Agroclimatological problems in the Taklimakan Desert and its surrounding area in NW China were discussed with reference to the results of our previous studies carried on since the early 1990s, together with literature published in China. Farmers at the oases have been suffering from occasional heavy rainfall, causing floods and damaging construction works. It is worthy to note that human ecosystems in arid areas are more vulnerable to extremely wet conditions, which occur infrequently, than to dry conditions.
Agroclimatologically, strong sand-dust storms, called “Kara Bran (Black Wind),” also play a seriously negative role in the Taklimakan Desert. Cotton, which is cultivated as a main cash crop for the farmers, has frequently been damaged severely. The amount of water used for irrigation per family is decreasing because of population growth. Limits on the ratio of irrigated land to total cultivated land differ between the northern fringe and the southern fringe of the Tarim Basin. The tributary size (population) is also important in determining the limits. The crop calendar is decided by the amount of water available. The income of farmers' families is very low, because of low production under the severe environmental conditions for cultivation, which are common at desert oases. Raising the income of the farmers is one way to decrease or alleviate desertification, because they wouldn't have to go to the desert to collect firewood. The farmers who are living under the severe economic conditions cannot buy coal because of the price. The farmer's recognition of an increasing trend in the frequency of very strong winds, Kara Bran, is quite accurate, according to the interview survey. The results coincide with the records at the local meteorological observatories.

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The effect of environmental variability is one of the major concerns in experimental design for both research in plant systems and greenhouse plant production. Microclimates surrounding plants are not usually uniform. Therefore, many samples and sensors are required to obtain a true representation of the plant population. A plant monitoring system capable of reducing the required number of samples by reducing environmental variability would be more advantageous. To better understand plant-environment interaction, it is essential to study plants, microclimate surrounding the plants and the growth media. To achieve this, the monitoring system must be equipped with proper instrumentation.
To achieve proper management practices and sustainable greenhouse production, it is essential first to understand plants and their interactions with their surroundings and then establish plant response-based sensing and control strategies for greenhouse processes. Therefore, an effort was conducted to review and discuss current sensing and control strategies in greenhouse research and plant production and provide recommendations on plant response-based sensing and control strategies for sustainable greenhouse production.

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近年，開発途上国でも機械耕耘が広がってきた。これでできる耕盤が根の貫入を減らして吸水を抑制すること，耕盤下への水移動を抑制することはよく知られている。しかし，作物の栽培生理に関する耕盤の影響の研究は十分でない。そこで，農業生産に及ぼす耕盤の影響を軽減するために，石垣島にある国際農林水産業研究センター（JIRCAS）沖縄支所で耕盤がサトウキビの蒸散，生育，収量に及ぼす影響を解析した。
露地圃場を耕盤破砕区と耕盤無破砕区に分け，2000年12月にサトウキビの2節茎を植え付け，植被が発達しきった2001年9月に蒸散を茎流センサーで測定した。破砕区の蒸散は気象的なポテンシャルにほぼ等しかったが，無破砕区の蒸散はその半分であった。測定期間中の9月の降水量は多く，耕盤より上に多くの根を発達させた無破砕区では根圏土壌水分は早急に回復したにもかかわらず，9月を通じて蒸散は増加しなかった。この結果は，無破砕区での蒸散抑制の原因は土壌水分の不足だけでないことを示す。無破砕区の葉面積に対する蒸散の割合が極めて低かったこと，無破砕区で体内水分が増加したことから，この原因は不可逆的な気孔コンダクタンスの過度な低下にあるといえた。一般にこのような気孔コンダクタンスの低下は光合成の低下を伴うため，生育，収量を抑制する。これを裏付けるように収量は耕盤を破砕することにより高まった。このことは気孔コンダクタンスの低下を防ぐ耕種的な対策が収量改善に有効なことを示唆する。また，収量は処理区にかかわらず茎数の増加で多くなった。このことは，有効茎が形成される時期に当たる雨期の排水と通気性が耕盤破砕区で高まり収量が改善されたことも考えられる。

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We predict current distribution and abundance for tree species present in eastern North America, and subsequently estimate potential suitable habitat for those species under a changed climate with 2×CO₂. We used a series of statistical models (i. e., Regression Tree Analysis (RTA), Multivariate Adaptive Regression Splines (MARS), Bagging Trees (BT) and Random Forests (RF)) via our model, DISTRIB, for this purpose. These techniques were evaluated on several tree species, and advantages and disadvantages of each method were noted. RF provides the best prediction maps of potential suitable habitat. Overall, a combination of RTA, BT, and RF may yield the best information and most interpretable maps of suitable habitat. Using these tools, we provide statistics on potential changes in suitable habitat for 135 tree species of eastern North America.
A suitable habitat does not guarantee the presence of a species, as many barriers for the species still exist before it will be able to colonize that new suitable habitat. Dispersal ability, abundance of the colonizing species, and the nature of fragmented landscapes also influence migration and are modeled with our cellular automata model, SHIFT. For each cell outside a species' current boundary, SHIFT creates an estimate of the probability that each unoccupied cell will become colonized over 100 years. By evaluating the probability of colonization within the potential “new” suitable habitat, we can estimate the proportion of new habitat that might be colonized within a century. This proportion is low (<15%) for five example species, suggesting that there is a serious lag between the potential movement of suitable habitat and the potential for the species to migrate into the new habitat. However, humans could accidentally or purposefully alter the migration rates of species by physically moving the propagules.

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In this study, in order to measure the three-dimensional structure of forest, a new technique using a laser scanner was developed in a five-year-old Japanese larch community with a tree height of about 5 m grown at the experimental field of the National Institute for Environmental Studies. The Japanese larch community was divided into cubic cells, and plant area density (PAD) was calculated for each cubic cell from the gap fraction, which is the probability that a laser beam passes through a cubic cell. Leaf area density (LAD) was estimated from the difference between PAD measured in November 2003 and wood area density (WAD) measured in March 2004. Average plant inclination angle (APIA) and average leaf inclination angle (ALIA) were also calculated.
In order to verify a measuring method with a laser scanner, a comparison with the vertical distribution of LAD measured by the stratified clipping method was conducted. Although PAD measured with the laser scanner overestimated LAD measured by the stratified clipping method by a factor of two (r²=0.98), the relation of 1:1 was found by LAD measured with the laser scanner and measured by the stratified clipping method (r²=0.94). The vertical distribution of LAD had a peak from 1 m to 2 m, and was well in agreement with the vertical distribution measured by the stratified clipping method. The three-dimensional distribution of LAD showed not only vertical distribution but also horizontal heterogeneity of canopy. ALIA calculated as an average of canopy was 57.5 degrees. In conclusion, the method with the laser scanner was able to measure the three-dimensional structure of forest.

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This paper describes effects of varied meteorological conditions on the grain filling periods, stabilities of yield and quality of winter wheat cultivars with different maturity characteristics (cv. Ayahikari, Norin61, Bandowase, Tsurupikari). In the field experiments, the meteorological treatments were made during the first heading time on 17 April 2001 and the middle heading time on 24 April 2000. Air temperature, global solar radiation and soil moisture were controlled using a rain shelter, cheesecloth and irrigation system. The growth speed and growth period of wheat grains varied among four winter wheat cultivars, depending on meteorological conditions. The growth speed increased within 18.4℃ of mean air temperature over the 30 days after the anthesis. On the other hand, it was found that the growth speed of wheat grains and the maximum number of wheat grains (Y_max) decreased greatly with the 44.4% interception of global solar radiation. Logistic functions were fitted to the relationship between the relative thousand-kernel-weight (Y/Y_max) and the total integrated temperature (ΣT_a) after heading for all treatment conditions.
The maximum weight of grains (Y_max) achieved at the harvest time varied somewhat clearly among four winter wheat cultivars and meteorological conditions. Multiple regression analysis showed that the grain yield (Y_max) of four wheat cultivars correlated positively with daily mean solar radiation. It was also found that the cultivar Ayahikari had a highly significant negative correlation between its grain weight and soil moisture. Namely, the grain weight of high soil moisture plot with pF=1.5 was lower by about 9% than that of a control plot with pF=3.5. On the other hand, the grain yield of cultivar Norin61 responded inversely to a wet environment, indicating that its grain weight was higher for high soil moisture and high wet-bulb temperature than for a dry environment. The grain yield of early varieties of Bandowase and Tsurupikari increased with the increasing temperature difference (T_d—T_w). Ash and protein contents of wheat grains in the restricted global solar radiation plot and higher temperature plot were higher than those for the control plot, independently of the four winter wheat cultivars.

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It was reported that optical remote sensing could estimate absorptance of solar radiation by rice communities. Both chlorophyll and nitrogen content in rice communities were also reported to be estimated by remote sensing with high correlation. The number of rice grains per m² is an important factor for yield prediction. A field experiment was conducted to make sure the possibility of remote sensing for estimation of the number of rice grains. Paddy rice communities were prepared by nitrogen fertilization to have a wide range of the number of grains. The relationship between vegetation index and chlorophyll content in rice communities was in high correlation. Furthermore the number of rice grains increased with chlorophyll content in rice communities. These results suggested the possibility of remote sensing for estimation of the number of rice grains. This suggestion was confirmed by the present study. The relationship between NDVI and the number of rice grains was in good correlation (r=0.88). The possibility of estimating the number of rice grains with remote sensing was verified.

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Recently, impacts of climate change on ecosystems have been of concern. In this study, the differences between the present type of natural vegetation distribution, which is derived from the national survey on the natural environment and the potential type of natural vegetation distribution estimated by a simulation model using the normals were analyzed to evaluate the risk to vegetation from climate change. The results of the analysis showed that natural vegetation and potential natural vegetation were different in some areas. Furthermore, the results of the analysis with projected potential natural vegetation using GCM data showed that the areas where natural vegetation and potential natural vegetation were different expanded. In such areas, the possibility that climate conditions will not be able to support present natural vegetation, was high. It is suggested that the areas with a high risk will expand.

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Evapotranspiration from a sugar cane field was observed during the summer season in the Miyako Islands. Interpolation was also conducted for the data deficit period by using the bulk transfer coefficient and evapotranspiration efficiency, which were represented as a function of solar radiation and soil water content. Evapotranspiration was 6.4 mm day^-1 in late June, and decreased gradually. It was under 3.5 mm day^-1 (100 W m^-2) at the end of October.

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