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Rainfall variability significantly influences plant productivity; including palm oil. This research aims to describe rainfall variability and its influence on oil palm productivity on Seram Island, Maluku Province. The data collected consists of rainfall, palm oil production data and supporting data. The analytical method used consists of generating rainfall data, analyzing extreme rainfall conditions and regression analysis to see the relationship between rainfall and palm oil productivity. The research results show that the El Nino rainfall anomaly at the research location in the 1992-2021 period occurred 8 times with a frequency of once every 2 - 6 years or an average of once every 3 years. La Nina occurs 7 times with a frequency of 1 - 10 years or an average of once every 4 years. The very extreme El Nino caused a reduction in rainfall at the research location by 888 mm or 40% of normal conditions, whereas the very extreme La Nina event resulted in an increase in rainfall of 1491 mm or 58% of normal conditions. Rainfall variability is very closely related to oil palm productivity with the regression equation Y = 94.05 - 0.1558x + 0.000083x 2 - 10 -8 x 3 and the accuracy level R 2 is 98.6%. [ABSTRACT FROM AUTHOR]

There is a well-known phenomenon in tree crops known as "biennial bearing," in which the fruit-bearing increases or de- creases every other year. Synchronization of biennial bearing has been more prevalent in olives of the Eastern Mediterranean region, which includes Jordan and Syria, rather than fluctuations associated with rainfall and other climatic conditions. This synchronization phenomenon is thought to have been accepted in the region since the time of ancient civilizations, but modern science has not been able to elucidate its mechanism. On the other hand, the biennial bearing and synchronization phenomena have significantly been disrupted since the beginning of the 21st century. The disappearance of biennial bearing and the reversal of synchronization can be observed since 2008 in Syria and 2015 in Jordan. These periods coincide with when the problems of refugee inflows into Syria due to the Iraq War and into Jordan due to the Syrian Civil War became apparent, respectively. Therefore, this study examines the hypothesis that social, political, and economic factors, which have been neglected in agronomy, have substantially influenced those phenomena in olive production. Field surveys and experiments are conducted in the Irbid governorate of Jordan, where olive production is the most dominant agricultural activity, with significant labor and consumer population inflows from the bordering parts of Syria. [ABSTRACT FROM AUTHOR]

Arid and semi-arid regions experience less rainfall and high evaporation rates and are very sensitive to land use transitions. Salt-induced soil degradation is one of the major constraints in arid and semi-arid regions of India. In India about 6.73 Mha land is salt affected out of which around 3.78 M ha is under sodic soils. Around 2.5 M ha area is covered under salt affected soils in Indo Gangetic Plains (IGP), the most fertile landmass. Besides infelicitous crop management practices, injudicious use of sodic water possess grave risks to soil health. High Residual Sodium Carbonate (RSC) restricts the natural drainage, a rationale to surface and subsurface sodicity development. On farm residue burning is also a burgeoning problem in the semi-arid region of IGP where rice-wheat cropping system is predominantly followed. Fathoming the twin problem of sub-surface sodicity and residue burning the column study in semi-controlled condition is being conducted under ICAR-Central Soil Salinity Research Institute (Karnal) and the Japan International Research Center for Agricultural Sciences (JIRCAS) collaborative project. The treatments consisted surface application of gypsum (SA), surface and sub-surface placement (50 cm below the surface) of rice straw residue and gypsum that is an imitation of sub-surface Cut-soiler assisted drains in field condition. The columns were irrigated with water having RSC <2 meql-1 and ~5 meql-1. The results showed that comparatively the higher reduction in soil pH was recorded in the columns irrigated with RSC <2 meql water as compared to ~5 meql under surface application of gypsum along with sub-surface application of gypsum and residue both. Consequently, the rice yield increase about 31% and 23% in the foresaid treatment as compared to control. Therefore, surface application of gypsum along with cut-soiler assisted sub-surface placement of amendments found promising in reclamation of sub-surface sodicity and increase rice yields under sodic soils. [ABSTRACT FROM AUTHOR]

This article explores the relationship between weather conditions and the population dynamics of the tobacco leaf eating caterpillar, Spodoptera litura, which is known to infest groundnut crops. The study was conducted in Anand, India during the kharif season of 2021. The researchers observed that the infestation of S. litura on groundnut crops occurred from July to October, with the number of larvae and the percentage of damaged plants decreasing as the crop matured. The study found that rainfall, relative humidity, and vapor pressure were positively correlated with the larval population of S. litura. This research provides valuable insights into the seasonal occurrence of this pest and its relationship with weather factors, which can help in developing strategies to mitigate its impact on groundnut production. [Extracted from the article]

Soil moisture is a key factor controlling vegetation construction and ecological restoration in arid and semiarid areas. Understanding its spatiotemporal patterns and influencing factors is essential for effective vegetation water management. In this study, we analyzed the spatiotemporal characteristics of black locust plants using field investigations and statistical analyses and determined the effects of the rainfall and plant characteristics on the soil moisture content (SMC) in a typical watershed in the Loess Plateau, China. The results show that the SMC increases with increasing distance from the tree trunk in the horizontal direction. The vertical profile of the SMC includes layers characterized by rapid decrease, decreased fluctuation, and slow increase. Temporal SMC changes exhibit higher variabilities in the surface layer than in deeper soil layers. Rainfall characteristics notably affect soil moisture. The influence of the rainfall amount is stronger than that of the rainfall duration and intensity. The diameter at breast height, tree height, and canopy width positively affects the soil moisture, whereas the leaf area index and canopy openness negatively affect it. The results of this study provide insights into soil moisture change mechanisms and theoretical references for sustainable plant water use management in arid and semiarid areas. [ABSTRACT FROM AUTHOR]

Due to rainfall and high temperatures, the Amazonian soil undergoes changes in its source material and leaching of base cations. This results in deep, infertile, and acidic soil. Aluminum present in acidic soil impairs plant growth and development by inhibiting root formation, enzymatic reactions, absorption, transport, and nutrient utilization. This study aimed to evaluate the effects of aluminum dosage on the metabolism of the oil palm Elaeis guineensis Jacq. The study was conducted in a greenhouse at the Federal Rural University of Amazonia. The experimental design was randomized, with five replications, in which dosages of 0, 10, 20, 30, and 40 mg L-1 aluminum chloride (AlCl3.6H2O) were administered. Electrolyte leakage, nitrate, nitrate reductase, free ammonium, soluble amino acids, proline content, and soluble proteins were analyzed in the leaves and roots of the oil palm. The highest concentration of aluminum was found in the roots. AlCl3 treatment at 40 mg L-1 increased electrolyte leakage, nitrate, ammonium, and proline concentrations in the roots, and amino acid concentrations in both the leaves and roots. Furthermore, a decrease in nitrate reductase enzyme activity was observed in the roots. This study demonstrates that the oil palm has mechanisms of tolerance to aluminum toxicity. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) confer both positive and negative effects on the plant symbionts, depending on the prevailing growth condition. We investigated the effect of concurrent variations in phosphorus and soil moisture on percentage root colonization (%RC), mycorrhizal growth response (MGR) and drought response index (DRI) of SAMMAZ-16 maize variety in timescale. The experimental factors were AMF inoculation (addition or no addition), P2O5 applications (30, 60 or 90 kg ha-1) and water regimes (100% and 50% of the soil’s field capacity introduced after 4WAS). The result shows that the overall %RC was 62.22% at 8 weeks after sowing (WAS) and 71.33% at 12 WAS. With 30 and 60 kg P2O5 ha-1 application a rate, %RC was significantly higher at 12 WAS than that of similar application rates at 8 WAS. However, %RC was not different between 8 WAS and 12 WAS in 90 kg P2O5 ha-1 application. AMF inoculation tended to equilibrate the shoot growth of the inoculated plants to that of non-inoculated plants that received 50% higher doses of P2O5 under amply watered conditions. Increasing phosphorus application progressively alleviated the negative mycorrhizal response of the plants at the early stage of growth (week 4) and in 50% FC category at the other sampling times. Higher doses of P2O5 application improved the DRI of the maize in both samplings but the trend was more consistent in AMF-inoculated plants. We conclude that AMF inoculation would be detrimental to the growth of SAMMAZ-16 when there is combined phosphorus and water stress factors. [ABSTRACT FROM AUTHOR]

This study examines the characteristics of extreme precipitation and its effect on bean yield in Rwanda from 1981 to 2017. Over the study area, two rainy seasons, March to May (MAM) and September to December (SOND), account for approximately 80% of total rainfall. The spatial distribution of rainfall over Rwanda revealed that the first three EOF modes of MAM rainfall vary by 72.72 percent over the study period, while the first three EOF modes of SOND rainfall vary by 57.48 percent. The spatial analysis of extreme precipitation reveals that during wet years, the majority of the country's western regions receive significantly more precipitation than the rest. Throughout the study period, the analysis revealed an increasing trend in all extreme precipitation indices. After 2009, a significant increase in the number of wet days (R1mm) and consecutive dry days (CDD) was observed, as was an increase in the number of consecutive wet days (CWD) after 2005. From 1981 to 1989, bean yield increased; however, after 1990, the trend became stationary and began to decline after 2012. Except for R1mm, CDD, and CWD, which showed a negative correlation, the correlation analysis revealed a positive relationship between extreme precipitation indices and bean yield. Despite the fact that there is a weak negative correlation between bean yield and CDD, CDD can be used as a predictor of bean yield due to the significant Granger causality test at the 95% confidence level. Farmers are advised to use alternative methods to increase soil moisture and water holding capacity during the CDD period to avoid yield loss. [ABSTRACT FROM AUTHOR]

Due to climate change, drought events will probably occur more frequently and be more intense. Therefore, effective drought monitoring and assessment is vital in developing knowledge of drought, drought adaptation, and mitigatory actions. Remote sensing has been widely used for monitoring drought in recent years. In the current research, three groups of remote sensing indices, i.e. vegetation, thermal and moisture indices, were applied to determine the correlation between them and the standardized precipitation index (SPI) as drought index for the growing season (April to September) from 1999 to 2005 for rangeland areas in the Alborz province of Iran. The results indicated that normalized difference vegetation index (NDVI) (with a correlation coefficient of 0.74) and land surface temperature (LST) (with a correlation coefficient of 0.67) had the highest correlations with rainfall. Therefore, it concluded that the assumed indices are suitable for drought monitoring for this land use. Temporal analysis of the results showed that the best correlations of remote sensing indices belonged to the 6- and 9-month SPI and indicated the effect of long-term rainfall on plant growth. [ABSTRACT FROM AUTHOR]

Ridge-furrow rainfall harvesting (RFRH) planting can improve crop productivity through enhancing water use efficiency. However, effects of long-term use of RFRH on soil erosion and soil quality in sloping farmland are not well understood. This experiment was conducted with a two-factor split plot design, with the main plot having a slope of 5° and 10°. The sub-plots followed three planting patterns: contour ridge-furrow planting without mulching (CK), contour ridge film mulching and furrow straw mulching (T1), and contour ridge film mulching and furrow no mulching (T2). The results showed that no significant effect on soil erosion was found under T1 and T2 on 5° slope. The total runoff and total erosion of T1 on 10° slope decreased by 82.8 and 92.0%, and that of T2 on 10° slope decreased by 34.5 and 83.1%, respectively, compared with CK. Soil water content in T1 and T2 significantly increased by 11.0 and 10.6%, respectively, compared with CK (p < .05). Soil quality index in T1 was the highest, followed by T2 under the same slope. Yield was increased in T1 and T2 significantly by 30.7 and 20.2%, respectively, compared with CK (p < .05). Our results show that contour ridge film mulching and furrow straw mulching can alleviate drought, water shortages, and soil erosion. [ABSTRACT FROM AUTHOR]

Background: Different factors affect vegetation changes in all areas. Pointing out the climate factors is an important issue when considering vegetation. Methods: In Taif province, we studied the vegetation changes in Al-Hada and Al-Shafa areas in the period from 2000 to 2018. The correlation between vegetation and climate factors in the previously mentioned areas has been studied in spring. Results: Using NDVI images, we found that the highest coverage was in 2013 with 11.23% in Al-Hada area, while the lowest coverage was in 2018 with 3.48% in Al-Shafa area. The information about the climate factors was obtained from NOAH model data from NASA Global Land Data Assimilation System with spatial resolution (1.0° and 0.25°). We found that temperature and rain precipitation had the greatest impact. Conclusion: The results indicated that this method had the potential to be a useful guide to identify the impact of these two factors on the vegetation in this area. [ABSTRACT FROM AUTHOR]

Climate change poses significant challenges to the production of oil palm as its output can be directly affected by abiotic stress, especially drought. Thus, this research was designed to investigate the effect of different water stress regimes on the physiology of oil palm seedlings to determine the optimum amount of water that should be applied. Three-month-old Tenera hybrid (Dura X Pisifera) oil palm seedlings were arranged in randomised completely block design (RCBD) and treated with four irrigation regimes: 100% ER (evapotranspiration replacement; well-watered), 75% ER (moderate water stress), 50% ER (high water stress) and 25% ER (severe water stress). Growth, carbon assimilation and biochemical parameters were recorded during the experiment. The results showed severe water stress decreased vegetative plant growth, leaf water potential, relative water content, leaf moisture content, stomatal conductance, transpiration rate, net photosynthesis, water use efficiency and fv/fm (maximum efficiency of photosystem II). The level of malondialdehyde (MDA) and proline increased under water stress. Regarding irrigation, 100% ER (control) was most effective on most parameters, but there was no significant difference to 75% ER. Thus, to optimise the water utilisation, supplying 75% water from soil field capacity on oil palm seedlings is the best option. [ABSTRACT FROM AUTHOR]

Oviposition patterns of the diamondback moth (DBM), Plutella xylostella L. (Lepidoptera: Plutellidae), differ between common cabbage (Brassica oleracea L. var. capitata) and Chinese cabbage (Brassica rapa L. var. pekinensis) (Brassicaceae) host plants. This study shows that the moth prefers to oviposit on adaxial rather than abaxial leaf surfaces and petioles of both host plants. More eggs were laid in leaf veins than on leaf laminas of both host plants, especially in Chinese cabbage, where 94.6% of eggs were laid in veins. On Chinese cabbage, very few eggs were laid in clusters (≥2 eggs), whereas on common cabbage approximately 30% of eggs were laid in groups of 2 or more eggs. Removal of wax from common cabbage leaves dramatically increased the number of eggs laid singly on the leaf lamina of treated plants, suggesting that leaf waxes affect how eggs are distributed by ovipositing DBM. Eggs were most susceptible to removal by rainfall from the plant surface immediately (<1 h) after oviposition and when close to hatching (>72h old) whereas they were least susceptible 24 h after oviposition. Eggs laid on common cabbage plants were more susceptible to simulated rainfall than eggs laid on Chinese cabbage plants. On common cabbage plants, egg susceptibility to rainfall on different plant parts ranked adaxial leaf surfaces>petioles = abaxial leaf surfaces>stem, but there was no difference in egg susceptibility to rainfall on the various plant parts of Chinese cabbage. Furthermore, on common cabbage plants, eggs laid on both adaxial and abaxial leaf surfaces were afforded significant protection from the effects of rainfall by leaves higher in the plant canopy. On common cabbage plants, oviposition patterns reduce the potential impact of rainfall on eggs, possibly reducing the effect of this important abiotic mortality factor in the field. [ABSTRACT FROM AUTHOR]

Increased frequency of heavy rainfall caused by climate change may affect nutrient transport from forests and agricultural lands into downstream rivers. However, little information is available on how the effects of land cover on nutrient concentrations in the downstream rivers change depending on hydrological conditions. To elucidate this, we investigated the effects of changes in precipitation and river discharge on the relationship between river nutrient concentrations (total nitrogen, total phosphorus, nitrate, and phosphate) and land cover in eight subbasins of the Hii River basin, western Japan. We hypothesized that coniferous forests and agricultural lands including poorly managed ones, which require thinning and fertilizer management, respectively, contribute to increases in nutrient concentrations in downstream rivers during storms. Linear mixed‐effects model analyses based on 18‐year observation data were used for testing the hypothesis. Results revealed that the slopes of the multiple regression analysis between nutrient concentrations and coniferous and broad‐leaved forest area ratios were negative and decreased with increasing daily precipitation. This suggests that forests contributed to the dilution of river nutrient concentrations during storms regardless of whether they were coniferous or broad leaved. In contrast, the slope of regression between nutrient concentrations and agricultural area ratio revealed the opposite trend, indicating that even a small percentage of agricultural area makes a large contribution to increases in nutrient concentrations as precipitation increases. Our results imply that storm runoff in response to rainfall results in an elevated supply of nitrogen and phosphorus attached to arable soils to the river. Key Points: This study examined how forest and anthropogenic lands change downstream nutrient concentrations depending on the hydrological conditionsBoth conifer plantations and broad‐leaved forests buffered increases in river nutrient concentrations during stormsA small area of anthropogenic land covers made a large contribution to the increased nutrient concentrations as precipitation increased [ABSTRACT FROM AUTHOR]

Abstract Perennial crops offer the opportunity to harvest from the same plant many times over several years while reducing labor and seed costs, reducing emissions and increasing biomass input into the soil. We use system dynamics modeling to combine data from field experiments, crop modeling and choice experiments to explore the potential for adoption and diffusion of a sustainable agriculture technology in a risky environment with high variability in annual rainfall: the perennial management of pigeonpea in maize-based systems of Malawi. Production estimates from a crop model for the annual intercrop system and data from field experiments on ratooning for the perennial system provided the information to create a stochastic production model. Data from choice experiments posed by a farmer survey conducted in three Malawi districts provide the information for parameters on farmers' preferences for the attributes of the perennial system. The perennial pigeonpea technology appeared clearly superior in scenarios where average values for maize yield and pigeonpea biomass production were held constant. Adoption was fastest in scenarios where relatively dry growing seasons showcased the benefits of the perennial system, suggesting that perennial management may be appropriate in marginal locations. The potential for adoption was reduced greatly when stochasticity in yields and seasons combine with significant social pressure to conform. The mechanism for this is that low yields suppress adoption and increase disadoption due to the dynamics of trust in the technology. This finding is not unique to perennial pigeonpea, but suggests that a critical factor in explaining low adoption rates of any new agricultural technology is the stochasticity in a technology's performance. Understanding how that stochasticity interacts with the social dynamics of learning skills and communicating trust is a critical feature for the successful deployment of sustainable agricultural technologies, and a novel finding of our study. Highlights • Dynamic models of adoption can use choice experiments to parameterize preferences • Perennial pigeonpea shows strong adoption potential, even on marginal land in Malawi • Variable performance of a new technology can suppress adoption due to loss of trust [ABSTRACT FROM AUTHOR]

Highlights • Land use and plant traits are important determinants of grassland drought responses. • The key drivers of grassland decline and recovery differed. • Grasslands response to land use variables differed between drought and wet phases. Abstract Climate change is expected to increase the frequency and intensity of drought globally with potentially significant consequences for grasslands. We examined grassland responses to a long-term drought on the Darling Downs, eastern Australia, using the Enhanced Vegetation Index (EVI), a remotely sensed measure of primary productivity. This extreme drought period had rainfall deficits comparable to the hottest and driest projected climate change scenarios for 2030 and was followed by extreme rainfall. This juxtaposition allowed investigation of grassland dynamics (decline and recovery) under extreme climatic variability. Our aim was to determine whether factors associated with grassland decline during extreme drought are the same as those that drive recovery post drought. There is limited knowledge about whether the determinants of grassland decline and recovery are consistent, but this information is important for understanding how best to reduce grassland decline, without inhibiting recovery. We calculated EVI (Enhanced Vegetation Index) trends at 2549 grassland sites situated in an agricultural landscape and used boosted regression trees to model these against multiple hydro-climatic and land use factors. As anticipated, hydro-climatic variables were key drivers of EVI trends in both the drought and wet phases, with higher soil moisture corresponding to less decline in the drought phase and enhanced recovery in the wet phase; however, land use and plant trait variables were also important predictors of EVI trends. Higher proportions of dryland agriculture in the local landscape, high C3:C4 ratios and lower proportions of woody vegetation in the local landscape were associated with negative EVI trends (i.e. greater decline) during drought, but had inverse or negligible effects during the post drought recovery phase. Our results suggest that mitigating decline and fostering grassland recovery following drought requires considering multiple hydro-climatic, land use and plant trait drivers and how their importance changes under drought and wet phases. [ABSTRACT FROM AUTHOR]

Climate change, increased temperatures and imbalanced precipitation distributions will potentially increase the local drought risk in certain areas. Drought assessment can identify the hidden dangers of drought and provide a theoretical basis for disaster prevention and mitigation. In this paper, a new agricultural drought risk assessment method proposed from the perspective of grain yield. The first principal components of precipitation, temperature, humidity and soil moisture represent hazard factors. The sensitive yield, which represents the sensitivity, was separated from the grain yield using a regression method. Additionally, the trend component of the grain yield represents the adaptive capacity, and the crop planting area represents exposure. Based on these definitions, the concepts of unit drought risk and regional drought risk are proposed. Four cities in Heilongjiang Province, which has the highest grain yield of any province in China, were used as application examples, and the spatial and temporal variation in the agricultural drought risk were analyzed. Application example show that the method for evaluating agricultural drought presented in this paper is reasonable in a statistical sense. The process for calculating sensitivity and adaptability shows that this method is suitable for arid and semi-arid areas, where grain yield is sensitive to hazard factors, and areas where grain yield has a certain trend. [ABSTRACT FROM AUTHOR]

Highlights • Develop a probabilistic forecasting model for canopy temperature by weather variables. • Allow model parameter to vary periodically for better model performance. • Compare the model performances with existing models by case studies. • Test contribution of individual predictors by evaluating performance of sub-models. Abstract Continuous measurement of canopy temperature is an important indicator of plant water status of crops and the ability to predict canopy temperature will assist in the implementation of this technology for guiding crop irrigation scheduling. By noting that canopy temperature is related to its environmental weather variables which change over time of the day and have different effect or contribution to canopy temperature, this paper presents a probabilistic model to predict canopy temperature by using weather variables which can be obtained from weather model predictions. Unlike the existing models which consider only the linear correlation, the proposed model allows the model parameters to vary according to a periodic function which is designed to capture the variation over the time of the day. The continuity of parameter changes is guaranteed by varying the model parameters periodically and smoothly. Two case studies using cotton experiments from Australia and the United States are conducted to compare the model performance with the existing published models. Using the predictions of canopy temperature an index of crop stress is also predicted in order to evaluate its influence in the irrigation scheduling. Results show that the proposed model is superior to the existing published models in its ability to predict canopy temperature into the future and has utility in assessing when crop stress will occur, to assist with irrigation scheduling. Further evaluations suggest that the air temperature is a dominate weather variable for forecasting canopy temperature but the inclusion of the other weather variables still improves the forecast. [ABSTRACT FROM AUTHOR]

Rain recharges soil water storages and either percolates downward into aquifers and streams or is returned to the atmosphere through evapotranspiration. Although it is commonly assumed that summer rainfall recharges plant-available water during the growing season, the seasonal origins of water used by plants have not been systematically explored. We characterize the seasonal origins of waters in soils and trees by comparing their midsummer isotopic signatures (δ2H) to seasonal isotopic cycles in precipitation, using a new seasonal origin index. Across 182 Swiss forest sites, xylem water isotopic signatures show that summer rain was not the predominant water source for midsummer transpiration in any of the three sampled tree species. Beech and oak mostly used winter precipitation, whereas spruce used water of more diverse seasonal origins. Even in the same plots, beech consistently used more winter precipitation than spruce, demonstrating consistent niche partitioning in the rhizosphere. All three species' xylem water isotopes indicate that trees used more winter precipitation in drier regions, potentially mitigating their vulnerability to summer droughts. The widespread occurrence of winter isotopic signatures in midsummer xylem implies that growing-season rainfall may have minimally recharged the soil water storages that supply tree growth, even across diverse humid climates (690–2068 mm annual precipitation). These results challenge common assumptions concerning how water flows through soils and is accessed by trees. Beyond these ecological and hydrological implications, our findings also imply that stable isotopes of δ18O and δ2H in plant tissues, which are often used in climate reconstructions, may not reflect water from growing-season climates. [ABSTRACT FROM AUTHOR]

The rainfall and temperature conditions are evaluated for the first time during the 1989–2006 period, in six main cocoa production areas (Abengourou, Agboville, Daloa, Dimbokro, Guiglo, and Soubre) of Côte d'Ivoire using data from SODEXAM (ground-based observation) and the ex-CAISTAB. Statistical analysis shows an important sensitivity of cocoa production to rainfall conditions in all regions. It is worth noting that only the major rainy season from April to July and the rainfall amount of the little dry season from August to September affect the cocoa production for an 80% confidence level. This influence varies from one cacao production area to another. Moreover, the effects related to temperature on the cocoa yield seem to represent a smaller contribution of climate impact than those related to precipitation during the studied period. The temperature change remains in the acceptable range of values, between 25°C and 29°C, which is a favorable condition for cocoa growing. These findings are obtained despite the significant contributions from nonclimatic factors, to year-to-year variability in cocoa production. [ABSTRACT FROM AUTHOR]

Analysis of anthropometric evidence about conscripts born in the region of València (Mediterranean Spain) between 1850 and 1949, in conjunction with high-resolution gridded climatic data and gis analysis, finds that modern agriculture within a warm climate was conducive not only to regional economic development but also to improvements in health, as signified by increased height. The most benefits accrued to those living in irrigated rural areas. Results show a strong influence of summer and autumn weather on growth, overlapping with the production of food. In irrigated areas, warm temperatures mattered much more than rainfall, whereas in nonirrigated areas, rainfall was crucial for the development of well-being. [ABSTRACT FROM AUTHOR]

An experiment was carried out to identify the effect of season on various leaf parameters of Kuliana lime during 2016-17 at Horticultural Research Station, Department of Fruit Science and Horticulture Technology, O.U.A.T., Bhubaneswar. The rainy season recorded the maximum leaf fresh weight (0.39 g), leaf dry weight (0.18 g), leaf area (16.19 cm2) whereas spring season have greater production of chlorophyll-a (1.19 mg per g of FW), chlorophyll-b (0.61 mg per g of FW) and total chlorophyll (1.81 mg per g of FW). Rainy season flush showed the maximum leaf area, leaf fresh weight and dry weight, due to the better availability of soil moisture and high relative humidity of atmosphere resulting in low transpiration losses which perhaps favoured the better leaf growth. Though spring season have the most favourable climatic condition but carbohydrate in spring flush leaves were might utilized mainly to support reproductive growth hence there was reduction in the dry weight of leaves. [ABSTRACT FROM AUTHOR]

Summary: Rainfall variability is a major determinant of soil moisture, but its influence on vegetation structure has been challenging to generalize. This presents a major source of uncertainty in predicting vegetation responses to potentially widespread shifts in rainfall frequency and intensity. In savannas, where trees and grasses coexist, conflicting lines of evidence have suggested, variously, that tree cover can either increase or decrease in response to less frequent, more intense rainfall. Here, we use remote sensing products and continent‐wide soil maps for sub‐Saharan Africa to analyze how soil texture and fire mediate the response of savanna tree cover to rainfall climatology. Tree cover increased with mean wet‐season rainfall and decreased with fire frequency, consistent with previous analyses. However, responses to rainfall intensity varied: tree cover dramatically decreased with rainfall intensity on clayey soils, at high rainfall, and with rainfall spread over longer wet seasons; conversely, on sandy soils, at low rainfall, and with shorter wet seasons, tree cover instead increased with rainfall intensity. Tree cover responses to rainfall climatology depend on soil texture, accounting for substantial variation in tree cover across African savannas. Differences in underlying soils may lead to divergent responses of savannas to global change. [ABSTRACT FROM AUTHOR]

Action is needed to face the global threat arising from inconsistent rainfall, rise in temperature, and salinization of farm lands which may be the product of climate change. As crops are adversely affected, man and animals may face famine. Plants are severely affected by abiotic stress (drought, salinity, alkalinity, and temperature), which impairs yield and results in loss to farmers and to the nation at large. However, microbes have been shown to be of great help in the fight against abiotic stress, via their biological activities at the rhizosphere of plants. The external application of chemical substances such as glycine betaine, proline, and nutrients has helped in sustaining plant growth and productive ability. In this review, we tried to understand the part played by bioinoculants in aiding plants to resist the negative consequences arising from abiotic stress and to suggest better practices that will be of help in today’s farming systems. The fact that absolute protection and sustainability of plant yield under stress challenges has not been achieved by microbes, nutrients, nor the addition of chemicals (osmo-protectants) alone suggests that studies should focus on the integration of these units (microbes, nutrients, chemical stimulants, and osmo-protectants) into a strategy for achieving a complete tolerance to abiotic stress. Also, other species of microbes capable of shielding plant from stress, boosting yield and growth, providing nutrients, and protecting the plants from harmful invading pathogens should be sought. [ABSTRACT FROM AUTHOR]

The purpose of this short paper is to examine the vintage charts from 1949 to 2014 for Bordeaux and Burgundy regions and apply Ashenfelter’s models to estimate the relationship between vintage and weather and compare the results between Bordeaux and Burgundy. The results show that the impact of temperature during the growing season and rain during the harvest season is similar in Bordeaux and Burgundy but also for red and white wines. [ABSTRACT FROM AUTHOR]

Abstract: The ability of plants to survive drought or waterlogging constitutes an important niche parameter, which might be particularly significant in explaining species coexistence in the species‐rich and seasonally dry Cape Floristic Region of South Africa. However, the degree of physiological adaptation and specialization to these eco‐hydrological parameters (the fundamental niche) cannot be readily inferred from correlative studies based on species distributions and spatial variation in environmental parameters (the realized niche). We used an ex situ greenhouse experiment to compare the fundamental hydrological niches (different mean annual precipitation, rainfall seasonality and soil drainage) of six eco‐hydrologically divergent African Restionaceae species. Juvenile plants were subjected to six different watering treatments, ranging from no watering to waterlogging, to determine drought and waterlogging susceptibility and optimal growth conditions. We used the rate of biomass accumulation and survival rate as response measures. We found that species from dry and mesic (but well‐drained) habitats had optimal or near‐optimal growth at benign conditions (under which most restio species grow well). All species performed worse when droughted and died when not watered. Species from dry habitats tended to perform better (assessed in growth) than species from wet habitats under droughting. Species from wet habitats performed best when waterlogged, whereas species from dry habitats performed very poorly when waterlogged – thus showing that realized and fundamental niches covaried at the wet end of the hydrological gradient. We conclude that eco‐hydrological parameters are part of the fundamental niche, and fundamental and realized species niches are approximately correlated along them. The distribution of wet habitat species appears not to reflect their drought tolerance, suggesting that it may not be predicted by bioclimatic variables, but rather by soil drainage characteristics. [ABSTRACT FROM AUTHOR]

Abstract: In ecosystems subject to regular canopy fires, woody species have evolved two general strategies of post‐fire regeneration. Seeder species are killed by fire and populations regenerate solely by post‐fire recruitment from a seed bank. Resprouter species survive fire and regenerate by vegetative regrowth from protected organs. Interestingly, the abundance of these strategies varies along environmental gradients and across regions. Two main hypotheses have been proposed to explain this spatial variation: the gap dependence and the environmental‐variability hypotheses. The gap‐dependence model predicts that seeders are favoured in sparse vegetation (vegetation gaps allowing effective post‐fire recruitment of seedlings), while resprouters are favoured in densely vegetated sites (seedlings being outcompeted by the rapid crown regrowth of resprouters). The environmental‐variability model predicts that seeders would prevail in reliable rainfall areas, whereas resprouters would be favoured in areas under highly variable rainfall that are prone to severe dry events (leading to high post‐fire seedling mortality). We tested these two models using distribution data, captured at the scale of quarter‐degree cells, for seeder and resprouter species of two speciose shrub genera (Aspalathus and Erica) common in fire‐prone fynbos ecosystems of the mediterranean‐climate part of the Cape Floristic Region. Contrary to the predictions of the gap‐dependence model, species number of both resprouters and seeders increased with values of the Normalized Difference Vegetation Index (a widely used surrogate for vegetation density), with a more marked increase for seeders. The predictions of the environmental‐variability hypothesis, by contrast, were not refuted by this study. Seeder and resprouter species of both genera showed highest richness in environments with high rainfall reliability. However, with decreasing reliability, seeder numbers dropped more quickly than those of resprouters. We conclude that the environmental‐variability model is better able to explain the abundance of woody seeder and resprouter species in Southern Hemisphere fire‐prone shrublands (fynbos and kwongan) than the gap‐dependence model. [ABSTRACT FROM AUTHOR]

This study examines the MODIS time series NDVI datasets to detect greenness regeneration over Western Rajasthan and the Gujarat region of India. Time series analysis was applied to 17-years (2000-2016). MODIS NDVI satellite data product. Rainfall data for the same period were also analyzed to understand its impact over vegetation. NDVI time series datasets of MODIS 16-day composite proved sufficient for deriving statistically significant trend values for identifying areas of change in vegetation cover. Areas showing positive changes in NDVI trend was clearly correlated with areas which were brought under irrigational network over these areas, indicating an increase in vegetation, due to availability of water supply. Trends in NDVI were also compared with the trends in rainfall over the selected locations from Gujarat and Western Rajasthan. NDVI was positively correlated with the rainfall in both the regions. The NDVI time series trend analysis successfully detected the changes in greenness regeneration areas in Gujarat and western Rajasthan. [ABSTRACT FROM AUTHOR]

Historical data (2001-02 to 2016-17) on different meteorological parameters, viz. maximum temperature, minimum temperature and rainfall of Bathinda representing southwest Punjab were analyzed. Data indicate that the maximum temperature decreased ( -0.070°C year-1) during the wheat growing season (October to March) at Bathinda but the minimum temperature and rainfall increased by 0.0470C year-1 and 0.160 mm year-1, respectively. Maximum temperature indicates a decreasing trend during January, February and March at Bathinda. Increasing trend in minimum temperature during January and February and decreasing trend during March were observed. Increasing trend of rainfall was also observed during January, February and March. No clear cut relationships were observed between different meteorological parameters and grain yield. Comparison of the highest (2016-17) and lowest (2010-11) yield years indicates that lowest yield was observed when high rainfall was recorded and vice-versa. [ABSTRACT FROM AUTHOR]

The splash erosion characteristics of the herbaceous-dominant area in northern China remain uncertain. A total of 21 plots (3-m wide × 3-m long) were installed to investigate splash characteristics under different vegetation coverages (0%, 5%, 10%, 20%, 40%, 60%, and 80%) and rainfall intensities (40, 80, and 120 mm/h) using an artificial simulated rainfall device and an improved splash tray. Splashed particles were collected and analyzed for mass and size distribution. This study demonstrated that a vegetation coverage of 40% would help protect soil from splash erosion. Total splash amount generally decreased exponentially with increasing vegetation coverage and splash distance, but rose with increasing rainfall intensity. Vegetation coverage played a more important role in the mass-weighted average splash distance, with a significant Pearson correlation of −0.934 ( p  ˂ 0.01), compared to the rainfall intensity, with no significant correlation ( p  > 0.05). Moreover, splashed particles were finer than the original soil matrix because finer soil particles (clay, fine silt, and coarse silt) were transported preferentially by raindrops, and almost all mean weight diameters were lower than that of the soil matrix. Coarse silt showed the largest mass percentage at all splashed distances relative to the least mass percentage of coarse sand. The mass percentages of clay, fine silt, and coarse silt were generally positively correlated with vegetation coverage and splash distance and negatively correlated with rainfall intensity ( p  ˂ 0.05). Furthermore, the opposite was true for fine and coarse sand ( p  ˂ 0.05). These results could facilitate the further understanding of splash erosion characteristics and provide some suggestions for erosion control practices in northern China where herbaceous plants are important ingredients. [ABSTRACT FROM AUTHOR]

Rainfall has enormous impact on weather and climate. An investigation on impact of rainfall on coconut productivity was taken place in Kozhikode and Malappuram districts of Kerala, to identify the variation in coconut production on an account of secondary data based on rainfall collected for a time period from 1991 to 2015 (25 years). Panel data analysis revealed that rainfall during 3rd (July-September) and 4th (October-December) quarters was found to have signifcant negative impact on coconut production. Amount of rainfall observed during 1st (Januvary-March) and 2nd (April-June) quarters has positive non- significant impact on coconut production. The growth trend of rainfall showed an increasing trend in Kozhikode district whereas Malappuram district had a decreasing trend over the years. [ABSTRACT FROM AUTHOR]

This study mathematically correlates intensity of cotton leaf curl virus (CLCuV) with environmental factors (i.e. temperature, rainfall and humidity) and whitefly population in the agriculture system of Pakistan. It has been concluded that humidity and rainfall were directly correlated with the disease. Vector (whitefly) population was the third most influential factor in defining CLCuV intensity, which was also strictly associated with the mean monthly temperature of Pakistan. Mathematical interrelation developed in this study has a capability to predict disease intensity of future months. Therefore, it will be helpful to agriculturists for controlling the viral infection among agricultural areas of Pakistan. The study strongly recommends the immediate practice of measures controlling vector populations just after the detection of small elevations in mean monthly temperature. [ABSTRACT FROM AUTHOR]

Understanding the influences of rainfall and temperature on soil water and the grain production of winter wheat (Triticum aestivum L.), is of great importance to ensure the sustainability of food production on the Loess Plateau of China. Based on calibration and evaluation, the Environmental Policy Integrated Climate (EPIC) model was employed to determine the response of soil water and winter wheat to rainfall and temperature changing over the last 30 years in different regions. Results showed that (1) the EPIC model simulated soil water content well in 0-2 m soil, with a relative root mean square error (RRMSE) value of 6.0~14.0%, and the mean value of R2 was 0.824, which was similar to the value of ME (0.815); (2) rainfall decreased 13.6-24.9% more from 2001 to 2010 than it did during 1961-2000, while its minimum and maximum temperature increased 1.00-1.55 °C and 0.30-0.84 °C respectively, in comparison with 1961-2000; (3) both the increase of maximum temperature and the decrease of rainfall were harmful to the production of winter wheat. Contrarily, the increase of minimum temperature was beneficial to the production of winter wheat on the Loess Plateau of China. Furthermore, due to rainfall decreasing, the winter wheat yield of Luochuan, Changwu, Yuncheng, and Yan'an decreased by 8.5%, 7.6%, 11.7%, and 12.3%, respectively. Because of the rising of the maximum temperature, winter wheat yield decreased 6.4%, 6.8%, 7.2%, and -3.0%, respectively. On the other hand, the increase of the minimum temperature raised the winter wheat yield of 8.8%, 10.2%, 1.5%, and 12.0%, respectively. Climate change, either precipitation reduction or temperature increase, decreased soil water in the dry land winter wheat field. Therefore, more water-saving technologies are needed to adapt to climate change, to store and use water sources more effectively in semi-arid regions. Though precipitation reduction and maximum temperature increase produced negative impacts on winter wheat yield, the uptrend in minimum temperature is better for increasing the winter wheat yield, which can be used by farmers and governments to adapt to climate change, by adjusting planting time properly. [ABSTRACT FROM AUTHOR]

The aim of the present study was to establish the pretability, productivity and economical efficiency of the white lupine with low alkaloids content culture in the specific agro-climatic conditions of the hilly area of Transylvania. The experimental studies were carried out during the April-August period of 2018 and consisted in setting up a white lupine culture of Amiga variety (variety improved in Poland, considered free of alkaloids and other anti-nutritional compounds), on an area of 0.87 hectares, in Sălaj county, Romania. By analyzing the obtained data it results that the white lupine Amiga variety behaves well in the pedoclimatic conditions of the hilly area of Transylvania, reaching out yields of 2942 kg grains / ha, even in the context of less favorable climatic conditions which labeled the year of 2018 (rainfall excess during the flowering and pod development stage). The production expenses related to one beans ton was 207.07 euro / ton of grains, being lower with ca. 91% compared to the price of acquiring one ton soybean meals (396,14 euro /ton - the market price of the September month of 2018). The production costs related 1 kg of crude protein were lower with 30.4% in lupine compared to soybean meals. Nevertheless, it must be stated the fact that the proteins of the white lupine beans are showing a lower biological value comparatively to those derived from soybean meals. The pretability to the natural conditions of the Transylvania area, the grains yield level, the production expenses relatively low warrant us to recommend the Amiga variety of the white lupine as a perspective variety with high yields, still requiring the assessment for a longer period, comparing to other white lupine varieties homologated in Europe. [ABSTRACT FROM AUTHOR]

A current challenge for ecological research in agriculture is to identify ways in which to improve the resilience of the soil food web to extreme climate events, such as severe rainfall. Plant species composition influence soil biota communities differently, which might affect the recovery of soil food web after extreme rainfall. We compared the effects of rainfall stress up on the soil microbial food web in three planting systems: a monoculture of the focal species Zanthoxylum bungeanum and mixed cultures of Z . bungeanum and Medicago sativa or Z. bungeanum and Glycine max . We tested the effect of the presence of a legume on the recovery of trophic interactions between microorganisms and nematodes after extreme rainfall. Our results indicated that all chemical properties of the soil recovered to control levels (normal rainfall) in the three planting systems 45 days after exposure to extreme rain. However, on day 45, the bulk microbial community differed from controls in the monoculture treatment, but not in the two mixed planting treatments. The nematode community did not fully recover in the monoculture or Z . bungeanum and M. sativa treatments, while nematode populations in the combined Z. bungeanum and G. max treatment were indistinguishable from controls. G. max performed better than M. sativa in terms of increasing the resilience of microbial and nematode communities to extreme rainfall. Soil microbial biomass and nematode density were positively correlated with the available carbon and nitrogen content in soil, demonstrating a link between soil health and biological properties. This study demonstrated that certain leguminous plants can stabilize the soil food web via interactions with soil biota communities after extreme rainfall. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The aims of this study were to (1) estimate current rates of woody encroachment across African savannas; (2) identify relationships between change in woody cover and potential drivers, including water constraints, fire frequency and livestock density. The found relationships led us to pursue a third goal: (3) use temporal dynamics in woody cover to estimate potential woody cover. Location: Sub‐Saharan African savannas. Methods: The study used very high spatial resolution satellite imagery at sites with overlapping older (2002–2006) and newer (2011–2016) imagery to estimate change in woody cover. We sampled 596 sites in 38 separate areas across African savannas. Areas with high anthropogenic impact were avoided in order to more clearly identify the influence of environmental factors. Relationships between woody cover change and potential drivers were identified using linear regression and simultaneous autoregression, where the latter accounts for spatial autocorrelation. Results: The mean annual change in woody cover across our study areas was 0.25% per year. Although we cannot explain the general trend of encroachment based on our data, we found that change rates were positively correlated with the difference between potential woody cover and actual woody cover (a proxy for water availability; p < .001), and negatively correlated with fire frequency (p < .01). Using the relationship between rates of encroachment and initial cover, we estimated potential woody cover at different rainfall levels. Main conclusions: The results indicate that woody encroachment is ongoing and widespread across African savannas. The fact that the difference between potential and actual cover was the most significant predictor highlights the central role of water availability and tree–tree competition in controlling change in woody populations, both in water‐limited and mesic savannas. Our approach to derive potential woody cover from the woody cover change trajectories demonstrates that temporal dynamics in woody populations can be used to infer resource limitations. [ABSTRACT FROM AUTHOR]

Rainfall analysis of important plantation and spices producing districts such as The Nilgiris (Tamil Nadu), Kodagu (Karnataka) Idukki (Kerala) and Wayanad (Kerala) with 100 years data (1901 to 2000) obtained from the India Meteorological Department (IMD), Pune indicated that mean annual rainfall were 1839.7 mm, 2715.7 mm, 2979.4mm and 3381.0 mm with a coefficient of variation (CV) of 16.0%, 17.0%, 25.8% and 19.6%, respectively. The contribution of southwest monsoon(June-September) to the annual rainfall in these districts were 80.3% (Wayanad), 78.9% (Kodagu), 65.2% (Idukki) and 56.3% (The Nilgiris) with corresponding CV of 24.1%, 20.6%, 32.5%, and 24.6%, respectively. The declining trend in mean annual rainfall was noticed for Idukki, Wayanad and The Nilgiris, whereas, for Kodagu, it was stable. The change was significant in Wayanad and The Nilgiris. Similar trend was also observed for the southwest monsoon rainfall. The maximum decline in annual and southwest monsoon rainfall was noticed in The Nilgiris followed by Wayanad. Pre and post monsoon rainfall receipts were comparatively less with high inter-annual variations. The pre-monsoon (March-May) receipt and its coefficient of variation (CV) was 252.4 mm & 20.6% (Kodagu), 360.9 mm & 36.5% (Idukki), 251.7 mm & 36.6% (The Nilgiris) and 274.2 mm & 54.2% (Wayanad) 252.2 mm. The post monsoon (October-December) rain was maximum in Idukki 548.1 mm (CV 27.9%) followed by The Nilgiris 503.4 mm(CV 31.3%), Wayanad, 333.1 mm(CV 37.8%) and Kodagu 310.5 mm (CV 32.7%). In all these districts there was a declining trend in the pre-monsoon rain with maximum decline in The Nilgiris. Similar declining trend was also observed in post-monsoon rain except for The Nilgiris, where the trend has been increasing. Overall, the study gives an indication that there was a spatial and temporal variation in rainfall amounts. The maximum decline in annual rainfall and the southwest monsoon was observed in The Nilgiris and Wayanad. July was the rainiest month in all the districts studied. Significant negative trend was asscoaited with The Nilgiris for January, May, June, July and August months. Whereas, in Kodagu, no significant trend was observed for mean monthly rainfall, except for August. In Idukki, significant negative changes were noticed for January, March, October and December rainfall. Monthly rainfall of January, March, April and July monthly rainfall were showed significant negative trend in Wayanad. These negative trends across important plantation and spices producing districts of the Western Ghats would affect not only the agricultural economy of this sector but also water resources. [ABSTRACT FROM AUTHOR]

Climate change has altered global rainfall amounts and seasonality. Rainfed crops are particularly dependent on foreseeable rainfall, thus yields of maize, wheat and sorghum have decreased globally. Rainfed maize is the cornerstone of the agriculture in Mexico and the nutrition base of as many as twenty million people. Despite its relevance, the risk that climate change represents for this economic activity has not been studied in our country. We evaluated the link between rainfall variability and maize yields in Mexico across three different time periods: the present, the past 30 years and the remainder of this century (future) with RCPs scenarios. We found that rainfed agriculture was distributed as a function of the dry-season length, occurring in areas with a 4–9 months dry season, thus climate change may alter not only agricultural yields, but also the spatial distribution of land uses. There was a linear correlation (r = 0.45) between mean annual precipitation and rainfed maize production nationally for the period 1980–2012. The correlation was stronger (r = 0.91) during 2005–2012 when high-resolution data were available for the analysis. Correlation values were not homogeneously distributed within the country, although the minimum correlation was 0.35. In the future scenarios, yields were predicted to either not change or to decrease by as much as 10%. The strongest negative impacts were predicted across the Northeast and the South of the country, where yields declined by up to 30% in all scenarios. [ABSTRACT FROM AUTHOR]

Arid pomegranate ( Punica granatum ) orchards are frequently rainfed. In these systems, orchard managers might be able to manipulate a stand’s canopy structure ( e.g. , thinning, pruning) to improve rainfall water input to the soil. The aim of this research was to determine how changes in management activities in rainfed pomegranate orchards in arid regions of Central Iran affects rainfall partitioning into throughfall, stemflow, and rainfall interception loss. We monitored gross rainfall, throughfall, stemflow and rainfall interception loss in three stands with varying levels of thinning and pruning. Management practices sufficiently altered the stand and canopy structure of pomegranate orchards to impact the quantity and pathway (throughfall v. stemflow) of rainfall reaching the ground. Decreases in tree height, canopy cover, crown length and LAI were correlated to a significant increase in rainfall reaching the forest floor. Results indicate that orchard managers may be able to prune 40% of the live crown and thin 70% of the stand if the objective it to significantly increase water inputs into the soil. Future research should focus on the impact of canopy management on soil moisture content and soil evaporation and transpiration. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fire is a fundamental process in savannas and is widely used for management. Pyrodiversity, variation in local fire characteristics, has been proposed as a driver of biodiversity although empirical evidence is equivocal. Using a new measure of pyrodiversity (Hempson et al.), we undertook the first continent-wide assessment of how pyrodiversity affects biodiversity in protected areas across African savannas. The influence of pyrodiversity on bird and mammal species richness varied with rainfall: strongest support for a positive effect occurred in wet savannas (> 650 mm/year), where species richness increased by 27% for mammals and 40% for birds in the most pyrodiverse regions. Range-restricted birds were most increased by pyrodiversity, suggesting the diversity of fire regimes increases the availability of rare niches. Our findings are significant because they explain the conflicting results found in previous studies of savannas. We argue that managing savanna landscapes to increase pyrodiversity is especially important in wet savannas. [ABSTRACT FROM AUTHOR]

According to the data of analytic trees, an empirical equation of tree growth was constructed, with annual growth as variable and time and annual precipitation as independent variables. Through arithmetical operation including derivation of function and so on, the effect of precipitation on tree growth was studied through the rejection of effect of time factor. [ABSTRACT FROM AUTHOR]

Using a non-heated solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC–MS) method, the impact aroma compound, 2-acetyl-1-pyrroline (2AP), was confirmed to naturally occur in the water of the aromatic Thai coconut cv. Nam-Hom and not in the other cultivars studied. The fruit was also harvested at different stages of maturity and at monthly intervals over a year, and the water was analyzed. 2AP was first produced 5.5 months after fruit set and continued to accumulate until physiological maturity at 11 months. The content varied with the season, being high in the dry period and low in the rainy period. This variation in 2AP concentration during the course of the year was in good agreement with changes in the aroma and sweetness of the coconut water. [ABSTRACT FROM AUTHOR]

In typically anemophilous families, there are species, such as Rhynchospora ciliata (Cyperaceae), in which both wind and insects have been registered as pollen vectors (ambophily). However, the contribution of each vector to pollination of ambophilous species can change under different environmental conditions. Therefore, this study aimed to determine the primary pollination system, abiotic or biotic, of R. ciliata, comparing wet and dry seasons. We tested the following hypotheses: (1) in dry months, wind is the main pollen vector of R. ciliata; (2) in wet months, insects will contribute more to the reproductive success of R. ciliata and compensate for low fruit formation by the abiotic vector. Our hypothesis was not confirmed. We found that higher wind speed can favor pollination by wind in R. ciliata even in wetter months. Because insects were less susceptible to environmental variation, they contributed more in dry months when wind speed was low, thus compensating for lower fruit set by wind. High rainfall and humidity can result in faster settling of pollen grains suspended in the air; however, rainfall does not prevent pollination by wind. Since individuals of R. ciliata are located near the edge of the forest, grouped quite close together, and as the inflorescence is located at the apex of the floral scape, wind can act as pollen vector and the inhibiting effects of rainfall can be minimized. The contribution of each pollen vector is important to the reproductive success of R. ciliata and the effectiveness of wind varies with local environmental conditions. [ABSTRACT FROM AUTHOR]

The effects of climate change including warming on nitrogen (N) availability and growth ofPinus merkusiiin central Vietnam were investigated using the relationship between climate variables (rainfall and temperature) and tree-ring parameters (ring width, density, basal area increment, and N concentration) for the last five decades. Rainfall was not correlated with any tree-ring parameters, indicating that water availability did not limit tree growth in the study site probably due to sufficient rainfall. Temperature was positively correlated with ring N concentration, basal area increment, and ring density, probably reflecting the positive effects of warming on soil N mineralization, net photosynthesis, and cell wall thickness, respectively. Therefore, this study suggested that global warming during the last five decades increased N availability and the increased N further helped warming-induced increases in the growth ofP. merkusiiin central Vietnam. [ABSTRACT FROM PUBLISHER]