

The overarching assumption of SDG 4, that progress towards 'quality education' will lead to greater sustainability, is not rooted in evidence but instead in ideology. From the outset, a wider set of sustainability indicators (such as ecological footprint) were excluded, and even today, after a decade of work, there exists no indicator to capture 'sustainability'. Instead SDG 4 discussions remain a mixed bag of routine monitoring of outcomes, advocacy for more funding, and banal policy recommendations. The development 'specialists' leading all of this have turned a blind eye to this obvious fact, and shown strikingly little willingness to think differently – a position that is intellectually irresponsible, politically unaccountable, and deeply unethical in the context of an accelerating climate crisis. The next 7 years should be refocused on highlighting alternatives and developing evidence for the post-2030 agenda. • No evidence exists showing SDG 4 leads to sustainability. • SDG 4 implementation further extends the unsustainable 'modern paradigm'. • A growing body of research highlights potential alternatives. • SDG 4 debates should be (re)focused on generating evidence for the post-2030 agenda. [ABSTRACT FROM AUTHOR]

Boreal forests play an important role in the global balance of energy and CO2. Our previous study of elaborate eddy covariance observations in a Siberian boreal larch forest, conducted both above the forest canopy and at the forest floor, revealed a significant contribution of latent heat flux (LE) from the cowberry understory to the whole ecosystem LE. Thus, in the present study, we examined what factors control the partitioning of whole ecosystem LE and CO2 flux into the understory and overstory vegetation, using detailed leaf-level physiology (for both understory and overstory vegetation) and soil respiration property measurements as well as a multilayer soil-vegetation-atmosphere transfer (SVAT) model. The modeling results showed that the larch overstory's leaf area index (LAI) and vertical profile of leaf photosynthetic capacity were major factors determining the flux partitioning in this boreal forest ecosystem. This is unlike other forest ecosystems that tend to have dense LAI. We concluded that control of the larch overstory's LAI had a relationship with both the coexistence of the larch with the cowberry understory and with the water resources available to the total forest ecosystem. [Copyright &y& Elsevier]